CN112664507A

CN112664507A - Hydraulic cylinder for hoisting equipment

Info

Publication number: CN112664507A
Application number: CN202011549284.1A
Authority: CN
Inventors: 王宏盈; 王宏星; 侯先展
Original assignee: Jiangsu Zhengfeng Hydraulic Technology Co ltd
Current assignee: Jiangsu Zhengfeng Hydraulic Technology Co ltd
Priority date: 2020-12-24
Filing date: 2020-12-24
Publication date: 2021-04-16
Anticipated expiration: 2040-12-24
Also published as: CN112664507B

Abstract

The application relates to a hydraulic cylinder for hoisting equipment, which relates to the field of hydraulic devices and comprises a cylinder body and a piston rod coaxially arranged on the cylinder body, wherein the tail end of the cylinder body and one end of the piston rod, which extends out of the cylinder body, are provided with lugs, the piston rod is arranged at one end in the cylinder body and is provided with a piston, the inner cavity of the cylinder body is provided with a plurality of spiral guide grooves, the spiral guide grooves are uniformly distributed around the axis of the cylinder body, and the side wall of the piston is provided with a guide block clamped into the spiral; the hangers at the tail end of the piston rod are rotationally connected with the piston rod and can rotate by taking the axis of the piston rod as a shaft. This application has the effect that can reduce the pneumatic cylinder piston both sides degree of wear for hoisting equipment poor, extension pneumatic cylinder life.

Description

Hydraulic cylinder for hoisting equipment

Technical Field

The application relates to the field of hydraulic devices, in particular to a hydraulic cylinder for hoisting equipment.

Background

The hydraulic cylinder is a hydraulic actuator which converts hydraulic energy into mechanical energy and makes linear reciprocating motion (or swinging motion), and is widely applied to hydraulic systems of various machines. The hydraulic cylinder is basically composed of a cylinder barrel and a cylinder cover, a piston and a piston rod, a sealing device, a buffering device and an exhaust device. The damping device and the exhaust device are determined according to specific application occasions, and other devices are indispensable.

The output force of the hydraulic cylinder is in direct proportion to the effective area of the piston and the pressure difference between the two sides of the piston. On hoisting equipment, the tail end of a cylinder barrel of a hydraulic cylinder and the tail end of a piston rod are connected through rotating shafts, the cylinder barrel and the piston rod move relatively along the circumferential direction through hydraulic change in a lifting process of a cargo boom, and the whole hydraulic cylinder rotates by taking the rotating shafts at two ends as a center. Because the relative motion direction of cylinder and piston rod and the whole rotation direction of pneumatic cylinder do not coincide for the piston that is located in the cylinder is when the motion, and piston and cylinder inner wall ventral butt one side compare in with cylinder inner wall dorsal part butt one side degree of wear big, and then lead to the weeping scheduling problem, shortened the life of pneumatic cylinder. This problem is more pronounced in lifting equipment cylinders with larger strokes.

Although the related art has a hydraulic cylinder with a rotatable piston rod, certain disadvantages still exist, and further improvement is needed. For example, chinese patent application publication No. CN106015166A discloses a telescopic hydraulic cylinder with a rotatable piston rod, wherein splines formed on an inner edge of a piston rod are matched with key grooves formed at a front end of a gear shaft, so that the piston rod and the gear shaft can keep concentric and same speed in a rotating process, the gear shaft is matched with a swinging cylinder barrel and a rack to provide power output for the rotation of the piston rod, and the piston rod is matched with the telescopic cylinder barrel to provide power for the extension and retraction of the piston rod, thereby realizing the functions of extension and retraction and rotation of the piston rod, and alleviating the problems to a certain extent. However, the hydraulic cylinder needs to be matched with an additional driving device to realize circumferential rotation of the piston rod, so that the production cost is high and the use is limited; when the device is used for hoisting equipment, the problems of gear shaft and rack sliding are easy to occur due to large load; in addition, the effective stress area of the piston is reduced compared with that of the conventional hydraulic cylinder, so that the output force of the hydraulic cylinder is limited.

Chinese patent application No. CN110529455A discloses a hydraulic cylinder with a rotatable piston rod, in which a rear cover is fixed with a guide pin axis along the axis, the outer side of the guide axis is provided with a plurality of curved guide slots, the rear part of the piston rod is provided with a guide hole for the guide pin axis to penetrate, and the rear part of the piston rod is further fixed with a rotation driving assembly matching with the guide slots. When the piston rod of the hydraulic oil cylinder is axially stretched, the rotary driving assembly is matched with the guide groove to enable the piston rod to rotate, and the stretching and the rotating of the piston rod can be simultaneously completed. However, in the hydraulic cylinder, a guide hole for the pin axis to penetrate through needs to be formed in the piston rod, so that the effective stressed area is reduced while the strength of the piston rod is weakened, and the output force of the hydraulic cylinder is reduced under the condition of the same hydraulic pressure difference.

There are thus also new alternative solutions to the aforementioned problems.

Disclosure of Invention

In order to reduce for hoisting equipment pneumatic cylinder piston both sides degree of wear poor, extension pneumatic cylinder life, this application provides a pneumatic cylinder for hoisting equipment.

The application provides a pneumatic cylinder for hoisting equipment adopts following technical scheme:

a hydraulic cylinder for hoisting equipment comprises a cylinder body and a piston rod coaxially arranged on the cylinder body, wherein hanging lugs are arranged at the tail end of the cylinder body and the end, extending out of the cylinder body, of the piston rod, a piston is arranged at one end, located in the cylinder body, of the piston rod, a plurality of spiral guide grooves are formed in the inner cavity of the cylinder body and are uniformly distributed around the axis of the cylinder body, and guide blocks clamped into the spiral guide grooves are arranged on the side wall of the piston; the ratio of the thread pitch of the spiral guide groove 111 to the diameter of the piston 3 is more than or equal to 1; the hangers at the tail end of the piston rod are rotationally connected with the piston rod and can rotate by taking the axis of the piston rod as a shaft.

Through adopting above-mentioned technical scheme, under the poor driving about of hydraulic pressure, piston and piston rod along cylinder body axial displacement, this in-process guide block slides along spiral guide slot for the piston block circumference rotation when axial displacement, so make the even atress of piston periphery, it is poor to have reduced the degree of wear between piston periphery and cylinder body inner wall ventral side and the dorsal part, thereby has prolonged the life of pneumatic cylinder. The hangers at the tail end of the piston rod are rotationally connected and matched with the circumferential rotation of the piston and the piston rod.

Optionally, the spiral guide groove is provided with 2-6.

Through adopting above-mentioned technical scheme, can be so that the piston can the even atress when along cylinder body axial motion, and then synchronous circumference rotation. The spiral guide groove sets up the quantity too much, has increased the manufacturing degree of difficulty of pneumatic cylinder, also makes the guide block volume undersize of card income single spiral guide groove in, is unfavorable for long-time reciprocating work, therefore with 2~6 spiral guide grooves most suitable, preferred 3~ 4.

Optionally, the projection shape of the spiral guide groove on a plane perpendicular to the cylinder axis is crescent-shaped.

Through adopting above-mentioned technical scheme, the connection between guide block and the piston is excessive natural, also does not have sharp-pointed edges and corners, and the equal preferred long service life of wearability, leakproofness also can smoothly slide in the spiral guide slot, and the card pause is difficult for appearing. Meanwhile, when the piston is processed and manufactured, the piston and the guide block can be conveniently and integrally formed.

Optionally, one end of the piston rod, which extends out of the cylinder body, is provided with a spherical block, a mounting shell is coated outside the spherical block, and the piston rod penetrates through the mounting shell; the opening side of installation shell cover is equipped with the installation piece, and the hangers is fixed to be set up in installation piece and deviates from spherical piece one side.

Through adopting above-mentioned technical scheme, can enough adapt to the circumferential direction of piston rod and piston, the spherical piece also can disperse pressure simultaneously, does not influence the pneumatic cylinder load for the pneumatic cylinder of this application is applicable to hoisting equipment, still can normally work under great pressure.

Optionally, a section of limiting pipe located outside the mounting shell is coaxially sleeved on the piston rod, and the limiting pipe is fixedly connected to the outer wall of the mounting shell.

Through adopting above-mentioned technical scheme for piston rod, spherical piece and spacing pipe keep better axiality, can more smoothly circumferential direction.

Optionally, the mounting block is provided with a groove for the spherical block to be clamped in.

By adopting the technical scheme, the grooves can increase the rotation stability of the spherical blocks, so that the spherical blocks can better bear pressure, and the service life of the hydraulic cylinder is prolonged.

Optionally, an oil injection channel communicated with the groove is arranged on the mounting block.

By adopting the technical scheme, lubricating oil can be conveniently injected into the groove by virtue of the oil injection channel, so that the rotation flexibility of the spherical block is improved.

Optionally, the piston comprises a metal ring plate and rubber ring plates positioned at two sides of the metal ring plate; the rubber ring plate is sleeved on the piston rod and is detachably connected with the metal ring plate; the metal ring plate periphery is provided with the first bellying of card income spiral guide slot, the rubber ring plate periphery is equipped with the second bellying of card income spiral guide slot, first bellying and second bellying constitute the guide block jointly.

Through adopting above-mentioned technical scheme to metal ring plate and the rubber ring board that is located metal ring plate both sides constitute the piston jointly, not only have better leakproofness between with the cylinder body inner wall, have good wearability moreover, and life is longer. In addition, compared with the related art, the piston rod is not required to be provided with a guide hole or a blind hole, and the effective stress area is not reduced, so that the negative influence on the output force of the hydraulic cylinder is reduced.

Optionally, the piston rod is further sleeved with two limiting rings, the limiting rings are detachably connected with the piston rod, and the rubber ring plate and the metal ring plate are clamped between the two limiting rings.

Through adopting above-mentioned technical scheme, further increased the installation fastness between metal ring board and the rubber ring board, prolonged the life of pneumatic cylinder.

Optionally, a fixing block is arranged on the rubber ring plate, a fixing groove for the fixing block to be clamped is formed in the metal ring plate, and a fastening bolt for fastening the fixing block to the fixing groove is arranged on the periphery of the metal ring plate.

Through adopting above-mentioned technical scheme, can realize the fastness stable connection of rubber ring board and metal environmental protection, also can dismantle the maintenance fast to the piston when necessary.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the inner wall of the cylinder body is provided with the plurality of spiral guide grooves, the periphery of the piston is provided with the guide block clamped in the spiral guide grooves, so that the piston and the piston rod can rotate in the circumferential direction while moving in the axial direction, the periphery of the piston is uniformly stressed, the difference of abrasion degree between the piston and the belly-back side contact part of the inner wall of the cylinder body is reduced, and the service life of the hydraulic cylinder is longer;

2. the hangers at the tail end of the piston rod are rotationally connected through the mounting block, the spherical block and the mounting shell sleeve, so that the rotary connection structure can adapt to the rotation of the piston rod and can adapt to occasions where hoisting equipment needs to carry loads;

3. the piston is composed of a metal ring plate and two layers of rubber ring plates, and has good sealing performance, good wear resistance and longer service life.

Drawings

Fig. 1 is a schematic structural view of a hydraulic cylinder for a hoisting device according to embodiment 1 of the present invention.

Fig. 2 is a sectional view of the mounting case, the mounting block, and the suspension loop according to embodiment 1 of the present application.

Fig. 3 is a sectional view of the cylinder tube in embodiment 1 of the present application.

Fig. 4 is a schematic cross-sectional view of a cylinder block of embodiment 1 of the present application.

Fig. 5 is a schematic structural view of a piston according to embodiment 1 of the present application.

Fig. 6 is a sectional view of a hydraulic cylinder for a hoisting device according to embodiment 1 of the present application.

Fig. 7 is an enlarged view of a portion a in fig. 6.

Fig. 8 is a schematic cross-sectional view of a cylinder block of embodiment 2 of the present application.

Description of reference numerals: 1. a cylinder body; 11. a cylinder barrel; 111. a spiral guide groove; 12. a cylinder cover; 2. a piston rod; 21. a spherical block; 3. a piston; 31. a metal ring plate; 311. fixing grooves; 312. fastening the bolt; 32. a rubber ring plate; 321. a fixed block; 33. a limiting ring; 331. locking the bolt; 34. an arc-shaped slot; 4. hanging a lug; 41. mounting blocks; 411. a groove; 412. an oil injection channel; 4121. a threaded cock; 5. mounting a shell; 51. installing a bolt; 52. a limiting pipe; 6. a guide block; 61. a first boss portion; 62. a second boss.

Detailed Description

The present application is described in further detail below with reference to figures 1-8.

The embodiment of the application discloses hydraulic cylinder for hoisting equipment.

Example 1

Referring to fig. 1, the hydraulic cylinder for a lifting apparatus includes a cylinder body 1 and a piston rod 2. The cylinder body 1 is composed of a hollow cylindrical cylinder barrel 11 and cylinder covers 12 hermetically arranged at both ends of the cylinder barrel 11. The piston rod 2 is coaxially inserted into the cylinder body 1, one end of the piston rod is positioned in the cylinder barrel 11, and the other end of the piston rod penetrates through the cylinder cover 12 at one end of the cylinder body 1. The cylinder cover 12 at the tail end of the cylinder body 1 and one end of the piston rod 2 extending out of the cylinder body 1 are both provided with a hanging lug 4, and the hanging lugs 4 at the tail end of the cylinder body 1 are fixedly connected.

Referring to fig. 1 and 2, the lug 4 at the end of the piston rod 2 is rotatably connected with the piston rod 2, and the lug and the piston rod can rotate relatively in the circumferential direction by taking the axis of the piston rod 2 as an axis. The hanging lug 4 is fixedly arranged through a mounting block 41, and a spherical block 21 is fixedly arranged at the tail end of the piston rod 2. The spherical block 21 is covered with a hemispherical mounting shell 5, and the piston rod 2 penetrates through the mounting shell 5 and is coaxially arranged with the mounting shell. The mounting block 41 is plugged at the opening side of the mounting shell 5, and the mounting block and the mounting shell are fixedly connected through a plurality of mounting bolts 51 which are uniformly distributed along the circumferential direction of the mounting shell 5. In order to ensure that the spherical block 21, the piston rod 2 and the mounting shell 5 have good coaxiality, a section of limiting pipe 52 is fixedly arranged on the mounting shell 5, and the piston rod 2 is sleeved with the limiting pipe 52.

Referring to fig. 2, the mounting block 41 is further provided with a hemispherical recess 411, and the spherical block 21 is partially inserted into the recess 411, so that the pressure bearing capacity of the spherical block 21 is increased without interfering with the rotation of the spherical block 21. Meanwhile, an oil filling channel 412 communicated with the groove 411 is formed in the side surface, away from the piston rod 2, of the mounting block 41, and a threaded cock 4121 is connected to the opening of the oil filling channel 412 in a threaded mode. Lubricating oil can be injected into the groove 411 by means of the oil injection passage 412 so that the spherical block 21 can be more smoothly rotated. The screw tap 4121 is used to close off the filler passage 412 to block debris.

Referring to fig. 3 and 4, the piston 3 is provided at one end of the piston rod 2 located inside the cylinder 11. The inner wall of the cylinder 11 is provided with a plurality of spiral guide grooves 111 which are uniformly distributed around the axis of the cylinder 11. The periphery of the piston 3 is provided with a plurality of guide blocks 6 which are clamped into the spiral guide grooves 111. The length of the spiral guide groove 111 is enough for the piston 3 to move along the full stroke of the cylinder barrel 11, the ratio of the pitch of the spiral guide groove 111 to the diameter of the piston 3 is more than or equal to 1, and the ratio of the length of the inner cavity of the cylinder body 1 to the pitch of the spiral guide groove 111 is more than or equal to 1, so that the piston 3 can smoothly rotate for at least one circle under the action of hydraulic pressure difference, and the periphery of the piston 3 is uniformly stressed. In this embodiment, the ratio of the pitch of the spiral guide groove 111 to the diameter of the piston 3 is equal to 2, and in other embodiments, the ratio of the pitch of the spiral guide groove 111 to the diameter of the piston 3 is generally larger to facilitate the rotation of the piston 3. The piston 3 is allowed to rotate circumferentially by the engagement of the guide 6 with the spiral guide groove 111 while the piston 3 moves axially in the cylinder 11. The number of the spiral guide grooves 111 can be set according to actual needs, and 2-6 spiral guide grooves 111 are preferable from the aspects of manufacturing difficulty and working stability, and the number of the spiral guide grooves 111 is 4 in the embodiment. The number of the guide blocks 6 is the same as that of the spiral guide grooves 111, and the guide blocks correspond to the spiral guide grooves one by one.

Referring to fig. 4, in the present embodiment, the projection shapes of the spiral guide groove 111 and the guide block 6 on the plane perpendicular to the axial direction of the cylinder 11 are crescent, so that the two can not only be in sealing fit, but also are not easy to wear. In other embodiments, other shapes may be provided, such as triangular, trapezoidal, rectangular, etc.

Referring to fig. 5, the piston 3 includes a metal ring plate 31 coaxially disposed on the piston rod 2, and the metal ring plate 31 is fixedly connected to the piston rod 2. Two sides of the metal ring plate 31 are respectively provided with a rubber ring plate 32, the piston rod 2 is sleeved with the rubber ring plate 32, and the rubber ring plate 32 and the metal ring plate 31 are detachably and fixedly connected. The guide block 6 is composed of a first convex portion 61 arranged on the outer edge of the metal ring plate 31 and a second convex portion 62 arranged on the outer edge of the rubber ring plate 32, and is in a spiral strip shape.

Referring to fig. 6 and 7, the metal ring plate 31 is provided with a fixing groove 311, and the rubber ring plate 32 is provided with a fixing block 321 which is inserted into the fixing groove 311. The fixing blocks 321 on the two rubber ring plates 32 are arranged in a staggered mode in the radial direction of the piston 3, and in order to improve the connection stability, the fixing blocks 321 are arranged on the piston 3 at intervals in the circumferential direction. The circumferential side wall of the metal ring plate 31 is provided with a fastening bolt 312, and the fastening bolt 312 penetrates through the fixing groove 311 and the fixing block 321 along the radial direction of the piston 3, so that the rubber ring plate 32 and the metal ring plate 31 are firmly connected.

Referring to fig. 6 and 7, in order to increase the overall structural stability of the piston 3, a stopper ring 33 is further provided on each of both sides of the piston 3. The limiting ring 33 is sleeved on the piston rod 2 and tightly connected with the rubber ring plate 32. A plurality of locking bolts 331 penetrate through the periphery of the limiting ring 33 along the radial direction, and the locking bolts 331 are inserted into the piston rod 2 to fixedly connect the limiting ring 33 and the piston rod 2.

The implementation principle of the hydraulic cylinder for the hoisting equipment in the embodiment of the application is as follows: the inner wall of the cylinder barrel 11 of the cylinder body 1 is provided with the plurality of spiral guide grooves 111, the periphery of the piston 3 is provided with the plurality of guide blocks 6 clamped into the spiral guide grooves 111, and meanwhile, the hanging lug 4 is rotatably connected with the piston rod 2, so that when the piston 3 axially moves in the cylinder body 1, no additional driving mechanism is needed, the guide blocks 6 are matched with the spiral guide grooves 111 to enable the piston 3 to circumferentially rotate, the periphery of the piston 3 is uniformly rubbed with the inner wall of the cylinder barrel 11, the abrasion degree of two sides is weakened, and the service life of the hydraulic cylinder is prolonged. Meanwhile, the hydraulic cylinder for the hoisting equipment does not need to be provided with a blind hole or a guide hole on the piston rod 2 or the piston 3, so that the effective stress area of the piston 3 is not influenced, and the negative influence on the output force of the hydraulic cylinder is reduced to the greatest extent.

Example 2

Referring to fig. 8, embodiment 2 differs from embodiment 1 only in that: the end face of the piston 3 is provided with a plurality of arc-shaped grooves 34 which are uniformly distributed along the circumferential direction of the piston 3, and the depths of the arc-shaped grooves 34 on the same end face are gradually increased from one end to the other end along the same direction, so that the bottom surfaces of the arc-shaped grooves 34 have certain gradients. When the hydraulic cylinder works, the hydraulic pressure acting on the end face of the piston 3 can form a component force with the tendency of driving the piston 3 to rotate in the circumferential direction on the bottom surface of the arc-shaped groove 34 with inclination, and the component force enables the piston 3 to rotate in the circumferential direction more easily and is not easy to clamp. In embodiment 2, two arc-shaped grooves 34 are provided, the central angles of the two arc-shaped grooves 34 are both 150 °, and the two arc-shaped grooves 34 are distributed around the center of the end surface of the piston 3 in a central symmetry manner.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a pneumatic cylinder for hoisting equipment, includes cylinder body (1) and coaxial setting in piston rod (2) of cylinder body (1), cylinder body (1) end and piston rod (2) stretch out one end from cylinder body (1) and all are equipped with hangers (4), piston rod (2) are located cylinder body (1) one end and are equipped with piston (3), its characterized in that: the inner cavity of the cylinder body (1) is provided with a plurality of spiral guide grooves (111), the spiral guide grooves (111) are uniformly distributed around the axis of the cylinder body (1), and the side wall of the piston (3) is provided with a guide block (6) clamped in the spiral guide grooves (111); the ratio of the thread pitch of the spiral guide groove (111) to the diameter of the piston (3) is more than or equal to 1; the hanging lug (4) at the tail end of the piston rod (2) is rotatably connected with the piston rod (2), and the hanging lug (4) can rotate by taking the axis of the piston rod (2) as a shaft.

2. The hydraulic cylinder for hoisting equipment according to claim 1, wherein: the spiral guide groove (111) is provided with 2-6 spiral guide grooves.

3. The hydraulic cylinder for hoisting equipment according to claim 2, wherein: the projection shape of the spiral guide groove (111) on the plane vertical to the axis of the cylinder body (1) is crescent.

4. The hydraulic cylinder for hoisting equipment according to claim 1, wherein: one end of the piston rod (2) extending out of the cylinder body (1) is provided with a spherical block (21), a mounting shell sleeve (5) is coated outside the spherical block (21), and the piston rod (2) penetrates through the mounting shell sleeve (5); the opening side of the mounting shell sleeve (5) is provided with a mounting block (41), and the hanging lugs (4) are fixedly arranged on one side, deviating from the spherical block (21), of the mounting block (41).

5. The hydraulic cylinder for hoisting equipment according to claim 4, wherein: the piston rod (2) is coaxially sleeved with a limiting pipe (52) located outside the mounting shell sleeve (5), and the limiting pipe (52) is fixedly connected to the outer wall of the mounting shell sleeve (5).

6. The hydraulic cylinder for hoisting equipment according to claim 4, wherein: the mounting block (41) is provided with a groove (411) for the spherical block (21) to be clamped in.

7. The hydraulic cylinder for hoisting equipment according to claim 6, wherein: and the mounting block (41) is provided with an oil injection channel (412) communicated with the groove (411).

8. The hydraulic cylinder for hoisting equipment according to any one of claims 1 to 7, wherein: the piston (3) comprises a metal ring plate (31) and rubber ring plates (32) positioned on two sides of the metal ring plate (31); the rubber ring plate (32) is sleeved on the piston rod (2) and is detachably connected with the metal ring plate (31); the metal ring plate (31) periphery is provided with first bellying (61) of going into spiral guide slot (111), rubber ring plate (32) periphery is equipped with second bellying (62) of going into spiral guide slot (111), first bellying (61) and second bellying (62) constitute guide block (6) jointly.

9. The hydraulic cylinder for hoisting equipment according to claim 8, wherein: piston rod (2) still cover and be equipped with two spacing rings (33), can dismantle between spacing ring (33) and piston rod (2) and be connected, rubber ring board (32) and metal ring board (31) are by the centre gripping between two spacing rings (33).

10. The hydraulic cylinder for hoisting equipment according to claim 9, wherein: the rubber ring plate (32) is provided with a fixing block (321), the metal ring plate (31) is provided with a fixing groove (311) for the fixing block (321) to be clamped in, and the periphery of the metal ring plate (31) is provided with a fastening bolt (312) for fastening the fixing block (321) to the fixing groove (311).