CN205190187U - Oil pump relief valve - Google Patents

Abstract

The utility model discloses an oil pump relief valve, including valve body, case, spring and screw jam, be equipped with the oil duct in the valve body, case and spring dress are in the oil duct, and the screw stops up through the screw fixedly bottom the valve body, and the case side wall surface is equipped with the draining through -hole. Adopt the utility model discloses, product simple structure can reduce the speed of opening, closing of case, reduces the knocking noise, reducing the case and receiving the fluctuation of high pressure chest oil pressure and the vibration velocity and the frequency of production, reduction oil pump noise improves engine NVH quality.

Description

oil pump relief valve

technical field

The utility model belongs to the technical field of engines, in particular to a pressure relief valve of an engine oil pump.

Background technique

The oil pump relief valve of the engine is a device to stabilize the outlet pressure of the oil pump. When the outlet pressure reaches a certain limit, the pressure relief valve opens to allow a part of the oil to flow back to the oil inlet or oil pan to achieve stable oil pressure. The role of protecting hydraulic components.

The common pressure relief valve is composed of valve body, valve core, spring and thread plug, which divide the oil passage into three chambers: high pressure chamber, oil return chamber and valve core chamber. In the initial state, the thread plug and the valve body are fixed through threaded connection, and the spring is preloaded and compressed. The valve core is pressed by the spring force, and its top is pressed against the sealing surface of the valve body, so that the high pressure chamber is separated from the oil return chamber. When the oil pressure in the high-pressure chamber is high enough, the engine oil pushes open the spool, so that the high-pressure chamber communicates with the oil return chamber to generate pressure relief, so as to ensure that the pumping pressure of the oil pump is within a certain safe range. However, the oil pressure in the high-pressure chamber is affected by the engine speed and the pumping performance of the oil pump itself, which will produce high-frequency vibrations. When the oil pressure vibration range is near the initial pre-tightening force of the spring, the valve core will be displaced back and forth. The body produces high-frequency percussion, which produces abnormal noise and reduces the quality of use.

Utility model content

In order to solve the above problems, the utility model provides a pressure relief valve structure with a simple structure, which can reduce the knocking noise of the valve core.

The technical scheme of the utility model is:

A pressure relief valve for an oil pump, comprising a valve core, a spring, a threaded plug and a valve body, the valve body is provided with a valve hole, the valve core and the spring are installed in the valve hole, and the side wall of the valve core is provided with an oil drain passage hole, the bottom of the valve hole is equipped with a threaded plug.

Further, four oil drain holes are equidistantly arranged on the side wall of the valve core.

Further, the oil drain hole is a circular through hole.

In the oil pump pressure relief valve of the utility model, since an oil drain hole is added on the side of the spool, the oil return cavity is connected with the spool cavity, and the spool cavity is filled with engine oil. When the pressure in the high-pressure chamber suddenly increases, the valve core is pressed and moves in the opening direction, the volume of the valve core cavity decreases, and the oil flows from the valve core cavity to the oil return cavity. Due to its own viscosity, the oil flows in the opposite direction to the displacement of the valve core. Damping, counteracting part of the pressure in the high-pressure chamber to prevent the valve core from opening too quickly. On the contrary, when the pressure in the high-pressure chamber suddenly decreases, the spool moves toward the closing direction due to the elastic force of the spring, the volume of the spool chamber increases, and the oil flows from the oil return chamber to the spool chamber, and the oil flow generates a pulling force, which offsets part of the spring force and prevents the valve from closing. Core closes too quickly. In this way, the speed of opening and closing of the valve core can be reduced, and knocking noise can be reduced. In special cases, the damping of oil flow will filter out a certain degree of oil pressure vibration and reduce the knocking frequency of the spool.

Description of drawings

Fig. 1 is a schematic structural diagram of a pressure relief valve in the background technology.

Fig. 2 is a structural schematic diagram of the pressure relief valve of the present invention.

Fig. 3 is a structural schematic diagram of the valve core of the present invention.

In Figure 1, 1-1 is the original valve core, 1-2 is the original spring, 1-3 is the original valve body, 1-4 is the original thread blockage; 1-A is the original high pressure chamber, 1-B is the original oil return chamber , 1-C is the original spool cavity.

In Fig. 2, 1 is a valve core, 2 is a spring, 3 is a thread plug, 4 is a valve body, 41 is a valve hole, A is a high-pressure chamber, B is an oil return chamber, and C is a valve core chamber.

Among Fig. 3, 11 is valve core drain hole.

detailed description

Below in conjunction with accompanying drawing and embodiment the utility model is described further.

Figure 1 is a common pressure relief valve, which is composed of the original valve body 1-3, the original valve core 1-1, the original spring 1-2, and the original thread plug 1-4, which divide the oil passage into three chambers Chamber: the original high pressure chamber 1-A, the original oil return chamber 1-B and the original spool chamber 1-C.

Figures 2 and 3 show the oil pump pressure relief valve proposed by the utility model, which includes a valve core 1, a spring 2, a thread plug 3 and a valve body 4. There is an oil passage 41 in the valve body 4, and the valve core 1 and the spring 2 are installed. In the oil passage 41, the thread plug 3 is installed at the bottom of the oil passage 41, thereby forming a high-pressure oil chamber A, an oil return chamber B, and a valve core chamber C; four oil drain holes 11 are equidistantly arranged on the side wall of the valve core 1, and the drain The oil hole 11 is a circular through hole, the diameter of which depends on the strength of the valve core 1 and the required oil drain area. The oil drain hole 11 connects the oil return chamber B with the valve core chamber C.

Its working principle is as follows: an oil drain hole 11 is added on the side of the spool 1 to make the oil return chamber B communicate with the spool chamber C, and the spool chamber C is filled with oil. When the spool 1 is in the closed state, it is opened under the action of high oil pressure in the high-pressure chamber A, the volume of the spool chamber C decreases, and the oil in the spool chamber C flows to the oil return chamber B through the oil drain hole 11, and the oil flow is generated with the valve The opposite damping of core movement offsets part of the pressure of high-pressure chamber A and prevents valve core 1 from opening too quickly; when valve core 1 is in the open state, the oil pressure of high-pressure chamber A decreases, and valve core 1 closes under the force of spring 2 , the volume of the spool cavity increases, and the engine oil flows from the oil return cavity B back to the spool cavity C through the oil drain hole 11, and the reverse damping generated by the engine oil offsets part of the spring force to prevent the spool 1 from closing too quickly. In this way, the vibration speed and frequency of the valve core 1 caused by the oil pressure fluctuation of the high pressure chamber A can be reduced, the noise of the oil pump can be reduced, and the NVH quality of the engine can be improved.

Claims (3)

1. An oil pump pressure relief valve, including a valve body, a valve core, a spring and a threaded plug, the valve body is provided with an oil passage, the valve core and the spring are installed in the oil passage, and the threaded plug is fixed to the bottom of the valve body through the thread, and they will The oil passage is divided into three chambers: a high-pressure chamber, an oil return chamber and a valve core chamber; the feature is that: the side wall of the valve core is provided with an oil drain through hole, which communicates with the oil return chamber and the valve core chamber. 2 . The oil pump pressure relief valve according to claim 1 , wherein four oil discharge holes are equidistantly arranged on the side wall of the valve core. 3 . 3. The oil pump pressure relief valve according to claim 2, characterized in that: the oil relief hole is a circular through hole.