Novel multi-stage hydraulic cylinder

Abstract

The invention relates to the field of hydraulic cylinders, in particular to a novel multi-stage hydraulic cylinder which comprises a cylinder barrel, a sleeve, a retracting and releasing unit, a piston rod, a pushing unit, an opening and closing unit, a pushing plate, a cleaning unit and a connecting unit. On the other hand, when the sleeve and the piston rod extend to the maximum extent, the sleeve and the piston rod are locked through a clamping groove and a clamping block, so that pressure borne by all valves in a hydraulic system is reduced, and the situation that the multi-stage hydraulic cylinder loses supporting force after being supported for a long time is avoided as far as possible; and impurities attached to the side walls of the two collecting seats are collected in the inclined groove in the outer wall of the left collecting seat, and then the impurities in the inclined groove are pushed into the collecting groove through the L-shaped scraper, so that the cleaning effect is achieved.

Description

Technical Field

[0001] The invention relates to the field of hydraulic cylinders, and in particular to a novel multi-stage hydraulic cylinder. Background Art

[0002] The multi-stage hydraulic cylinder is a special hydraulic actuator, mainly used in applications where a long stroke is required but the installation space is limited. The characteristic of this hydraulic cylinder is that a longer extension distance can be achieved in a smaller installation space, and the required working stroke can be achieved by gradually extending or retracting multiple piston rods with different diameters.

[0003] The current multi-stage hydraulic cylinders have the following problems when in use: when the multi-stage hydraulic cylinders support heavy objects, the pressure borne by each valve in the hydraulic system is relatively large. If the support time is long, it is easy for the valve to leak internally, resulting in the inability to maintain the system pressure, and then the multi-stage hydraulic cylinder loses its supporting force; during the retraction process of the piston rod or sleeve in the multi-stage hydraulic cylinder, it is easy for it to be contaminated by impurities in the air. Long-term accumulation will make the oil flow unstable and cause the multi-stage hydraulic cylinder to shake; at the same time, when the weight carried by the multi-stage hydraulic cylinder suddenly changes, the multi-stage hydraulic cylinder will also be unable to adapt quickly and will shake. Summary of the invention

[0004] In order to solve the above problems, the present invention adopts the following technical solution: a new type of multi-stage hydraulic cylinder, including a cylinder barrel and a sleeve, both of which are cylindrical cavity structures, and the sleeve is slidably connected to the left end of the cylinder barrel. The cylinder barrel and the sleeve are jointly provided with a retracting and extending unit, the left end of the sleeve is slidably connected to a piston rod, and the right ends of the piston rod and the sleeve are both connected to a pushing unit.

[0005] The pushing unit connected to the right end of the sleeve includes a pushing piece, which is fixedly connected to the right end of the sleeve. A circular groove is opened on the No. 2 pushing piece from left to right, a connecting rod is arranged in the circular groove, rectangular grooves are symmetrically opened on the side walls of the pushing piece, a clamping groove corresponding to the rectangular groove is opened on the inner wall of the cylinder, a clamping block is slidably connected in the rectangular groove, and a No. 1 hinged seat is fixedly connected to the end of the clamping block close to the connecting rod, a No. 2 hinged seat corresponding to the No. 1 hinged seat is fixedly connected to the side wall of the connecting rod, a rectangular frame is hinged between the corresponding No. 1 hinged seat and No. 2 hinged seat, and the pushing unit connected to the right end of the piston rod has the same structure as the pushing unit connected to the right end of the sleeve.

[0006] An opening and closing unit is connected to the connecting rod in the cylinder, the right end of the connecting rod in the sleeve is rotatably connected to a push plate, the sleeve and the piston rod are both connected to a cleaning unit, a sealing block matching the cleaning unit is fixedly connected to the side wall of the push plate, and the left end of the piston rod is connected to a connecting unit.

[0007] Preferably, the retracting and releasing unit includes a No. 1 oil port, a No. 1 oil port is formed through the side wall of the cylinder and on the right end, a No. 2 oil port is fixedly formed on the side wall of the cylinder and on the left end, an oil delivery groove is formed in the sleeve, the right end of the oil delivery groove cooperates with the No. 2 oil port, the left end of the oil delivery groove is connected with the cavity in the sleeve, a cylindrical groove is formed on the right end face of the piston rod, and an oil port connected to the cylindrical groove is formed on the side wall of the piston rod.

[0008] Preferably, the opening and closing unit includes a No. 1 sealing plate, which is located in the sleeve cavity and fixedly connected to the push piece. The No. 1 sealing plate is provided with through grooves that match the circular grooves on the left and right sides. The left end of the connecting rod is fixedly connected to the No. 2 sealing plate. The left end surfaces of the No. 1 sealing plate and the No. 2 sealing plate are evenly provided with multiple fan-shaped notches along the circumferential direction, and the fan-shaped notches on the No. 1 sealing plate and the No. 2 sealing plate are staggered. The right end of the connecting rod is connected to a retaining assembly.

[0009] Preferably, the retaining assembly comprises a circular plate, the circular plate is fixedly connected to the right end of the linkage rod, and the circular plate and the push member are fixedly connected via a connecting spring.

[0010] Preferably, the cleaning unit connected to the sleeve includes a collecting seat, which is rotatably sleeved on the right end of the sleeve, the collecting seat and the cylinder are fixedly connected by a torsion spring, the left end of the sleeve is fixedly connected to a scraping seat, and a decontamination component is commonly provided on the collecting seat and the scraping seat.

[0011] Preferably, the dirt removal component includes an inclined groove, and the side wall of the collecting seat is evenly provided with a plurality of inclined grooves along the circumferential direction, the right ends of the inclined grooves are commonly connected with an annular groove, the right end surface of the scraper seat is evenly fixedly connected with a plurality of elastic scrapers along the circumferential direction, and the pushing member in the cylinder is connected with a rotating module cooperating with the scraper seat.

[0012] Preferably, the rotating module includes a spiral groove, the inner wall of the cylinder is provided with a spiral groove, the side wall of the push member is fixedly connected with a slider, the slider is slidingly connected in the spiral groove, and the slider and the spiral groove are sealed, the cleaning unit connected to the piston rod has the same structure as the cleaning unit connected to the sleeve, and the sealing block is slidingly connected in the spiral groove.

[0013] Preferably, the connecting unit comprises a connecting tube, which is a cylindrical cavity structure, the right end of the connecting tube is fixedly connected to the left end of the piston rod, the left end of the connecting tube is slidably connected to a sliding rod, the left end of the sliding rod is fixedly connected to a connecting plate, the connecting plate and the sliding rod are jointly connected to a shock absorbing assembly, the left end surface of the connecting plate and the right end of the cylinder are fixedly connected to a connecting piece,

[0014] Preferably, the shock absorbing assembly comprises an annular plate, the side wall of the connecting tube is fixedly sleeved with the annular plate, and the annular plate and the connecting plate are fixedly connected via a shock absorbing spring.

[0015] The beneficial effects of the present invention are as follows: 1. The present invention ensures that the sleeve and the piston rod can be extended step by step through the cooperation between the block and the slot in the push unit and the opening and closing unit. On the other hand, when the two are extended to the maximum, the block enters the slot to lock the two, so as to reduce the pressure on each valve in the hydraulic system and avoid as much as possible the loss of supporting force caused by the leakage of hydraulic oil in the multi-stage hydraulic cylinder after long-term support.

[0016] 2. When the piston rod or sleeve of the present invention is retracted, the slider in the cleaning unit slides along the threaded groove, which drives the piston rod or sleeve to rotate while retracting, thereby collecting impurities contaminated on the side wall in the inclined groove on the outer wall of the collecting seat. In the final stage of retraction, the elastic scraper enters the corresponding inclined groove and drives the collecting seat to rotate synchronously by a certain angle while sliding along the inclined groove. On the one hand, the torsion spring twists and accumulates force, and on the other hand, the impurities in the inclined groove are pushed into the collecting groove. After the elastic scraper is separated from the inclined groove, the collecting seat is driven by the torsion spring to quickly rotate and reset and generate centrifugal force, so that the impurities are separated from the collecting groove, thereby achieving the cleaning effect.

[0017] 3. In the present invention, the left connecting piece is connected to the weight. When the gravity of the weight suddenly decreases or increases, the shock-absorbing spring will correspondingly extend back or be further compressed, and the sliding rod will slide to the left or right relative to the sleeve to absorb the vibration, thereby avoiding the external force being transmitted to the piston rod and causing the piston rod to shake. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention is further described below with reference to the accompanying drawings and examples.

[0019] Figure 1 It is a three-dimensional structural schematic diagram of a novel multi-stage hydraulic cylinder of the present invention.

[0020] Figure 2 The present invention Figure 1 Top view of .

[0021] Figure 3 The present invention is the present invention Figure 2 Sectional view of AA.

[0022] Figure 4 A partial cross-sectional view of a novel multi-stage hydraulic cylinder of the present invention.

[0023] Figure 5 It is a three-dimensional structural schematic diagram of the left side pushing unit of the present invention.

[0024] Figure 6 The present invention Figure 3 A partial enlarged view of point A in the middle.

[0025] Figure 7 The present invention Figure 4 A partial enlarged view of point B in the middle.

[0026] Figure 8 The present invention Figure 1 A partial enlarged view of point C in the middle.

[0027] In the figure: 1, cylinder; 2, sleeve; 3, retracting unit; 31, oil port No. 1; 32, oil port No. 2; 33, oil delivery groove; 34, cylindrical groove; 35, oil through port; 4, piston rod; 5, push unit; 51, push member; 52, circular groove; 53, connecting rod; 54, rectangular groove; 55, clamping groove; 56, clamping block; 57, hinge seat No. 1; 58, hinge seat No. 2; 59, rectangular frame; 6, opening and closing unit; 61, sealing plate No. 1; 62, through groove; 63, sealing plate No. 2; 64, fan-shaped notch; 65. Holding assembly; 651. Circular plate; 652. Connecting spring; 7. Push plate; 71. Sealing block; 8. Cleaning unit; 81. Collecting seat; 82. Torsion spring; 83. Scraping seat; 84. Decontamination assembly; 841. Inclined groove; 842. Annular groove; 843. Elastic scraper; 844. Rotating module; 8441. Spiral groove; 8442. Sliding block; 9. Connecting unit; 91. Connecting cylinder; 92. Sliding rod; 93. Connecting plate; 95. Connecting piece; 941. Annular plate; 942. Shock-absorbing spring. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the invention can be implemented in many different ways as defined and covered by the claims.

[0029] See also Figure 1 and Figure 3 A new type of multi-stage hydraulic cylinder includes a cylinder barrel 1 and a sleeve 2. Both the cylinder barrel 1 and the sleeve 2 are cylindrical cavity structures. The sleeve 2 is slidably connected to the left end of the cylinder barrel 1. The cylinder barrel 1 and the sleeve 2 are jointly provided with a retracting unit 3. The left end of the sleeve 2 is slidably connected to a piston rod 4. The right ends of the piston rod 4 and the sleeve 2 are both connected to a pushing unit 5.

[0030] See also Figure 3 and Figure 4 The retracting and releasing unit 3 includes a No. 1 oil port 31, a No. 1 oil port 31 is formed through the side wall of the cylinder 1 and on the right end, a No. 2 oil port 32 is fixedly formed on the side wall of the cylinder 1 and on the left end, an oil delivery groove 33 is formed in the sleeve 2, the right end of the oil delivery groove 33 cooperates with the No. 2 oil port 32, the left end of the oil delivery groove 33 is connected to the cavity in the sleeve 2, a cylindrical groove 34 is formed on the right end face of the piston rod 4, and an oil through port 35 connected to the cylindrical groove 34 is formed on the side wall of the piston rod 4.

[0031] During specific operation, both the No. 1 oil port 31 and the No. 2 oil port 32 are connected to the external hydraulic system. When the sleeve 2 and the piston rod 4 need to be extended, the external hydraulic system introduces hydraulic oil into the cylinder 1 through the No. 1 oil port 31, and the hydraulic oil pushes the pushing unit 5 at the right end of the sleeve 2 to extend out of the cylinder 1 together with the sleeve 2. When the sleeve 2 is extended to the maximum limit, the hydraulic oil passes through the pushing unit 5 at the right end of the sleeve 2 into the sleeve 2, and pushes the pushing unit 5 at the right end of the piston rod 4 to extend out of the sleeve 2 together with the piston rod 4.

[0032] When it is necessary to retract the sleeve 2 and the piston rod 4, on the one hand, hydraulic oil is extracted from the No. 1 oil port 31 through the external hydraulic system, and on the other hand, hydraulic oil is introduced into the No. 2 oil port 32 through the external hydraulic system. The introduced hydraulic oil enters the sleeve 2 along the oil delivery groove 33, and then enters the cylindrical groove 34 along the oil passage 35. The hydraulic oil entering the cylindrical groove 34 pushes the pushing unit 5 at the right end of the piston rod 4 to move synchronously to the right together with the piston rod 4. When the piston rod 4 is completely retracted into the sleeve 2, the hydraulic oil is stopped from being introduced into the No. 2 oil port 32, and the hydraulic oil is continued to be pumped out from the No. 1 oil port 31, so as to push the pushing unit 5 at the right end of the sleeve 2 and retract the sleeve 2 into the cylinder 1 together.

[0033] See also Figure 3 , Figure 4 and Figure 6 The pushing unit 5 connected to the right end of the sleeve 2 includes a pushing member 51, which is fixedly connected to the right end of the sleeve 2. A circular groove 52 is opened on the second pushing member 51 from left to right, and a connecting rod 53 is arranged in the circular groove 52. A rectangular groove 54 is symmetrically opened on the side wall of the pushing member 51. A clamping groove 55 corresponding to the rectangular groove 54 is opened on the inner wall of the cylinder 1. A clamping block 56 is slidably connected in the rectangular groove 54. The end of the clamping block 56 close to the connecting rod 53 is fixedly connected to a No. 1 hinge seat 57, and a No. 2 hinge seat 58 corresponding to the No. 1 hinge seat 57 is fixedly connected to the side wall of the connecting rod 53. A rectangular frame 59 is hinged between the corresponding No. 1 hinge seat 57 and the No. 2 hinge seat 58. The pushing unit 5 connected to the right end of the piston rod 4 has the same structure as the pushing unit 5 connected to the right end of the sleeve 2.

[0034] See also Figure 3-Figure 6 The connecting rod 53 in the cylinder 1 is connected to the opening and closing unit 6, the right end of the connecting rod 53 in the sleeve 2 is rotatably connected to the push plate 7, the sleeve 2 and the piston rod 4 are both connected to the cleaning unit 8, the side wall of the push plate 7 is fixedly connected to the blocking block 71 that cooperates with the cleaning unit 8, and the left end of the piston rod 4 is connected to the connecting unit 9.

[0035] See also Figure 4 and Figure 6The opening and closing unit 6 includes a No. 1 sealing plate 61, which is located in the cavity of the sleeve 2 and fixedly connected to the push piece 51. The No. 1 sealing plate 61 is provided with through grooves 62 that match the circular grooves 52. The left end of the linkage rod 53 is fixedly connected with a No. 2 sealing plate 63. The left end surfaces of the No. 1 sealing plate 61 and the No. 2 sealing plate 63 are uniformly provided with a plurality of fan-shaped notches 64 along the circumferential direction, and the fan-shaped notches 64 on the No. 1 sealing plate 61 and the fan-shaped notches 64 on the No. 2 sealing plate 63 are staggered. The right end of the linkage rod 53 is connected with a retaining assembly 65, which includes a circular plate 651, which is fixedly connected to the right end of the linkage rod 53, and the circular plate 651 is fixedly connected to the push piece 51 through a connecting spring 652.

[0036] During specific operation, in the initial state, the sleeve 2 is retracted in the cylinder 1, and the piston rod 4 is retracted in the sleeve 2. At this time, due to the limitations of the inner walls of the cylinder 1 and the inner walls of the sleeve 2, the block 56 is located in the rectangular groove 54, and the two rectangular frames 59 are distributed in an eight-shaped shape and open to the left. The No. 1 sealing plate 61 and the No. 2 sealing plate 63 are spliced, and the connecting spring 652 is in a stretched state. When the sleeve 2 and the piston rod 4 need to be extended, hydraulic oil is introduced into the cylinder 1 through the No. 1 oil port 31. Under the push of the hydraulic oil, the push piece 51 at the right end of the sleeve 2 moves to the left, driving the sleeve 2 to extend synchronously to the left from the cylinder 1.

[0037] When the push piece 51 at the right end of the sleeve 2 moves to the leftmost end of the cavity of the cylinder 1 and cannot move further, as the hydraulic oil continues to push, the No. 2 sealing plate 63 moves to the left relative to the No. 1 sealing plate 61. At the same time, the connecting rod 53 is also driven by the No. 2 sealing plate 63 to move to the left relative to the push piece 51 at the right end of the sleeve 2, thereby driving the block 56 at the right end of the sleeve 2 to slide along the rectangular groove 54 to the groove 55 opened on the cylinder 1 through the rectangular frame 59 at the right end of the sleeve 2. At this time, the connecting spring 652 is in a normal state, so that the right block 56 can be stabilized in the groove 55 opened on the cylinder 1.

[0038] In this state, since the No. 1 sealing plate 61 and the No. 2 sealing plate 63 are misaligned left and right, the hydraulic oil can enter the sleeve 2 along the fan-shaped notch 64, and the hydraulic oil entering the sleeve 2 pushes the push plate 7 and the push piece 51 in the sleeve 2 and the piston rod 4 to move synchronously to the left. When the push piece 51 in the sleeve 2 moves to the leftmost side of the sleeve 2 cavity, it cannot move further. As the hydraulic oil continues to flow in, the push plate 7 and the connecting rod 53 are pushed to move synchronously to the left relative to the push piece 51 in the sleeve 2, and then the block 56 in the sleeve 2 is driven through the rectangular frame 59 to enter the slot 55 opened on the sleeve 2. When the two blocks 56 are located in the slot 55 on the sleeve 2, the piston rod 4 and the sleeve 2 can be locked, thereby reducing the pressure borne by the valve in the external hydraulic system, thereby extending its service life.

[0039] See also Figure 8 The cleaning unit 8 connected to the sleeve 2 includes a collecting seat 81, which is rotatably sleeved on the right end of the sleeve 2. The collecting seat 81 is fixedly connected to the cylinder 1 through a torsion spring 82. The left end of the sleeve 2 is fixedly connected to a scraping seat 83, and a decontamination component 84 is commonly provided on the collecting seat 81 and the scraping seat 83.

[0040] See also Figure 4 and Figure 8 The decontamination assembly 84 includes an inclined groove 841. The side wall of the collecting seat 81 is evenly provided with a plurality of inclined grooves 841 along the circumferential direction. The right ends of the inclined grooves 841 are commonly connected with an annular groove 842. The right end surface of the scraper seat 83 is evenly fixedly connected with a plurality of elastic scrapers 843 along the circumferential direction. The push member 51 in the cylinder 1 is connected with a rotating module 844 that cooperates with the scraper seat 83.

[0041] See also Figure 4 and Figure 5 The rotating module 844 includes a spiral groove 8441. The inner wall of the cylinder 1 is provided with a spiral groove 8441. The side wall of the push member 51 is fixedly connected with a slider 8442. The slider 8442 is slidably connected in the spiral groove 8441, and the slider 8442 and the spiral groove 8441 are sealed. The cleaning unit 8 connected to the piston rod 4 has the same structure as the cleaning unit 8 connected to the sleeve 2, and the blocking block 71 is slidably connected in the spiral groove 8441.

[0042] During specific operation, when it is necessary to retract the sleeve 2 and the piston rod 4, on the one hand, hydraulic oil is extracted from the No. 1 oil port 31 through the external hydraulic system, and on the other hand, hydraulic oil is introduced into the No. 2 oil port 32 through the external hydraulic system. The introduced hydraulic oil enters the sleeve 2 along the oil delivery groove 33, and then fills the cylindrical groove 34 along the oil passage 35. At this time, under the push of the hydraulic oil, the push plate 7 and the connecting rod 53 move to the right and reset, and the rectangular frame 59 in the sleeve 2 drives the block 56 in the sleeve 2 to slide out of the card slot 55 on the sleeve 2, releasing the locking of the sleeve 2. The push piece 51 is locked, and then as the hydraulic oil continues to flow in, the push piece 51 in the sleeve 2 is driven to move to the right together with the piston rod 4 through the push plate 7 and retracted into the sleeve 2. When the push piece 51 in the sleeve 2 moves to the rightmost end of the hollow cavity in the sleeve 2, the No. 2 sealing plate 63 is pushed to be assembled with the No. 1 sealing plate 61 through the push plate 7. At this time, the hydraulic oil is stopped from being introduced from the No. 2 oil port 32. Then, as the external hydraulic system draws hydraulic oil from the No. 2 oil port 32, the sleeve 2 is driven to move to the right through the push piece 51 at the right end of the sleeve and is recovered into the cylinder 1.

[0043] The operating principles of the two cleaning units 8 are the same. Taking the operating process of the cleaning unit 8 on the piston rod 4 as an example, when the slider 8442 slides along the threaded groove, it drives the piston rod 4 to rotate synchronously, and then the impurities contaminated on the side wall of the piston rod 4 will be collected in the inclined groove 841 located on the outer wall of the piston rod 4 and opened on the outer wall of the collecting seat 81. In the final stage of contraction of the piston rod 4, the elastic scraper 843 will enter the corresponding inclined groove 841 and drive the collecting seat 81 to rotate synchronously during the sliding process along the inclined groove 841. At this time, the torsion spring 82 will twist and accumulate force. As the elastic scraper 843 continues to move to the right, it will push the impurities in the inclined groove 841 into the annular groove 842. Due to the loss of the restriction of the inclined groove 841, the collecting seat 81 rotates and resets under the drive of the torsion spring 82, and the centrifugal force generated will cause the impurities to be separated from the annular groove 842, thereby achieving the cleaning effect.

[0044] See also Figure 3 and Figure 7 The connecting unit 9 includes a connecting tube 91, which is a cylindrical cavity structure. The right end of the connecting tube 91 is fixedly connected to the left end of the piston rod 4. The left end of the connecting tube 91 is slidably connected with a sliding rod 92. The left end of the sliding rod 92 is fixedly connected with a connecting plate 93. The connecting plate 93 and the sliding rod 92 are jointly connected with a shock absorbing assembly. The left end surface of the connecting plate 93 and the right end of the cylinder 1 are fixedly connected with a connecting piece 95. The shock absorbing assembly includes an annular plate 941. The side wall of the connecting tube 91 is fixedly sleeved with an annular plate 941. The annular plate 941 and the connecting plate 93 are fixedly connected by a shock absorbing spring 942.

[0045] During specific operation, after the connecting piece 95 is connected to the external heavy object to be lifted, when the gravity of the heavy object suddenly decreases or increases, the shock absorbing spring 942 will change accordingly, and the slide rod 92 will expand and contract relative to the connecting tube 91 to absorb the vibration, thereby avoiding the external force from being transmitted to the piston rod 4.

[0046] In the description of the embodiments of the present invention, it should be noted that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "oil level", "top", "bottom", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present invention. In addition, in the description of the present invention, unless otherwise specified, "multiple", "multiple roots", and "multiple groups" mean two or more.

[0047] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] The embodiments of this specific implementation mode are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be included in the protection scope of the present invention. The preferred embodiments of the invention are not intended to limit the protection scope of the present invention. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A new type of multi-stage hydraulic cylinder, characterized in that: The invention comprises a cylinder (1) and a sleeve (2), wherein the cylinder (1) and the sleeve (2) are both cylindrical cavity structures, the sleeve (2) is slidably connected to the left end of the cylinder (1), a retracting unit (3) is provided on the cylinder (1) and the sleeve (2), the left end of the sleeve (2) is slidably connected to a piston rod (4), and the right ends of the piston rod (4) and the sleeve (2) are both connected to a pushing unit (5); The push unit (5) connected to the right end of the sleeve (2) comprises a push piece (51), the push piece (51) is fixedly connected to the right end of the sleeve (2), a circular groove (52) is provided on the second push piece (51) to pass through the left and right sides, a linkage rod (53) is arranged in the circular groove (52), a rectangular groove (54) is symmetrically provided on the side wall of the push piece (51), a clamping groove (55) corresponding to the rectangular groove (54) is provided on the inner wall of the cylinder (1), a clamping block (56) is slidably connected in the rectangular groove (54), the end of the clamping block (56) close to the linkage rod (53) is fixedly connected to a first hinge seat (57), the side wall of the linkage rod (53) is fixedly connected to a second hinge seat (58) corresponding to the first hinge seat (57), and a rectangular frame (59) is hingedly connected between the corresponding first hinge seat (57) and the second hinge seat (58); The pushing unit (5) connected to the right end of the piston rod (4) has the same structure as the pushing unit (5) connected to the right end of the sleeve (2); The connecting rod (53) in the cylinder (1) is connected to an opening and closing unit (6); the right end of the connecting rod (53) in the sleeve (2) is rotatably connected to a push plate (7); the sleeve (2) and the piston rod (4) are both connected to a cleaning unit (8); a sealing block (71) matching the cleaning unit (8) is fixedly connected to the side wall of the push plate (7); and the left end of the piston rod (4) is connected to a connecting unit (9).

2. A novel multi-stage hydraulic cylinder according to claim 1, characterized in that: The retractable unit (3) comprises a first oil port (31), a right end of the side wall of the cylinder (1) having the first oil port (31) extending therethrough, a left end of the side wall of the cylinder (1) having a second oil port (32) fixedly provided thereon, an oil delivery groove (33) provided in the sleeve (2), the right end of the oil delivery groove (33) cooperating with the second oil port (32), the left end of the oil delivery groove (33) communicating with the cavity in the sleeve (2), a columnar groove (34) provided on the right end face of the piston rod (4), and an oil through port (35) communicating with the columnar groove (34) provided on the side wall of the piston rod (4).

3. A novel multi-stage hydraulic cylinder according to claim 1, characterized in that: The opening and closing unit (6) comprises a No. 1 sealing plate (61), which is located in the cavity of the sleeve (2) and is fixedly connected to the pusher (51). The No. 1 sealing plate (61) is provided with through grooves (62) matching the circular grooves (52) on the left and right sides. The left end of the linkage rod (53) is fixedly connected to the No. 2 sealing plate (63). The left end surfaces of the No. 1 sealing plate (61) and the No. 2 sealing plate (63) are uniformly provided with a plurality of fan-shaped notches (64) along the circumferential direction. The fan-shaped notches (64) on the No. 1 sealing plate (61) and the fan-shaped notches (64) on the No. 2 sealing plate (63) are staggered. The right end of the linkage rod (53) is connected to a retaining assembly (65).

4. A novel multi-stage hydraulic cylinder according to claim 3, characterized in that: The retaining assembly (65) comprises a circular plate (651), wherein the circular plate (651) is fixedly connected to the right end of the linkage rod (53), and the circular plate (651) and the pusher (51) are fixedly connected via a connecting spring (652).

5. A novel multi-stage hydraulic cylinder according to claim 1, characterized in that: The cleaning unit (8) connected to the sleeve (2) comprises a collecting seat (81), the collecting seat (81) is rotatably sleeved on the right end of the sleeve (2), the collecting seat (81) is fixedly connected to the cylinder (1) via a torsion spring (82), the left end of the sleeve (2) is fixedly connected to a dirt scraping seat (83), and a dirt removal component (84) is commonly provided on the collecting seat (81) and the dirt scraping seat (83).

6. A novel multi-stage hydraulic cylinder according to claim 5, characterized in that: The decontamination assembly (84) comprises an inclined groove (841), a plurality of inclined grooves (841) are uniformly provided on the side wall of the collecting seat (81) along the circumferential direction, the right ends of the inclined grooves (841) are commonly connected to an annular groove (842), a plurality of elastic scrapers (843) are uniformly fixedly connected to the right end surface of the scraping seat (83) along the circumferential direction, and a rotating module (844) matching the scraping seat (83) is connected to the pushing member (51) in the cylinder (1).

7. A novel multi-stage hydraulic cylinder according to claim 6, characterized in that: The rotating module (844) includes a spiral groove (8441), the inner wall of the cylinder (1) is provided with a spiral groove (8441), the side wall of the push member (51) is fixedly connected with a slider (8442), the slider (8442) is slidably connected in the spiral groove (8441), and the slider (8442) and the spiral groove (8441) are sealed, the cleaning unit (8) connected to the piston rod (4) has the same structure as the cleaning unit (8) connected to the sleeve (2), and the blocking block (71) is slidably connected in the spiral groove (8441).

8. A novel multi-stage hydraulic cylinder according to claim 1, characterized in that: The connecting unit (9) comprises a connecting tube (91), the connecting tube (91) is a cylindrical cavity structure, the right end of the connecting tube (91) is fixedly connected to the left end of the piston rod (4), the left end of the connecting tube (91) is slidably connected to a sliding rod (92), the left end of the sliding rod (92) is fixedly connected to a connecting plate (93), the connecting plate (93) and the sliding rod (92) are jointly connected to a shock absorbing assembly, and the left end surface of the connecting plate (93) and the right end of the cylinder (1) are fixedly connected to a connecting piece (95).

9. A novel multi-stage hydraulic cylinder according to claim 8, characterized in that: The shock absorbing assembly comprises an annular plate (941), the side wall of the connecting tube (91) is fixedly sleeved with the annular plate (941), and the annular plate (941) and the connecting plate (93) are fixedly connected via a shock absorbing spring (942).

Images