WO2000038907A2 - V-belt drive for diverting a vertical force of pressure - Google Patents

Abstract

The invention relates to a V-belt drive for diverting a vertical force of pressure. Said V-belt drive comprises a drive (1), a slide (2) and a slide guide (3). It is characterized in that the slide surfaces (8) in which the slide (2) is guided are arranged in the shape of a prism and in that the slide (2) is returned by way of a pneumatic spring which is arranged in the slide.

Description

 Wedge drive for deflecting a vertical pressing force

The object of the invention is a wedge drive for deflecting a vertical pressing force with a driver 1, a slide 2 and a slide holder 3. A preferred object is a horizontal wedge drive.

Wedge drives are devices that are used in the automotive industry to machine body parts. The metalworking of body parts and other parts is carried out today in industrial continuous processes. This means that the metal parts have to be manufactured, shaped, punched and machined in a continuous workflow. A large number of different presses, punches and other devices for metalworking are frequently used here. Tools specially made for the body parts and in which wedge drives are installed are used in these presses. The wedge drives process the body parts at any point on the metal part. The wedge drive deflects the vertical working direction into a horizontal working direction in order to be able to carry out lateral operations on body parts if necessary. During this processing, considerable forces act permanently on the wedge drives used. Usual presses work with pressures from 100 t to over 2000 t. In a continuous machining process of the metal parts, these forces are permanently loaded on the wedge drives used. The wedge drives must therefore be designed for such an application so that they can withstand these forces for as long as possible without any signs of wear and tear, and furthermore a reproducible, precisely fitting processing of the metal parts is made possible.

When the wedge drive is installed in a press, the slide 2 is installed in the lower part of a press tool. In The driver 1 is rigidly mounted on the upper part of the tool. When the driver 1 is moved downward, it drives the slider 2, which is in the retracted position, over the slide guide 3 with the wedge bevel of the driver 1 when it sits on the slide 2. When the tool is completely moved together, the slide 2 has reached its end position. The slide is thus able to carry out certain operations such as punched holes on body parts by means of the deflected pressing force. After completion of the work step, the upper part of the tool moves up and gives the slide 2, which is pulled back by a gas spring, the possibility to return to its original position. Thanks to the use of maintenance-free sliding elements, the slider is still able to transmit enormous press forces even after long running times. The high pressures are absolutely necessary in the automotive industry for the production of body parts. They can vary depending on the thickness of the processed sheet.

Various wedge drives are known from the prior art. For example, DE 26 40 318 AI describes a wedge drive for diverting a vertical pressing force into a force acting at an angle for the forming process. This wedge drive consists of a driving wedge on which a vertical force of a corresponding working press acts and a sliding wedge which transfers the force to the horizontal. The driver wedge and the slide wedge either run over a rounded cooperating area or, in a further embodiment, over a roller.

Wedge drives known from the prior art have such great disadvantages that they have for the most part not been released for production by the automotive industry. It is therefore still necessary that such wedge drives as One-of-a-kind products must be manufactured. Such custom-made products are cost-intensive and can usually only be used in a special location for which they were designed. Spare parts have to be manufactured individually, so that this fact is also associated with great expenditure of time and money.

Another disadvantage is that the wedge drives on the market according to the prior art have slides which have almost no interchangeable sliding elements and therefore have to be replaced completely in the event of maintenance. The running accuracy can only be guaranteed by incorporating the slide. This incorporation is extremely complex and expensive, since the running accuracy must be in the range 0.01 mm.

Due to the enormous pressing forces that a wedge drive must transmit, the guides of the wedge drive are always subject to a certain amount of wear. With conventional designs of wedge drives, this wear has an immediate effect on the running accuracy of the slide. Furthermore, repair of a worn-out wedge drive is not possible due to the lack of replaceable sliding elements. They must therefore be exchanged for new ones, which is extremely uneconomical.

Another disadvantage is that the pressure generated by the driving wedge screwed in the upper part is intercepted on a plate screwed to the slide bed. However, since the pressing forces can amount to several tons, the fastening screws of the interception plate are in no case able to absorb these forces. Due to its strength, the interception plate itself is not able to intercept the thrust that occurs. The slide return, which is achieved via a steel spring, does not have a high life expectancy. The steel spring breaks soon after it is used in continuous industrial processes. The result of this is that the slide can no longer be pushed back, so that inevitable damage to the tool occurs. The restoring forces generated by the steel spring are generally not sufficient to push a possibly jammed slide back into its end position, which in turn can damage the tool.

Another disadvantage of the wedge drives known from the prior art is that the known wedge drives do not have a mounting plate for building up the punching normal. This makes the incorporation and operation of the slide considerably more expensive, since the individual punching standards can be assembled with the entire disassembly of the entire slide. It is not possible to replace the punches in the installed state. Furthermore, there are no measuring bores, so that the exact position of the standard parts can only be checked with great expenditure of time and effort. Special aids are often necessary to be able to check the situation in the first place.

The screw-on surfaces for punching standards are far too small for almost all known slides. For example, it is not possible to install a steel scraper in addition to a punch with the corresponding holding plate. However, this entails considerable design disadvantages for the production of body parts, since the rubber wipers used to date, which have to be serviced relatively frequently, do not result in a long service life. Another disadvantage ... is that the replacement of the puckholder spring in the installed state Γ Γ is due to the complete removal of the wedge neos, // as it results in a long maintenance phase and machine downtime.

Because of this design deficiency, wedge drives known from the prior art are not able to achieve high press pressures and service lives, such as are required for forming sheet metal parts, for example. The result of this is that, in general, the slides produced in the prior art are not used in sheet metal processing, but rather that one-off production takes place for each use of a wedge drive.

It was therefore the technical object of the invention to provide a wedge drive which does not have the disadvantages described above and which can be produced in a continuously industrial production process with the longest possible service life and cost-effective use.

This technical problem is solved by a wedge drive, which is characterized in that the slide surfaces 8, in which the slide 2 is guided, are arranged in a prism shape and the slide return is carried out by means of a gas pressure spring 5 arranged in the slide 2.

With the m prism shape arranged sliding surface it is achieved that the driver 1 always pushes the slider 2 into the slider bed during the operation. In this way, the slide 2 is guided in its direction of movement over the sliding plates 8 that rise sideways. This has the effect that the manufacturing tolerances have no influence on the running accuracy of the slide 2. Furthermore, the shooter can also handle thrusts that occur to the side without affecting his accuracy. In addition to the prisms arranged in the lower part The angle rails used ensure maximum lateral support.

The use of gas pressure springs as slide return as an alternative to steel springs has the following advantages. High thrust forces are achieved so that the slide 2 is pushed into its initial position in any case, even if the slide is jammed. This prevents damage to the tool. The use of gas pressure springs also guarantees a long service life, since the gas pressure springs have a considerably longer service life than the return springs made of steel used previously. Furthermore, the installation conditions when using gas pressure springs are so favorable that a compact design is possible and thus a

15 large area of application for the operation according to the invention in the field of automobile construction is made possible.

The gas pressure spring can be removed in the tool when installed. It is closed by a plug, which

20 is screwed into the slide from behind. This has the advantage that an old and used gas pressure spring can be changed easily and quickly with little effort. The stopper is easily in the retracted position of the slide through a mounting hole in the rear part

25 to remove the slide bed, so that when the slide is then pushed forward by hand, the gas pressure spring can be removed easily accessible through the same hole.

Changing the slide return when the wedge drive is installed has the following advantages. Maintenance times are reduced to a minimum and damage to the wedge drive during installation and removal can be avoided. The use of commercially available gas pressure springs reduces inventory at the end customer. The so far from the state of the art> ■. known wedge drives have an inserted spring return train, which is arranged sc, that it can only be changed by dismantling the entire cell drive and dismantling it. Thus, in the wedge drive according to the invention, a gas pressure spring can be changed in a fraction of the time otherwise required for the keel drives of the prior art.

In the automotive industry, wedge drives today require a service life of around 1 million strokes. Steel springs generally allow a service life of between 250,000 and 300,000 strokes, but gas springs, with the appropriate installation, enable around 1 million strokes. As already mentioned above, the maintenance work on wedge drives with retaining springs is about 4 times higher than the maintenance work on the wedge drive according to the invention, quite apart from the much more advantageous service life. In addition, in the wedge drive according to the invention, only the protective plate and the sealing plug have to be milled in order to remove the gas spring. In the case of the products of the prior art, the entire device has to be dismantled and dismantled from the pressing tool, since the inside of the spring is located at a location that is not accessible from the outside.

In a preferred embodiment, a mounting plate 4 is arranged on the slide 2. This can preferably be removed using fastening screws that are accessible from the rear. This enables the punching and forming standards built on the mounting plate to be easily installed and removed even when the wedge drive is arranged in the tool. The construction of the punching standards is also easier and faster to accomplish on a separate right-angled mounting plate than on the slide 2 itself.

The use of the mounting plate makes it possible, for example, to replace broken punching standards in the installed state under the press. This means that if, for example, a punch should break during part 1 production, it can be replaced quickly and easily by completely removing the mounting plate. In contrast to this, the wedge drives currently known from the prior art and available on the market are constructed in such a way that the entire wedge drive must be dismantled in any case, because the space in front of the punches is in any case so small that it is not sufficient To loosen screws and pins. A change under the press can therefore not take place, ie the entire press tool, which weighs about 40 t, must be removed from the press just to change the punch.

Another advantage of the wedge drive according to the invention with a mounting plate is obtained during the initial assembly, for example, of punches. This can be done on a rectangular Montageis plate outside the actual wedge drive much easier than with the products of the prior art, wherever it must be mounted directly. Since there is always a driver slope at the rear of a wedge drive, it is often only possible with additional devices to insert various screws and pin holes for fastening the corresponding punch holder plates. In the case of a mounting plate, the screw-on surface runs parallel to the base, i.e. the mounting holes can be attached easily and without additional tools. This fact significantly reduces manufacturing costs.

Since the installation conditions in press tools vary widely, it is a great advantage if a wedge drive can adapt to the conditions in the press tool. Wedge drives of the standard

30 of the technology that are manufactured in series are mostly not applicable in such areas. A mounting plate that can be individually adapted by the customer to the conditions in the tool is very well able to remedy the situation. This increases the area of application of the known

! _' . Wedge drives in press tool manufacture considerably. The costly changing of the punch, for example, in the wedge drives according to the state of the art in Tecnnik also means that if a tool has to be removed from a composite, the entire part production on these press lines comes to a standstill. The removal and installation plus the replacement of the broken punching standards can quickly take several hours in which not a single part can be manufactured. However, changing a mounting plate only takes a few minutes. There is no need to point out the costs of such maintenance in the fully automatic parts production of an automobile manufacturer.

In a further preferred embodiment, a cast shoulder 13 is arranged on the side of the slide guide 3 to compensate for the forces acting on the driver 1. When the press transfers the pressure to the driver 1, considerable forces occur on the driver. Due to the preferably used cast shoulder on the slide bed, the upper part of the driver 1 in the slide bed is intercepted by a massive cast shoulder 13 against the working pressure h. Due to its massive construction, the cast shoulder 13 is able to completely absorb horizontal forces that occur during the work process. So there is no thrust from the upper part to the lower part of the wedge drive and an exact tool guidance is guaranteed. The cast-on solid cast shoulder is designed in such a way that it can fully absorb the shear forces occurring during the working stroke of the slide. Without this shoulder, the slide is unable to exert the pressing forces required by the auto industry. This means that sliders that do not have a solid cast shoulder, but only a screwed-on shoulder, are definitely not approved for production. Slides previously available on the market do not have a cast shoulder, but only screwed-on plates. So you can't even get the Generate half of the pressing forces generated by the wedge drive according to the invention.

In a further preferred embodiment, 13 sliding elements 6 are arranged on the shoulder. These sliding elements are preferably made of bronze with the appropriate solid lubricant. The use of these maintenance-free sliding elements increases the service life and reduces the maintenance costs of the wedge drive according to the invention to a minimum. These sliding elements can also be replaced without changing the entire wedge drive. In a further preferred embodiment, at least one measuring bore is arranged in the side flanges of the slide 2 as a reference and measuring point. The slide 2 is built completely over this bore so that it can be ideally measured and placed in the design drawing using CAD or manual methods. With this measuring hole, the build-up of standard parts on the work surface can easily be measured from the outside.

In a further embodiment, at least one keyway 15 is arranged in the mounting plate 4. The introduction of such a keyway makes it possible for the thrust which arises in the case of punching and form normalies built up on one side to be transferred ideally to the slide 2. This means that the fastening screws only have to perform a pure holding function without being exposed to lateral thrust.

In a further embodiment, a damping element 11 is arranged on the slide 2 in order to intercept the retracting slide. This damping element 11 is preferably made of rubber.

This measure increases the service life and in particular reduces the noise development when the wedge drive according to the invention is used in a tool. The wedge drive according to the invention furthermore has a slide guide 3 which is machined from all sides around it. This makes it possible to let the wedge drive rest on the tool, no matter which side. In this way, the wedge drive can be placed in particularly narrow tool areas against objects existing for constructional reasons, which would otherwise not be possible due to the imprecise external dimensions of the wedge drive.

10

It is further preferred that the slide guide 3 in the upper region has two oppositely arranged w edge strips 9 which clasp the slide 2 so that it can only be moved in the working direction. These heating strips 9 are preferably designed as sliding elements.

In order to generate an ideal pressure absorption from the press via the driver to the slide, it is further preferred that the guide surfaces, as seen from the vertical, overlap almost completely between the slide guide / slide and slide / driver. This is achieved in that the travel X of the slide 2 on the slide guide is greater than the travel Y of the slide 2 on the driver 1. In a further preferred embodiment, the angle between the 5 travel X and Y is 45 to 70 °, preferred 50-70 ° and particularly preferably 55-60 ° and the ratio between X and Y 1.5: 1. The ratio of travel X to travel Y is particularly preferably at least 1.5: 1.

o The following figures should explain the slider in more detail

FIG. 1 shows a cross section of the wedge trie according to the invention. The driver 1 has an upward screw flange with which it can be mounted on the upper part of a press tool. To the rear, a sliding element 6 is provided vertically to intercept the thrust generated by the driver slopes. This driver surface, which is fitted with a bronze sliding plate with solid lubricant, has an angle which is able to push the actual slide 2 forward. The slide plate is seen upwards, i.e. in the direction of thrust, intercepted against a cast shoulder. The slide 2 runs in the lower guide area on two prismatic sliding elements 8, which are also made of bronze with solid lubricant. These are deep in the central area and sloping upwards in the outer area.

15 This creates space in the middle area between the sliding plates for the slide return, which takes the form of a gas pressure spring 5. The gas pressure spring is able, on the one hand, to use a sealing plug 16 which is screwed into the slide 2 from behind

20 against the slide guide 3 and on the other hand to press against the plug 16 so that the slide 2 is always pushed backwards. At the back of the slide, a counterbore is provided for receiving a damping disc 11, which softens the retracting slide 2 against the slide guide 3

25 intercepts. The surface of the driver 1 is made according to the driver plate in the upper part to the number of degrees, so that it can absorb the entire pressure to be transferred to the press. The slope was designed so that the slide 2 to be driven is slightly slower than the driver 1 in the upper

30 parts running. A mounting plate 4 is mounted on the front of the slide 2. This was shouldered against lateral thrusts with the help of a T-shaped groove 17 (not shown). The mounting plate 4 is screwed from behind with generously sized fastening screws, so that one

'. *. no matter what was built on the front of the mounting plate 4, can be dismantled in the press when it is in the installed state. Two measuring bores 14 are arranged laterally in the slide 2, with the aid of which measuring or the construction of the slide in the tool can be traced. The slide guide 3 5 contains the counterpart to the lower guide of the slide 2, which follows two sliding plates 8 (not shown) arranged in prismatic form. The upper slide guide takes place with the aid of two opposing heating strips 9 which clasp the slide 2 in such a way that it can only be moved in the working direction. Here too, bronze sliding plates with solid lubricant are used. A surface was milled into the front of the slide guide 3, against which the gas pressure spring 5 is braced for returning the slide. In the rear part of the slide guide 3 there is a massive cast shoulder 13, 5, which in turn is equipped with a sliding plate made of bronze with solid lubricant 6. This shoulder 13 serves to absorb the thrust forces occurring during the work step, the driver 1 located in the upper part being supported against it. The slide guide 3 is mounted with four generously dimensioned fastening screws in the lower part of the tool. All outer edges of the slide 2 have been completely machined so that all the outer surfaces for contacting or also for absorbing various thrust forces, which can occur depending on the working method, can be transferred 5 to the lower part of a tool. At the back of the cast shoulder 13 there is a mounting hole which enables the gas pressure spring 13 to be removed through the shoulder. The gas pressure spring 5 inserted in the fever presses with its piston rod against milling in the front part of the slide guide. At the back, the bottom of the gas pressure spring presses against the sealing plug 16 located in the slide 2. By pushing the slide 2 forward, the gas pressure spring is compressed and, when moved apart, ensures that the slide 2 is in any case pushed back into its rest position. The gas pressure spring 5 is completely relieved in the rest position of the slide and thus ensures that the slide damping, which intercepts the retracting slide 2 against the slide guide 3, only has to take over the actual swing of the slide 2. The completely relieved gas pressure spring can be easily installed and removed through the mounting hole in the shoulder without the risk of spring preload pressing a holding element.

The mounting plate 4 on the front of the slider is used to build up the punching or forming standards. The mounting plate 4 was designed to be removable so that the assembled parts can be exchanged easily and quickly in a tool in the installed state of the slide 2. The mounting plate 4 was equipped with a T-shaped keyway 15 (not visible) to accommodate any side thrusts that may occur. The mounting plate 4 is screwed from behind so that the front screwing surface is not interrupted by the fastening screws.

FIG. 2 shows a three-dimensional view of the wedge drive according to the invention with the driver 1, the slide 2, the massive cast shoulder 13 and the angle strips for the slide guide 9.

Figure 3 shows a front view of the wedge drive according to the invention. The number 8 shows the lower sliding element for the slide guide on which the slide 2 is moved. The number 9 designates the angle bar for the slide guide, which enables a straight, directed movement of the slide. Finally, the number 16 denotes the sealing plug. After removing this plug, the gas pressure spring 5 can be replaced through the opening. Reference list

driver

pusher

Slide guide

Mounting plate

Gas pressure spring

Shoulder slider

Sliding element slide lower sliding element slide guide

Angle bar slide guide

adjusting spring

Damping element

Screw

shoulder

Measuring hole

Keyway mounting plate

Sealing plug

Mounting hole slide

Claims

claims 1. Wedge drive for deflecting a vertical pressing force with a driver (1), a slide (2) and a slide guide (3), characterized in that the sliding surfaces (8), in which the slide (2) is guided, arranged in the form of a prism are and the slide return by means of a gas pressure spring (5) arranged in the slide (2). 2. Wedge drive according to claim 1, characterized in that on Slider (2) a mounting plate (4) is arranged. 3. Wedge drive according to claims 1 or 2, characterized in that on the slide guide (3) laterally one Cast shoulder (13) is arranged to compensate for the forces acting on the driver (1). 4. Wedge drive according to claims 1 to 3, characterized in that on the shoulder (13) sliding elements (6) are arranged. 5. Wedge drive according to claims 1 to 4, characterized in that sliding elements made of bronze with solid lubricant are used. 6. Wedge drive according to claims 1 to 5, characterized in that in the side flanges of the slide (2) at least one measuring bore is arranged as a reference and a measuring point. 7. Wedge drive according to claims 1 to 6, characterized in that in the mounting plate (4) at least one keyway (15) is arranged. 8. Wedge drive according to claims 1 to 7, characterized in that a damping element (11) is arranged on the slide (2) to intercept the retracting slide 5 gen. 9. Wedge drive according to claim 8, characterized in that the damping element (11) consists of rubber. 10 10. Wedge drive according to claims 1 to 10, characterized in that the slide guide (3) in the upper region has two oppositely arranged angle bars (9) which clasp the slide (2) so that it can only be moved in the working direction. 15 11. Wedge drive according to claim 10, characterized in that the angle strips (9) are designed as sliding elements. 12. Wedge drive according to claims 1 to 11, characterized gekenn0 that the travel X of the slide (2) on the driver (1) is greater than the travel Y of the slide (2) on the slide guide (3). 13. Wedge drive according to claims 1 to 12, characterized marked 5, that the angle α between the travel X and travel Y is 45 to 70 °.