CN210371795U

CN210371795U - Oil buffer

Info

Publication number: CN210371795U
Application number: CN201920561726.0U
Authority: CN
Inventors: 候小康; 喻鹏; 刘培
Original assignee: Zhejiang Xizi Forward Electrical Machinery Co Ltd
Current assignee: Zhejiang Xizi Forward Electrical Machinery Co Ltd
Priority date: 2019-04-23
Filing date: 2019-04-23
Publication date: 2020-04-21
Anticipated expiration: 2029-04-23

Abstract

The application discloses hydraulic buffer includes: the pressure cylinder comprises a base, a first cylinder body and a second cylinder body which are fixed in sequence, and the base, the first cylinder body and the second cylinder body are of split structures; the plunger cylinder comprises a first end cover, a cylinder body and a second end cover which are of split structures and are sequentially fixed, the first end cover, the cylinder body and the second end cover are of split structures, one end, where the second end cover is located, of the plunger cylinder slidably extends into the pressure cylinder, and the second end cover is also provided with an oil passing channel; the return spring is pressed between the pressure cylinder and the plunger cylinder; and the pull rod is positioned in the pressure cylinder, one end of the pull rod is fixed with the base, and the other end of the pull rod penetrates through the second end cover and is provided with a limiting head for limiting the stroke of the plunger cylinder at the penetrating part. The pressure cylinder and the plunger cylinder are designed in a split structure, so that the whole processing and manufacturing difficulty of the hydraulic buffer is reduced, the production cost is reduced, and the hydraulic buffer is assembled to ensure that all accessories are stably connected and is reliable to use.

Description

Oil buffer

Technical Field

The utility model relates to an elevator accessory makes technical field, especially relates to an oil buffer.

Background

The hydraulic buffer in the prior art comprises a plunger cylinder and a pressure cylinder, wherein the plunger cylinder and the pressure cylinder are generally an integrated plunger cylinder and an integrated pressure cylinder, and the plunger cylinder and the pressure cylinder of the integrated structure have the following two processing methods: one is to extrude the tubular blank and then turn it into shape, and the other is to turn it into shape by multiple steps and multiple turns. The former has high requirement on steel due to integral extrusion molding, the ductility of the required steel needs to be good enough, the premise of improving the ductility of the steel is to reduce the strength of the steel, the reduction of the strength can cause the reduction of the safety performance of the buffer, the requirement on the precision of equipment by extrusion molding is high, the reject ratio of finished products is high, and the increase of the processing cost is inevitable. By adopting the latter processing method, the difference between the size of the blank and the size of the finished product is larger due to the over-small wall thickness of the plunger cylinder, the inner diameter and the outer diameter of the upper cylinder body and the lower cylinder body of the pressure cylinder are different, the difference between the inner diameter and the outer diameter of the cylinder body is smaller, the processing allowance is too large, multiple times of processing feeding is needed, the waste of materials is caused, the increase of the processing allowance also causes the increase of the weight of the blank, and the labor intensity and the labor danger of workers are increased. The internal diameter of the plunger body all is less than the internal diameter of fuel sprayer and end cover and can cause the internal diameter of the plunger body to add man-hour, and the process is loaded down with trivial details, takes trouble hard, from blank to finished product, will process many times and feed and just can accomplish processing, so the integral type pressurized cylinder can cause the waste of material and waste time and energy, and production speed is too slow to cause the increase of processing manufacturing cost. In addition, only a single guide sleeve is arranged in the pressure cylinder in the prior art, so that poor guide centering of the plunger cylinder can be caused, and the stability of the buffer is influenced.

SUMMERY OF THE UTILITY MODEL

Therefore, the hydraulic buffer is simple to process and manufacture and convenient to use.

A hydraulic shock absorber, comprising: the pressure cylinder comprises a base, a first cylinder body and a second cylinder body which are fixed in sequence, and the base, the first cylinder body and the second cylinder body are of split structures;

the plunger cylinder comprises a first end cover, a cylinder body and a second end cover which are of split structures and are sequentially fixed, the first end cover, the cylinder body and the second end cover are of the split structures, one end, where the second end cover is located, of the plunger cylinder slidably extends into the pressure cylinder, and an oil passing channel is further formed in the second end cover;

the return spring is pressed between the pressure cylinder and the plunger cylinder;

and the pull rod is positioned in the pressure cylinder, one end of the pull rod is fixed with the base, and the other end of the pull rod penetrates through the second end cover and is provided with a limiting head for limiting the stroke of the plunger cylinder at the penetrating part.

In one embodiment, a gap is reserved at the joint of the pull rod and the second end cover, and the gap forms an oil passing channel.

In one embodiment, the base is provided with a positioning groove, and one end of the first cylinder body is inserted and fixed in the positioning groove; the inner edge of one end, far away from the base, of the first cylinder body is provided with a positioning step, and one end of the second cylinder body is fixedly inserted into the first cylinder body and is abutted against the positioning step along the axial direction of the pressure cylinder.

In one embodiment, the second cylinder body comprises a straight cylinder section and a cylinder wall thickening section which are integrally structured and mutually connected, the cylinder wall thickening section is inserted into the first cylinder body, and the axial end surface of the cylinder wall thickening section is axially abutted against the positioning step along the axial direction of the pressure cylinder; the straight cylinder section is in sliding fit with the extending part of the plunger cylinder.

In one embodiment, a guide sleeve and a seal ring are arranged at the sliding fit position of the plunger cylinder and the straight cylinder section, and a first guide sleeve groove, a first seal groove, a second seal groove and a second guide sleeve groove for mounting the guide sleeve and the seal ring are sequentially and annularly distributed on the inner wall of the straight cylinder section along the direction back to the first cylinder body.

In one embodiment, the first end cap is a ring-shaped structure as a whole; the first end cover sequentially comprises a first annular cover plate and a first positioning ring in the axial direction of the cylinder body, and the first annular cover plate and the first positioning ring are of an integrated structure.

In one embodiment, the second end cap is of generally annular configuration; the second end cover sequentially comprises a second annular cover plate and a second positioning ring in the axial direction of the barrel, the second annular cover plate and the second positioning ring are of an integral structure, and one end, far away from the base, of the pull rod penetrates through the second annular cover plate and is provided with a limiting head for limiting the stroke of the plunger barrel at the penetrating part.

In one embodiment, the first end cap and the second end cap are fixed to the cylinder in the same or different manners, and the fixing manner is at least one of welding, threaded connection and interference fit.

In one embodiment, an annular accommodating groove for accommodating the positioning head is formed in an inner wall of the second positioning ring, and the annular accommodating groove corresponds to the second positioning ring or is located at a junction of the second annular cover plate and the second positioning ring.

In one embodiment, the radial extension part of the end surface of the first cylinder body facing the second cylinder body forms a spring base, the first annular cover plate extends to the periphery of the cylinder body in the radial direction to form a spring top seat, the return spring is sleeved on the periphery of the plunger cylinder, one end of the return spring abuts against the spring top seat, and the other end of the return spring abuts against the spring base.

Other advantages of the present application will be further described in the detailed description.

Drawings

Fig. 1 is a schematic structural diagram of an oil buffer according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of an oil buffer according to an embodiment of the present invention along an axial direction thereof;

FIG. 3 is an enlarged view of a portion of area A of FIG. 2;

FIG. 4 is a cross-sectional view of the pressure cylinder along its own axis according to one embodiment of the present invention;

fig. 5 is a cross-sectional view of the base of one embodiment of the present invention along the axial direction of the pressure cylinder;

fig. 6 is a cross-sectional view of the first cylinder body of one embodiment of the present invention along the axial direction of the pressure cylinder;

fig. 7 is a sectional view of the second cylinder block of one embodiment of the present invention along the axial direction of the pressure cylinder;

fig. 8 is a cross-sectional view of the plunger barrel of one embodiment of the present invention taken along its own axis;

fig. 9 is a cross-sectional view of the first end cap of one embodiment of the present invention taken along the axial direction of the plunger barrel;

fig. 10 is a cross-sectional view of the barrel of one embodiment of the present invention taken along the axial direction of the plunger barrel;

fig. 11 is a cross-sectional view of the second end cap along the axial direction of the plunger barrel according to one embodiment of the present invention.

Description of reference numerals: 1. a pressure cylinder; 11. a first cylinder; 111. positioning a step; 112. a flaring structure; 113. a transition step; 114. a first weld; 12. a second cylinder 121, a straight cylinder section; 122. a cylinder wall thickening section; 123. a first guide sleeve groove; 124. a first seal groove; 125. a second seal groove; 126. a second guide sleeve groove; 1; 13. a base; 131. positioning a groove; 2. a plunger barrel; 21. a first end cap; 211. a first positioning ring; 212. a first annular cover plate; 22. a second end cap; 221. a second positioning ring; 222. a second annular cover plate; 223. an oil passing channel; 23. a barrel; 231. a first annular groove; 232. a second annular groove; 3. a return spring; 31. a spring mount; 32. a spring top seat; 4. a pull rod; 41. a limiting head; 42. an annular receiving groove.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

For a better description and illustration of embodiments of the application, reference may be made to one or more of the drawings, but additional details or examples for describing the drawings should not be construed as limiting the scope of any of the inventive concepts of the present application, the presently described embodiments, or the preferred versions.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "or/and" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1 to 11, a hydraulic shock absorber includes: the pressure cylinder 1 comprises a base 13, a first cylinder body 11 and a second cylinder body 12 which are fixed in sequence, and the base 13, the first cylinder body 11 and the second cylinder body 12 are of split structures; the plunger cylinder 2 comprises a first end cover 21, a cylinder body 23 and a second end cover 22 which are of split structures and are sequentially fixed, the first end cover 21, the cylinder body 23 and the second end cover 22 are of split structures, one end, where the second end cover 22 is located, of the plunger cylinder 2 extends into the pressure cylinder 1 in a sliding mode, and an oil passing channel 223 is further formed in the second end cover 22; the reset spring 3 is pressed between the pressure cylinder 1 and the plunger barrel 2; and the pull rod 4 is positioned in the pressure cylinder 1, one end of the pull rod 4 is fixed with the base 13, and the other end of the pull rod 4 penetrates through the second end cover 22 and is provided with a limiting head 41 for limiting the stroke of the plunger barrel 2 at the penetrating part.

The pressure cylinder 1 comprises a base 13, a first cylinder body 11 and a second cylinder body 12 which are independent and are of a split structure, the base 13, the first cylinder body 11 and the second cylinder body 12 can be respectively processed in the production process, and then the base 13, the first cylinder body 11 and the second cylinder body 12 are assembled into the pressure cylinder 1 for use. Because the base 13, the first cylinder 11 and the second cylinder 12 are small in size relative to the pressure cylinder 1 as a whole, the structure is simple, the manufacturing and processing time can be reduced, and blank materials can be saved.

Similarly, the plunger cylinder 2 comprises a cylinder body 23, a first end cover 21 and a second end cover 22 which are independent and are of split structures, and the cylinder body 23, the first end cover 21 and the second end cover 22 can be processed respectively in the production process, so that the manufacturing time is reduced, and the blank material is saved.

As shown in fig. 2, in the hydraulic shock absorber in a use state, the pressure cylinder 1 is vertically arranged, the base 13 is fixedly provided with a first cylinder 11 (equivalent to a lower cylinder), one end of the first cylinder 11, which is far away from the base 13, is fixedly provided with a second cylinder 12 (equivalent to an upper cylinder), and the inner space of the first cylinder 11 is a first oil storage area; the one end that second end cover 22 located in plunger section of thick bamboo 2 slides and stretches into inside second cylinder 12, and first end cover 21 (being equivalent to the plunger upper cover) is installed at barrel 23 top, and correspondingly, second end cover 22 (being equivalent to the plunger lower cover) is installed to barrel 23 bottom, and the inner space of barrel 23 is the second oil storage area, has still seted up on second end cover 22 and has crossed oil passageway 223, crosses the second oil storage area of oil passageway 223 connection pressure tube 1 in with plunger section of thick bamboo 2. The peripheral cover of plunger section of thick bamboo 2 is equipped with reset spring 3, and reset spring 3 one end is supported and is leaned on first end cover 21, and the other end supports and leans on first cylinder body 11. In the standby state of the hydraulic buffer, corresponding hydraulic oil is stored in the first oil storage area, the second oil storage area is empty, and the return spring 3 is the original length of the return spring; in the working process of the hydraulic buffer, the first end cover 21 of the plunger cylinder 2 bears vertical downward impact and vertically slides downward along the axial direction of the plunger cylinder 2, the second end cover 22 of the plunger cylinder 2 extrudes hydraulic oil in the first oil storage area in the second cylinder 12, the hydraulic oil is subjected to temperature rise and flows to the second oil storage area along the oil passage 223, and the impact on the hydraulic buffer is counteracted through the buffering damping effect of the hydraulic oil; when the impact external force disappears, the hydraulic oil left in the second oil storage area slowly flows back to the first oil storage area under the influence of the self gravity, and meanwhile, the plunger barrel 2 is rebounded to the initial position by the reset spring 3 to wait for the next action.

A pull rod 4 is further arranged inside the pressure cylinder 1 of the hydraulic buffer, one end of the pull rod 4 is fixed with the base 13, and the other end of the pull rod 4 penetrates through a second end cover 22 of the plunger barrel 2 to guide the plunger barrel 2 to slide along the axial direction of the plunger barrel 2, wherein in one embodiment, as shown in the figure, the ratio of the diameter of the pull rod 4 to the outer diameter of a barrel 23 of the plunger barrel 2 is 0.3-0.35: 1. In order to prevent the plunger barrel 2 from being released from the pressure cylinder 1 under the rebounding action of the return spring 3, a limiting head 41 for limiting the stroke of the plunger barrel 2 is arranged at the position where the pull rod 4 penetrates out of the second end cover 22, and the limiting head 41 abuts against the second end cover 22 to limit the highest rebounding position of the plunger barrel 2 so as to avoid being released from the pressure cylinder 1.

The hydraulic shock absorber resists shock by the damping effect of the hydraulic oil, the magnitude of the damping effect of the hydraulic oil is related to the size of the oil passing passage 223, and generally, the damping effect of the hydraulic oil is smaller when the oil passing passage 223 is larger, and the damping effect of the hydraulic oil is larger when the oil passing passage 223 is smaller. In order to prevent the plunger cylinder 2 of the hydraulic shock absorber from rigidly impacting the bottom of the pressure cylinder 1 when the plunger cylinder is operated to the end, the specification of the oil passage 223 is critical when designing the hydraulic shock absorber. In one embodiment, as shown in fig. 3, a gap is left at the matching position of the pull rod 4 and the second end cover 22, the gap forms an oil passing channel 223, the radial height of the oil passing channel 223 is firstly reduced and then increased along the axial direction of the plunger barrel 2, and the ratio of the radial height of the narrowest position of the oil passing channel 223 (namely, the radial height of the gap h between the pull rod 4 and the narrowest position of the inner hole of the second end cover 22 in the radial direction of the oil passing channel 223) to the diameter of the pull rod 4 is 1-5: 100.

The whole pressure cylinder 1 of the hydraulic buffer is assembled by a base 13, a first cylinder 11 and a second cylinder 12, in one embodiment, as shown in fig. 4, a positioning groove 131 is formed on the base 13, and one end of the first cylinder 11 can be inserted into the positioning groove 131 and fixedly connected with the base 13, or fixedly connected with the base 13 by welding; the inner edge of the first cylinder body 11 far away from one end of the base 13 is provided with a positioning step 111, one end of the second cylinder body 12 can be inserted into the first cylinder body 11 and is abutted against the positioning step 111 along the axial direction of the pressure cylinder 1, so as to be fixedly connected with the first cylinder body 11, and for ensuring the stable connection between the first cylinder body and the second cylinder body, the first cylinder body 11 and the second cylinder body 12 can also adopt welding, threaded connection, riveting and interference fit mode fixed connection, and can also adopt combination of various connection modes, for example, adopt the interference fit mode to install and then weld after being in place, further ensure the installation precision and the overall strength, and the various fixed connection modes can be flexibly matched and used according to the size, the material and other factors of the first cylinder body 11 and the second cylinder body 12.

In one embodiment, as shown in fig. 7, the second cylinder 12 includes a cylindrical section 121 and a wall-thickened section 122 that are integrally formed and connected to each other, the inner diameter of the wall-thickened section 122 is the same as that of the cylindrical section 121, the outer diameter of the wall-thickened section 122 is greater than that of the cylindrical section 121, and specifically, the ratio of the outer diameters of the wall-thickened section 122 and the cylindrical section 121 is 1.05-1.1: 1. When the second cylinder body 12 needs to be inserted into the first cylinder body 11 for fitting, the cylinder wall thickening section 122 may be inserted into the first cylinder body 11, and an axial end surface of the cylinder wall thickening section 122 is axially abutted against the positioning step 111 along the pressure cylinder 1, and an outer diameter of the cylinder wall thickening section 122 may be equal to an inner diameter of the positioning step 111, or an outer diameter of the cylinder wall thickening section 122 is slightly larger than the inner diameter of the positioning step 111, so that the two are fixedly connected through interference fit.

In order to ensure the first cylinder 11 and the second cylinder 12 are connected firmly, in one embodiment, the outer circumference of the cylinder wall thickening section 122 is provided with an external thread, correspondingly, the inner wall of the positioning step 111 is provided with an internal thread, and when the cylinder wall thickening section 122 is inserted into the first cylinder 11, the cylinder wall thickening section is fastened and connected through the matching of the internal thread and the external thread.

The straight section of thick bamboo 121 of second cylinder 12 stretches into partial sliding fit with plunger section of thick bamboo 2, and for better direction centering plunger section of thick bamboo 2 slides from top to bottom along self axial direction, plunger section of thick bamboo 2 sets up one or more uide bushing with straight section of thick bamboo 121 sliding fit department, and for satisfying the sealed requirement of hydraulic buffer, plunger section of thick bamboo 2 still is provided with one or more sealing washer with straight section of thick bamboo 121 sliding fit department simultaneously. In one embodiment, as shown in the figure, the inner wall of the straight cylinder section 121 is sequentially and annularly provided with a first guide sleeve groove 123, a first seal groove 124, a second seal groove 125 and a second guide sleeve groove 126 for installing a guide sleeve and a seal ring in a direction away from the first cylinder 11. Because the height of the guide sleeve is greater than that of the seal ring, the size of the guide sleeve groove is greater than that of the seal groove in the axial direction of the second cylinder body 2, specifically, the size ratio of the first guide sleeve groove 211, the first seal groove 221, the second seal groove 222 and the second guide sleeve groove 212 in the axial direction of the second cylinder body 2 is 2:1:1:2, wherein the inner diameters of the first guide sleeve groove 211 and the second guide sleeve groove 212 are the same, the inner diameters of the first seal groove 221 and the second seal groove 222 are the same, and the inner diameter ratio of the guide sleeve groove to the seal groove is 1-1.05: 1. Through the cooperation that sets up two uide bushings and plunger section of thick bamboo 2, reduce plunger section of thick bamboo 2 as far as and receive the external force influence skew to predetermine the orbit's the condition, improve the overall stability of hydraulic buffer.

To facilitate the insertion of the first cylinder 11 and the second cylinder 12, in one embodiment, as shown in fig. 6, the inner wall of the first cylinder 11 is provided with a flaring structure 112 on the side facing the second cylinder 12. The flaring structure 112 starts from the end face of the positioning step 111 facing the second cylinder 12 and opens at the end face of the first cylinder 11 facing the second cylinder 12, and the size ratio of the flaring structure 112 to the first cylinder 11 in the axial direction of the first cylinder 11 is 0.03-0.1: 1. The inner diameters of the rest parts of the first cylinder body 11 except the flaring structure 112 and the positioning step 111 are the same, and the ratio of the inner diameter of the first cylinder body to the inner diameter of the second cylinder body 12 is 1.2-1.25: 1.

Since the outer diameter of the cylinder wall thickened section 122 of the second cylinder body 12 is larger than that of the straight cylindrical section 121, in one embodiment, as shown in fig. 7, a transition step 113 is formed at the joint of the cylinder wall thickened section 122 and the straight cylindrical section 121 on the outer wall of the second cylinder body 12, and when the second cylinder body 12 is inserted and fixed in the first cylinder body 11, the end surface of the first cylinder body 11, which is opposite to one end of the base 13, is aligned with the transition step. In order to ensure that the first cylinder 11 and the second cylinder 12 are connected stably, a welding connection mode may be further adopted at the mating end of the first cylinder 11 and the second cylinder 12, in one embodiment, as shown in fig. 4, a welding groove is respectively provided on an end surface of the first cylinder 11 facing away from the base 13 and the transition step, and the welding connection of the first cylinder 11 and the second cylinder 12 is completed at the welding groove and a first welding seam 114 is formed. The welding groove is preset at the end face and the transition step of the first cylinder body 11, so that the preparation work before welding in the installation process can be simplified, and the welding and fixing quality is ensured.

In order to cooperate with the pull rod 4 of the hydraulic buffer, the entire plunger cylinder 2 needs to be ensured to be vertically through, so in one embodiment, as shown in fig. 9 to 11, the first end cover 21 and the second end cover 22 in the plunger cylinder 2 are both annular structures as a whole, specifically, the first end cover 21 sequentially includes a first positioning ring 211 and a first annular cover plate 212 in the axial direction of the cylinder 23, and the size ratio of the first positioning ring 211 to the first annular cover plate 212 in the axial direction of the cylinder 23 is 1.1 to 1.2: 1. To reduce the manufacturing and subsequent assembly steps, the first retainer ring 211 and the first annular cover plate 212 may be integrally formed from the same blank. In the process of assembling the first end cap 21 to the first end of the cylinder 23, the first positioning ring 211 is inserted into the first annular groove 231 on the inner wall of the first end of the cylinder 23, and the first annular cover plate 212 is attached to the end surface of the first end of the cylinder 23, so as to complete the sealing assembly of the first end of the cylinder 23. The first annular groove 231 is sized to mate with the first retaining ring 211 to receive the first retaining ring 211 inserted into the barrel 23; or the inner diameter of the first annular groove 231 is slightly smaller than the outer diameter of the first positioning ring 211, so that the two are fixedly connected through interference fit.

Similarly, the second end cap 22 is generally annular in configuration; the second end cover 22 sequentially comprises a second positioning ring 221 and a second annular cover plate 222 in the axial direction of the cylinder 23, the outer diameter of the second annular cover plate 222 is the same as that of the cylinder 23, and the size ratio of the second positioning ring 221 to the second annular cover plate 222 in the axial direction of the cylinder 23 is 1.1-1.2: 1. To reduce the manufacturing and subsequent assembly steps, the second retaining ring 221 and the second annular cover plate 222 may be formed as a unitary structure from the same blank. During the process of assembling the second end cap 22 to the second end of the cylinder 23, the second positioning ring 221 is inserted into the second annular groove 232 on the inner wall of the second end of the cylinder 23, and the second annular cover plate 222 is attached to the end surface of the second end of the cylinder 23, so as to complete the sealing assembly of the second end of the cylinder 23. The second annular groove 232 is sized to match the second retaining ring 221, or the inner diameter of the second annular groove 232 is slightly smaller than the outer diameter of the second retaining ring 221, so that the two are fixedly connected by interference fit.

In order to ensure the connection stability of the first end cover 21, the second end cover 22 and the cylinder 23, the first end cover 21 and the second end cover 22 may be fixedly connected to the cylinder 23 by welding, screwing, riveting or interference fit, or may be combined by multiple connection methods, for example, welding after being mounted in place by interference fit, so as to further ensure the mounting accuracy and the overall strength.

In one embodiment, the first positioning ring 211 has an external thread formed on the outer circumference thereof, and correspondingly, an internal thread formed on the inner wall of the first annular groove 231, so that when the first positioning ring 211 is inserted into the first annular groove 231, the first positioning ring is fastened by the engagement of the internal and external threads.

The middle of the second end cover 22 of the annular structure is provided with a pull rod 4, the part of the pull rod 4 penetrating out of the second end cover 22 is provided with a limiting head 41, in one embodiment, as shown in fig. 2, one end of the pull rod 4 far away from the base 13 penetrates through the second annular cover plate 222, the part penetrating out of the second annular cover plate 222 is provided with the limiting head 41 for limiting the stroke of the plunger cylinder 2, the radial dimension of the limiting head 41 is larger than that of the pull rod 4, and the stroke of the plunger cylinder 2 under the action of a spring is limited by the abutting of the contact surface of the limiting head 41 and the second annular cover plate 222, so that the plunger cylinder 2 is prevented from being ejected upwards and out of.

Due to the arrangement of the positioning head 41, in one embodiment, as shown in fig. 11, an annular receiving groove 42 for receiving the positioning head 41 may be formed on an inner wall of the second positioning ring 221, and the position of the annular receiving groove 42 corresponds to the second positioning ring 221, or is located at a boundary portion between the second annular cover plate 222 and the second positioning ring 221.

The return spring 3 acts on the plunger barrel 2, and rebounds the plunger barrel 2 to the initial position to wait for the next action after the external force disappears, in one embodiment, as shown in fig. 2, the radially extending portion of the end surface of the first cylinder 11 facing the second cylinder 12 forms a spring base 31, the radially extending portion of the first annular cover plate 212 extends to the periphery of the barrel 23 to form a spring top seat 32, the return spring 3 is sleeved on the periphery of the plunger barrel 2, and one end of the spring abuts against the spring top seat 32, and the other end abuts against the spring base 31. When the plunger barrel 2 is at the initial position, the reset spring 3 is the original length, when the plunger barrel 2 slides downwards under the pressure, the reset spring 3 is compressed under the pressure of the spring top seat 32, and after the external force disappears, the reset spring 3 recovers to the original length and rebounds the plunger barrel 2 to the initial position.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above examples only represent some embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A hydraulic shock absorber, comprising:

the pressure cylinder comprises a base, a first cylinder body and a second cylinder body which are fixed in sequence, and the base, the first cylinder body and the second cylinder body are of split structures;

the plunger cylinder comprises a first end cover, a cylinder body and a second end cover which are fixed in sequence, the first end cover, the cylinder body and the second end cover are of a split structure, one end, where the second end cover is located, of the plunger cylinder extends into the pressure cylinder in a sliding mode, and an oil passing channel is further formed in the second end cover;

2. A hydraulic damper according to claim 1 wherein a gap is provided between the engagement of said rod and said second end cap, said gap defining an oil passage.

3. A hydraulic shock absorber according to claim 1, wherein the base is provided with a positioning groove, and one end of the first cylinder is inserted and fixed in the positioning groove; the inner edge of one end, far away from the base, of the first cylinder body is provided with a positioning step, and one end of the second cylinder body is fixedly inserted into the first cylinder body and is abutted against the positioning step along the axial direction of the pressure cylinder.

4. A hydraulic shock absorber according to claim 3, wherein the second cylinder block includes a straight cylinder section and a cylinder wall thickening section which are integrally formed and joined to each other, the cylinder wall thickening section is inserted into the first cylinder block, and an axial end face of the cylinder wall thickening section is axially abutted against the positioning step along the pressure cylinder; the straight cylinder section is in sliding fit with the extending part of the plunger cylinder.

5. An oil damper according to claim 4, wherein a guide sleeve and a seal ring are provided at a sliding fit portion of the plunger cylinder and the straight cylinder section, and a first guide sleeve groove, a first seal groove, a second seal groove, and a second guide sleeve groove for mounting the guide sleeve and the seal ring are annularly arranged in this order along a direction away from the first cylinder body on an inner wall of the straight cylinder section.

6. A hydraulic shock absorber according to claim 1, wherein the first end cap is of generally annular configuration; the first end cover sequentially comprises a first annular cover plate and a first positioning ring in the axial direction of the cylinder body, and the first annular cover plate and the first positioning ring are of an integrated structure.

7. A hydraulic damper according to claim 6, wherein said second end cap is of generally annular configuration; the second end cover sequentially comprises a second annular cover plate and a second positioning ring in the axial direction of the barrel, the second annular cover plate and the second positioning ring are of an integral structure, and one end, far away from the base, of the pull rod penetrates through the second annular cover plate and is provided with a limiting head for limiting the stroke of the plunger barrel at the penetrating part.

8. An oil damper as claimed in claim 7, wherein the first and second end caps are fixed to the cylinder in the same or different manner, and the fixing manner is at least one of welding, screwing, and interference fitting.

9. An oil buffer as claimed in claim 7, wherein the inner wall of the second positioning ring is formed with an annular receiving groove for receiving the positioning head, and the annular receiving groove is located at a position corresponding to the second positioning ring or at a junction of the second annular cover plate and the second positioning ring.

10. An oil damper as claimed in claim 9, wherein the radially extending portion of the end surface of said first cylinder facing said second cylinder forms a spring seat, said first annular cover plate extends radially to the outer periphery of said cylinder to form a spring top seat, said return spring is fitted around the outer periphery of said plunger cylinder, and said return spring has one end abutting against said spring top seat and the other end abutting against said spring seat.