Handheld hydraulic pipe bending machine

Abstract

The utility model relates to the technical field of pipe bending machines, in particular to a handheld hydraulic pipe bending machine which comprises a hydraulic oil cylinder, the hydraulic oil cylinder is composed of an oil cylinder pipe and an oil cylinder piston installed in the oil cylinder pipe in a sliding mode, a pipe bending die is fixed to the outer end of the oil cylinder piston, the oil cylinder piston is of a hollow structure, and a tension spring is arranged in the oil cylinder piston. One end of the tension spring is fixed to the end, close to the pipe bending die, in the oil cylinder piston, the other end of the tension spring is fixed to the end, away from the pipe bending die, in the oil cylinder pipe, and a clamping plate mounting base is fixed outside the end, close to the pipe bending die, of the oil cylinder pipe. The device has the beneficial effects that the cover plate capable of being driven by the oil cylinder piston to move is arranged at the end of the oil cylinder pipe, and the pressure release valve pull rod capable of controlling the manual pressure release valve to be opened is installed on the cover plate, so that after the oil cylinder piston reaches the end, the manual pressure release valve is automatically driven by the pressure release valve pull rod to be opened for pressure release, and the oil cylinder piston is prevented from continuously extending; the piston of the oil cylinder can be protected, automatic limiting can be achieved, and the using effect is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of pipe bender, in particular to a handheld hydraulic pipe bender. Background Art

[0002] Pipe bending machines can be roughly divided into CNC pipe bending machines, hydraulic pipe bending machines, etc.; they are mainly used for laying and repairing pipes in power construction, road and railway construction, boilers, bridges, ships, furniture, decoration, etc.; their disadvantage is that the bending angle of the metal pipe cannot be accurately controlled during the bending process. At the same time, most pipe bending machines are automated or semi-automated, with too complex structures and expensive processing, and are not suitable for processing some small amounts of pipes.

[0003] Chinese patent application number 201710519753.7 discloses a manual hydraulic pipe bender comprising a hydraulic cylinder, an upper clamping plate, a lower clamping plate, a movable stopper, a pipe bending die, and a handle. An upper clamping plate mounting seat is provided on one end of the hydraulic cylinder, and a handle mounting seat is provided on the other end of the hydraulic cylinder. The lower clamping plate is bolted to the lower side of one end of the hydraulic cylinder located on the upper clamping plate mounting seat. An angle ruler is provided on the upper surface of the upper clamping plate. A pair of connecting arms are provided on one side of the upper clamping plate, each of which is provided with a connecting shaft. The connecting arms are connected to the upper clamping plate mounting seat via the connecting shaft. Two movable stoppers are provided. In the above patent, when performing a pipe bending operation, the user needs to rely on experience and visual observation to determine whether the pipe bending die has reached the set telescopic length of the hydraulic cylinder, and then decide whether to release the pressure, which is very inconvenient. Utility Model Content

[0004] The utility model proposes a handheld hydraulic pipe bender in order to solve the above problems.

[0005] The technical solution of the present utility model is achieved as follows:

[0006] After derrick hoists and puts in place, stamp fixedly derrick of derrick pin, make hydraulic oil lead to the base hydraulic oil cylinder, hoist that base puts in place and fixing with same control mode. The clamping plate mounting seat is formed with an annular groove on the side facing the pipe bending mold, and a cover plate is slidably installed in the annular groove. A number of through holes are formed on the cover plate, and limit screws are arranged in the through holes. The end of the limit screw away from the cap head is fixed to the clamping plate mounting seat by means of a thread, and a return spring is nested on the outside of the end of the limit screw close to the cap head, and one end of the return spring rests on the cover plate. A piston spacer is slidably installed on the end of the cylinder tube close to the pipe bending mold, and the cylinder piston is slidably fitted with the piston spacer. A pressure relief valve pull rod is fixed to the cover plate through a detachable connection, and the other end of the pressure relief valve pull rod is connected and fixed to the pressure relief valve inside the manual pressure relief valve.

[0007] Furthermore, a pressure relief handle is installed on the side wall of the manual pressure relief valve, and a pressure relief valve connected to the pressure relief handle is arranged inside the manual pressure relief valve. Two pressure relief valves connected to the pressure relief valve pull rod and the pressure relief handle are arranged in parallel inside the manual pressure relief valve.

[0008] Furthermore, the limiting mechanism includes a lower card plate and an upper card plate, the lower card plate is fixed under the card plate mounting seat, a connecting arm is fixed to one side of the upper card plate, and the end of the connecting arm away from the upper card plate is fixed to the card plate mounting seat by a pin shaft, and two movable limiting parts are installed between the lower card plate and the upper card plate through a detachable connection, and the two movable limiting parts are symmetrically arranged on both sides of the pipe bending mold.

[0009] Furthermore, the lower clamping plate and the upper clamping plate are formed with a plurality of adjustment holes for adjusting the installation position of the movable limiting member.

[0010] Furthermore, a handle mounting base is fixed to one end of the hydraulic cylinder close to the manual pressure relief valve, and a hydraulic motor, an oil storage tank and an auxiliary handle are fixed on the handle mounting base. A switch button for controlling the operation of the hydraulic motor and a power cord for power supply are fixed on the auxiliary handle. The hydraulic motor and the oil storage tank are connected to the hydraulic cylinder and the manual pressure relief valve through an oil circuit.

[0011] Furthermore, universal rollers are installed at the bottom of the handle mounting base and below both ends of the lower clamping plate through detachable connections.

[0012] By adopting the above technical solution, the beneficial effects of the utility model are as follows: by arranging a cover plate at the end of the cylinder tube that can be driven to move by the cylinder piston, and installing a pressure relief valve pull rod that can control the opening of the manual pressure relief valve on the cover plate, the manual pressure relief valve is automatically driven to open by the pressure relief valve pull rod to relieve pressure after the cylinder piston reaches the end, thereby preventing the cylinder piston from continuing to extend, which can not only protect the cylinder piston, but also achieve automatic limiting, thereby improving the use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0014] Figure 1 It is the first stereogram of the present utility model;

[0015] Figure 2 It is a second stereogram of the present utility model;

[0016] Figure 3 It is an exploded view of the utility model;

[0017] Figure 4 It is a top view of the utility model;

[0018] Figure 5 It is a side view of the utility model;

[0019] Figure 6 It is a cross-sectional view of the present utility model.

[0020] The following are the descriptions of the reference numerals:

[0021] 1. Handle mounting base; 2. Hydraulic cylinder; 21. Cylinder tube; 22. Cylinder piston; 23. Tension spring; 24. Piston spacer; 3. Auxiliary handle; 4. Clamp mounting base; 5. Pipe bending die; 6. Limit mechanism; 61. Lower clamping plate; 62. Connecting arm; 63. Upper clamping plate; 64. Adjustment hole; 65. Movable limiter; 7. Manual pressure relief valve; 8. Universal roller; 9. Cover plate; 10. Pressure relief valve pull rod; 11. Return spring; 12. Limit screw. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0023] like Figures 1-6 As shown, a handheld hydraulic pipe bender includes a hydraulic cylinder 2. A manual pressure relief valve 7 connected to the internal oil circuit of the hydraulic cylinder 2 is fixed on the side wall of the rear end of the hydraulic cylinder 2 to facilitate pressure relief and contraction of the hydraulic cylinder 2. The hydraulic cylinder 2 consists of a cylinder tube 21 and a cylinder piston 22 slidably mounted therein. A pipe bending mold 5 is fixed to the outer end of the cylinder piston 22. The pipe bending mold 5 is provided with a variety of models, which can make the device suitable for a variety of different types of pipes. The cylinder piston 22 is a hollow structure. A tension spring 23 is provided inside the cylinder piston 22. One end of the tension spring 23 is fixed to The inside of the oil cylinder piston 22 is close to one end of the pipe bending mold 5, and the other end of the tension spring 23 is fixed to the end of the oil cylinder tube 21 away from the pipe bending mold 5. The tension spring 23 can make the oil cylinder piston 22 automatically retract into the oil cylinder tube 21 under the pressure relief state. A card plate mounting seat 4 is fixed to the outside of the end of the oil cylinder tube 21 close to the pipe bending mold 5. A limiting mechanism 6 for positioning the pipe fitting is installed on the side of the card plate mounting seat 4 facing the pipe bending mold 5. An annular groove is formed on the side of the card plate mounting seat 4 facing the pipe bending mold 5. A cover plate 9 is slidably installed in the annular groove. There are several through holes, and limit screws 12 are set in the through holes. The end of the limit screw 12 away from the cap head is fixed together with the card plate mounting seat 4 by means of a thread. The end of the limit screw 12 close to the cap head is nested with a return spring 11. One end of the return spring 11 is against the cover plate 9. The cover plate 9 can slide on the limit screw 12 under the action of an external force. At the same time, the return spring 11 can be used to drive the cover plate 9 to automatically return to its original position after the external force applied to the cover plate 9 disappears. The end of the cylinder tube 21 close to the pipe bending mold 5 is slidably installed with a piston spacer 24, and the cylinder piston 22 is connected to the The piston spacer 24 is installed in a sliding manner, and the piston spacer 24 is installed in conjunction with the cover plate 9. A pressure relief valve rod 10 is fixed on the cover plate 9 through a detachable connection. The other end of the pressure relief valve rod 10 is connected and fixed to the pressure relief valve inside the manual pressure relief valve 7. When the cylinder piston 22 reaches the end of the cylinder tube 21, the piston spacer 24 can be pushed to slide. When the piston spacer 24 slides, it can drive the cover plate 9 to move toward the end away from the manual pressure relief valve 7. The manual pressure relief valve 7 can be opened through the pressure relief valve rod 10 connected thereto to realize hydraulic backflow, thereby preventing the cylinder piston 22 from continuing to extend.

[0024] In this embodiment, a pressure relief handle is installed on the side wall of the manual pressure relief valve 7, and a pressure relief valve connected to the pressure relief handle is arranged inside the manual pressure relief valve 7. Two pressure relief valves connected to the pressure relief valve rod 10 and the pressure relief handle are arranged in parallel inside the manual pressure relief valve 7. The hydraulic oil reflux in the cylinder tube 21 can be controlled by the pressure relief valve rod 10 and the pressure relief handle.

[0025] In this embodiment, the limiting mechanism 6 includes a lower clamping plate 61 and an upper clamping plate 63. The lower clamping plate 61 is fixed to the bottom of the clamping plate mounting seat 4 by bolts. A connecting arm 62 is fixed to one side of the upper clamping plate 63. The end of the connecting arm 62 away from the upper clamping plate 63 is fixed to the clamping plate mounting seat 4 by a pin shaft, so that the upper clamping plate 63 can rotate. Two movable limiting parts 65 are installed between the lower clamping plate 61 and the upper clamping plate 63 through a detachable connection. The two movable limiting parts 65 are symmetrically arranged on both sides of the bending pipe mold 5. By rotating the upper clamping plate 63, the distance between the lower clamping plate 61 and the upper clamping plate 63 is increased, which facilitates the removal and placement of the movable limiting part 6, or the adjustment of the position of the movable limiting part 6.

[0026] In this embodiment, several groups of adjustment holes 64 for adjusting the installation position of the movable limit member 65 are formed on the lower clamping plate 61 and the upper clamping plate 63. The area of ​​the adjustment hole 64 is slightly larger than the cross-sectional area at both ends of the movable limit member 65, which enables the device to bend pipes of different lengths.

[0027] In this embodiment, a handle mounting base 1 is fixed to one end of the hydraulic cylinder 2 near the manual pressure relief valve 7, and a hydraulic motor, an oil storage tank and an auxiliary handle 3 are fixed on the handle mounting base 1. A switch button for controlling the operation of the hydraulic motor and a power supply cord are fixed on the auxiliary handle 3. The hydraulic motor and the oil storage tank are connected to the hydraulic cylinder 2 and the manual pressure relief valve 7 through an oil circuit. The auxiliary handle 3 facilitates hand-holding during use. The hydraulic motor can be directly installed on the pipe bending machine without the need for a separate hydraulic pump station. The overall size of the equipment is small and easy to carry and operate.

[0028] In this embodiment, universal rollers 8 are installed at the bottom of the handle mounting base 1 and below both ends of the lower clamping plate 61 through detachable connections to facilitate the movement of the device.

[0029] The working principle of the utility model is as follows: when in use, connect the power supply, adjust the position of the movable limiter 65 according to the curvature of the pipe bend, and then insert the pipe fitting to be processed between the pipe bending die 5 and the movable limiter 65, and control the extension of the hydraulic cylinder 2 by the switch button. The hydraulic cylinder 2 drives the pipe bending die 5 to move and bend the pipe fitting. When the cylinder piston 22 reaches the set extension length, it will push the piston spacer 24 to move, and the piston spacer 24 drives the cover plate 9 to move. When the cover plate 9 moves, it pulls the pressure relief valve rod 10 to move, thereby opening the internal of the manual pressure relief valve 7 One of the pressure relief valves allows the hydraulic oil flowing into the hydraulic cylinder 2 to flow back into the oil storage tank through the manual pressure relief valve 7, preventing the pipe bending mold 5 from continuing to move toward the limit mechanism 6 to complete the pipe bending work, and then moving the pressure relief handle on the manual pressure relief valve 7 to allow a large amount of hydraulic oil in the hydraulic cylinder 2 to flow back into the oil storage tank. Under the action of the tension spring 23, the cylinder piston 22 automatically retracts into the cylinder tube 21. At this time, the cover plate 9 returns to the clamping plate mounting seat 4 under the action of the return spring 11, and at the same time pushes the piston spacer 24 back to its original position to wait for the next pipe bending operation.

[0030] The circuit connection involved in the present invention is a common means used by those skilled in the art, and technical inspiration can be obtained through a limited number of experiments, and it belongs to the widely used existing technology.

[0031] Components not described in detail herein are prior art.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A handheld hydraulic pipe bender, comprising a hydraulic cylinder (2), wherein a manual pressure relief valve (7) connected to an internal oil circuit of the hydraulic cylinder (2) is fixed on a rear side wall of the hydraulic cylinder (2), the hydraulic cylinder (2) comprising a cylinder tube (21) and a cylinder piston (22) slidably mounted therein, a pipe bending die (5) being fixed to an outer end of the cylinder piston (22), the cylinder piston (22) being a hollow structure, and a tension spring being arranged inside the cylinder piston (22). (23), one end of the tension spring (23) is fixed to the end of the cylinder piston (22) near the bending mold (5), and the other end of the tension spring (23) is fixed to the end of the cylinder tube (21) away from the bending mold (5), and a clamping plate mounting seat (4) is fixed to the outside of the end of the cylinder tube (21) near the bending mold (5), and a limiting mechanism (6) for positioning the pipe fitting is installed on the side of the clamping plate mounting seat (4) facing the bending mold (5), characterized in that: The card plate mounting seat (4) is formed with an annular groove on one side facing the pipe bending mold (5), and a cover plate (9) is slidably mounted in the annular groove. The cover plate (9) is formed with a plurality of through holes, and a limit screw (12) is arranged in the through hole. The end of the limit screw (12) away from the cap head is fixed to the card plate mounting seat (4) by means of a thread. A return spring (11) is nested on the outside of the end of the limit screw (12) close to the cap head, and one end of the return spring (11) rests on the cover plate (9). The end of the oil cylinder tube (21) close to the pipe bending mold (5) is slidably mounted with a piston spacer (24), and the oil cylinder piston (22) is slidably mounted with the piston spacer (24). A pressure relief valve pull rod (10) is fixed to the cover plate (9) through a detachable connection, and the other end of the pressure relief valve pull rod (10) is connected and fixed to the pressure relief valve inside the manual pressure relief valve (7).

2. A handheld hydraulic pipe bender according to claim 1, characterized in that: A pressure relief handle is installed on the side wall of the manual pressure relief valve (7), and a pressure relief valve connected to the pressure relief handle is arranged inside the manual pressure relief valve (7). Two pressure relief valves connected to the pressure relief valve pull rod (10) and the pressure relief handle are arranged in parallel inside the manual pressure relief valve (7).

3. The handheld hydraulic pipe bender according to claim 1, characterized in that: The limiting mechanism (6) comprises a lower card plate (61) and an upper card plate (63), wherein the lower card plate (61) is fixed below the card plate mounting seat (4), and a connecting arm (62) is fixed on one side of the upper card plate (63), and an end of the connecting arm (62) away from the upper card plate (63) is fixed to the card plate mounting seat (4) by a pin shaft, and two movable limiting members (65) are installed between the lower card plate (61) and the upper card plate (63) through a detachable connection, and the two movable limiting members (65) are symmetrically arranged on both sides of the pipe bending mold (5).

4. A handheld hydraulic pipe bender according to claim 3, characterized in that: The lower clamping plate (61) and the upper clamping plate (63) are formed with a plurality of adjustment holes (64) for adjusting the installation position of the movable limiting member (65).

5. The handheld hydraulic pipe bender according to claim 3, characterized in that: A handle mounting base (1) is fixed to one end of the hydraulic cylinder (2) close to the manual pressure relief valve (7), and a hydraulic motor, an oil storage tank and an auxiliary handle (3) are fixed to the handle mounting base (1). A switch button for controlling the operation of the hydraulic motor and a power supply line are fixed to the auxiliary handle (3). The hydraulic motor and the oil storage tank are connected to the hydraulic cylinder (2) and the manual pressure relief valve (7) through an oil circuit.

6. The handheld hydraulic pipe bender according to claim 5, characterized in that: Universal rollers (8) are installed on the bottom of the handle mounting seat (1) and below both ends of the lower clamping plate (61) through detachable connections.

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