CN102162475A - Pressure control valve with sensing function - Google Patents

Abstract

The invention discloses a pressure control valve with sensing function, which comprises a pilot valve body, the valve body is provided with a pilot control port and a low-pressure chamber, a valve core is arranged between the pilot control port and the low-pressure chamber, and the valve core is controlled by a feedback spring. The low-pressure chamber is provided with an oil drain port, and the low-pressure chamber is connected with a conversion joint with a through hole that communicates with it. The end of the conversion joint is provided with a pressure-regulating handle; A piston is set, one end of the piston is connected with the feedback spring, and the other end is connected with the pressure regulating handle through the pressure regulating spring, the contact surface of the pressure regulating spring and the piston is set with a positioning block, so that the inner step is between the positioning block and the piston; the conversion joint and A load pressure chamber is arranged on the contact surface of the piston, and a pressure surface capable of generating pressure on the pressure regulating spring is arranged on the piston surface inside. The invention automatically adjusts the pressure behind the valve by sensing the pressure change of the working load, so as to adapt to the size of the working load and avoid accidents of the actuator under the action of high-power driving force.

Description

A pressure control valve with sensing function

technical field

The invention relates to a pressure control valve with sensing function.

Background technique

Hydraulic machinery is widely used in engineering practice because of its good safety, high power and high efficiency, and hydraulic technology in hydraulic machinery is one of the key technologies to realize modern transmission and control. During the hydraulic work process, the work load increases, the driving oil pressure rises, and the corresponding actuator driving force increases, and the actuator is prone to accidents and accidents under the action of such a high-power driving force. Therefore, it is necessary to install a pressure control valve at the corresponding position to adjust the pressure behind the valve, reduce the driving oil pressure, reduce the driving force of the actuator, eliminate the axial impact load, reduce the load pressure, and prevent the actuator from driving under high power. Accidents occur under force. Most of the existing pressure control valves are fixed pressure control, that is, the control valve sets a fixed safety pressure. When the pressure behind the valve is greater than the safety pressure, the control valve is opened to relieve the pressure behind the valve. If the external environment affects Under certain circumstances or in special circumstances, the pressure behind the valve needs to be changed, and the controller can manually adjust the fixed safety pressure to meet the pressure demand. Such semi-automation requires the controller to monitor at any time, which is very inconvenient; and it is easy to produce errors when adjusting the safety pressure. affect its work. At present, there are few control valves on the market that can automatically adjust the pressure after the valve through the change of the working load pressure and then adapt to the size of the working load.

Contents of the invention

Aiming at the deficiencies of the above-mentioned prior art, the present invention provides a pressure control valve with sensing function, which can automatically adjust the pressure behind the valve by sensing the change of the working load, thereby adapting to the size of the working load and effectively solving the above-mentioned problems. Problems existing in the prior art.

In order to achieve the above object, the technical solution adopted by the present invention is: a pressure control valve with sensing function, comprising a pilot valve body, on which a pilot control port and a low-pressure chamber are arranged, the pilot control port and the low-pressure chamber There is a spool between the chambers, the spool is controlled by a feedback spring, the low-pressure chamber of the valve body is provided with a drain port, and a conversion joint with a through hole is included. One end of the conversion joint is connected to the valve body, and the other end is connected to the through hole. There is a pressure regulating handle inside;

The through hole of the conversion joint communicates with the low pressure chamber, and an inner step is arranged in the through hole, and the small hole section of the through hole is close to the low pressure chamber, and a piston is arranged in it, and one end of the piston is connected with the feedback spring, and the other end is connected to the low pressure chamber. The pressure regulating spring is connected with the pressure regulating handle, the feedback spring, the piston, the pressure regulating spring and the valve core are on the same center line, and a positioning block is arranged on the contact surface between the piston and the pressure regulating spring, and the positioning block is located on the inner step on, so that the position of the inner step is between the positioning block and the piston;

A load pressure chamber is provided on the contact surface between the conversion joint and the piston. The piston surface in the load pressure chamber is provided with a pressure surface that can generate pressure on the pressure regulating spring. A pressure oil hole is provided on the conversion joint. The oil hole communicates with the load pressure chamber.

As a preference: the outer surface of the conversion joint corresponding to the load pressure chamber is fixedly sleeved with a hinged joint, and the joint is provided with a pipe joint corresponding to the pressure hole.

As a preference: a gasket is provided between the hinged joint and the valve body.

As a preference: the pressure surface is an inclined surface.

As a preference: the load pressure chamber is arranged along the circumference of the outer surface of the piston, and the pressure surface on the piston is arranged along the circumference of the outer surface of the piston.

As a preference: the valve body is threadedly connected to the conversion joint, and the conversion joint and the pressure regulating handle.

As a preference: the piston has an oil collection groove arranged along the circumference of the piston near the positioning block, an oil return hole is arranged in the piston, and several oil through holes are arranged between the oil collection groove and the oil return hole.

As a preference: a spring seat is provided between the feedback spring and the piston, and the spring seat is fixedly connected to the end surface of the piston.

As a preference: an oil passage hole is also provided on the piston near the spring seat, and the oil passage hole communicates with the oil return hole in the piston.

Working principle: The load pressure enters the load pressure chamber from the pressure oil hole, which generates thrust on the pressure surface on the piston, and then drives the piston to move. When the pressure in the load pressure chamber is lower than one end value, the piston is affected by the tension of the pressure regulating spring, so that the positioning block is pressed against the inner step in the conversion joint, the feedback spring remains unchanged, and the pressure behind the valve remains constant; when the load pressure increases When it is high, the pressure regulating spring is compressed and shortened due to the movement of the piston, which makes the feedback spring stretch, the valve core is separated from the pilot control port, and the pressure oil in the pilot control port flows into the low-pressure chamber and returns oil from the drain port, thereby reducing the pressure of the valve. On the contrary, when the load pressure decreases, the pressure regulating spring expands to make the piston move, the feedback spring shortens, the pressure behind the valve increases, the spool reaches the pilot control port, the pressure behind the valve increases, and the load increases.

Compared with the prior art, the invention has the beneficial effects: the invention automatically adjusts the pressure behind the valve by sensing the pressure change of the work load, thereby adapting to the size of the work load and avoiding accidents of the actuator under the action of a high-power driving force.

Description of drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example:

Referring to Fig. 1, the pressure control valve with sensing function includes a pilot valve body 1 of a pressure reducing valve, on which a pilot control port 3 and a low-pressure chamber 2 are arranged, and the pilot control port 3 and the low-pressure chamber 2 Connected, and a spool 5 is set between the two to separate the pilot control port 3 from the low-pressure chamber 2, the spool 5 is controlled by the feedback spring 6, and the low-pressure chamber 2 of the valve body 1 is provided with a drain port 4 , also includes a conversion joint 7 with a through hole 11, one end of the conversion joint 7 is internally connected with the valve body 1, and the other end is provided with a pressure regulating handle 8 in the through hole 7, and the pressure regulating handle 8 is threadedly connected with the conversion joint 7 ;

The through hole 11 of the conversion joint 7 communicates with the low pressure chamber 2, and an inner step 13 is provided in the through hole 11, and the small hole section of the through hole 11 is close to the low pressure chamber 2, and a piston 9 is arranged in the small hole section One end of the piston 9 is connected to the feedback spring 6, and the other end is connected to the pressure regulating handle 8 through the pressure regulating spring 10. The feedback spring 6, the piston 9, the pressure regulating spring 10 and the spool 5 are on the same center line. A positioning block 12 is provided on the contact surface between the pressure spring 10 and the piston 9, and the positioning block 12 is located on the inner step 13, so that the position of the inner step 13 is between the positioning block 12 and the piston 9;

A load pressure chamber 14 is provided on the contact surface between the conversion joint 7 and the piston 9, and the load pressure chamber 14 is arranged along the outer circumference of the piston 9, and an adjustable pressure chamber is provided on the surface of the piston 9 in the load pressure chamber 14. The spring 10 produces a pressure surface 19, which is an inclined surface, and the outer surface of the piston 9 is arranged on the circumference. A pressure oil hole 15 is set on the adapter 7, and the pressure oil hole 15 communicates with the load pressure chamber 14.

The outer surface of the conversion joint 7 corresponding to the load pressure chamber 14 is fixedly covered with a hinged joint 20, and the jointed joint 20 is provided with a threaded pipe interface 18 corresponding to the pressure oil hole 15. Between the jointed joint 20 and the valve body 1 Gasket 17 is arranged between. One end of the hinged joint 20 away from the valve body 1 is threadedly connected with the conversion joint 7, and the other end is adjacent to the valve body, so that an interlock can be formed between the valve body 1, the conversion joint 7 and the hinged joint 20, which strengthens the transition. Connection of joint 7 to valve body 1.

Near the positioning block 12 of the piston 9, there is an oil collection groove 21 arranged along the circumference of the piston 9, an oil return hole 16 is arranged in the piston 9, and four oil through holes 22 are arranged between the oil collection groove 21 and the oil return hole 16, The direction of the oil return hole 16 close to the positioning block 12 is blocked by the positioning block 12 .

A spring seat 23 is arranged between the feedback spring 6 and the piston 9, and the spring seat 23 is fixedly connected to the end face of the piston 9, and four oil holes 22 are also arranged near the position near the spring seat 23 on the piston 9. 22 links to each other with the oil return hole 16 in the piston 9.

During work, the load pressure oil circuit is connected to the load pressure chamber 19 through the pipe interface 18 on the hinge joint 20 . First press the pressure regulating handle 8, adjust the screw-in depth of the conversion joint 7, so that the pressure reaches the maximum working pressure of the actuator, and then adjust the pressure regulating handle 8, so that once the pressure in the load pressure chamber 19 rises, the valve body 1 The pressure behind the valve begins to drop, and the corresponding critical pressure value at this time is the starting pressure of the pressure control valve.

The load pressure enters the load pressure chamber 19 from the pressure oil hole 15 , and generates thrust on the pressure surface 19 on the piston 9 , thereby driving the piston 9 to move. When the pressure in the load pressure chamber 19 is lower than one end value, that is, the starting pressure, the piston 9 is affected by the tension of the pressure regulating spring 10, so that the positioning block 12 is pressed against the inner step 13 in the adapter 7, the feedback spring 6 remains unchanged, and the valve The pressure behind the valve of body 1 remains constant; when the load pressure rises, the pressure regulating spring 10 is compressed and shortened due to the movement of the piston 9, so that the feedback spring 6 relaxes, the spool 5 is separated from the pilot control port 3, and the inside of the pilot control port 3 The pressure oil flows into the low-pressure chamber 2 and returns to the oil from the drain port 4, thereby reducing the pressure after the valve, and then performing load reduction; on the contrary, when the load pressure decreases, the pressure regulating spring 10 expands to make the piston 9 move, and the feedback The spring 6 shortens, the pressure behind the valve body 1 increases, the valve core 5 reaches the pilot control port 3, the pressure behind the valve increases, and the execution load increases.

For the load pressure chamber 14 formed between the conversion joint 7 and the piston 9, because the piston 9 moves in the conversion joint 7, a small amount of load oil in it may leak to both ends. From the oil hole 22, the oil return hole 16 to the low pressure chamber 2, and then return the oil from the oil drain port 4; the oil leaked to the positioning block 12 to the oil sump 21, and flows through the oil hole 22, the oil return hole 16 To the low-pressure chamber 2, and finally return the oil through the drain port 4.

When the piston 9 moves, the load pressure chamber 14 can directly lubricate the surface of the piston 9 with oil; it can also return the oil flowing from the pilot control port 3 to the low-pressure chamber 2 to the oil return hole 16, the oil passage hole 22, and finally to the piston. 9 surface, to achieve lubrication.

The above descriptions are only detailed descriptions and drawings of the preferred embodiments of the present invention, and are not intended to limit the present invention. All similarly changed embodiments or similar structures made according to the creative spirit of the present invention should be included in the scope of the present invention. middle.

Claims (9)

1. A pressure control valve with a sensing function, comprising a pilot valve body, on which a pilot control port and a low-pressure chamber are arranged, a spool is arranged between the pilot control port and the low-pressure chamber, and the spool passes through Feedback spring control, the low-pressure chamber of the valve body is provided with an oil drain port, which is characterized in that it also includes a conversion joint with a through hole, one end of the conversion joint is connected to the valve body, and the other end is provided with a pressure regulating handle in the through hole; The through hole of the conversion joint communicates with the low pressure chamber, and an inner step is arranged in the through hole, and the small hole section of the through hole is close to the low pressure chamber, and a piston is arranged in it, and one end of the piston is connected with the feedback spring, and the other end is connected to the low pressure chamber. The pressure regulating spring is connected with the pressure regulating handle, the feedback spring, the piston, the pressure regulating spring and the valve core are on the same center line, and a positioning block is arranged on the contact surface between the piston and the pressure regulating spring, and the positioning block is located on the inner step on, so that the position of the inner step is between the positioning block and the piston; A load pressure chamber is provided on the contact surface between the conversion joint and the piston. The piston surface in the load pressure chamber is provided with a pressure surface that can generate pressure on the pressure regulating spring. A pressure oil hole is provided on the conversion joint. The oil hole communicates with the load pressure chamber. 2. A pressure control valve with sensing function according to claim 1, characterized in that: the outer surface of the conversion joint corresponding to the load pressure chamber is fixed with a hinge joint, and the joint joint is provided with a pressure hole Corresponding pipe interface. 3. A pressure control valve with sensing function according to claim 2, characterized in that: a sealing gasket is provided between the hinged joint and the valve body. 4. A pressure control valve with a sensing function according to claim 1, wherein the pressure surface is an inclined surface. 5. A pressure control valve with sensing function according to claim 1 or 4, characterized in that: the load pressure chamber is arranged along the circumference of the outer surface of the piston, and the pressure surface on the piston is arranged along the circumference of the outer surface of the piston. 6. A pressure control valve with sensing function according to claim 1, characterized in that: the valve body is connected to the adapter, and the adapter and the pressure regulating handle are threadedly connected. 7. A pressure control valve with sensing function according to claim 1, characterized in that: there is an oil collection groove arranged along the circumference of the piston near the positioning block near the piston, an oil return hole is arranged in the piston, and an oil return hole is arranged between the oil collection groove and the piston. There are several oil through holes between the oil return holes. 8 . The pressure control valve with sensing function according to claim 1 , wherein a spring seat is provided between the feedback spring and the piston, and the spring seat is fixedly connected to the end surface of the piston. 9. A pressure control valve with sensing function according to claim 8, characterized in that: the piston is also provided with an oil hole near the spring seat, and the oil hole is connected with the return in the piston. The oil holes are connected.

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