DE1161682B - Vulcanizing press for retreading car tires - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: B 29 h

German class: 39 a6-5 /04

Number:
File number:
Registration date:
Display day:

1161 682
B 61285 X / 39 a6
February 15, 1961
January 23, 1964

In vulcanizing presses for retreading car tires with an upper and a lower one Heating table with applied or recessed mold halves, one made of threaded spindles and which can be screwed onto existing gears attached to the upper heating table for tight pressing Both mold halves and lifting from each other after vulcanization takes place Move the upper to the lower mold half and lift it again either by pressing the Threaded spindles by an electric motor or by a hydraulic one of the threaded spindles independent drive instead. In all cases, however, the tensioning and releasing of the tensioning takes place by hand by operating the threaded spindles, the z. B. in fixedly arranged on the upper heating table Nuts are screwable.

The disadvantage of the known designs is that for clamping both mold halves large torques are required due to the threaded spindles. After heating is complete, the Torques required to release the tension because of the torques that have occurred in the meantime Thermal stresses even greater. To generate the required torques are heavy and expensive Drives and transmission media required. If the press is not sufficiently preheated at the beginning of the shift, the torques required for opening can be so large that they of the Drive cannot be generated. The press remains closed. You have to wait several hours until it is cold.

By means of the invention, the disadvantages mentioned in broad outline are the ones mentioned above Avoided executions. The invention relates to the aforementioned type of vulcanizing presses the moving of the upper part of the mold to the lower part by a hydraulic drive and the The tensioning and releasing of the tensioning takes place by means of threaded spindles, which are in the upper heating table arranged nuts are rotatable.

According to the invention it is proposed that the nuts be designed as pistons of the hydraulic drive whose cylinders are firmly seated on or on the upper heating table.

The upper part is brought up here by the threaded spindles and in this position by the Self-locking of the threaded spindles held while bracing the mold halves on the smallest way takes place through the hydraulic drive, the pistons of which are the nuts.

The thread vulcanizing press for retreading is an advantageous development
of car tires

Applicant:

Brunotte & Niemeyer machine factory
Company with limited liability,
Hanover, Vahrenwalder Str. 226/228

Named as inventor:

Artur Pohl,

Langenhagen near Hanover

spindles on which the pistons can be screwed are pivoted on the lower heating table. The drive motor for the spindles is only made so large that it is able to support the weight of the To lift the upper part of the mold. It is not necessary that he be biased when closing the press generated. When the upper part of the mold by the motorized

he driven lead screw has been lowered and has placed itself on the lower part of the mold or the tire inserted therein, the motor will run through a switch is switched off, and a pressure medium acts on the pistons, which are designed as nuts, whereby the mold halves are firmly pressed together. The cross section of the designed as a piston The cylinder receiving the nuts is so large that the entire pressure of the circular heating hose can be compensated. It also compensates for any uneven thermal expansion that occurs during the Vulcanization occurs in the lead screws and the mold halves. When the press is opened, not only the hydraulic pressure under the pistons, which are also spindle nuts, is released, Instead, pressure is applied to the other side of the piston, which separates the mold halves completely from one another separates and enables the upper mold half to be lifted off with the least amount of force can be.

In the drawings, an embodiment of the vulcanizing press is shown schematically. It shows

Fig. 1 the closed press in side view with a cut hydraulic cylinder together with a nut designed as a piston,

Fig. 2 the press of Fig. 1 in the open State,

309 780/196

Fig. 3 is a section through the closed press seen from and

Fig. 4 is a plan of the closed press.

According to the embodiment, the lower mold half 1 is clamped on the lower heating table 2, which stands with a base 3 on the ground.

The upper mold half 4 is clamped onto the upper heating table 5. Furthermore is on the upper heating table 5 a cylinder 6 is screwed on each side, in which a piston 7 is axially displaceable. the Pistons sit with internal threads on threaded spindles 8. The pistons 7 are sleeve-like Ends 9 passed through glands 10 of cylinders 6. The threaded spindles 8 are pivotable stored on the lower heating table 2. For this purpose, the threaded spindles 8 each sit in one Guide bearing 11, which is rotatably mounted with lateral pins 12, 13 in bearings 14, 15. The camps 14 sit in the lower heating table 2, while the bearings 15 are attached to brackets 16 of the lower heating table 2 are.

The weight of the upper heating table 5 with the upper mold half 4 is carried by the threaded spindles 8 seated annular shoulders 17 on thrust ball bearings 18 and transferred through these via the guide bearings 11 to the lower heating table 2. At the lower end 8 threaded nuts 19 are screwed onto the threaded spindles, which on the upper heating table 5 exerted circular heating hose internal pressure on the guide bearing 11 and thus on transfer the lower heating table 2. They are secured against rotation by pins 23 and point Toothed rims 24, which via endless roller chains 26 with two on the shaft of a drive motor 20 seated sprockets 25 are coupled.

The threaded spindles 8 are driven jointly by the drive motor 20, which is driven by a gear, z. B. a chain drive with the spindles 8 is coupled.

The drive motor 20 is attached to a swivel frame 21, which is supported by a cover 36 on pins 22 of the guide bearing 11 is clamped.

To improve the accessibility to the press and to roll out the tire from the To enable shape, the threaded spindles 8 by one of a cylinder 27 with a piston 29 existing hydraulic drive can be pivoted backwards at an angle.

The details of the oil hydraulics, such as pumps, control slides, etc., have been dispensed with. as they are well known.

To close the press - as Fig. 2 shows - by actuating the oil-hydraulic Control organs pressurized oil conveyed through a line 34 into the upper half of the cylinder 27, while the lower half is in communication with a line 28, whereupon the piston 29 naoh moved down. Since the cylinder 27 is articulated to the swivel frame 21 by a bolt 38, This piston movement causes the threaded spindles 8, which carry the "upper heating table 5," through Pivoting about the rotatably mounted guide bearing 11 brought into the vertical position. The When the vertical position is reached, a switch 30 is actuated by the swivel frame 21 and sets the drive motor 20 in operation. The pistons 7 move down and with the threaded spindles 8 them the upper heating table 5. During this process, the inside of the upper cylinder cover 39 is the Cylinder 6 on the upper side of the piston 7. As soon as the upper mold half 4 and the lower Touch mold half 1 on the partial surface or the upper mold half 4 on the inserted tire sets without touching the lower mold half 1, the upper heating table 5 remains with the upper mold half 4 stand and the pistons 7 move

ίο in the cylinders 6 and on the threaded spindles 8 downwards until their lower sides rest on disc springs 37, those on the inner side of the lower Cylinder cover 40 of the cylinder 6 are located. At this moment an electrical switch 31 is through the ends 9 of the pistons 7 are actuated and the drive motor 20 is switched off. Now is done by hand or automatically, e.g. B. by pulse from the electrical switch 31, pressure oil through a line 32 the The lower cylinder halves of the cylinder 6 are supplied.

As a result, the pistons 7 push themselves slightly upwards in the cylinders 6, thereby tensioning the mold halves 1 and 4 tightly together and keep them tightly closed against the internal pressure of the circular heating hose. If the press is to be opened, it is first carried out manually or automatically, e.g. B. by program clock, the pressure oil drained from the lower cylinder halves of the cylinder 6 and pressure oil their upper Cylinder halves fed through a line 33. As a result, the pistons 7 move downwards and lift the bracing of the upper mold half 4 with the lower mold half 1 again. So now with There is certainly a gap of 8 to 10 mm between the upper mold half 4 and the lower mold half 1 arises at the parting line, the pistons 7 press the disc springs 37 together so that the upper half of the mold 4 is lifted from the lower mold half 1 by the amount of spring compression. Through this it is achieved that the tire is already released from the mold. The drive motor 20 has so when opening the press only has to overcome a torque equal to the weight of the upper heating table 5 and the upper mold half 4 corresponds. The disc springs 37 are dimensioned so that they when Address closing the press only slightly.

After the pistons 7 have reached their lowest position, is manually or automatically, for. B. by Impulse from the electrical switch 31, the drive motor 20 is put into operation in the opposite direction of rotation, so that the upper heating table 5 spindles on the thread so 8 migrates upwards. Simultaneously receives the upper half of the cylinder 27 by hand or automatically through line 34 pressurized oil. Of the The piston 29 now presses the swivel frame 21 downwards, and as a result the threaded spindles 8 swivel with the upper heating table 5 to the rear. The drive motor 20 is at the end of the upward movement turned off by a switch 35.

Claims (10)

Patent claims: 1. Vulcanizing press for retreading car tires with one top and one Lower heating table with placed or embedded mold halves, one made of threaded spindles and thereon screwed nuts attached to the upper heating table for firmly pressing both mold halves together and lifting them off from each other completed vulcanization and a hydraulic Drive, characterized in that the nuts as pistons (7) of the hydraulic Drive are formed, the cylinder (6) sit firmly on or on the upper heating table (5). 2. Vulcanizing press naoh claim 1, characterized in that the threaded spindles (8) on which the pistons (7) can be screwed, mounted pivotably on the lower heating table (2) are. 3. VuJkanisierpresse according to claims 1 and 2, characterized in that on the threaded spindles (8) one on the lower heating table (2) mounted swivel frame (21), which has a drive motor (20) for the rotary movement the threaded spindles (8) carries. 4. Vulcanizing press according to claims 1 to 3, characterized in that the pivot frame (21) is connected to a hydraulically operated cylinder (27) which is attached to the lower Heating table (2) is mounted. 5. Vulcanizing press naoh claims 1 to 4, characterized in that the cylinder (27) has a piston (29) engaging with its piston rod on the lower heating table (2). 6. Vulcanizing press according to claims 1 to 5, characterized in that the ends the piston (7) protrude from the cylinder (6) on both sides and have approaches for controlling of switches (31, 35) for switching off the drive motor (20) when the upper one is swiveled out Have the mold half (4) together with the upper heating table (5) and with the clamped mold closed. 7. vulcanizing press according to claims 1 to 5, characterized in that the pivot frame (21) a switch (30) for the drive motor (20) in the case of an essentially vertical Position of the threaded spindles (8) is assigned. 8. Vulcanizing press according to claim 6, characterized in that the switch (31) as a pulse switch for the drive motor of a pressure oil pump for supplying pressure oil to the cylinders (6) is formed. 9. Vulcanizing press according to claims 6 and 8, characterized in that the switch (31) is designed as a switch for the drive motor (20) for opening the mold. 10. Vulcanizing press according to claim 1, characterized in that in the lower half the cylinder (6) is seated by a plate spring (37) which can be compressed by the piston (7). Considered publications:
British Patent No. 599,732;
U.S. Patent No. 2,745,137. For this purpose 2 sheets of drawings 309 780/196 1.64 © Bundesdruckerei Berlin