MXPA96002231A - Injection molding machine with associated fixing / clamping assembly and a related control system and method - Google Patents

Abstract

The present invention relates to fixing / clamping system for use with platinas of a molding machine, comprising: tie bars for guiding plates, means for movement to position one of the plates with respect to another of the plates; fixing / clamping to forcefully connect one of the plates with the other of the plates and one of the connecting rods for the forced forced coupling of one of the plates with the other of the plates and the connecting rods, and to separate the of the plates and the connecting rods, the fixing / securing means comprises means of the body member including means for securing one of the plates to at least one of the connecting rods; the securing means rotates to coupling and uncoupling with the at least one connecting rod, the plates have perforations for receiving the body member means, characterized in that the body member means have a structure that moves e as a single unit and have an outer surface that is configured to form two cavities between the outer surface and the perforations to receive a pressurized fluid, a cavity is for the forced forced coupling of one of the plates with another of the plates and the other cavity is to separate the one of the platinas from the other of the platin

Description

INJECTION MOLDING MACHINE WITH ASSOCIATED FIXING / CLAMPING ASSEMBLY AND RELATED CONTROL SYSTEM AND METHOD BACKGROUND OF THE INVENTION This invention is directed to injection molding machines that use tie rod fastening units, and more particularly, to a control system for controlling the clamping and breaking of the mold of the tie bar clamping units. The prior art includes many injection molding machines that use tie bar clamping units to place a platen for the application of clamping forces. Control systems using a hydraulic fluid, pressurized air and electric motors in combination with various switches and typically a controller unit are used to control the placement of both of the plates and the application and removal of the clamping force to acquire a clamp of the mold and the breaking of the mold. Japanese Patent 61261-017 describes a clamping mechanism for injection molding machines. The purpose of the control system here is to maintain a parallel separation line between the molds detecting the distance traveled by each clamping cylinder in each tie bar and keeping the distance substantially equal. Accordingly, the parallelism of the separation line between the molds can be maintained when the injection pressure of the melting resin is not uniform inside the mold. U.S. Patent 4,832,884 to Speck et al. Discloses a method for measuring and controlling the closing force of a plastics injection molding machine. Accordingly, for an injection molding machine, a closing force is measured for a predetermined number of operating cycles. An average value is calculated from the measurements and if the average value is within a predetermined tolerance, no control intervention takes place. However, if the average value falls outside the tolerance but within a zone limited by alarm units, a control intervention is presented by gradually changing the installed height of the mold until the actual value measured for the closing force after each Operation cycle falls within the given tolerance. In this method and system, a knee joint system serves to generate the closing force on the first and second mold parts. In this case, the force is measured and if the force falls within a tolerance zone, the space between the first and the Second parts of the mold are altered to a lesser extent or without any relative increase in the previous force. U.S. Patent 4,966,738 to Inaba et al. Discloses a method for adjusting the clamping force of the mold. Accordingly, in this method, a contact position of the mold is detected, in which the halves of a mold come into contact with each other. The temperature of the mold is detected by means of thermoelectric pairs provided in the mold halves. The thickness of the mold is obtained based on the position where a moving platen and a stationary platen of the injection molding machine come in contact with each other. After the molding operation is initiated, the temperature of the mold is detected and the amount of change in the thickness of the mold during a period between a "preceding cycle and an ongoing cycle is calculated based on the change in mold temperature, the Mold thickness and mold thermal expansion coefficient A mold contact position for an ongoing cycle is obtained based on the calculated value Therefore, when the mold is clamped in the current cycle, the moving stage moves from the contact position of the mold to the stationary platen with a predetermined amount to produce a predetermined clamping force of the mold.For this method, the measurements and adjustments are directed mainly to the position of the mold and no to the position of the clamping units. A clamping unit is a single unit that works to force the moving platen against the stationary platen. That is, internal tie bar clamping units are not used on any deck to produce the clamping force. U.S. Patent 5,147,161 to Kurumaji et al. Discloses a mold alignment device for a compression molding machine. The mold alignment device includes a plurality of cylindrical mold position adjusting actuators arranged on a bed where the position detectors are associated with the cylindrical position adjusting actuators of the mold to detect the blows thereof. The hydraulic source for driving the cylindrical actuators for adjusting the position of the mold and the control unit for controlling the impacts of the piston rods of the actuators with reference to the zero points of the piston rods of the actuators, is determined in advance . The zero points are decided by placing the upper mold in close contact with the lower mold and by extending the piston rods of the actuators so that the piston rods are pressed against the lower surface of a sliding block. The piston rod strokes are controlled during an operation of molding-compression so that the upper mold is held precisely in parallel with the lower mold. This device is aimed at pressure molding. The cylindrical actuators are not placed inside the mobile fusion plate, and the actuators are not clamped on the tie bars. The main purpose of the machine is to maintain a parallelism between the upper and lower molds by means of placing a direct pressure of the actuators on the upper mold support surface in order to maintain it parallel to the lower mold. U.S. Patent 5,338,171 to Hayakawa et al. Discloses a die holding apparatus with an alignment device. The apparatus includes a stationary punch plate for holding a stationary punch, a movable punch plate for holding a movable punch, a hydraulic cylinder for moving the punch plate movable back and forth with respect to the stationary punch plate, and A connecting rod for fastening by means of a clamping device located on the mobile die plate. One or more alignment devices are provided so that the movable die and the stationary die are attached in such a way that the main alignment can be performed. The molding apparatus may be provided with a guide pin for alignment secondary of the movable die with respect to the stationary die when the stationary die and the movable die have been placed in predetermined positions. Four die clamping cylinders have been provided in the corners of the stationary die plate so that a stationary and movable stationary clamping force is applied once the clamping device has been clamped to the tie rod. For this device, the fastener of the tie bar and the clamping units, although located on bars of the tie bars, an I adjacent to the moving platen and one adjacent to the stationary platen, are separate devices that increase the complexity of the machine. U.S. Patent 5,370,518 to Sasaki et al. Discloses an apparatus for injection and compression molding. The apparatus includes an injection device and a compression molding device in which the compression molding device includes a stationary punch plate for holding a stationary punch, a mobile punch plate for holding a mobile punch, means for spreading and rapidly retracting the movable die plate relative to the stationary die plate and means for closing the mobile die plate to the tie bars at a position where the movable die plate approaches the stationary die plate. I also know they provide means for holding the dies once the stationary die plate is attached to the tie bars. An injection device for feeding a molten plastic material into a mold cavity between the stationary die and the movable die initiates the feeding of the molten plastic material into the mold cavity when the stationary die and the movable die are separated from each other with a distance default The plastic material is compressed and applied when the movable die moves towards the stationary die after a predetermined amount of the molten plastic material has been fed into the mold cavity. The apparatus includes a device in a movable die plate for attachment to the tie bars. However, the device does not include combined means for providing the clamping force between the plates and attaching to the tie rods, since the clamping force is provided by separate die clamping cylinders which are placed on the tie rods but separated from the fasteners. There is, based on the deficiencies of the devices that have been discussed in the foregoing, the need for a system that includes a control system and process to control the mechanisms of attachment of the tie bars that works to involve tie bars, provide a mold holding force and a force of rupture of the mold, in which the control system is operative with the fastening mechanisms of the tie bar to establish consistently adjustable starting positions for the fastening mechanisms of the tie bar in which the necessary blow is provided for the clamping and breaking forces of the mold.

BRIEF DESCRIPTION OF THE INVENTION The main object of this invention is to provide a control system for use in the control of the fastening mechanisms of the tie bar in injection molding machines. Another object of this invention is to provide a control system for use with the fastening mechanisms of the tie bar for an injection molding machine, whose link bar mechanisms work to involve the tie bars, provide clamping forces and also to provide mold breaking force. Still another object of this invention is to provide a control system and a process that is operative with the fastening mechanisms of the tie bar to place the same in the proper adjustable starting position after each molding operation so that it is contemplated Consistently enough blow for clamping and breaking the mold. Still another object of this invention is to provide a control and process system that is operative with the fastening mechanisms of the tie bar to adjust the starting positions of the mechanisms to accommodate different mold sizes and respective closing heights. The objects and advantages described herein are achieved through the system and process of the present invention. The system is a fixing / clamping system for use with platinas of a molding machine. The system comprises connecting rods for connecting the plates; a device for placing one of the plates in the connecting rods connecting the plates and in relation to the other of the plates; and a fixing / clamping mechanism to forcefully involve one of the plates with the other and on the clamping bars, to sustain a forced involvement of one of the plates with the other and the tie bars, and to separate one of the plates from the other. the plates of the other and of the tie bars. The process for controlling the activity of the mold of a molding machine having fixing / holding means and one half of the moving mold placed on a moving platen and another half of the mold placed on another platen, comprises the steps of supplying fixing / holding means and means for holding the fixing / holding means, the fixing / holding means for placing such a moving mold platen on the means for holding and in relation to the other platen, for forcibly involving such a moving mold platen with the other platen and on such means for holding, for holding the forced involvement of such a moving mold platen with the other platen and the means holding and separating the moving platen from the other platen and holding means. ; determining an adjustable starting position of the fixing / holding means and of the movable mold half, characterized in that in the adjustable starting position a sufficient blow is provided to the half of the movable mold for the fastening of the mold and the breaking; checking after each clamping if the adjustable starting position is sufficient for the proper mold clamping; adjusting the adjustable starting position if necessary after each revision stage to achieve greater accuracy; actuating the fixing / holding means to develop a clamping force; providing means for developing the clamping force in such clamping / holding means for such a driving step; monitoring and control of the position of the fixing / securing means; and the maintenance of the clamping force at the prescribed level.

The details of the present invention are set forth in the following description and drawings in which the reference, the characters illustrate similar elements.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a simplified top view of a tandem injection molding machine having fastening / holding assemblies in accordance with the principles of the present invention; FIGURE 2 is an elevation view of the tandem injection molding machine as shown in FIG.

FIGURE 1; FIGURE 3A is a detailed cross-sectional view of a fastening / fastening assembly for use with the injection molding machine in accordance with the principles of the present invention, showing the teeth engaged in the upper half and the teeth uncoupled in the lower half, taken along line 3A-3A of FIGURES 6A and 6B; FIGURE 3B is a terminal cross-sectional view, partially of a fastening / -sussembly assembly used with an injection molding machine in accordance with the principles of the present invention, taken along line 3B-3B of the FIGURE 3A; FIGURE 4 is a terminal view of the injection molding machine shown in FIGURE 1 in accordance with the principles of the present invention and showing the fastening / fastening assemblies and the rotational mechanisms thereof; FIGURE 5 is an elevation view of a single mold injection molding machine in accordance with the principles of the present invention; FIGURE 6A is an elongated view of the rotational mechanism shown in FIGURE 4 in the decoupled position; FIGURE 6B is an elongated view of the rotational mechanism shown in FIGURE 4 in the engaged position; FIGURE 7 is a schematic diagram of a control circuit system that is operational to control the mold-breaking activities of the injection molding machine of FIGS. 1-6B, as well as to readjust the positions of the assemblies fixing / fastening according to the principles of the present invention; FIGURE 8A is a schematic, partial view of the movable platen, the fastening / holding assembly and the stationary platen identifying the positions of those elements used in the calculations by a controller, and in accordance with the principles of the present invention; Y FIGURE 8B is a schematic, partial view of the movable platen, fixation / clamping assembly and the stationary platen that identifies the position variables used in the calculation of an adjustable starting position in accordance with the principles of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY Referring now to the drawings in detail, in FIGURE 1, a simplified top view of a tandem injection molding machine according to the principles of the present invention and generally designated as 10 is shown. The machine 10 generally includes a fixed central stage 12, a mobile terminal stage 14, a mobile terminal stage 16, an injection unit 18, junction bars 20a-21 (20c and 20d are shown in FIGURES 4), 21a-21d (21c and 21d no shown) and 23a-23d (23c and 23d not shown) for guiding the movable plates and fastening / clamping assemblies 22a-22d (22c and 22d shown in FIGURE 4). The central platen 12 is fastened to a base and the mobile terminal platens 14 and 16 move away from and approach the central platen 12 by means of positioning cylinders 25 and 27, respectively, as shown in FIG.

FIGURE 2. The central platen 12 includes a molding end 24 having a stationary first mold half 26 and a molding end 28 including a second stationary mold half 30. In addition, the central stationary platen 12 includes a first hot channel 32 for directing the melt to the first stationary mold half 26 and a second hot channel 34 for directing the melt to the second stationary mold half 30. The closing projections 36a and 36b extend from the end of the fixed center stage to alternate the coupling with the injection unit 18. Alternatively, a single fixed connection can be used with a distribution valve to feed the resin to either side in the central platen and to the respective mold. The movable platens 14 and 16 each include a movable mold half 29 and 31, respectively, to form the molds upon closing with the stationary mold halves 26 and 30, respectively. With reference to FIGURE 1 and FIGURE 2 showing an elevation view of the machine 10 shown in FIGURE 1, the tie bars 20a-20d (20c not shown) extend from the fixed center stage 12 towards the terminal stage 14 movable and four connecting rods 21a-21d (21d not shown) extend from the fixed central stage 12 to the mobile terminal stage 16. The connecting rods 20a-20d and 21a-21d are arranged in the equines of the central stage 12 fixed so that when the mold is closed, these extend through the fastening / holding assemblies 22a-22d (22c not shown) and 23a-23d (23d not shown), respectively, transported or within the terminal platens mobile 14 and 16, respectively. The tie bars are preferably stationary while the movable platens move relative thereto and are supported on guide shoes, the shoe 23a is shown in FIGURE 3A. Each of the terminal platens 14 and 16 includes four perforations shown in the dashed lines in FIGS. 1 and 2, 35a-35d (35c not shown) and 37a-37d (37d not shown), respectively, in which extend clamping and clamping assemblies 22a-22d and 23a-23d, respectively. The movable platens 14 and 16 preferably include fasteners, shown in FIGURE 4, on the outer front surface thereof for fastening the fastening / fastening assemblies, respectively. Fixing / clamping assemblies work both to hold or attach the tie bars and apply pressure to the mold halves during injection of the mold. Accordingly, from a general point of view, each of the fastening / clamping assemblies 22a-22d and 23a-23d includes a mechanism for securely engaging and a positive tie bar, wherein the mechanism is further capable of providing a pressure to the platens to force the mold halves to join during injection molding. Preferably, each fastening / holding assembly is formed by a body having a structure that is movable as a simple unit to be secured with the tie rods and to apply a clamping pressure between the platens. All fastening / fastening assemblies, perforations and tie bars are substantially the same and consequently, only one of the fastening / clamping assemblies 22a, the perforation 35a and the tie rod 20a are described in detail together with their associated elements , unless specifically contemplated, it being understood that the description applies to both the fastening / fastening assemblies 22b-22d, the perforations 35b-35d and the tie bars 20b-20d and the associated elements. In a particular embodiment of the fastening / fastening assemblies, the fastening / clamping assembly 22a is mounted on the outer front end of the mobile terminal pad 14 and within the bore 35a as shown in FIGURES 1 and 4, and as it was discussed in the above. Referring to FIGS. 3A and 3B, for the fixing / holding assembly 22a of the plate 14 to function with the tie bar 20a, the tie rod 20a includes an elongated end section having a plurality of protrusions spaced in the shape of teeth 38a separated by longitudinal slots 40a extending longitudinally as shown in FIGURE 4 and in greater detail in FIGURE 6A for bar 20d. Accordingly, at the end of the tie rod 20a is a toothed outer surface, as shown in FIGURE 3A. The toothed outer surface of the connecting rod 20a is in the form of longitudinal outer strips of teeth 39a that extend in the axial direction of the connecting rod, in which the teeth 38a are preferably aligned in a radial direction on the rod. union and separated by a space in the axial direction. Each of the tooth strips as the teeth strips 39a is radially separated from another tooth strip by means of an axially extending outer groove, such as the outer grooves 40a as shown in FIG. 4. The strips of outer teeth 39a and grooves 40a of tie bar 20a are adapted to engage and align, respectively, with the internal teeth and grooves of fastening / clamping assembly 22a, discussed above, to cause a close engagement with the rod 20 a.

The fastening / holding assembly 22a is positioned in the bore 35a and is secured there by means of a retaining ring 41a and fasteners 42a, as shown in FIGURE 3A. The fastening / holding assembly 22a is formed by a member in the form of a piston 44a adapted to be placed in the bore 35a and coaxially relative to the tie rod 20a, as shown in FIGS. 3A and 3B. The piston 44a includes an outer surface 46a and an inner surface with axially extending teeth 48a separated by spaces in the axial direction, which are adapted to engage the teeth 38a of the tooth strips 39a of the tie rods 20a. A slight axial space is provided between the teeth 38a of the tie rods 20a and the internal teeth 48a of the toothed piston 44a to allow relative movement and an adjustment of positional error during the engagement of the teeth. In FIGURE 3A, the upper half of the figure shows the closing coupling of the teeth 38a of the connecting rod 20a with the inner teeth 48a of the piston 44a and the space, represented by dotted lines in FIGURE 4, although half bottom does not show a coupling. The inner teeth 48a are included in a plurality of axially spaced, radially spaced interior teeth strips, such as in 49a, which are spaced apart radially from one another by the inner grooves 51a, as shown in FIGURE 6A and axially spaced apart. To achieve a relative movement between the clamp / clamp assembly 22a and the tie rod 20a, the outer tooth strips 39a of the tie rod 20a have a radial width smaller than the inner grooves 51a of the piston 44a and the outer grooves 40a of the connecting rod 20a are greater in radial width than the inner tooth strips 49a of the piston 44a, thus allowing sufficient space for axial movement therebetween. During the engagement or disengagement of the tooth strips 39a with the tooth strips 49a, the teeth 38a do not extend over the full depth of the spaces between the inner teeth 48a or "slots 51a, respectively, thus leaving a space between the teeth and the perforation of the piston, so there is a space preferably between the teeth 48a and the innermost surfaces of the connecting rod 20a, ie the surfaces defined by the spaces between the teeth 38a or the surfaces of the grooves 40a. The outer surface 46a of the piston 44a has a stepped shape that preferably includes a base portion 50a having a wider diameter than the neck portion 52a.The bore 35a is formed to receive tightly to the piston 44a at the base and at the neck portion. Accordingly, the perforation 35a has a smaller perforation portion 54a having a diameter only slightly larger than the diameter of the neck portion 52a and a larger perforation portion 56a having a diameter only slightly larger than the diameter of the base portion 50a of piston 44a. The smaller perforation portion 54a and the larger perforation portion 56a are circular in shape and are separated by an intermediate perforation portion 58a having a hemispherical, tapered, stepped or otherwise shaped shape, whose shape selection is not critical. The intermediate piercing portion 58a starts at the smaller piercing portion 54a, expanding outward to its maximum diameter just before the larger piercing portion 56a. The maximum diameter of the intermediate piercing portion 58a is smaller than the outer diameter of the larger piercing portion 56a and the base portion 50a of the piston 44a. Accordingly, a face 60a is formed between the intermediate piercing portion 58a and the larger piercing portion 56a against which the axially transverse surface 62a of the piston 44a can be spliced. With reference still to FIGS. 3A and 3B, seals 64a have been provided between the smaller perforation portion 54a and the neck portion 52a and seal 69a It has been supplied between the larger drilling portion 56a and the base portion 50a of the piston 44a. The intermediate piercing portion 58a is therefore larger in diameter than the transition area 59a between the base portion 50a and the neck portion 52a, defined in part by the axially transverse surface 62a of the piston 44a. Accordingly, the clearance 66a is supplied between the perforation 35a and the piston 44a in the vicinity of the intermediate piercing portion 58a. This space 66a is appropriately sealed by means of the seals 64a and 69a, for the introduction of pressurized air, hydraulic or other fluid to supply a clamping pressure against the surface 62a of the piston 44a to press the moving platen 14 against the fixed center stage 12 during injection molding. Additional seals 63a are preferably provided between the retaining ring 41a and the piston 44a. The clamping pressure is released by releasing the hydraulic pressure from the space 66a and applying the hydraulic fluid under pressure in the cavity 65a against the surface 67a of the piston 44a. Before applying the pressure in the space 66a against the surface 62a to force the mobile stage 14 against the fixed center stage 12, the inner teeth strips 49a of the piston 44a must first be engaged with the outer teeth strips 39a the connecting rod 20a. Such closure coupling, and uncoupling, the inner strips 49a with the outer strips of teeth 39a is achieved by means of the rotational mechanism 68, shown in FIGURE 4. The rotational mechanism 68 is used to rotate the clamping / clamping assemblies 22a-22d and is substantially the same rotational mechanism (not shown) used with fastening / clamping assemblies 23a-23d. Accordingly, only the rotational mechanism 68 will be described in detail, it being understood that the description applies equally to the rotational mechanism used with the fastening / clamping assemblies 23a-23d. As shown in the terminal view of FIGURE 4 where the fastening / clamping assemblies 22a-22d are shown positioned on the moving platen 14, the rotational mechanism 68 is preferably in the form of a joint assembly extending between and it is connected to all four fastening / holding assemblies 22a-22d on the mobile terminal plate 14. The rotational mechanism 68 specifically connects the clamping / clamping assemblies 22a and 22b and the clamping / clamping assemblies 22c and 22d. The articulation assembly of the rotational mechanism 68 includes one or more, preferably a pair, of piston / cylinder mechanisms 70 and 71 attached to the support 72 between two fastening / holding assemblies, i.e. the fastening assemblies 22a and 22c.

Both the piston / cylinder mechanisms 70 and 71 and the associated linkage are substantially the same and accordingly only a piston / cylinder assembly 70 and associated joint will be described in detail, it being understood that the description equally applies to the piston assembly 71. / cylinder, wherein the assembly 71 is substantially the symmetrical image of the assembly 70. The non-moving end of the piston / cylinder assembly 70 is pivotally attached to the support 72 and the end 73 of the rod of the piston assembly 70 / cylinder extending towards the fastening / clamping assemblies 22a-22b. The piston rod 73 extends from the assembly 70 of the piston / cylinder and is attached by means of a bearing assembly 76 to the terminal surface 77a of the piston 44a. The link arm 80 is attached to the bearing assembly 76 which pivots about a pin 78 fixed to the terminal surface 77a. The articulation arm 80 traverses a portion of the terminal surface 77a of the piston 44a and is connected to another pin 82 on the terminal surface 77a. The bolts 78 and 82 are preferably spaced apart from one another on the terminal surface 77a of the piston 44a, at approximately 90 °. Bolt 78 is preferably positioned at the outer end 83 of the vertical center line of the fastening / holding assembly 22a. A second articulation arm 84 extends from the bolt 82 which connects the fastening / holding assemblies 22a and 22b and is attached to the terminal surface 77b of the piston 44b. The articulation arm 84 is pivotally attached to the fastening / fastening assembly 22b on a bolt 86, in which the bolt 86 is positioned in the fastening / fastening assembly 22b adjacent to the exterior end 87 of the vertical center line of the fastening assembly. / fastening 22b. The dotted lines in FIGURE 4 indicate the movement of the rotational mechanism 68 by the drive of the piston / cylinder assemblies 70 and 71. The solid lines show the pistons in the non-extended position with the inner teeth strips 49a-49d of the pistons 44a-44d being decoupled with the outer teeth strips 39a-39d from the tie rods 20a-20d. The dotted lines of the fastening / holding assemblies also show the inner teeth strips 49a-49d of the pistons 44a-44d coupled with the outer teeth strips 39a-39d of the tie rods 20a-20d. This coupling and uncoupling is shown in greater detail in FIGS. 6A and 6B, with FIGURE 6A showing the fastening / holding assembly 22d in the uncoupled position, ie, the strips of teeth 39d and 49d disengaged and FIGURE 6B shows the fastening / clamping assembly 22d in position coupled with the meshed 39d and 49d tooth strips. Accordingly, at the time of the simultaneous actuation of the piston / cylinder assemblies 70 and 71, the inner teeth strips 49a-49d, the fastening / clamping assemblies 22a-22d, respectively, can be coupled and disengaged synchronously with the strips outer teeth 39a-39d of the connecting rods 20a-20d, respectively, so as to close the movable plates 14 and 16 in the substantially closed positions prior to the application of the desired clamping force by means of the pressure against the surfaces 62a-62d (shown in FIGURE 3; 62b-62d not shown), of the pistons 44a-44d (44b-44d not shown). The total available displacement of the piston 44a is at least the total pitch of the tooth strips plus the space plus the maximum elongation of the tie rods. This allows the closing height to be adjusted to any point between the maximum and the minimum even though the coupling between the teeth of the connecting rod and the teeth of the piston are of a fixed pitch. Although the rotational mechanism 68 has been described in detail as an articulation assembly, it should be understood that other types of rotational mechanisms may be used such as, for example, toothed crowns, belts and 2 G chains, directly synchronized impellers and rack-and-pinion assemblies. Although the fastening / clamping assemblies 22a-22d of the present invention have been described for use with a tandem injection molding machine having a fixed central platen and two movable endplates, the clamping / clamping assemblies are not No way limited to such use. The assemblies 22a-22d may be incorporated in a manner similar to that described above for tandem-type mechanisms having a fixed terminal stage and movable plates towards the fixed terminal stage. The use of fastening / clamping assemblies is also feasible and is contemplated for other variations of tandem machines. In addition, the fixing / holding assemblies can be used in the same way with machines 210 not in tandem, as shown in FIGURE 5, ie injection molding machine having a single plate 214 of the stationary mold and a moving plate 212 or any other related variation. Accordingly, FIGURE 5 is indicative of the use of fastening / fastening assemblies 22a-22d, assemblies 222 of the present invention with a 210 machine not in tandem. The above description of fastening / fastening assemblies, rotational mechanisms and additional parts of the injection molding machine, they are equally applicable to a non-tandem machine and are incorporated herein. Alternatively, the assemblies 222 can be mounted on stationary plates 214 and tie bars attached to the moving plate 212. Referring now to FIGURE 7, the control system 100 of the present invention is shown schematically. The control system 100 is operative to individually control each of the clamping / clamping assemblies 22a-22d (22c and 22d not shown in FIGURE 7). The control system 100 generally includes a controller 102, a four-way servo valve 104, preferably a highly dynamic servo valve, used for the control of axial movements of all four fastening / holding assemblies, cartridge valves 106a- 106d used to disable or disable the movements of each of the fastening / clamping assemblies 22a-22d (22c and 22d not shown), a plurality of linear position measuring devices 107a-107d (107c and 107d not shown), preferably linear transducers for measuring the position of the fastening / holding assemblies, a pressure transducer for measuring the pressure of the fastening assemblies, a closing valve 108 for facilitating the separation of the hydraulic supply from the fastening assemblies to prevent movements on the holding pistons and keep the clamping force, when it is reached, a closed circuit controller 110 for controlling clamping tonnage, a logic monitoring circuit 112 for use with linear position measuring devices 107a-107d (107c and 107d not shown) ) for measuring the positions of the fastening / clamping assemblies 22a-22d (22c and 22d not shown), and a manifold 114 for controlling the clamping / clamping assembly to rotate the clamping / clamping assemblies towards the coupling with the clamping bars. Union. The controller 102 (shown schematically) is operative with these elements and other elements described below to provide a system and process for intricately controlling the movements of the fastening / clamping assemblies 22a-22d (22c and 22d not shown). The controller 102 (shown schematically) is operative to coordinate the operations of various valves and other elements in the control system 100. The cartridge valves 106a-106d for each of the fastening / clamping assemblies 22a-22d (22c and 22d not shown), function respectively to enable each of the fastening / clamping assemblies 22a-22d to provide a clamping force to halves 30 and 31 of the mold. The cartridge valves 106a-106d provide an enabling condition for the fixing / holding assemblies 22a-22d (22c and 22d) not shown) when it has been verified that the fastening / holding assemblies are in engagement with the connecting rods 20a-20d (20c and 20d not shown), respectively. Sensors (not shown) are used to verify such coupling of the fastening / holding assemblies with the tie bars. The attachment of the fastening / clamping assemblies 22a-22d (22c and 22d not shown in FIGURE 7) with the tie rods is established by means of the clamping / holding assembly control manifold 114 which provides a pressurized fluid for the rotational mechanism 68, by rotating the fastening / clamping assemblies 22a-22d (22c and 22d not shown) by coupling them with the tie rods. Under control of the controller 102, the manifold 114 is activated when the local position is reached as further discussed in the following. Once enabled, the status of the enabled condition is confirmed by limit switches (not shown) installed on the four cartridge valves 106a-106d. An open situation for each of the cartridge valves forms an interlocking condition for clamping. A loss of this situation detected by the controller 102 constitutes a failure condition and the clamping action will be terminated and the fixing / clamping assemblies 22a-22d (22c and 22d not shown) will be ventilated to the tank.

The servo valve 104 is operative to provide a predetermined flow rate of hydraulic fluid or the like for the fastening / clamping assemblies when the controller 102 verifies that the cartridge valves 106a-106d have enabled each of the fastening / clamping assemblies 22a -22d (22c and 22d not shown). The closed circuit controller 110 (shown schematically) is provided to regulate the rate of increase of the hydraulic fluid supplied by the servo valve 104, and consequently, the rate of increase of the clamping force. The closed circuit controller 110 provides control to the system for rapid accumulation of clamp tonnage until the tonnage reaches the required set point. The closed loop controller 110 also prevents the clamping tonnage from exceeding the recommended set point. The controller 102 also includes an additional logic monitoring circuit 112 (shown schematically) which prevents the clamping / clamping assemblies from experiencing an accumulation of unequal clamping forces relative to each other. Such an inequality could cause mechanical damage. Linear position measuring devices 107a-107d (107c and 107d not shown), such as linear transducers, are used in conjunction with the monitoring logic 112 to measure the positions of each of the fastening / clamping assemblies 22a-22d (22c and 22d not shown) at all times and positioned adjacent to the fastening / clamping assemblies 22a-22d, as shown. The controller 102 is provided with a maximum allowable deviation recommended in position and accordingly, measurements of the linear position measurement transducers 107a-107d (107c and 107d not shown) are used to maintain each of the fastening / holding assemblies within the recommended deviation. In case the maximum deviation measured by the transducers exceeds the maximum permissible value, the clamping process will be terminated and the fastening / clamping assemblies will be ventilated to the tank. The recommended level of the clamping tonnage can be regulated continuously "by the servo valve 104 under the closed loop pressure control or it can be maintained by a closing valve 108 to avoid the diversion of the clamping tonnage of the recommended level until it is finished. the molding process The proximity switches 116, shown schematically in FIGURE 7, monitored by the controller 102, are provided with the rotation mechanism 68 to determine the angular orientations of the fastening / holding assemblies 22a-22d, to ensure an appropriate alignment with the connecting rods 20a-20d.

Referring now to FIGS. 1-8, the operation of the injection molding machine 10 according to the principles of the present invention will be described. In operation, with specific reference to the FIGURES 6, 8A and 8B, of the tandem machine 10 shown in FIGURES 1 and 2, the rotational mechanism 68 for at least one of the movable platens 14 and 16, as shown in FIGURE 4, is set at so that the plurality of fastening / holding assemblies 22a-22d and 23a-23d, respectively, are decoupled with the connecting rods 20a-20d and 21a-21d, respectively, that is to say where the grooves of the bars. The fastening / fastening joint and assemblies are in alignment with the teeth of the fastening / clamping assemblies and the connecting rods, respectively, thus allowing the movement of one of the movable platens 14 and 16 in relation to the connecting rods and the central fixed stage 12, as shown in FIGURE 6A. As an example only, the movable platen 14 moves first towards the closed position of the mold, as shown in FIGURE 2, while the mobile platen 16 remains in the open position of the mold, as shown in FIGURE 2. When the closed position of the mold of the mold halves 26 and 29, as shown in FIGURE 2, the movable mold half 29 is moved by means of the cylinder 25 of position engaging with the first half of the stationary mold 26. In addition, the injection unit 18 is closed in engagement with the closing flange 36a of the first hot channel 32, as shown by the dotted lines in FIGURE 1 or alternatively, a distribution valve is used to direct the flow towards the halves 26 and 29 of the mold. Accordingly, during the movement of the mobile terminal plate 14, the rotational mechanism 68 for the mobile stage 14 is in the position as shown by the solid lines in FIGURE 4 and the fixing / holding assemblies 22a-22d are movable in relationship to the tie bars 20a-20d, respectively. When the first half of the stationary mold 26 and the first half of the movable mold 29 are in the position shown in FIGURES 1 and 2, under the control of the control system 100 and specifically of the controller 102, and through the application of the manifold 114 of control of the rotational clamping / securing assembly, the rotational mechanism 68 is actuated by means of the piston / cylinder assembly 70 and 71 so that the inner tooth strips 49a-49d of the pistons 44a-44d are rotated by engaging the external tooth strips 39a-39d of the connecting rods 20a-20d, respectively. The actuation of the rotational mechanism 68 is carried out only when all the fixing / clamping assemblies 22 are placed in their local positions. The proximity switches 116, which are monitored by the controller 102, are provided with the rotation mechanism 68, are used to determine the angular orientations of the fastening / holding assemblies 22a-22d, to ensure proper alignment with the bars 20a-20d, before rotation. Due to the thermal effects, such as expansion, on the platens and the body of the injection molding machine during molding, the optimal starting position or local position of the fastening / clamping assemblies can be changed and consequently is redeterminate after each molding cycle, as described below. The local position a of adjustable start can be defined with reference to FIGURES 8A and 8B. Each piston 44 has a zero position designated C which defines the position of the pistons fully retracted in the clamping direction. Each piston also has a fully extended, unclamped position defined as the maximum position cma? ' The value of which also defines the mechanical displacement of the piston 44. When one of the moving plates 14 and 16 is positioned by the cylinders 25 and 27 (illustrated in FIGURE 7), respectively, the movable plates preferably have a spacing of the stage stationary equal to the maximum closing height for the mold that is being used, plus a compensation, which may preferably be 30 mm. In this position, when the piston is fully extended to its maximum position Cma, the ends of the tie bar 20 are preferably aligned with the outer surface of the base portion 50 of the piston 44. When calculating the local or starting position of piston 44, other variables are used apart from CQ and Cma ?, As illustrated in FIGURE 8B, Cca? defines the local position of the displacement piston 44 at the maximum closing height. By virtue of the mechanical design, Cca ± can be defined as Cma? - compensation, preferably 30 mm, so that this position when the moving stage is at the maximum closing height, the piston has a sufficient displacement to provide the fastening and a maximum mold break, as well as spaces in the fixing assembly / sufficient support. The space G of the fixing / holding assembly is defined as the space between the inner teeth 48 and the teeth 38 of the piston 44 and the connecting rod 20, respectively, is also used to determine the local position of the clamping piston at different closing heights. P defines the pitch of the teeth of the piston 44 and of the connecting rod 20, m ^ n defines a minimum clamping displacement based on the stretching of the clamping bars with the recommended tonnage, cCUshion (damping) defines a damping distance provided so that the piston 44 does not reach the bottom against the walls of the perforation 35 when clamping is performed. The following table presents the mechanical dimensions of the parameters described above for particularly small or large clamping units.

The controller 102 uses the variables discussed above in the calculation of the starting or local position Chome (local) of each fixing / holding mechanism by means of a product of a computer program that presents a readable computer code. The controller 102 preferably uses the following formulas supplied in the code to calculate the local or adjustable starting position, which position allows sufficient and optimum displacement for clamping and breaking the mold. The formulas are the following.

Algorithm 1 c? s [^ - (Sh, », - Sh.a] nod P SI Cioeai < a, then c ^ = c ^ d + P, where a - C ^. + C ^ + G, and where (X) mod P is operative to return the rest after X is divided by P.

For the previous calculations used by controller 102, the actual closing height Sh -j. it is measured directly from the machine when the molding halves 26 and 29 are closed. In accordance with the above formulas used by the controller 102, the fastening / holding assemblies are placed in their optimal local positions on the tie bars so as to achieve the mold breakage displacement and clamping displacement required. In addition, the above formulas can be used together with the following formulas to achieve that a minimum volume is maintained in the chambers of the fastening / clamping assemblies 22a-22d so that the clamping time and rigidity of the clamping / clamping mechanisms be minimized when the maximum mold breakage displacement is not required. The formulas are the following: Algorithm 2 S¡ «-C ^ -G > Mbr ^ - »- P, .ntonc. C. - C + P To recover from situations where the clamping / clamping assemblies 22a-22d are not completely rotated, without possible damage to the mechanical assemblies due to movements without complete spaces, the following algorithms are used to provide design parameters that minimize possible damage to the mechanical assemblies that have been revealed here. When considering the mechanical design of the system, the space of the complete fastening / clamping assembly is always fulfilled if the following relationship is satisfied where: cobietivo = Fixing / clamping assembly separation position. Shrea "= Actual mold position (Actual closing height) cact = Actual position of the clamping cylinder Shma? = Position of the displacement at the maximum mold closing height n = Full number (0, 1 ... ) (Sh ^ - C. - (Sh, - C ^ - n x P The problem is reduced to finding a c0h-iet vo -ie it is at the shortest distance from the Cact. Therefore, the algorithm is as follows: Algorithm 3: X - Usi - S,) - (c * - C.J] Mod P If X> (P-X), then X = (X-P) c - * - jeow s C ^ - X From the previous algorithm it is applied to calculate the space of the fixation / clamping assembly, while the algorithms 1 and 2 are applied for the calculation of the position local. To avoid using the local position calculation algorithms for the space of the fixation / clamping assembly, it is because algorithm 3 does not take into account the displacement of the mold rupture. In the case of loss of the condition of "fastening / fastening assembly coupled" and condition "fastening / fastening assembly decoupled", the position of the actual fastening piston Cact is compared to the target, target for the fastening / fastening assembly space. If the absolute difference is less than or equal to G then the controller will move the clamping pistons to the target position of the clamping / clamping assembly space before turning the clamping / clamping assembly to the decoupled position. Nevertheless, if the absolute difference is. calculated greater than G, the clamping / clamping assemblies will be rotated without any movement of the clamping piston. This last situation involves the possible contact of the teeth of the fixing / clamping assembly and of the connecting rods. This control scheme will be applied when starting with open mold or closed mold during manual operation. The strategy is adopted to get out of the closing position and minimize mechanical damage to the machine. To provide a more efficient operation during the automatic cycle, the assembly space of Fixation / clamping is obtained again after the mold is broken by the displacement of the mold displacement cylinder by a smaller distance G in the opening direction. Since the clamping pistons are in contact with the tie bars at the end of the mold breaking operation, the opening of the moving platen by a shift of G will provide the space for the necessary clamping / clamping assembly. The repositioning of the holding pistons to the local position will be carried out after the fixing / holding assemblies are turned to the uncoupled position. The initial position of the molding halves is achieved by moving the moving platen gradually until the tooth strips 39a-39d and 49a-49d are respectively in position for coupling. The rotational mechanism 68 under the direction of the manifold 114 rotates the fastening / clamping assemblies 22a-22d in engagement with the tie rods 20. The coupled position of the fastening / clamping assemblies 22a-22d are represented by the dotted line which is illustrated in FIGURE 4. Such engagement of the outer tooth strips 39a-39d of the tie bars 20a-20d with the inner tooth strips 49a-49d of the pistons 44a-44d is also shown in the upper half of the FIGURE 3A for assembly 22a and in FIGURE 6B for assembly 22d. With the inner tooth strips 49a-49d coupled with the outer tooth strips 39a-39d, respectively, and the first stationary mold half 26 being placed in molding engagement with the first mobile molding half 29 (as illustrated in FIG. 1), • pressure can be applied to the molding halves by means of the fixing / holding mechanisms 22a-22d through the servo valve 104. Consequently, each of the cartridge valves 106a-106d are actuated to enable a clamping movement by means of the pistons 44a-44d of the clamping / clamping assemblies 22a-22d. Once this enablement is detected by the controller 102 through the limit switches (not shown) installed on the cartridge valves 106a-106d, the servo valve 104 is operative to supply a pressurized fluid to the fastening assemblies / fastening 22a-22d. If, however, the enabling condition of the cartridges is detected by the controller 102 as enabled, a failure condition is terminated, clamping action by the enabled clamping / clamping assembly 22a and the assembly 22a is ventilated to the tank. Disabling occurs when the fixing / holding assembly reaches the local position or when the The linear position of the disassemblies 22a-22d deviate too much from an average value, as discussed in detail in the following. If no failure condition is detected, and again referring to FIGS. 1 and 3A, the hydraulic pressure or the like is supplied by means of the servo valve 104 at the readjusted flow rate against the longitudinal transverse surface 62a-62d. (62b-62d not shown) of each of the fastening / clamping assemblies 22a-22d. The hydraulic pressure against the surface 62a-62d causes the first half 26 of the stationary mold and the first half 29 of the movable mold to be joined sealing to each other preparing for injection molding and displacing the piston 44 through the calculated displacement between the local position or start C? oca? and the required clamping position, as shown in FIGURES 8A and 8B. In addition, any spaces between the respective teeth of the clamping pistons 44 and the connecting rods 20 are contemplated during displacement. Through the servo valve 104 under the control of the controller 110, the clamping force is increased between the mold halves. That is, the rate of increase of the clamping force is regulated by the servo valve 104 under the supervision of the closed circuit controller 110. The accumulation of pressure is maintained, therefore, at a predetermined level through of the closed loop controller 110. As a force between the mold halves is maintained by means of each of the fastening / clamping assemblies 22a-22d, and at the appropriate level by means of the closed-loop controller 110, the cast is injected by means of a unit 18 of injection through the hot channel 23 to perform the molding. During any simultaneous movement of the four clamping pistons, it is essential to make the clamping pistons move synchronously. For this reason, the synchronous operation is monitored by a function, called synchronization monitor 112 shown in FIGURE 7. The function is started when it is measured that the clamping pressure exceeds a minimum threshold value during simultaneous movements of all four pistons. At the start of the monitoring logic, the actual positions of all the pistons are read as initial positions. In each sampling time the function, the change in position with respect to the initial position of each piston is calculated and the average value of the change is compared with the change in piston position. During clamping, the positions of all four pistons 44 are measured at all times through the linear transducers 107a-107d in conjunction with the monitoring logic 112, shown in FIGURE 7. Under the guidance of the controller 102, it is allowed only that you are positions deviate from an average value of preference set to 0.5 mm. In case any deviation of any piston exceeds this minimum allowable average value, the controller 102 aborts the clamping movement and all the clamping / securing assemblies 22 are vented to the tank. With reference to FIGURE 7, during clamping, once the clamping tonnage is reached, the closing valve 108 maintains the desired clamping force at the required tonnage until the injection molding is completed and the cooling time has expired . After cooling, the shut-off valve 108 is de-energized by means of the controller 102 and all of the cartridge valves 106 are opened to allow the clamping pressure to vent to a low level for clamping. Therefore, the pressure is reduced in the cavities 66 for the separation of the molds. For a soft decompression and separation without any hydraulic shock, the decompression is preferably done following a S-curve time ramp. Similar to clamping, during decompression, the positions of the pistons 44a-44d can be synchronized through of the monitoring by the linear transducers 107 and logic 112, as controlled by the controller 102. After decompression, the fixing / holding assemblies 22a-22d are used to break the mold.

The pistons 44a-44d are held in engagement with the tie rods 20a-20d and the fastening / clamping assemblies are driven in the backward direction by the pressurized fluid through the servo valve 104 and against the surface 67a- 67d (67b-67d not shown) of the pistons 44a-44d, as shown in FIGURE 3A. Preferably, the axial space G between the teeth of the piston 44 and the connecting rod 20 engaged is like the free space for initially separating the halves of the mold. Accordingly, the flow of control through the servo valve 104 for separation is substantially similar to the control flow by means of the servo valve 104 during clamping, except that the fluid is directed in opposite directions. During the whole operation of separation of the molds, the mondoing logic 112 is used to ensure a synchronized movement between all the fixing / holding assemblies 22a-22d. Once the mold separation is completed, the teeth of the piston 44a-44d are rotated out of engagement with the teeth of the tie rods 20a-20d by means of the rotational mechanism 68 controlled by the control manifold 114 of the fastener assembly. /subjection. Once this uncoupling of the teeth has been achieved, the positioning cylinder 25 is operated to move the first half 29 of the moving mold away from the first mold half 26 stationary so that the molded unit can be ejected by the ejection system 88, which is shown schematically in FIGURE 1, the design of which is known in the art. In preparation for the subsequent clamping sequence, it is required that the pistons 44 be repositioned in the local or starting position. The repositioning can take place as long as the pistons 44a-44d are uncoupled from the connecting rods 20a-20d. The repositioning can start even if the opening of the mold has not been completed. Semi-simultaneous repositioning or sequential repositioning can be used for repositioning pistons 44a-44d. For semi-simultaneous repositioning, and referring to FIGS. 3A, 7, 8A and 8B, the process can be divided into two parts that include general control and fine control. To initiate the general control, the cartridge valves 106a-106d enable all the pistons 44a-44d to move in the direction of their adjustable local or starting positions by means of the servo valve 104 directing the pressurized fluid to the pistons. An external window value or threshold value is defined which is in close proximity to the target but which is defined by a distance large enough to avoid an overshoot of the holding pistons. When each clamping piston 44a-44d reaches its external window value or threshold value, a decision logic is used to determine whether to transit to fine control or whether to stop in the outer window. The decision is based on whether any other clamping piston 44 is enabled. If all other pistons are disabled, a piston will transition to fine control when the outer window is reached. Otherwise, if at least one of the pistons is enabled, this is disabled when the outer window is reached. In this way, the continuity of movement of at least one of the holding pistons 44a-44d is conserved. If the clamping pistons are at different ends of the target position when the semi-simultaneous repositioning is started, only the one-way clamping pistons will move towards the target position. When all the pistons on the same side are repositioned then the remaining pistons on the other side will initiate repositioning. According to the above calculations, the controller 102 has calculated the local or adjustable starting position and the linear transducers 107 together with the monitoring logic 112 continuously calculate a distance that each piston 44a-44d has to travel to reach the local position or of adjustable start, as determined from the calculations discussed in the above. As discussed in the foregoing, the controller 102 is provided with an outer window value or threshold value that defines a set distance that the pistons 44 have to travel to the local or starting position. When one of the pistons 44a-44d has reached a position in which the distance to the local or starting position is less than the threshold position value, and all other pistons are disabled, the controller 102 changes to the controller 110 of closed circuit to fine control.- During fine control, the closed-loop controller 110 functions to reduce the flow adjustment of the servo valve 104 preferably to a quarter of the overall control setting to ensure a smooth continuous movement of the clamping piston principal. When the main clamping piston has reached its local or adjustable starting position it is disabled by means of the cartridge valve 106, thus preventing any further movement of that first piston. After the first of the pistons 44a-44d, another piston of the remaining ones is enabled and must be repositioned and selected for fine control. Several selection criteria can be used. For example, the selection can be based on which of the pistons is closest to the local or adjustable start position. Once selected, the other piston is enabled through the cartridge valve 106 and placed in its local or starting position by means of the pressurized fluid through the servo valve 104, controlled in fine form by controller 110. This process continues for all pistons 44a-44d until all pistons 44a-44d are set in their local or starting position. For a sequential repositioning, a strategy similar to the semi-simultaneous approach described in the foregoing can be used, except that the fixing / holding assemblies 22 are repositioned sequentially one after the other. That is, each assembly is controlled as described above but sequentially so that general control and fine control are performed completely for each assembly, one after the other. For the tandem machine 10 as shown in FIGURE 1, since the fastening / clamping assemblies 22a-22d are released and the moving mold half 29 moves to the open position, the other half 31 of the moving mold is closed by means of the cylinder 27 and is held by means of the fastening / clamping assemblies 23a-23d, by means of the same operation as discussed above for the mold halves 26 and 29 and the fastening / clamping assemblies 22a-22d under the control of the controllers 102 and 110. The injection unit 18 moves towards the closing coupling with the closing fasteners 36 of a second hot channel 34, or the direction of the valve is changed to inject the casting and forming a unit molded into the halves 30 and 31 of the mold. The fastening / clamping assemblies 23a-23d (23c and 23d not shown) are designed and operate in the same manner as described above and are repositioned in the same manner as described above. The mold halves 26, 29 and 30, 31 can be opened, closed, clamped and separated dependently from each other. Each end of the stationary stage 12 can be operated as a completely independent machine or can be coordinated and synchronized in one of many ways. FIGURE 5 shows a single mold injection molding machine in which numbers similar to those used for the machine 10 describe similar elements and are not described in detail herein, where reference is made to the preceding description. The machine 210 includes a stationary platen 214 and a mobile platen 212. The injection molding machine 210 includes fastening / clamping assemblies 222, similar to those described above for the tandem machine, on a moving platen 212 and is designed and operated in the manner described above in relation to the assemblies of fastening / fastening 22, tie bars 20 and rotation mechanism 68, except that only a set of fastening / fastening assemblies, tie rods and a rotation mechanism are used.

An additional feature of the present invention that is presented in relation to the protection sensitivity of the mold. Mold protection sensitivity is defined as the ability of the machine to detect trapped parts between the two mold halves. This is calculated as the difference between the closing height measured in the loss of the low tonnage level during decompression after the previous machine cycle is clamped and the closing height measured in the condition of "fastening / fastening assembly coupled" "of the current cycle, where the condition" fastening / fastening assembly coupled "involves the coupling of the fastening / clamping assemblies 22a-22d with the tie bars 20a-20d. The fastening / clamping assemblies are allowed to go towards the "coupled" condition, when the clamping pistons are within a window of a distance less than the target position and the closing height is within a window of a distance smaller than the closed position of the mold. In the case that the closed position of the mold (a smaller window to the height position closed in the last decompression) can not be reached within a period of time, which is measured after the displacement has reached a fixed distance from the mold position closed, the fastening / clamping assemblies will rotate towards an uncoupled position and the mold will open automatically with a "Part Interference" alarm. When the clamping / clamping assemblies move in a "coupled" condition, the clamping of the mold is still active. Since the movement of the fastening / fastening assemblies requires a time to conclude at the end of the "fastening / fastening assembly" condition, the displacement must have reached the minimum closing position driven by the displacement force. This position of the closing height will be used to calculate the local target of the clamping pistons in the next cycle, only if the recommended setting value of the mold protection sensitivity is satisfied. After concluding the condition of "fastening / fastening assemblies coupled", the position of the actual closing height is compared with the position measured during decompression of the previous cycle. The message "loss of mold protection sensitivity" will be presented if the recommended sensitivity value is not achieved after turning the fixing / clamping assembly 22. Consistent occurrences of the "Part Interference" and "Loss of Mold Protection Sensitivity" alarms require the operator's attention to inspect the cleanliness or parallelism of the mold and may require a new closing height calibration. For manual fashion, It is the responsibility of the operator to check for interference from the parties. The main advantage of this invention is that the control system is supplied to control the clamping mechanisms of the tie rods used with the injection molding machines. Another advantage of this invention is that a control system is provided to be used with attachment mechanisms of the connection bar for the injection molding machines, whose mechanisms function to couple junction bars, provide clamping forces and also to provide Mold separation forces. Still another advantage of this invention is that a control and process system is provided which is operative with attachment bar fastening mechanisms to place them in the proper starting position after each molding operation so as to be Consistently sufficient movement for clamping and separating the mold. Still another object of this invention is that a control and process system is provided which is operative with link bar fastening mechanisms for adjusting the initial positions of the mechanisms to accommodate different mold sizes and derogatory closure heights. It should be understood that the invention is not limited to the illustrations described and shown in present, which are considered merely illustrative of the best methods for carrying out the invention and which are susceptible to modification in their form, size, arrangement of the parts and operation details. The invention aims rather to include all those modifications that are within the spirit and scope defined by the claims. Having described the invention as above, property is claimed as contained in the following:

Claims (54)

1. A fastening system for use with plates of a molding machine, characterized in that it comprises: means for connecting the plates; mobile means for positioning one of the plates on these means for connecting the plates and another of the related plates; and fixing / holding means for forcibly coupling one of the plates with another of the plates and on the means for connecting, for supporting the forced coupling of one of the plates with the other of the plates and the means for connecting, and to separate one of the plates from the other of the plates and connecting means.

2. The system according to claim 1, wherein one of the plates comprises a movable plate and the other of the plates comprises a stationary plate, further characterized in that it comprises: means for determining the adjustable starting position of the fixing means / clamping and a moving platen characterized in that the adjustable starting position provides a sufficient displacement for the moving platen for clamping and separating the mold; means for adjusting the adjustable starting position to achieve the highest accuracy of the adjustable starting position for the fixing / holding means and the mobile stage, the means for the adjustment include means for driving the fixing / holding means for developing the force securing the fixing / holding means; means for monitoring and controlling the position of the fixing / holding means and the mobile stage; and means for holding the clamping force at the recommended level between the mobile stage and the means for connection and the mobile stage and the stationary stage.

3. The system according to at least one of claims 1 and 2, characterized in that the fixing / holding means comprise means for fixing one of the plates to at least one of the connection means, characterized in that the fixing means comprise coupling means for positioning the fixing means inside and outside the closure coupling with at least one of the connection means in such a way that when the coupling means are outside the closure coupling with at least one of the means of connection, the fixing means and at least one of the connection means are relatively mobile.

4. The system according to at least one of claims 1 and 3, characterized in that it comprises: another of the plates comprising a stationary platen that includes at least one stationary mold half; one of the plates comprising a moving stage moving relative to the stationary stage and having a mold half adapted to engage the stationary mold half to form a first mold; a unit for providing the laundry to the first mold; and connecting means, which extend between the stationary platen and the mobile stage.

5. The system according to at least one of claims 1 and 3, characterized in that it comprises: another of the plates comprising a stationary platen, including at least two stationary mold halves, located at opposite ends of the stationary platen; the platen comprises a moving platen that moves in relation to the stationary platen and that presents a movable mold half, adapted to engage one of the halves of the stationary mold to form a first mold; another moving platen moving towards the stationary platen and includes another movable mold half adapted to engage another of the stationary mold halves to form a second mold; means for supplying the laundry to the first and second molds; means to further connect to extend between and connect to the stationary platen and the other mobile stage; characterized in that at least one of the movable plates, and the other movable plate and the stationary plate include one of the fixing / holding means and the means for fixing.

6. The system according to claim 2, characterized in that the fixing / securing means comprise a means of a member of the body having a structure which is movable as a simple unit for fixing the connection means and for transporting a clamping force to the platens, the means of a member of the body adapted to be joined with at least one of the platens and include fixing means and means of transport of the clamping force to the plates to hold the plates during molding.

7. The system according to at least one of claims 2, 3, 4, 5 and 6, characterized in that one of the fixing / holding means and the fixing means are rotated in and out of the coupling with at least one of the means of connection.

8. The system in accordance with the claim 7, characterized in that at least one of the connecting means includes a mating surface having protrusions or projections for coupling by the coupling means.

9. The system according to claim 8, characterized in that the coupling surface is a first toothed surface placed at one end of at least one of the connection means.

10. The system in accordance with the claim 9, characterized in that the fixing means comprise a means of a body member and a sleeve arranged coaxially in relation to at least one of the connection means, one of the sleeve and the body member which they include an internal toothed surface adjacent to at least one of the connection means and an outer surface, the internal toothed surface adapted to engage with the first toothed surface.

11. The system in accordance with the claim 10, characterized in that the first toothed surface is an outer surface located at one end of at least one of the connection means, the first toothed surface includes strips of outer teeth, the outer strips extend in an axial direction at least at least one of the connection means, each of the outer tooth strips are radially spaced apart from at least one of the outer tooth strips by means of axially extending outer grooves.

12. The system in accordance with the claim 11, characterized in that the inner toothed surface includes axially extending inner tooth strips, each of the inner tooth strips being radially spaced apart from at least one of the other inner strips by means of one of the inner slots which is they extend axially and characterized in that during the rotation of the means of the body member and the sleeve, towards the closing coupling with at least one of the connecting means, the inner tooth strips are coupled with the outer tooth strips and the inner grooves align substantially with the outer grooves and characterized by that during the rotation of one of the means of the body member and a sleeve, outside coupling As standard with at least one of the connecting means, the inner tooth strips align with the outer grooves and the inner grooves align with the outer tooth strips.

13. The system according to claim 12, characterized in that the internal grooves have a width that extends radially greater than the outer tooth strips and the outer grooves have a width that extends radially greater than the inner tooth strips.

14. The system according to at least one of claims 3, 4, 5 and 6, characterized in that the fixing means comprise a sleeve arranged coaxially in relation to at least one of the connection means, the sleeve includes an inner surface adjacent to at least one of the connecting means and an outer surface.

15. The system in accordance with the claim 14, characterized in that the coupling means are positioned on the inner surface.

16. The system in accordance with the claim 15, characterized in that the coupling means comprise a toothed surface.

17. The system according to at least one of claims 3, 4, 5 and 6, characterized in that the means for further moving the fixing means along at least one of the connection means when the fixing means is in place. outside the closing coupling with at least one of the connection means.

18. The system according to claim 17, characterized in that the movement means comprise a piston and cylinder assembly.

19. The system according to at least one of claims 3, 4 and 5, characterized in that the fixing means additionally comprise means for transporting a clamping force to the platens to hold the platens during molding.

20. The system according to at least one of claims 6 and 19, characterized in that the movable plates are adapted to be forced in directions to reach the clamping with at least one of the other moving plates and the stationary platen and characterized in that the movable plates have perforations for receiving the fixing means, the means for transport having an outer surface being configured to form cavities between the outer surface and one of the perforations and being configured to present surfaces that extend substantially transversely to the directions , characterized in that the cavities are for the introduction of pressurized fluid and the surfaces are for the reception of pressure of the pressurized fluid against them to move the movable plates in these directions.

21. The system according to claim 7, further characterized in that it comprises means for rotating the fixing means relative to at least one of the connection means for placing the coupling means inside and outside the closure coupling with at least one of the means of connection. 6b

22. The system in accordance with the claim 21, characterized in that the rotation means comprise an articulation assembly connected to the fixing means.

23. The system in accordance with the claim 22, further characterized in that it includes a plurality of synchronized articulation drive mechanisms for driving the articulation assembly to synchronously position the fastening means in and out of the closure coupling with at least one of the connection means.

24. The system according to claim 23, characterized in that each of the synchronized articulation drive mechanisms includes a piston and cylinder device connected with a plurality of articulated bars that form the articulation assembly to drive the articulation bars and that cause that the fixing means are placed in and out of the closure coupling with at least one of the connection means.

25. The system according to at least one of claims 5 and 6, characterized in that the unit it is movable in guides mounted on the molding machine and the unit further includes means for alternately closing the unit to the hot channels.

26. The system according to at least one of claims 1, 4 and 5, characterized in that at least one of the plates, the movable plates and the other movable plates include perforations in which the fixing means are mounted.

27. The system according to claim 2, further characterized in that it comprises means for disabling and enabling the fixing / holding means.

28. The system in accordance with the claim 27, characterized in that the means for disabling and enabling comprise a control valve for each of the fixing / holding means.

29. The system in accordance with the claim 2, characterized in that the fixing / holding means are actuated by pressurized fluid, the means for actuating comprise a multidirectional valve for directing the pressurized fluid to the fixing / holding means.

30. The system in accordance with the claim 29, characterized in that the means for monitoring and controlling comprise a closed circuit pressure controlling means for controlling the rate of increase of the clamping force by controlling the opening of the multidirectional valve.

31. The system in accordance with the claim 30, characterized in that the closed circuit pressure controller means includes logic means to determine the maximum allowable deviation in the relative position between a plurality of the fixing / holding means and to terminate the drive if the maximum allowable deviation is exceeded.

32. The system in accordance with the claim 31, which also includes means for measuring the linear position of each of the pluralities of the fixing / holding means, characterized in that the measuring means are operative with the logical means.

33. The system according to claim 2, characterized in that the means for determining an adjustable starting position and the means for adjusting comprise a controller with a means of a product of a OH computer program to determine the adjustable starting position.

34. The system according to claim 2, characterized in that the holding means comprise a shut-off valve operative to maintain the clamping force.

35. The system according to claim 28, further characterized in that it comprises means for rotating the fixing / holding means in engagement with the connecting means and means for determining the angular position of the fixing / holding means to obtain the proper alignment with the connection means.

36. The system according to claim 35, characterized in that the means for determining the angled positions comprise proximity switches located with the rotation means to detect a recommended angular orientation.

37. The system according to claim 33, further characterized in that it includes means for detecting the molded parts trapped in the mold halves.

38. The system in accordance with the claim 37, characterized in that the means for detecting comprise the controller that includes a product means of a computer program to work in conjunction with the means for monitoring and control.

39. The system in accordance with the claim 38, characterized in that the means of the computer program product comprises a means of the computer readable code for comparing the closing heights of the previous cycles in progress and determining a representative value, the potentially indicative value of a trapped part, characterized in that if the representative value satisfies a predetermined acceptable value, a part may be trapped and an indicator thereof is activated.

40. A process for controlling the mold activity of a molding machine having a movable mold half positioned on a moving platen and another mold half positioned on another platen, characterized in that it comprises the steps of: providing fixing / holding means and means for transporting the fixing / holding means, the fixing / holding means for placing the platens of the mobile mold on the means for transporting and relating to another platen, for forcibly engaging the moving mold platen with the other platen on the conveying means, for supporting the forced coupling of the platen of the moving die with the other platen and the transport means and for separating the moving platen from the other platen and means of transport; determining an adjustable starting position of the fixing / holding means and of the movable mold half, characterized in that in the adjustable starting position sufficient displacement is provided for the movable mold half to hold it and separate it; check after each clamping if the adjustable starting position is sufficient for proper clamping of the mold; adjust the adjustable starting position if necessary after the revision stage to achieve greater accuracy; actuating the fixing / holding means to develop a clamping force; providing means for developing the clamping force to the clamping / holding means for the driving step; monitor and control the poetry of the fixing / holding means; and maintain the force of rejection at the recommended level.

41. The process in accordance with the claim 40, characterized in that the step of determining the starting position comprises the steps of: measuring the maximum and actual closing height of the other stage and the mobile stage; define a relationship between the maximum closing height of the other stage and the moving stage, the actual closing height of the other stage and the moving stage, the passage of the medium and additional factors; and calculate the starting jot from the relationship.

42. The process in accordance with the claim 41, characterized in that the revision step comprises the steps of: re-measuring the maximum and actual closing heights of the stationary and mobile stage after each fastening; and recalculate the adjustable start position using the ratio and repetition of the determination step.

43. The process according to claim 40, further characterized in that it comprises the steps of disabling and enabling the fastening by the fixing / holding means and the confirmation of the condition of the fixing / enabling means as enabled and disabled, characterized in that the condition defines at least one condition that is detected before the driving stage.

44. The process according to claim 40, characterized in that the monitoring and control stage includes a closed-loop controller to determine a maximum allowable deviation in the relative positioning of a plurality of the fixing / holding means and the termination of the clamping process. if the maximum permissible deviation is exceeded.

45. The process according to claim 40, further characterized in that it comprises the steps of rotating the fixing / holding means for coupling them with the transport means and the determination of the angular position of the fixing / holding means for the proper alignment with the means of transport.

46. The process according to claim 42, further characterized in that it comprises the step of repositioning the fixing / holding means.

47. The process in accordance with the claim 46, characterized in that the repositioning step includes the steps of: rotating the fixing / holding means outside the coupling with the transport means; determining the angular position of the securing / securing means for proper alignment for decoupling with the transport means; and moving the fixing / holding means to the adjustable starting position.

48. The process in accordance with the claim 47, characterized in that the movement step includes: a general movement of the fixing / holding means along a distance to the starting position adjustable to a threshold position; and the fine movement of one of the fixing / holding means towards the starting jigsaw from the threshold position.

49. The process in accordance with the claim 48, characterized in that the movement step further includes: monitoring the distance of the fixing / holding means of the adjustable starting piece; discontinuating the movement of each of the fixing / holding means that reaches the threshold position when another of the fixing / holding means moves in a general manner; and continuing the movement of at least one of the fixing / holding means by means of the fine movement step when all other fixing / holding means have been stopped by means of the discontinuance step.

50. The process according to claim 47, characterized in that the movement step includes: general movement of only the first of the fixing / holding means along a distance to the adjustable starting position until a threshold position is reached; and fine movement of the first of the means of fixation / eviction from the threshold position to the adjustable starting position.

51. The process according to claim 50, characterized in that the movement stage also includes: disabling all the fixing / holding means while the first of the means of fixation / eviction moves in general and fine.

52. The process in accordance with the claim 51, characterized in that the movement step includes: enabling one of all the fixing / holding means, when the first of the fixing / holding means has reached the adjustable starting position; and repeating the general and fine movement stages for one of all the fixing / holding means.

53. The process according to claim 40, further characterized in that it includes the step of detecting the molded parts trapped in the mold halves.

54. The process according to claim 53, characterized in that the detection step comprises the step of: comparing the closing heights of the previous cycles and of course and determining a representative value, the value potentially indicative of a trapped part; Y 70 trigger an indicator if the representative value does not satisfy a predetermined acceptable value, so it indicates a possible trapped part.