Erhu pull rod bending machine

Abstract

The invention discloses an Erhu pull rod bending machine, and relates to the technical field of musical instrument processing, and the Erhu pull rod bending machine comprises a rack, a controller, a first bending mechanism, a second bending mechanism, a bending angle adjusting mechanism and a hydraulic mechanism, the first bending mechanism, the second bending mechanism and a controller are arranged at the upper end of the rack, the bending angle adjusting mechanism is arranged on one side of the first bending mechanism, and the controller is connected with the hydraulic mechanism. Through the arrangement of the rack, the controller, the first bending mechanism, the second bending mechanism, the bending angle adjusting mechanism and the hydraulic mechanism, the bending angle and the bending shape of the end of the pull rod can be automatically and accurately controlled, and primary bending or secondary bending of the end of the pull rod can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of musical instrument processing, and in particular to an erhu tie rod bending machine. Background Art

[0002] The erhu is a traditional Chinese stringed instrument. It originated in the Tang Dynasty and was originally called the huqin. In modern times, it was renamed the erhu and began to develop vigorously. The erhu has a history of more than a thousand years since its creation. It is a very distinctive solo instrument. The traditional erhu generally includes a wooden sound box, a neck, strings and a bow. The end of the pull rod used with the erhu is generally in the shape of a single bend (one arc) or a double bend (two arcs), and the bending angle of the end of the erhu generally has strict requirements.

[0003] The bending method of the erhu drawbar in the prior art is to bend it by clamping it with a handheld clamp. This bending method cannot guarantee the bending angle and the bending shape. Moreover, for the drawbar with secondary bending, the bending is more difficult, and the bending angle and shape are more difficult to control. Summary of the invention

[0004] The purpose of the present invention is to provide an erhu tie rod bending machine to solve the above-mentioned technical problems.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A erhu tie rod bending machine comprises a frame, a controller, a first bending mechanism, a second bending mechanism, a bending angle adjustment mechanism and a hydraulic mechanism, wherein the hydraulic mechanism is arranged inside the frame, the first bending mechanism, the second bending mechanism and the controller are arranged at the upper end of the frame, the bending angle adjustment mechanism is arranged on one side of the first bending mechanism, and the controller is connected to the hydraulic mechanism;

[0007] The second bending mechanism comprises an end plate, a first swing arm mechanism, a second swing arm, a third swing arm, a first transmission shaft, a second transmission shaft, a first pressure rod, a second pressure rod, a first main bend pipe and a second main bend pipe, the two end plates are arranged opposite to each other at the upper end of the frame, the first transmission shaft, the first main bend pipe, the second main bend pipe and the second transmission shaft are arranged in sequence between the two end plates from top to bottom, one side of the end plate is provided with the second swing arm and the third swing arm, the other side of the end plate is provided with the first swing arm mechanism, the first swing arm mechanism is connected to the hydraulic mechanism, one end of the second swing arm and the first swing arm mechanism are connected to the two ends of the first transmission shaft, one end of the third swing arm and the first swing arm mechanism are connected to the two ends of the second transmission shaft, the two ends of the first pressure rod are connected to the other end of the second swing arm mechanism and the first swing arm mechanism, the two ends of the second pressure rod are connected to the other end of the third swing arm and the first swing arm mechanism, the first pressure rod and the second pressure rod are located on both sides of the first main bend pipe;

[0008] A plurality of first arc grooves are arranged on the outer wall of the first main curved tube, a plurality of second arc grooves are arranged on the outer wall of the second main curved tube, the first arc grooves are directly opposite to the second arc grooves, and a plurality of first annular grooves are arranged on the first pressure rod and the second pressure rod.

[0009] Preferably, the hydraulic mechanism includes a hydraulic station, a first oil cylinder and a second oil cylinder, the piston rod of the first oil cylinder is connected to the first swing arm mechanism, the piston rod of the second oil cylinder is connected to the bending mechanism, and the first oil cylinder and the second oil cylinder are respectively connected to the hydraulic station.

[0010] As a further preference, it also includes a first limit sensor, a second limit sensor, a first limit baffle and a second limit baffle. A first cylinder connecting piece is arranged on the piston rod of the first oil cylinder, and a second cylinder connecting piece is arranged on the piston rod of the second oil cylinder. The first limit sensor is arranged on both sides of the first oil cylinder, and the second limit sensor is arranged on both sides of the second oil cylinder. The first limit baffle is arranged on the first oil cylinder connecting piece, and the second limit baffle is arranged on the second oil cylinder connecting piece. The first limit baffle can contact the first limit sensor, and the second limit baffle can contact the second limit sensor. The hydraulic station, the first limit sensor and the second limit sensor are respectively connected to the controller.

[0011] Preferably, the first swing arm mechanism includes a first connecting arm, a second connecting arm and a third connecting arm, the middle part of the first connecting arm is connected to one end of the first transmission shaft, one end of the first connecting arm is connected to one end of the first pressure rod, one end of the second connecting arm is hinged to the other end of the first connecting arm, the other end of the second connecting arm is hinged to one end of the third connecting arm and one end of the second pressure rod, the middle part of the third connecting arm is connected to one end of the second transmission shaft, and the other end of the third connecting arm is connected to the hydraulic mechanism.

[0012] Preferably, it further includes a first heating tube sleeve, a clamping mechanism and a movable plate, wherein the movable plate is movably provided at the upper ends of the two end plates, and the lower end of the clamping mechanism passes through the movable plate and is connected to the first main bend pipe, and the first heating tube sleeve is provided on both the first main bend pipe and the second main bend pipe.

[0013] As a further preference, the clamping mechanism includes a threaded sleeve, a screw, a handle and a bolt top block, the threaded sleeve passes through the movable plate, the screw is arranged in the threaded sleeve, the upper end of the screw is provided with the handle, the upper end of the first main bend pipe is provided with the bolt top block, a positioning hole is opened on the bolt top block, and the lower end of the screw extends into the positioning hole.

[0014] Preferably, the bending mechanism comprises a connecting seat, a third transmission shaft, a third main bend pipe, a third pressure rod, a fourth swing arm and a fifth swing arm, the two connecting seats are arranged opposite to each other at the upper end of the frame, the third main bend pipe is arranged between the two connecting seats, a plurality of third arc grooves are arranged on the outer wall of the third main bend pipe, the third transmission shaft is arranged at the lower end of the third main bend pipe, the fourth swing arm is arranged on one of the connecting seats, the fifth swing arm is arranged on the other connecting seat, the two ends of the third pressure rod are connected to one end of the fourth swing arm and one end of the fifth swing arm, a plurality of second annular grooves are arranged on the outer wall of the third pressure rod, the other end of the fourth swing arm is connected to the hydraulic mechanism, and the two ends of the third transmission shaft are connected to the middle part of the fourth swing arm and the other end of the fifth swing arm.

[0015] As a further preference, the fourth swing arm is arranged in a "V" shape.

[0016] As a further preference, the bending angle adjustment mechanism includes a fixed block, a handwheel, a threaded column and a sliding block, the fixed block is arranged on one side of the third main bend pipe, the threaded column is threadedly connected to the fixed block, one end of the threaded column is connected to the handwheel, and the other end of the threaded column is connected to the sliding block, the sliding block is opposite to the third main bend pipe, and a plurality of first notches are opened on one side of the sliding block.

[0017] As a further preference, it further comprises a bottom plate, the bottom plate is arranged at the lower end of the sliding block, the bottom plate is connected to the frame, and the sliding block is slidably connected to the bottom plate.

[0018] The above technical solution has the following advantages or beneficial effects:

[0019] In the present invention, through the setting of the frame, the controller, the first bending mechanism, the second bending mechanism, the bending angle adjustment mechanism and the hydraulic mechanism, the bending angle and the bending shape of the end of the pull rod can be automatically and accurately controlled, and the end of the pull rod can be bent once or twice. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front view of the erhu tie rod bending machine of the present invention;

[0021] Figure 2 It is a top view of the erhu tie rod bending machine of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of the erhu tie rod bending machine in the present invention. Figure 1 ;

[0023] Figure 4 This is a schematic diagram of the structure of the erhu tie rod bending machine in the present invention. Figure 2 ;

[0024] Figure 5 This is a schematic diagram of the structure of the two-bending mechanism in the present invention. Figure 1 ;

[0025] Figure 6 This is a schematic diagram of the structure of the two-bending mechanism in the present invention. Figure 2 ;

[0026] Figure 7 This is a schematic diagram of the structure of a bending mechanism in the present invention. Figure 1 ;

[0027] Figure 8 This is a schematic diagram of the structure of a bending mechanism in the present invention. Figure 2 ;

[0028] Fig. 9 It is a structural schematic diagram of the bending angle adjustment mechanism in the present invention.

[0029] In the figure: 1, frame; 2, controller; 3, first bending mechanism; 301, connecting seat; 302, third transmission shaft; 303, third main bend pipe; 304, third pressure rod; 305, fourth swing arm; 306, fifth swing arm; 4, second bending mechanism; 401, end plate; 402, first swing arm mechanism; 403, second swing arm; 404, third swing arm; 405, first transmission shaft; 406, second transmission shaft; 407, first pressure rod; 408, second pressure rod; 409, first main bend pipe; 410, second main bend pipe; 411, first connecting arm; 412, second connecting arm; 413, third connecting arm; 414, first heating tube sleeve ;415, clamping mechanism;416, moving plate;417, threaded sleeve;418, screw;419, handle;420, bolt top block;5, bending angle adjustment mechanism;501, fixed block;502, hand wheel;503, threaded column;504, sliding block;505, bottom plate;506, first notch;507, second notch;6, hydraulic mechanism;601, hydraulic station;602, first oil cylinder;603, second oil cylinder;604, first limit sensor;605, second limit sensor;606, first limit baffle;607, second limit baffle;608, first oil cylinder connecting piece;609, second oil cylinder connecting piece. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if the terms "first", "second", "third" appear, they are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Figure 1 It is a front view of the erhu tie rod bending machine of the present invention; Figure 2 It is a top view of the erhu tie rod bending machine of the present invention; Figure 3 This is a schematic diagram of the structure of the erhu tie rod bending machine in the present invention. Figure 1 ; Figure 4 This is a schematic diagram of the structure of the erhu tie rod bending machine in the present invention. Figure 2 ; Figure 5 This is a schematic diagram of the structure of the two-bending mechanism in the present invention. Figure 1 ; Figure 6 This is a schematic diagram of the structure of the two-bending mechanism in the present invention. Figure 2 ; Figure 7 This is a schematic diagram of the structure of a bending mechanism in the present invention. Figure 1 ; Figure 8 This is a schematic diagram of the structure of a bending mechanism in the present invention. Figure 2 ; Fig. 9 Schematic diagram of the bending angle adjustment mechanism in the present invention. Figures 1 to 9 As shown, a preferred embodiment is shown, which shows an erhu tie rod bending machine, including a frame 1, a controller 2, a bending mechanism 3, a second bending mechanism 4, a bending angle adjustment mechanism 5 and a hydraulic mechanism 6. The frame 1 is provided with a hydraulic mechanism 6 inside, and the upper end of the frame 1 is provided with a bending mechanism 3, a second bending mechanism 4 and a controller 2. A bending angle adjustment mechanism 5 is provided on one side of the bending mechanism 3, and the controller 2 is connected to the hydraulic mechanism 6; in this embodiment, see Figure 3 As shown, the controller 2 may be a PLC controller 2, which is used to control the hydraulic mechanism 6, so that the hydraulic mechanism 6 can drive the first bending mechanism 3 and the second bending mechanism 4 to perform a bending action.

[0034] The hydraulic mechanism 6 is controlled by the controller 2, and then the first bending mechanism 3 and the second bending mechanism 4 are controlled by the hydraulic mechanism 6 to automatically bend the rod without manual operation. The end of the pull rod can be quickly bent, and the bending angle and shape can be controlled, which can improve work efficiency.

[0035] The second bending mechanism 4 includes an end plate 401, a first swing arm mechanism 402, a second swing arm 403, a third swing arm 404, a first transmission shaft 405, a second transmission shaft 406, a first pressure rod 407, a second pressure rod 408, a first main bend pipe 409 and a second main bend pipe 410. The two end plates 401 are arranged opposite to the upper end of the frame 1, and the first transmission shaft 405, the first main bend pipe 409, the second main bend pipe 410 and the second transmission shaft 406 are arranged between the two end plates 401 from top to bottom. The second swing arm 403 and the third swing arm 404 are arranged on one side of one end plate 401, and the first swing arm mechanism 402 is arranged on one side of the other end plate 401. The first swing arm mechanism 402 is connected to the hydraulic mechanism 6. One end of the second swing arm 403 and the first swing arm mechanism 402 are connected to the two ends of the first transmission shaft 405, one end of the third swing arm 404 and the first swing arm mechanism 402 are connected to the two ends of the second transmission shaft 406, the two ends of the first pressure rod 407 connect the other end of the second swing arm 403 mechanism and the first swing arm mechanism 402, the two ends of the second pressure rod 408 connect the other end of the third swing arm 404 and the first swing arm mechanism 402, the first pressure rod 407 and the second pressure rod 408 are located on both sides of the first main bend 409; in this embodiment, the lower ends of the two end plates 401 are fixed to the upper end of the frame 1 by bolts, and the two ends of the first transmission shaft 405 and the second transmission shaft 406 respectively pass through the two end plates 401. The second swing arm 403 is fixedly connected to the first transmission shaft 405, the third swing arm 404 is fixedly connected to the second transmission shaft 406, and the two ends of the first pressure rod 407 are rotatably connected to the first swing arm mechanism 402 and the second swing arm 403, the second pressure rod 408 is rotatably connected to the first swing arm mechanism 402 and the third swing arm 404, the first swing arm mechanism 402 can be connected to the piston rod of the first oil cylinder 602, and the hydraulic station 601 is controlled by the controller 2, so that the hydraulic station 601 controls the first oil cylinder 602 to drive the first swing arm mechanism 402 to rotate, the first swing arm mechanism 402 can drive the first transmission shaft 405 and the second transmission shaft 406 to rotate, and the second swing arm 403 and the third swing arm 404 follow the rotation, thereby controlling the first pressure rod 407 and the second pressure rod 408 to swing, thereby pressing down the pull rod, so that the pull rod is bent.

[0036] A plurality of first arc grooves are arranged on the outer wall of the first main curved tube 409, a plurality of second arc grooves are arranged on the outer wall of the second main curved tube 410, the first arc grooves are directly opposite to the second arc grooves, and a plurality of first annular grooves are arranged on the first pressure rod 407 and the second pressure rod 408. When in use, the end of the pull rod is extended from the upper side of the first pressure rod 407 into between the first main curved tube 409 and the second main curved tube 410, and then extended from the lower side of the second pressure rod 408, at which time the outer wall of the pull rod abuts against the inner wall of the first arc groove, the second arc groove and the first annular groove, and then the hydraulic station 601 controls the first oil cylinder 602 to drive the first swing arm mechanism 402 to rotate, and finally drives the second pressure rod 408 to press down, while the first pressure rod 407 pushes the pull rod upward, and cooperates with the limiting function of the first main curved tube 409 and the second main curved tube 410 to make the pull rod bend, and the swing angle of the first swing arm mechanism 402 is controlled to control the bending angle of the pull rod. Since the first main curved tube 409 and the second main curved tube 410 in this embodiment are both in the shape of an arc plate structure, the portions that can be bent by the pull rod are both in an arc shape. The second bending mechanism 4 in this embodiment makes the bending shape of the pull rod similar to an S shape.

[0037] Further, as a preferred embodiment, the hydraulic mechanism 6 includes a hydraulic station 601, a first oil cylinder 602 and a second oil cylinder 603, the piston rod of the first oil cylinder 602 is connected to the first swing arm mechanism 402, the piston rod of the second oil cylinder 603 is connected to a bending mechanism 3, and the first oil cylinder 602 and the second oil cylinder 603 are respectively connected to the hydraulic station 601. The hydraulic station 601 is used to provide power to the first oil cylinder 602 and the second oil cylinder 603, so that the piston rods of the first oil cylinder 602 and the second oil cylinder 603 can be extended and retracted.

[0038] Further, as a preferred embodiment, it also includes a first limit sensor 604, a second limit sensor 605, a first limit baffle 606 and a second limit baffle 607. A first cylinder connecting piece 608 is provided on the piston rod of the first oil cylinder 602, and a second cylinder connecting piece 609 is provided on the piston rod of the second oil cylinder 603. The first limit sensor 604 is provided on both sides of the first oil cylinder 602, and the second limit sensor 605 is provided on both sides of the second oil cylinder 603. The first limit baffle 606 is provided on the first cylinder connecting piece 608, and the second limit baffle 607 is provided on the second cylinder connecting piece 609. The first limit baffle 606 can contact the first limit sensor 604, and the second limit baffle 607 can contact the second limit sensor 605. The hydraulic station 601, the first limit sensor 604 and the second limit sensor 605 are respectively connected to the controller 2. By setting the first limit baffle 606 and the two first limit sensors 604, the stroke of the piston rod of the first oil cylinder 602 can be limited, and by setting the second limit baffle 607 and the second limit sensor 605, the stroke of the piston rod of the second oil cylinder 603 can be limited. The first limit sensor 604 and the second limit sensor 605 are respectively connected to the controller 2. When the first limit sensor 604 and the second limit sensor 605 detect the first limit baffle 606 and the second limit baffle 607, the controller 2 can automatically control the hydraulic station 601 so that the hydraulic station 601 controls the first oil cylinder 602 or the second oil cylinder 603 to stop working.

[0039] Further, as a preferred embodiment, the first swing arm mechanism 402 includes a first connecting arm 411, a second connecting arm 412 and a third connecting arm 413, the middle part of the first connecting arm 411 is connected to one end of the first transmission shaft 405, one end of the first connecting arm 411 is connected to one end of the first pressure rod 407, one end of the second connecting arm 412 is hinged to the other end of the first connecting arm 411, the other end of the second connecting arm 412 is hinged to one end of the third connecting arm 413 and one end of the second pressure rod 408, the middle part of the third connecting arm 413 is connected to one end of the second transmission shaft 406, and the other end of the third connecting arm 413 is connected to the hydraulic mechanism 6. Among them, the first connecting arm 411 and the first pressure rod 407 are rotatably connected, and the second connecting arm 412 and the first connecting arm 411 as well as the third connecting arm 413 and the second pressure rod 408 are all rotatably connected, so that the first pressure rod 407 and the second pressure rod 408 can rotate. In the process of pressing the pull rod, the first pressure rod 407 and the second pressure rod 408 can rotate, reducing the contact friction with the pull rod, protecting the surface of the pull rod, and facilitating the bending of the pull rod.

[0040] Further, as a preferred embodiment, it also includes a first heating sleeve 414, a clamping mechanism 415 and a movable plate 416. The upper ends of the two end plates 401 are movably provided with movable plates 416. The lower ends of the clamping mechanism 415 pass through the movable plates 416 and are connected to the first main bend 409. The first heating sleeve 414 is provided on both the first main bend 409 and the second main bend 410. The first heating sleeve 414 can be connected to the controller 2. The controller 2 controls the first heating sleeve 414 to heat the first main bend 409 and the second main bend 410, so that the first main bend 409 and the second main bend 410 can heat the tie rod, which is more conducive to the bending of the tie rod. In this embodiment, both ends of the first main bend 409 and the second main bend 410 are connected to the two end plates 401.

[0041] Further, as a preferred embodiment, the clamping mechanism 415 includes a threaded sleeve 417, a screw rod 418, a handle 419 and a bolt top block 420. The threaded sleeve 417 passes through the movable plate 416, the screw rod 418 is arranged in the threaded sleeve 417, the upper end of the screw rod 418 is provided with a handle 419, and the upper end of the first main curved tube 409 is provided with a bolt top block 420. A positioning hole is provided on the bolt top block 420, and the lower end of the screw rod 418 extends into the positioning hole. The handle 419 controls the rotation of the screw rod 418 so that the screw rod 418 can extend into the positioning hole, thereby squeezing the first main curved tube 409 downward, so that the first main curved tube 409 can press the pull rod, and the structure is more stable. Among them, the bolt top block 420 is against the upper end of the first main curved tube 409 and can be separated from each other. The threaded sleeve 417 is fixedly connected to the movable plate 416. There are strip holes at both ends of the connecting plate, and bolt holes are set at the upper end of the end plate 401. Bolts pass through the strip holes and connect with the bolt holes. When the bolts are tightened, the movable plate 416 can be fixed. When the bolts are loosened, the movable plate 416 can be moved, which is convenient for adjusting the position. When the position needs to be adjusted, the bolt top block 420 can be moved to the specified position first, and then the movable plate 416 can be controlled to move, driving the threaded sleeve 417 and the screw rod 418 to move, so that the lower end of the screw rod 418 can be inserted into the positioning hole on the bolt top block 420. In this embodiment, see Figure 6 As shown, the third connecting arm 413 is arranged in a "V" shape. The third connecting arm 413 can be replaced with models with different middle angles. When the piston rod stroke of the first oil cylinder 602 is constant, the rotation amplitude of the first pressure rod 407 and the second pressure rod 408 can be changed, thereby controlling the bending angle of the pull rod.

[0042] Further, as a preferred embodiment, a bending mechanism 3 includes a connecting seat 301, a third transmission shaft 302, a third main bend pipe 303, a third pressure rod 304, a fourth swing arm 305 and a fifth swing arm 306. The two connecting seats 301 are arranged opposite to each other at the upper end of the frame 1, and the third main bend pipe 303 is arranged between the two connecting seats 301. A plurality of third arc grooves are arranged on the outer wall of the third main bend pipe 303, and a third transmission shaft 302 is arranged at the lower end of the third main bend pipe 303. The fourth swing arm 305 is arranged on one of the connecting seats 301, and the fifth swing arm 306 is arranged on the other connecting seat 301. Both ends of the third pressure rod 304 are connected to one end of the fourth swing arm 305 and one end of the fifth swing arm 306. A plurality of second annular grooves are arranged on the outer wall of the third pressure rod 304. The other end of the fourth swing arm 305 is connected to the hydraulic mechanism 6, and the two ends of the third transmission shaft 302 are connected to the middle part of the fourth swing arm 305 and the other end of the fifth swing arm 306. See also Figure 7 and Figure 8 As shown, the connection seat 301 can be connected to the upper end of the frame 1 by bolts, the third transmission shaft 302 passes through the two connection seats 301 and is rotatably connected to the connection seats 301, and the fourth swing arm 305 and the fifth swing arm 306 are connected and fixed to the third transmission shaft 302, and the other end of the fourth swing arm 305 is used to connect with the piston rod of the second oil cylinder 603, and the fourth swing arm 305 is driven to rotate by the second oil cylinder 603, thereby driving the third transmission shaft 302 to rotate, and the third transmission shaft 302 drives the fifth swing arm 306 to rotate, and then drives the third pressure rod 304 to rotate. Among them, a second heating pipe sleeve is arranged on the bottom wall of the third main curved pipe 303.

[0043] When the pull rod needs to be bent once, the end of the pull rod can be passed through the lower side of the third pressure rod 304, and then through the upper side of the third main bend pipe 303, so that the outer wall of the pull rod is against the inner wall of the third arc groove and the inner wall of the second annular groove. Then the hydraulic station 601 controls the second oil cylinder 603 to drive the fourth swing arm 305 to rotate, and finally drives the third pressure rod 304 to press the pull rod downward, cooperating with the third main bend pipe 303 to realize a single bending of the pull rod.

[0044] The first oil cylinder connecting member 608 on the first oil cylinder 602 is used to connect the third swing arm 404 , and the second oil cylinder connecting member 609 on the second oil cylinder 603 is used to connect the fourth swing arm 305 .

[0045] Furthermore, as a preferred embodiment, the fourth swing arm 305 is arranged in a "V" shape, and the fourth swing arm 305 can be disassembled and replaced, and can be replaced with models with different sizes of middle angles.

[0046] Further, as a preferred embodiment, the bending angle adjustment mechanism 5 includes a fixed block 501, a hand wheel 502, a threaded column 503 and a sliding block 504. The fixed block 501 is arranged on one side of the third main bend tube 303. The threaded column 503 is threadedly connected to the fixed block 501. One end of the threaded column 503 is connected to the hand wheel 502, and the other end of the threaded column 503 is connected to the sliding block 504. The sliding block 504 is opposite to the third main bend tube 303, and a plurality of first slots 506 are opened on one side of the sliding block 504. Among them, a base plate 505 is provided at the lower end of the sliding block 504, the base plate 505 is connected to the frame 1, the slider and the base plate 505 are slidably connected, the base plate 505 is L-shaped, and a plurality of second slots 507 are provided on the base plate 505. The first slot 506 and the second slot 507 are opposite to each other to form a positioning slot. The end of the pull rod can be inserted into the early positioning slot, and the diameter of the positioning slot can be adjusted. By rotating the hand wheel 502, the threaded column 503 is driven to rotate, and the threaded column 503 moves forward to push the sliding block 504 to slide on the base plate 505. At this time, the sliding block 504 will push the end of the pull rod, and the bending angle of the pull rod can be fine-tuned during the bending process of the pull rod. For example, when the threaded column 503 pushes the sliding block 504 to move, the sliding block 504 will push the pull rod, increasing the bending angle of the pull rod. When the threaded column 503 retreats, the sliding block 504 will automatically retreat under the push of the end of the pull rod, and the bending angle of the end of the pull rod becomes smaller.

[0047] The sliding block 504 is provided with a strip groove, and the bottom plate 505 is provided with a bolt hole. Bolts pass through the strip holes and are connected to the bolt holes. Tightening the bolts can fix the position of the sliding block 504. When the bolts are loosened, the position of the sliding block 504 can be moved.

[0048] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A Erhu tie rod bending machine, characterized in that: The machine comprises a frame, a controller, a first bending mechanism, a second bending mechanism, a bending angle adjustment mechanism and a hydraulic mechanism, wherein the hydraulic mechanism is arranged inside the frame, the first bending mechanism, the second bending mechanism and the controller are arranged on the upper end of the frame, the bending angle adjustment mechanism is arranged on one side of the first bending mechanism, and the controller is connected to the hydraulic mechanism; The second bending mechanism comprises an end plate, a first swing arm mechanism, a second swing arm, a third swing arm, a first transmission shaft, a second transmission shaft, a first pressure rod, a second pressure rod, a first main bend pipe and a second main bend pipe, the two end plates are arranged opposite to each other at the upper end of the frame, the first transmission shaft, the first main bend pipe, the second main bend pipe and the second transmission shaft are arranged in sequence between the two end plates from top to bottom, one side of the end plate is provided with the second swing arm and the third swing arm, the other side of the end plate is provided with the first swing arm mechanism, the first swing arm mechanism is connected to the hydraulic mechanism, one end of the second swing arm and the first swing arm mechanism are connected to the two ends of the first transmission shaft, one end of the third swing arm and the first swing arm mechanism are connected to the two ends of the second transmission shaft, the two ends of the first pressure rod are connected to the other end of the second swing arm mechanism and the first swing arm mechanism, the two ends of the second pressure rod are connected to the other end of the third swing arm and the first swing arm mechanism, the first pressure rod and the second pressure rod are located on both sides of the first main bend pipe; A plurality of first arc grooves are arranged on the outer wall of the first main curved tube, a plurality of second arc grooves are arranged on the outer wall of the second main curved tube, the first arc grooves are directly opposite to the second arc grooves, and a plurality of first annular grooves are arranged on the first pressure rod and the second pressure rod.

2. The Erhu tie rod bending machine according to claim 1, characterized in that: The hydraulic mechanism includes a hydraulic station, a first oil cylinder and a second oil cylinder. The piston rod of the first oil cylinder is connected to the first swing arm mechanism, the piston rod of the second oil cylinder is connected to the bending mechanism, and the first oil cylinder and the second oil cylinder are respectively connected to the hydraulic station.

3. The Erhu tie rod bending machine according to claim 2, characterized in that: It also includes a first limit sensor, a second limit sensor, a first limit baffle and a second limit baffle. A first cylinder connecting piece is arranged on the piston rod of the first oil cylinder, and a second cylinder connecting piece is arranged on the piston rod of the second oil cylinder. The first limit sensor is arranged on both sides of the first oil cylinder, and the second limit sensor is arranged on both sides of the second oil cylinder. The first limit baffle is arranged on the first oil cylinder connecting piece, and the second limit baffle is arranged on the second oil cylinder connecting piece. The first limit baffle can contact the first limit sensor, and the second limit baffle can contact the second limit sensor. The hydraulic station, the first limit sensor and the second limit sensor are respectively connected to the controller.

4. The Erhu tie rod bending machine according to claim 1, characterized in that: The first swing arm mechanism includes a first connecting arm, a second connecting arm and a third connecting arm, the middle part of the first connecting arm is connected to one end of the first transmission shaft, one end of the first connecting arm is connected to one end of the first pressure rod, one end of the second connecting arm is hinged to the other end of the first connecting arm, the other end of the second connecting arm is hinged to one end of the third connecting arm and one end of the second pressure rod, the middle part of the third connecting arm is connected to one end of the second transmission shaft, and the other end of the third connecting arm is connected to the hydraulic mechanism.

5. The Erhu tie rod bending machine according to claim 1, characterized in that: It also includes a first heating tube sleeve, a clamping mechanism and a movable plate. The movable plate is movably arranged on the upper ends of the two end plates. The lower end of the clamping mechanism passes through the movable plate and is connected to the first main bend pipe. The first heating tube sleeve is arranged on the first main bend pipe and the second main bend pipe.

6. The Erhu tie rod bending machine according to claim 5, characterized in that: The clamping mechanism includes a threaded sleeve, a screw rod, a handle and a bolt top block. The threaded sleeve passes through the movable plate. The screw rod is arranged in the threaded sleeve. The upper end of the screw rod is provided with the handle. The upper end of the first main bend pipe is provided with the bolt top block. A positioning hole is opened on the bolt top block. The lower end of the screw rod extends into the positioning hole.

7. The Erhu tie rod bending machine according to claim 1, characterized in that: The bending mechanism includes a connecting seat, a third transmission shaft, a third main bend pipe, a third pressure rod, a fourth swing arm and a fifth swing arm. The two connecting seats are arranged opposite to each other at the upper end of the frame, the third main bend pipe is arranged between the two connecting seats, a plurality of third arc grooves are arranged on the outer wall of the third main bend pipe, the third transmission shaft is arranged at the lower end of the third main bend pipe, the fourth swing arm is arranged on one of the connecting seats, and the fifth swing arm is arranged on the other connecting seat, the two ends of the third pressure rod are connected to one end of the fourth swing arm and one end of the fifth swing arm, the outer wall of the third pressure rod is arranged with a plurality of second annular grooves, the other end of the fourth swing arm is connected to the hydraulic mechanism, and the two ends of the third transmission shaft are connected to the middle part of the fourth swing arm and the other end of the fifth swing arm.

8. The Erhu tie rod bending machine according to claim 7, characterized in that: The fourth swing arm is arranged in a "V" shape.

9. The Erhu tie rod bending machine according to claim 7, characterized in that: The bending angle adjustment mechanism includes a fixed block, a handwheel, a threaded column and a sliding block. The fixed block is arranged on one side of the third main bend pipe. The threaded column is threadedly connected to the fixed block. One end of the threaded column is connected to the handwheel, and the other end of the threaded column is connected to the sliding block. The sliding block is opposite to the third main bend pipe, and a plurality of first notches are opened on one side of the sliding block.

10. The Erhu tie rod bending machine according to claim 9, characterized in that: It also includes a bottom plate, the bottom plate is arranged at the lower end of the sliding block, the bottom plate is connected to the frame, and the sliding block is slidably connected to the bottom plate.

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