CN108443269B

CN108443269B - Unidirectional speed limiting device

Info

Publication number: CN108443269B
Application number: CN201810244288.5A
Authority: CN
Inventors: 方正; 方策; 梅胜楷; 吴武通
Original assignee: Zhejiang Canaan Technology Ltd
Current assignee: Zhejiang Canaan Technology Ltd
Priority date: 2018-03-23
Filing date: 2018-03-23
Publication date: 2023-07-28
Anticipated expiration: 2038-03-23
Also published as: CN108443269A

Abstract

The invention relates to a unidirectional speed limiting device, which comprises a valve body and a valve core, wherein a first connecting port, a second connecting port and a valve port are arranged on the valve body, the valve core can slide along the axis direction of the valve core to open or close the valve port so as to enable the first connecting port and the second connecting port to be communicated or disconnected, a piston cavity is arranged in the valve body, a piston matched with the piston cavity is arranged in the valve core in an outward protruding manner, the inner cavity of the valve body is divided into a first fluid cavity and a second fluid cavity by the piston and the valve port, the first connecting port is communicated with the first fluid cavity, the valve port is communicated with the second connecting port, a fluid channel with flow resistance larger than the valve port is arranged in the valve body, the fluid channel is communicated with the second connecting port and the second fluid cavity, an inclined plane or a curved plane inclined to the sliding direction of the valve core is arranged in the first fluid cavity, and an elastic piece is arranged between the piston and the valve body. The method is used for controlling the flow rate in the hydraulic system, and fills the blank of the self-adaptive current-limiting switch of the hydraulic system.

Description

Unidirectional speed limiting device

Technical Field

The invention relates to a unidirectional speed limiting device.

Background

The existing hydraulic pipeline is generally provided with a pipeline explosion-proof valve, and when the hydraulic pipeline is broken and blasted, the pipeline explosion-proof valve can block the hydraulic pipeline to prevent the hydraulic actuating mechanism and oil in the hydraulic pipeline from being discharged outwards, so that the hydraulic actuating mechanism stops working. The existing pipeline explosion-proof valve can realize the closing function based on the fact that the large pressure difference exists at the two ends of the valve conveniently, is very insensitive to flow velocity reaction and even has no reaction, and does not have any reaction when leakage is caused by small cracks of an oil pipe or looseness of an oil pipe joint, and the flow velocity is increased to 3 times of the normal working flow velocity. According to the related industry standard, the maximum speed of the hydraulic lifting mechanism cannot exceed 3 times of the working speed, and the existing pipeline explosion-proof valve obviously cannot meet the requirements.

Disclosure of Invention

The present invention addresses the above-described problems by providing a one-way speed limiting device.

The technical scheme adopted by the invention is as follows: the utility model provides a unidirectional speed limiting device, includes valve body, case, be equipped with first connector, second connector, valve port on the valve body, the case slides along case axle center direction and can open or close the valve port and make first connector, second connector communicate with each other or break off, be equipped with the piston chamber in the valve body, the case outwards protruding be equipped with the piston of piston chamber adaptation, the valve body inner chamber is separated into first fluid chamber, second fluid chamber by piston and valve port, first connector and first fluid chamber keep communicating, the valve port communicates first fluid chamber and second connector, be equipped with in the valve body be equipped with the fluid channel that the flow resistance is greater than the valve port in the valve body, fluid channel intercommunication second connector and second fluid chamber, the case outer wall is equipped with inclined plane or curved surface that inclines to the case slip direction in first fluid chamber, be equipped with the elastic component between piston and the valve body.

One end of the valve core, which is close to the valve port, is conical.

An adaptive conical inner wall is arranged in the valve body corresponding to the cone.

The valve body is connected with an adjusting screw in a threaded mode, and the adjusting screw stretches into the second fluid cavity.

The elastic piece is a spring, and two ends of the spring respectively prop against the piston and the valve body.

The beneficial effects of the invention are as follows: by arranging the inclined plane or the curved surface, the static pressure direction of the fluid is changed, so that the acting force of the inclined plane or the curved surface along the sliding direction of the valve core is smaller than the acting force of the inclined plane or the curved surface along the moving direction of the valve core; by arranging the fluid channel with larger flow resistance, static pressure difference appears at the two ends of the piston at the moment of valve port flow change. Therefore, when the pipeline of the hydraulic system is leaked or damaged and the valve port flow exceeds the set value, the device can close the oil way, and the system stops running. The operating personnel can find the problem in the first time, can avoid a large amount of leakage of hydraulic oil. The method is used for controlling the flow rate in the hydraulic system, and fills the blank of the self-adaptive current-limiting switch of the hydraulic system.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a schematic structural view of the valve core in fig. 1.

In the figure, 1, a valve body; 101, a first connection interface; 102, a second connection port; 103, valve port; 104, a fluid channel; 105, a tapered inner wall; 106, a first fluid chamber; 107, a second fluid chamber; 2, a valve core; 201, a piston; 203, a bevel or a curved surface; 3, a piston cavity; 4, an elastic piece; and 5, adjusting a screw.

Detailed Description

The invention will be better illustrated with reference to the following drawings and specific examples.

The utility model provides a unidirectional speed limiting device, includes valve body 1, case 2, be equipped with first connector 101, second connector 102, valve port 103 on the valve body 1, case 2 slides along case 2 axle center direction and can open or close valve port 103 and make first connector 101, second connector 102 communicate with each other or break off, be equipped with piston chamber 3 in the valve body 1, case 2 outwards protruding be equipped with piston 201 of piston chamber 3 adaptation, valve body 1 inner chamber is separated into first fluid chamber 106, second fluid chamber 107 by piston 201 and valve port 103, first connector 101 keeps communicating with first fluid chamber 106, valve port 103 communicates first fluid chamber 106 and second connector 102, be equipped with in the valve body 1 fluid channel 104 that is greater than valve port 103 is equipped with in the valve body 1, fluid channel 104 communicates second connector 102 and second fluid chamber 107, the case 2 outer wall is equipped with inclined plane or curved surface 203 that inclines to the case 2 direction in first fluid chamber 106, be equipped with elastic component 4 between piston 201 and the valve body 1, the elastic component is compression spring, has the downward thrust to the piston.

According to the static pressure transmission principle (the static pressure of the static oil is equal to the pressure born by any point in the static oil, the static pressure direction of the oil is always perpendicular to the pressure bearing surface), and the acting force acting on the inclined plane along the sliding direction of the valve core is F=P×S×a (the magnitude of a is related to the inclination of the inclined plane); the force acting on the plane in the spool sliding direction is f=p×s. When the pressures at the two ends of the piston are equal, the acting force acting on the piston plane and sliding along the valve core is smaller than the sum of the acting force acting on the piston inclined plane and sliding along the valve core and the restoring force of the compression spring. The piston is therefore stationary in the top column section. The valve port opens to a set maximum value. When the flow rate of the valve port suddenly increases, the pressure generated by the fluid in a fluid system is smaller as the flow rate is higher according to the Bernoulli theorem, so that the static pressure born by the piston at one end of the first fluid cavity is instantaneously reduced. However, the fluid passage 104 communicating the second connection port 102 and the second fluid chamber 107 forms a large liquid resistance to the fluid. So that the static pressure experienced by the flat end of the piston is not significantly reduced at the same time as the static pressure experienced by the beveled end of the piston is reduced. When the static pressure born by the plane end of the piston exceeds the sum of the static pressure born by the inclined surface end of the piston and the restoring force of the spring, the piston moves towards the valve port to close the valve port. By this arrangement, the sensitivity of the flow restriction device to flow changes is greatly increased. Therefore, the device is sensitive in reflection, can realize unidirectional speed limit on the hydraulic elevator, and can close the oil port when the flow exceeds the set maximum value, so that the safety and reliability of the elevator are ensured.

The fluid passage 104 may increase the flow resistance by decreasing the inner diameter, increasing the length, providing tortuous locations, etc.

The end of the valve core 2 near the valve port 103 is conical. The magnitude of a can be calculated by the slope of the conical surface, and the sensitivity can be controlled as desired.

An adapted conical inner wall 105 is arranged in the valve body 1 corresponding to the cone shape. When the valve port is closed, the first cone 203 is attached to the cone inner wall 105, so that the acting force of fluid is reduced, the pressure maintaining effect of the second connection port is facilitated, and the maintenance is convenient, quick and safe after the oil way is in a problem. Moreover, the hydraulic oil leakage caused by pipeline damage or loose oil pipe joints can be avoided, and resource waste and environmental pollution are avoided.

The valve body 1 is connected with an adjusting screw 5 in a threaded manner, and the adjusting screw 5 extends into the second fluid cavity 107. When the adjusting screw 5 stretches into the second fluid cavity 107 to prop against the valve core 2, the distance between the valve core and the valve port can be changed by rotating the adjusting screw, and the opening degree of the valve port can be adjusted, so that the working flow rate can be adjusted conveniently and reliably.

The elastic member 4 is a spring, and two ends of the spring respectively support against the piston 201 and the valve body 1. The elastic member 4 is a cylindrical compression spring. When the pressure of the first connection port 101 is equal to the pressure of the second connection port 102, that is, the oil path is in a normal state, the valve port is kept open by the spring.

In hydraulic hoist, oil circuit pipeline lug connection hydro-cylinder, when oil circuit pipeline appears revealing, the oil in the hydro-cylinder can flow back the oil circuit pipeline, can the crack flow from the breach of oil circuit pipeline, if do not notice this moment, have in the hydro-cylinder can waste, more serious can form serious pollution in high cleanliness work places such as pharmacy, food, seriously influence production and product, in addition, when personnel stand in hydraulic hoist below, have the risk of forming casualties. When the device is installed on a hydraulic lifting machine, the first connecting port 101 is connected with an oil way pipeline, the second connecting port 102 is connected with an oil cylinder, when the oil way pipeline leaks, the static pressure of the first connecting port 101 is rapidly reduced, oil in the oil cylinder can flow back to the first connecting port 101 through the second connecting port 102, the flow speed is suddenly accelerated, the device can be rapidly closed, the hydraulic lifting machine can stop running, and a worker can detect abnormality to check. The device can also be used for other hydraulic oil ways with higher sensitivity for flow rate control.

The foregoing is merely one embodiment of the present invention, and is not intended to limit the scope of the present invention; the protection scope of the present invention is defined by the claims in the claims, and all equivalent changes and modifications made in accordance with the invention are within the protection scope of the present patent.

Claims

1. The utility model provides a unidirectional speed limiting device, includes valve body (1), case (2), be equipped with first connector (101), second connector (102), valve port (103) on valve body (1), case (2) slide along case (2) axle center direction and can open or close valve port (103) and make first connector (101), second connector (102) communicate with each other or break off its characterized in that: the valve is characterized in that a piston cavity (3) is arranged in the valve body (1), a piston (201) matched with the piston cavity (3) is arranged on the outer bulge of the valve core (2), the inner cavity of the valve body (1) is divided into a first fluid cavity (106) and a second fluid cavity (107) by the piston (201) and a valve port (103), the first connecting port (101) is communicated with the first fluid cavity (106), the valve port (103) is communicated with the first fluid cavity (106) and the second connecting port (102), a fluid channel (104) with flow resistance larger than the valve port (103) is arranged in the valve body (1), the fluid channel (104) is communicated with the second connecting port (102) and the second fluid cavity (107), an inclined surface or a curved surface (203) inclined to the sliding direction of the valve core (2) is arranged in the first fluid cavity (106) on the outer wall of the valve core (2), and an elastic piece (4) is arranged between the piston (201) and the valve body (1).

2. A unidirectional speed limiting device as claimed in claim 1, wherein: one end of the valve core (2) close to the valve port (103) is conical.

3. A unidirectional speed limiting device as claimed in claim 2, wherein: an adaptive conical inner wall (105) is arranged in the valve body (1) corresponding to the cone shape.

4. A unidirectional speed limiting device according to any one of claims 1 to 3, wherein: an adjusting screw (5) is connected to the valve body (1) in a threaded mode, and the adjusting screw (5) stretches into the second fluid cavity (107).

5. A unidirectional speed limiting device according to any one of claims 1 to 3, wherein: the elastic piece (4) is a spring, and two ends of the spring respectively prop against the piston (201) and the valve body (1).