Connecting structure of hollow piston rod and piston for hydraulic cylinder

Abstract

The utility model relates to the technical field of hydraulic cylinders, and discloses a connecting structure of a hollow piston rod and a piston for a hydraulic cylinder, which comprises a middle body, the piston rod and a piston body, a containing cavity with an opening at the tail end and used for containing the piston rod is fixedly arranged in the piston body, and two positioning blocks for limiting the angle of the piston rod are arranged on the inner end face of the containing cavity. An annular locking groove is formed in the piston rod, a set of threaded locking holes are formed in the annular locking groove, each threaded locking hole is provided with a fastening bolt for limiting the position of the piston rod in the containing cavity, the end of the piston rod is in threaded connection with the middle body, and the middle body is tightly attached to the containing cavity. When the piston is used, the piston rod is in threaded connection with the middle body, the middle body conducts multiple sealing on the connecting position of the through cavity and the containing cavity, through the arrangement of the stop ring, on one hand, the relative position of the piston rod and the middle body can be effectively limited, and on the other hand, the sealing degree in the through cavity and the coaxiality of the piston rod and the piston body can be effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic cylinders, and more specifically to a connecting structure of a hollow piston rod and a piston for a hydraulic cylinder. Background Art

[0002] The common connection methods between the piston rod and the piston of a hydraulic cylinder include: threaded connection, welding, keying, etc. There is also a structure in which the piston rod and the piston are an integrated structure.

[0003] In the prior art, the patent document with publication number CN219242345U discloses a piston rod and piston connection structure, including a hemispherical outer groove, a piston, a hemispherical inner groove on the inner ring surface of the piston, a screw hole radially opened on the piston, the screw hole is connected to the inner groove, the inner groove and the outer groove form an annular ball groove, a plurality of steel balls are placed in the annular ball groove, the diameter of the steel balls is the same as the diameter of the ball groove, and a locking screw is arranged in the screw hole to block the screw hole. In the above device, the piston and the piston rod do not need to be processed after assembly, which can improve processing efficiency, save time, and have a simple and compact structure; it is convenient to process, save materials, and reduce costs. However, when the above structure is used, on the one hand, it is not convenient to effectively ensure the sealing of the connection between the piston rod and the piston, and on the other hand, the coaxial retention, connection tightness, and anti-slip and anti-shift efficiency of the piston rod and the piston are relatively limited. Based on this, the utility model provides a connection structure of a hollow piston rod and a piston for a hydraulic cylinder to solve the technical problems raised in the above background technology. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, the utility model provides a connection structure of a hollow piston rod and a piston for a hydraulic cylinder. When the utility model is in use, the piston rod is threadedly connected to an intermediate body, and the intermediate body performs multiple seals on the connection between the through cavity and the receiving cavity. Through the setting of the stop ring, on the one hand, the relative position of the piston rod and the intermediate body can be effectively limited, and on the other hand, the sealing degree in the through cavity and the coaxiality of the piston rod and the piston body can be effectively improved.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a connection structure of a hollow piston rod and a piston for a hydraulic cylinder, comprising an intermediate body, a piston rod and a piston body, a cavity with a tail end opening fixedly provided in the piston body and used to accommodate the piston rod, two positioning blocks for limiting the angle of the piston rod are installed on the inner end surface of the cavity, a ring locking groove is provided on the piston rod, a group of threaded locking holes are provided on the ring locking groove, a fixing bolt for limiting the position of the piston rod in the cavity is installed on each of the threaded locking holes, the end of the piston rod is threadedly connected to the intermediate body, the intermediate body is tightly fitted with the cavity, a stop ring is fixedly installed on the outer periphery of the intermediate body, and the outer diameter of the stop ring is the same as the outer diameter of the piston rod.

[0006] As a preferred technical solution of the utility model, the end of the piston rod is provided with two symmetrically arranged positioning grooves which are engaged with the positioning block, and the axial direction of the threaded lock hole is perpendicular to the axial direction of the piston rod.

[0007] As a preferred technical solution of the utility model, the cavity is provided with a first accommodating section and a second accommodating section from back to front, a chamfered transition section is provided at the connection between the first accommodating section and the second accommodating section, and the radius of the first accommodating section is 1.15 times the radius of the second accommodating section.

[0008] As a preferred technical solution of the utility model, the piston rod is respectively provided with a first piston section adapted to the first accommodating section and a second piston section adapted to the second accommodating section.

[0009] As an optimal technical solution of the utility model, two sealing ring grooves a are provided on the outer periphery of the piston body and corresponding to the rear side of the ring locking groove, and sealing rings a are installed on the two sealing ring grooves a and the ring locking groove, and a sealing ring b is embedded in the inner wall of the cavity.

[0010] As a preferred technical solution of the utility model, a through cavity with openings at both ends is fixedly provided inside the piston rod.

[0011] As a preferred technical solution of the utility model, a V-shaped ring groove adapted to the ring lock groove is fixedly opened on the outer periphery of the piston rod, and the V-shaped ring groove is used to limit the position of the tightening bolt.

[0012] As a preferred technical solution of the utility model, a connecting part adapted to the inner diameter of the through cavity is provided on the intermediate body and at a position corresponding to the rear side of the stop ring, two threaded connecting sections are provided on the outer periphery of the connecting part, and two threaded parts are provided on the through cavity, and the two threaded parts are respectively matched with the two threaded connecting sections, and a ring embedding groove is provided on the connecting part and at a position corresponding to the position between the two threaded connecting sections, and a sealing ring c for sealing the through cavity is installed on the ring embedding groove.

[0013] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0014] When the utility model is in use, the piston rod is threadedly connected to the intermediate body, and the intermediate body performs multiple seals on the connection between the through cavity and the receiving cavity. Through the setting of the stop ring, on the one hand, the relative position of the piston rod and the intermediate body can be effectively limited, and on the other hand, the sealing degree in the through cavity and the coaxiality of the piston rod and the piston body can be effectively improved. Through the setting of the V-shaped ring groove, the position between the piston rod and the piston body can be accurately limited after the fixing bolt is installed, and through the setting of the fixing bolt, the relative displacement rate of the piston rod and the piston body after the fixing bolt is installed can be effectively reduced. Through the setting of the fixing bolt, the quick disassembly and assembly of the connection structure is facilitated and the structural tightness of the connection structure is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a cross-sectional structural schematic diagram of a connection structure between a hollow piston rod and a piston for a hydraulic cylinder of the utility model;

[0016] Figure 2 It is a schematic diagram of the cross-sectional structure of the piston body of the utility model;

[0017] Figure 3 It is a schematic diagram of the cross-sectional structure of the through cavity and the piston rod of the utility model;

[0018] Figure 4 It is a schematic diagram of the cross-sectional structure of the intermediate body and the stop ring of the utility model.

[0019] In the figure: 1, intermediate body; 2, piston rod; 3, piston body; 4, positioning block; 5, ring lock groove; 6, tightening bolt; 7, stop ring; 8, sealing ring groove a; 9, sealing ring a; 10, sealing ring b; 11, through cavity; 12, V-shaped ring groove; 13, connecting part; 14, threaded connecting section; 15, threaded part; 16, sealing ring c; 17, threaded lock hole; 21, positioning groove; 31, accommodating cavity; 311, first accommodating section; 312, second accommodating section. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] like Figures 1 to 4 As shown, the utility model provides a connection structure of a hollow piston rod and a piston for a hydraulic cylinder, comprising an intermediate body 1, a piston rod 2 and a piston body 3, wherein a through cavity 11 with openings at both ends is fixedly provided inside the piston rod 2;

[0022] A cavity 31 with a rear end opening fixedly provided in the piston body 3 and used for accommodating the piston rod 2;

[0023] Two positioning blocks 4 for limiting the angle of the piston rod 2 are installed on the inner end surface of the cavity 31, and two positioning grooves 21 symmetrically arranged and engaged with the positioning blocks 4 are provided at the end of the piston rod 2;

[0024] By setting the positioning block 4 and the positioning groove 21, the angle of the piston rod 2 in the cavity 31 is accurately locked;

[0025] The cavity 31 is provided with a first accommodating section 311 and a second accommodating section 312 from back to front. A chamfered transition section is provided at the connection between the first accommodating section 311 and the second accommodating section 312. The radius of the first accommodating section 311 is 1.15 times the radius of the second accommodating section 312.

[0026] The piston rod 2 is provided with a first piston section adapted to the first accommodating section 311 and a second piston section adapted to the second accommodating section 312 respectively;

[0027] The first accommodating section 311 and the second accommodating section 312 are arranged in a stepped manner, so as to realize a bipolar blocking seal at the connection between the piston rod 2 and the piston body 3, and the bipolar blocking seal can effectively improve the sealing performance at the connection between the piston rod 2 and the piston body 3;

[0028] The piston rod 2 is provided with a ring lock groove 5, and a group of thread lock holes 17 are provided on the ring lock groove 5. Each thread lock hole 17 is installed with a fixing bolt 6 for limiting the position of the piston rod 2 in the cavity 31.

[0029] The axial direction of the threaded lock hole 17 is perpendicular to the axial direction of the piston rod 2;

[0030] Two sealing ring grooves a8 are provided on the outer periphery of the piston body 3 and at positions corresponding to the rear side of the ring lock groove 5. Sealing rings a9 are installed on the two sealing ring grooves a8 and the ring lock groove 5.

[0031] The two sealing rings a9 are provided to effectively ensure the sealing performance of the sliding connection between the piston body 3 and the hydraulic cylinder;

[0032] The end of the piston rod 2 is threadedly connected to the intermediate body 1 , the intermediate body 1 is tightly fitted with the cavity 31 , and a stop ring 7 is fixedly installed on the outer periphery of the intermediate body 1 , and the outer diameter of the stop ring 7 is the same as the outer diameter of the piston rod 2 .

[0033] By setting the stop ring 7, on the one hand, the relative position of the piston rod 2 and the intermediate body 1 can be effectively limited;

[0034] On the other hand, the sealing degree in the through cavity 11 can be effectively improved;

[0035] A sealing ring b10 is embedded in the inner wall of the cavity 31 .

[0036] The outer circumference of the piston rod 2 is fixedly provided with a V-shaped ring groove 12 adapted to the ring lock groove 5, and the V-shaped ring groove 12 is used to define the position of the fastening bolt 6;

[0037] By setting the V-shaped ring groove 12, the position between the piston rod 2 and the piston body 3 can be accurately defined after the fixing bolt 6 is installed, and the relative displacement rate of the piston rod 2 and the piston body 3 can be effectively reduced after the fixing bolt 6 is installed.

[0038] A connecting portion 13 adapted to the inner diameter of the through cavity 11 is provided on the intermediate body 1 and at a position corresponding to the rear side of the stop ring 7. Two threaded connecting sections 14 are provided on the outer periphery of the connecting portion 13. Two threaded portions 15 are provided on the through cavity 11. The two threaded portions 15 are matched with the two threaded connecting sections 14 respectively.

[0039] A ring embedding groove is provided on the connecting portion 13 and at a position corresponding to the position between the two threaded connecting sections 14 , and a sealing ring c16 for sealing the through cavity 11 is installed on the ring embedding groove.

[0040] The working principle and use process of this utility model:

[0041] When in use, the piston rod 2 is threadedly connected to the intermediate body 1, and the intermediate body 1 performs multiple seals on the connection between the through cavity 11 and the accommodating cavity 31. Through the setting of the stop ring 7, on the one hand, the relative position of the piston rod 2 and the intermediate body 1 can be effectively limited, and on the other hand, the sealing degree in the through cavity 11 and the coaxiality of the piston rod 2 and the piston body 3 can be effectively improved. Through the setting of the V-shaped ring groove 12, the position between the piston rod 2 and the piston body 3 can be accurately limited after the fixing bolt 6 is installed, and through the setting of the fixing bolt 6, the relative displacement rate of the piston rod 2 and the piston body 3 after the fixing bolt 6 is installed can be effectively reduced, and through the setting of the fixing bolt 6, the quick disassembly and assembly of the connection structure is facilitated and the structural tightness of the connection structure is improved.

[0042] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A connection structure between a hollow piston rod and a piston for a hydraulic cylinder, comprising an intermediate body (1), a piston rod (2) and a piston body (3), characterized in that: The piston body (3) is fixedly provided with a cavity (31) with a tail end opening for accommodating the piston rod (2). Two positioning blocks (4) for limiting the angle of the piston rod (2) are installed on the inner end surface of the cavity (31). The piston rod (2) is provided with a ring lock groove (5). The ring lock groove (5) is provided with a group of threaded lock holes (17). Each threaded lock hole (17) is installed with a fixing bolt (6) for limiting the position of the piston rod (2) in the cavity (31). The end of the piston rod (2) is threadedly connected to the intermediate body (1). The intermediate body (1) is tightly fitted with the cavity (31). A stop ring (7) is fixedly installed on the outer periphery of the intermediate body (1). The outer diameter of the stop ring (7) is the same as the outer diameter of the piston rod (2).

2. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 1, characterized in that: The end of the piston rod (2) is provided with two symmetrically arranged positioning grooves (21) that are engaged with the positioning block (4), and the axial direction of the threaded lock hole (17) is perpendicular to the axial direction of the piston rod (2).

3. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 2, characterized in that: The cavity (31) is provided with a first accommodating section (311) and a second accommodating section (312) in sequence from back to front, a chamfered transition section is provided at the connection between the first accommodating section (311) and the second accommodating section (312), and the radius of the first accommodating section (311) is 1.15 times the radius of the second accommodating section (312).

4. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 3, characterized in that: The piston rod (2) is respectively provided with a first piston section adapted to the first accommodating section (311) and a second piston section adapted to the second accommodating section (312).

5. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 4, characterized in that: Two sealing ring grooves a (8) are provided on the outer periphery of the piston body (3) and at positions corresponding to the rear side of the ring lock groove (5). A sealing ring a (9) is installed on the two sealing ring grooves a (8) and the ring lock groove (5). A sealing ring b (10) is embedded in the inner wall of the cavity (31).

6. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 5, characterized in that: A through cavity (11) with openings at both ends is fixedly provided inside the piston rod (2).

7. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 6, characterized in that: A V-shaped ring groove (12) adapted to the ring lock groove (5) is fixedly provided on the outer periphery of the piston rod (2), and the V-shaped ring groove (12) is used to define the position of the tightening bolt (6).

8. The connection structure between a hollow piston rod and a piston for a hydraulic cylinder according to claim 7, characterized in that: A connecting portion (13) adapted to the inner diameter of the through cavity (11) is provided on the intermediate body (1) and at a position corresponding to the rear side of the stop ring (7); two threaded connection sections (14) are provided on the outer periphery of the connecting portion (13); two threaded portions (15) are provided on the through cavity (11); the two threaded portions (15) respectively match the two threaded connection sections (14); a ring embedding groove is provided on the connecting portion (13) and at a position corresponding to the position between the two threaded connection sections (14); a sealing ring c (16) for sealing the through cavity (11) is installed on the ring embedding groove.

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