阅读说明：本技术 一种钳头及用于剪切施封锁的液压工具 (Binding clip and be used for shearing hydraulic means who executes blockade ) 是由 张银根 何挺伟 宁建忠 于 2019-03-18 设计创作，主要内容包括：本发明属于液压工具技术领域,特指一种钳头及用于剪切施封锁的液压工具,所述钳头包括左钳臂、右钳臂以及连接两者的连接板,所述左钳臂前端设置有左刀口,右钳臂前端设置有右刀口,所述左刀口上设置有平直刀刃,右刀口上设置有齿形刀刃,平直刀刃和齿形刀刃之前形成放置剪切物的剪切区域；所述左钳臂和右钳臂之间设置有拉簧,连接板通过固定销固定安装在左钳臂和右钳臂上；所述液压工具包括机身以及上述的钳头,所述机身上设置有连接段,钳头与连接段通过锁紧件可拆卸连接。本发明将钳头前端刀口处设置成一侧为平常的平直刀刃,另一侧为齿形刀刃,在对施封锁剪切时可避免剪切物弹出,增加安全性,且钳头在不使用时一直处于常开状态。(The invention belongs to the technical field of hydraulic tools, in particular to a binding clip and a hydraulic tool for shearing a sealing lock, wherein the binding clip comprises a left binding clip, a right binding clip and a connecting plate for connecting the left binding clip and the right binding clip; a tension spring is arranged between the left clamp arm and the right clamp arm, and the connecting plate is fixedly arranged on the left clamp arm and the right clamp arm through a fixing pin; the hydraulic tool comprises a machine body and the tong head, wherein the machine body is provided with a connecting section, and the tong head is detachably connected with the connecting section through a locking piece. According to the invention, the front end cutter opening of the binding clip is provided with the ordinary flat cutter edge on one side and the tooth-shaped cutter edge on the other side, so that the shearing object can be prevented from popping up when the sealing lock is sheared, the safety is improved, and the binding clip is always in a normally open state when not used.)

1. The utility model provides a binding clip, includes left tong arm (11), right tong arm (12) and connects connecting plate (13) between them, left tong arm (11) front end is provided with left edge of a knife, and right tong arm (12) front end is provided with right edge of a knife, its characterized in that: a flat cutting edge (14) is arranged on the left cutting edge, a tooth-shaped cutting edge (15) is arranged on the right cutting edge, and a shearing area for placing a sheared object is formed in front of the flat cutting edge (14) and the tooth-shaped cutting edge (15); a tension spring (16) is arranged between the left clamp arm (11) and the right clamp arm (12), and the connecting plate (13) is fixedly arranged on the left clamp arm (11) and the right clamp arm (12) through a fixing pin (17).

2. The binding clip of claim 1, wherein: the straight blade (14) is a straight sharp blade, the tooth-shaped blade (15) is a tooth-shaped blunt blade, and the middle part of the tooth-shaped blade (15) is provided with a straight groove (151).

3. The binding clip of claim 1, wherein: the middle parts of the left forceps arm (11) and the right forceps arm (12) are respectively provided with a left elastic cylindrical pin (181) and a right elastic cylindrical pin (182), two ends of the tension spring (16) are respectively hooked on the left elastic cylindrical pin (181) and the right elastic cylindrical pin (182), and the distance from the left elastic cylindrical pin (181) to the side edge of the left forceps arm (11) is equal to the distance from the right elastic cylindrical pin (182) to the side edge of the right forceps arm (12).

4. The binding clip of claim 1 or 2, wherein: mounting grooves (191) are formed in the opposite surfaces of the left clamp arm (11) and the right clamp arm (12), the two mounting grooves (191) are combined to form a mounting cavity, and a steel ball (19) is arranged in the mounting cavity.

5. A hydraulic tool for shear lock out, characterized by: the binding clip comprises a body (2) and the binding clip according to any one of claims 1 to 4, wherein a connecting section (21) is arranged on the body (2), a through hole (22) is formed in the connecting section (21), a third connecting hole (131) is formed below the connecting plate (13), and the third connecting hole (131) is detachably connected with the through hole (22) through a locking piece; the clamp is characterized in that a propelling assembly for driving the clamp head to work is arranged in the connecting section (21), and a motor assembly and an oil circuit system for driving the propelling assembly to work are arranged in the machine body (2).

6. The hydraulic tool for shear lock out of claim 5, wherein: the locking piece comprises a connecting shaft (31), one end of the connecting shaft (31) penetrates through the through hole (22) and the third connecting hole (131), the other end of the connecting shaft is connected with a locking handle (32), a mounting hole (23) is formed in the connecting section (21), a resetting piece (33) and a locking pin (34) are arranged in the mounting hole (23), an opening in the upper end of the mounting hole (23) is formed in the through hole (22), and a locking groove (35) matched with the locking pin (34) is formed in the connecting shaft (31); the locking groove (35) comprises a radial groove (352) and an axial groove (351) which are communicated with each other.

7. The hydraulic tool for shear lock application according to claim 5 or 6, wherein: the propelling assembly comprises a roller (41) and a roller seat (42), a cylinder body (5) is arranged in the machine body (2), one side of the cylinder body (5) is connected with an oil bag (6), an oil inlet valve (7) is arranged at the joint of the cylinder body (5) and the oil bag (6), a first installation cavity (51) is formed in the other side of the cylinder body (5), a piston (43) is arranged in the first installation cavity (51), the front end of the piston (43) is connected with the roller seat (42), an oil outlet valve (9) is arranged between the rear end of the piston (43) and the cylinder body (5), a plurality of oil ducts are formed in the cylinder body (5), and a pressure release valve (8) is arranged in the cylinder body (5), wherein the oil bag (6), the oil inlet valve (7), the oil ducts, the oil outlet valve (9.

8. The hydraulic tool for shear lock out of claim 7, wherein: the oil passage comprises an oil inlet passage (52), an oil outlet passage (53) and an oil return passage (54), an oil cavity (55) is formed in the cylinder body (5), one end of the oil inlet passage (52) is communicated with the oil bag (6) and is provided with the oil inlet valve, and the other end of the oil inlet passage is communicated with the oil cavity (55); one end of the oil outlet channel (53) is communicated with an oil cavity (55), and the other end of the oil outlet channel is communicated with the first mounting cavity (51) and is provided with the oil outlet valve; one end of the oil return channel (54) is communicated with the oil cavity (55), and the other end of the oil return channel is communicated with the oil bag (6) and provided with the pressure release valve.

9. The hydraulic tool for shear lock out of claim 8, wherein: the oil chamber (55) is internally provided with a guide post (56), the periphery of the guide post (56) is sleeved with a guide spring (57), the inner side of the motor component is connected with a push rod (58), and the inner end of the push rod (58) is abutted to the guide post (56).

10. The hydraulic tool for shear lock out of claim 8, wherein: relief valve (8) are including pressure release disk seat (81), needle (82), spring holder (86), pressure release spring (87) and pressure release piston (83), and the end is stifled in pressure release disk seat (81) oil return channel (54) oil outlet department, seted up passageway (84) in pressure release disk seat (81), and needle (82) inner needle point supports the exit at passageway (84), and pressure release piston (83) cover is established in needle (82) inner and is offered oil outlet (88) that the confession fluid passes through, and pressure release spring (87) are installed and are located needle (82) periphery between pressure release piston (83) and spring holder (86) and overlap, and needle (82) outer end extends spring holder (86) and cylinder body (5) are connected with pressure release pole (85).

Technical Field

The invention belongs to the technical field of hydraulic tools, and particularly relates to a binding clip and a hydraulic tool for shearing a sealing lock.

Background

The container can be provided with sealing locks (lead seals) for theft prevention in the process of factory transportation, each sealing lock is disposable, and the container cannot be used after being cut. Some large containers use relatively strong and bulky sealing locks, which are typically made of plastic-clad metal, requiring special tools to shear the lock.

The tools for shearing the sealing lock mainly comprise two types: the manual shears are hard and are not widely used. The existing hydraulic shears generally comprise a binding clip positioned at the front end and a hydraulic machine body for driving the binding clip to work, wherein a cutting edge is arranged at the front end of the binding clip, an area for placing a sealing lock is formed between a left cutting edge and a right cutting edge, the two sides of the cutting edge are sharp blades, and the driving force of the electric hydraulic machine body is generally larger, so that the sealing lock can be rapidly cut off in the process of cutting the sealing lock, the cut sealing lock can be directly flicked off due to the overlarge driving force and even flicked to the body of an operator, and when the force is larger, potential safety hazards are easily caused to the operator; meanwhile, the existing binding clip is generally designed in a normally closed state, and when the binding clip is used, the binding clip is opened firstly and then extends into a sealing lock, so that time and labor are consumed.

Disclosure of Invention

The present invention is to solve the above problems in the prior art, and an object of the present invention is to provide a tong head and a hydraulic tool for shearing a sealing lock, wherein the tong head can be kept in a normally open state, and can prevent the two ends of the sealing lock from popping up respectively at the moment of fracture due to excessive force application during shearing.

The purpose of the invention is realized as follows:

a binding clip comprises a left binding clip, a right binding clip and a connecting plate for connecting the left binding clip and the right binding clip, wherein a left knife edge is arranged at the front end of the left binding clip, a right knife edge is arranged at the front end of the right binding clip, a straight knife edge is arranged on the left knife edge, a tooth-shaped knife edge is arranged on the right knife edge, and a shearing area for placing a shearing object is formed in front of the straight knife edge and the tooth-shaped knife edge; and a tension spring is arranged between the left clamp arm and the right clamp arm, and the connecting plate is fixedly arranged on the left clamp arm and the right clamp arm through a fixing pin.

The straight blade is a straight sharp blade, the tooth-shaped blade is a tooth-shaped blunt blade, and the middle part of the tooth-shaped blade is provided with a straight groove.

The left clamp arm and the right clamp arm are respectively provided with a left elastic cylindrical pin and a right elastic cylindrical pin at the middle parts, two ends of the tension spring are respectively hooked on the left elastic cylindrical pin and the right elastic cylindrical pin, and the distance from the left elastic cylindrical pin to the side edge of the left clamp arm is equal to the distance from the right elastic cylindrical pin to the side edge of the right clamp arm.

Further, mounting grooves are formed in opposite faces of the left clamp arm and the right clamp arm, the two mounting grooves are combined to form a mounting cavity, a steel ball is arranged in the mounting cavity, and the steel ball is located on the front side of the tension spring.

A hydraulic tool for shearing a sealing lock comprises a machine body and the tong head, wherein a connecting section is arranged on the machine body, a through hole is formed in the connecting section, a third connecting hole is formed below the connecting plate, and the third connecting hole is detachably connected with the through hole through a locking piece; the connecting section is internally provided with a propelling assembly for driving the binding clip to work, and the machine body is internally provided with a motor assembly and an oil circuit system.

Further set up as, the retaining member includes the connecting axle, and connecting axle one end is passed perforating hole and third connecting hole, and the other end is connected with the locking handle, set up the mounting hole in the linkage segment, be equipped with the piece that resets and lockpin in the mounting hole, the opening is seted up on the mounting hole in the perforating hole, set up the locked groove of mutually supporting with the lockpin on the connecting axle.

It is further provided that the locking groove comprises a radial groove and an axial groove which are in communication with each other.

Further set up to, the propulsion subassembly includes wheel train and gyro wheel seat, be provided with the cylinder body in the fuselage, cylinder body one side is connected with the oil bag, and the cylinder body is provided with the inlet valve with the oil bag junction, and first installation cavity has been seted up to the cylinder body opposite side, is provided with the piston in the first installation cavity, and the piston front end is connected the gyro wheel seat is provided with the outlet valve between piston rear end and the cylinder body, has seted up a plurality of oil ducts in the cylinder body and is provided with the relief valve, inlet valve, oil duct, relief valve and outlet valve constitute oil piping system.

The oil duct further comprises an oil inlet channel, an oil outlet channel and an oil return channel, an oil cavity is formed in the cylinder body, one end of the oil inlet channel is communicated with the oil bag and provided with the oil inlet valve, and the other end of the oil inlet channel is communicated with the oil cavity; one end of the oil outlet channel is communicated with the oil cavity, and the other end of the oil outlet channel is communicated with the first mounting cavity and is provided with the oil outlet valve; one end of the oil return channel is communicated with the oil cavity, and the other end of the oil return channel is communicated with the oil bag and provided with the pressure release valve.

Further, a guide post is installed in the oil cavity, a guide spring is sleeved on the periphery of the guide post, an ejector rod is connected to the inner side of the motor assembly, and the inner end of the ejector rod is abutted to the guide post.

Further set up to, the relief valve includes pressure release disk seat, needle, spring holder, pressure release spring and pressure release piston, and the inner end of pressure release disk seat is stifled to be in oil return passageway oil outlet department has seted up the passageway in the relief valve seat, and the needle point of needle inner supports in the exit of passageway, and the pressure release piston cover is established at needle inner and is offered the oil outlet way that fuel feeding liquid passes through, and pressure release spring installs and overlaps between pressure release piston and spring holder and locate the needle periphery, and the needle outer end extends spring holder and cylinder body are connected with the pressure release pole.

Compared with the prior art, the invention has the outstanding and beneficial technical effects that:

according to the invention, the front end cutter opening of the binding clip is arranged to be a common flat cutter on one side and a tooth-shaped cutter on the other side, when the hydraulic tool is started to drive the opening of the binding clip to be closed, a shearing object (sealing lock) is clamped between the flat cutter and the tooth-shaped cutter and gradually breaks under the clamping impact of the two cutters, and because the contact mode between the tooth-shaped cutter and the shearing object is different from the contact mode between the flat cutter and the shearing object, the side, in contact with the flat cutter, of the shearing object is more quickly broken, the speed of breaking the two sides is driven to form a speed difference, the shearing object is prevented from popping up when being cut finally, and the safety is improved.

Drawings

Fig. 1 is a schematic structural view of the binding clip of the present invention.

Figure 2 is one of the cross-sectional views of the binding clip of the present invention.

Fig. 3 is a second cross-sectional view of the binding clip of the present invention.

Figure 4 is a third cross-sectional view of the binding clip of the present invention.

Fig. 5 is a partially enlarged view of fig. 3 at a.

Fig. 6 is a reference diagram showing the use state of the hydraulic tool of the present invention.

FIG. 7 is a reference view showing the attaching section and the locker-mounting structure according to the present invention.

FIG. 8 is a schematic view of the structure of the retaining member of the present invention.

Fig. 9 is a cross-sectional view of the fuselage of the present invention.

Fig. 10 is a partially enlarged view of fig. 9 at B.

Fig. 11 is a cross-sectional view of an oil chamber structure of the present invention.

Fig. 12 is a sectional view of the relief valve mounting structure of the present invention.

Detailed Description

The invention will be further described in the following with reference to specific embodiments thereof, with reference to figures 1-12,

as shown in fig. 1-5, a binding clip is provided, which comprises a left tong arm 11, a right tong arm 12 and a connecting plate 13 connecting the left tong arm and the right tong arm, wherein a left knife edge is arranged at the front end of the left tong arm 11, a right knife edge is arranged at the front end of the right tong arm 12, a straight knife edge 14 is arranged on the left knife edge, a tooth-shaped knife edge 15 is arranged on the right knife edge, and a cutting area for placing a cut object is formed in front of the straight knife edge 14 and the tooth-shaped knife edge 15; a tension spring 16 is arranged between the left clamp arm 11 and the right clamp 12, and the connecting plate 13 is fixedly arranged on the left clamp arm 11 and the right clamp arm 12 through a fixing pin 17. First connecting hole and second connecting hole have been seted up respectively to the left and right sides of connecting plate, left side tong arm and right tong arm have been seted up left through-hole and right through-hole correspondingly, and two fixed pins pass first connecting hole and left through-hole, second connecting hole and right through-hole respectively and link to each other connecting plate and left tong arm, right tong arm, in order to prevent the removal of fixed pin 17, specially block on fixed pin 17 and be equipped with circlip 171, circlip 171 laminates in the lateral surface of connecting plate 13.

The straight cutting edge 14 is sharp, and for straight sharp cutting edge, profile of tooth cutting edge 15 is dull, for profile of tooth dull cutting edge, profile of tooth cutting edge 15 middle part seted up one with straight cutting edge 14 straight flute 151 of mutually supporting when straight cutting edge 14 and profile of tooth cutting edge 15 are driven under the external force and are closed gradually for this straight flute 151 can be gone into to straight cutting edge 14 front end, avoids producing between straight cutting edge 14 and the profile of tooth cutting edge 15 and interferes. The straight blade is sharper than the tooth-shaped blade, so that the side of the cut object contacting with the straight blade is more quickly cut off, the speed of the two-side breakage is promoted to form a speed difference, the cut object is prevented from popping up when being cut off finally, and the safety is improved.

As shown in fig. 2, holes are respectively formed in the middle portions of the left caliper arm 11 and the right caliper arm 12, the two holes are combined to form an area for accommodating the tension spring 16, a left elastic cylindrical pin 181 and a right elastic cylindrical pin 182 are arranged at two ends of each hole, two ends of the tension spring 16 are respectively hooked on the left elastic cylindrical pin 181 and the right elastic cylindrical pin 182, and the distance from the left elastic cylindrical pin 181 to the side edge of the left caliper arm 11 is equal to the distance from the right elastic cylindrical pin 182 to the side edge of the right caliper arm 12. The tension spring is arranged to help the front ends of the left clamp arm and the right clamp arm to always keep a normally open state under the condition of no external force, and the use is convenient.

Mounting grooves 191 are formed in the opposite surfaces of the left clamp arm 11 and the right clamp arm 12, the two mounting grooves 191 are combined to form a mounting cavity, a steel ball 19 is arranged in the mounting cavity, and the steel ball 19 is located on the front side of the tension spring 16. The arrangement of the steel ball can prevent the left clamp arm and the right clamp arm from being staggered in the closing process, and the accuracy of the structure is enhanced.

As shown in fig. 6, a hydraulic tool for shearing sealing lock is provided, which includes a machine body 2 and the above binding clip, wherein the machine body 2 is provided with a connecting section 21, an opening 210 is arranged in the middle of the connecting section 21, the binding clip is detachably mounted in the opening 210, two through holes 22 are formed in the connecting section 21, a third connecting hole 131 is formed below the connecting plate 13, and the third connecting hole 131 and the through holes 22 are detachably connected through a locking member. The specific connection structure is as follows: the retaining member includes connecting axle 31, and connecting axle 31 one end is passed perforating hole 22 and third connecting hole 131, and the other end is connected with locking handle 32, set up mounting hole 23 in the linkage segment 21, be equipped with in the mounting hole 23 and reset piece 33 and lockpin 34, reset piece 33 chooses for use the spring, and the opening is seted up in mounting hole 23 upper end in perforating hole 22, set up the locked groove 35 with lockpin 34 mutually supporting on the connecting axle 31. The locking groove 35 includes a radial groove 352 and an axial groove 351 (shown in fig. 8) that communicate with each other.

When the binding clip is installed, the locking member is taken out, then the binding clip is clamped into the opening 210, the third connecting hole 131 is aligned with the through hole 22, at this time, the lock pin 34 is ejected out due to the action of the spring, the upper end of the lock pin 34 protrudes and is positioned in the through hole, the connecting shaft is rotated to the direction of the notch of the axial groove 351 and is inserted towards the lock pin 34, when one end of the connecting shaft 31 is clamped into the through hole positioned at the outer side, the upper end of the lock pin 24 is just positioned in the radial groove 352 (as shown in fig. 7), in order to prevent the locking member from slipping out in the working process, the locking handle 32 can be rotated to enable the notch of the axial groove 351 to face the direction except for the lock pin 34, at this time, the upper end of the lock pin 34 can be stably abutted against the axial groove 351, the connecting shaft can not be axially moved, when the locking handle is facing downward, i.e. the notch representing the axial slot 351 is facing upward, as shown in fig. 7, the notch is facing away from the locking pin 34; conversely, when the locking handle is facing upwards, i.e. the notch representing the axial groove 351 is facing downwards, the notch is facing towards the locking pin 34). When the binding clip is disassembled, the locking handle 32 is firstly rotated, so that the connecting shaft 351 faces the direction of the lock pin 34 towards the groove opening of the groove, the locking handle 32 can be pulled, the connecting shaft is taken out, then the binding clip is taken down, and the binding clip is very convenient.

The connecting section 21 is internally provided with a propelling component for driving the binding clip to work, the propelling component comprises two rollers 41 and two roller seats 42, the two rollers 41 are arranged in parallel, the two rollers 41 are hinged on the roller seats 42 and respectively correspond to the inner sides of the rear ends of the left tong arm 11 and the right tong arm 12, when the propelling component is pushed forwards, the rear ends of the left tong arm 11 and the right tong arm 12 can be pushed outwards, and due to the effect of the connecting plate 13, when the rear ends of the left tong arm and the right tong arm are pushed outwards, the front ends are gradually closed, so that the purpose of shearing and sealing is achieved.

Be provided with cylinder body 5 in the fuselage 2, 5 one sides of cylinder body are connected with oil bag 6, and cylinder body 5 is provided with inlet valve 7 with 6 junctions of oil bag, and first installation cavity 51 has been seted up to 5 opposite sides of cylinder body, is provided with piston 43 in the first installation cavity 51, and the pin joint is passed through to piston 43 front end the roller seat 42 is provided with out oil valve 9 between piston 43 rear end and the cylinder body 5, and piston 43 periphery is provided with reset spring 431, has still seted up a plurality of oil ducts in the cylinder body 5 and has been provided with relief valve 8, inlet valve 7, oil duct, relief valve 8 and out oil valve 9 constitute oil piping system.

The oil passage comprises an oil inlet passage 52, an oil outlet passage 53 and an oil return passage 54, an oil cavity 55 is formed in the cylinder body 5, one end of the oil inlet passage 52 is communicated with the oil bag 6 and is provided with the oil inlet valve 7, and the other end of the oil inlet passage is communicated with the oil cavity 55; one end of the oil outlet channel 53 is communicated with an oil cavity 55, and the other end of the oil outlet channel is communicated with the first mounting cavity 51 and is provided with the oil outlet valve 9; one end of the oil return channel 54 is communicated with the oil chamber 55, and the other end is communicated with the oil bag 6 and provided with the pressure release valve 8.

As shown in fig. 9-10, the oil inlet valve 7 is an oil inlet check valve, and includes an oil inlet valve seat 71, a valve cap 75 is disposed at the front end of the oil inlet valve seat 71, a through hole 72 is formed in the valve cap 75 and can allow oil to pass through, a valve core 73 is disposed in the valve seat 71, the rear end of the valve core 73 can be blocked at the outer end of the through hole 72, a spring 74 is disposed between the front end of the valve core 73 and the valve cap 75, a filter body 61 is disposed at the rear side of the valve seat 71, the outer end of the filter body 61 extends into the oil bag 6, a filter 62 is disposed in the filter body 61, a filter screen is mounted.

The working principle of the oil inlet valve is as follows: when the pressure in the oil inlet passage 52 is lower than the pressure in the oil bag 6, the oil in the oil bag 6 enters the valve seat 71 through the filter body 61, the valve element 73 is pushed, the through hole 72 is opened, and the oil flows to the oil inlet passage 52 through the through hole 72 to finish oil inlet; when the pressure in the oil inlet passage 52 is higher than the pressure in the oil bag, the valve core blocks the outer end of the through hole 72 under the pushing of the oil and the elastic force of the spring 74, and the oil bag 6 is isolated from the oil inlet passage 52.

The oil outlet valve 9 is an oil outlet one-way valve, the structure of the oil outlet one-way valve is the same as that of the oil inlet one-way valve, oil in the oil inlet channel 52 enters the oil outlet channel 53 through the oil cavity 55, the oil pushes the valve core to open the through hole in the valve cap and flows into the first mounting cavity 51, so that the piston 43 is pushed, the piston 43 drives the pushing assembly to move forwards, and the tong heads are enabled to be closed.

As shown in fig. 10-11, a guide post 56 is installed in the oil chamber 55, a guide spring 57 is sleeved on the outer periphery of the guide post 56, one end of the guide spring 57 abuts against the inner wall of the oil chamber 55, the other end of the guide spring is provided with a spring seat 59, one side of the spring seat 59 is blocked at an oil inlet of the oil outlet channel 53, a hole is formed in the middle of the spring seat 59, and one end of the guide post is blocked in the hole; the machine body 2 is internally provided with a motor assembly 24, the inner side of the motor assembly 24 is connected with a push rod 58, and the inner end of the push rod 58 is abutted against the guide column 56. When the motor assembly is started, the push rod 58 is pushed inwards, so that the guide post 56 is pushed inwards, the spring seat 59 moves inwards along with the guide post, the pressure in the oil cavity 55 is gradually reduced, the oil inlet check valve 7 starts to work for oil inlet, the oil outlet channel 53 is gradually opened by the spring seat 57 in the moving process, oil can enter the first mounting cavity by opening the oil outlet valve 9 through the oil outlet channel 53, the piston 43 is further pushed, the piston 43 drives the pushing assembly to move forwards, and the tong head is further closed.

As shown in fig. 12, the relief valve 8 is a pressure relief check valve, including pressure relief valve seat 81, needle 82, spring seat 86, pressure relief spring 87 and pressure relief piston 83, the end block is in pressure relief valve seat 81 oil return channel 54 oil outlet department has seted up passageway 84 in the pressure relief valve seat 81, and the needle point supports in the exit of passageway 84 in the inner needle 82, and pressure relief piston 83 cover establishes in needle 82 the inner and has seted up the oil outlet channel 88 that supplies fluid to pass through, and the oil return opening has been seted up in cylinder body and the oil bag junction, pressure relief piston 83 side block is in oil return opening department, and pressure relief piston 83 is at the removal in-process, and the export of oil outlet channel 88 can pass through the oil return opening, and when export and oil return opening intercommunication. The pressure relief spring 87 is installed between the pressure relief piston 83 and the spring seat 86 and is sleeved on the periphery of the valve needle 82, and the outer end of the valve needle 82 extends out of the spring seat 86 and the cylinder 5 to be connected with the pressure relief rod 85. The oil outlet channel 88 is arranged in the hydraulic piston 83, so that the oil return port is opened when the hydraulic piston 83 moves together with the valve needle 82, and oil directly flows through the oil outlet channel 88 into the oil bag 6 after passing through the channel 84, which is very quick and convenient.

The working principle of the pressure release valve is as follows: the pressure relief rod 85 is pulled to drive the valve needle 82 and the pressure relief piston 83 to move outwards, the needle tip of the valve needle 82 leaves the channel 84, and oil in the oil return channel 54 flows through the channel 84 and the oil outlet channel 88 and finally flows into the oil bag 6 to complete pressure relief and oil return.

The working principle of the invention is as follows:

the tong head is arranged on the machine body, the opening at the front end of the tong head faces the sealing lock 10, the sealing lock 10 is positioned between the straight blade 14 and the tooth-shaped blade 15, the motor assembly is controlled to start, the ejector rod 58 moves inwards, the guide column 56 is pushed inwards, at the moment, the pressure in the oil cavity 55 is reduced, as the pressure in the oil bag 6 is greater than the pressure in the oil cavity 55, oil enters the oil inlet valve and opens the oil inlet valve, flows into the oil cavity 55 through the oil inlet channel 52, enters the oil outlet valve from the oil outlet channel 53 and pushes the oil outlet valve to enter the first mounting cavity 51, the piston 43 is pushed to move forwards, and the pushing assembly is driven to apply force to the left tong arm and the right tong arm, so that the shearing process is.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.