Mechanical arm assembly for automatic production
Technical Field
The invention relates to the field of automation, in particular to a mechanical arm assembly for automatic production.
Background
The arm is that the arm of a replacement people carries out the machinery of processing, and can carry on the singlechip and use, realize automated control, orderly completion processing operation, the centre gripping of the product of processing is treated in the completion, operations such as transport and spot welding, for the manual work, arm work efficiency is high, can bear great working strength, and the error of during operation appearance is less, completion that can be accurate and quick is to the processing of product, be one of the important machinery of present replacement manual work, current arm mostly has better work effect, but also there is certain weak point to remain to be improved, believe can obtain further development.
Although the existing mechanical arm assembly for automatic production has a good use effect, certain defects exist when the mechanical arm assembly is used, the traditional mechanical arm assembly is fixed, the position cannot be adjusted in the horizontal direction, the use range of the mechanical arm is limited, the adjustment in the horizontal direction cannot be performed for different use environments, the connecting means of a support arm and an arm rod of the existing mechanical arm assembly is simple, the loosening condition easily occurs when the support arm and the arm rod are used for a long time, when the arm end joint of the mechanical arm is stressed greatly, other joints cannot be shared by the arm end joint well, the condition that the arm end joint is stressed too much for a long time and is damaged easily occurs is caused, the service life of the arm end joint is short, and certain influence is caused on the use of the mechanical arm assembly to a certain extent.
Disclosure of Invention
The invention aims to provide a mechanical arm assembly for automatic production, which can solve the problems that the position of the traditional mechanical arm assembly cannot be adjusted in the horizontal direction after the traditional mechanical arm assembly is fixed, so that the use range of a mechanical arm is limited, the adjustment in the horizontal direction cannot be carried out aiming at different use environments, the connecting means of a support arm and an arm rod of the traditional mechanical arm assembly is simpler, the support arm and the arm rod are easy to loosen when used for a long time, when the arm end joint of the mechanical arm is stressed greatly, other joints cannot share the arm end joint well, so that the arm end joint is easy to damage when stressed excessively for a long time, so that the service life of the arm end joint is shorter, and can effectually reduce the pressure that the arm end joint bore when arm end joint centre gripping article, play better guard action, can also consolidate support arm and armed lever for firm degree between support arm and the armed lever is better, has effectually avoided appearing not hard up condition between support arm and the armed lever.
The purpose of the invention can be realized by the following technical scheme:
an automatic mechanical arm assembly for production comprises a base plate, wherein a box body is fixedly mounted on the upper surface of the base plate, a translation frame is fixedly mounted on the lower surface of the base plate, a fixed disc is arranged on the upper surface of the box body, a driving disc is connected to the upper surface of the fixed disc, a short arm is connected to the upper portion of the driving disc, a support arm is connected to the inner side of the short arm, a connecting arm is arranged on one side of the support arm, a support seat is mounted at the upper end of the support arm, a rotary joint is connected to the upper portion of the support seat, an arm rod is connected to one side of the rotary joint, one end of the arm rod is connected with an arm end joint, and a pressure reduction support is arranged outside the arm end joint;
a power supply box and a first motor are arranged on one side face of the box body, the power supply box and the first motor are arranged in parallel, a gear rod is connected to one side of the first motor, a sealing seat is connected to one end of the gear rod, and a driven gear is arranged inside the box body;
the lower surface of the support is provided with clamping plates at two sides, the lower surface of the support is provided with a fixed shaft at the rear part, the upper surface of the support is provided with a first conjunction block and two groups of second conjunction blocks, and the two groups of second conjunction blocks are positioned at two sides of the first conjunction block;
a second motor is arranged on one side of the rotary joint, a first fit groove and a second fit groove are formed in the lower surface of the rotary joint, a fastening block is arranged on one side of the rotary joint close to the bottom, a compression cylinder is arranged at the upper end inside the fastening block, a movable block is arranged at the lower end inside the fastening block, a top block is arranged inside the movable block, a cushion block is arranged at the lower end of the movable block, and a clamping seat is embedded in the upper end inside the cushion block;
the pressure reducing support comprises two groups of transverse supporting rods, a movable rotating shaft is arranged between the front surface and the rear surface of each transverse supporting rod in a penetrating mode, the upper surface of each transverse supporting rod is connected with an upper fixing frame, and the lower surface of each transverse supporting rod is connected with a lower fixing frame;
the translation frame includes first transverse bar and second transverse bar, the outside of first transverse bar and second transverse bar all install with the extension plate, be connected with two sets of connecting rods between first transverse bar and the second transverse bar, it is two sets of connecting rod parallel arrangement, the inboard embedding of first transverse bar and second transverse bar is provided with the translation slide rail, and is two sets of be connected with two sets of anchor strut between the connecting rod, it is two sets of anchor strut parallel arrangement.
Preferably, the total length of the translation frame is equal to the length of the bottom plate, the upper surfaces of the first transverse rod and the second transverse rod on the translation frame are connected with the lower surface of the bottom plate in a welded mode, the upper surface of the translation slide rail is connected with the first transverse rod and the second transverse rod in a sliding mode, and the upper surface of the translation slide rail is connected with the lower surface of the bottom plate in a welded mode.
Preferably, the center of the inside of the fixed disc is clamped with a turntable, and the upper part of the turntable is connected with the lower part of the driving disc.
Preferably, the side of the sealing seat is circularly arranged, and one side of the sealing seat is clamped inside one side of the box body.
Preferably, the first fitting groove and the second fitting groove are fitted with the first fitting block and the second fitting block, and the width of the first fitting block is three times that of the second fitting block.
Preferably, one end of the connecting arm is movably connected with the inner surface of the fixed shaft, and the inclination of the connecting arm is the same as that of the supporting arm.
Preferably, the length of support arm is greater than the length of armed lever, and the armed lever is cylindricly setting, the rear surface of horizontal branch links up with the one end surface of armed lever mutually.
Preferably, the width of extension plate is less than the width of first transverse bar and second transverse bar, and runs through the upper and lower surface of extension plate and has seted up a plurality of groups installation screw, and a plurality of groups installation screw are horizontal word equidistance and arrange.
Preferably, a plurality of groups of oblique gears are arranged on the periphery of the gear rod, and the oblique gears are matched with peripheral gears of the driven gears.
Preferably, the use steps of the mechanical arm assembly are as follows:
the method comprises the following steps: firstly, fixing a bottom plate on a contact surface through an extension plate, externally connecting a fixing screw to an installation screw hole on the extension plate, fixing the extension plate and the contact surface, and fixing the whole mechanical arm assembly after the extension plate is fixed;
step two: the translation sliding rail slides in the first transverse rod and the second transverse rod to drive the bottom plate to perform horizontal position deviation, the bottom plate drives the box body on the upper portion of the bottom plate to complete position adjustment in the horizontal direction, and the horizontal position adjustment of the whole mechanical arm is completed;
step three: the first conjunction groove and the second conjunction groove are in conjunction with the first conjunction block and the second conjunction block, the top block is pushed into the clamping seat through the compression cylinder, and the movable block is further pushed out to enable the cushion block to be in contact with the supporting seat, so that the connection of the supporting arm and the arm rod is completed;
step four: start first motor, first motor drives the gear lever and rotates, gear revolve on the gear lever drives driven gear and rotates, driven gear passes through the rotation that the carousel drove the driving-disc, the rotation from the driving-disc drives the rotation on the short arm horizontal direction, drive support arm and armed lever through the short arm and rotate, accomplish the position change and the operation of the horizontal direction of robotic arm subassembly, at the short arm, support arm and armed lever link up the external other motors of department, drive the buckling of support arm and armed lever through the motor, accomplish the adjustment of the gradient of vertical direction support arm and armed lever.
The invention has the beneficial effects that:
according to the invention, the translation frame is arranged on the lower surface of the bottom plate, when the mechanical arm assembly needs to be adjusted in the horizontal direction after being fixed, the translation frame is pushed, the translation sliding rail slides in the first transverse rod and the second transverse rod to drive the bottom plate to shift the position in the horizontal direction, the bottom plate drives the box body on the upper part of the bottom plate to complete position adjustment in the horizontal direction, and the position adjustment in the horizontal direction of the whole mechanical arm is completed, so that the adjustment in the horizontal direction of the mechanical arm assembly can be realized after the mechanical arm assembly is fixed, the mechanical arm assembly can be adjusted according to specific use conditions, and the problem that the traditional mechanical arm assembly is inconvenient to adjust in the horizontal direction after being installed and fixed is solved;
the first conjunction groove and the second conjunction groove are arranged at the joint of the support and the rotary joint and are matched with the first conjunction block and the second conjunction block, the fastening block is matched, after the first conjunction groove and the second conjunction groove are matched with the first conjunction block and the second conjunction block, the fastening block is adjusted to be in a fastening state, the jacking block is jacked into the clamping seat through the compression cylinder, the movable block is further jacked out to enable the cushion block to be in contact with the support, the cushion block is in contact with the upper surface of the support to play a buffering role, after the cushion block is in contact with the support, the movable block is in a jacking state, so that the connection of the support arm and the arm rod is completed, and the fastening block is matched through the conjunction grooves and the conjunction blocks, so that the support and the rotary joint have good firmness during connection, the connection effect of the support arm and the arm rod is good, the stability is good during work, and the situation of loosening and falling is not easy to occur;
through the periphery at arm end joint set up the decompression support, the decompression support is through the laminating of two sets of horizontal branch at rotary joint's both sides face, go up fixed frame and lower fixed frame respectively with rotary joint's upper and lower surface laminating, thereby accomplish with rotary joint surperficial fixed, the existence of activity pivot makes two sets of horizontal branch can carry out slight adjustment, satisfy the fine setting demand, when arm end joint atress, the one end and the rotary joint of two sets of horizontal branch are laminated mutually, through the holistic conduction of decompression support, play the decompression effect, thereby protect arm end joint, make arm end joint atress can evenly atress, life when having improved arm end joint atress.
Drawings
In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.
Fig. 1 is a schematic view of the overall structure of the present invention.
Fig. 2 is a structural view of the case of the present invention.
FIG. 3 is a sectional view of the container body according to the present invention.
Fig. 4 is a structural view of the cradle of the present invention.
Fig. 5 is a structural view of a rotary joint of the present invention.
Figure 6 is a cross-sectional view of a fastening block of the present invention.
FIG. 7 is a structural view of a pressure reducing mount of the present invention.
Fig. 8 is a bottom view of the pan carriage of the present invention.
In the figure: 1. a base plate; 2. a box body; 3. a translation frame; 4. fixing the disc; 5. a drive disc; 6. a short arm; 7. A support arm; 8. a connecting arm; 9. a support; 10. a rotary joint; 11. an arm lever; 12. an arm end joint; 13. a reduced-pressure scaffold; 14. a first motor; 15. a power supply box; 16. a gear lever; 17. a sealing seat; 18. a driven gear; 19. a chuck; 20. a fixed shaft; 21. a first engagement block; 22. a second engagement block; 23. a second motor; 24. a first engagement groove; 25. a second engagement groove; 26. a fastening block; 27. a compression cylinder; 28. a movable block; 29. a top block; 30. a card holder; 31. cushion blocks; 32. a transverse strut; 33. a movable rotating shaft; 34. an upper fixing frame; 35. a lower fixed frame; 36. a first transverse bar; 37. a second transverse bar; 38. an extension plate; 39. A connecting rod; 40. translating the slide rail; 41. and a reinforcing rod.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-8, a robot arm assembly for automated manufacturing, includes a base plate 1, a box 2 fixedly mounted on the upper surface of the base plate 1, a translation frame 3 fixedly mounted on the lower surface of the base plate 1, a fixed disk 4 disposed on the upper surface of the box 2, a drive disk 5 connected to the upper surface of the fixed disk 4, a short arm 6 connected to the upper portion of the drive disk 5, a support arm 7 connected to the inner side of the short arm 6, a connection arm 8 disposed on one side of the support arm 7, a support 9 mounted on the upper end of the support arm 7, a rotary joint 10 connected to the upper portion of the support 9, a lever 11 connected to one side of the rotary joint 10, an arm end joint 12 connected to one end of the lever 11, a pressure reducing support 13 disposed on the outer side of the arm end joint 12, the pressure reducing support 13 disposed on the outer side of the arm end joint 12, and transmitted by the pressure reducing support 13 when the arm end joint 12 is stressed, the pressure reduction function is realized, so that the arm end joint 12 is protected;
a power supply box 15 and a first motor 14 are arranged on one side surface of the box body 2, the power supply box 15 and the first motor 14 are arranged in parallel, a gear rod 16 is connected to one side of the first motor 14, a sealing seat 17 is connected to one end of the gear rod 16, a driven gear 18 is arranged in the box body 2, the gear rod 16 is driven by the first motor 14 to rotate, the driven gear 18 is driven by the gear on the gear rod 16 to rotate, the driven gear 18 drives the driving disk 5 to rotate through a turntable, the short arm 6 is driven to rotate in the horizontal direction by the rotation of the driving disk 5, and the supporting arm 7 and the arm lever 11 are driven to rotate through the short arm 6, so that the azimuth change and the operation of the mechanical arm assembly in the horizontal direction are completed;
the lower surface of the support 9 is provided with chucks 19 close to both sides, the lower surface of the support 9 is provided with a fixed shaft 20 close to the rear part, the upper surface of the support 9 is provided with a first conjunction block 21 and two groups of second conjunction blocks 22, and the two groups of second conjunction blocks 22 are positioned on both sides of the first conjunction block 21;
a second motor 23 is arranged on one side of the rotary joint 10, a first conjunction groove 24 and a second conjunction groove 25 are arranged on the lower surface of the rotary joint 10, a fastening block 26 is arranged on one side of the rotary joint 10 close to the bottom, a compression cylinder 27 is arranged at the upper end inside the fastening block 26, a movable block 28 is arranged at the lower end inside the fastening block 26, a top block 29 is arranged inside the movable block 28, a cushion block 31 is arranged at the lower end of the movable block 28, a clamping seat 30 is embedded and installed at the upper end inside the cushion block 31, the first conjunction groove 24 and the second conjunction groove 25 are in conjunction with the first conjunction block 21 and the second conjunction block 22, the top block 29 is pushed into the clamping seat 30 through the compression cylinder 27, the movable block 28 is further pushed out to enable the cushion block 31 to be in contact with the support 9, the cushion block 31 is in contact with the upper surface of the support 9 to play a role of buffering, after the cushion block 31 is in contact with the support 9, the movable block 28 is in a pushing state, thereby completing the connection of the arm 7 and the arm lever 11;
the pressure reducing support 13 comprises two groups of transverse supporting rods 32, a movable rotating shaft 33 is arranged between the front surface and the rear surface of each transverse supporting rod 32 in a penetrating mode, the upper surface of each transverse supporting rod 32 is connected with an upper fixing frame 34, the lower surface of each transverse supporting rod 32 is connected with a lower fixing frame 35, the pressure reducing support 13 is attached to the two side surfaces of the rotary joint 10 through the two groups of transverse supporting rods 32, the upper fixing frames 34 and the lower fixing frames 35 are respectively attached to the upper surface and the lower surface of the rotary joint 10, so that the surface of the rotary joint 10 is fixed, and the two groups of transverse supporting rods 32 can be slightly adjusted due to the existence of the movable rotating shaft 33, so that fine adjustment requirements are met;
the translation frame 3 comprises a first transverse rod 36 and a second transverse rod 37, extension plates 38 are mounted on the outer sides of the first transverse rod 36 and the second transverse rod 37, two groups of connecting rods 39 are connected between the first transverse rod 36 and the second transverse rod 37, the two groups of connecting rods 39 are arranged in parallel, translation sliding rails 40 are embedded in the inner sides of the first transverse rod 36 and the second transverse rod 37, two groups of reinforcing rods 41 are connected between the two groups of connecting rods 39, the two groups of reinforcing rods 41 are arranged in parallel, the translation frame 3 is pushed, the translation sliding rails 40 slide in the first transverse rod 36 and the second transverse rod 37, the bottom plate 1 is driven to perform horizontal position deviation, the box body 2 on the upper portion of the bottom plate 1 is driven to complete position adjustment in the horizontal direction, and the horizontal position adjustment of the whole mechanical arm is completed.
The total length of the translation frame 3 is equal to the length of the bottom plate 1, the upper surfaces of the first transverse rod 36 and the second transverse rod 37 on the translation frame 3 are connected with the lower surface of the bottom plate 1 in a welding mode, the upper surfaces of the translation slide rails 40 are connected with the first transverse rod 36 and the second transverse rod 37 in a sliding mode, and the upper surfaces of the translation slide rails 40 are connected with the lower surface of the bottom plate 1 in a welding mode.
The center in the fixed disk 4 is clamped with a turntable, the upper part of the turntable is connected with the lower part of the driving disk 5, and the driving disk 5 is driven to rotate through the rotation of the turntable.
The side of seal receptacle 17 is circular setting, and one side joint of seal receptacle 17 is inside one side of box 2, and seal receptacle 17 seals the one end of gear pole 16, avoids the one end of gear pole 16 to expose outside, and can not cause the influence to the rotation of gear pole 16 simultaneously.
The first fitting groove 24 and the second fitting groove 25 are fitted with the first fitting block 21 and the second fitting block 22, and the width of the first fitting block 21 is three times that of the second fitting block 22.
One end of the connecting arm 8 is movably connected with the inner surface of the fixed shaft 20, the inclination of the connecting arm 8 is the same as that of the support arm 7, the connecting arm 8 reinforces the support arm 7, and the inclination of the connecting arm 8 is changed when the inclination of the support arm 7 is changed.
The length of support arm 7 is greater than the length of armed lever 11, and armed lever 11 is cylindricly set up, and the rear surface of horizontal branch 32 links up with the one end surface of armed lever 11 mutually.
The width of extension plate 38 is less than the width of first transverse bar 36 and second transverse bar 37, and runs through the upper and lower surface of extension plate 38 and seted up a plurality of groups installation screw, and a plurality of groups installation screw are horizontal word equidistance and arrange, and external fixed screw to installation screw on extension plate 38 fixes extension plate 38 and contact surface, and extension plate 38 is fixed, and whole arm subassembly is fixed.
A plurality of groups of bevel gears are arranged on the periphery of the gear rod 16, the bevel gears are matched with peripheral gears of the driven gear 18, and the driven gear 18 is driven to rotate by the rotation of the gear rod 16 through the matching of the bevel gears and the peripheral gears of the driven gear 18.
When the invention is used, firstly, the bottom plate 1 is fixed on the contact surface through the extension plate 38, the extension plate 38 is externally connected with a fixing screw to an installation screw hole, the extension plate 38 and the contact surface are fixed, the whole mechanical arm assembly is fixed, the translation frame 3 is pushed according to the use condition, the translation slide rail 40 slides in the first transverse rod 36 and the second transverse rod 37 to drive the bottom plate 1 to carry out position deviation in the horizontal direction, the box body 2 at the upper part of the bottom plate 1 is driven by the bottom plate 1 to complete position adjustment in the horizontal direction, the position adjustment in the horizontal direction of the whole mechanical arm is completed, thereby the adjustment in the horizontal direction of the mechanical arm assembly can be realized after the mechanical arm assembly is fixed, the mechanical arm assembly can be adjusted according to the specific use condition, the adjustability of the mechanical arm assembly is more flexible, and the use requirements of different environments can be met, the connecting rod 39 reinforces the first transverse rod 36 and the second transverse rod 37, and the connecting rod 39 is reinforced by two groups of reinforcing rods 41, so that the whole translation frame 3 has better stability and is firmer, the first conjunction groove 24 and the second conjunction groove 25 are matched with the first conjunction block 21 and the second conjunction block 22, the fastening block 26 is adjusted to be in a fastening state, the top block 29 is pushed into the clamping seat 30 through the compression cylinder 27, the movable block 28 is further pushed out to enable the cushion block 31 to be in contact with the support seat 9, the cushion block 31 is in contact with the upper surface of the support seat 9 to play a role of buffering, after the cushion block 31 is in contact with the support seat 9, the movable block 28 is in a pushing state, so that the connection between the support arm 7 and the arm rod 11 is completed, the power supply box 15 is electrified, the first motor 14 is started, the first motor 14 drives the gear rod 16 to rotate, the gear on the gear rod 16 drives the driven gear 18 to rotate, the sealing seat 17 seals one end of the gear rod 16, so as to prevent one end of the gear rod 16 from being exposed outside and not influencing the rotation of the gear rod 16, the turntable is clamped at the center inside the fixed disk 4, the upper part of the turntable is connected with the lower part of the driving disk 5, the driving disk 5 is driven to rotate through the rotation of the turntable, the short arm 6 is driven to rotate in the horizontal direction through the rotation of the driving disk 5, so that the rotation requirement of the mechanical arm assembly in each direction in the horizontal range can be met, different operation directions can be met, the short arm 6 drives the support arm 7 and the arm rod 11 to rotate, the azimuth change and operation of the mechanical arm assembly in the horizontal direction are completed, other motors are externally connected at the joint of the short arm 6, the support arm 7 and the arm rod 11, the inclination adjustment of the support arm 7 and the arm rod 11 in the vertical direction is completed through the bending of the motors, the inclination of the connecting arm 8 is the same as the inclination of the arm 7, the connecting arm 8 reinforces the arm 7, when the inclination of the arm 7 changes, the inclination of the connecting arm 8 changes, the rotary joint 10 can be rotated by the second motor 23, thereby driving the arm rod 11 to swing up and down, the arm end joint 12 is connected with a manipulator so as to clamp a workpiece to be processed, the decompression bracket 13 is attached to two side surfaces of the rotary joint 10 through two groups of transverse supporting rods 32, the upper fixing frame 34 and the lower fixing frame 35 are respectively attached to the upper surface and the lower surface of the rotary joint 10, thereby completing the fixation with the surface of the rotary joint 10, the existence of the movable rotating shaft 33 enables the two groups of transverse supporting rods 32 to be slightly adjusted, the requirement of fine adjustment is met, when the arm end joint 12 is stressed, the pressure reduction effect is achieved through the conduction of the pressure reduction support 13, and therefore the arm end joint 12 is protected.
According to the invention, the translation frame 3 is arranged on the lower surface of the bottom plate 1, when the mechanical arm assembly needs to be adjusted in the horizontal direction after being fixed, the translation frame 3 is pushed, the translation slide rail 40 slides in the first transverse rod 36 and the second transverse rod 37 to drive the bottom plate 1 to shift the position in the horizontal direction, the bottom plate 1 drives the box body 2 on the upper part of the bottom plate to complete position adjustment in the horizontal direction, and the position adjustment in the horizontal direction of the whole mechanical arm is completed, so that after the mechanical arm assembly is fixed, the adjustment in the horizontal direction of the mechanical arm assembly can be realized, the mechanical arm assembly can be adjusted according to specific use conditions, and the problem that the traditional mechanical arm assembly is inconvenient to adjust in the horizontal direction after being installed and fixed is solved; the first conjunction groove 24 and the second conjunction groove 25 are arranged at the joint of the support 9 and the rotary joint 10 to be matched with the first conjunction block 21 and the second conjunction block 22, the fastening block 26 is matched, after the first conjunction groove 24 and the second conjunction groove 25 are matched with the first conjunction block 21 and the second conjunction block 22, the fastening block 26 is adjusted to be in a fastening state, the top block 29 is pushed into the clamping seat 30 through the compression air cylinder 27, the movable block 28 is further pushed out to enable the cushion block 31 to be in contact with the support 9, the cushion block 31 is in contact with the upper surface of the support 9 to play a role in buffering, after the cushion block 31 is in contact with the support 9, the movable block 28 is in a pushing state to complete the connection of the support arm 7 and the arm rod 11, and through the conjunction and matching of the conjunction groove and the fastening block 26, the support 9 and the rotary joint 10 have better firmness performance when being connected, so that the support arm 7 and the arm rod 11 are better in connection effect, the stability is better when the device works, and the loosening and falling-off are not easy to occur; through the periphery at arm end joint 12 set up decompression support 13, decompression support 13 laminates at rotary joint 10's both sides face through two sets of horizontal branch 32, fixed frame 34 and lower fixed frame 35 laminate with rotary joint 10's upper and lower surface respectively, thereby accomplish with rotary joint 10 surperficial fixed, the existence of activity pivot 33 makes two sets of horizontal branch 32 can carry out slight adjustment, satisfy the fine setting demand, when arm end joint 12 atress, the one end of two sets of horizontal branch 32 laminates with rotary joint 10 mutually, through the holistic conduction of decompression support 13, play the decompression effect, thereby protect arm end joint 12, make arm end joint 12 atress can even atress, service life when having improved arm end joint 12 atress.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.