CN111255765B

CN111255765B - Oil hydraulic cylinder capable of exhausting and series-connection type synchronous oil hydraulic cylinder system

Info

Publication number: CN111255765B
Application number: CN201910068933.7A
Authority: CN
Inventors: 郭本源; 朱冏昇
Original assignee: Ashun Fluid Power Co ltd
Current assignee: Ashun Fluid Power Co ltd
Priority date: 2018-11-30
Filing date: 2019-01-24
Publication date: 2022-03-18
Anticipated expiration: 2039-01-24
Also published as: CN111255765A; TW202022240A; TWI686546B

Abstract

The invention discloses an oil hydraulic cylinder capable of exhausting and a series synchronous oil hydraulic cylinder system, wherein the oil hydraulic cylinder comprises a cylinder body, a piston, a sealing ring arranged on the piston and an exhaust hole arranged on the cylinder body; the cylinder body is provided with an upper chamber, an upper pore channel, an upper joint communicated with the upper chamber through the upper pore channel, a lower chamber, a lower pore channel and a lower joint communicated with the lower chamber through the lower pore channel; the discharge hole is communicated with the lower joint and is positioned above the lower pore channel; when the piston is located at a starting point and the sealing ring is located below the discharge hole, the discharge hole is communicated with the upper cavity, and when the piston moves to an end point and the sealing ring is located above the discharge hole, the discharge hole is communicated with the lower cavity. The tandem type synchronous hydraulic cylinder system formed by the hydraulic cylinders capable of exhausting air can exhaust the air in the system.

Description

Oil hydraulic cylinder capable of exhausting and series-connection type synchronous oil hydraulic cylinder system

Technical Field

The invention relates to an oil hydraulic cylinder, in particular to a synchronous oil hydraulic cylinder.

Background

In many cases where two or more cylinders are required to operate synchronously, a tandem synchronous cylinder system is often adopted, which can be seen in patents CN 104806589B, CN 205423367U and CN 207131652U, and taiwan patent No. M562347.

However, after the two synchronous cylinders are assembled to form the tandem type synchronous cylinder system, air is inevitably left in the system. Taking the patent with chinese grant publication No. CN 104806589B as an example, after the two synchronous hydraulic cylinders are connected by the pipeline, the space between the first cavity, the third cavity and the pipeline is inevitably filled with residual air, which can run away from the space along with the movement of the first piston and the second piston, and cannot be exhausted, thereby affecting the synchronous operation and the service life of the two synchronous hydraulic cylinders.

Disclosure of Invention

In order to solve the above problems, the present invention provides a hydraulic cylinder capable of exhausting air, and a tandem type synchronous hydraulic cylinder system formed by using the hydraulic cylinder, which can exhaust air in the system.

In order to achieve the above object, the present invention provides an oil hydraulic cylinder capable of exhausting air, which includes a cylinder body, a piston rod, a sealing ring and an exhaust hole; the cylinder body is provided with an upper cavity, an upper pore channel, an upper joint communicated with the upper cavity through the upper pore channel, a lower cavity, a lower pore channel and a lower joint communicated with the lower cavity through the lower pore channel; the piston is movably arranged in the cylinder body and can move back and forth between a starting point and a finishing point in the cylinder body; the piston rod is connected with the piston; the sealing ring is sleeved on the piston and is provided with an outer peripheral wall, and the outer peripheral wall is tightly attached to an inner wall surface of the cylinder body to form sealing so as to isolate the upper chamber from the lower chamber; the discharge hole is arranged on the cylinder body and communicated with the lower joint, and the discharge hole is positioned above the lower pore channel; wherein the discharge hole communicates with the upper chamber when the piston is positioned at the start point and the seal ring is positioned below the discharge hole, and the discharge hole communicates with the lower chamber when the piston moves to the end point to position the seal ring above the discharge hole.

In one embodiment, the drain hole has a small diameter section leading to the lower chamber and a large diameter section leading to the lower joint.

In one embodiment, the inner diameter of the lower duct is larger than the hole diameter of the discharge hole, and the inner diameter of the lower duct is equal to the inner diameter of the upper duct.

In one embodiment, the oil pressure cylinder capable of exhausting air further includes an O-ring, the O-ring is sleeved on the piston, and the O-ring is clamped between the piston and the sealing ring.

In an embodiment of the present invention, the oil hydraulic cylinder capable of exhausting air further includes a wear ring sleeved on the piston and located above the sealing ring, and an outer peripheral wall of the wear ring abuts against an inner wall surface of the cylinder body.

The invention also provides a tandem type synchronous oil pressure cylinder system which comprises a connecting pipe and two oil pressure cylinders capable of exhausting, wherein the two oil pressure cylinders capable of exhausting are respectively a first oil pressure cylinder capable of exhausting and a second oil pressure cylinder capable of exhausting, two ends of the connecting pipe are respectively connected with an upper connector of the first oil pressure cylinder capable of exhausting and a lower connector of the second oil pressure cylinder capable of exhausting, and the volume of an upper chamber of the first oil pressure cylinder capable of exhausting, which is used for containing hydraulic oil, is equal to the volume of a lower chamber of the second oil pressure cylinder capable of exhausting, which is used for containing the hydraulic oil.

In one embodiment, in the above system of the present invention, an inner diameter of the cylinder of the first evacuable hydraulic cylinder is larger than an inner diameter of the cylinder of the second evacuable hydraulic cylinder.

Through the arrangement of the discharge hole, air in the tandem type synchronous oil hydraulic cylinder system can be discharged, the synchronism of the tandem type synchronous oil hydraulic cylinder system in operation is ensured, and the service life is prolonged.

Drawings

The drawings are only for purposes of illustrating and explaining the present invention and are not to be construed as limiting the scope of the present invention. Wherein:

fig. 1 shows a cross-sectional view of a preferred embodiment of the invention (piston at start).

Figure 2 shows a cross-sectional view of a preferred embodiment of the invention (piston at terminus).

FIG. 3 shows an enlarged partial cross-sectional view of a preferred embodiment of the present invention.

The reference numbers illustrate:

1. 1a dischargeable

hydraulic cylinders

11, 11a

110 inner wall surface 110a and outer wall surface

111. 111a

upper chambers

112, 112a lower chambers

113. 113a

upper joint

114, 114a upper hole

115. 115a

lower joints

116, 116a lower duct

12. 12a

piston

13, 13a piston rod

14.

14a sealing ring

15, 15a outlet

16. 16a wear

ring

131, 131a O type ring

2 inlet and outlet of connecting pipe A

Detailed Description

In order to clearly understand the technical solution, the purpose and the effect of the present invention, a detailed description of the present invention will be described with reference to the accompanying drawings.

Fig. 1 and 2 show a preferred embodiment of the ventable hydraulic cylinder of the present invention, in which a ventable hydraulic cylinder 1 (a first ventable hydraulic cylinder) and a ventable hydraulic cylinder 1a (a second ventable hydraulic cylinder) are connected by a connecting pipe 2 to form a tandem synchronous hydraulic cylinder system. One of the oil hydraulic cylinders 1 capable of exhausting air comprises a cylinder body 11, a piston 12, a piston rod 13, a sealing ring 14 and an exhaust hole 15; the cylinder 11 has an inner wall surface 110, an outer wall surface 110a, an upper chamber 111 and a lower chamber 112 both defined by the inner wall surface 110; the piston 12 is movably disposed in the cylinder 11 and can move back and forth between a starting point (shown in fig. 1) and an ending point (shown in fig. 2) in the cylinder 11; the piston rod 13 is connected with the piston 12, the piston rod 13 is positioned in the upper chamber 111 and extends forwards out of the cylinder 11, and can extend and retract along with the movement of the piston 12; the cylinder 11 further has an upper joint 113 and an upper duct 114 penetrating from the inner wall surface 110 to the outer wall surface 110a, the upper joint 113 is disposed on the outer wall surface 110a of the cylinder 11, and directly communicates with the upper duct 114, and communicates with the upper chamber 111 via the upper duct 114; the cylinder block 11 further has a lower joint 115 and a lower port 116 penetrating from the inner wall surface 110 to the outer wall surface 110a, and the lower joint 115 is provided on the outer wall surface 110a of the cylinder block 11, directly communicates with the lower port 116, and communicates with the lower chamber 112 via the lower port 116. The lower joint 116 also has an inlet opening a facing the outer wall surface 110a of the cylinder 11.

As shown in fig. 1 and 3, the sealing ring 14 is sleeved on the piston 12, and the outer peripheral wall of the sealing ring 14 is tightly attached to the inner wall surface 110 of the cylinder 11 to form a seal, thereby isolating the upper chamber 111 and the lower chamber 112, so that the hydraulic oil or other media in the two chambers do not leak from one to the other. In this embodiment, an O-ring 131 is also interposed between the sealing ring 14 and the piston 12. In addition, the piston 12 is sleeved with a wear-resistant ring 16, and the wear-resistant ring 16 is positioned above the sealing ring 14 to ensure that the piston 12 moves vertically without deviation; the outer peripheral wall of the wear ring 16 abuts against the inner peripheral wall of the cylinder block 11, but does not form a seal as does the seal ring 14.

The discharge port 15 penetrates from the inner wall surface 110 to the outer wall surface 110a of the cylinder block 11, directly communicates with the lower joint 115, and is located above the lower port 116. When the piston 12 is positioned at the starting point as shown in fig. 1 such that the sealing ring 14 is positioned below the discharge hole 15, the discharge hole 15 communicates with the upper chamber 111, and the lower port 116 is positioned below the sealing ring 14 to communicate with the lower chamber 112. When piston 12 is moved to the end such that sealing ring 14 is positioned over discharge hole 15, discharge hole 15 and lower port 116 are both in communication with lower chamber 112. Wherein the inner diameter of discharge hole 15 is preferably smaller than lower orifice 116.

The other ventable hydraulic cylinder 1a is similar in structure to the ventable hydraulic cylinder 1, and therefore includes a cylinder 11a, a piston 12a, a piston rod 13a, a sealing ring 14a and a discharge hole 15a, where the cylinder 11a also has an upper chamber 111a, a lower chamber 112a, an upper joint 113a, an upper port 114a, a lower joint 115a and a lower port 116 a. Piston 12a also has a sealing ring 14a, O-ring 131a and a wear ring 16 a. The structures and functions of these components are the same as those of the corresponding components of the above-mentioned exhaust oil hydraulic cylinder 1, and are not described in detail.

In this embodiment, the inner diameter of the cylinder 11 of one of the hydraulic cylinders 1 is larger than the inner diameter of the cylinder 11a of the other hydraulic cylinder 1a, but the volume of the former upper chamber 111 is equal to the volume of the latter lower chamber 112a, and the volume referred to herein is the volume for containing the hydraulic oil. Therefore, the upper joint 113 of one of the dischargeable cylinders 1 and the lower joint 115a of the other dischargeable cylinder 1a are connected by the connecting pipe 2, thereby forming a tandem type hydraulic synchronous system (hereinafter referred to as a system) in which both

piston rods

13, 13a can be synchronously extended and retracted.

In this system, as shown in fig. 1, when an oil pressure circuit (including a tank, not shown) feeds oil into the lower joint 115 of the one of the ventable oil cylinders 1, hydraulic oil from the oil pressure circuit enters the lower chamber 112 through the lower port 116 and pushes the piston 12 to move upward from the starting point to the ending point. Since the upper chamber 111 is communicated with the lower chamber 112a through the upper port 114, the connecting tube 2 and the lower port 116a of the other deflatable hydraulic cylinder 1a, the upward movement of the piston 12 pushes the hydraulic oil in the upper chamber 111, the connecting tube 2 and the lower chamber 112a, so that the piston 12a also moves upward from the starting point to the end point, and pushes the hydraulic oil (or other medium) in the upper chamber 111a to flow out from the upper joint 113a through the upper port 114a, thereby achieving the synchronous upward movement of the piston rod 13 and the piston rod 13 a. On the contrary, when the oil pressure circuit takes oil into the upper joint 113a of the other oil pressure cylinder 1a capable of exhausting, as shown in fig. 2, the hydraulic oil from the oil pressure circuit enters the upper chamber 111a through the upper duct 114a and pushes the piston 12a to move downward from the end point to the start point, and the downward movement of the piston 12a pushes the hydraulic oil in the lower chamber 112a, the connecting pipe 2 and the upper chamber 111, so that the piston 12 also moves downward from the end point to the start point, thereby achieving the synchronous downward movement of the piston rod 13 and the piston rod 13 a.

In the previous description, the

cylinders

11 and 11a and the connecting pipe 2 are filled with hydraulic oil, and how the hydraulic oil is filled into the

empty cylinder

11 and 11a will be described. As shown in fig. 1, the connecting pipe 2 connects the empty cylinder 11 and the cylinder 11a, and the upper joint 113a and the lower joint 115 are connected to the hydraulic circuit, respectively, and air is present in the

cylinders

11 and 11a and the connecting pipe 2. First, the hydraulic circuit feeds hydraulic oil into the upper chamber 111a of the cylinder 11a through the upper joint 113a to fill the upper chamber 111a with the hydraulic oil, flows into the discharge hole 15a through a gap (located above the seal ring 14 a) between the piston 12a and the inner wall surface of the cylinder 11a, and then flows into the upper chamber 111 of the cylinder 11 through the discharge hole 15a and the connection pipe 2. In this process, a part of the hydraulic oil also flows into the lower chamber 112a of the cylinder 11a through the lower port 116 a.

As the hydraulic oil continues to be supplied, the hydraulic oil fills the upper chamber 111, flows through the gap between the piston 12 and the inner wall surface of the cylinder 11 (above the seal ring 14), flows to the discharge hole 15, flows into the hydraulic circuit through the discharge hole 15 and the lower joint 115, and then returns to the tank. In the process, a part of the hydraulic oil flows into the lower chamber 112 of the cylinder 11 through the lower port 116. After the hydraulic oil is supplied for a certain period of time, the upper and

lower chambers

111a and 112a of the cylinder 11a, and the upper and

lower chambers

111 and 112 of the cylinder 11 are filled with the hydraulic oil, so that the piston rod 13 and the piston rod 13a can be lifted.

In the process of supplying the hydraulic oil, the air originally present in the upper chamber 111a is pushed down by the hydraulic oil supplied from the upper joint 113a, flows to the discharge hole 15a through the gap between the piston 12a and the inner wall surface of the cylinder 11a, and flows into the upper chamber 111 of the cylinder 11 through the discharge hole 15a and the connection pipe 2. The air in the upper chamber 111 flows through a gap between the piston 12 and the inner wall surface 110 of the cylinder 11 to the discharge hole 15, flows into the hydraulic circuit through the discharge hole 15 and the lower joint 115, flows into the oil tank, and is discharged to the outside by an exhaust mechanism of the oil tank. Among them, the venting mechanism of the oil tank is known in the art, for example: taiwan patent No. 200609176 discloses that an oil tank has a vent valve for exhausting air in the oil tank out of the oil tank; taiwan publication No. M431812 discloses an oil tank in an oil pressure power system having an air vent hole; the invention patent application with the Chinese application publication number of CN107934784A discloses that an oil tank can be exhausted and decompressed through a manual exhaust rod; the invention patent with Chinese grant publication No. CN105805060B discloses a hydraulic oil tank having an exhaust port; the invention patent application with the Chinese application publication number of CN107781235A discloses that an oil tank is provided with an automatic exhaust valve; the invention application with the Chinese application publication number of CN106640785A discloses a hydraulic safety oil tank, which is provided with an exhaust device exhaust box, an exhaust column and an exhaust port, so that the oil tank can exhaust air quickly.

It should be noted that although the piston 12 and the piston 12a are respectively sleeved with the wear-resistant ring 16 and the wear-resistant ring 16a in this embodiment, as described above, the wear-resistant ring 16 and the wear-resistant ring 16a do not form a seal as the seal ring 14 and the seal ring 14a do, so that the hydraulic oil and air pushed by the hydraulic oil and the air can still flow through the gap between the wear-resistant ring 16 and the cylinder 11 and also flow through the gap between the wear-resistant ring 16a and the cylinder 11 a.

As is apparent from the above description, the air originally present in the

cylinders

11 and 11a and the connecting pipe 2 is discharged out of the

cylinders

11 and 11a in the process of filling the

cylinders

11 and 11a with the hydraulic oil by the provision of the discharge holes 15 and 15 a. Therefore, no air exists in the system, the synchronism of the system in operation can be ensured, and the service life can be prolonged.

In the above-mentioned hydraulic oil filling process, or in the case where a small amount of air is leaked into the lower chamber 112a of the cylinder 11a and/or the lower chamber 112 of the cylinder 11, even if the lifting operation of the piston rod 13 and the piston rod 13a is further performed one or more times, the air is completely driven into the oil tank and discharged to the outside by the oil tank exhaust mechanism. For example, the piston rod 13 and the piston rod 13a may be moved up together by the oil fed from the joint 115 and then moved down together by the oil fed from the joint 113 a. During the downward movement, air in the lower chamber 112 is pushed into the hydraulic circuit by the downward movement of the piston 12, then enters the tank and is exhausted to the outside by the tank's exhaust mechanism. The air in the lower chamber 112a enters the upper chamber 111 through the connecting pipe 2 due to the downward movement of the piston 12a, and when the

pistons

12 and 12a move downward to the positions shown in fig. 1, as long as the hydraulic oil is continuously supplied from the joint 113a, the air in the upper chamber 111 flows to the discharge hole 15 through the gap between the piston 12 and the inner wall surface 110 of the cylinder 11, flows into the hydraulic circuit through the discharge hole 15 and the lower joint 115, flows into the oil tank, and is discharged to the outside by the exhaust mechanism of the oil tank.

In this embodiment, as shown in fig. 3, the discharge port 15a of the other ventable hydraulic cylinder 1a has a small diameter section 151a having a smaller inner diameter and leading to the inside of the cylinder block 11a, and a large diameter section 152a having a larger inner diameter and leading to the lower joint 115a, but the inner diameter of the entire discharge port 15a may be the same. The oil pressure cylinder 1 capable of exhausting air is also omitted. One end of the large-diameter section 152a is located on the outer wall surface of the cylinder 11a, the other end of the large-diameter section 152a is communicated with one end of the small-diameter section 151a, and the other end of the small-diameter section 151a is located on the inner wall surface of the cylinder 11 a. The large diameter section 152a of the discharge hole 15a and the lower port 116a directly communicate with the inlet/outlet a of the lower joint 115 a.

Preferably, the inner diameter of the lower port 116a of the other ventable hydraulic cylinder 1a is larger than the discharge hole 15a and equal to the inner diameter of the upper port 114a, but the inner diameter of the lower port 116a may be equal to or smaller than the discharge hole 15 a. The oil pressure cylinder 1 capable of exhausting is not described in detail.

As described above, the ventable hydraulic cylinder of the present invention can solve the problem of residual air in the conventional tandem synchronous hydraulic cylinder system by providing the discharge hole, thereby ensuring the synchronization of the operation and increasing the service life of the tandem synchronous hydraulic cylinder system constituted by the ventable hydraulic cylinder of the present invention.

The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. Any equivalent changes and modifications that can be made by one skilled in the art without departing from the spirit and principles of the invention should fall within the protection scope of the invention. It should be noted that the components of the present invention are not limited to the above-mentioned whole application, and various technical features described in the present specification can be selected to be used alone or in combination according to actual needs, so that the present invention naturally covers other combinations and specific applications related to the invention.

Claims

1. A ventable oil hydraulic cylinder, comprising:

the cylinder body is provided with an inner wall surface, an outer wall surface, an upper cavity and a lower cavity which are defined by the inner wall surface, and an upper pore passage and a lower pore passage which penetrate through the outer wall surface from the inner wall surface, wherein the upper pore passage is communicated with the upper cavity, the lower pore passage is communicated with the lower cavity, and the inner diameter of the lower pore passage is equal to the inner diameter of the upper pore passage;

the piston can be movably arranged in the cylinder body and can move back and forth between a starting point and an ending point in the cylinder body;

a piston rod connected to the piston;

the sealing ring is sleeved on the piston and provided with an outer peripheral wall, and the outer peripheral wall is tightly attached to the inner wall surface of the cylinder body to form sealing so as to isolate the upper chamber from the lower chamber;

the upper joint is arranged on the outer wall surface of the cylinder body and is directly communicated with the upper pore channel of the cylinder body;

a lower joint arranged on the outer wall surface of the cylinder body and directly communicated with the lower pore channel of the cylinder body, wherein the lower joint is provided with an inlet and an outlet facing to the outer wall surface of the cylinder body;

a discharge hole penetrating from the inner wall surface of the cylinder to the outer wall surface of the cylinder and directly communicating with the lower joint, the discharge hole being located above the lower duct, wherein, when the piston is positioned at the starting point and the sealing ring is positioned below the discharge hole, the discharge hole is communicated with the upper chamber, when the piston moves to the end point to make the sealing ring above the discharge hole, the discharge hole is communicated with the lower chamber, wherein the inner diameter of the discharge hole is smaller than that of the lower pore canal, the discharge hole is provided with a large-diameter section and a small-diameter section with the inner diameter smaller than that of the large-diameter section, one end of the large diameter section is positioned on the outer wall surface of the cylinder body, the other end of the large diameter section is communicated with one end of the small diameter section, the other end of the small diameter section is positioned on the inner wall surface of the cylinder body, wherein the large diameter section of the discharge hole and the lower duct are respectively and directly communicated with the inlet and the outlet of the lower joint.

2. The de-airing hydraulic cylinder according to claim 1, further comprising an O-ring, wherein the O-ring is fitted over the piston and sandwiched between the piston and the sealing ring.

3. The de-ventable oil hydraulic cylinder as claimed in claim 1, further comprising a wear ring fitted over the piston and above the sealing ring, wherein an outer peripheral wall of the wear ring abuts against an inner peripheral wall of the cylinder body without forming a seal.

4. The utility model provides a synchronous oil pressure cylinder system of tandem type, its characterized in that, synchronous oil pressure cylinder system of tandem type includes a connecting pipe and two can the carminative oil pressure jar of any of claims 1 to 3, two can carminative oil pressure jar be first can carminative oil pressure jar and second can carminative oil pressure jar respectively, the both ends of this connecting pipe are connected respectively first can carminative oil pressure jar the top connection reach the second can carminative oil pressure jar the lower clutch, just the volume that the upper chamber of first can carminative oil pressure jar is used for holding hydraulic oil equals the volume that the lower chamber of second can carminative oil pressure jar is used for holding this hydraulic oil pressure.

5. The tandem synchronous oil hydraulic cylinder system of claim 4, wherein the cylinder body of the first de-airing oil hydraulic cylinder has a larger inner diameter than the cylinder body of the second de-airing oil hydraulic cylinder.