Pull-up type quick broaching machine

Abstract

The utility model discloses a pull-up type quick broaching machine, which belongs to the technical field of broaching machines, and is characterized by comprising a base, an upright post arranged on the base, a griffe mechanism and a driving mechanism arranged on the upright post, a sliding table arranged on the upright post in a sliding manner, and the driving mechanism used for driving the sliding table to slide, a lower chuck used for clamping a broach is arranged on the base and located below the sliding table, the broach lifting mechanism is used for conveying the broach to the lower chuck or taking the broach away from the lower chuck, a containing base used for containing a workpiece to be machined is arranged on the sliding table in a sliding mode, and a tool plate used for supporting the workpiece is arranged on the sliding table. A clamping mechanism used for clamping a workpiece is arranged on the sliding table in a sliding mode, the clamping mechanism can bring the to-be-machined workpiece on the containing base to the tool plate or bring the machined workpiece away from the tool plate, the machining procedure of the broaching machine is reasonable, an operator conducts feeding and discharging at the lowest point of the stroke of the sliding table, the working intensity of workers can be reduced, and the machining efficiency is improved. The production efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of broaching machine, especially relates to an upper pull type quick broaching machine. BACKGROUND

[0002] The broaching machine is the machine tool that uses broach to process the through hole, plane and forming surface of workpiece.

[0003] The Chinese patent with the publication number CN201760660U discloses a screw rod vertical inner broaching machine, which comprises a machine bed, a workbench, a broach, a lower broach body and a broach lifting device arranged in the machine bed, the lower broach body and the broach lifting device are arranged at the position right below and the position right above the workbench respectively, the workbench is provided with a workpiece fixing device, at least one screw rod and at least one guide rod are arranged vertically in the machine bed, the screw rod and the guide rod are installed in cooperation with the workbench, so that the workbench moves up and down along the guide rod under the driving of the screw rod.

[0004] The above technical scheme has at least the following defects: the broaching machine needs workers to take down the workpiece first after the broaching is completed, and then the return process is carried out to prepare for the next broaching operation, but since the workbench is just at the highest point of its stroke when the workpiece is broached, it is extremely inconvenient for the workers to take the material at this position, and after the return process is completed, the workbench moves to the lowest point of its stroke, at which time the workers need to carry out the feeding of new workpieces at this position, which means that the workers need to frequently switch between different height levels when carrying out the feeding and discharging operations, which not only increases the working strength of the workers, but also reduces the overall production efficiency, and more importantly, the current operation process needs to complete the discharging operation first, and then the broaching machine can enter the return process, which is easy to cause misoperation and has safety hazards. UTILITY MODEL CONTENTS

[0005] The utility model aims at the above problems existing in the prior art, and provides an upper pull type quick broaching machine, and the technical problem to be solved by the utility model is how to make the processing procedure reasonable, reduce the working strength of workers and improve the overall production efficiency.

[0006] The above technical purposes of the utility model can be realized by the following technical solutions: a pull-up type rapid broaching machine, comprising a base, a stand column is arranged on the base, a broach lifting mechanism and a driving mechanism are arranged on the stand column, a sliding table is slidably arranged on the stand column, the driving mechanism is used for driving the sliding table to slide, a lower chuck for clamping a broach is arranged on the base, and the lower chuck is located below the sliding table, the broach lifting mechanism is used for conveying the broach to the lower chuck or taking the broach away from the lower chuck, a placing seat for placing a workpiece to be machined is arranged on the sliding table, a tool plate for supporting the workpiece is arranged on the sliding table, a clamping mechanism for clamping the workpiece is slidably arranged on the sliding table, and the clamping mechanism can take the workpiece to be machined on the placing seat to the tool plate or take the machined workpiece away from the tool plate.

[0007] In the pull-up type rapid broaching machine, the driving mechanism comprises a rotary driving source, a screw rod, a nut seat, a sliding rail one and a sliding block one, the rotary driving source is installed on the stand column, an output end of the rotary driving source is connected with the screw rod, the nut seat is threadedly connected with the screw rod and connected with the sliding table, the sliding rail one is arranged on the stand column, and the sliding block one is slidably arranged on the sliding rail one and connected with the sliding table.

[0008] In the pull-up type rapid broaching machine, the broach lifting mechanism comprises a rotary driving piece, a transmission shaft, a gear, a rack, a sliding rail two, a sliding block two, a broach lifting seat and an upper chuck, the rotary driving piece is installed on the broach lifting seat, the transmission shaft is rotationally arranged on the broach lifting seat, the rotary driving piece is used for driving the transmission shaft to rotate, the gear is coaxially arranged on the transmission shaft, the rack and the sliding rail two are arranged on the stand column, the gear is engaged with the rack, the sliding block two is slidably arranged on the sliding rail two and connected with the broach lifting seat, and the upper chuck is installed on the broach lifting seat and used for clamping the broach.

[0009] In the pull-up type rapid broaching machine, the clamping mechanism comprises a double-head air cylinder, at least two clamping jaws and at least two clamping jaw blocks, an output end of the double-head air cylinder is connected with the clamping jaws, the clamping jaw blocks are installed on the corresponding clamping jaws, and the double-head air cylinder is used for driving the two clamping jaws to approach or move away from each other, so that the two clamping jaw blocks approach or move away from each other.

[0010] In the pull-up type rapid broaching machine, the clamping mechanism is driven by a driving piece one to reciprocate between the placing seat and the tool plate.

[0011] In the pull-up type rapid broaching machine, the clamping mechanism is driven by a driving piece two to approach or move away from the tool plate along the length direction of the broach.

[0012] In the pull-up type rapid broaching machine, the first driving member is installed on the slide table, the second driving member is installed on the mounting plate, the output end of the first driving member is connected with the mounting plate through the connecting plate, and the output end of the second driving member is connected with the clamping mechanism.

[0013] In the pull-up type rapid broaching machine, the placing seat is driven to move by the third driving member, so that the placing seat and the workpiece to be processed avoid the clamping mechanism.

[0014] In the pull-up type rapid broaching machine, the slide table is provided with a supporting seat, a supporting base plate is slidably arranged on the supporting seat, the output end of the third driving member is fixed on the supporting seat, the third driving member is connected with the supporting base plate, and the placing seat is installed on the supporting base plate.

[0015] In the pull-up type rapid broaching machine, the slide table is provided with an avoiding hole one for avoiding the broach, and the tool plate is provided with an avoiding hole two for avoiding the broach.

[0016] Compared with the prior art, the pull-up type rapid broaching machine has the beneficial effects that:

[0017] The operator places the workpiece to be processed on the placing seat, the clamping mechanism clamps the workpiece to be processed on the placing seat to the tool plate, the broach mechanism transports the broach to the lower chuck, then the driving mechanism drives the slide table to slide upward, the slide table drives the clamping mechanism and the workpiece to be processed to move upward, the broach completes the processing of the workpiece to be processed, then the clamping mechanism drives the processed workpiece to move away from the tool plate, the driving mechanism drives the slide table to move downward to reset to the initial height, then the broach mechanism takes away the broach from the lower chuck, the slide table drives the clamping mechanism and the processed workpiece to move, the whole processing procedure is rationalized, the operator can perform feeding and discharging at the lowest point of the slide table, the working intensity of the operator can be effectively reduced, and the overall production efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is an external structure schematic view of the embodiment;

[0019] Figure 2 It is an internal structure schematic view of the embodiment;

[0020] Figure 3 It is a partial structure schematic view of the embodiment;

[0021] Figure 4 It is another partial structure schematic view of the embodiment;

[0022] Figure 5 It is an A part enlarged view of Figure 4 ​

[0023] Figure 6 Structure diagram of the embodiment slide table;

[0024] Figure 7 Structure diagram of the embodiment tool plate.

[0025] Reference signs: 1, base; 2, stand; 3, placing seat; 4, tool plate; 41, avoiding hole two; 5, broach lifting mechanism; 51, rotary driving part; 511, driving motor; 512, speed reducer; 52, transmission shaft; 53, gear; 54, rack; 55, slide rail two; 56, sliding block two; 57, broach lifting seat; 58, upper chuck; 6, driving mechanism; 61, rotary driving source; 62, screw rod; 63, nut seat; 64, slide rail one; 65, sliding block one; 7, clamping mechanism; 71, double-head air cylinder; 72, clamping jaw; 73, clamping jaw block; 8, driving part one; 81, connecting plate; 9, driving part two; 91, mounting plate; 92, connecting seat; 10, driving part three; 101, support seat; 102, support backing plate; 11, slide table; 111, avoiding hole one; 12, lower chuck; 13, workpiece. DETAILED DESCRIPTION

[0026] The following is a specific embodiment of the present application and further describes the technical solution of the present application in combination with the drawings, but the present application is not limited to these embodiments.

[0027] A pull-up type rapid broaching machine, as shown in Figures 1 to 7 The base 1 is provided with a stand 2, and the base 1 is provided with a lower chuck 12 for clamping the lower end of the broach.

[0028] The slide table 11 is slidably arranged on the stand 2, the tool plate 4 for supporting the workpiece 13 is arranged on the slide table 11, the lower chuck 12 is located below the slide table 11, further, the avoiding hole one 111 for avoiding the broach is arranged on the slide table 11, the avoiding hole two 41 for avoiding the broach is arranged on the tool plate 4, in this embodiment, the avoiding hole one 111 and the avoiding hole two 41 are coaxially arranged, the lower end of the broach can be clamped by the lower chuck 12 by passing through the avoiding hole two 41 and the avoiding hole one 111 in turn.

[0029] The driving mechanism 6 is arranged on the stand 2, the driving mechanism 6 is used for driving the slide table 11 to slide, that is, the driving mechanism 6 drives the slide table 11 to move up and down along the height direction of the stand 2.

[0030] Specifically, the driving mechanism 6 comprises a rotary driving source 61, a screw rod 62, a nut seat 63, a sliding rail one 64 and a sliding block one 65. The rotary driving source 61 is installed on the column 2. The rotary driving source 61 is preferably an electric motor. Alternatively, other driving sources with rotary function can also be used. The output end of the rotary driving source 61 is connected with the screw rod 62. The nut seat 63 is threadedly connected with the screw rod 62 and connected with the sliding table 11. The sliding rail one 64 is arranged on the column 2. The sliding block one 65 is slidingly arranged on the sliding rail one 64 and connected with the sliding table 11. The screw rod 62 and the sliding rail one 64 are arranged along the height direction of the column 2.

[0031] The screw rod 62 is driven to rotate by the rotary driving source 61. The nut seat 63 moves along the length direction of the screw rod 62. The sliding table 11 and the sliding block one 65 slide along the length direction of the sliding rail one 64.

[0032] The column 2 is provided with a broach lifting mechanism 5. The broach lifting mechanism 5 is used to transport the broach to the lower chuck 12 and can take the broach away from the lower chuck 12.

[0033] Specifically, the broach lifting mechanism 5 comprises a rotary driving part 51, a transmission shaft 52, a gear 53, a rack 54, a sliding rail two 55, a sliding block two 56, a broach seat 57 and an upper chuck 58. The rotary driving part 51 is installed on the broach seat 57. The transmission shaft 52 is rotationally arranged on the broach seat 57. The rotary driving part 51 is used to drive the transmission shaft 52 to rotate. In this embodiment, the rotary driving part 51 comprises a driving motor 511 and a speed reducer 512. The output end of the driving motor 511 is connected with the input end of the speed reducer 512. The output end of the speed reducer 512 is connected with the transmission shaft 52. The gear 53 is coaxially arranged on the transmission shaft 52. The rack 54 and the sliding rail two 55 are arranged on the column 2 and arranged along the height direction of the column 2. The gear 53 is engaged with the rack 54. The sliding block two 56 is slidingly arranged on the sliding rail two 55 and connected with the broach seat 57. The upper chuck 58 is installed on the broach seat 57. The upper chuck 58 is used to clamp the broach.

[0034] It should be noted that the lower chuck 12 and the upper chuck 58 belong to the prior art. In the field of broaching machines, the specific structure of the upper chuck 58 and how to clamp the broach will not be described here.

[0035] The transmission shaft 52 is driven to rotate by the rotary driving part 51. The transmission shaft 52 drives the gear 53 to rotate. The gear 53 rolls along the length direction of the rack 54. Thus, the broach seat 57 and the sliding block two 56 slide along the length direction of the sliding rail two 55. The upper chuck 58 moves along the vertical direction with the broach seat 57.

[0036] The sliding of the holder 57 is realized by the cooperation of the driving motor 511, the speed reducer 512, the transmission shaft 52, the gear 53 and the rack 54. Compared with the prior art, the structure is more compact, the space occupation is reduced, the requirement for vertical space is lower, and the application range is wider.

[0037] In the embodiment, the rack 54 is spaced apart and has two roots, the gear 53 has two roots corresponding to the two racks 54 respectively, the slide rail two 55 is spaced apart and has two roots, and the slide block two 56 has at least two roots corresponding to the two slide rails two 55 respectively, so as to ensure the stability and balance of the holder 57 during sliding, and avoid side warping.

[0038] The placing seat 3 for placing the workpiece 13 to be machined is slidably arranged on the sliding table 11, the placing seat 3 is adapted to the workpiece 13, so as to ensure the stability of the workpiece 13. The clamping mechanism 7 for clamping the workpiece 13 is slidably arranged on the sliding table 11, and the clamping mechanism 7 can take the workpiece 13 to be machined on the placing seat 3 to the tooling plate 4 or take the workpiece 13 machined to the tooling plate 4.

[0039] Specifically, the clamping mechanism 7 includes a double-head cylinder 71, at least two clamping jaws 72 and at least two clamping jaw blocks 73. The output end of the double-head cylinder 71 is connected with the clamping jaw 72, and the clamping jaw block 73 is installed on the corresponding clamping jaw 72. The double-head cylinder 71 is used to drive the two clamping jaws 72 to approach or move away from each other, so as to make the two clamping jaw blocks 73 approach or move away from each other.

[0040] The double-head cylinder 71 drives the two clamping jaws 72 to approach each other, and the two clamping jaws 72 drive the two clamping jaw blocks 73 to approach each other, so that the two clamping jaw blocks 73 cooperate to clamp the workpiece 13. Conversely, the double-head cylinder 71 drives the two clamping jaws 72 to move away from each other, and the two clamping jaws 72 drive the two clamping jaw blocks 73 to move away from each other, so as to release the workpiece 13.

[0041] The clamping mechanism 7 is driven by the driving part one 8 to reciprocate between the placing seat 3 and the tooling plate 4. The clamping mechanism 7 is driven by the driving part two 9 to approach or move away from the tooling plate 4 along the length direction of the broach. In the embodiment, the driving part one 8 and the driving part two 9 are both gas cylinders. The driving part one 8 is driven in the longitudinal direction, and the driving part two 9 is driven in the vertical direction. As other solutions, the driving part one 8 and the driving part two 9 can also be oil cylinders or electric cylinders.

[0042] Specifically, the first driving member 8 is installed on one side of the sliding table 11, the second driving member 9 is installed on the mounting plate 91, the mounting plate 91 is slidably arranged on the sliding table 11 through the sliding block cooperating with the slide rail on one side of the sliding table 11, the output end of the first driving member 8 is connected with the mounting plate 91 through the connecting plate 81, and the double-head cylinder 71 of the clamping mechanism 7 is installed on the connecting seat 92, and the output end of the second driving member 9 is connected with the connecting seat 92.

[0043] The connecting plate 81, the mounting plate 91, the second driving member 9, the connecting seat 92 and the clamping mechanism 7 are driven to move longitudinally by the first driving member 8, so that the clamping mechanism 7 can reciprocate between the placing seat 3 and the tool plate 4, and the connecting seat 92 and the clamping mechanism 7 are driven to move vertically by the second driving member 9, so that the clamping mechanism 7 can move close to or away from the tool plate 4 along the length direction of the broach.

[0044] It should be noted that in the embodiment, after the machining is completed, the clamping mechanism 7 drives the machined workpiece 13 to move upward along the length direction of the broach under the driving action of the second driving member 9, and then the clamping mechanism 7 moves away from the tool plate 4 under the driving action of the first driving member 8, so that the broach does not contact the machined workpiece 13 again when the broach is taken away from the lower clamp 12 by the broach taking mechanism 5.

[0045] The placing seat 3 is driven to move by the third driving member 10, so that the placing seat 3 and the workpiece 13 to be machined avoid the clamping mechanism 7.

[0046] Specifically, the sliding table 11 is provided with a support seat 101, and the support pad 102 is slidably arranged on the support seat 101. In the embodiment, the support pad 102 is slidably arranged on the support pad 102 through the sliding block cooperating with the slide rail on the support pad 102. The third driving member 10 is preferably a cylinder. The third driving member 10 is driven in the transverse direction. As other solutions, the third driving member 10 can also adopt an oil cylinder or an electric cylinder. The output end of the third driving member 10 is fixed on the support seat 101, the third driving member 10 is connected with the support pad 102, that is, the cylinder body is connected with the support pad 102, and the placing seat 3 is installed on the support pad 102.

[0047] It needs to be explained that, in the embodiment, in order to avoid the contact between the broach and the machined workpiece 13 when the broach mechanism 5 takes away the broach from the lower chuck 12, the clamping mechanism 7 and the machined workpiece 13 are moved under the driving of the driving part one 8 and the driving part two 9, and the positions of the two are above the placement seat 3. Then, the driving mechanism 6 drives the slide table 11 to move downward to the initial height, and the slide table 11 drives the clamping mechanism 7 and the machined workpiece 13 to move downward. In order to avoid the interference between the clamping mechanism 7 and the machined workpiece 13 and the placement seat 3 and the workpiece to be machined on the placement seat 3, the driving part three 10 drives the support pad plate 102 to slide, and the support pad plate 102 drives the placement seat 3 and the workpiece to be machined to move, so as to avoid the clamping mechanism 7 and the machined workpiece 13.

[0048] The working principle of the utility model is as follows:

[0049] Firstly, the operator places the workpiece to be machined 13 on the placement seat 3. The clamping mechanism 7 clamps the workpiece to be machined 13 on the placement seat 3. The driving part two 9 drives the clamping mechanism 7 to move upward, so that the workpiece to be machined 13 is separated from the placement seat 3. The driving part one 8 drives the clamping mechanism 7 to move close to the tool plate 4. The driving part two 9 drives the clamping mechanism 7 to move downward, until the lower end of the workpiece to be machined 13 abuts against the tool plate 4. The rotating driving part 51 drives the transmission shaft 52 to rotate. The transmission shaft 52 drives the gear 53 to rotate. The gear 53 rolls along the length direction of the rack 54. The broach seat 57 and the sliding block two 56 slide downward along the length direction of the slide rail two 55. The upper chuck 58 drives the broach to move downward along with the broach seat 57. The lower end of the broach passes through the avoiding hole two 41 and the avoiding hole one 111 in sequence and is clamped by the lower chuck 12. Then, the rotating driving source 61 drives the screw rod 62 to rotate. The nut seat 63 moves along the length direction of the screw rod 62. The slide table 11 and the sliding block one 65 slide along the length direction of the slide rail one 64. The slide table 11 drives the clamping mechanism 7 and the workpiece to be machined 13 to move upward. The broach machines the workpiece to be machined 13. After the machining is completed, the clamping mechanism 7 drives the machined workpiece 13 to move upward along the length direction of the broach under the driving of the driving part two 9. Then, the clamping mechanism 7 moves away from the tool plate 4 under the driving of the driving part one 8. The slide table 11 drives the clamping mechanism 7 and the workpiece to be machined 13 to move downward. The slide table 11 drives the clamping mechanism 7 and the machined workpiece 13 to move downward, until the slide table 11 moves downward to the initial height. At the same time, the driving part three 10 drives the placement seat 3 and the workpiece to be machined 13 to move, so as to avoid the clamping mechanism 7 and the machined workpiece 13. Moreover, the lower chuck 12 releases the broach. The upper chuck 58 clamps the broach to move upward along with the broach seat 57.

[0050] It should be noted that the processing procedure of the broaching machine is reasonable, the operator can perform feeding and discharging at the lowest point of the stroke of the slide table 11, so as to effectively reduce the working strength of the operator and improve the overall production efficiency.

[0051] It should be further explained that the clamping mechanism 7 clamps the workpiece 13 and the tool plate 4 simultaneously supports the workpiece 13 during the processing of the broach, so as to effectively improve the stability of the workpiece 13 and further improve the processing precision.

[0052] The specific embodiments described herein are merely illustrative of the spirit of the present application; those skilled in the art to which the present application belongs can make various modifications or supplements to the described specific embodiments or replace them with similar ways, but will not deviate from the spirit of the present application or exceed the scope defined by the appended claims.

Claims

1. A pull-up type quick draw bench comprising a base (1) on which a stand (2) is provided, characterized in that: The column (2) is provided with a broach mechanism (5) and a driving mechanism (6), the column (2) is slidably provided with a sliding table (11), the driving mechanism (6) is used for driving the sliding table (11) to slide, the base (1) is provided with a lower chuck (12) used for clamping a broach, and the lower chuck (12) is located below the sliding table (11), the broach mechanism (5) is used for conveying the broach to the lower chuck (12) or taking the broach away from the lower chuck (12), the sliding table (11) is slidably provided with a placing seat (3) used for placing a workpiece to be processed, the sliding table (11) is provided with a tool plate (4) used for supporting the workpiece, and the sliding table (11) is slidably provided with a clamping mechanism (7) used for clamping the workpiece, and the clamping mechanism (7) can take the workpiece to be processed on the placing seat (3) to the tool plate (4) or take the workpiece processed away from the tool plate (4).

2. A pull-up type quick draw bench according to claim 1, wherein: The driving mechanism (6) comprises a rotary driving source (61), a lead screw (62), a nut seat (63), a sliding rail one (64) and a sliding block one (65), the rotary driving source (61) is installed on the column (2), the output end of the rotary driving source (61) is connected with the lead screw (62), the nut seat (63) is threadedly connected on the lead screw (62) and connected with the sliding table (11), the sliding rail one (64) is arranged on the column (2), and the sliding block one (65) is slidably arranged on the sliding rail one (64) and connected with the sliding table (11).

3. The pull-up type quick draw bench according to claim 1, wherein: The broach mechanism (5) comprises a rotary driving piece (51), a transmission shaft (52), a gear (53), a rack (54), a sliding rail two (55), a sliding block two (56), a broach seat (57) and an upper chuck (58), the rotary driving piece (51) is installed on the broach seat (57), the transmission shaft (52) is rotationally arranged on the broach seat (57), the rotary driving piece (51) is used for driving the transmission shaft (52) to rotate, the gear (53) is coaxially arranged on the transmission shaft (52), the rack (54) and the sliding rail two (55) are arranged on the column (2), the gear (53) is engaged with the rack (54), the sliding block two (56) is slidably arranged on the sliding rail two (55) and connected with the broach seat (57), and the upper chuck (58) is installed on the broach seat (57) and used for clamping a broach.

4. The puller as set forth in claim 1, wherein: The clamping mechanism (7) comprises a double-head air cylinder (71), at least two clamping jaws (72) and at least two clamping jaw blocks (73), the output end of the double-head air cylinder (71) is connected with the clamping jaw (72), the clamping jaw block (73) is installed on the corresponding clamping jaw (72), and the double-head air cylinder (71) is used for driving two clamping jaws (72) to approach or move away from each other, so that two clamping jaw blocks (73) approach or move away from each other.

5. The puller as set forth in claim 1, wherein: The clamping mechanism (7) is driven by driving member one (8) to move reciprocally between the placement seat (3) and the tool plate (4).

6. A pull-up type quick draw bench according to claim 5, wherein: The clamping mechanism (7) is driven by driving member two (9) to move towards or away from the tool plate (4) along the length direction of the broach.

7. A pull-up type quick draw bench according to claim 6, wherein: The driving member one (8) is installed on the sliding table (11), the driving member two (9) is installed on the mounting plate (91), the output end of the driving member one (8) is connected with the mounting plate (91) through the connecting plate (81), and the output end of the driving member two (9) is connected with the clamping mechanism (7).

8. A pull-up type quick draw bench according to any one of claims 1 to 7, wherein: The placement seat (3) is driven by driving member three (10) to move, so that the placement seat (3) and the workpiece to be processed avoid the clamping mechanism (7).

9. A pull-up type quick draw bench according to claim 8, wherein: The sliding table (11) is provided with a support seat (101), the support seat (101) is provided with a support backing plate (102) slidingly, the output end of the driving member three (10) is fixed on the support seat (101), the driving member three (10) is connected with the support backing plate (102), and the placement seat (3) is installed on the support backing plate (102).

10. The pull-up type quick draw bench according to any one of claims 1-7, characterized in that: The sliding table (11) is provided with an avoiding hole one (111) avoiding the broach, and the tool plate (4) is provided with an avoiding hole two (41) avoiding the broach.

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