CN110206921A - A kind of engine oil pump pressure-limiting valve with damping hole - Google Patents

Abstract

A pressure-limiting valve for an oil pump with a damping hole, relating to the technical field of oil pumps, the pressure-limiting valve includes a valve hole, a spring and a plunger arranged in the valve hole, and a feedback oil port and an oil discharge port are opened on the wall of the valve hole The plunger consists of a first cylindrical part, a rod-shaped part and a second cylindrical part from top to bottom. A transfer chamber is formed between the rod-shaped part and the wall of the valve hole, and the second cylindrical part and the wall of the valve hole A feedback oil chamber is formed between the bottoms of the holes, and a damping hole connecting the transfer chamber and the feedback oil chamber is opened at the junction of the second cylindrical part and the rod-shaped part. When the oil pressure at the oil outlet of the oil pump is too high, the oil outlet The feedback oil can enter the feedback oil chamber through the feedback oil port, the transfer chamber and the damping hole in sequence, and push the plunger to overcome the elastic force of the spring and move upward until the first cylindrical part moves away from the position blocked by the oil drain port, so that the feedback oil The oil port and drain port communicate through the transfer chamber. The oil pump pressure limiting valve with a damping hole of the present invention has a simple structure and low processing difficulty, and can effectively reduce the pressure fluctuation of feedback oil.

Description

Oil pump pressure limiting valve with damping hole

technical field

The invention relates to the technical field of oil pumps, in particular to an oil pump pressure limiting valve with a damping hole.

Background technique

The oil pump pressure limiting valve can be divided into two types: pump outlet feedback and main channel feedback according to the source of feedback oil. As shown in Figure 1, the traditional oil pump pressure limiting valve for pump outlet feedback includes a valve hole, a spring 1 and a plunger 2 arranged in the valve hole, and feedback oil ports are respectively opened in the lower and middle parts of the valve hole wall. 3 and the oil drain port 4, the feedback oil port 3 communicates with the oil outlet of the oil pump, the oil drain port 4 communicates with the oil inlet of the oil pump, the plunger 2 includes a cylindrical part and a rod-shaped part 2b, and one end of the spring 1 It is connected to the top of the valve hole, and the other end is installed in the cylindrical part. One end of the rod-shaped part 2b is connected to the bottom end of the cylindrical part, and the other end is in contact with the bottom of the valve hole. Between the rod-shaped part 2b and the hole wall of the valve hole A transfer chamber 5 is formed between them. When the oil pressure of the oil outlet of the oil pump is too high, the feedback oil at the oil outlet can enter the transfer chamber 5 through the feedback oil port 3, pushing the plunger 2 to overcome the elastic force of the spring 1 and move upward. , until the cylindrical part moves away from the position blocked by the oil drain port 4, so that the feedback oil port 3 communicates with the oil drain port 4 through the transfer chamber 5. This kind of oil pump with feedback from the pump outlet will impact the pressure limiting valve due to large fluctuations in the outlet pressure of the pump, resulting in unstable opening pressure of the pressure limiting valve. Especially for the pressure limiting valve with limited space structure and high spring stiffness, its instability is even more amplified. In order to reduce the influence of this instability on oil pressure regulation, the traditional method is to open a damping hole on the pump body of the oil pump. However, since the diameter of the damping hole is very small, usually between 1-2mm, and the damping hole It needs to be installed inside the pump body, so it is not convenient to process, and the cutter will be easily broken because it is too long and too thin. Generally speaking, the method of setting damping holes on the pump body to reduce pressure fluctuations is limited.

Contents of the invention

The object of the present invention is to provide a pressure limiting valve of an oil pump with a damping hole. The pressure limiting valve has a simple structure and low processing difficulty, and can effectively reduce the pressure fluctuation of feedback oil.

In order to solve the above technical problems, the present invention adopts the following technical solutions: a pressure limiting valve for an oil pump with a damping hole, including a valve hole, a spring and a plunger arranged in the valve hole, the middle part of the valve hole wall and the The lower part is respectively provided with a feedback oil port and an oil drain port. The plunger includes a first cylindrical part and a rod-shaped part. One end of the spring is connected to the top of the valve hole, and the other end is installed in the first cylindrical part. One end of the rod-shaped part is connected to the bottom end of the first cylindrical part, and a transition chamber is formed between the rod-shaped part and the hole wall of the valve hole, and it is characterized in that: the plunger also includes a A feedback oil chamber is formed between the second cylindrical part and the bottom of the valve hole, and a communication relay is opened at the connection between the second cylindrical part and the rod-shaped part. chamber and the damping hole of the feedback oil chamber, when the oil pressure at the oil outlet of the oil pump is too high, the feedback oil at the oil outlet can enter the feedback oil chamber through the feedback oil port, the transfer chamber and the damping hole in turn, pushing the plunger to overcome The elastic force of the spring moves upward until the first cylindrical part moves away from the position blocked by the oil drain port, so that the feedback oil port and the oil drain port are communicated through the transfer chamber.

Further, the first cylindrical part is a cylindrical body with an opening facing upwards, and the second cylindrical part is a cylindrical body with an opening facing downwards.

Furthermore, the damping hole includes a first through hole transversely penetrating through the rod-shaped portion and a second through hole vertically connected to the first through hole, the upper end of the second through hole communicates with the first through hole, and the lower end of the second through hole communicates with the first through hole. The feedback oil cavity is connected, and the diameter of the first through hole is larger than the diameter of the second through hole.

Furthermore, the damping hole also includes a third through hole whose diameter gradually increases from top to bottom, the upper end of the third through hole communicates with the lower end of the second through hole, and the lower end of the third through hole communicates with the lower end of the second through hole. The feedback oil chamber is connected.

Preferably, the joints between the rod-shaped portion and the first cylindrical portion and the second cylindrical portion are inclined-plane structures.

Compared with the traditional oil pump pressure limiting valve, the oil pump pressure limiting valve with damping hole of the present invention only adds a second cylindrical part on the plunger, and the second cylindrical part and the rod-shaped part A damping hole is opened on the pump body. This structure is very simple. Compared with drilling damping holes inside the pump body, the present invention can also simplify the pump body structure and reduce the processing difficulty. A feedback oil cavity is formed between the second cylindrical part of the pressure limiting valve of the present invention and the hole wall of the valve hole, and the feedback oil cavity communicates with the transfer chamber through a damping hole, that is, it is connected with the feedback oil port and the oil outlet of the oil pump. When the feedback oil from the oil outlet of the oil pump reaches the transfer chamber through the feedback oil port, the feedback oil will enter the feedback oil chamber through the damping hole. At this time, the plunger will not only receive the pressure of the feedback oil in the transfer chamber, but also It will receive the pressure of the feedback oil in the feedback oil chamber. Since the second cylindrical part and the first cylindrical part are respectively located at the two ends of the rod-shaped part, the feedback oil in the transfer chamber Pressure is exerted on the opposite end surfaces, and the two pressures are in opposite directions and cancel each other out, while the feedback oil in the feedback oil chamber only exerts pressure on the second cylindrical part, and this pressure can push the plunger to move upward against the elastic force of the spring , until the pressure limiting valve is opened. It is not difficult to see from the above that the pressure limiting valve in the present invention does not directly drive the plunger to move by the oil at the oil outlet, but pushes the plunger to move through the feedback oil in the feedback oil chamber. During this process, the oil outlet When the oil from the transfer chamber enters the feedback oil chamber through the damping hole, the damping hole can effectively reduce the pressure fluctuation of the oil, reduce the impact of the oil on the pressure limiting valve, and improve the opening stability of the pressure limiting valve.

Description of drawings

Fig. 1 is a structural schematic diagram of a traditional oil pump pressure limiting valve;

Fig. 2 is a structural schematic diagram of an oil pump pressure limiting valve with a damping hole according to the present invention;

Fig. 3 is an enlarged view of part A in Fig. 2 .

The reference signs are:

1——Spring 2——Plunger 3——Feedback oil port

4——Oil drain port 5——Transfer chamber 6——Feedback oil chamber

2a——first cylindrical portion 2b——rod portion 2c——second cylindrical portion

2d——damping hole 2d1——first through hole 2d2——second through hole

2d3 - the third through hole.

Detailed ways

In order to facilitate the understanding of those skilled in the art, the present invention will be further described below in conjunction with the embodiments and accompanying drawings, and the contents mentioned in the embodiments are not intended to limit the present invention.

In describing the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", The orientation or positional relationship indicated by "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device Or elements must have a certain orientation, be constructed and operate in a certain orientation, and thus should not be construed as limiting the invention.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, or it can be two The internal communication of each element may be directly connected or indirectly connected through an intermediary, and those skilled in the art can understand the specific meaning of the terms according to specific situations.

As shown in Figures 2 and 3, an oil pump pressure limiting valve with a damping hole includes a valve hole, a spring 1 and a plunger 2 arranged in the valve hole, and the middle and lower parts of the valve hole wall are respectively provided with The feedback oil port 3 and the oil drain port 4, the plunger 2 includes a first cylindrical part 2a and a rod-shaped part 2b, one end of the spring 1 is connected to the top of the valve hole, and the other end is installed in the first cylindrical part 2a, the rod One end of the rod-shaped part 2b is connected to the bottom end of the first cylindrical part 2a, and a transition chamber 5 is formed between the rod-shaped part 2b and the hole wall of the valve hole. The plunger 2 also includes a The second cylindrical part 2c, a feedback oil chamber 6 is formed between the second cylindrical part 2c and the bottom of the valve hole, and the connection between the second cylindrical part 2c and the rod-shaped part 2b is opened with a communication transfer chamber 5 and The damping hole 2d of the feedback oil chamber 6, when the oil pressure at the oil outlet of the oil pump is too high, the feedback oil at the oil outlet can enter the feedback oil chamber 6 through the feedback oil port 3, the transfer chamber 5 and the damping hole 2d in sequence, Push the plunger 2 to overcome the elastic force of the spring 1 and move upward until the first cylindrical part 2a moves away from the position blocked by the oil drain port 4 , so that the feedback oil port 3 and the oil drain port 4 communicate through the transfer chamber 5 .

Compared with the traditional oil pump pressure limiting valve, the oil pump pressure limiting valve with orifice in this embodiment only adds the second cylindrical part 2c to the plunger 2, and the second cylindrical part 2c The damping hole 2d is opened on the rod-shaped part 2a. The structure of this pressure limiting valve is very simple. Compared with drilling the damping hole 2d inside the pump body, this embodiment can also simplify the structure of the pump body and reduce the difficulty of processing. A feedback oil chamber 6 is formed between the second cylindrical portion 2c of the pressure limiting valve and the hole wall of the valve hole in this embodiment, and the feedback oil chamber 6 passes through the damping hole 2d on the plunger 2 and the transfer chamber 5 Connected, that is, communicated with the feedback oil port 3 and the oil outlet of the oil pump. When the feedback oil at the oil outlet of the oil pump reaches the transfer chamber 5 through the feedback oil port 3, the feedback oil will enter the feedback oil through the damping hole 2d chamber 6, at this time, the plunger 2 will not only receive the pressure of the feedback oil in the transfer chamber 5, but also the pressure of the feedback oil in the feedback oil chamber 6, because the second cylindrical part 2c and the first cylindrical part 2a are respectively Located at both ends of the rod-shaped part 2b, the feedback oil in the transfer chamber 5 exerts pressure on the opposite end surfaces of the first cylindrical part 2a and the second cylindrical part 2c, and the two pressures are in opposite directions and cancel each other out , and the feedback oil in the feedback oil chamber 6 only exerts pressure on the second cylindrical part 2c, and this pressure can push the plunger 2 to overcome the elastic force of the spring 1 and move upward until the pressure limiting valve is opened. It can be seen from this that the pressure limiting valve in this embodiment does not directly drive the plunger 2 to move by the oil at the oil outlet, but pushes the plunger 2 to move through the feedback oil in the feedback oil chamber 6. During this process , when the oil at the oil outlet enters the feedback oil chamber 6 from the transfer chamber 5 through the damping hole 2d, the damping hole 2d can effectively reduce the pressure fluctuation of the oil, reduce the impact of the oil on the pressure limiting valve, and increase the pressure of the pressure limiting valve. Turn on stability.

Further, the first cylindrical part 2a is a cylindrical body with an opening facing upwards, and one end of the spring 1 is installed in the cylindrical body, and the second cylindrical part 2c is a cylindrical body with an opening facing downwards, and the cylindrical body and the valve hole The volume of the feedback oil chamber 6 formed between the hole bottoms changes with the movement of the plunger 2. When the plunger 2 moves upward, the volume of the feedback oil chamber 6 increases, and vice versa.

Specifically, the damping hole 2d includes a first through hole 2d1 transversely penetrating through the rod-shaped portion and a second through hole 2d2 vertically communicating with the first through hole 2d1, the upper end of the second through hole 2d2 communicates with the first through hole 2d1, The lower end communicates with the feedback oil chamber 6, and the diameter of the first through hole 2d1 is larger than the diameter of the second through hole 2d2. However, when the oil pressure at the oil outlet is too high, as shown in Figure 3, the feedback oil at the oil outlet first passes through the feedback oil port 3 to the transfer chamber 5, and then passes through the first through hole 2d1 and the second through hole 2d2 to reach the feedback chamber. The oil chamber 6, during this process, the first through hole 2d1 and the second through hole 2d2 can buffer the impact force of the feedback oil on the plunger 2, and reduce the pressure fluctuation of the oil.

In order to further reduce the pressure fluctuation of the oil, the damping hole 2d also includes a third through hole 2d3 whose diameter gradually increases from top to bottom, the upper end of the third through hole 2d3 communicates with the lower end of the second through hole 2d2, and the third through hole The lower end of 2d3 communicates with the feedback oil chamber 6 .

Furthermore, the joints between the rod-shaped portion 2b and the first cylindrical portion 2a and the second cylindrical portion 2c are inclined plane structures. When the oil at the oil outlet flows into the transfer chamber 5 from the feedback oil port 3, the oil will be buffered on the slope structure, so that the process of oil circulation can be carried out slowly, which can reduce the pressure fluctuation of the oil and also The noise of oil hitting the components here can be reduced.

The above-mentioned embodiments are preferred implementation solutions of the present invention. In addition, the present invention can also be realized in other ways, and any obvious replacements are within the scope of protection of the present invention without departing from the concept of the technical solution.

In order to make it easier for those skilled in the art to understand the improvement of the present invention compared to the prior art, some drawings and descriptions of the present invention have been simplified, and for the sake of clarity, some other elements have been omitted in this application document, Those of ordinary skill in the art should realize that these omitted elements may also constitute the content of the present invention.

Claims (5)

1. An oil pump pressure limiting valve with a damping hole, including a valve hole, a spring (1) and a plunger (2) arranged in the valve hole, the middle and lower parts of the valve hole wall are respectively provided with feedback valves. Oil port (3) and oil drain port (4), the plunger (2) includes a first cylindrical part (2a) and a rod-shaped part (2b), one end of the spring (1) is connected to the top of the valve hole connected, the other end is installed in the first cylindrical part (2a), one end of the rod-shaped part (2b) is connected with the bottom end of the first cylindrical part (2a), and the rod-shaped part (2b) is connected with the valve A transition chamber (5) is formed between the walls of the hole, and it is characterized in that: the plunger (2) also includes a second cylindrical portion (2c) connected to the other end of the rod-shaped portion (2a), the A feedback oil chamber (6) is formed between the second cylindrical part (2c) and the bottom of the valve hole, and a communication relay is opened at the connection between the second cylindrical part (2c) and the rod-shaped part (2b). chamber (5) and the damping hole (2d) of the feedback oil chamber (6), when the oil pressure at the oil outlet of the oil pump is too high, the feedback oil at the oil outlet can pass through the feedback oil port (3), the transfer chamber ( 5) and the damping hole (2d) enter the feedback oil chamber (6), push the plunger (2) to overcome the elastic force of the spring (1) and move upward until the first cylindrical part (2a) is blocked from the oil drain port (4 ) is removed so that the feedback oil port (3) and the drain port (4) communicate through the transfer chamber (5). 2. The oil pump pressure limiting valve with damping hole according to claim 1, characterized in that: the first cylindrical part (2a) is a cylindrical body with an opening facing upwards, and the second cylindrical part ( 2c) is a cylinder with an opening facing downwards. 3. The oil pump pressure limiting valve with a damping hole according to claim 2, characterized in that: the damping hole (2d) includes a first through hole (2d1) transversely penetrating through the rod-shaped part and connecting with the first through hole (2d1) The second through hole (2d2) connected vertically. The upper end of the second through hole (2d2) communicates with the first through hole (2d1), and the lower end communicates with the feedback oil chamber (6). The first through hole The diameter of the hole (2d1) is larger than the diameter of the second through hole (2d2). 4. The oil pump pressure limiting valve with a damping hole according to claim 3, characterized in that: the damping hole (2d) also includes a third through hole (2d3) whose diameter gradually increases from top to bottom, so The upper end of the third through hole (2d3) communicates with the lower end of the second through hole (2d2), and the lower end of the third through hole (2d3) communicates with the feedback oil chamber (6). 5. The oil pump pressure limiting valve with damping hole according to claim 4, characterized in that: the rod-shaped part (2b) is connected to the first cylindrical part (2a) and the second cylindrical part (2c). The joints are inclined plane structures.