Pressure relief structure of an oil sump

Abstract

The present application relates to the technical field of engine oil sump, in particular to a pressure relief structure of an oil sump. The oil sump is provided with a pressure relief valve on the exhaust side of the engine. The pressure relief valve comprises a housing, a valve core push rod, a spring and a sealing cover plate. The housing is provided with an air inlet cavity, an exhaust cavity and a valve core assembly cavity located in the middle section and connected with the air inlet cavity and the exhaust cavity. The air inlet cavity is connected with the inside of the oil sump. The valve core push rod is slidably arranged in the valve core assembly cavity. The valve core push rod and the wall surface of the valve core assembly cavity have an airflow gap. The front end of the valve core push rod is provided with a stop head. The spring is sleeved on the valve core push rod and located in the air inlet cavity. One end of the spring is in elastic contact with the stop head. The other end of the valve core push rod is fixedly connected with the sealing cover plate. The sealing cover plate is in sealing contact with the bottom surface of the exhaust cavity. The above structure can automatically exhaust when the in-cylinder pressure is too high, effectively avoiding the damage of the oil sump.

Description

Technical Field

[0001] This invention relates to the field of engine oil pan technology, and more specifically to a pressure relief structure for an oil pan. Background Technology

[0002] Natural gas engines operating in cold regions face the problem of icing during cold starts. When the breather ices, crankcase pressure continuously increases, requiring timely depressurization. The burst pressure requirement for plastic oil pans is greater than 1.5 bar, with actual measurements showing that the oil pan ruptures at approximately 2.7 bar. However, in the case of icing, crankcase pressure rises above this burst pressure limit. Therefore, conventional oil pans have a significant risk of failure under abnormal cold-start conditions in cold regions. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a pressure relief structure for the oil pan, which can automatically relieve pressure when the cylinder pressure of the engine rises abnormally, thus preventing the oil pan from rupturing.

[0004] This invention provides a pressure relief structure for an oil pan, including an oil pan with a pressure relief valve installed on the exhaust side of the engine. The pressure relief valve includes a housing, a valve core push rod, a spring, and a sealing cover. The housing has an axial through hole, which includes an intake chamber and an exhaust chamber located at both ends, and a valve core assembly chamber located in the middle and connecting the intake chamber and the exhaust chamber. The intake chamber communicates with the interior of the oil pan. The valve core push rod is slidably disposed in the valve core assembly chamber, and there is an airflow gap between the valve core push rod and the wall of the valve core assembly chamber. The front end of the valve core push rod has a stop. The spring is sleeved on the valve core push rod and located in the intake chamber. One end of the spring is in elastic contact with the stop, and the other end of the valve core push rod is fixedly connected to the sealing cover. The sealing cover is in sealing contact with the bottom surface of the exhaust chamber.

[0005] Preferably, the housing has an oil baffle plate at one end of the air intake chamber, the oil baffle plate has a through hole communicating with the air intake chamber, and filter paper is provided between the oil baffle plate and the stop of the valve core push rod.

[0006] Preferably, the through hole includes an oil inlet hole and an oil return hole, wherein the diameter of the oil inlet hole is smaller than that of the oil return hole, and the number of oil inlets is greater than that of the oil return holes.

[0007] Preferably, the oil return hole is an arc-shaped hole, and there are two arc-shaped holes. The arc-shaped holes are symmetrically arranged on the outer side of the oil baffle plate, and the oil inlet holes are densely arranged on the inner side of the arc-shaped holes.

[0008] Preferably, the sealing cover plate has a sealing gasket on its inner side.

[0009] More preferably, the end face of the air inlet cavity towards the valve core assembly cavity is provided with a spring assembly cavity, and the spring is compressedly arranged in the spring assembly cavity.

[0010] More preferably, the oil pan is provided with a pressure relief valve mounting seat at the engine exhaust side, the pressure relief valve mounting seat is internally provided with a pressure relief valve mounting cavity, the pressure relief valve is arranged in the pressure relief valve mounting cavity, and the wall surface of the pressure relief valve mounting cavity is interference-fitted.

[0011] More preferably, the outer wall of the shell is protrusively provided with a ring-mounted gear ring axially limitedly matched with the wall surface of the pressure relief valve mounting cavity, and the ring-mounted gear ring is circumferentially provided with a toothed body radially limitedly matched with the wall surface of the pressure relief valve mounting cavity.

[0012] The beneficial effects of the present application are that: after the pressure relief valve is assembled on the oil pan, the gas in the oil pan can act on the valve core push rod through the air inlet cavity, when the pressure in the oil pan reaches a threshold value, the valve core push rod is displaced by overcoming the spring compression force, so as to separate the end face of the sealing cover plate from the bottom surface of the exhaust cavity, the in-cylinder gas is discharged through the air inlet cavity, the airflow gap between the valve core push rod and the wall surface of the valve core assembly cavity and the exhaust cavity, and the pressure relief is realized. When the in-cylinder pressure gradually decreases until the pressure is less than the spring compression force, the valve core push rod is reset under the action of the spring restoring force, and the sealing cover plate continues to close the exhaust cavity. The above structure can realize automatic exhaust when the in-cylinder pressure is too large, and effectively avoid the damage of the oil pan. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 、 2 It is a schematic diagram of the assembly of the pressure relief valve on the oil pan of the present application;

[0014] Figure 3 It is an exploded structure schematic diagram of the pressure relief valve of the present application;

[0015] Figure 4 It is an axial sectional view of the pressure relief valve of the present application;

[0016] Figure 5 It is a side view of the air inlet end of the pressure relief valve of the present application;

[0017] Figure 6 It is a side view of the exhaust end of the pressure relief valve of the present application. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects of the present application more clearly understood, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0019] It should be noted that when an element is referred to as being "fixed" or "set" on another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or indirectly connected to the other element.

[0020] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0021] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0022] As shown in Figure 1 , 2 The pressure relief structure of the oil pan of the present application includes an oil pan 1 and a pressure relief valve 2. The pressure relief valve 2 is installed on the engine exhaust side of the oil pan 1 and is located at the 1 / 2 position of the length of the oil pan. The oil pan 1 is provided with a pressure relief valve mounting seat 3 on the engine exhaust side, and the pressure relief valve mounting seat 3 is internally provided with a pressure relief valve mounting cavity. The pressure relief valve 2 is arranged in the pressure relief valve mounting cavity and is in interference fit with the wall surface of the pressure relief valve mounting cavity.

[0023] Figure 3 , 4 The structure of the pressure relief valve provided by the preferred embodiment of the present application is shown in the structural schematic diagram. For the purpose of illustration, only the parts related to the present embodiment are shown, and the details are as follows:

[0024] The pressure relief valve 2 comprises a housing 4, a valve core push rod 5, a spring 10 and a sealing cover plate 6. The housing 4 is provided with an axial through hole, which comprises an air inlet cavity 12 at two ends, an air outlet cavity 13 and a valve core assembly cavity 14 at the middle section and capable of communicating the air inlet cavity 12 and the air outlet cavity 13. The air inlet cavity 12 is in communication with the inside of the oil pan 1. The valve core push rod 5 is slidingly arranged in the valve core assembly cavity 14, and the valve core push rod 5 and the wall surface of the valve core assembly cavity 14 have an air flow gap 15. The front end of the valve core push rod 5 is provided with a stop head 16. The spring 10 is sleeved on the valve core push rod 5 and located in the air inlet cavity 12. One end of the spring 10 is in elastic contact with the stop head 16. The end surface of the air inlet cavity 12 towards the valve core assembly cavity 14 is provided with a spring assembly cavity 17. The spring 10 is compressedly arranged in the spring assembly cavity 17. The other end of the valve core push rod 5 is fixedly connected with the sealing cover plate 6. The sealing cover plate 6 is in sealing contact with the bottom surface of the air outlet cavity 13. The inner side of the sealing cover plate 6 is provided with a sealing gasket 9. The end surface of the sealing gasket 9 is provided with a protruding rib, which can enhance the sealing. The housing 4 is provided with an oil blocking plate 7 at one end of the air inlet cavity 12. The oil blocking plate 7 is provided with through holes in communication with the air inlet cavity 12. The oil blocking plate 7 and the stop head 16 of the valve core push rod 5 are provided with filter paper 8. The outer wall of the housing 4 is provided with ring-mounted gear rings 11 in axial limiting cooperation with the wall surface of the pressure relief valve mounting cavity. The ring-mounted gear rings 11 are at least three, and the height of the ring-mounted gear rings 11 protruding from the surface of the housing 4 is lower than the height of the hexagonal head at the end of the housing. The ring-mounted gear rings 11 are provided with toothed bodies 20 in radial limiting cooperation with the wall surface of the pressure relief valve mounting cavity.

[0025] As shown in Figure 5 , the through hole comprises an oil inlet hole 18 and an oil return hole 19. The caliber of the oil inlet hole 18 is smaller than that of the oil return hole 19. The number of the oil inlet hole 18 is greater than that of the oil return hole 19. In this embodiment, the oil return hole 19 is an arc-shaped hole. The arc-shaped hole comprises two arc-shaped holes, which are symmetrically arranged on the outer side of the oil blocking plate 7. The oil inlet holes 18 are densely arranged on the inner side of the arc-shaped hole. Among them, the oil inlet hole 18 is used to disperse oil gas to make it fully contact with the filter paper 8, and the oil return hole 19 is used to make the accumulated oil in the air inlet cavity flow back to the oil pan.

[0026] As shown in Figure 6 , the air outlet end of the housing 4 is a hexagonal head shape, which is used to press the pressure relief valve 2 into the oil pan by a wrench. The end surface of the sealing cover plate 6 is provided with an internal hexagonal hole, which is used to threadedly assemble the valve core push rod 5 at the end of the valve core push rod 5 by a hexagonal wrench.

[0027] The working principle of the structure is as follows:

[0028] After the pressure relief valve is assembled on the oil pan, the gas in the oil pan can act on the valve core push rod through the air inlet cavity. When the pressure in the oil pan reaches a threshold value, the valve core push rod is displaced against the spring compression force, causing the end surface of the sealing cover plate to separate from the bottom surface of the exhaust cavity. The gas in the cylinder passes through the air flow gap between the air inlet cavity, the valve core push rod and the valve core assembly cavity wall, and the exhaust cavity to be discharged, thereby achieving pressure relief. When the pressure in the cylinder gradually decreases until the pressure is less than the spring compression force, the valve core push rod is reset under the action of the spring restoring force, and the sealing cover plate continues to close the exhaust cavity.

[0029] The above-described embodiments are only used to illustrate the technical solutions of the present application, but not limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A pressure relief structure of an oil pan, comprising an oil pan (1), characterized by: The oil sump (1) is provided with a pressure relief valve (2) on the engine exhaust side, the pressure relief valve (2) comprises a housing (4), a valve core push rod (5), a spring (10) and a sealing cover plate (6), the housing (4) is provided with an axial through hole, the axial through hole comprises an air inlet chamber (12) and an exhaust chamber (13) at both ends and a valve core assembly chamber (14) in the middle section and can communicate the air inlet chamber (12) and the exhaust chamber (13), the air inlet chamber (12) is communicated with the inside of the oil sump (1), the valve core push rod (5) is slidably arranged in the valve core assembly chamber (14), the valve core push rod (5) and the wall surface of the valve core assembly chamber (14) have an airflow gap (15), the front end of the valve core push rod (5) is provided with a stop head (16), the spring (10) is sleeved on the valve core push rod (5) and located in the air inlet chamber (12), one end of the spring (10) is in elastic contact with the stop head (16), the other end of the valve core push rod (5) is fixedly connected with the sealing cover plate (6), and the sealing cover plate (6) is in sealing contact with the bottom surface of the exhaust chamber (13). The housing (4) is provided with an oil baffle (7) at one end of the air inlet chamber (12), the oil baffle (7) is provided with through holes communicating with the air inlet chamber (12), and the oil baffle (7) and the stop head (16) of the valve core push rod (5) are provided with filter paper (8). The through hole comprises an oil inlet hole (18) and an oil return hole (19), the caliber of the oil inlet hole (18) is smaller than that of the oil return hole (19), and the number of the oil inlet hole (18) is greater than that of the oil return hole (19). The oil return hole (19) is an arc-shaped hole, the arc-shaped hole comprises two, the arc-shaped holes are symmetrically arranged on the outside of the oil baffle (7), and the oil inlet holes (18) are densely arranged on the inside of the arc-shaped hole. The oil sump (1) is provided with a pressure relief valve mounting seat (3) on the engine exhaust side, the pressure relief valve mounting seat (3) is provided with a pressure relief valve mounting cavity inside, the pressure relief valve (2) is arranged in the pressure relief valve mounting cavity and is in interference fit with the wall surface of the pressure relief valve mounting cavity. The outer wall of the housing (4) is provided with an annular gear ring (11) in axial limiting fit with the wall surface of the pressure relief valve mounting cavity, and the annular gear ring (11) is provided with a toothed body (20) in radial limiting fit with the wall surface of the pressure relief valve mounting cavity.

2. The pressure relief structure of an oil pan according to claim 1, characterized by: The inside of the sealing cover plate (6) is provided with a sealing gasket (9).

3. The pressure relief structure of an oil pan according to claim 1, characterized by: The end face of the air inlet chamber (12) towards the valve core assembly chamber (14) is provided with a spring assembly chamber (17), and the spring (10) is arranged in compression in the spring assembly chamber (17).

Images