A bending knife device capable of automatically adjusting the length of a bending die and a bending machine

Abstract

The application discloses a bending small knife device and a bending machine capable of automatically adjusting the length of a bending die. The bending small knife device comprises a bending main tool holder, upper and lower bending tools installed on the upper and lower sides of a bending operation port of the bending main tool holder, and left and right side sub-tool holders fixed at the left and right ends of the bending main tool holder. A lower sub-bending tool mechanism capable of automatically adjusting the length of a tool is arranged at the bottom of the left and right side sub-tool holders. An upper sub-bending tool mechanism capable of automatically adjusting the length of a tool is arranged at the top of the left and right side sub-tool holders. The upper and lower bending tools can be used to bend general sheet metal parts. When special sheet metal parts need to be bent, the lower sub-bending tool mechanism and the upper sub-bending tool mechanism can be used to automatically assemble different tool lengths to correspond to the bending length for bending, thereby greatly improving the applicability and convenience of the bending small knife.

Description

Technical Field

[0001] This invention relates to the field of flexible automated sheet metal bending machine technology, and more specifically to a bending knife device and bending machine that can automatically adjust the length of the bending die. Background Technology

[0002] As labor costs rise, the demand for flexible and automated processing is increasing, and the sheet metal bending industry is no exception. Currently, most sheet metal automated bending equipment on the market uses bending dies of fixed dimensions or requires frequent manual changes of different lengths, resulting in low work efficiency. When a sheet metal section has both bending and non-bending sections on one side, it is necessary to manually change the bending die of the corresponding length, which brings considerable trouble to this special sheet metal processing.

[0003] Therefore, to solve the above problems, existing technologies such as CN218168456U-Bending Knife disclose a C-type bending tool mounting bracket. A linear guide pair is fixedly connected to the lower inner side of the C-type bending tool mounting bracket. Motor mounts are fixedly connected to both ends of the linear guide pair on both sides of the C-type bending tool mounting bracket. A servo motor is fixedly connected to the bottom of each motor mount. A knife mounting plate is slidably connected to the outer side of the linear guide pair. By setting the bending knife body, the servo motor drives the knife mounting plate to move via a synchronous belt. The knife mounting plate drives the bending knife body to a designated position, aligning the bending knife body with the bending position on one side of the C-type bending tool mounting bracket. This allows the bending knife body to directly bend the C-type bending tool mounting bracket without changing bending tools or performing other processing operations, significantly improving the efficiency of special bending operations.

[0004] However, the length of the aforementioned bending knife body is fixed and not adjustable. (See also: Special sheet metal part 100) Figure 1 When it is necessary to bend the first bending segment 200 and the second bending segment 300 of different lengths on one side, the above-mentioned bending knife mold is obviously not applicable and has certain limitations.

[0005] Therefore, how to provide a bending knife device and bending machine with an automatically adjustable bending die length that can flexibly and automatically adjust the bending length to improve ease of use is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides a bending knife device and bending machine with automatically adjustable bending die length that can flexibly and automatically adjust the bending length to improve ease of use.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A bending knife device with automatically adjustable bending die length, comprising:

[0009] A bending main tool holder, wherein an upper bending tool and a lower bending tool are respectively installed on the upper and lower sides of the bending working opening of the bending main tool holder, and a left auxiliary tool holder and a right auxiliary tool holder are respectively fixed at the left and right ends of the bending main tool holder;

[0010] The lower auxiliary bending tool mechanism has an automatically adjustable tool length and is located at the bottom of the left and right auxiliary tool holders.

[0011] The upper auxiliary bending tool mechanism and the lower auxiliary bending tool mechanism have automatically adjustable tool lengths and are located on top of the left and right auxiliary tool holders.

[0012] As can be seen from the above technical solution, compared with the prior art, the present invention discloses a bending knife device that can automatically adjust the length of the bending die. The upper bending knife and the lower bending knife can bend general sheet metal parts. When it is necessary to bend special sheet metal parts, the lower bending knife mechanism and the upper bending knife mechanism can be used to automatically assemble different knife lengths to correspond to the corresponding bending length for bending, which greatly improves the applicability and ease of use of the bending knife.

[0013] Furthermore, the lower auxiliary bending tool mechanism and the upper auxiliary bending tool mechanism have the same structure, and the lower auxiliary bending tool mechanism includes:

[0014] The lower guide rail has its two ends fixed to the lower mounting plates of the left and right auxiliary tool holders, respectively, and is arranged across the bending operation opening.

[0015] The left bending cutter assembly has an automatically adjustable cutter length and is slidably mounted on the lower guide rail.

[0016] The right-side bending cutter assembly has an automatically adjustable cutter length and is slidably mounted on the lower guide rail.

[0017] A left-side tool drive assembly is fixed on the left-side auxiliary tool holder and connected to the left-side bending tool assembly, used to drive the left-side bending tool assembly to move along the length direction of the lower guide rail;

[0018] The right-side tool drive assembly is fixed on the right-side auxiliary tool holder and connected to the right-side bending tool assembly, and is used to drive the right-side bending tool assembly to move along the length direction of the lower guide rail.

[0019] The beneficial effects of adopting the above technical solution are: the left-side tool drive assembly can drive the left-side bending tool assembly to move along the length direction of the lower guide rail, and the right-side tool drive assembly can drive the right-side bending tool assembly to move along the length direction of the lower guide rail, thereby realizing the bending operation of special sheet metal parts.

[0020] Furthermore, the left bending cutter assembly and the right bending cutter assembly have the same structure;

[0021] The right-side bending tool assembly includes:

[0022] The tool holders are multiple tool holders that are slidably connected to the lower guide rail. Two adjacent tool holders are detachably connected by a detachable structure. One of the tool holders is connected to the right-side tool drive assembly.

[0023] A right-side bending knife, wherein there are multiple right-side bending knives, each of which is fixed on a corresponding knife holder;

[0024] A right-side selection cylinder is fixed to the lower mounting plate. The telescopic end of the right-side selection cylinder is used to drive the detachable structure to separate the two adjacent tool holders.

[0025] The beneficial effects of adopting the above technical solution are as follows: when the bending knife needs to be adjusted to a certain bending length, the right-side knife drive assembly drives the knife holder to move to the position of the right-side selection cylinder. The extension and retraction end of the right-side selection cylinder drives the corresponding detachable structure to separate the two adjacent knife holders, thereby achieving the desired bending length as the length of the separated knife holder.

[0026] Furthermore, the detachable structure includes:

[0027] A fixed hook, one end of which is fixedly connected to one side of one of the tool holders, and the other end of which is a first hook end;

[0028] A screw, wherein the screw is inserted into a through hole inside another tool holder adjacent to the tool holder, and a mounting groove is provided on one side of the other tool holder, and the screw shank extends out of the mounting groove;

[0029] A floating button, one side of which is fixedly connected to the end of the screw, and the other side of which can abut against the telescopic end of the right-side selection cylinder. A floating hook is fixed on the floating button, and the floating hook can be placed in the placement groove. The floating hook has a second hook end, and the second hook end is hooked to the first hook end.

[0030] A spring is sleeved on the screw shaft, with its two ends abutting against the bottom of the through hole and one side of the floating button, respectively.

[0031] The beneficial effects of adopting the above technical solution are as follows: When it is necessary to separate two adjacent tool holders, the telescopic end of the right-side selection cylinder extends and presses the floating button. The floating hook on the floating button abuts against the bottom surface of the mounting slot. At this time, the floating hook disengages from the fixed hook, the spring is compressed, and thus the two adjacent tool holders are separated. Then, the right-side tool drive assembly drives the right-side bending knife, which has a certain bending length after separation, to move and bend the sheet metal part. Afterward, the telescopic end of the right-side selection cylinder retracts, and the floating button returns to its original position under the action of the spring. When it is necessary to assemble two adjacent tool holders together, the telescopic end of the right-side selection cylinder extends and presses the floating hook, bringing it closer to the adjacent tool holder. Then, the telescopic end of the right-side selection cylinder retracts, and the floating button re-hooks with the fixed hook under the action of the spring, realizing the assembly operation between the two adjacent tool holders. Therefore, this detachable structure can achieve the separation and combination of two adjacent tool holders using a fixed hook, screw, floating button, floating hook, and spring. The structure is simple, and both the fixed hook and the floating hook are set on the outside of the tool holder, making it easy to disassemble, assemble, and observe whether the hooking is correct.

[0032] Furthermore, the right-side bending tool assembly also includes a tool holder clamping mechanism, which includes:

[0033] A right-side clamping cylinder is fixed to the lower mounting plate and arranged close to the right-side selector cylinder.

[0034] The right pressure rod has one end hinged to the telescopic end of the right clamping cylinder, and the other end of the right pressure rod is fixed with a pressure block that presses against the knife holder.

[0035] Two pressure rod connecting plates are respectively disposed on both sides of the right pressure rod. One end of each pressure rod connecting plate is hinged to the clamping seat on the right pressure cylinder, and the other end is hinged to both sides of the right pressure rod.

[0036] The beneficial effects of adopting the above technical solution are as follows: when the right-side cutter drive assembly moves the right-side bending knife to the separation position, the right-side clamping cylinder actuates to drive the pressure block on the right-side pressure rod to press the cutter holder, which can quickly position and brake the right-side bending knife, preventing the right-side bending knife from failing to stop moving in time due to the inertia of the right-side cutter drive assembly, thereby ensuring that the right-side bending knife can accurately separate to the predetermined bending length under the action of the right-side selection cylinder. Furthermore, after the fixed hook and floating hook of two adjacent tool holders disengage, the right-side clamping cylinder can drive the pressure block to press the tool holder that is not involved in the bending work between the two adjacent tool holders. This is to avoid the adhesion between the two tool holders to be separated (in actual processing, some oily medium will inevitably adhere to the surface of the tool holder and the small knife, so that there is a certain adhesion between the two adjacent tool holders). When the right-side tool drive assembly drives the tool holder with the adjusted length to move, the moving tool holder at the separation position will cause the adjacent tool holder to move, which will reduce the positional accuracy of the small knife that is not involved in the bending. This will affect the fact that when the tool holder of the small knife involved in the bending returns to the separation position, it cannot hook into one with the tool holder of the small knife that is not involved in the bending.

[0037] Furthermore, the pressing surface of the pressing block is a rough surface.

[0038] The beneficial effects of adopting the above technical solution are: increasing the friction between the pressure block and the tool holder, and improving the braking efficiency of the tool holder.

[0039] Furthermore, the left-side tool drive assembly and the right-side tool drive assembly have the same structure;

[0040] The right-side tool drive assembly includes:

[0041] A right-side drive motor is fixed to the bottom surface of the lower mounting plate, and the drive shaft of the right-side drive motor extends upward from the lower mounting plate and is fixedly connected to the right-side drive pulley.

[0042] A left-side driven pulley is rotatably mounted on the lower side mounting plate of the left-side auxiliary tool holder;

[0043] A right-side drive belt is provided, with its two ends wound around the right-side driving pulley and the left-side driven pulley, respectively. A connecting plate is fixed to one side of one of the tool holders, and a belt clamping plate is detachably connected to the connecting plate. One side of the right-side drive belt is clamped and fixed between the connecting plate and the belt clamping plate.

[0044] The beneficial effects of adopting the above technical solution are: the right drive motor drives the right active pulley to rotate, and in conjunction with the left driven pulley, drives the right drive belt to move, thereby realizing the movement of the right bending knife on the lower guide rail.

[0045] Furthermore, the clamping surface of the belt clamping plate is a rough surface.

[0046] The beneficial effect of adopting the above technical solution is to avoid slippage of the right-side drive belt between the connecting plate and the belt clamping plate.

[0047] The present invention also provides a bending machine, including the bending knife device that can automatically adjust the length of the bending die. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0049] Figure 1 This is a schematic diagram of the bending structure of a special sheet metal part.

[0050] Figure 2 This is a first-view structural schematic diagram of a bending knife device that can automatically adjust the length of a bending die, as provided by the present invention.

[0051] Figure 3 This is a second-view structural schematic diagram of a bending knife device that can automatically adjust the length of a bending die, as provided by the present invention.

[0052] Figure 4 for Figure 3 A schematic diagram of the structure on the right-hand auxiliary tool holder.

[0053] Figure 5 This is a schematic diagram of the bending tool assembly on the right.

[0054] Figure 6 for Figure 5 A magnified schematic diagram of the structure of part A in the middle.

[0055] Figure 7 This is a schematic diagram of a detachable structure.

[0056] Figure 8 This is a schematic diagram of the floating button.

[0057] Figure 9 This is a top view of the left and right tool drive assemblies.

[0058] Figure 10 This is a schematic diagram of the tool holder clamping mechanism. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] like Figures 2-9 As shown, this embodiment of the invention discloses a bending knife device that can automatically adjust the length of the bending die, comprising:

[0061] The bending main tool holder 1 has an upper bending tool 2 and a lower bending tool 3 installed on the upper and lower sides of the bending working opening of the bending main tool holder 1, respectively. The left and right auxiliary tool holders 4 and 5 are fixed at the left and right ends of the bending main tool holder 1, respectively.

[0062] The lower auxiliary bending tool mechanism 6 has an automatically adjustable tool length and is located at the bottom of the left auxiliary tool holder 4 and the right auxiliary tool holder 5.

[0063] The cutting tool lengths of the upper auxiliary bending tool mechanism 7 and the lower auxiliary bending tool mechanism 6 can be automatically adjusted, and they are located on top of the left auxiliary tool holder 4 and the right auxiliary tool holder 5.

[0064] The lower bending tool mechanism 6 and the upper bending tool mechanism 7 have the same structure. The lower bending tool mechanism 6 includes:

[0065] The lower guide rail 61 is fixed at both ends to the lower mounting plates 8 of the left auxiliary tool holder 4 and the right auxiliary tool holder 5 respectively, and the lower guide rail 61 is arranged across the bending operation opening.

[0066] The left bending cutter assembly 62 has an automatically adjustable cutter length and is slidably mounted on the lower guide rail 61.

[0067] The right-side bending cutter assembly 63 has an automatically adjustable cutter length and is slidably mounted on the lower guide rail 61.

[0068] The left-side tool drive assembly 64 is fixed on the left-side auxiliary tool holder 4 and connected to the left-side bending tool assembly 62. It is used to drive the left-side bending tool assembly 62 to move along the length direction of the lower guide rail 61.

[0069] The right-side tool drive assembly 65 is fixed on the right-side auxiliary tool holder 5 and connected to the right-side bending tool assembly 63. It is used to drive the right-side bending tool assembly 63 to move along the length direction of the lower guide rail 61.

[0070] The left bending cutter assembly 62 and the right bending cutter assembly 63 have the same structure;

[0071] The right-side bending cutter assembly 63 includes:

[0072] Tool holders 631 are multiple tool holders 631 that are slidably connected to the lower guide rail 61. Two adjacent tool holders 631 are detachably connected by a detachable structure 632. One of the tool holders 631 is connected to the right tool drive assembly 65.

[0073] There are multiple right-side bending knives 633, each fixed to a corresponding knife holder 631.

[0074] The right-side selection cylinder 634 is fixed on the lower mounting plate 8. The telescopic end of the right-side selection cylinder 634 is used to drive the detachable structure 632 to separate the two adjacent tool holders 631.

[0075] The detachable structure 632 includes:

[0076] A fixed hook 6321 is provided, one end of which is fixedly connected to one side of a knife holder 631, and the other end of which is the first hook end 63211.

[0077] Screw 6322 is inserted into a through hole 6311 inside another tool holder 631 adjacent to tool holder 631. A mounting groove 6312 is provided on one side of the other tool holder 631, and the screw 6322 is arranged through the mounting groove 6312.

[0078] A floating button 6323 is fixedly connected to the screw end of a screw 6322 on one side, and the other side of the floating button 6323 can abut against the telescopic end of a right-side selector cylinder 634. A floating hook 6324 is fixed on the floating button 6323. The floating hook 6324 can be placed in a mounting groove 6312. The floating hook 6324 has a second hook end 63241, which is hooked to the first hook end 63211.

[0079] Spring 6325 is sleeved on the screw shank of screw 6322. The two ends of spring 6325 abut against the bottom of the through hole 6311 and one side of the floating button 6323, respectively.

[0080] The right-side bending tool assembly 63 also includes a tool holder clamping mechanism 635, which includes:

[0081] Right-side clamping cylinder 6351 is fixed on the lower mounting plate 8 and arranged close to the right-side selection cylinder 634.

[0082] The right pressure rod 6352 has one end hinged to the telescopic end of the right clamping cylinder 6351, and the other end of the right pressure rod 6352 is fixed with a pressure block 6353 that presses against the tool holder 631.

[0083] There are two pressure rod connecting plates 6354, which are respectively set on both sides of the right pressure rod 6352. One end of each pressure rod connecting plate 6354 is hinged to the clamping seat 63511 on the right pressure cylinder 6351, and the other end is hinged to both sides of the right pressure rod 6352.

[0084] The pressing surface of the pressure block 6353 is a rough surface.

[0085] The left tool drive assembly 64 and the right tool drive assembly 65 have the same structure;

[0086] The right-side tool drive assembly 65 includes:

[0087] The right drive motor 651 is fixed on the bottom surface of the lower mounting plate 8. The drive shaft of the right drive motor 651 extends upward from the lower mounting plate 8 and is fixedly connected to the right drive pulley 652.

[0088] The left driven pulley 653 is rotatably mounted on the lower mounting plate 8 of the left auxiliary tool holder 4;

[0089] The right drive belt 654 has its two ends wound around the right drive pulley 652 and the left driven pulley 653 respectively. One of the tool holders 631 has a connecting plate 655 fixed on one side. The connecting plate 655 is detachably connected to a belt clamping plate 656. One side of the right drive belt 654 is clamped and fixed between the connecting plate 655 and the belt clamping plate 656.

[0090] The clamping surface of the belt clamping plate 656 is a rough surface.

[0091] The present invention provides a bending machine, including the bending knife device described above that can automatically adjust the length of the bending die.

[0092] This invention places bending tools at both ends of the bending main tool holder. When different lengths of bending are required in the middle of the sheet metal (see...), Figure 1 The bending cutter automatically adjusts the die length and moves to the designated position via a drive belt for bending. This is especially useful when bending special sheet metal parts (e.g.,...). Figure 1The process involves a drive motor that moves the bending cutter to a designated position based on the bending length. A selector cylinder then pushes the floating hook into the mounting slot, disengaging it from the fixed hook. This selects the desired mold length. The drive motor then moves the selected mold to the desired bending position for bending. After bending, the drive motor returns the bending mold to the disengaged position, the selector cylinder retracts, and the floating hook re-engages with the fixed hook. This process is repeated for other bending lengths, significantly improving the bending efficiency of special sheet metal parts.

[0093] Therefore, the bending knife device that can automatically adjust the length of the bending die solves the problem of needing to change dies during the flexible automated bending process of special sheet metal parts, and greatly improves the bending efficiency of special sheet metal parts.

[0094] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0095] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A bending knife device with automatically adjustable bending die length, characterized in that, include: The bending main tool holder (1) has an upper bending tool (2) and a lower bending tool (3) installed on the upper and lower sides of the bending operation port of the bending main tool holder (1), and a left auxiliary tool holder (4) and a right auxiliary tool holder (5) are fixed at the left and right ends of the bending main tool holder (1). The lower auxiliary bending tool mechanism (6) has an automatically adjustable tool length and is located at the bottom of the left auxiliary tool holder (4) and the right auxiliary tool holder (5). The upper auxiliary bending tool mechanism (7) and the lower auxiliary bending tool mechanism (6) have automatically adjustable tool lengths, and are located on top of the left auxiliary tool holder (4) and the right auxiliary tool holder (5); The lower auxiliary bending tool mechanism (6) and the upper auxiliary bending tool mechanism (7) have the same structure. The lower auxiliary bending tool mechanism (6) includes: The lower guide rail (61) is fixed at both ends on the lower mounting plates (8) of the left auxiliary tool holder (4) and the right auxiliary tool holder (5) respectively, and the lower guide rail (61) is arranged across the bending operation opening; The left bending cutter assembly (62) has an automatically adjustable cutter length and is slidably mounted on the lower guide rail (61). The right-side bending cutter assembly (63) has an automatically adjustable cutter length and is slidably mounted on the lower guide rail (61). The left-side tool drive assembly (64) is fixed on the left-side auxiliary tool holder (4) and connected to the left-side bending tool assembly (62), and is used to drive the left-side bending tool assembly (62) to move along the length direction of the lower guide rail (61); The right-side tool drive assembly (65) is fixed on the right-side auxiliary tool holder (5) and connected to the right-side bending tool assembly (63), and is used to drive the right-side bending tool assembly (63) to move along the length direction of the lower guide rail (61); The left bending cutter assembly (62) and the right bending cutter assembly (63) have the same structure; The right-side bending cutter assembly (63) includes: Tool holder (631), the tool holder (631) is a plurality of which are slidably connected to the lower guide rail (61), and two adjacent tool holders (631) are detachably connected by a detachable structure (632), and one of the tool holders (631) is connected to the right tool drive assembly (65); There are multiple right-side bending knives (633), each fixed to a corresponding knife holder (631). A right-side selection cylinder (634) is fixed on the lower mounting plate (8). The telescopic end of the right-side selection cylinder (634) is used to drive the detachable structure (632) to separate the two adjacent tool holders (631). The detachable structure (632) includes: A fixed hook (6321) is provided, one end of which is fixedly connected to one side of a knife holder (631), and the other end of which is a first hook end (63211). A screw (6322) is inserted into a through hole (6311) inside another tool holder (631) adjacent to the tool holder (631). A mounting groove (6312) is provided on one side of the other tool holder (631), and the screw (6322) extends out of the mounting groove (6312). A floating button (6323) is fixedly connected to the screw end of the screw (6322) on one side, and the other side of the floating button (6323) can abut against the telescopic end of the right-side selection cylinder (634). A floating hook (6324) is fixed on the floating button (6323), and the floating hook (6324) can be placed in the mounting groove (6312). The floating hook (6324) has a second hook end (63241), and the second hook end (63241) is hooked to the first hook end (63211). A spring (6325) is sleeved on the screw (6322), and the two ends of the spring (6325) abut against the bottom of the through hole (6311) and one side of the floating button (6323), respectively. The right-side bending tool assembly (63) also includes a tool holder clamping mechanism (635), which includes: Right-side clamping cylinder (6351) is fixed on the lower mounting plate (8) and arranged close to the right-side selection cylinder (634); The right pressure rod (6352) has one end hinged to the telescopic end of the right pressure cylinder (6351), and the other end of the right pressure rod (6352) is fixed with a pressure block (6353) that presses against the knife holder (631). There are two pressure rod connecting plates (6354), which are respectively disposed on both sides of the right pressure rod (6352). One end of each of the two pressure rod connecting plates (6354) is hinged to the clamping seat (63511) on the right pressure cylinder (6351), and the other end is hinged to both sides of the right pressure rod (6352).

2. The bending knife device with automatically adjustable bending die length according to claim 1, characterized in that, The pressing surface of the pressing block (6353) is a rough surface.

3. The bending knife device with automatically adjustable bending die length according to claim 1, characterized in that, The left-side tool drive assembly (64) and the right-side tool drive assembly (65) have the same structure; The right-side tool drive assembly (65) includes: The right drive motor (651) is fixed on the bottom surface of the lower mounting plate (8). The drive shaft of the right drive motor (651) extends upward from the lower mounting plate (8) and is fixedly connected to the right drive pulley (652). Left driven pulley (653), which is rotatably mounted on the lower mounting plate (8) of the left auxiliary tool holder (4); A right-side drive belt (654) is provided, with its two ends wound around the right-side driving pulley (652) and the left-side driven pulley (653), respectively. A connecting plate (655) is fixed to one side of one of the tool holders (631), and a belt clamping plate (656) is detachably connected to the connecting plate (655). One side of the right-side drive belt (654) is clamped and fixed between the connecting plate (655) and the belt clamping plate (656).

4. A bending knife device with automatically adjustable bending die length according to claim 3, characterized in that, The clamping surface of the belt clamping plate (656) is a rough surface.

5. A bending machine, characterized in that, Includes a bending knife device with automatically adjustable bending die length as described in any one of claims 1-4.

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