CN220297790U - Board clamping device of plastic uptake machine - Google Patents

Abstract

The application discloses plastic uptake machine's panel clamping device belongs to the field of panel centre gripping, and it is including placing the platform and placing in placing the panel body of platform top surface, and the both sides face of placing the platform all is fixed with two mounting panels, is provided with the cylinder on the mounting panel, and the top of cylinder piston rod is fixed with the grip block, and the bottom surface of grip block can with the top surface looks butt of panel body, is provided with the actuating mechanism who is used for driving the cylinder pivoted on placing the platform. The application has the effect of being convenient for with stable fixing of panel body on placing the bench.

Description

Board clamping device of plastic uptake machine

Technical Field

The application relates to the field of plate clamping, in particular to a plate clamping device of a plastic sucking machine.

Background

The plastic sucking machine is also called a thermoplastic forming machine, and is a machine for sucking thermoplastic plastic coiled materials such as PVC, PE, PP, PET, HIPS which are heated and plasticized into products such as advanced packaging boxes, frames and the like with various shapes. The plastic sucking machine heats plastic sheet or plate, and makes the plastic sheet or plate deform with mold, vacuum or pressure to reach required shape and size, and with the auxiliary steps, the plastic sucking machine has application. Clamping devices are generally arranged on the plastic suction machine, and plastic sheets or plates are fixed through the clamping devices during production.

The utility model discloses a board clamping device of plastic uptake machine as in chinese patent with publication No. CN208529703U, including the mounting panel, the panel body, the equal fixedly connected with connecting plate in upper end both sides of mounting panel, the panel body is located between two connecting plates, the equal fixedly connected with of upper end of two connecting plates carries out fixed fixture to the panel body, two fixture fix and spacing the both ends of panel body respectively, fixture includes the elastic mechanism of fixed connection in the connecting plate upper end, elastic mechanism's upper end one side fixedly connected with diaphragm, elastic mechanism includes two risers of fixed connection in the connecting plate upper end, the upper end lateral wall of two risers is equipped with two bar grooves, the equal fixedly connected with extension spring in the interior bottom of two bar grooves, the upper end fixedly connected with fixed plate of two extension springs, and the lateral wall fixedly connected with of fixed plate and diaphragm, the stopper that the one end fixedly connected with that the extension spring was kept away from to the diaphragm corresponds with panel body position, the lower extreme fixedly connected with of stopper carries out fixed fixture to the panel body, and the lower extreme of fixture can offset with the upper end of panel body.

In the above-mentioned related art, when needs are fixed to panel body, through upwards tensile diaphragm, the diaphragm passes through stopper drive grip block upward movement, then puts into the panel body between two connecting plates, then unclamps the diaphragm, and the diaphragm moves down under extension spring's effect, makes the bottom surface of grip block and the top surface looks butt of panel body to fix the panel body between two connecting plates, because extension spring has certain elasticity, thereby make the panel body fix the fixity between two connecting plates relatively poor.

Disclosure of Invention

In order to improve when fixing the panel, need the staff to upwards pull two diaphragms simultaneously, then place the panel body between two connecting plates again to be inconvenient for the staff to fix the problem of panel body, this application provides a plastic uptake machine's panel clamping device.

The application provides a panel clamping device of plastic uptake machine adopts following technical scheme:

including place the platform and place in place the panel body of platform top surface, the both sides face of placing the platform all is fixed with two mounting panels, be provided with the cylinder on the mounting panel, the top of cylinder piston rod is fixed with the grip block, the bottom surface of grip block can with the top surface looks butt of panel body, place and be provided with on the platform and be used for the drive cylinder pivoted actuating mechanism.

Through adopting above-mentioned technical scheme, when needs press from both sides tightly to panel, through placing panel on placing the platform, then through actuating mechanism drive cylinder rotation, make the piston rod of cylinder drive grip block rotate, make the grip block rotate to the panel body directly over, then start the cylinder, the piston rod of cylinder drives the grip block and moves down, makes the bottom surface of grip block and the top surface looks butt of panel body to with the stable fixed of panel body on placing the platform.

Preferably, the placing table comprises a placing plate, side plates are fixed on two sides of the bottom surface of the placing plate, the driving mechanism comprises two rotating shafts, the two rotating shafts are respectively and rotatably installed between the two side plates, two ends of each rotating shaft respectively penetrate through two side surfaces of the side plates, which are far away from each other, the top surface of the mounting plate is provided with a mounting hole, the air cylinder is inserted into the mounting hole, the air cylinder is rotatably connected with the mounting plate through the mounting hole, a bevel gear I is arranged on the air cylinder, a bevel gear II is respectively arranged at two ends of each rotating shaft, the bevel gear I is meshed with the bevel gear II, and a driving assembly for driving the rotating shafts to rotate is arranged on the placing table.

By adopting the technical scheme, the plate is placed on the placing table, the driving assembly drives the rotating shaft to rotate, the rotating shaft drives the bevel gear II to rotate, the bevel gear II drives the bevel gear I to rotate, the bevel gear drives the air cylinder to rotate, and the piston rod of the air cylinder drives the clamping plate to move to the upper part of the plate body, so that the air cylinder is convenient to start, the piston rod of the air cylinder drives the clamping plate to move downwards, the bottom surface of the clamping plate is abutted with the top surface of the plate body, and the plate body is clamped on the placing table; when the plate body needs to be taken down from the placing table, the air cylinder is started, the piston rod of the air cylinder drives the clamping plate to move upwards, so that the clamping plate is separated from the plate body, then the driving assembly drives the rotating shaft to rotate reversely, the rotating shaft drives the bevel gear II to rotate, the bevel gear II drives the bevel gear I to rotate, the bevel gear drives the air cylinder to rotate, the piston rod of the air cylinder drives the clamping plate to rotate, the clamping plate rotates to one side of the plate body, and the plate body is convenient to take down from the placing table.

Preferably, a supporting plate is fixed between the two side plates, the driving assembly comprises a motor arranged on the supporting plate, a first belt pulley is arranged on an output shaft of the motor, a second belt pulley is arranged on the two rotating shafts, and a driving belt is wound on the outer peripheral surface of the second belt pulley and the outer peripheral surface of the first belt pulley respectively.

Through adopting above-mentioned technical scheme, through the starter motor, the motor drives band pulley one and rotates, and band pulley one drives two drive belt and rotates, makes two drive belt pulley two rotations respectively to make two band pulleys two drive two axis of rotation rotations respectively.

Preferably, the through grooves are formed in two sides of the bottom surface of the placing plate, sleeves are arranged on two sides of the bottom surface of the placing plate and are communicated with the through grooves, ejector rods are inserted into the sleeves, the top ends of the ejector rods are inserted into the through grooves, the top surfaces of the ejector rods are coplanar with the top surfaces of the placing plate, the ejector rods are in threaded connection with the sleeves, the ejector rods are vertically connected with the placing plate in a sliding mode through the through grooves, and driving pieces used for driving the sleeves to rotate are arranged on the rotating shafts.

Through adopting above-mentioned technical scheme, when the axis of rotation rotates, the axis of rotation drives bevel gear two and rotates, and bevel gear two drives bevel gear one and rotates, and bevel gear one drives the cylinder and rotate, makes the piston rod of cylinder drive grip block rotate, makes the grip block rotate to one side of panel body, and driving piece drive sleeve rotates simultaneously, and sleeve drive ejector pin upwards moves, makes the ejector pin upwards jack-up with the panel body, makes the panel body break away from and places the platform to the staff of being convenient for takes off the panel body from placing the bench.

Preferably, the driving member includes a worm wheel disposed on the sleeve, and a screw tooth is disposed on an outer circumferential surface of the rotating shaft, and is engaged with the worm wheel.

Through adopting above-mentioned technical scheme, when the axis of rotation rotated, the axis of rotation drove helical tooth and rotated, helical tooth drive worm wheel rotation to make the worm wheel drive sleeve rotation.

Preferably, the ejector rod comprises a stud arranged in the sleeve, the stud is in threaded connection with the sleeve, a push rod is fixed on the top surface of the stud, the top end of the push rod is inserted into the through groove, and the outer side surface of the push rod is attached to the inner side surface of the through groove.

Through adopting above-mentioned technical scheme, when the sleeve rotates, sleeve drive double-screw bolt along vertical removal, and the double-screw bolt drives the push rod along vertical removal to reduce the double-screw bolt and follow sleeve pivoted possibility.

Preferably, the limiting blocks are fixed on two side surfaces of the push rod, the top surfaces of the limiting blocks are coplanar with the top surface of the push rod, limiting grooves are formed in the inner side surfaces of the through grooves, the limiting grooves penetrate through the top surface of the placing plate, and the limiting blocks can be embedded in the limiting grooves.

Through adopting above-mentioned technical scheme, when the sleeve rotates, sleeve drive double-screw bolt along the downward movement, and the screw rod drives the push rod and moves down, and the push rod drives stopper downward movement, makes the stopper remove to the spacing inslot to reduce the possibility that the push rod breaks away from logical groove.

Preferably, a rubber pad is fixed on the bottom surface of the clamping plate.

Through adopting above-mentioned technical scheme, through being fixed with the rubber pad in the bottom surface of grip block, when starting the cylinder, the piston rod of cylinder drives the grip block and moves down, makes the bottom surface of rubber pad and the top surface looks butt of panel body to when making the grip block carry out the centre gripping to panel body fixed, reduce the possibility that the indentation appears on the surface of panel body.

In summary, the present application includes at least one of the following beneficial technical effects:

1. when the plate needs to be clamped, the plate is placed on the placing table, the driving mechanism drives the air cylinder to rotate, the piston rod of the air cylinder drives the clamping plate to rotate, the clamping plate rotates to be right above the plate body, then the air cylinder is started, the piston rod of the air cylinder drives the clamping plate to move downwards, the bottom surface of the clamping plate is abutted with the top surface of the plate body, and therefore the plate body is stably fixed on the placing table;

2. placing the plate on a placing table, driving a rotating shaft to rotate through a driving assembly, driving a bevel gear II to rotate by the rotating shaft, driving a bevel gear I to rotate by the bevel gear II, driving a gas cylinder to rotate by the bevel gear II, and driving a clamping plate to move to the upper part of the plate body by a piston rod of the gas cylinder, so that the gas cylinder is convenient to start, the piston rod of the gas cylinder drives the clamping plate to move downwards, the bottom surface of the clamping plate is abutted with the top surface of the plate body, and the plate body is clamped on the placing table; when the plate body needs to be taken down from the placement table, the air cylinder is started, the piston rod of the air cylinder drives the clamping plate to move upwards, so that the clamping plate is separated from the plate body, then the driving assembly drives the rotating shaft to rotate reversely, the rotating shaft drives the bevel gear II to rotate, the bevel gear II drives the bevel gear I to rotate, the bevel gear drives the air cylinder to rotate, the piston rod of the air cylinder drives the clamping plate to rotate, and the clamping plate rotates to one side of the plate body, so that the plate body is convenient to take down from the placement table;

3. through the starter motor, the motor drives band pulley one and rotates, and band pulley one drives two drive belt and rotates, makes two drive belt drive two band pulleys two rotate respectively to make two band pulley two drive two axis of rotation rotations respectively.

Drawings

Fig. 1 is a schematic view of the overall structure of a sheet clamping device of a suction molding machine according to an embodiment of the present application.

Fig. 2 is a schematic structural view of a driving mechanism in an embodiment of the present application.

Fig. 3 is a cross-sectional view of a sleeve in an embodiment of the present application.

Reference numerals: 1. a placement table; 11. placing a plate; 12. a side plate; 13. a plate body; 2. a mounting plate; 21. a mounting hole; 22. a cylinder; 23. a clamping plate; 24. a rubber pad; 3. a driving mechanism; 31. a rotating shaft; 32. bevel gears I; 33. bevel gears II; 34. a motor; 35. a belt wheel I; 36. a belt wheel II; 37. a transmission belt; 38. a support plate; 4. a sleeve; 41. a through groove; 42. a push rod; 421. a stud; 422. a push rod; 43. a limiting block; 44. a limit groove; 45. a worm wheel; 46. helical teeth.

Detailed Description

The present application is described in further detail below in conjunction with figures 1-3.

The embodiment of the application discloses a plate clamping device of a plastic sucking machine.

Referring to fig. 1, a plate clamping device of a plastic sucking machine comprises a placing table 1 and a plate body 13 placed on the top surface of the placing table 1, wherein the placing table 1 comprises a placing plate 11 and side plates 12 fixed on two sides of the bottom surface of the placing plate 11, the side surfaces of the two side plates 12 away from each other are coplanar with the two side surfaces of the placing plate 11, and the plate body 13 is placed on the top surface of the placing plate 11.

Referring to fig. 1 and 2, two mounting plates 2 are fixed to both side surfaces of the placement plate 11, and the two mounting plates 2 are respectively located on both side surfaces of the placement plate 11. The top surface of mounting panel 2 has seted up mounting hole 21, and mounting hole 21 runs through mounting panel 2 along vertical, and mounting hole 21 interpolation is equipped with vertical cylinder 22 that is provided with, and cylinder 22 passes through mounting hole 21 and mounting panel 2 rotation and is connected. The top of the piston rod of the air cylinder 22 is fixed with a clamping plate 23, the bottom surface of the clamping plate 23 is fixed with a rubber pad 24, the bottom surface of the rubber pad 24 can be abutted with the top surface of the plate body 13, and the side plate 12 is provided with a driving mechanism 3 for driving the air cylinder 22 to rotate.

The staff places panel body 13 on placing plate 11, drives cylinder 22 through actuating mechanism 3 and rotates, and the piston rod of cylinder 22 drives grip block 23 rotation, makes grip block 23 remove to directly over panel body 13, then starts cylinder 22, and the piston rod of cylinder 22 moves down, and the piston rod of cylinder 22 drives grip block 23 and moves down, makes the bottom surface of rubber pad 24 and the top surface butt of panel body 13 to press from both sides panel body 13 on placing plate 11.

Referring to fig. 2, the driving mechanism 3 includes two rotation shafts 31 rotatably installed between the two side plates 12, and both ends of the rotation shafts 31 pass through sides of the two side plates 12 away from each other, respectively. The outer peripheral surface of the cylinder 22 is sleeved and fixed with a first bevel gear 32, two ends of the rotating shaft 31 are respectively sleeved and fixed with a second bevel gear 33, and the first bevel gear 32 is meshed with the second bevel gear 33. A supporting plate 38 is fixed between the two side plates 12, a motor 34 is fixed on the top surface of the supporting plate 38, a belt wheel I35 is sleeved and fixed on an output shaft of the motor 34, belt wheels II 36 are sleeved and fixed on the outer peripheral surfaces of the two rotating shafts 31, and a driving belt 37 is wound on the outer peripheral surfaces of the belt wheels I35 and the two belt wheels II 36 respectively.

The staff passes through the starter motor 34, and motor 34 drives band pulley one 35 and rotates, and band pulley one 35 drives two drive belt 37 respectively and rotates, and two drive belt 37 drive two band pulleys two 36 respectively rotate, makes two band pulleys two 36 drive two axis of rotation 31 respectively and rotates, and axis of rotation 31 drives bevel gear two 33 and rotates, and bevel gear two 33 drives bevel gear one 32 and rotate to make the cylinder 22 of placing the board 11 both sides simultaneously rotate, make the piston rod of cylinder 22 drive grip block 23 and rotate to directly over the panel body 13.

Referring to fig. 2 and 3, two through grooves 41 are respectively formed on two sides of the bottom surface of the placement plate 11, two sleeves 4 are respectively arranged on two sides of the bottom surface of the placement plate 11, the sleeves 4 are rotatably connected with the placement plate 11, and the sleeves 4 are communicated with the through grooves 41. The sleeve 4 is internally inserted with a push rod 42, the push rod 42 comprises a stud 421 inserted into the sleeve 4, and the stud 421 is in threaded connection with the sleeve 4. The top surface of double-screw bolt 421 is fixed with push rod 422, and in the through groove 41 was inserted at the top of push rod 422, the top surface of push rod 422 and the top surface of placing plate 11 are coplanar, and the lateral surface of push rod 422 is laminated with the medial surface of through groove 41 mutually, and push rod 422 passes through groove 41 along vertical and placing plate 11 sliding connection. Both side surfaces of the push rod 422 are integrally formed with a limiting block 43, and the top surface of the limiting block 43 is coplanar with the top surface of the push rod 422. Limiting grooves 44 are formed in the opposite inner side surfaces of the through grooves 41, the limiting grooves 44 penetrate through the top surface of the placing plate 11, and the limiting blocks 43 can be embedded in the limiting grooves 44.

Referring to fig. 2 and 3, two helical teeth 46 are provided on the outer circumferential surface of the rotary shaft 31, and the two helical teeth 46 are located on both sides of the pulley two 36, respectively. The outer circumferential surface of the sleeve 4 is sleeved and fixed with a worm gear 45, and the worm gear 45 is meshed with the spiral teeth 46.

When the rotation shaft 31 rotates, the rotation shaft 31 drives the bevel gear II 33 to rotate, the bevel gear II 33 drives the bevel gear I32 to rotate, the bevel gear drives the air cylinder 22 to rotate, the piston rod of the air cylinder 22 drives the clamping plate 23 to rotate to one side of the plate body 13, meanwhile, the rotation shaft 31 drives the spiral teeth 46 to rotate, the spiral teeth 46 drive the worm wheel 45 to rotate, the worm wheel 45 drives the sleeve 4 to rotate, the sleeve 4 drives the stud 421 to move upwards, the stud 421 drives the push rod 422 to move upwards, and when the clamping plate 23 rotates towards one side of the plate body 13, the push rod 422 simultaneously jacks up the plate body 13 upwards, so that the plate body 13 is separated from the placing plate 11, and the plate body 13 is convenient to take off the placing plate 11 by staff.

The implementation principle of the plate clamping device of the plastic sucking machine is as follows: when the plate body 13 needs to be clamped on the placing plate 11, the plate body 13 is placed on the top surface of the push rod 422, the motor 34 is started, the motor 34 drives the belt pulley I35 to rotate, the belt pulley I35 drives the transmission belt 37 to rotate, the transmission belt 37 drives the belt pulley II 36 to rotate, the belt pulley II 36 drives the rotating shaft 31 to rotate, the rotating shaft 31 drives the spiral teeth 46 to rotate, the spiral teeth 46 drive the worm wheel 45 to rotate, the worm wheel 45 drives the sleeve 4 to rotate, the sleeve 4 drives the stud 421 to move downwards, the stud 421 drives the push rod 422 to move downwards, the push rod 422 drives the plate body 13 to move downwards, and the top surface of the push rod 422 moves downwards to be coplanar with the top surface of the placing plate 11, so that the plate body 13 is placed on the placing plate 11. When the push rod 422 drives the plate body 13 to move downwards, the rotating shaft 31 also drives the bevel gear two 33 to rotate, the bevel gear two 33 drives the bevel gear one 32 to rotate, the bevel gear one 32 drives the air cylinder 22 to rotate, the piston rod of the air cylinder 22 drives the clamping plate 23 to rotate, and when the plate body 13 is placed on the placing plate 11, the clamping plate 23 also moves to the upper side of the plate body 13. Then, the air cylinder 22 is started, the piston rod of the air cylinder 22 moves downwards, the piston rod of the air cylinder 22 drives the clamping plate 23 to move downwards, the bottom surface of the rubber pad 24 is abutted against the top surface of the plate body 13, and therefore the plate body 13 is stably fixed on the placing plate 11.

When the plate body 13 needs to be removed from the placement plate 11, the piston rod of the air cylinder 22 moves upwards by starting the air cylinder 22, and the piston rod of the air cylinder 22 drives the clamping plate 23 to move upwards, so that the rubber pad 24 is separated from the plate body 13. Then, the motor 34 is started, the motor 34 drives the belt pulley one 35 to reversely rotate, the belt pulley one 35 drives the driving belt 37 to reversely rotate, the driving belt 37 drives the belt pulley two 36 to reversely rotate, the belt pulley two 36 drives the rotating shaft 31 to reversely rotate, the rotating shaft 31 drives the bevel gear two 33 to reversely rotate, the bevel gear two 33 drives the bevel gear one 32 to rotate, the bevel gear one 32 drives the air cylinder 22 to rotate, the piston rod of the air cylinder 22 drives the clamping plate 23 to rotate, and the clamping plate 23 rotates to one side of the plate body 13. When the air cylinder 22 rotates, the rotating shaft 31 simultaneously drives the spiral teeth 46 to rotate, so that the spiral teeth 46 drive the worm wheel 45 to rotate, the worm wheel 45 drives the sleeve 4 to rotate, the sleeve 4 drives the stud 421 to move upwards, the stud 421 drives the push rod 422 to move upwards, and when the clamping plate 23 rotates to one side of the plate body 13, the push rod 422 simultaneously lifts up the plate body 13, so that the plate body 13 is separated from the placing plate 11, and a worker can conveniently take down the plate body 13 from the placing plate 11.

The foregoing are all preferred embodiments of the present application, and are not intended to limit the scope of the present application in any way, therefore: all equivalent changes in structure, shape and principle of this application should be covered in the protection scope of this application.

Claims (8)

1. A board clamping device of a plastic sucking machine is characterized in that: including place platform (1) and place in panel body (13) of placing platform (1) top surface, the both sides face of placing platform (1) all is fixed with two mounting panel (2), be provided with cylinder (22) on mounting panel (2), the top of cylinder (22) piston rod is fixed with grip block (23), the bottom surface of grip block (23) can with the top surface looks butt of panel body (13), be provided with on placing platform (1) and be used for the drive actuating mechanism (3) of cylinder (22) pivoted.

2. A sheet clamping device for a vacuum forming machine as claimed in claim 1, wherein: place platform (1) including placing board (11), the bottom surface both sides of placing board (11) all are fixed with curb plate (12), actuating mechanism (3) are including two axis of rotation (31), two axis of rotation (31) rotate respectively and install in two between curb plate (12), two are passed respectively in the both ends of axis of rotation (31) curb plate (12) side that keep away from each other, mounting hole (21) have been seted up to the top surface of mounting panel (2), cylinder (22) are inserted and are located in mounting hole (21), cylinder (22) are passed through mounting hole (21) with mounting panel (2) swivelling joint, be provided with bevel gear one (32) on cylinder (22), the both ends of axis of rotation (31) are provided with bevel gear two (33) respectively, bevel gear one (32) with bevel gear two (33) mesh, be provided with on placing platform (1) and be used for the drive rotating drive assembly of axis of rotation (31).

3. A sheet clamping device for a vacuum forming machine according to claim 2, wherein: a supporting plate (38) is fixed between the two side plates (12), the driving assembly comprises a motor (34) arranged on the supporting plate (38), a belt wheel I (35) is arranged on an output shaft of the motor (34), belt wheels II (36) are arranged on the rotating shafts (31), and a transmission belt (37) is wound on the outer peripheral surfaces of the belt wheels II (36) and the outer peripheral surface of the belt wheel I (35).

4. A sheet clamping device for a vacuum forming machine according to claim 2, wherein: the utility model discloses a push rod device for placing board (11), including board (11) and sleeve (4), lead to groove (41) and all set up logical groove (41) in the bottom surface both sides of placing board (11), the bottom surface both sides of placing board (11) all are provided with sleeve (4), sleeve (4) with lead to groove (41) and be linked together, sleeve (4) interpolation is equipped with ejector pin (42), the top of ejector pin (42) is inserted and is located in leading to groove (41), the top surface of ejector pin (42) with the top surface coplanarity of placing board (11), ejector pin (42) with sleeve (4) threaded connection, ejector pin (42) are through leading to groove (41) along vertical with place board (11) sliding connection, be provided with on axis of rotation (31) and be used for the drive sleeve (4) pivoted driving piece.

5. A sheet clamping device for a vacuum forming machine as defined in claim 4 wherein: the driving piece comprises a worm wheel (45) arranged on the sleeve (4), spiral teeth (46) are formed in the outer circumferential surface of the rotating shaft (31), and the spiral teeth (46) are meshed with the worm wheel (45).

6. A sheet clamping device for a vacuum forming machine as defined in claim 4 wherein: the ejector rod (42) comprises a stud (421) arranged in the sleeve (4), the stud (421) is in threaded connection with the sleeve (4), a push rod (422) is fixed to the top surface of the stud (421), the top end of the push rod (422) is inserted into the through groove (41), and the outer side surface of the push rod (422) is attached to the inner side surface of the through groove (41).

7. A sheet clamping device for a vacuum forming machine as defined in claim 6 wherein: limiting blocks (43) are fixed on two side surfaces of the push rod (422), the top surfaces of the limiting blocks (43) are coplanar with the top surfaces of the push rod (422), limiting grooves (44) are formed in the inner side surfaces of the through grooves (41), the limiting grooves (44) penetrate through the top surfaces of the placing plates (11), and the limiting blocks (43) can be embedded in the limiting grooves (44).

8. A sheet clamping device for a vacuum forming machine as claimed in claim 1, wherein: a rubber pad (24) is fixed on the bottom surface of the clamping plate (23).