DE1250227B - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

PATENT LETTERING

Int. a .:

B 65 h

German KL: 47k -1/04

Number: 1 250 227

File number: N 23416 IX c / 47 k Filing date: July 4 , 1963

September 14, 1967
March 28 , 1968

Release day: Issue date:

The patent specification corresponds to the patent specification

The invention relates to a device for the step-by-step feeding of strip-shaped or strand-shaped material, for example for the step-by-step feeding of a metal strip to a press.

A device for the step-by-step advancement of wire is already known, which is provided with a stationary and with a crank drive. and moveable gripper for wire feed. The stationary gripper holds the Wire tight while the movable gripper executes the return stroke in the open position. The operation of the The clamping jaw of the moving gripper takes place via a cam disk rotating with the crank pin, which moves back and forth with the gripper accordingly. The arrangement is such that the clamping jaw is opened or closed via a linkage in a direction normal to the crank drive axis. is closed. The cam disk rotating with the crank pin has a circumferential surface of different radius, which cooperates with a motion decrease roller, which on a lever is provided on which one extending substantially along the connecting rod Control rod is hinged. This control rod is articulated at its other end with a lever arm as connected to actuate a pivot cam through which the jaw of the movable gripper is opened or closed. This known linkage and lever transmission for actuating the The jaw of the gripper is complicated and also expensive, since the individual components with the largest Accuracy must be made so even at high working speeds with which modern presses, punching and the like work, the necessary synchronization between the high- Leistungsmaschinc and the feeding device is given. In addition, it is also at the greatest Manufacturing accuracy of the linkage and lever transmission to fear that as a result of the large Inertia or mass forces, especially at high working speeds, vibrations and Shocks occur, so that the briefly to be opened and closed jaw dem prescribed interaction of movements no longer follows synchronously.

There is also a device for gradually feeding a metal strip to a press known, which is also with a stationary and a by a crank mechanism reciprocated gripper works. In this known device, the The jaw of the moving gripper is opened in the direction of the axis of rotation of the crank drive or device for incremental feeding of ribbon or strand-shaped material

Patented for:

Norton Tool Company Limited, Horley, Surrey (UK)

Representative:

Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Puls and Dr. E. v. Pechmann, patent attorneys, Munich 9, Schweigerstr. 2

Named as inventor: Henry Norton, Hubert Veare Norton, Leslie Buckingham Norton, Douglas Edwin Norton, Horley, Surrey

(Great Britain)

Claimed priority:

Great Britain 4 July 1962 (25 693)

closed. Here, no cam disk rotating with the crank pin is provided for actuating the clamping jaw of the gripper, which is moved back and forth along a straight guide, but rather carries it the end of the connecting rod connected to the gripper has a sleeve with an internal thread, which corresponds to the movement of the connecting rod around its Axis is pivoted back and forth. A threaded bolt is screwed into the sleeve, which has a Schtitzverbindungen is connected to the jaw with a certain amount of play, so that it is alternately opened and closed. The disadvantage of this device is that the time at which the moving gripper closes and thus the point at which the metal strip is gripped and the feed length are not precisely defined because the strip is on the forward stroke of the gripper is detected, with slight unevenness of the strip or differences in the strip thickness causing displacements. Also a different one Friction between the metal strip and the gripper at the beginning of closing leads to uneven feed steps. This is also known

809 531 / M9

1

Device to fear that the threaded connection between the swivel sleeve and screw bolt to abrasion and comparatively quickly leads to a game of movement, causing a shift in the point of attack and inaccuracies be evoked. Therefore, this device also does not meet the requirements placed on a feed device of the type mentioned at the beginning places are.

The invention is based on the object of providing a feeding device in a simple manner to train that it can be used in conjunction with high-performance machines and advances the goods to be fed in exactly the same steps.

According to the invention, the device for the step-by-step feeding of strip-shaped or strand-shaped Good with a gripper that can be moved back and forth by a crank mechanism with a clamping jaw that extends over a cam rotating with the crank pin and a linkage that interacts with this can be moved synchronously to the gripper movement into the open or closed position, characterized in that when the movement is known per se Clamping jaw in the direction of the axis of rotation of the crank drive, the cam surface on one face of the Cam formed and the linkage with a perpendicular to the axis of rotation of the crank tricbs The pivot axis is mounted on the connecting rod double lever, one end of which cooperates with the cam surface and the other end with the jaw is connected.

This training avoids a large number of moving, uniervvotfener parts and wear is fully functional even at high working speeds, whereby the opening and closing of the Gripper takes place exactly at the predetermined time or at the intended location.

In an advantageous development, the double lever is in a longitudinal slot in the connecting rod arranged. In this way, the lever as well as its pivot axis is against damage or Bending protected. Furthermore, there are improved structural possibilities for the arrangement of the cam disk and their interaction with the double lever.

As part of a further development it is provided that a roller resting against the cam surface is mounted on the end of the double lever which interacts with the cam surface, the Lagerachsc extends in the longitudinal direction of the double lever. This arrangement proves to be useful when using a motion take-off roller because it leads to a simple design.

With a known design of the feed device with a second stationary gripper with a Clamping jaw, which has a second cam rotating with the axis of rotation of the crank drive and a with this cooperating second linkage can be moved into the open or closed position it is advantageous if the jaw of the stationary gripper in the direction of the axis of rotation of the Crank drive is movable into the open or closed position and the cam surface on one end face of the second cam and the second rod is a double lever, one end with the cam surface of the second cam cooperates and its other end with the jaw 227

the stationary gripper is connected. This simple training means that the jaw the stationary gripper is precisely controlled and allows high working speeds.

The invention is explained in more detail below with reference to schematic drawings using an exemplary embodiment.

F i g. Fig. 1 shows the feeding device in use with a hydraulic press in a front view;

F i g. FIG. 2 shows the feeding device on an enlarged scale in plan when viewed in FIG Direction of arrow II in F i g. 1;

FIG. 3 shows the left end of the feed device according to FIG. 1 when viewed in the direction of the arrow III in Fi g. 1;

Fig. Fig. 4 is a vertical section through the feeding device along the line IV-IV in Fig. 1;

F i g. Figure 5 is a horizontal section through the feeding device along the line V-V in Figure 1;

F i g. 6 shows, on an enlarged scale, details of the crank and the associated cams when viewed in the direction of arrow VI in FIG. 5.

F i g. 1 shows a press 1 with a frame 2 as support for a press table 3 carrying a die 4. The press comprises a head 5 in which the device for raising and lowering the press ram 6 is arranged.

To give an example of the use of the device according to the invention, the Press with regard to its use for producing nasal disks from a metal strip 7 is described. The first performed on the strip 7 The operation consists of punching out the central hole of the disc; this is done with the help of an am Press punch 6 attached punch 8. Then the strip is advanced by one step, and the next hole is made with the help of Stamp S stamped into the strip. At the same time, the hole that has the first punched hole will be Nose disc with the help of a also attached to the ram 6 second tool 9 from the Punched out strips. The lower end of the tool 9 carries a guide pin 11 with a rounded lower end, and when the ram moves down, the guide pin engages in the first punched hole around the To bring the strips exactly in the right position, so that the hole is exactly concentric to the edge of the punched disc. On one side of the The feed device 12 is attached to the press. It is arranged on a supporting structure that comprises an upright rectangular plate 13, which with the press by not shown here Clamping member is connected; these clamping members make it possible to change the height of the feed device with respect to the table of the press. At right angles to this first plate 13 extends a second, also vertically arranged rectangular plate 14. Along one long side of the vertical plate 14 is attached to this one horizontal rectangular plate 15 welded, which also along a short side with the vertical Plate 13 is welded. An inverted L-shaped retainer 16 extends from that of the plate 13 furthest end of the horizontal plate 15 from upwards. Between the holding piece 16 and the vertical plate 13 is a rigid one

arranged horizontal rod 17 of square cross-section.

The holding member 16 supports a stationary clamping device 18, the details of F g i. 3 can be seen. This stationary clamping device comprises a stationary jaw 19 which is fastened to the horizontal leg of the holding piece 16. and a movable jaw 21 which cooperates with the fixed jaw and can be moved in a perpendicular direction towards and away from the fixed jaw 19 by rods 22 and 23; the rods 22 and 23 slide in holes of fastened to the holding piece 16 bearing supports 24 and 25. The rods are below these bearing blocks interconnected by a cross piece 26, and the rods 22 and 23 are provided between the crosspiece 26 and the underside of the bearing pads 24 and 25 compression springs 27 and 28 pushed on in order to bias the cross piece downwards, so that the movable jaw 21 is also biased downwards against the fixed jaw 19.

A movable clamping device 29, which is generally the stationary clamping device. 18 is arranged so that it can be moved back and forth on the horizontal rod 17 between the stationary clamping device and the press. The movable clamping device comprises a two-part slide 31, the two halves of which are connected to one another by screws; this SchUtten can be displaced on the horizontal rod 17 . A fixed jaw 32 is attached to the top of the carriage part 31 , and a movable jaw 33 is provided which cooperates with the fixed jaw 32 ; the movable jaw 33 can be moved in a vertical direction towards and away from the fixed jaw by means of rods 34 and 35; in this case, the rods 34 and 35 slide in holes of bearing blocks 36 and 37, which are made of one piece with the lower part of the carriage 31. The rods 34 and 35 are connected to one another by a crosspiece 38 below the bearing blocks. Compression springs 41 and 42 are pushed onto the rods between the bearing blocks 36 and 37 on the one hand and the movable jaw 33 on the other hand in order to pretension the movable jaw upward relative to the fixed jaw.

The vertical plate 14 carries according to FIG. 1 an electric motor 43 which, while reducing its speed, drives a vertical drive shaft 45 via a drive belt 44 which extends upwards through a bearing 46 fastened to the plate 15 . At the upper end of the vertical drive shaft 45 , an assembly 47 is attached, which forms a crank with a variable crank radius. According to FIG. 5 a rectangular block 48 attached to the upper end of the drive shaft 45 , which has a groove 49 on its upper side, in which a slide 51 is displaceable, which can be adjusted with the aid of a screw 52 and fixed in the desired position. The carriage 51 carries a crank pin 53, the axis of which is perpendicular. When the screw 52 is turned, the horizontal distance between the axis of the drive shaft 45 and the axis of the crank pin 53 is changed, that is, the stroke of the crank can be varied.

The slide 31 of the movable clamping device carries on its underside a downwardly projecting bolt 54, and on this bolt it is

one end of a connecting rod 55 is mounted, which is mounted with its other end on the crank pin 53 . When the drive shaft 45 is rotated, the movable clamping device 29 is thus moved to and fro with respect to the stationary clamping device 18 , and the stroke length of this movement can be varied by adjusting the stroke of the crank.

A slot 56 extends through the connecting rod or connecting rod, in which a generally horizontal lever 57 is arranged, which is rotatably mounted on a horizontal pin 58 extending transversely to the slot. From one end of the lever 57 of a bolt 59 extends, a roller is rotatably mounted on the 61 "5, which is received by an opening 62 which extends at one end of the slot 56 through the connecting rod. The roller 61 forms a movement pick-up element which engages the profiled upper side of a cam disk 63 which is attached to the crank pin 53 below the connecting rod. The crank pin is in turn firmly connected to the slide 51 . The other end of the lever 57 is shown in FIG. 1 is angled downwards and the lower edge of the lever engages the upper end of a vertical screw 64 which extends upwards through a hole in the center of the crosspiece 38 of the movable clamping device. The screw 64 carries a nut 65, so that there is an adjustable connection between the screw and the crosspiece The profiled top of the cam plate 63 is divided into two zones 66 and 67 , the zone 66 is lower than the zone 67 and both zones are connected by inclined sections 68 and 69 with each other During part of each revolution of the drive shaft 45 , the roller 61 engages the higher zone 67 of the cam disc so that the roller moves upward and the other end of the lever 57 is pivoted downward, as a result, the crosspiece 38 and 38 together with this, the movable jaw 33 of the movable clamping device is moved downwards towards the fixed jaw 32 in order to close the movable clamping device conclude. During the remainder of each revolution of the drive shaft, the roller 61 engages the lower-lying zone 66 of the cam disk 63 , so that the movable clamping device is opened.

The drive shaft 45 carries a cam disk 71 which is similar to the cam disk 63 described and the underside of which is divided into two zones 72 and 73 , on which a movement pickup element in the form of a roller 74 engages; the roller 74 is mounted on a pin 75 at one end of a generally horizontal lever 76 which in turn is mounted on a horizontal pin 77 ; the bolt 77 is built into a component 78 projecting with respect to the holding piece 16 . The other end of the lever 76 engages at the lower end of a according to FIG. 3 screw 79 built into the crosspiece 26 of the stationary clamping device. The screw 79 carries a lock nut 81. As with the movable clamping device, the stationary clamping device is closed during part of each revolution of the drive shaft and opened with the aid of the cam disk 71 during the remaining part of each revolution.

A further cam disk 82 is attached to the drive shaft 45 , the peripheral surface of which forms a cam track; the cam disk 82 can be seen from FIGS. On the cam surface of the cam disk 82 engages a roller 83 on which; one end of a lever 84 is supported; the lever 84 is mounted on a pin 85 projecting upward from the horizontal plate 15 . At the other end of the lever 84, the rope 86 is fastened a Bowden cable 80, whose other end is connected to the ι control device of the press.

As already mentioned, the press is provided with a guide pin 11 which is rounded at the lower end and which enters a hole that was punched into the strip during a previous operation in order to determine the position of the strip during the next punching operation. So that the strip can be moved through this pin 11 , the strip must be released; this is done with the aid of a switch-off device which renders the control of the stationary clamping device by the cam disk 71 ineffective. The disconnection device comprises an extension 87 of the ram 6, which is arranged so that it engages one end of a lever 88 a, which is rotatably mounted on a bracket 89 attached to the vertical plate 13. The other end of the lever 88 is connected by a vertical rod 90 to an arm 91 which is fastened to one end of a horizontal shaft 92 , whose position in bearings in the plate 13 or in the holding piece 16 by collars or adjusting rings 93 and 94 is determined. At the end of the shaft 92 facing away from the arm 91, a second arm 95 is attached to this shaft, the free end of which is below; the end of the lever 76 is directly below the screw 79 , which is built into the crosspiece 26 of the stationary clamping device.

The operation of the feeding device will now be described. When the device is to be used, the free end of a strip of material 7 withdrawn from a spool or roll is passed between the jaws 19 and 21 of the stationary clamping device 18 and between the jaws 32 and 33 of the movable clamping device 29 , so that the Strip below the punches 8 and 9 extends over the table of the press. The working cycle for one complete revolution of the drive shaft 45 is described below; this working cycle; starts at about 5 ° before the movable clamping device reaches its bottom dead center. During the 5 ° rotation before the movable clamp reaches its bottom dead center, the cam 63 attached to the crank pin 53 causes the movable clamp to close to clamp the strip, the strip being held flat. During this period of time, the movable clamping device performs only a very small linear movement, since this clamping device is located near the end of its stroke. At this point in time, the stationary clamping device is closed because it is at its bottom dead center, so that the strip is held in place by both the movable and the stationary clamping device. During the rotation by 5 ° after reaching the bottom dead center position

the roller 74 moves to the zone 73 of the cam plate 71 so that the stationary clamping device is opened. When the drive shaft continues to rotate, the movable clamping device is accelerated away from the stationary clamping device, reaching its highest speed at a distance of 90 ° from the bottom dead center, whereupon the movement is slowed down. During this movement the one is movable

ο clamping device closed, so that the strip moves together with this clamping device and is advanced relative to the press by an amount equal to the stroke of the crank. During the rotation by the last 5 ° before top dead center, ie when the movable clamping device moves extremely slowly, the roller 74 passes from the zone 73 of the cam disk 71 to the zone 72 , and the stationary clamping device is closed so that it engages the strip and exerts a braking effect on the strip. In the top dead center, the strip is thus clamped both by the stationary and by the movable clamping device.

During the rotation by 5 ° after top dead center, the roller 61 passes from the zone 67 of the cam disk 63 to the zone 66 , so that the movable clamping device is opened. During the further rotation of 170 °, the movable clamping device returns to its bottom dead center position, but since it is open the strip is not moved. As a result of the mode of operation of the switch-off direction, the strip is kept at rest; this is brought about by the stationary clamping device which is now closed.

While the movable clamping device is accelerated towards the stationary clamping device, the roller 83 passes from one zone of the cam disk 82 to the other zone, and this has the effect that a signal is transmitted via the Bowden cable 80 to the control device of the press, to the Press to operate. The ram 6 is now moved downwards towards the strip 7 . Before the guide pin 11 reaches the strip 7 , the extension or arm 87 of the press ram 6 engages the lever 88 which moves the rod 90 upwards; this movement is transmitted to the free end of the arm 95 which, as shown in FIG. 3 moved in the direction of arrow 96 . Thus, the cross piece 26 of the stationary clamping device is moved upwards in order to open the stationary clamping device. At the same time, the end of the lever 76 is moved upward so that the roller 74 is lifted downwardly from the surface 72 of the cam disk 71 , as shown in FIG. 6 is indicated by the arrow 97. In this way the cam disk 71 is rendered ineffective and the strip 7 is released from the stationary clamping device at the moment in which the lower end of the guide pin 11 enters the hole previously punched in the strip 7. As soon as the ram 6 moves upwards again, the boom 87 releases the lever 88 so that the stationary clamping device closes again to clamp the strip, and the roller 74 again engages the zone 72 of the cam disk 71 .

At a distance of 5 ° before reaching the bottom dead center position, the roller 74 goes on the

Claims (4)

Zone 73 of the cam disk 71 over, so that the movable clamping device is opened; the working cycle described is then repeated. Claims: 5, 1. Device for the gradual feeding of strip or strand-shaped material with a gripper that can be moved back and forth by a crank mechanism with a clamping jaw, which is synchronized with the gripper movement via a cam rotating with the crank pin and a linkage that interacts with it is movable characterized in that 5 the axis of rotation (45) formed in per se known movement of the clamping jaw (33) in the direction of »of the crank mechanism (47) the cam surface (66 to 69) on an end face of the cam (63) and the linkage is a double lever (57 ) mounted on the connecting rod (55) with a pivot axis (58) running at right angles to the axis of rotation of the crank drive, one end of which cooperates with the cam surface and the other end of which is connected to the clamping jaw. 2. Apparatus according to claim 1, characterized in that the double lever (57) is arranged in a longitudinal slot (56) of the connecting rod (55) . 3. Apparatus according to claim 1 or 2, characterized in that at the end of the double lever (57) cooperating with the cam surface (66 to 69 ) a roller (61) resting on the cam surface is mounted, the bearing axis (59) in Extends the longitudinal direction of the double lever. 4. Apparatus according to claim 1 to 3 with a second stationary gripper with a clamping jaw which can be moved into the open or closed position via a second cam rotating with the axis of rotation of the crank drive and a second linkage cooperating with this, characterized in that also the clamping jaw (21) of the stationary gripper (18) can be moved in the direction of the axis of rotation (45) of the crank drive (47) and the cam surface (72, 73) is formed on an end face of the second cam (71) and the second linkage is a double lever ( 76) , one end of which cooperates with the cam surface of the second cam and the other end of which is connected to the clamping jaw of the stationary gripper. Considered publications:
German patent specifications No. 614 782, 704 387:
U.S. Patent No. 2,696,380. For this purpose 2 sheets of drawings 709 647/306 9.67 © ButuIesdruckerd Berlin «09 531/269