Anti-creep and anti-slip plunger cylinder

Abstract

The application discloses an anti-crawling and anti-sliding plunger cylinder, which can avoid the low-speed shaking and crawling problem in the rising process and the falling and sliding problem. The anti-crawling and anti-sliding plunger cylinder comprises a cylinder barrel, a plunger assembly, a one-way valve and the like. The plunger assembly comprises a plunger and a plunger rod, and divides the inner cavity of the cylinder barrel into a rod cavity and a rodless cavity. The plunger comprises a plunger body, an oil gap is arranged between the plunger body and the inner wall of the cylinder barrel, a support ring is fixed on the plunger body and is in sliding connection with the cylinder barrel, an oil passing gap is arranged on the support ring, the oil gap and the oil passing gap form a throttling channel, the throttling channel is in communication with the rod cavity and the rodless cavity. The plunger rod is hollow to form a plunger rod inner cavity, a communication hole is arranged on the side surface of the plunger rod, and the communication hole is in communication with the plunger rod inner cavity, the rod cavity and the rodless cavity. The one-way valve is arranged in the plunger rod inner cavity between the communication hole and the rodless cavity. In the rising process of the plunger assembly, the one-way valve is closed. In the falling process of the plunger assembly, the one-way valve is opened.

Description

Technical Field

[0001] This invention relates to the field of hydraulic cylinder technology, specifically to an anti-creep and anti-slip piston cylinder. Background Technology

[0002] Existing plunger cylinders are typically designed with two interconnected chambers (i.e., a rod chamber and a rodless chamber connected), for example, Chinese Patent Publication No. CN221442990U, entitled "A Plunger Cylinder Structure." According to the plunger cylinder principle calculation formula, PS equals (the sum of G, F, and P1S1). Wherein, P represents system pressure; S represents the cross-sectional area of ​​the plunger; G represents the weight of the hydraulic cylinder load; F represents the frictional force between the plunger and the cylinder block; P1 represents the back pressure of the rod cavity; S1 represents the annular cross-sectional area of ​​the rod cavity.

[0003] In actual operation, in a conventional two-chamber piston cylinder, the back pressure difference between the rod chamber and the rodless chamber is very small, almost identical, while the load gravity is usually constant. Therefore, friction has a significant impact on the stability of the system. For long-stroke piston cylinders, due to structural design limitations, the piston rod stability is poor. In addition, the coaxiality and straightness control of the cylinder barrel and piston rod are difficult, resulting in increased variation in the lateral force of the piston, which in turn increases the friction. When the piston cylinder is lifted, low-speed shaking and crawling may occur.

[0004] While simply reducing the flow rate through the through-hole can increase the back pressure in the rod chamber, reduce the impact of friction on the piston cylinder, and improve the cylinder's crawling performance, the reduced flow rate in the oil supply circuit during the cylinder's descent can prevent the oil from being replenished to the rod chamber in time, leading to a slippage during descent.

[0005] In view of this, how to design a piston cylinder that can avoid low-speed jitter and crawling during ascent and also avoid slippage during descent has become an urgent problem to be solved in the hydraulic cylinder market. Summary of the Invention

[0006] The purpose of this invention is to provide a piston cylinder that can avoid both low-speed shaking and crawling problems during ascent and slippage during descent.

[0007] The technical solution of this invention is: An anti-creep and anti-slip piston cylinder, comprising: Cylinder; A plunger assembly, including a plunger and a plunger rod, divides the cylinder cavity into a rod-side chamber and a rodless chamber; One-way valve; The plunger includes: The plunger body has an oil passage gap between it and the inner wall of the cylinder. A support ring is fixed on the plunger body and slidably connected to the cylinder. The support ring has an oil passage notch. The oil passage gap and the oil passage notch form a throttling channel. The throttling channel connects the rod chamber and the rodless chamber. The plunger rod is hollow inside to form a plunger rod cavity, and a connecting hole is provided on the side of the plunger rod, which connects the plunger rod cavity, the rod cavity and the rodless cavity; The one-way valve is located inside the plunger rod cavity between the connecting hole and the rodless cavity; During the rise of the plunger assembly, the check valve closes; During the descent of the plunger assembly, the one-way valve opens. The specific operation of one type of anti-creep and anti-slip plunger cylinder in this solution is as follows: When the plunger assembly rises, the check valve closes. At this time, the plunger rod cavity between the connecting hole and the rodless cavity is cut off and closed (the oil in the rod cavity cannot enter the rodless cavity through the connecting hole and the plunger rod cavity). The oil in the rod cavity can only enter the rodless cavity through the throttling channel. During the process of the oil passing through the throttling channel, it encounters a suddenly narrowed cross section, forming a throttling phenomenon, which increases the back pressure in the rod cavity and weakens the influence of friction. This effectively eliminates the problem of low-speed shaking and crawling during the rise of the plunger assembly, and achieves a smooth rise of the plunger assembly.

[0008] When the plunger assembly descends, the one-way valve opens, allowing oil in the rodless chamber to quickly enter the rod chamber through the plunger rod cavity and the connecting hole. This enables rapid oil return and a quick response, ensuring a smooth descent of the plunger assembly and preventing slippage during descent. Therefore, an anti-creep and anti-slippage plunger cylinder can avoid both low-speed vibration and creeping issues during ascent and slippage during descent.

[0009] Preferably, the check valve includes: The valve body has an inner cavity and is fixed inside the inner cavity of the plunger rod. Its lower end is provided with an oil passage hole for the valve body. The valve ball is located inside the valve body cavity; A baffle is located at the upper end of the valve body. It has a valve ball limiting hole and a baffle oil passage hole. The valve ball limiting hole is located in the middle of the baffle. During the upward movement of the plunger assembly, the valve ball descends and presses against the upper port of the oil passage in the valve body, at which point the check valve closes. During the descent of the plunger assembly, the valve ball rises and is contained within the valve ball limiting hole, at which point the check valve opens. The specific operation of the check valve in this design is as follows: During the upward movement of the plunger assembly, the oil in the rod chamber is squeezed, increasing the oil pressure in the rod chamber. At this time, the valve ball will descend under its own weight and the oil pressure in the rod chamber until it touches the upper port of the valve body oil passage, thereby closing the check valve.

[0010] During the descent of the plunger assembly, the oil in the rodless chamber is squeezed, increasing the oil pressure in the rodless chamber. At this time, the valve ball will rise under the action of the oil pressure in the rodless chamber (overcoming the weight of the valve ball) until the valve ball is pressed against the valve ball limiting hole. The oil can then pass through the valve body oil passage, the valve body cavity and the baffle oil passage, thereby putting the check valve in the open state.

[0011] Preferably, the inner wall of the plunger rod cavity is provided with a stepped surface and an inner retaining ring. The stepped surface is located between the connecting hole and the rodless cavity, and the inner retaining ring is located below the stepped surface. The baffle and valve body are limited between the stepped surface and the inner retaining ring, and the upper end of the valve body cavity is open. This facilitates the installation, disassembly, and replacement of the one-way valve.

[0012] Preferably, there are two support rings, distributed along the cylinder axial direction with a gap between them, and each support ring has the aforementioned oil passage notch. The axial distribution of the two support rings not only improves the sliding stability of the plunger, thus enhancing the lifting stability of the plunger assembly, but also allows the oil in the rod chamber to first enter the oil passage gap between the two support rings through the oil passage notch on the upper support ring during the plunger assembly's ascent, achieving a first-stage throttling effect. Then, the oil in the oil passage gap enters the rodless chamber through the oil passage notch on the lower support ring, achieving a second-stage throttling effect. This further increases the back pressure in the rod chamber, reduces the influence of friction, and effectively eliminates the problem of low-speed vibration and creep during the plunger assembly's ascent, achieving a smooth rise of the plunger assembly.

[0013] Preferably, the oil passage notch on the support ring near the rod chamber constitutes a primary throttling orifice, and the oil passage notch on the support ring near the rodless chamber constitutes a secondary throttling orifice. The primary and secondary throttling orifices are staggered along the circumference of the cylinder, and the width of the primary throttling orifice is greater than the width of the secondary throttling orifice. During the piston assembly's ascent, the oil in the rod chamber first enters the oil passage gap between the two support rings through the primary throttling orifice, achieving a primary throttling phenomenon. Then, the oil in the oil passage gap enters the rodless chamber through the secondary throttling orifice, achieving a secondary throttling phenomenon. Because the primary and secondary throttling orifices are staggered along the circumference of the cylinder, and the width of the primary throttling orifice is greater than the width of the secondary throttling orifice, the throttling effect of both primary and secondary throttling phenomena can be improved, further increasing the back pressure in the rod chamber and reducing the influence of friction. This effectively eliminates the problem of low-speed vibration and creep during the piston assembly's ascent, achieving a smooth ascent of the piston assembly.

[0014] Preferably, the oil passage is an annular gap with a width of 0.3-1 mm.

[0015] Preferably, the width of the oil passage notch is 3-10 mm.

[0016] Preferably, the connecting hole and the rod cavity are located on the same side of the plunger body, and the connecting hole is close to the plunger body.

[0017] Preferably, the top of the cylinder is provided with a sealed guide sleeve, through which the plunger rod passes, and the plunger rod and the guide sleeve are slidably and sealed together. This improves the smooth lifting and lowering performance of the plunger assembly.

[0018] Preferably, the bottom of the cylinder is provided with a sealed base, and the base is provided with an oil inlet.

[0019] The beneficial effects of this invention are: When the plunger assembly rises, the check valve closes, and the oil in the rod chamber can only enter the rodless chamber through the throttling channel, forming a throttling phenomenon. This increases the back pressure in the rod chamber, reduces the influence of friction, and enables the plunger assembly to rise smoothly, thereby effectively eliminating the problem of low-speed shaking and crawling during the rise of the plunger assembly.

[0020] When the plunger assembly descends, the check valve opens, and the oil in the rodless chamber can quickly enter the rod chamber through the plunger rod cavity and the connecting hole, achieving rapid oil return and rapid response, thus ensuring a smooth descent of the plunger assembly and avoiding the problem of the plunger assembly sliding down during descent. Attached Figure Description

[0021] Figure 1 This is a cross-sectional structural diagram of an anti-creep and anti-slip piston cylinder according to the present invention.

[0022] Figure 2 This is a schematic diagram of a support ring structure according to the present invention.

[0023] Figure 3 This is a cross-sectional structural diagram of the valve body of the present invention.

[0024] Figure 4 This is a schematic diagram of one structure of the baffle of the present invention.

[0025] In the picture: Cylinder 1; 2. Plunger, 2.1. Plunger body, 2.2. Support ring; Piston rod 3; Rod cavity 4; Rodless cavity 5; Throttling channel 6, oil passage clearance 6.1, oil passage notch 6.2; One-way valve 7, valve body 7.1, valve ball 7.2, baffle 7.3, valve body cavity 7.4, valve body oil passage hole 7.5, valve ball limit hole 7.6, baffle oil passage hole 7.7; 8. Piston rod inner cavity; 9-hole connector; Guide sleeve 10; Base 11, oil inlet 11.1. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Specific Implementation Example 1, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, an anti-creep and anti-slip piston cylinder includes a cylinder barrel 1, a piston assembly, and a one-way valve 7. The cylinder barrel 1 extends vertically.

[0027] The plunger assembly includes a plunger 2 and a plunger rod 3, which divides the inner cavity of the cylinder 1 into a rod chamber 4 and a rodless chamber 5. The plunger rod 3 extends upward above the cylinder 1.

[0028] The plunger 2 includes a plunger body 2.1 and a support ring 2.2. An oil passage gap 6.1 is provided between the plunger body 2.1 and the inner wall of the cylinder 1. The support ring 2.2 is fixed to the plunger body 2.1. The support ring 2.2 is in close contact with the inner wall of the cylinder 1 and is slidably connected to the cylinder 1. An oil passage notch 6.2 is provided on the support ring 2.2, which passes through the support ring 2.2 axially along the plunger 2. The oil passage gap 6.1 and the oil passage notch 6.2 form a throttling channel 6. The throttling channel 6 connects the rod chamber 4 and the rodless chamber 5.

[0029] The plunger rod 3 is hollow inside, forming a plunger rod cavity 8. A connecting hole 9 is provided on the side of the plunger rod 3. The connecting hole 9 connects the plunger rod cavity 8, the rod cavity 4, and the rodless cavity 5. Specifically, the connecting hole 9 connects the rod cavity 4 and the plunger rod cavity 8, and the plunger rod cavity 8 connects to the rodless cavity 5, thereby connecting the plunger rod cavity 8, the rod cavity 4, and the rodless cavity 5 through the connecting hole 9.

[0030] The one-way valve 7 is located in the inner cavity 8 of the plunger rod between the connecting hole 9 and the rodless cavity 5.

[0031] During the upward movement of the plunger assembly, the one-way valve 7 is closed. Specifically, during the upward movement of the plunger assembly, the oil pressure in the rod chamber 4 increases. At this time, the one-way valve 7 is closed, and the oil in the rod chamber 4 cannot enter the rodless chamber 5 through the connecting hole 9 and the plunger rod cavity 8.

[0032] During the descent of the plunger assembly, the one-way valve 7 opens. Specifically, during the descent of the plunger assembly, the oil pressure in the rodless chamber 5 increases. At this time, the one-way valve 7 opens, and the oil in the rodless chamber 5 can quickly enter the rod chamber 4 through the plunger rod inner cavity 8 and the connecting hole 9, achieving rapid oil return.

[0033] The specific operation of an anti-creep and anti-slip piston cylinder in this embodiment is as follows. When the plunger assembly rises, the one-way valve 7 closes. At this time, the plunger rod cavity 8 between the connecting hole 9 and the rodless cavity 5 is cut off and closed (the oil in the rod cavity 4 cannot enter the rodless cavity 5 through the connecting hole 9 and the plunger rod cavity 8). The oil in the rod cavity 4 can only enter the rodless cavity 5 through the throttling channel 6. During the process of the oil passing through the throttling channel 6, it encounters a suddenly narrowed cross section, forming a throttling phenomenon, which increases the back pressure of the rod cavity 4 and weakens the influence of friction. This effectively eliminates the problem of low-speed shaking and crawling during the rise of the plunger assembly, and realizes the smooth rise of the plunger assembly.

[0034] When the plunger assembly descends, the one-way valve 7 opens, allowing the oil in the rodless chamber 5 to quickly enter the rod chamber 4 through the plunger rod cavity 8 and the connecting hole 9. This enables rapid oil return and a quick response, ensuring a smooth descent of the plunger assembly and preventing it from sliding down during descent. Therefore, this anti-creep and anti-slip plunger cylinder avoids both the low-speed shaking and creeping problems during ascent and the sliding problems during descent.

[0035] Specific embodiment two, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, an anti-creep and anti-slip piston cylinder includes a cylinder barrel 1, a piston assembly, and a one-way valve 7. The cylinder barrel 1 extends vertically. In this embodiment, the cylinder barrel 1 is vertically positioned. A sealed base 11 is provided at the bottom of the cylinder barrel 1. Specifically, the cylinder barrel 1 and the base 11 are connected by bolts, threads, or welding, and a sealing ring is provided between the cylinder barrel 1 and the base 11. An oil inlet 11.1 is provided on the base 11.

[0036] The plunger assembly includes a plunger 2 and a plunger rod 3, which are integrated. The plunger assembly divides the inner cavity of the cylinder 1 into a rod chamber 4 and a rodless chamber 5. The rod chamber 4 is located above the rodless chamber 5. The oil inlet 11.1 communicates with the rodless chamber 5. The plunger rod 3 extends upwards above the cylinder 1. Specifically, the top of the cylinder 1 is provided with a sealing guide sleeve 10, which is connected to the cylinder 1 by bolts, threads, or welding. A sealing ring is provided between the guide sleeve 10 and the cylinder 1. The plunger rod 3 passes through the guide sleeve 10, and the plunger rod 3 and the guide sleeve 10 are in a sliding sealing connection. This improves the smooth lifting and lowering performance of the plunger assembly.

[0037] The plunger 2 includes a plunger body 2.1 and a support ring 2.2. An oil passage gap 6.1 is provided between the plunger body 2.1 and the inner wall of the cylinder 1. In this embodiment, the oil passage gap 6.1 is an annular gap, and the width of the oil passage gap 6.1 is 0.3-1 mm. The oil passage gap 6.1 can be selected according to the specifications of the plunger cylinder. For example, the width of the oil passage gap 6.1 is 0.75 mm (that is, the outer diameter of the plunger body 2.1 is 1.5 mm smaller than the inner diameter of the cylinder 1).

[0038] The support ring 2.2 is fixed to the plunger body 2.1. Specifically, the plunger body 2.1 has an annular groove, and the support ring 2.2 is engaged in the annular groove to fix the support ring 2.2 to the plunger body 2.1. The support ring 2.2 is in close contact with the inner wall of the cylinder 1, and the support ring 2.2 is slidably connected to the cylinder 1. The support ring 2.2 has an oil passage notch 6.2, which passes through the support ring 2.2 axially along the plunger 2. The oil passage gap 6.1 and the oil passage notch 6.2 form a throttling channel 6. The throttling channel 6 connects the rod chamber 4 and the rodless chamber 5.

[0039] In this embodiment, the width of the oil passage notch 6.2 is 3-10 mm. The width of the oil passage notch 6.2 can be selected according to the specifications of the plunger cylinder. For example, the width of the oil passage notch 6.2 is 5 mm.

[0040] The plunger rod 3 passes through the plunger body 2.1. The plunger rod 3 is hollow inside, forming a plunger rod cavity 8. The lower end of the plunger rod cavity 8 is open and communicates with the rodless cavity 5. A connecting hole 9 is provided on the side of the plunger rod 3. The connecting hole 9 connects the plunger rod cavity 8, the rod cavity 4, and the rodless cavity 5. Specifically, the connecting hole 9 connects the rod cavity 4 and the plunger rod cavity 8, and the plunger rod cavity 8 connects the rodless cavity 5, thereby connecting the plunger rod cavity 8, the rod cavity 4, and the rodless cavity 5. In this embodiment, the connecting hole 9 and the rod cavity 4 are located on the same side of the plunger body 2.1, and the connecting hole 9 is close to the plunger body 2.1.

[0041] The one-way valve 7 is located in the inner cavity 8 of the plunger rod between the connecting hole 9 and the rodless cavity 5.

[0042] During the upward movement of the plunger assembly, the one-way valve 7 is closed. Specifically, during the upward movement of the plunger assembly, the oil pressure in the rod chamber 4 increases. At this time, the one-way valve 7 is closed, and the oil in the rod chamber 4 cannot enter the rodless chamber 5 through the connecting hole 9 and the plunger rod cavity 8.

[0043] During the descent of the plunger assembly, the one-way valve 7 opens. Specifically, during the descent of the plunger assembly, the oil pressure in the rodless chamber 5 increases. At this time, the one-way valve 7 opens, and the oil in the rodless chamber 5 can quickly enter the rod chamber 4 through the plunger rod inner cavity 8 and the connecting hole 9, achieving rapid oil return.

[0044] In this embodiment, the one-way valve 7 includes a valve body 7.1, a valve ball 7.2, and a baffle 7.3. The valve body 7.1 is fixed inside the plunger rod cavity 8. The valve body 7.1 has an inner cavity 7.4, which is open at the upper end in this embodiment. An oil passage 7.5 is provided at the lower end of the valve body 7.1. The oil passage 7.5 connects the rodless cavity 5 and the inner cavity 7.4. The valve ball 7.2 is located inside the inner cavity 7.4. In this embodiment, the valve ball 7.2 is a steel ball. However, the valve ball 7.2 can also be a plastic ball, a ceramic ball, or another metal ball. The baffle 7.3 is located at the upper end of the valve body 7.1, and it seals the upper opening of the inner cavity 7.4. The baffle 7.3 has a valve ball limiting hole 7.6 and a baffle oil passage 7.7. The valve ball limiting hole 7.6 is located in the middle of the baffle 7.3.

[0045] In one example, the edge of the valve ball limiting hole 7.6 is provided with one or more circumferentially evenly distributed oil passages, which constitute the baffle oil passage 7.7.

[0046] In another example, the valve ball limiting hole 7.6 is located in the middle of the baffle 7.3, and the baffle oil passage hole 7.7 is distributed on the baffle 7.3 outside the valve ball limiting hole 7.6.

[0047] During the upward movement of the plunger assembly, the valve ball 7.2 descends and abuts against the upper port of the valve body oil passage 7.5, at which point the one-way valve 7 closes. During the downward movement of the plunger assembly, the valve ball 7.2 rises and is limited within the valve ball limiting hole 7.6, at which point the one-way valve 7 opens.

[0048] The specific operation of the one-way valve 7 in this embodiment is as follows. During the upward movement of the plunger assembly, the oil in the rod chamber 4 is squeezed, and the oil pressure in the rod chamber 4 increases. At this time, the valve ball 7.2 will descend under its own weight and the oil pressure in the rod chamber 4 until the valve ball 7.2 abuts against the upper port of the valve body oil passage 7.5, thereby putting the one-way valve 7 in the closed state.

[0049] During the descent of the plunger assembly, the oil in the rodless chamber 5 is squeezed, increasing the oil pressure in the rodless chamber 5. At this time, the valve ball 7.2 will rise under the action of the oil pressure in the rodless chamber 5 (overcoming the weight of the valve ball 7.2) until the valve ball 7.2 is pressed against the valve ball limiting hole 7.6. The oil can then pass through the valve body oil passage 7.5, the valve body cavity 7.4, and the baffle oil passage 7.7, thereby putting the check valve 7 in the open state.

[0050] The specific operation of an anti-creep and anti-slip piston cylinder in this embodiment is as follows. When the plunger assembly rises, the one-way valve 7 closes. At this time, the plunger rod cavity 8 between the connecting hole 9 and the rodless cavity 5 is cut off and closed (the oil in the rod cavity 4 cannot enter the rodless cavity 5 through the connecting hole 9 and the plunger rod cavity 8). The oil in the rod cavity 4 can only enter the rodless cavity 5 through the throttling channel 6. During the process of the oil passing through the throttling channel 6, it encounters a suddenly narrowed cross section, forming a throttling phenomenon, which increases the back pressure of the rod cavity 4 and weakens the influence of friction. This effectively eliminates the problem of low-speed shaking and crawling during the rise of the plunger assembly, and realizes the smooth rise of the plunger assembly.

[0051] When the plunger assembly descends, the one-way valve 7 opens, allowing the oil in the rodless chamber 5 to quickly enter the rod chamber 4 through the plunger rod cavity 8 and the connecting hole 9. This enables rapid oil return and a quick response, ensuring a smooth descent of the plunger assembly and preventing it from sliding down during descent. Therefore, this anti-creep and anti-slip plunger cylinder avoids both the low-speed shaking and creeping problems during ascent and the sliding problems during descent.

[0052] Furthermore, the inner wall of the plunger rod cavity 8 is provided with a stepped surface and an inner retaining ring. The stepped surface is located between the connecting hole 9 and the rodless cavity 5, and the inner retaining ring is located below the stepped surface. The baffle 7.3 and the valve body 7.1 are limited between the stepped surface and the inner retaining ring. This facilitates the installation, disassembly, and replacement of the one-way valve 7.

[0053] Specific embodiment three, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, an anti-creep and anti-slip piston cylinder includes a cylinder barrel 1, a piston assembly, and a one-way valve 7. The cylinder barrel 1 extends vertically. In this embodiment, the cylinder barrel 1 is vertically positioned. A sealed base 11 is provided at the bottom of the cylinder barrel 1. Specifically, the cylinder barrel 1 and the base 11 are connected by bolts, threads, or welding, and a sealing ring is provided between the cylinder barrel 1 and the base 11. An oil inlet 11.1 is provided on the base 11.

[0054] The plunger assembly includes a plunger 2 and a plunger rod 3, which are integrated. The plunger assembly divides the inner cavity of the cylinder 1 into a rod chamber 4 and a rodless chamber 5. The rod chamber 4 is located above the rodless chamber 5. The oil inlet 11.1 communicates with the rodless chamber 5. The plunger rod 3 extends upwards above the cylinder 1. Specifically, the top of the cylinder 1 is provided with a sealing guide sleeve 10, which is connected to the cylinder 1 by bolts, threads, or welding. A sealing ring is provided between the guide sleeve 10 and the cylinder 1. The plunger rod 3 passes through the guide sleeve 10, and the plunger rod 3 and the guide sleeve 10 are in a sliding sealing connection. This improves the smooth lifting and lowering performance of the plunger assembly.

[0055] The plunger 2 includes a plunger body 2.1 and a support ring 2.2. An oil passage gap 6.1 is provided between the plunger body 2.1 and the inner wall of the cylinder 1. In this embodiment, the oil passage gap 6.1 is an annular gap, and the width of the oil passage gap 6.1 is 0.3-1 mm. The oil passage gap 6.1 can be selected according to the specifications of the plunger cylinder. For example, the width of the oil passage gap 6.1 is 0.75 mm (that is, the outer diameter of the plunger body 2.1 is 1.5 mm smaller than the inner diameter of the cylinder 1).

[0056] The support ring 2.2 is fixed to the plunger body 2.1. Specifically, the plunger body 2.1 has an annular groove, and the support ring 2.2 is engaged in the annular groove to fix the support ring 2.2 to the plunger body 2.1. The support ring 2.2 is in close contact with the inner wall of the cylinder 1, and the support ring 2.2 is slidably connected to the cylinder 1. The support ring 2.2 has an oil passage notch 6.2, which passes through the support ring 2.2 axially along the plunger 2. The oil passage gap 6.1 and the oil passage notch 6.2 form a throttling channel 6. The throttling channel 6 connects the rod chamber 4 and the rodless chamber 5.

[0057] In this embodiment, the width of the oil passage notch 6.2 is 3-10 mm. The width of the oil passage notch 6.2 can be selected according to the specifications of the plunger cylinder. For example, the width of the oil passage notch 6.2 is 5 mm.

[0058] The plunger rod 3 passes through the plunger body 2.1. The plunger rod 3 is hollow inside, forming a plunger rod cavity 8. The lower end of the plunger rod cavity 8 is open and communicates with the rodless cavity 5. A connecting hole 9 is provided on the side of the plunger rod 3. The connecting hole 9 connects the plunger rod cavity 8, the rod cavity 4, and the rodless cavity 5. Specifically, the connecting hole 9 connects the rod cavity 4 and the plunger rod cavity 8, and the plunger rod cavity 8 connects the rodless cavity 5, thereby connecting the plunger rod cavity 8, the rod cavity 4, and the rodless cavity 5. In this embodiment, the connecting hole 9 and the rod cavity 4 are located on the same side of the plunger body 2.1, and the connecting hole 9 is close to the plunger body 2.1.

[0059] The one-way valve 7 is located in the inner cavity 8 of the plunger rod between the connecting hole 9 and the rodless cavity 5.

[0060] During the upward movement of the plunger assembly, the one-way valve 7 is closed. Specifically, during the upward movement of the plunger assembly, the oil pressure in the rod chamber 4 increases. At this time, the one-way valve 7 is closed, and the oil in the rod chamber 4 cannot enter the rodless chamber 5 through the connecting hole 9 and the plunger rod cavity 8.

[0061] During the descent of the plunger assembly, the one-way valve 7 opens. Specifically, during the descent of the plunger assembly, the oil pressure in the rodless chamber 5 increases. At this time, the one-way valve 7 opens, and the oil in the rodless chamber 5 can quickly enter the rod chamber 4 through the plunger rod inner cavity 8 and the connecting hole 9, achieving rapid oil return.

[0062] In this embodiment, the check valve 7 is a conventional check valve 7 (not shown in the drawings). For example, it can be a spring-loaded check valve 7 that uses the elasticity of an internal spring to prevent reverse flow; or a diaphragm check valve 7 composed of a rubber diaphragm. As long as the oil pressure in the rod chamber 4 increases when the plunger assembly rises, the check valve 7 can automatically close; when the oil pressure in the rodless chamber 5 increases when the plunger assembly falls, the check valve 7 can automatically open.

[0063] The specific operation of an anti-creep and anti-slip piston cylinder in this embodiment is as follows. When the plunger assembly rises, the one-way valve 7 closes. At this time, the plunger rod cavity 8 between the connecting hole 9 and the rodless cavity 5 is cut off and closed (the oil in the rod cavity 4 cannot enter the rodless cavity 5 through the connecting hole 9 and the plunger rod cavity 8). The oil in the rod cavity 4 can only enter the rodless cavity 5 through the throttling channel 6. During the process of the oil passing through the throttling channel 6, it encounters a suddenly narrowed cross section, forming a throttling phenomenon, which increases the back pressure of the rod cavity 4 and weakens the influence of friction. This effectively eliminates the problem of low-speed shaking and crawling during the rise of the plunger assembly, and realizes the smooth rise of the plunger assembly.

[0064] When the plunger assembly descends, the one-way valve 7 opens, allowing the oil in the rodless chamber 5 to quickly enter the rod chamber 4 through the plunger rod cavity 8 and the connecting hole 9. This enables rapid oil return and a quick response, ensuring a smooth descent of the plunger assembly and preventing it from sliding down during descent. Therefore, this anti-creep and anti-slip plunger cylinder avoids both the low-speed shaking and creeping problems during ascent and the sliding problems during descent.

[0065] Furthermore, the inner wall of the plunger rod cavity 8 is provided with a stepped surface and an inner retaining ring. The stepped surface is located between the connecting hole 9 and the rodless cavity 5, and the inner retaining ring is located below the stepped surface. The one-way valve 7 is limited between the stepped surface and the inner retaining ring. This facilitates the installation, disassembly, and replacement of the one-way valve 7.

[0066] In this specific embodiment four, the remaining structure is the same as in specific embodiment one, two, or three, except that... In this embodiment, as Figure 1As shown, there are two support rings 2.2, which are distributed along the axial direction of the cylinder 1 (i.e., upper and lower support rings 2.2). There is a gap between the two support rings 2.2. Both support rings 2.2 are provided with the oil passage notch 6.2. Two support rings 2.2 are distributed along the axial direction of the cylinder 1. They not only improve the sliding stability of the plunger 2, thereby improving the lifting stability of the plunger assembly, but also have oil passage notches 6.2 on both support rings 2.2. Thus, during the rising process of the plunger assembly, the oil in the rod chamber 4 first enters the oil passage gap 6.1 between the two support rings 2.2 through the oil passage notch 6.2 on the upper support ring 2.2, achieving a first-stage throttling phenomenon. Then, the oil in the oil passage gap 6.1 enters the rodless chamber 5 through the oil passage notch 6.2 on the lower support ring 2.2, achieving a second-stage throttling phenomenon. This further increases the back pressure in the rod chamber 4 and reduces the influence of friction, thereby effectively eliminating the problem of low-speed shaking and crawling during the rising process of the plunger assembly and achieving a smooth rising of the plunger assembly.

[0067] In this embodiment, the annular slots correspond one-to-one with the support rings 2.2, and the support rings 2.2 are engaged in the corresponding annular slots.

[0068] Furthermore, the oil passage notch 6.2 on the support ring 2.2 near the rod chamber 4 constitutes a primary throttling orifice, and the oil passage notch 6.2 on the support ring 2.2 near the rodless chamber 5 constitutes a secondary throttling orifice. The primary and secondary throttling orifices are staggered along the circumference of the cylinder 1, and the width of the primary throttling orifice is greater than the width of the secondary throttling orifice. During the piston assembly's ascent, the oil in the rod chamber 4 first enters the oil passage 6.1 between the two support rings 2.2 through the primary throttling orifice, achieving a primary throttling phenomenon. Then, the oil in the oil passage 6.1 enters the rodless chamber 5 through the secondary throttling orifice, achieving a secondary throttling phenomenon. Since the primary and secondary throttling orifices are staggered along the circumference of the cylinder 1, and the width of the primary throttling orifice is greater than that of the secondary throttling orifice, the throttling effect of the primary and secondary throttling phenomena can be improved, further increasing the back pressure in the rod chamber 4 and reducing the influence of friction. This effectively eliminates the problem of low-speed vibration and crawling during the piston assembly's ascent, achieving a smooth ascent of the piston assembly.

[0069] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An anti-creep and anti-slip piston cylinder, comprising: Cylinder; A plunger assembly, including a plunger and a plunger rod, divides a cylinder bore into a rod-side chamber and a rodless chamber; characterized in that it further includes a one-way valve. The plunger includes: The plunger body has an oil passage gap between it and the inner wall of the cylinder. A support ring is fixed on the plunger body and slidably connected to the cylinder. The support ring has an oil passage notch. The oil passage gap and the oil passage notch form a throttling channel. The throttling channel connects the rod chamber and the rodless chamber. The plunger rod is hollow inside to form the plunger rod cavity, and the plunger rod side is provided with a connecting hole that connects the plunger rod cavity, the rod cavity and the rodless cavity; The check valve is located inside the plunger rod cavity between the connecting hole and the rodless cavity; During the rise of the plunger assembly, the check valve closes; During the descent of the plunger assembly, the check valve opens.

2. The anti-creep and anti-slip piston cylinder according to claim 1, characterized in that, The one-way valve includes: The valve body has an inner cavity and is fixed inside the inner cavity of the plunger rod. Its lower end is provided with an oil passage hole for the valve body. A valve ball is located inside the body cavity of the valve body; A baffle is provided at the upper end of the valve body, and a valve ball limiting hole and a baffle oil passage hole are provided thereon, with the valve ball limiting hole located in the middle of the baffle; During the upward movement of the plunger assembly, the valve ball descends and abuts against the upper port of the oil passage in the valve body, at which point the one-way valve closes. During the descent of the plunger assembly, the valve ball rises and is confined within the valve ball limiting hole, at which point the one-way valve opens.

3. The anti-creep and anti-slip piston cylinder according to claim 2, characterized in that, The inner wall of the plunger rod cavity is provided with a stepped surface and an inner retaining ring. The stepped surface is located between the connecting hole and the rodless cavity. The inner retaining ring is located below the stepped surface. The baffle and the valve body are limited between the stepped surface and the inner retaining ring. The upper end of the valve body cavity is open.

4. A creep-resistant and slip-resistant plunger cylinder according to claim 1, 2, or 3, characterized in that, There are two support rings, which are distributed along the axial direction of the cylinder and have a gap between them. Both support rings are provided with oil passage notches.

5. The anti-creep and anti-slip piston cylinder according to claim 4, characterized in that, The oil passage notch on the support ring near the rod chamber forms a primary throttle orifice, and the oil passage notch on the support ring near the rodless chamber forms a secondary throttle orifice. The primary throttle orifice and the secondary throttle orifice are staggered along the circumference of the cylinder, and the width of the primary throttle orifice is greater than the width of the secondary throttle orifice.

6. A creep-resistant and slip-resistant plunger cylinder according to claim 1, 2, or 3, characterized in that, The oil passage gap is an annular gap, and the width of the oil passage gap is 0.3-1 mm.

7. A creep-resistant and slip-resistant plunger cylinder according to claim 1, 2, or 3, characterized in that, The width of the oil passage notch is 3-10 mm.

8. A creep-resistant and slip-resistant plunger cylinder according to claim 1, 2, or 3, characterized in that, The connecting hole and the rod cavity are located on the same side of the plunger body, and the connecting hole is close to the plunger body.

9. A creep-resistant and slip-resistant plunger cylinder according to claim 1, 2, or 3, characterized in that, The top of the cylinder is provided with a sealed guide sleeve, through which the plunger rod passes, and the plunger rod is slidably and sealed to the guide sleeve.

10. A creep-resistant and slip-resistant plunger cylinder according to claim 1, 2, or 3, characterized in that, The cylinder has a sealed base at the bottom, and the base has an oil inlet.

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