CN107470408B - Single swing arm left-right co-bending type numerical control pipe bending machine - Google Patents

Abstract

The invention relates to a single swing arm left-right co-bending type numerical control pipe bending machine, and belongs to the technical field of pipe processing. The numerical control pipe bending machine comprises a frame, a control unit, a feeding trolley, a machine head, a guide die unit and a switching unit, wherein the feeding trolley, the machine head, the guide die unit and the switching unit are arranged on the frame and controlled by the control unit; the machine head comprises a clamping die, a round die, a swing arm which drives a main shaft together with the round die, and a bending motor which drives the round die and the swing arm to bend and rotate and drive the round die and the swing arm to switch and rotate between a left bending position and a right bending position; the switching unit is controlled by the control unit to drive the machine head to move relative to the frame in the transverse direction and the vertical direction perpendicular to the axial direction of the pipe bending piece to drive the machine head to switch between the left pipe bending position and the right pipe bending position. The bending machine not only can realize left and right co-bending based on the single swing arm, but also can effectively improve the quality of the bent pipe, and can be widely applied to the fields of air conditioning, aviation and the like.

Description

Single swing arm left-right co-bending type numerical control pipe bending machine

Technical Field

The invention relates to pipe processing equipment, in particular to a single swing arm left-right co-bending type numerical control pipe bender.

Background

The numerical control pipe bender is widely applied to the industrial fields of air conditioners, automobiles, ships, aerospace and the like and mainly comprises a frame, a control unit, a feeding trolley, a guide die unit and a machine head, wherein the feeding trolley, the guide die unit and the machine head are arranged on the frame and controlled by the control unit; the machine head comprises a round die for controlling the radius of the pipe bending, a swing arm, a clamping die which is arranged on the swing arm and used for clamping a pipe fitting together with the round die, and a pipe bending motor which drives the round die and the swing arm to rotate around the rotation axis of a driving main shaft so as to perform pipe bending action on the pipe. According to different bending directions, the bending machine is divided into a left bending type pipe bending machine, a right bending type pipe bending machine and a left and right co-bending type pipe bending machine, and the left and right co-bending type pipe bending machine is commonly used for bending operation of complex pipelines.

The patent document with publication number of CN101817038A discloses a bending mechanism for constructing a left-right co-bending numerical control pipe bender, which comprises a support, a rotary gear rotatably arranged on the support, a motor for driving the rotary gear, a rotary bracket slidably arranged on the rotary gear, a left centering shaft and a right centering shaft slidably arranged on the rotary bracket through a sliding block, a left pin shaft and a right pin shaft which selectively extend into the left centering shaft and the right centering shaft, and a left pipe bending die and a right pipe bending die which are correspondingly connected on the left centering shaft and the right centering shaft; a rotary chute is arranged on one side of the rotary bracket, and a deflector rod extending into the rotary chute is fixedly arranged on the rotary gear; in the working process, the rotating shaft is switched by selectively connecting the centering shaft with the left pin shaft or the right centering shaft with the right pin shaft, so that one of the left pipe bending die and the right pipe bending die is a round die, and the other is a round die, thereby switching between a left bending working mode and a right bending working mode. Although the bending device can realize left and right co-bending, in order to avoid interference of the rotary gear on the bending process, two centering shafts are required to be far away from the rotary gear in height, and meanwhile, a swing arm and a die clamping mechanism arranged on the swing arm cannot be configured, so that the whole bending device is unstable easily to influence the bending quality.

Disclosure of Invention

The invention aims to provide a single swing arm left-right co-bending type numerical control pipe bending machine which can realize left-right co-bending based on a single swing arm and a single round die and can improve the quality of pipe bending.

In order to achieve the above purpose, the single swing arm left-right co-bending type numerical control pipe bender provided by the invention comprises a frame, a control unit, a pipe bending device and a feeding trolley, wherein the pipe bending device and the feeding trolley are arranged on the frame and controlled by the control unit, and the pipe bending device comprises a machine head, a guide die unit and a switching unit; the machine head comprises a left bending round die and a right bending round die which are arranged on a driving main shaft in a stacking manner, a swing arm which drives the main shaft together with the round die, a clamping die arranged on the swing arm, and a bending motor which is in transmission connection with the driving main shaft to drive the round die and the swing arm to bend and drive the round die and the swing arm to rotate in a switching manner between a left bending position and a right bending position; the round die cavities of the left-bending round die and the right-bending round die face opposite directions; the switching unit is controlled by the control unit to drive the machine head to move transversely and vertically relative to the machine frame in the axial direction perpendicular to the pipe bending piece to be bent, so as to drive the machine head to switch between the left pipe bending position and the right pipe bending position.

In the numerical control pipe bender, a round die on a machine head is arranged to be installed on a driving main shaft in a lamination mode by a left bending round die and a right bending round die which are opposite in direction of a round die cavity, meanwhile, a swing arm and the round die are arranged to be driven by a pipe bending motor to rotate around a rotation axis of the driving main shaft so as to reciprocally rotate between a left pipe bending position and a right pipe bending position, and a switching unit is used for driving a machine head to move in a transverse direction and a vertical direction perpendicular to the axial direction of a pipe bending workpiece so as to switch and move between the left pipe bending position and the right pipe bending position, so that the whole pipe bender can switch between left and right pipe bending modes, namely, the left and right co-bending can be realized on the basis of a single swing arm, and a pipe fitting is kept motionless in the transverse direction by only moving the machine head in the switching process of the pipe bending modes, so that unexpected shaking of the pipe fitting which is longer and has lower rigidity due to the switching of the pipe bending direction can be effectively avoided, and the pipe bending quality is ensured; meanwhile, more than one layer of left bending round die and right bending round die can be arranged on the driving main shaft, so that the requirements of more working conditions are met, and the forming efficiency of the bent pipe is improved.

The guide die unit comprises a guide die holder, a driving mechanism, a right bending guide die fixedly arranged on the right side of the guide die holder and a left bending guide die arranged on the left side of the guide die holder; the driving mechanism is controlled by the control unit to drive the guide die holder to move transversely so as to switch between the left bent pipe position and the right bent pipe position and move axially and reciprocally so as to assist the bending action; the switching unit is controlled by the control unit to drive the guided mode unit to synchronously move with the machine head.

Based on the configuration of the left and right guide die common guide die holders, two guide dies share one guide die driving mechanism, so that the number of parts is effectively reduced; meanwhile, when the right pipe bending operation is carried out, the whole guide die holder and the two guide dies are all positioned on the left side of the round die, and when the left pipe bending operation is carried out, the guide die holder and the two guide dies are all positioned on the right side of the round die, so that interference influence of the guide dies on the pipe bending operation in a left-right co-bending mode is effectively avoided.

The switching unit comprises a mounting seat arranged on the frame, a vertical sliding plate arranged on the mounting seat in a vertically sliding way through a linear guide rail, a transverse sliding plate arranged on the vertical sliding plate in a transversely sliding way through the linear guide rail, and a machine head arranged on the transverse sliding plate; the driving mechanism comprises a supporting seat which is arranged on the transverse sliding plate in a sliding way along the transverse direction through a linear guide rail, and the guide die holder is arranged on the supporting seat in a sliding way along the axial direction through the linear guide rail. The switching unit constructed based on the plate structure can effectively improve the compactness of the whole structure.

The other more specific scheme is that the round die cavity comprises an arc-shaped bent pipe section and a linear clamping section, and the direction of the linear clamping section on the left round die is opposite to that of the linear clamping section on the right round die; the left bending clamping die and the right bending clamping die project a non-overlapping surface area on a plane perpendicular to the axis of the driving spindle; the round die, the clamping die and the guide die which are matched with the round die form an adapting module, and the projection of two adapting modules arranged on adjacent layers on a plane parallel to the axis is free of overlapping surface areas. The clamping firmness of the pipe between the clamping die and the round die is effectively improved, and meanwhile, the connection between the guide die and the clamping die is effectively improved.

The preferred scheme is that a clamping die driving mechanism is arranged between a clamping die and a swing arm, the clamping die driving mechanism comprises a clamping die holder, a force increasing rocker, a force increasing connecting rod, a force increasing lever and an actuator, the clamping die holder is slidably arranged on the swing arm along an arc-shaped guide rail, and a stator of the actuator is hinged on the swing arm; the fixed end of the force-increasing rocker is hinged with the swing arm, and the swing end is hinged with the rotor of the actuator; the pivot of the force increasing lever is hinged on the swing arm, and the force applying end is hinged with the die holder; one end of the force increasing connecting rod is hinged with the swinging end of the force increasing rocker, and the other end of the force increasing connecting rod is hinged with the stress end of the force increasing lever; the arc guide rail and the swing track of the force application end have the same curvature radius, and the fulcrum of the force increasing lever is positioned at the lower side of the swing track adjacent to the driving main shaft.

The output force of the actuator of the clamping die driving mechanism based on the structure is amplified by the first level through the force-increasing rocker and the force-increasing connecting rod, amplified by the second level through the force-increasing lever and applied to the clamping die through the clamping die holder, so that the clamping force and the clamping stability of the clamping die and the round die on the pipe fitting are effectively ensured. Simultaneously, when the clamping die and the round die are opened to release the pipe fitting, the clamping die holder can pull the clamping die to retreat downwards along the arc-shaped guide rail to avoid the pipe fitting, so that the interference influence on the follow-up action of the pipe fitting is effectively avoided.

More preferable scheme is that the swing arm is provided with side guide plates clamped on two sides of the die holder, the arc guide rail is an arc chute arranged on the side guide plates, and two sides of the die holder are respectively provided with a slide block matched with the arc chute.

Based on the structure, the motion trail of the clamping die holder is limited through the side guide plates at two sides and the arc guide grooves, so that the stability of the motion of the clamping die holder, namely the stability of the clamping die in the process of clamping and releasing the pipe fitting, is effectively ensured.

The other preferable scheme is that the driving main shaft is in transmission connection with the bent pipe motor through a gear transmission device, and the gear transmission device comprises an input gear, a transition gear, an output gear and a gap adjusting mechanism; the input gear, the transition gear and the output gear are all helical gears; the gap adjusting mechanism comprises a first gap adjusting mechanism for adjusting the gap between the transition gear and the output gear and a second gap adjusting mechanism for adjusting the gap between the input gear and the transition gear; the first clearance adjusting mechanism comprises an eccentric shaft and an adjusting and locking mechanism for adjusting the corner of the eccentric shaft and locking the corner position of the eccentric shaft, and the transition gear is rotatably sleeved on the eccentric shaft.

Based on the transmission mechanism, the transition gear is sleeved on the eccentric shaft, so that the side gap between the transition gear and the output gear is adjusted by adjusting the rotation angle of the eccentric shaft, the parallelism of the rotating shaft of the transition gear before and after adjustment is effectively ensured, namely the transmission stability before and after gap adjustment is ensured; the fine adjustment of the center distance of the two gears is amplified to adjust the rotation angle of the eccentric shaft, so that the accuracy of the adjustment of the backlash between the gears is effectively improved; then, the adjustment of the side gap between the input gear and the transition gear is completed through a second gap adjusting mechanism; the problem that the side clearance of the transition gear of the three-stage gear set is not well adjusted in the prior art is solved, so that the requirement of the pipe bending machine on transferring heavy load in a large span is met, and the stability of the manufacturing precision of a product of the pipe bending machine constructed by the gear transmission device is improved.

The more preferable scheme is that the adjusting and locking mechanism comprises a fixed hole disc fixedly connected with a mounting seat of the machine head, a gear backlash adjusting hole disc synchronously and rotatably connected with one axial end of the eccentric shaft, and a locking pin selectively penetrating through a pair of locking holes arranged on the two hole discs.

The adjusting and locking mechanism based on the structure drives the gear backlash adjusting hole disc to rotate by rotating the eccentric shaft, obtains different corners of the eccentric shaft by pairing locking hole pairs at different positions, and realizes position locking by the locking pin, so that the whole mechanism has simple and compact structure; the interference to the pipe fitting in the pipe bending process can be further reduced.

Another more preferable scheme is that the second clearance adjusting mechanism comprises a mounting seat for mounting the input gear and an adjusting mechanism which is fixedly arranged on the mounting seat of the machine head and used for pushing the mounting seat to enable the input gear to move towards the direction close to the transition gear. The structure of the second gap adjusting mechanism is effectively simplified, so that interference to the pipe bending process is reduced.

A further preferred embodiment is that the control unit comprises a memory and a processor, the memory storing a computer program which, when executed by the processor, is capable of carrying out the steps of:

after the pipe bending operation in the first direction of the pipe fitting is completed, keeping the pipe fitting stationary relative to the frame in the transverse direction, controlling the first direction round die and the clamping die to open to release the pipe fitting, controlling the switching unit to drive the machine head to enable the first direction round die to deviate in the transverse direction so as to avoid the pipe fitting, and then driving the machine head to move downwards in the vertical direction to the top of the machine head so as to avoid the pipe fitting; controlling the bending motor to drive the round die and the swing arm to rotate around the rotation axis of the driving main shaft from the first direction bending position to the second direction bending position; the control switching unit drives the machine head to transversely move to the position above the position between the round die and the clamping die in the second direction, then drives the machine head to vertically and upwardly move to the same height as the round die and the pipe in the second direction, drives the machine head to transversely move to the position where the round die and the pipe are coaxially arranged, and then drives the clamping die to clamp the pipe, so that the pipe is subjected to second-direction pipe bending operation; one of the first direction round die and the second direction round die is a left-bending round die, and the other is a right-bending round die. The switching of the left and right pipe bending modes is realized through the step, and the pipe fitting shaking is avoided as much as possible in the switching process, so that the pipe bending quality is improved.

Drawings

FIG. 1 is a perspective view of embodiment 1 of the present invention;

FIG. 2 is an enlarged view of part of A of FIG. 1;

FIG. 3 is a perspective view of the feeding cart and the frame in embodiment 1 of the present invention;

fig. 4 is a perspective view of a switching unit in embodiment 1 of the present invention;

fig. 5 is a perspective view of the mold guiding unit of embodiment 1 of the present invention, with the transverse driving mechanism and the transverse rail-slider mechanism omitted;

FIG. 6 is a diagram showing the structure of the embodiment 1 of the present invention when the nose and the guide die unit are in the left bent pipe position;

FIG. 7 is a block diagram of a transverse driving mechanism and a transverse guide rail slider mechanism in a bent-tube motor, a gear transmission device and a guide die unit in embodiment 1 of the present invention;

FIG. 8 is a perspective view of a circular mold, swing arm and clamping mold assembly according to embodiment 1 of the present invention;

FIG. 9 is a diagram showing a structure of a clamping module and a swing arm in embodiment 1 of the present invention;

FIG. 10 is a schematic diagram showing a process of switching the clamping die from the released state to the clamped state in embodiment 1 of the present invention; fig. 10 (a) is a structural diagram of the release state, fig. 10 (b) is a structural diagram of the transition state, and fig. 10 (c) is a structural diagram of the clamping state;

FIG. 11 is a schematic diagram of a gear assembly and a motor for bending a tube according to embodiment 1 of the present invention;

FIG. 12 is an enlarged view of part B of FIG. 11;

FIG. 13 is an exploded view of the eccentric shaft and the adjusting and locking mechanism in embodiment 1 of the present invention;

fig. 14 is a schematic view showing the structure of a gear backlash adjustment hole disc in embodiment 1 of the present invention;

FIG. 15 is a schematic view showing the positional relationship between the pair of locking holes on the gear backlash adjustment hole disk and the fixed hole disk in embodiment 1 of the present invention;

FIG. 16 is a diagram showing the structure of the nose and the guide die unit in the right elbow position in embodiment 1 of the present invention;

FIG. 17 is an exploded view of the locking screw, locking pin and eccentric shaft of embodiment 2 of the present invention;

FIG. 18 is a schematic view showing the mounting position of the locking screw and the locking pin in embodiment 2 of the present invention;

FIG. 19 is a schematic view showing the structure of a gear backlash adjustment hole disc in embodiment 3 of the present invention;

FIG. 20 is a schematic view showing the structure of a fixed orifice disk in embodiment 3 of the present invention;

fig. 21 is a schematic view of the lever, the die holder and the guiding swing rod in embodiment 5 of the present invention.

Detailed Description

The invention is further described below with reference to examples and figures thereof.

Example 1

Referring to fig. 1 and 2, the numerical control pipe bender 1 comprises a frame 11, a control unit, a pipe bending device and a feeding trolley 2, wherein the pipe bending device and the feeding trolley are arranged on the frame 11 and controlled by the control unit; the pipe bending device comprises a switching unit 3, a guide die unit 4 and a machine head 5.

In this embodiment, the control unit includes a processor, a memory and a touch screen 12, where the processor receives an input instruction from an operator through the touch screen 12, and executes operations such as pipe bending and switching by executing a corresponding computer program stored in the memory to control the pipe bending device and the feeding trolley 2 to act.

Referring to fig. 3, the feed carriage 2 includes a feed rail 21 fixed to the frame 11, a feed slide table 22 slidably mounted on the feed rail 21 through a slider 210, a feed rack 23 fixed to the frame 11, a feed spindle 24 rotatably mounted on the feed slide table 22 about its own axis, a three-piece jaw 240 mounted at the front end of the feed spindle 24 and driven by a jaw cylinder 27, a rotary servo motor 25 for driving the feed spindle 24 to rotate, a feed servo motor 26 for driving the feed slide table 22 to reciprocate along the feed rail 21 by cooperation of a gear provided on the rotor shaft with the feed rack 23, and travel switches 28, 29 fixed to the frame 11 for controlling the travel of the feed slide table 22.

In the following description of specific structures of other units, the to-be-bent pipe is a pipe fitting clamped on the feeding main shaft 24, and in this embodiment, since the feeding main shaft is arranged along a horizontal direction, an axial direction of the to-be-bent pipe is arranged along the horizontal direction, and a transverse direction and a vertical direction perpendicular to the axial direction of the pipe fitting are respectively a horizontal direction and a vertical direction, that is, the transverse direction is perpendicular to the vertical direction.

Referring to fig. 4, the switching unit 3 includes a mounting plate 30, a vertical driving mechanism, a vertical linear rail 311, a vertical slider 312, a vertical slide plate 32, a lateral driving mechanism, a lateral linear rail 331, a lateral slider 332, a lateral slide plate 34, a lateral position detecting mechanism, and a vertical position detecting mechanism.

The vertical sliding plate 32 is vertically slidably mounted on the mounting plate 30 by cooperation of the vertical linear guide 311 and the vertical slider 312. The vertical driving mechanism comprises a servo motor 351, a screw rod 353 in transmission connection with the servo motor 351 through a synchronous belt 352, and a screw rod nut meshed with the screw rod 353; the screw 353 is rotatably installed on the mounting plate 30 and vertically arranged, and the screw nut is fixed on the vertical sliding plate 32, so that the vertical sliding plate 32 is driven to vertically reciprocate relative to the mounting plate 30 by the forward and reverse rotation of the servo motor 351.

The transverse slide plate 34 is mounted on the vertical slide plate 32 in a transversely sliding manner through the cooperation of the transverse linear guide rail 331 and the transverse slide block 332; the transverse driving mechanism comprises a servo motor 361, a screw rod 363 in transmission connection with the servo motor 361 through a synchronous belt 362, and a screw rod nut 364 meshed with the screw rod 363; a screw rod 363 is rotatably installed on the vertical sliding plate 32 and arranged in a lateral direction, and a screw rod nut 364 is fixed on the lateral sliding plate 34, so that the lateral sliding plate 34 is driven to reciprocate in a lateral direction with respect to the vertical sliding plate 32 by the forward and reverse rotation of the servo motor 361. That is, the transverse slide 34 can move in two dimensions relative to the mounting plate 30 in a vertical plane perpendicular to the axial direction of the workpiece to be bent under the pushing of the two driving mechanisms.

The transverse position detection mechanism comprises a first position travel switch 302 and a second position travel switch 303 which are arranged on the vertical sliding plate 32 through a mounting plate 301, and a travel switch trigger piece 304 which is fixedly arranged on the transverse sliding plate 34, and the relative position between the transverse sliding plate 34 and the vertical sliding plate 32 is monitored by touching the travel switch trigger piece 304 and the two travel switches; the vertical position detection mechanism is similar in structure to the lateral position detection mechanism, i.e., the relative position between the vertical slide 32 and the mounting plate 30 is monitored by two position travel switches.

Referring to fig. 5 to 7, the guide die unit 4 includes a guide die holder 41, a driving mechanism, two right-turn guide dies 42 fixed on the right side of the guide die holder 41, and one left-turn guide die 43 on the left side. The driving mechanism comprises a transverse guide rail sliding block mechanism, a transverse driving mechanism, a supporting seat 46, an axial oil cylinder 47 and an axial guide rail sliding block mechanism 48.

The transverse guide rail slide block mechanism is composed of a linear guide rail 44 which is arranged along the transverse direction and is arranged on the mounting seat 50, and a slide block 45 which can slide along the linear guide rail 44; the transverse driving mechanism comprises a servo motor 491, a screw rod 493 in transmission connection with the servo motor 491 through a synchronous belt 492 and a screw rod nut fixedly connected with the sliding block 45, so that the sliding block 45 is driven to reciprocate transversely relative to the mounting seat 50 through the forward and reverse rotation of the servo motor 491, and the supporting seat 46, the die guide seat 41, the axial oil cylinder 47, the left bending guide die 43 and the right bending guide die fixed on the sliding block 45 through the mounting seat 451 are pushed to slide transversely.

The guide die holder 41 is a linear-shaped frame structure, and the axial guide rail sliding block mechanism 48 comprises linear guide rails 481 which are fixedly arranged on two inner side walls of the linear-shaped frame structure and are axially arranged, and sliding blocks 482 which are fixedly arranged on the supporting base 46; the cylinder body of the axial cylinder 67 is fixedly connected with the supporting seat 46, and the cylinder rod 471 is fixedly connected with the door-shaped frame, so that the guide die holder 41 is pushed to reciprocate axially relative to the supporting seat 46.

Referring to fig. 6 to 8, the head 5 includes a mount 50, a swing arm 51, a round die 52, a clamping die 53, a clamping die driving mechanism 6, a bending motor 55, a driving spindle 54, and a gear transmission 7 forming a transmission connection between the bending motor 55 and the driving spindle 54. In this embodiment, three layers of round dies are mounted on the driving spindle 54 in a stacked manner, including a right round die 521, a left round die 522 and a right round die 523 with different radii of bending, where the radii of bending of the left round die 522 and the two right round dies may be the same or different, and depending on the actual working conditions, when the radii of bending of the round dies are changed, the extending lengths of the corresponding clamping dies and the guiding dies are also changed to match the round dies; the number of the left bending round dies and the right bending round dies is configured according to actual needs; the right round die 521 and the right round die 523 have the same round die cavity orientation and opposite round die cavities of the left round die 522, in this embodiment, the round die cavities of the three round dies are all in a U-shaped structure, that is, the round die cavities thereof include an arc-shaped bent pipe section for controlling the radius of the pipe fitting bent pipe and a straight line clamping section for clamping the end of the pipe fitting by matching with the clamping die, and taking the round die 522 as an example, the round die cavities thereof include a semicircular bent pipe section 5221 and a straight line clamping section 5222. The definition of the orientation of the round die cavity in the invention is that the connection point between the arc-shaped bent pipe section and the straight clamping section is taken as a starting point and the direction along which the straight clamping section extends; when the round die cavity is a U-shaped round die cavity, the orientation of the round die cavity can be defined as the opening orientation of the U-shaped structure; for other round die cavities, the round die cavity orientation in the invention refers to the opening orientation of a semicircular part of the bent pipe round die cavity taking the clamping position of the clamping die and the round die as the starting point. The clamping molds 53 are also provided with three corresponding clamping molds 531, 532 and 533, and their positions are distributed corresponding to the straight line clamping sections in the round mold cavity, so in this embodiment, in order to avoid interference between the clamping mold positions and the guide mold clamping positions, there is a projection non-overlapping surface area of the left and right clamping molds on a plane perpendicular to the axis of the driving spindle 54, and the positional relationship between the left and right clamping molds 532 and 533 is described as an example, where the axis of the driving spindle 54 is arranged vertically, the plane perpendicular to the axis is a horizontal plane, and the projection non-overlapping surface area of the left and right clamping molds 532 and 533 on the horizontal plane is defined as a straight line, and at this time, if the radii of the bends of the left and right round molds 522 and 523 are the same, the overlapping area of the two is at most a straight line, that is, the projection of the connecting line of the arc-shaped pipe section in the round mold cavity and the straight line clamping section on the horizontal plane.

As shown in fig. 6, 8 and 16, when the swing arm 51 is at the left bent pipe position shown in fig. 6, the straight clamping section of the left bent round die 522 is arranged to face outward; similarly, when the swing arm 51 is in the right bend position as shown in fig. 16, the straight clamping sections of the right bend round dies 521, 523 are also disposed outwardly, i.e., the left bend round die is oriented opposite the straight clamping sections of the right bend round die.

The round dies, the clamping dies and the guide dies which are arranged in the same layer form a group of adapting modules when seen from any round die and the clamping dies and the guide dies which are matched with the round die, namely, seen along the direction parallel to the axis of the driving main shaft 54, for example, the left bending round die 522, the left bending clamping die 532 and the left bending guide die 43 form an adapting module; in this embodiment, the left bending guide die, the right bending guide die, the left bending clamping die and the right bending clamping die are all installed in a layered manner, and the heights of the left bending guide die, the right bending guide die, the left bending clamping die and the right bending clamping die in the vertical direction are consistent with the heights of the corresponding round dies, that is, the same group of adaptation modules are distributed in the same layer. The projections of two sets of adaptation modules arranged on adjacent layers on a plane parallel to the axis of the driving spindle 54 have no overlapping surface area, so that only one set of clamping, round and guiding dies can be arranged on the same layer, namely, a left bending round die, a left bending clamping die, a left bending guiding die, a right bending round die, a right bending clamping die and a right bending guiding die cannot be simultaneously arranged on the same layer.

The head 5 is mounted together with the die guiding unit 4 by means of the mounting seat 50 to the transverse slide 34 as shown in fig. 4 for two-dimensional movement in a vertical plane perpendicular to the axial direction of the workpiece to be bent under the drive of the switching unit 3.

Referring to fig. 6, 8 and 9, the die-clamping driving mechanism 6 includes a die-clamping holder 60, a force-increasing rocker 621, a force-increasing link 622, a force-increasing lever 623 and an actuator 63, and three dies 53 of different bend radii are mounted in a stacked manner on a mounting surface 600 of the die-clamping holder 60, and a die-clamping adjusting screw 64 is rotatably mounted on an end of the swing arm 51 remote from the round die.

The actuator 63 is an oil cylinder, the oil cylinder rod 631 thereof constitutes a mover of the actuator 63, the cylinder body 632 constitutes a stator of the actuator 63, and the cylinder body 632 is hinged to the swing arm 51 through the hinge shaft 633.

The fixed end of the reinforcing rocker 621 is hinged with the swing arm 51 through a hinge shaft 651, and the swing end is hinged with the end part of the oil cylinder rod 631 through a hinge shaft 652; the pivot of the force increasing lever 623 is hinged on the swing arm 51 through a hinge shaft 653, and the force applying end is hinged with the die holder 60 through a hinge shaft 654; one end of the force increasing connecting rod 622 is hinged with the swinging end of the force increasing rocking rod 621 through a hinge shaft 652, namely the oil cylinder rod 631, the force increasing connecting rod 622 and the end part of the force increasing rocking rod 621 are hinged together through a hinge shaft 655, and the other end is hinged with the stress end of the force increasing lever 623.

Referring to fig. 8 to 10, the swing arm 51 includes side guide plates 627 clamped at both sides of the die holder 60, arc-shaped sliding grooves 629 are formed on inner sides of the side guide plates 627, and sliding blocks 628 matched with the arc-shaped sliding grooves 629 are respectively arranged at both sides of the die holder 60, so that lateral limit guidance and limit guidance on displacement in a vertical plane are performed on the movement process of the die holder 60 relative to the swing arm 51; and the arc-shaped sliding groove 629 is positioned below the swinging track of the force application end of the force increasing lever 623 in the vertical position so as to design the connection point layout of the die holder 60. As shown in fig. 10 (a), when the clamping die is in the open and releasing pipe state, the cylinder rod of the cylinder 63, the force-increasing rocker 621 and the force-increasing connecting rod 622 form a Y-shaped structure, and the lever 623 and the force-increasing connecting rod 622 are nearly collinear but are biased towards the direction deviating from the sliding block 628 by a small angle, namely, the included angle between the lever 623 and the force-increasing connecting rod is smaller than 180 degrees towards the arc-shaped sliding groove 629. At this time, the cylindrical rod-shaped slider 628 abuts against the lower groove end face of the arc-shaped chute 629.

As shown in fig. 10 (b), as the cylinder 63 is operated and pushes out the cylinder rod, it pushes the power rocker 621 and the power link 622 to move in a direction of being arranged in line, thereby pushing the force-receiving end of the power lever 623 to move in a direction of deviating from the arc chute 629, so as to push the die holder 60 to move in a direction approaching the round die through the force-applying end.

As shown in fig. 10 (c), as the cylinder 63 is pushed further, until the slider 628 slides along the arc-shaped sliding groove 629 to abut against the upper groove end surface thereof, that is, the clamping die is in a pipe clamping state, at this time, the force-increasing lever 623 is vertically arranged, and the force-increasing rocker 621 and the force-increasing connecting rod 622 are arranged in line, that is, the output force of the cylinder 63 is amplified by nearly infinite multiple, so as to provide the required clamping force for clamping the pipe clamping die.

In the above-mentioned clamping process, the sliding block 628 slides along the arc-shaped sliding groove 629, that is, the arc-shaped sliding groove 629 forms an arc-shaped guide rail for moving the clamping die holder 60 relative to the swing arm 51, in this embodiment, the center line of the arc-shaped sliding groove 629 and the axis of the hinge shaft 654 have a radius of curvature such as the swing track of the hinge shaft 653, that is, the radius of curvature such as the swing track of the arc-shaped guide rail and the force application end of the force increasing lever 623, so as to ensure that the clamping die holder 60 maintains a translational characteristic during the moving process.

Referring to fig. 11 to 13, the mounting seat 50 has a cavity structure with a mounting cavity 100, and the gear transmission device is a three-stage gear transmission device, including an input gear 741, a transition gear 757, an output gear 775, a first gap adjusting mechanism and a second gap adjusting mechanism; the first gap adjustment mechanism includes an eccentric shaft 76 and an adjustment locking mechanism; the three gears are helical gears.

The bent pipe motor 55 is fixed on the mounting plate 73 through four fixing bolts, the input gear 741 is sleeved on the output shaft of the bent pipe motor 55 through a flat key, eight waist round holes and two key grooves are formed in the mounting plate 73, the long axes of the waist round holes are parallel to the groove length direction of the key grooves, and the opening ends of the key grooves are arranged on the side end faces of the mounting plate 73; the bottom surface of the bottom plate 512 of the mounting seat 50 is provided with two key grooves matched with each other at the position corresponding to the key grooves, the mounting plate 73 is mounted on the bottom plate 512 by passing through a plurality of fixing bolts passing through the waist-round holes, and the corresponding key grooves on the two are connected through flat keys, at this time, the input gear 741 extends into and is positioned in the mounting chamber 100 through the through holes 510 arranged on the bottom plate 512, namely the mounting plate 73 forms the mounting seat of the input gear.

The second gap adjusting mechanism comprises a mounting plate 73, a fixed block 745 fixed on the bottom plate 512 and an adjusting screw 746 arranged along the long axis direction of the waist round hole, wherein the fixed block 745 is provided with a screw hole matched with the adjusting screw 746, and after the mounting is completed, the screw end surface of the adjusting screw 746 abuts against the side end surface of the mounting plate 73 so as to push the mounting plate 73 to move along the direction limited by the key and the key groove, namely, move along the long axis direction of the waist round hole by screwing the screw 746.

The eccentric shaft 76 includes a mounting shaft portion 761, a base shaft portion 762, and a mounting shaft portion 763, the axes of the mounting shaft portions 761, 763 being collinear; the end face of the mounting shaft portion 761 is provided with an inner hexagonal hole 7610 so as to facilitate the whole eccentric shaft 76 to rotate around the axis of the mounting shaft portion by screwing with an inner hexagonal wrench, i.e., to constitute an inner hexagonal adjustment hole; the axis of the base shaft 762 is parallel to, but not collinear with, the axis of the mounting shaft, and a transition gear 757 is rotatably journaled on the base shaft 762 by two bearings 756, 758 at the axial ends.

The adjusting and locking mechanism comprises an inner hexagonal hole 7610, a fixed hole disc 753 and a gear side gap adjusting hole disc 752, the fixed hole disc 753 is a round boss type ring body structure sleeved on the installation shaft part 763, the small diameter end face of the round boss type ring body structure is abutted against a shaft shoulder 7630 arranged on the installation shaft part 763, and a stepped through hole matched with the round boss type ring body structure is arranged on the bottom plate 512; the eccentric shaft 76 passes through the stepped through hole and then extends into the mounting chamber 100, so that the transition gear 757 is rotatably mounted in the mounting chamber 100 around the eccentric shaft 76; the mounting shaft 761 extends into and is in rotational engagement with a shaft hole 7140 provided in the top plate 514; the through-fixing hole plate 753 is fixed in the stepped through hole by a fixing screw 755.

The gear backlash adjustment hole disc 752 is sleeved on the mounting shaft portion 763 in a manner of synchronously rotating along with the eccentric shaft 76, in this embodiment, synchronous rotation is realized by matching an oblate hole 7520 formed on the gear backlash adjustment hole disc 752 with an oblate shaft portion 7631 formed on the mounting shaft portion 763, the gear backlash adjustment hole disc 752 is fixedly connected with the through-fixing hole disc 753 through a locking pin 7502, and the gear backlash adjustment hole disc 752 is tightly pressed on the fixing hole disc 753 through matching a round nut 751 with an external thread formed on the mounting shaft portion 763, so that locking of the corner position of the eccentric shaft 76 is realized.

The output gear 775 is synchronously rotatably mounted on the drive spindle 54 by two flat keys, both ends of the drive spindle 54 are rotatably mounted on the mount 50 by bearings 773 and 777, and the output gear 775 is also located in the mounting chamber 100.

After the completion of the installation work, the transition gear 757 is simultaneously meshed with the output gear 775 and the input gear 741.

Referring to fig. 13 to 15, six sets of locking holes 80 are provided on the gear backlash adjustment hole disc 752, a first hole set 81 to a sixth hole set 86 are provided in order clockwise, the first hole set 81 has three locking holes 80 with 15 degrees of central angles at intervals, that is, in the same hole set, the central angles at intervals between two adjacent locking holes are equal, and the central angles at intervals between the two locking holes and the sixth hole set 86 are 20 degrees; the second hole group 82 has four locking holes 80 with 15 degrees of spacing central angle, and 18 degrees of spacing central angle with the first hole group 81; the third hole group 83 has four locking holes 80 with 15 degrees of spacing central angle, and 20 degrees of spacing central angle with the second hole group 82; the fourth hole group 84 has three locking holes 80 with 15 degrees of central angle spacing, and 22 degrees of central angle spacing with the third hole group 83; the fifth hole group 85 has four locking holes 80 with 15 degrees of spacing central angle, and 20 degrees of spacing central angle with the fourth hole group 84; the sixth hole group 86 has four locking holes 50 with 15 degrees of central angle spacing, and 20 degrees of central angle spacing with the fifth hole group 85; the centers of these locking holes 80 are located on a circle concentric with the gear backlash adjustment hole disc 752.

And six locking holes 830 are uniformly arranged along the circumferential direction of the fixed hole disk 753, the locking holes 830 are pin holes matched with the locking pins 7502, namely, the circle where the circle centers of the six locking holes 830 are located is concentric with the fixed hole disk 753, and the central angle of the interval between every two adjacent locking holes is 60 degrees.

If the central angle 810 of the locking holes 830 adjacent to the first hole group 81 is 2.5 degrees, the central angles 820 of the intervals between the second locking holes 830 and the second hole group 82 are 15 degrees, the central angle 840 of the intervals between the third locking holes 830 and the third hole group 83 is 10 degrees, the central angle 850 of the intervals between the fourth locking holes 830 and the fourth hole group 84 is 5 degrees, the central angle 860 of the intervals between the fifth locking holes 830 and the fifth hole group 85 is 12.5 degrees, and the central angle 870 of the intervals between the sixth locking holes 830 and the sixth hole group 86 is 7.5 degrees, from which it can be seen that a pair of locking holes 80 and the locking holes 830 are aligned each time the rotation angle of the eccentric shaft 76 is rotated by 2.5 degrees by the hexagon socket head cap wrench, so that the relative positions between the eccentric shaft 76 and the mounting seat 50 can be locked by the locking screw 7502.

In the present embodiment, the center distance of the eccentric shaft 76 varies between-1.0 and 1.0, and since the adjustment angle of each stage is 2.5 °, the average adjustment accuracy of each stage can be calculated to be 2.5×2/360=0.0138, and it can be seen that the minute rotation on the center distance is converted into the angle value which is better measured, so as to reduce and adjust the magnitude of the machining error within the range of the adjustment accuracy which is generally required. The center distance between the transition gear 57 and the output gear 75 is adjusted by rotating the rotation angle of the eccentric shaft 6, i.e. the backlash between the two is adjusted.

As shown in fig. 11, the rotation angle of the adjusting screw 746 is adjusted to push the mounting plate 73 to move toward the input gear 741 and the transition gear 757, thereby achieving the purpose of adjusting the backlash therebetween.

Referring to fig. 6, 7, 8 and 16, the right bending round die 521, the left bending round die 522 and the right bending round die are coaxially sleeved on the driving main shaft 54 in a lamination manner, and in the embodiment of the invention, the lamination manner can be that the two are directly contacted in the axial direction, or a fixing or interval maintaining piece can be additionally arranged between the two; the fixed end 5100 of the swing arm 51 is also sleeved on the driving spindle 54, so that the driving spindle 54 drives the three round dies and the swing arm 51 to rotate around the rotation axis of the driving spindle 54, namely, the three round dies and the swing arm 51 drive the spindle together. The three clamping dies are coaxially arranged corresponding to the three round dies.

Referring to fig. 1 to 16, the specific process of performing the pipe bending operation on the pipe fitting to be bent by using the numerical control pipe bending machine is that a processor executes a computer program stored in a memory to realize the following steps:

the first direction pipe bending step is assumed to be a left pipe bending step, at this time, the positions of the three round dies, the guide die 4 and the three clamping dies are distributed as shown in fig. 6, that is, the direction from the feeding trolley 2 to the machine head 5 along the axial direction of the pipe workpiece to be bent, the swing arm 51, the clamping dies and the left bending guide die 43 are all positioned on the right side of the round dies, that is, they are positioned at the left pipe bending position, the pipe bending motor 55 is controlled to drive the swing arm 51, the clamping dies and the round dies to rotate towards the first direction through the driving spindle 54, pipe bending operation is performed on the pipe part clamped between the left bent round die and the corresponding clamping dies, and meanwhile, the feeding spindle 24 is controlled to drive the feeding spindle 24 and the guide die unit 4 to drive the left bending guide die 43 to synchronously move along the axial direction of the pipe.

In this step, the feeding trolley 2 enters a waiting position, a workpiece to be bent is fed into the clamping jaw 240 by an operator or an externally-added automatic feeding mechanism, and after the workpiece is pressed and started, the clamping jaw cylinder 27 acts to push the clamping jaw 240 to clamp the workpiece. The feeding servo motor 26 drives the feeding main shaft 24 through a gear rack mechanism to drive the pipe fitting to move on the guide rail, so that front and back feeding is realized.

The rotary servo motor 25 drives the feeding main shaft 24 to rotate through a synchronous belt, so that the pipe fitting is rotated. The feeding of the feeding trolley and the rotation of the main shaft are driven by the servo motor so as to ensure repeated positioning accuracy, and the use of the gear rack can effectively control noise while improving the bearing capacity of the feeding trolley.

After the pipe fitting is sent to the designated position by the feeding trolley 2, the oil cylinder 63 acts to push the die holder 60 to drive the die holder to move and approach the left-hand round die, so as to clamp the pipe fitting. At this time, the servo motor 491 in the guide die unit 4 acts to move the left bending guide die 43 to the corresponding working position to abut against the pipe fitting, and then the pipe bending motor 55 rotates to drive the swing arm to rotate synchronously with the round die, so that pipe bending operation is realized.

When the second pipe bending is required to be performed at the same die position, the clamping die and the left bending guide die 43 are loosened, the feeding trolley 2 can push the pipe fitting to move to a new position, if the pipe fitting is required to rotate a certain angle, the rotary servo motor 25 rotates to drive the feeding main shaft 24 to rotate, rotation of different angles of the pipe fitting is achieved, then the clamping die and the left bending guide die 43 are clamped, the swing arm 51 rotates, and the pipe bending at the same station is achieved again. The three-dimensional bent pipe is realized by the joint coordination of front and back feeding of the feeding trolley 2, rotation of the feeding main shaft 24 and rotation of the swing arm 51.

In the pipe bending process, the axial oil cylinder 47 pushes the guide die to act along the linear guide rail 481, so that the left bending guide die 43 and the swing arm synchronously move, and meanwhile, the feeding trolley 2 pushes the pipe fitting to synchronously move along with the swing arm 51, so that the pipe fitting is prevented from being pulled and deformed.

When the mould positions with different bending radii are needed to be used for realizing the switching of different bending diameters, a layer of left bending round mould with different bending radii is needed to be overlapped on the structure of the embodiment, the clamping mould and the left bending guide mould 43 are loosened, the servo motor 361 acts, the whole machine head is driven to move transversely through the transmission of the screw rod 363, the left bending round mould is slightly separated from a pipe fitting to avoid interference, then the servo motor 353 acts, the whole machine head 5 is driven to move up and down to the required mould position through the transmission of the screw rod 353, then the servo motor 361 moves, the other left bending round mould is aligned with the center of the feeding trolley 2, then the clamping mould and the left bending guide mould 43 are driven to clamp, and the swing arm 51 and the round mould are driven to move, so that the bending with different mould positions is realized.

A die changing step of transversely keeping the pipe fitting stationary relative to the frame 11, controlling the left bending round die, the clamping die and the left bending guide die 43 to open so as to release the pipe fitting, controlling the switching unit to drive the machine head 5 to enable the round die to deviate transversely so as to avoid the pipe fitting, and then driving the machine head 5 to vertically move downwards to the top of the machine head 5 so as to avoid the pipe fitting; the control pipe bending motor 55 drives the round die and the swing arm 51 to rotate from a first direction pipe bending position to a second direction pipe bending position around the rotation axis of the driving main shaft 54; the control switching unit drives the machine head 5 to transversely move to the position above the position between the right-hand bending round die and the corresponding clamping die, then drives the machine head 5 to vertically upwards move to the same height as the right-hand bending round die and the pipe, drives the machine head 5 to transversely move to the position where the right-hand bending round die and the pipe are coaxially arranged, and then drives the corresponding clamping die to clamp the pipe.

In the step, when reverse pipe bending is needed, namely, when right pipe bending is needed, the clamping die and the left bending guide die 43 are loosened, the servo motor 362 acts, the whole machine head is driven to move through the transmission of the screw rod 363, the left bending round die slightly leaves the pipe fitting to avoid interference, then the servo motor 351 acts, the whole machine head 5 is driven to move downwards to a designated position through the transmission of the screw rod 353, and interference between the pipe fitting and the top of the machine head 5 is avoided; then the pipe bending motor 55 acts to rotate the swing arm 51, the clamping die and the round die by 180 degrees around the axis of the driving spindle 54, so that the pipe bending motor 55 is driven by the pipe bending motor 55 to rotate and switch from the left pipe bending position to the right pipe bending position, namely, when the pipe bending direction is switched, the pipe bending motor 55 drives the round die and the swing arm 51 to rotate and switch between the left pipe bending position and the right pipe bending position through the driving spindle 54. Then, the servo motor 361 is controlled to drive the machine head 5 to transversely move to the position right above the position between the clamping die and the right bending round die, and the servo motor 491 is controlled to rotate so that the corresponding right bending guide die 42 is positioned at the left side of the right bending round die, and the interval between the two is used for ensuring that the machine head 5 cannot interfere with the pipe when ascending; then, the servo motor 351 is controlled to drive the machine head 5 to rise to the equal height position of the right bending round die and the pipe fitting, the servo motor 361 is controlled to drive the machine head 5 to move transversely to the coaxial arrangement of the right bending round die and the pipe fitting, then the driving oil cylinder 63 is driven to push the corresponding clamping die to clamp the pipe fitting, and the servo motor 491 is controlled to drive the left bending clamping die 42 to clamp the pipe fitting, at the moment, the positions of the round die, the guide die 4 and the clamping die are distributed as shown in fig. 16, namely, the direction from the feeding trolley 2 to the machine head 5 along the axial direction of the pipe fitting to be bent, and the swing arm 51, the clamping die and the right bending guide die 42 are all positioned at the left side of the round die, namely, the left side of the right bending die.

And in the second direction pipe bending step, the control pipe bending motor 55 is controlled to drive the swing arm 51 and the round die to rotate towards the second direction, pipe bending action is carried out on the pipe fitting part clamped between the right round die and the right clamping die, and meanwhile, the feeding trolley 2 is controlled to drive the feeding main shaft 24 and the guide die unit 4 to drive the right bending guide die to synchronously move along the axial direction. See first direction bend step for specific procedures.

After all the pipe bending actions are finished, the clamping die and the guide die 4 are loosened, the clamping jaw is loosened, after the bent product is manually taken down, the clamping die, the guide die, the feeding trolley and all the die positions are reset by pressing start, the initial position is returned, after the feeding is finished, the pressing start is carried out, and the actions are repeatedly realized.

Example 2

As an explanation of embodiment 2 of the present invention, only the differences from embodiment 1 described above, namely, only the structure of the clamping die assembly will be explained.

Referring to fig. 17 and 18, by providing a pin hole 5170 in the side wall plate of the mounting 50, in this embodiment, the adjustment locking mechanism further includes a lock pin 961 and a lock screw 962, the outer port portion of the pin hole 5170 is provided with a thread to be engaged with the lock screw 962, the inner end surface of the lock pin 961 is formed with an arc-shaped pressing surface 9610 to be engaged with the side wall surface of the mounting shaft portion 761 of the eccentric shaft 76, and the arc-shaped pressing surface 9610 of the lock pin 961 is pressed against the side wall surface of the mounting shaft portion 761 by the lock screw 962 to form a friction engagement surface to assist locking of the rotational angle position of the eccentric shaft 76.

Example 3

As an explanation of embodiment 3 of the present invention, only the differences from embodiment 1 described above will be explained below.

Referring to fig. 19 and 20, a plurality of locking holes (only two rings are shown) uniformly arranged in the radial direction may be provided on the fixed orifice plate 953, and each locking hole is uniformly arranged in the circumferential direction of the orifice plate. And a plurality of locking holes (only two circles are shown in the figure) with the same circle number and the same radial hole distance are arranged in the gear clearance adjusting hole disc 952, but interval central angle difference exists between two adjacent circles, so that the purpose of adjusting the rotation angle can be achieved by aligning the locking holes at different radial positions.

Example 4

As an explanation of embodiment 4 of the present invention, only the differences from embodiment 1 described above will be explained below.

The gear transmission is replaced by chain transmission to transmit rotation and force between the bent pipe motor and the driving main shaft, namely, gears are arranged on the driving main shaft and the bent pipe motor and are connected with each other through a toothed chain.

Example 5

As an explanation of embodiment 5 of the present invention, only the differences from embodiment 1 described above will be explained below.

Referring to fig. 21, instead of the arc-shaped chute of the above embodiment 1, by hinging one or more guide swing rods 964 on the mounting base, that is, hinging to the swing arm through a hinge shaft 965, the swing end of the guide swing rod 964 is hinged to the die holder 96 through a hinge shaft 966, and the guide swing rod 964 and the lever 963 are arranged in parallel during the swing, and the length thereof is equal to the length of the resistance arm of the lever 963. I.e. the swing track of the swing end of the guide swing rod 964 forms an arc-shaped guide rail for the movement of the die holder 96 relative to the mounting base.

In order to form the guide swing link 964 into a substantially planar swing surface during swing to improve the stability of the clamping die driving, at least one of the following structural designs may be adopted: the present invention is characterized in that (1) a substantially planar swing surface is formed by providing a lateral limit guide groove 962 for guiding the swing link 964 to pivot about its end hinge 966 on the die holder 96, that is, a groove wall of the lateral limit guide groove 962 abuts against a wall of the guide swing link 964 so as to slide along the groove wall, (2) a lateral limit guide groove for guiding the resistance arm of the lever 963 to pivot about its end hinge is provided on the die holder 96, and (3) a lateral limit guide groove for guiding the swing link 964 to pivot about its end hinge 965 is provided on the mount.

The linear motor and the cylinder are adopted to replace a power device for outputting linear displacement and force, such as an oil cylinder, and the like, as an actuator.

Example 6

As an explanation of embodiment 6 of the present invention, only the differences from embodiment 1 described above will be explained below.

The first clearance adjusting mechanism is formed by adopting a dividing disc mechanism to replace the adjusting and locking mechanism, namely, the dividing disc mechanism is utilized to realize the requirements of adjusting, dividing and positioning locking the rotation angle of the eccentric shaft.

The main conception of the invention is that the swing arm and the round die are driven to rotate by the pipe bending motor to perform pipe bending action and switch rotation between a left pipe bending position and a right pipe bending position, and the die changing unit is used for realizing the switch of the machine head between the left pipe bending position and the right pipe bending position, so that a single swing arm can be utilized to realize left and right co-bending, pipe fittings with complex pipe bending requirements can be processed, pipe bending processing is performed on the pipe fittings with relatively close two pipe bending positions, and pipe fittings subjected to pipe bending processing are subjected to pipe bending processing again; according to the present concept, there are also a number of obvious variations in the structure of the die changing unit and the die guiding unit; for the mold guiding unit, for example, two mold guiding mechanisms which act independently can be used for replacing the integral mold changing unit in the embodiment; for the die changing unit, the main function is to push the machine head to do two-dimensional motion on a plane perpendicular to the axial direction of the pipe fitting, but the machine head is not limited to a driving mechanism which can only do two-dimensional motion. In addition, the power sources in the die changing unit and the die guiding unit can also adopt power devices such as an air cylinder and a linear motor for outputting linear motion and force, and the structure is not limited to the structure in the embodiment.

Claims (6)

1. The single swing arm left-right co-bending type numerical control pipe bending machine comprises a frame, a control unit, a pipe bending device and a feeding trolley, wherein the pipe bending device and the feeding trolley are arranged on the frame and controlled by the control unit, and the pipe bending device comprises a machine head, a guide die unit and a switching unit;

the method is characterized in that:

the machine head comprises a left bending round die and a right bending round die which are arranged on a driving main shaft in a lamination mode, a swing arm which shares the driving main shaft with the round die, a clamping die arranged on the swing arm, and a bending motor which is in transmission connection with the driving main shaft to drive the round die and the swing arm to bend and rotate and switch and rotate between a left bending position and a right bending position; the round die cavities of the left-bending round die and the right-bending round die face opposite directions; the round die cavities of the left-bending round die and the right-bending round die are of U-shaped structures, and the round die cavities face in the direction of extending along the straight line section of the U-shaped structure by taking the connecting point of the U-shaped structure as a starting point; the connecting point is a connecting point between the arc-shaped section and the straight-line section of the U-shaped structure;

the switching unit is controlled by the control unit to drive the machine head to move transversely and vertically relative to the machine frame in the direction perpendicular to the axial direction of the pipe fitting to be bent, so as to drive the machine head to switch between a left bent pipe position and a right bent pipe position;

The guide die unit comprises a guide die holder, a driving mechanism, a right bending guide die fixedly arranged on the right side of the guide die holder and a left bending guide die arranged on the left side of the guide die holder;

the driving mechanism is controlled by the control unit to drive the guide die holder to move transversely so as to switch between a left bent pipe position and a right bent pipe position and move reciprocally along the axial direction to assist the bending action;

the switching unit is controlled by the control unit to drive the guided mode unit and the machine head to synchronously move;

the driving main shaft is in transmission connection with the bent pipe motor through a gear transmission device, and the gear transmission device comprises an input gear, a transition gear, an output gear and a gap adjusting mechanism;

the input gear, the transition gear and the output gear are all helical gears;

the gap adjusting mechanism comprises a first gap adjusting mechanism for adjusting the gap between the transition gear and the output gear and a second gap adjusting mechanism for adjusting the gap between the input gear and the transition gear;

the first clearance adjusting mechanism comprises an eccentric shaft and an adjusting and locking mechanism for adjusting the corner of the eccentric shaft and locking the corner position of the eccentric shaft, and the transition gear is rotatably sleeved on the eccentric shaft;

The adjusting and locking mechanism comprises a fixed hole disc fixedly connected with the mounting seat of the machine head, a gear backlash adjusting hole disc synchronously and rotatably connected with one axial end of the eccentric shaft, and a locking pin selectively penetrating through a pair of locking holes arranged on the two hole discs;

the second gap adjusting mechanism comprises an installation seat for installing the input gear and an adjusting mechanism which is fixedly arranged on the installation seat of the machine head and used for pushing the installation seat so as to enable the input gear to move towards the direction close to the transition gear.

2. The numerically controlled pipe bender according to claim 1, wherein:

the switching unit comprises a mounting plate arranged on the frame, a vertical sliding plate arranged on the mounting plate in a vertically sliding manner through a linear guide rail, a transverse sliding plate arranged on the vertical sliding plate in a transversely sliding manner through a linear guide rail, and the machine head is arranged on the transverse sliding plate;

the driving mechanism comprises a supporting seat which is arranged on the transverse sliding plate in a sliding way along the transverse direction through a linear guide rail, and the guide die holder is arranged on the supporting seat in a sliding way along the axial direction through the linear guide rail.

3. The numerically controlled pipe bender according to claim 1, wherein:

the circular die cavity comprises an arc-shaped bent pipe section and a linear clamping section, and the direction of the linear clamping section on the left bending circular die is opposite to that of the linear clamping section of the right bending circular die;

the projection of the left bending clamping die and the right bending clamping die on a plane perpendicular to the axis of the driving spindle is free of an overlapping surface area;

the round die, the clamping die and the guide die which are matched with the round die form an adapting module, and the projection of two groups of adapting modules which are arranged on adjacent layers on a plane parallel to the axis is free of overlapping surface areas.

4. A numerical control pipe bender according to any of claims 1-3, wherein:

a clamping die driving mechanism is arranged between the clamping die and the swing arm, the clamping die driving mechanism comprises a clamping die holder, a force increasing rocker, a force increasing connecting rod, a force increasing lever and an actuator, the clamping die holder is slidably arranged on the swing arm along an arc-shaped guide rail, and a stator of the actuator is hinged on the swing arm;

the fixed end of the boosting rocker is hinged with the swing arm, and the swing end is hinged with the rotor of the actuator; the pivot of the boosting lever is hinged to the swing arm, and the force application end is hinged to the die holder; one end of the force increasing connecting rod is hinged with the swinging end of the force increasing rocker, and the other end of the force increasing connecting rod is hinged with the stress end of the force increasing lever; the arc-shaped guide rail and the swing track of the force application end have the same curvature radius, and the fulcrum is positioned on the lower side of the swing track adjacent to the driving spindle.

5. The numerical control pipe bender according to claim 4, wherein:

the swing arm is provided with side guide plates clamped on two sides of the die holder, the arc guide rails are arc sliding grooves formed in the side guide plates, and sliding blocks matched with the arc sliding grooves are respectively arranged on two sides of the die holder.

6. A numerical control pipe bender according to any of claims 1-3, wherein the control unit comprises a memory and a processor, the memory storing a computer program which when executed by the processor is capable of performing the steps of:

after the pipe bending operation in the first direction of the pipe fitting is completed, keeping the pipe fitting stationary relative to the frame in the transverse direction, controlling the first direction round die and the clamping die to open to release the pipe fitting, controlling the switching unit to drive the machine head to enable the first direction round die to deviate in the transverse direction so as to avoid the pipe fitting, and then driving the machine head to move downwards in the vertical direction to the top of the machine head so as to avoid the pipe fitting; controlling the bending motor to drive the round die and the swing arm to rotate around the rotation axis of the driving main shaft from the first direction bending position to the second direction bending position; the control switching unit drives the machine head to transversely move to the position above the position between the second-direction round die and the clamping die, then drives the machine head to vertically and upwardly move to the same height as the second-direction round die and the pipe fitting, drives the machine head to transversely move to the second-direction round die and the pipe fitting to be coaxially arranged, then drives the clamping die to clamp the pipe fitting, and performs second-direction pipe bending operation on the pipe fitting;

One of the first direction round die and the second direction round die is a left-bending round die, and the other is a right-bending round die.