A multi-stage hydraulic cylinder device used in series

Abstract

The present invention belongs to the technical field of hydraulic cylinders, and in particular relates to a hydraulic cylinder device used in multi-stage series, comprising a plurality of coaxially connected cylinder bodies, a piston cavity is formed inside the cylinder bodies, and a docking hole is opened at the tail end thereof, a docking boss is provided at the head end of the cylinder body, and a piston hole is formed at the center of the docking boss, a head piston rod is inserted in the cylinder body at the head end, a piston connecting rod is connected to the tail end of the head piston rod in turn, and a sealing piston is provided on both the head piston rod and the piston connecting rod, the docking boss sealing cover at the front end of the plurality of coaxially connected cylinder bodies is combined with a front end cover, and a tail end cover is sealed and inserted in the docking hole opened at the tail end thereof, and an oil pipeline is connected to the cylinder body; the present invention can improve the efficiency of rapid assembly or disassembly of the multi-stage serial hydraulic cylinders, and will not affect the sealing effect between the entire serially connected hydraulic cylinders due to frequent disassembly and assembly of the tail cylinder body.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydraulic cylinders, and in particular relates to a multi-stage hydraulic cylinder device used in series. Background Art

[0002] The function of a hydraulic cylinder is to convert hydraulic energy into mechanical energy for reciprocating linear motion, driving the working mechanism connected to its extension rod to move and perform work. The hydraulic cylinder is the largest and most widely used actuator in hydraulic technology.

[0003] In order to increase the output load of the hydraulic cylinder, the existing method is mostly to connect the cylinder bodies of multiple hydraulic cylinders in series, and then connect multiple piston rods in sequence to form a larger output load. However, it is obvious that due to the connection method between the multiple cylinder bodies and the design of the connecting parts, if it is necessary to add another hydraulic cylinder to the original hydraulic cylinder in series, it is necessary to disassemble the hydraulic cylinder body at the tail end, and then install the corresponding cylinder body of the middle section, and then install the tail end cylinder body accordingly. When it is necessary to disassemble one of the cylinder bodies, it is also necessary to disassemble the tail end cylinder body first, then disassemble the cylinder body of the middle section, and then assemble the tail end cylinder body to the corresponding cylinder body. Obviously, this method of assembling or disassembling multiple hydraulic cylinders in series not only affects the efficiency of their assembly or disassembly, but also affects the sealing effect between the two adjacent cylinder bodies after assembly. Summary of the Invention

[0004] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0005] The present invention is a hydraulic cylinder device used in multi-stage series, comprising a plurality of coaxially connected cylinder bodies, a piston cavity being formed inside the cylinder bodies, and a docking hole being opened at the tail end thereof, a docking boss being provided at the head end of the cylinder body, and a piston hole being formed at the center of the docking boss, a head piston rod being inserted into the cylinder body at the head end, a piston connecting rod being connected to the tail end of the head piston rod in turn, a sealing piston being provided on both the head piston rod and the piston connecting rod, a front end cover being combined with a front end cover on the docking boss sealing cover at the front end of the plurality of coaxially connected cylinder bodies, and a tail end cover being sealed and inserted in the docking hole opened at the tail end thereof, and an oil pipeline being connected to the cylinder body.

[0006] Furthermore, flanges are provided on the outer ring surfaces of the head end and the tail end of the cylinder body, and the flanges between two adjacent cylinder bodies are connected by bolts.

[0007] Furthermore, the docking boss includes a first boss and a second boss, the diameter of the first boss is larger than the diameter of the second boss, and the first boss is located in the docking hole, and the second boss is located in the piston hole, the diameter of the sealing piston is smaller than the diameter of the docking hole, and the sealing assembly is expanded on the docking boss.

[0008] Furthermore, the expansion sealing assembly includes a sac-type expansion ring, a sealing ring, a connecting bend, an arc-shaped sac plate and an elastic arc plate, at least two first annular grooves are formed on the first boss, a second annular groove is formed on the second boss, a sac-type expansion ring is installed in the first annular groove, a sealing ring is installed in the second annular groove, the upper and lower sac-type expansion rings are connected by a plurality of connecting bends, a plurality of bending grooves are provided on the docking boss, and connecting bends are embedded in the bending grooves, at least two annular grooves are provided in the docking hole, and the annular grooves Corresponding to the first annular groove opened on the inserted first boss, an annular groove is opened on the surface of the flange plate, and a plurality of arc-shaped capsule plates and a plurality of elastic arc-shaped plates are installed in the annular groove. The plurality of arc-shaped capsule plates and the plurality of elastic arc-shaped plates are interconnected to form an annular ring. The plurality of arc-shaped capsule plates are connected with the plurality of connecting bends. The thickness of the annular ring is greater than the groove depth of the annular groove. A through hole is opened on the elastic arc plate. The two adjacent flange plates are connected by a plurality of bolts. The screw rods of the bolts are plugged into and matched with the through holes.

[0009] Furthermore, the front end cover includes a front flange and a stepped end cover, the front flange and the stepped end cover are designed to be integrally formed, and the front flange corresponds to the flange plate, and the stepped end cover is sealed and covered on the docking boss at the head of the cylinder body.

[0010] Furthermore, the tail end cover includes a tail flange, a tail boss and a sealing boss. The tail flange and the sealing boss are designed to be integrally formed, and the tail flange corresponds to the flange plate. The structure of the tail boss is the same as that of the docking boss, and the cylindrical seal of the sealing boss is connected to the piston hole opened on the tail boss.

[0011] Furthermore, the head piston rod and the piston connecting rod have the same structure, and the two are connected by an extrusion and fastening assembly, which includes a docking sleeve, an insert block, an arc-shaped push block, a spring member, a sealing ring, a sliding guide tube, a connecting pipe and an external threaded pipe. The tail end of the piston connecting rod is provided with a plug-in hole, and the head end is fixed with a docking sleeve, the docking sleeve and the plug-in hole are plugged into each other, a sliding hole is formed inside the piston connecting rod, and a number of insert blocks are slidably installed on the wall of the docking sleeve, and a number of fastening slots are provided on the wall of the plug-in hole, and a number of the fastening slots correspond to a number of plug holes, and the inner ends of a number of the insert blocks are provided with arc-shaped push blocks, and the inner end faces of the arc-shaped push blocks are connected to the plug holes through spring members. On the wall of the docking sleeve, several arc-shaped push blocks are arranged in a circular ring shape inside the docking sleeve, and the inner diameter of the docking sleeve is larger than the aperture of the sliding hole. A bearing is installed at the bottom of the sealing boss, and a sealing ring is provided on the inner ring of the bearing. A sliding guide tube is sealed and plugged into the sealing ring. A threaded hole is provided at the top end of the sliding guide tube, and an external threaded groove is formed on the outer ring surface of the top. A threaded groove is also provided at the connection between the sliding hole and the plug-in hole. The top of the sliding guide tube is connected to a connecting tube through an external threaded tube, and the two adjacent connecting tubes are also threadedly connected through the external threaded tube and the threaded hole opened at the top. The outer ring surface of the top of the connecting tube is also formed with an external threaded groove that is threadedly connected to the thread groove opened on the sliding hole.

[0012] Furthermore, a secondary piston assembly is provided in the first piston rod, and the secondary piston assembly includes a sliding piston, a sealing sliding plug and a connecting disk. A sliding cavity is formed in the first piston rod, and a sliding piston is slidingly inserted in the sliding cavity. The bottom of the sliding piston is sealed and slidingly connected to the sliding cavity through the sealing sliding plug. The bottom of the sliding piston is connected to a spring part, and the top of the spring part is connected to the connecting disk. A threaded hole is opened at the center of the connecting disk, and the threaded hole is threadedly connected to the outer ring of the top of the connecting pipe.

[0013] Furthermore, the interconnected sliding conduit and connecting pipe together form a guide pipe, the tail of the sliding conduit is connected to a liquid guide hose, and the liquid guide hose is connected to the oil storage system through a valve.

[0014] Furthermore, the two oil pipelines are respectively connected to oil holes provided on the cylinder body, and the two oil pipelines are connected to the oil storage system through a reversing valve.

[0015] The present invention has the following beneficial effects:

[0016] 1. The present invention provides a docking boss at the head end of the cylinder body and a docking hole at the tail end thereof. If it is necessary to add another cylinder body to the cylinder bodies in series, it is only necessary to remove the tail end cover from the cylinder body at the tail end, and then insert the docking boss on the new cylinder body into the docking hole provided on the cylinder body at the tail end, and connect the corresponding piston connecting rods to each other, and then close the tail end cover sealing cover to the tail end of the newly added cylinder body, so that the new cylinder body can be quickly assembled to the multiple cylinder bodies in series, and there is no need to disassemble the tail cylinder body before installing the new cylinder body.

[0017] 2. When it is necessary to reduce the number of cylinder bodies connected in series, it is only necessary to disassemble the rear cylinder body, so that the last cylinder body connected in series after disassembly serves as the rear cylinder body, and then install the rear end cover into the docking hole opened at the rear of the corresponding cylinder body. In this way, multiple cylinder bodies connected in series can be quickly disassembled and reduced, and there is no need to install the disassembled rear cylinder body onto multiple cylinder bodies connected in series. This can improve the efficiency of rapid assembly or disassembly of multi-stage hydraulic cylinders in series, and the sealing effect between the entire hydraulic cylinders in series will not be affected due to frequent disassembly and assembly of the rear cylinder body.

[0018] 3. The present invention provides an expansion sealing assembly on the docking boss. The sealing ring on the second boss plays a first-layer sealing effect, and the expanded and inserted sac-type expansion ring can play a second-layer sealing effect between the docking hole and the first boss. The connected annular ring can play a third-layer sealing effect between the two flanges after being squeezed, thereby further improving the sealing between the cylinder bodies after docking. The annular ring formed by multiple arc-shaped sac plates and multiple elastic arc plates is fixed in the flange by bolts. Therefore, it will not rotate in the flange and affect its sealing effect. At the same time, the expanded and inserted sac-type expansion ring will play an axial limiting role between the docking boss and the cylinder body, preventing the first piston rod or piston connecting rod from axially sliding in the cylinder body, and preventing the docking boss from producing a slight axial slip in the docking hole due to the force of the hydraulic oil in the piston chamber.

[0019] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1It is a schematic diagram of the overall structure of the embodiment disclosed in the present invention;

[0022] Figure 2 This is a diagram showing the matching state of the cylinder body and the piston connecting rod in the disclosed embodiment of the present invention;

[0023] Figure 3 This is a cross-sectional view of the first piston rod of the disclosed embodiment of the present invention;

[0024] Figure 4 This is a cross-sectional view of a cylinder body according to an embodiment of the present invention;

[0025] Figure 5 A cross-sectional view of the tail end cover of the disclosed embodiment of the present invention;

[0026] Figure 6 This is a cross-sectional view of a piston connecting rod according to an embodiment of the present invention.

[0027] In the figure: 1, cylinder body; 101, piston chamber; 102, docking hole; 103, annular groove; 104, flange; 105, annular groove;

[0028] 2. Docking boss; 21. Piston hole; 22. First boss; 23. Second boss; 24. First annular groove; 25. Second annular groove; 26. Bending groove;

[0029] 3. First piston rod; 31. Sliding chamber;

[0030] 4. Piston connecting rod; 41. Sealing piston; 42. Connecting hole; 43. Sliding hole; 44. Fastening slot;

[0031] 5. Expansion sealing assembly; 51. Bladder expansion ring; 52. Sealing ring; 53. Connecting elbow; 54. Arc-shaped bladder plate; 55. Elastic arc-shaped plate;

[0032] 6. Front end cover; 61. Front flange; 62. Stepped end cover;

[0033] 7. Tail end cover; 71. Tail flange; 72. Tail boss; 73. Sealing boss;

[0034] 8. Extrusion fastening assembly; 81. Docking sleeve; 82. Insert block; 83. Arc-shaped push block; 84. Spring member; 85. Sealing ring; 86. Sliding guide tube; 87. Connecting pipe; 88. Externally threaded pipe;

[0035] 9. Secondary piston assembly; 91. Sliding piston; 92. Sealing slide plug; 93. Connecting plate; 94. Liquid guide hose;

[0036] 10. Oil pipeline. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0039] See also Figures 1-6 As shown, the present invention is a hydraulic cylinder device used in multi-stage series, a hydraulic cylinder device used in multi-stage series, characterized in that it comprises a plurality of coaxially connected cylinder bodies 1, a piston cavity 101 is formed inside the cylinder body 1, and a docking hole 102 is opened at the tail end thereof, a docking boss 2 is provided at the head end of the cylinder body 1, and a piston hole 21 is formed at the center of the docking boss 2, a head piston rod 3 is inserted into the cylinder body 1 at the head end, and a piston connecting rod 4 is connected to the tail end of the head piston rod 3 in turn, and a sealing piston 41 is provided on both the head piston rod 3 and the piston connecting rod 4, a sealing piston 41 is provided on each of the head piston rod 3 and the piston connecting rod 4, a front end cover 6 is sealed on the docking boss 2 sealing cover of the front end of the plurality of coaxially connected cylinder bodies 1, and a tail end cover 7 is sealed and inserted in the docking hole 102 opened at the tail end thereof, and an oil pipeline 10 is connected to the cylinder body 1;

[0040] Specifically, the present invention provides a docking boss 2 at the head end of the cylinder body 1, and a docking hole 102 at the tail end thereof. Therefore, when multiple cylinder bodies 1 need to be assembled, the head piston rod 3 is inserted from bottom to top into the piston cavity 101 opened inside the first cylinder body 1, and the sealing piston 41 is slidably and sealedly inserted into the piston cavity 101, and then the docking boss 2 at the head end of the second cylinder body 1 is inserted into the docking hole 102 opened at the tail end of the first cylinder body 1, and the piston hole 21 on the docking boss 2 is aligned with the piston rod 3. The cavity 101 is connected, and at this time the piston connecting rod 4 in the second cylinder body 1 will be connected to the first piston rod 3, and then the cylinder bodies 1 will be plugged in and connected in series in turn, and then the front end cover 6 will be covered on the docking boss 2 at the head of the first cylinder body 1, and the tail end cover 7 will be sealed on the docking hole 102 opened at the tail of the tail cylinder body 1 to achieve sealing of the multiple cylinder bodies 1 in series. If it is necessary to continue to add a cylinder body 1 to the cylinder body 1 in series, at this time, it is only necessary to remove the tail end cover 7 from the tail cylinder body 1 , then insert the docking boss 2 on the new cylinder body 1 into the docking hole 102 opened on the tail cylinder body 1, and the corresponding piston connecting rods 4 are connected to each other, and then the tail end cover 7 is sealed and covered on the tail of the newly added cylinder body 1, so that the new cylinder body 1 can be quickly assembled to the multiple cylinder bodies 1 in series, and there is no need to disassemble the tail cylinder body 1 before installing the new cylinder body 1. When the number of cylinder bodies 1 in series needs to be reduced, only the tail cylinder body 1 needs to be disassembled, so that the disassembly The last cylinder body 1 connected in series is used as the tail cylinder body 1, and then the tail end cover 7 is installed in the docking hole 102 opened at the tail of the corresponding cylinder body 1, so that multiple cylinder bodies 1 connected in series can be quickly disassembled and reduced, and there is no need to install the disassembled tail cylinder body 1 on multiple cylinder bodies 1 in series, thereby improving the efficiency of rapid assembly or disassembly of multi-stage serial hydraulic cylinders, and the sealing effect between the entire serial hydraulic cylinders will not be affected by the frequent disassembly and assembly of the tail cylinder body 1.

[0041] In the design scheme of the present invention, the outer ring surfaces of the head end and the tail end of the cylinder body 1 are both provided with flanges 104. The flanges 104 between two adjacent cylinder bodies 1 are connected by bolts. The docking boss 2 includes a first boss 22 and a second boss 23. The diameter of the first boss 22 is larger than the diameter of the second boss 23, and the first boss 22 is located in the docking hole 102, and the second boss 23 is located in the piston hole 21. The diameter of the sealing piston 41 is smaller than the diameter of the docking hole 102. The expansion sealing assembly 5 is tightened on the docking boss 2.

[0042] Specifically, when two adjacent cylinder bodies 1 are plugged in, when the docking boss 2 is inserted into the docking hole 102, the first boss 22 will be located in the docking hole 102, and the second boss 23 will be inserted into the piston hole 21, so as to seal the bottom of the piston hole 21. After the two adjacent cylinder bodies 1 are docked, the upper and lower flanges 104 that are in contact with each other can be connected and fixed by the cooperation of a number of bolts and nuts, thereby facilitating the fixed connection of the two adjacent docked cylinder bodies 1 together. When the docking boss 2 is inserted into the docking hole 102, the expansion sealing assembly 5 can expand and seal the connection between the two adjacent cylinder bodies 1 to prevent the hydraulic oil entering the piston cavity 101 from leaking.

[0043] In the design scheme of the present invention, the expansion sealing assembly 5 includes a sac-type expansion ring 51, a sealing ring 52, a connecting bend 53, an arc-shaped sac plate 54 and an elastic arc plate 55. At least two first annular grooves 24 are formed on the first boss 22, and a second annular groove 25 is formed on the second boss 23. The sac-type expansion ring 51 is installed in the first annular groove 24, and the sealing ring 52 is installed in the second annular groove 25. The upper and lower sac-type expansion rings 51 are connected by multiple connecting bends 53. A plurality of bending grooves 26 are provided on the docking boss 2, and a connecting bend 53 is embedded in the bending groove 26. At least two annular grooves 10 are provided in the docking hole 102. 3, and the annular groove 103 corresponds to the first annular groove 24 opened on the inserted first boss 22, an annular groove 105 is opened on the surface of the flange 104, and a plurality of arc-shaped capsule plates 54 and a plurality of elastic arc plates 55 are installed in the annular groove 105, the plurality of arc-shaped capsule plates 54 and the plurality of elastic arc plates 55 are connected to each other to form an annular ring, the plurality of arc-shaped capsule plates 54 are connected to the plurality of connecting elbows 53, the thickness of the annular ring is greater than the groove depth of the annular groove 105, the elastic arc plate 55 is provided with a through hole, and the two adjacent flanges 104 are connected by a plurality of bolts, and the screws of the bolts are plugged into the through holes;

[0044] Specifically, when the docking boss 2 on the top of the cylinder body 1 needs to be inserted into the docking hole 102, at least two sac-shaped expansion rings 51 are first sleeved in sequence into the first annular groove 24 opened on the first boss 22, and at the same time, at least six connecting bends 53 arranged in a circumferential array are bent in sequence to be inserted into the bending groove 26, and at the same time, the arc-shaped sac plate 54 connected to the connecting bend 53 is embedded in the annular groove 105, and the through hole opened on the elastic arc plate 55 is aligned with the hole on the flange 104, and then the sealing ring 52 is sleeved into the second annular groove 25 opened on the second boss 23. Therefore, when the docking After the boss 2 is inserted into the docking hole 102, the sealing ring 52 will be sealed and fitted to the cavity wall connecting the docking hole 102 and the piston cavity 101, and at least two sac-type expansion rings 51 will be aligned with the annular groove 103, and the arc-shaped sac plate 54 and the elastic arc plate 55 forming an annular ring will be located in the annular groove 105 of the upper and lower flanges 104. As the multiple bolts and nuts on the flanges 104 are tightened, the upper and lower flanges 104 are pressed against each other. At this time, the multiple arc-shaped sac plates 54 will be compressed, so that the gas inside them will enter the at least two sac-type expansion rings 51 through the multiple connecting bends 53. Since the sac-shaped expansion ring 51 corresponds to the annular groove 103, and the cross-section of the annular groove 103 is trumpet-shaped, the sac-shaped expansion ring 51 will expand into the annular groove 103, so that the expanded sac-shaped expansion ring 51 can be sealed and snapped into the connection between the docking hole 102 and the first boss 22, so that the sealing ring 52 on the second boss 23 plays a first layer of sealing effect, and the expanded and snapped sac-shaped expansion ring 51 can play a second layer of sealing effect between the docking hole 102 and the first boss 22, and the connected annular ring can play a third layer of sealing effect between the two flanges 104 after being squeezed. , thereby further improving the sealing between the cylinder bodies 1 after docking, and the annular ring formed by multiple arc-shaped bag plates 54 and multiple elastic arc-shaped plates 55 is fixed in the flange 104 by bolts. Therefore, it will not rotate in the flange 104 and affect its sealing effect. At the same time, the expanded and stuck bag-shaped expansion ring 51 will play an axial limiting role between the docking boss 2 and the cylinder body 1, preventing the head piston rod 3 or the piston connecting rod 4 from axially sliding in the cylinder body 1. The phenomenon of the docking boss 2 producing a small axial slip in the docking hole 102 due to the force of the hydraulic oil in the piston chamber 101 causes the docking boss 2 to have an axial slip.

[0045] In the design scheme of the present invention, the front end cover 6 includes a front flange 61 and a stepped end cover 62, the front flange 61 and the stepped end cover 62 are designed as an integral part, and the front flange 61 corresponds to the flange plate 104, and the stepped end cover 62 is sealed and covered on the docking boss 2 at the head of the cylinder body 1, and the tail end cover 7 includes a tail flange 71, a tail boss 72 and a sealing boss 73, the tail flange 71 and the sealing boss 73 are designed as an integral part, and the tail flange 71 corresponds to the flange plate 104, the structure of the tail boss 72 is the same as that of the docking boss 2, and the cylindrical sealing of the sealing boss 73 is connected to the piston hole 21 opened on the tail boss 72;

[0046] Specifically, the stepped end cover 62 will be sealed and covered on the docking boss 2 at the head end of the first cylinder body 1 through the front flange 61, and the front flange 61 and the flange 104 on the head end of the cylinder body 1 are connected by a number of bolts to achieve sealing of the head end of the first cylinder body 1, and the tail end cover 7 is sealed and inserted into the docking hole 102 opened at the tail end of the tail cylinder body 1 through the cooperation of the tail flange 71 and the sealing boss 73. Since the structure of the tail boss 72 is the same as that of the docking boss 2, the tail end cover 7 can be sealed and inserted into the docking hole 102 opened at the tail end of any cylinder body 1, and the tail flange 71 is connected to the flange 104 at the tail end of the cylinder body 1 through a number of bolts, and then cooperates with the expansion sealing assembly 5 to achieve rapid sealing of the docking hole 102 opened at the tail end of the series-connected tail cylinder body 1.

[0047] In the design scheme of the present invention, the head piston rod 3 and the piston connecting rod 4 have the same structure, and the two are connected by an extrusion and fastening assembly 8, which includes a docking sleeve 81, an insert block 82, an arc-shaped push block 83, a spring member 84, a sealing ring 85, a sliding guide tube 86, a connecting pipe 87 and an external threaded tube 88. The tail end of the piston connecting rod 4 is provided with a plug hole 42, and the head end is fixed with a docking sleeve 81. The docking sleeve 81 and the plug hole 42 are plugged into each other. A sliding hole 43 is formed inside the piston connecting rod 4. Several plug blocks 82 are slidably installed on the wall of the docking sleeve 81. Several fastening slots 44 are provided on the wall of the plug hole 42. Several of the fastening slots 44 correspond to several sockets. The inner ends of several of the plug blocks 82 are provided with arc-shaped push blocks 83. The inner end faces of the arc-shaped push blocks 83 are through-holes. The spring member 84 is connected to the wall of the docking sleeve 81, and several arc-shaped push blocks 83 are formed into a circular ring inside the docking sleeve 81, and the inner diameter of the docking sleeve 81 is larger than the aperture of the sliding hole 43. A bearing is installed at the bottom of the sealing boss 73, and a sealing ring 85 is provided on the inner ring of the bearing. A sliding guide tube 86 is sealed and inserted in the sealing ring 85. The top of the sliding guide tube 86 is provided with a threaded hole, and an external thread groove is formed on the outer ring surface of the top. The connection between the sliding hole 43 and the plug hole 42 is also provided with a thread groove. The top of the sliding guide tube 86 is connected to a connecting tube 87 through an external threaded tube 88. The two adjacent connecting tubes 87 are also threadedly connected to each other through the external threaded tube 88 and the threaded hole provided on the top. The top outer ring surface of the connecting tube 87 is also formed with an external thread groove that is threadedly connected to the thread groove provided on the sliding hole 43.

[0048] Specifically, when multiple cylinder bodies 1 are connected to each other, the docking sleeve 81 at the head of the piston connecting rod 4 will be inserted into the plug hole 42 opened at the tail of the head piston rod 3, and the multiple plug blocks 82 of the circumferential array will be aligned with the multiple buckling slots 44 opened in the circumferential array. Then, as needed, multiple connecting pipes 87 will be connected in sequence through the external threaded pipe 88, and then the connected multiple connecting pipes 87 will be threadedly connected to the head end of the sliding guide tube 86. At this time, the connected connecting pipes 87 and the sliding guide tube 86 will be inserted into the sliding hole 43 from bottom to top. When the head end of the first connecting tube 87 contacts the multiple arc-shaped push blocks 83 of the circumferential array, since the inner side surface of the bottom end of the arc-shaped push block 83 is designed with an arc angle, and the head end of the connecting tube 87 has a rounded corner, as the connecting tube 87 is continuously inserted, the connecting tube 87 will squeeze the multiple arc-shaped push blocks 83, causing them to slide toward the inner wall of the docking sleeve 81, and the spring member 84 connected to the arc-shaped push block 83 will be compressed, and then the arc-shaped push block 83 will push the insert block 82 to slide and insert into the corresponding buckle slot 44, thereby achieving Now the upper and lower piston connecting rods 4 or the head piston rod 3 and the piston connecting rod 4 are stably and quickly connected. When the external thread groove of the outer ring surface of the head end of the connecting tube 87 corresponds to the thread groove on the sliding hole 43 in the middle piston connecting rod 4, it is necessary to rotate the sliding guide tube 86 so that the external thread groove on the first connecting tube 87 passes over the thread groove. When the head end of the first connecting tube 87 enters the head piston rod 3, the sliding guide tube 86 is rotated so that the outer ring surface of the head end of multiple connecting tubes 87 corresponds to the thread groove on the corresponding sliding hole 43. The sliding guide 86 is connected by a thread, and the head end of the sliding guide 86 is also threadedly connected to the sliding hole 43 in the piston connecting rod 4 at the tail end, which can achieve the purpose of blocking the sliding hole 43 on the last piston connecting rod 4, thereby facilitating the hidden and stable connection of the upper and lower piston connecting rods 4 from the inside. When the connected head piston rod 3 and piston connecting rod 4 slide in the multiple cylinder bodies 1, the sliding guide 86 will slide in a sealed manner in the sealing ring 85, so that it will not interfere with the normal output load of the multiple piston connecting rods 4 and the head piston rod 3 connected to each other;When it is necessary to add a cylinder body 1 and a corresponding piston connecting rod 4 structure, the bolts on the tail flange 71 are first removed, and then the sliding guide 86 is rotated to remove it from the connected connecting pipe 87, so that the tail end cover 7 is removed from the tail cylinder body 1, and then the docking boss 2 on the new cylinder body 1 is inserted into the docking hole 102, and the piston connecting rod 4 is inserted into the corresponding plug hole 42, and then the new connecting pipe 87 is connected to the head end of the sliding guide 86, and then the tail end cover 7 is inserted into the docking hole 102 opened at the tail of the new cylinder body 1. At this time, the newly connected connecting pipe 87 will be inserted into the sliding hole 43 opened inside the new piston connecting rod 4, and the multiple arc-shaped push blocks 83 will be squeezed and pushed, so that the new piston connecting rod 4 is stably and quickly connected to the previous piston connecting rod 4, and then the sliding guide 86 is rotated to make the new connecting pipe 87 They are interconnected with the connecting pipe 87 above, making it easy to quickly add another hydraulic cylinder to the series hydraulic cylinders, further increasing the output load of the series hydraulic cylinders. When the cylinder body 1 needs to be reduced, the flange 104 on the tail end cover 7 is removed, and then the sliding guide 86 needs to be rotated to drive the multiple connecting pipes 87 to simultaneously disengage from the insertion holes 42. At this time, the multiple arc-shaped push blocks 83 drive the insert blocks 82 to disengage from the snap-fit ​​slots 44 under the elastic recovery of the spring member 84, thereby disconnecting the docking sleeve 81 on the piston connecting rod 4 from the insertion hole 42. Then, when the cylinder body 1 is removed, the corresponding piston connecting rod 4 will be synchronously disengaged, and then the corresponding connecting pipe 87 is removed. Then, the tail end cover 7 is sealed and closed to the tail end of the cylinder body 1 that has been disassembled in series, thereby facilitating the disassembly and reduction of the multiple cylinder bodies 1 in series.

[0049] In the design of the present invention, a secondary piston assembly 9 is provided in the first piston rod 3, and the secondary piston assembly 9 includes a sliding piston 91, a sealing sliding plug 92 and a connecting disk 93. A sliding cavity 31 is formed in the first piston rod 3, and the sliding piston 91 is slidingly inserted in the sliding cavity 31. The bottom of the sliding piston 91 is sealed and slidingly connected to the sliding cavity 31 through the sealing sliding plug 92. The bottom of the sliding piston 91 is connected to a spring member 84, and the top of the spring member 84 is connected to the connecting disk 93. A threaded hole is opened at the center of the connecting disk 93, and the threaded hole is threadedly connected to the outer ring of the top of the connecting pipe 87.

[0050] Specifically, when it is necessary to increase the output length of the head piston rod 3, and thus increase the use range of the multi-stage series hydraulic cylinder, the sliding piston 91 is inserted into the sliding cavity 31, and the sealing sliding plug 92 is slidably sealed in the sliding cavity 31. When the connecting plate 93 slides to the bottom of the sliding cavity 31, the threaded hole on the connecting plate 93 is aligned with the sliding hole 43, and then the outer ring surface of the head end of the connecting pipe 87 is threadedly connected to the threaded hole of the connecting plate 93, which is convenient for passing through the connecting plate 93 and the spring member. 84 fixes the sliding piston 91, and then introduces the medium between the sealing sliding plug 92 and the connecting plate 93 through the connecting pipe 87 and the sliding guide tube 86, so that it can push the sliding piston 91 to extend out of the sliding chamber 31, thereby facilitating the increase of the stroke length of the head piston rod 3, thereby increasing the use range of the hydraulic cylinder device used in multi-stage series, and extracting the medium in the sliding chamber 31. The spring part 84 on the connecting plate 93 will pull the sliding piston 91 back into the sliding chamber 31 under its own elastic restoring force.

[0051] In the design scheme of the present invention, the interconnected sliding conduit 86 and connecting tube 87 together form a guide tube, and the tail end of the sliding conduit 86 is connected to a liquid guide hose 94, and the liquid guide hose 94 is connected to the oil storage system through a valve; specifically, the liquid guide hose 94 can inject hydraulic oil into the cavity formed between the sealing slide 92 and the connecting disk 93 through the sliding conduit 86 and the connecting tube 87, thereby facilitating the pushing of the sliding piston 91 to extend or retract from the head piston rod 3.

[0052] In the design scheme of the present invention, the two oil pipelines 10 are respectively connected to the oil holes opened on the cylinder body 1, and the two oil pipelines 10 are connected to the oil storage system through a reversing valve; specifically, the two oil pipelines 10 are connected to the oil holes opened on the outer ring surface of the head and tail ends of the cylinder body 1, so that they will not affect the normal sliding work of the head piston rod 3 or the piston connecting rod 4 in the cylinder body 1.

[0053] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0054] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A multi-stage hydraulic cylinder device used in series, characterized in that: The invention comprises a plurality of coaxially connected cylinder bodies (1), wherein a piston cavity (101) is formed inside the cylinder body (1), and a docking hole (102) is opened at the rear end thereof, a docking boss (2) is provided at the front end of the cylinder body (1), and a piston hole (21) is formed at the center of the docking boss (2), a head piston rod (3) is inserted into the cylinder body (1) at the front end, and a piston connecting rod (4) is connected to the rear end of the head piston rod (3) in turn, and a sealing piston (41) is provided on both the head piston rod (3) and the piston connecting rod (4), and a front end cover (6) is combined with a sealing cover of the docking boss (2) at the front end of the plurality of coaxially connected cylinder bodies (1), and a tail end cover (7) is sealed and inserted into the docking hole (102) opened at the rear end thereof, and an oil pipeline (10) is connected to the cylinder body (1); The outer ring surfaces of the head end and the tail end of the cylinder body (1) are both provided with flanges (104), and the flanges (104) between two adjacent cylinder bodies (1) are connected by bolts; The docking boss (2) comprises a first boss (22) and a second boss (23), the diameter of the first boss (22) is larger than the diameter of the second boss (23), the first boss (22) is located in the docking hole (102), and the second boss (23) is located in the piston hole (21), the diameter of the sealing piston (41) is smaller than the diameter of the docking hole (102), and an expansion sealing assembly (5) is provided on the docking boss (2); The expansion sealing assembly (5) includes a sac-type expansion ring (51), a sealing ring (52), a connecting bend (53), an arc-shaped sac plate (54) and an elastic arc plate (55). At least two first annular grooves (24) are formed on the first boss (22), and a second annular groove (25) is formed on the second boss (23). The sac-type expansion ring (51) is installed in the first annular groove (24), and the sealing ring (52) is installed in the second annular groove (25). The upper and lower sac-type expansion rings (51) are connected through a plurality of connecting bends (53). The docking boss (2) is provided with a plurality of bending grooves (26), and the connecting bends (53) are embedded in the bending grooves (26). The docking hole (102) is provided with a plurality of connecting bends (53). At least two annular grooves (103) are provided, and the annular grooves (103) correspond to the first annular grooves (24) provided on the inserted first boss (22); an annular groove (105) is provided on the surface of the flange (104), and a plurality of arc-shaped capsule plates (54) and a plurality of elastic arc-shaped plates (55) are installed in the annular groove (105); the plurality of arc-shaped capsule plates (54) and the plurality of elastic arc-shaped plates (55) are connected to each other to form an annular ring; the plurality of arc-shaped capsule plates (54) are connected to the plurality of connecting bends (53); the thickness of the annular ring is greater than the groove depth of the annular groove (105); a through hole is provided on the elastic arc plate (55); the screw rod of the bolt is plugged into and matched with the through hole.

2. A multi-stage tandem hydraulic cylinder device according to claim 1, characterized in that: The front end cover (6) includes a front flange (61) and a stepped end cover (62), wherein the front flange (61) and the stepped end cover (62) are integrally formed, and the front flange (61) corresponds to the flange plate (104), and the stepped end cover (62) is sealed and covered on the docking boss (2) at the head of the cylinder body (1).

3. The multi-stage tandem hydraulic cylinder device according to claim 1, characterized in that: The tail end cover (7) includes a tail flange (71), a tail boss (72) and a sealing boss (73). The tail flange (71) and the sealing boss (73) are designed to be integrally formed, and the tail flange (71) corresponds to the flange plate (104). The structure of the tail boss (72) is the same as that of the docking boss (2). The cylindrical seal of the sealing boss (73) is connected to the piston hole (21) opened on the tail boss (72).

4. A multi-stage tandem hydraulic cylinder device according to claim 3, characterized in that: The head piston rod (3) and the piston connecting rod (4) have the same structure, and the two are connected by an extrusion fastening assembly (8), the extrusion fastening assembly (8) comprising a docking sleeve (81), an inserting block (82), an arc-shaped push block (83), a spring member (84), a sealing ring (85), a sliding guide tube (86), a connecting pipe (87) and an external threaded pipe (88), the tail end of the piston connecting rod (4) is provided with a plug hole (42), and the head end thereof is fixedly provided with a docking sleeve (81), The docking sleeve (81) and the plug hole (42) are plugged into each other, a sliding hole (43) is formed inside the piston connecting rod (4), and a plurality of plug blocks (82) are slidably installed on the wall of the docking sleeve (81), and a plurality of buckling slots (44) are opened on the hole wall of the plug hole (42), and a plurality of the buckling slots (44) correspond to a plurality of plug holes, and the inner ends of the plurality of the plug blocks (82) are all provided with arc-shaped push blocks (83), and the inner end surfaces of the arc-shaped push blocks (83) are The plurality of arc-shaped push blocks (83) are connected to the wall of the docking sleeve (81) through a spring member (84), and are arranged in a circular ring shape in the docking sleeve (81). The inner diameter of the docking sleeve (81) is larger than the aperture of the sliding hole (43). A bearing is installed at the bottom of the sealing boss (73), and a sealing ring (85) is provided on the inner ring of the bearing. A sliding guide tube (86) is sealed and inserted in the sealing ring (85). A threaded hole is provided at the top end of the sliding guide tube (86). An external thread groove is formed on the outer ring surface of the top thereof, and a thread groove is also formed at the connection point between the sliding hole (43) and the plug hole (42). The top of the sliding guide tube (86) is connected to the connecting tube (87) through an external threaded tube (88), and the two adjacent connecting tubes (87) are also threadedly connected to the threaded hole opened on the top thereof through the external threaded tube (88). The top outer ring surface of the connecting tube (87) is also formed with an external thread groove that is threadedly connected to the thread groove opened on the sliding hole (43).

5. The multi-stage tandem hydraulic cylinder device according to claim 4, characterized in that: A secondary piston assembly (9) is provided in the first piston rod (3), and the secondary piston assembly (9) includes a sliding piston (91), a sealing sliding plug (92) and a connecting disk (93). A sliding cavity (31) is formed in the first piston rod (3), and a sliding piston (91) is slidingly inserted in the sliding cavity (31). The bottom of the sliding piston (91) is sealingly and slidingly connected to the sliding cavity (31) through the sealing sliding plug (92). The bottom of the sliding piston (91) is connected to a spring member (84), and the top of the spring member (84) is connected to the connecting disk (93). A threaded hole is opened at the center of the connecting disk (93), and the threaded hole is threadedly connected to the outer ring of the top of the connecting pipe (87).

6. A multi-stage tandem hydraulic cylinder device according to claim 5, characterized in that: The interconnected sliding conduit (86) and connecting pipe (87) together form a flow guide pipe. The tail of the sliding conduit (86) is connected to a liquid guide hose (94), and the liquid guide hose (94) is connected to the oil storage system through a valve.

7. The multi-stage tandem hydraulic cylinder device according to claim 1, characterized in that: The two oil pipelines (10) are respectively connected to oil holes provided on the cylinder body (1), and the two oil pipelines (10) are connected to the oil storage system through a reversing valve.

Images