Hydraulic pressure linear adjusting and hydraulic pressure buffering device

Abstract

The invention discloses a hydraulic pressure linear adjusting and hydraulic pressure buffering device which is composed of a piston, a spring, a plug, a check ring and a matched sealing ring, and compared with the prior art, the hydraulic pressure linear adjusting and hydraulic pressure buffering device has the advantages that the buffering response time and the pressure stability control of the input end are better; and according to the Hooke's law, the change of the spring force is linear change, so that the pressure of the output end is ensured to be linear change, and the buffer has a hydraulic pressure linear adjustment function of a switch electromagnetic valve, which is not possessed by buffers on the market.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydraulic control, and particularly relates to a hydraulic pressure linear adjustment and hydraulic pressure buffering device. BACKGROUND

[0002] In a hydraulic control system, the outlet pressure control precision of an electromagnetic switch valve under high pressure (greater than 10 MPa) is poor, and the outlet pressure of the switch valve is not linear, which puts higher requirements on the control precision of a pressure control device (such as an ECU), but for a hydraulic execution unit with large rigidity and small liquid demand, even if the control precision of the ECU is very high, the pressure precision control requirement of the system cannot be met. According to the Bernoulli equation, the kinetic energy caused by the outlet pressure of the electromagnetic switch valve under high pressure cannot be avoided, which has an irreversible impact on the durability / lifetime of the hydraulic execution unit.

[0003] The existing buffer on the market is commonly composed of a piston rod and a spring, a piston cylinder and throttling, and a damping buffering structure. According to different combination types, a certain buffering effect is achieved. In principle, the effect of buffering and vibration absorption is adjusted according to the size of the throttle hole. Since the damping hole is a normally open structure, it cannot be switched and controlled. The structure can only play a buffering role and cannot achieve precise adjustment of hydraulic pressure. It is highly dependent on stable hydraulic pressure. If the hydraulic source is unstable (such as pressure pulses caused by flow pulsation), precise pressure adjustment at the input end cannot be achieved. Moreover, due to the size of the throttle hole, the response time is long, resulting in a long response time of the input end pressure. SUMMARY

[0004] In view of the above problems, the main purpose of the present application is to design a hydraulic pressure linear adjustment and hydraulic pressure buffering device to solve the problems of poor pressure control precision of the electromagnetic switch valve and non-linear pressure performance.

[0005] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows: A hydraulic pressure linear adjustment and hydraulic pressure buffering device, comprising a cylinder body, a piston is arranged at one end of the cylinder body, and the other end is closed by a plug; Wherein, an oil inlet and an oil outlet are arranged at the outer end of the piston, and an oil pipe channel is arranged at the upper part of the piston, the oil inlet and the oil outlet are communicated with the oil pipe channel respectively; A spring is arranged between the piston and the plug, the spring is sleeved outside the oil pipe channel, and a sealing ring is embedded in the outer periphery of the plug and the piston respectively, and the sealing ring is sealed in cooperation with the inner wall of the cylinder body.

[0006] As a further description of the present application, a retaining ring is arranged on the outside of the plug, the retaining ring is fixed with the end of the cylinder body, and the plug and the retaining ring limit the movement of the oil pipe channel.

[0007] As further described in the application, the oil inlet inputs high-pressure brake fluid, generates hydraulic pressure on the outer end of the piston, the piston acts upward, transmits the force to the spring, and the hydraulic pressure output by the oil outlet changes linearly.

[0008] As further described in the application, based on the setting of the cylinder diameter, spring stiffness, and spring pre-pressing force of the cylinder, the linear interval of the hydraulic pressure output by the oil outlet and the vibration impact absorbing force are determined.

[0009] As further described in the application, based on the setting of the cylinder diameter, spring stiffness, and spring pre-pressing force of the cylinder, the pressure accuracy of the electromagnetic switch valve under different hole diameters is adjusted.

[0010] Compared with the prior art, the technical effects of the application are: The application provides a hydraulic pressure linear adjustment and hydraulic pressure buffering device, which is composed of a piston, a spring, a plug, a check ring, and a matched sealing ring. The response time of the buffering and the pressure stability control of the input end are superior to those of the prior art. At the same time, due to the adoption of the piston, the spring, and other component structures, the spring force changes linearly according to Hooke's law, ensuring that the output end pressure changes linearly, so that the application has the hydraulic pressure linear adjustment function of the switch electromagnetic valve which is not possessed by the buffer on the market. BRIEF DESCRIPTION OF DRAWINGS

[0011] Fig. 1 It is a buffering device structure diagram of the application; Fig. 2 It is a pressure control curve diagram of the buffering device cooperating with the switch electromagnetic valve of the application.

[0012] In the figure, 1. piston, 11. oil inlet, 12. oil outlet, 2. plug, 3. spring, 4. sealing ring, 5. check ring, 6. oil pipe passage. DETAILED DESCRIPTION

[0013] The application will be described in detail below in combination with the drawings: In an embodiment of the application, a hydraulic pressure linear adjustment and hydraulic pressure buffering device is disclosed, referring to Figs. 1-2 The figure shows that the pressure control accuracy adjustment of the outlet of the electromagnetic switch valve under high pressure and the vibration impact buffering caused by high-pressure hydraulic pressure are provided, which adopts a piston 1, a plug 2, a spring 3, a sealing ring 4, and a check ring 5 to form a buffering body, and the buffering body is placed in a cylinder to form the buffering device of the embodiment.

[0014] The hydraulic pressure linear adjustment and hydraulic pressure buffering device mainly realizes the functions of linear adjustment and buffering of the pressure at the oil outlet 12 through energy transmission between hydraulic energy and mechanical energy. Specifically, the embodiment includes a cylinder body, one end of the cylinder body is provided with a piston 1, and the other end is closed through a plug 2; wherein the outer end of the piston 1 is provided with an oil inlet 11 and an oil outlet 12, and the upper part of the piston 1 is provided with an oil pipe passage 6, the oil inlet 11 and the oil outlet 12 are in communication with the oil pipe passage 6 respectively; a spring 3 is arranged between the piston 1 and the plug 2, the spring 3 is sleeved outside the oil pipe passage 6, and the plug 2 and the outer periphery of the piston 1 are respectively embedded with sealing rings 4, and the sealing rings 4 are sealed in cooperation with the inner wall of the cylinder body.

[0015] It should be further pointed out that the outer side of the plug 2 is provided with a check ring 5, the check ring 5 is fixed with the radial clamping groove of the cylinder body (the cylinder body is provided with the radial clamping groove, and the check ring 5 is clamped into the clamping groove to realize the fixation), and the plug 2 and the check ring 5 limit the movement of the oil pipe passage 6. The cooperation of the check ring 5 and the plug 2 has three effects: 1. limiting the oil pipe passage 6 and preventing the spring 3 from being pushed out of the cylinder body; 2. controlling the pre-pressure of the spring 3; 3. waterproof and dustproof for the outside.

[0016] In the pressure building process of the embodiment, high-pressure brake fluid is input through the oil inlet 11, the piston 1 is subjected to the hydraulic pressure generated by the brake fluid at the bottom of the piston 1, and thus moves upward and transmits the hydraulic pressure to the spring 3, at this time the spring 3 absorbs the hydraulic impact and moves upward at the same time, and the reaction force fed back to the piston 1 by the spring 3, that is, the hydraulic pressure at the oil outlet 12, changes linearly; similarly, in the pressure relief process, the piston 1 will retreat; therefore, the hydraulic pressure at the oil outlet 12 of the buffer changes linearly. The response time of the buffer and the stable control of the input pressure are superior to the prior art in principle; at the same time, the components such as the piston and the spring are used, according to Hooke's law, the change of the spring force is linear, that is, the change of the output pressure is also linear, so that the embodiment has the function of linear adjustment of the hydraulic pressure of the on-off electromagnetic valve. In the specific implementation process of the embodiment, the hydraulic pressure outputting linearly is fed back to another execution unit in the hydraulic system, the pressure output by the device is monitored through the pressure sensor, and thus the accurate control of the hydraulic pressure of the execution unit is realized.

[0017] Specifically, according to the above structural principle, the linear interval of the hydraulic pressure at the oil outlet at the bottom of the buffer, the pressure precision at the oil outlet, and the absorbed vibration impact force can be adjusted by adjusting the cylinder diameter of the cylinder, the stiffness of the spring, the pre-pressing force of the spring and other parameters. In particular, the pressure control precision of the on-off electromagnetic valve under different hole diameters can be adjusted according to different piston diameters, buffer spring strokes and other parameters. Among them, the embodiment needs to be used in combination with the electromagnetic valve. The current product throttle hole has no switching function, and the vibration absorption capacity and flow regulation capacity depend on the cylinder diameter and the spring stroke. After the control of the electromagnetic valve of the embodiment, the liquid amount entering the buffer is controllable, so as to realize the controllable pressure and high pressure regulation precision. At the same time, since the absorption liquid amount is controllable, the vibration impact caused by the structural principle is small.

[0018] For example: a 0.3mm diameter on-off electromagnetic valve, matched with a 15.8mm cylinder diameter, an 8mm spring stroke, a 136N / mm piston spring stiffness, and a spring pre-pressing force of 117N. Specifically, the pressure precision control process is as follows: 1. According to the 15.8mm cylinder diameter and the 8mm spring stroke, it can be known that the buffer variable volume V = 15.8*15.8*3.14 / 4*8 = 1.567ml; 2. According to the 0.3mm diameter on-off electromagnetic valve, the pressure difference (20MPa), and the flow coefficient Cq, the flow Q ≈ 8ml / s passing through the 0.3mm electromagnetic valve hole can be calculated (obtained according to the flow formula); 3. According to the flow and the buffer variable liquid amount demand, the time T = 1.567 / 8 = 0.195s required for the buffer stroke to be completed can be calculated; 4. If the adjustment frequency period T of the electromagnetic valve is 5ms, then about 195 / 5 ≈ 40 periods can be adjusted in the buffer pressure regulation process, which realizes the pressure control purpose of the on-off electromagnetic valve combined with the buffer.

[0019] The above is the process of realizing the pressure precision regulation of the buffer, and the control target pressure precision is realized, as shown in Fig. 2 The response time is less than 10ms, and the pressure control precision is within ±5%, which is beneficial to improve the pressure control precision of the output of the control unit part in the hydraulic system. Fig. 2 In the figure, the horizontal coordinate is time (unit: s), the vertical coordinate is pressure (unit: bar), the target pressure curve is the control target pressure curve regulated by the on-off electromagnetic valve combined with the buffer, the actual pressure curve is the actual pressure curve after the regulation of the on-off electromagnetic valve combined with the buffer, and the pressure control precision calculation method is | (actual pressure-target pressure) / target pressure |. Fig. 2The middle front end pressure rising section is a pressure increasing stroke, corresponding to the oil inlet action of the buffer; the middle section horizontal line part is a pressure maintaining process, corresponding to the process of the buffer spring not moving after compression; the rear end descending section is a pressure decreasing return stroke, corresponding to the oil return action of the buffer; the pressure take-off point part in the pressure increasing process is the spring pre-pressure of the buffer, and the take-off point can be adjusted according to the spring pre-pressure.

[0020] Through the above content, the technical scheme of the present application is disclosed, and the present application has the following advantages compared with the prior art. 1. The present application improves the stability of the buffer device by the cooperation of the plug and the check ring, and plays a protection role; 2. The present application adjusts the pressure control precision of the on-off electromagnetic valve under different hole diameters according to different piston cylinder diameters, spring stroke and other parameters, and has simple structure, easy realization, and economy and practicality; 3. The present application adjusts the linear variation interval of the output hydraulic pressure according to different spring K values and compression amounts, realizes the linear pressure performance of the outlet of the on-off valve, and is convenient to control.

[0021] The above examples are only used to illustrate the technical scheme of the present application but not limit the present application, and other modifications or equivalent replacements of the technical scheme of the present application made by those skilled in the art should be covered in the scope of the claims of the present application, as long as they do not deviate from the spirit and scope of the present application.

Claims

1. A hydraulic pressure linear adjustment and hydraulic pressure cushion device characterized by, The cylinder body is provided with a piston at one end and is closed at the other end by a plug; The outer end of the piston is provided with an oil inlet and an oil outlet, and the upper part of the piston is provided with an oil pipe channel, the oil inlet and the oil outlet being in communication with the oil pipe channel; A spring is arranged between the piston and the plug, the spring being sleeved outside the oil pipe channel, and the plug and the outer periphery of the piston are respectively embedded with sealing rings, the sealing rings being in sealing cooperation with the inner wall of the cylinder body.

2. The hydraulic force linear adjustment and hydraulic force cushioning device according to claim 1, characterized in that: The outer side of the plug is provided with a check ring, the check ring being fixed with the end of the cylinder body, and the plug and the check ring limiting the movement of the oil pipe channel.

3. The hydraulic force linear adjustment and hydraulic force cushioning device according to claim 1, characterized in that: The oil inlet inputs high-pressure brake fluid, generates hydraulic pressure on the outer end of the piston, and the piston acts upward to transmit the force to the spring, and the hydraulic pressure output by the oil outlet changes linearly.

4. The hydraulic force linear adjustment and hydraulic force cushioning device according to claim 3, characterized in that: Based on the setting of the cylinder diameter, spring stiffness and spring pre-pressure of the cylinder body, the linear interval of the hydraulic pressure output by the oil outlet and the absorption of the vibration impact force are determined.

5. The hydraulic force linear adjustment and hydraulic force cushioning device according to claim 3, characterized in that: Based on the setting of the cylinder diameter, spring stiffness and spring pre-pressure of the cylinder body, the pressure accuracy of the electromagnetic on-off valve under different hole diameters is adjusted.

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