Middle VVT (Variable Valve Timing) electromagnetic valve with friction reduction structure

Abstract

The utility model discloses a centrally-mounted VVT electromagnetic valve with a friction reduction structure, relates to the technical field of VVT electromagnetic valves, and is mainly used for solving the problems that a magnetism isolating sleeve and an armature of an existing centrally-mounted VVT electromagnetic valve are in sliding friction fit, and the surface contact part of the magnetism isolating sleeve and the armature is seriously abraded. According to the main structure, the electromagnetic coil comprises a front yoke, a coil assembly and a rear end cover which are coaxially connected in sequence, a magnetic isolation sleeve is installed in an inner cavity of the coil assembly, an armature is installed in the magnetic isolation sleeve in a sliding mode, and a plurality of steel balls which are arranged around the armature and can roll in the sliding direction of the armature are arranged between the armature and the magnetic isolation sleeve. According to the centrally-mounted VVT electromagnetic valve with the friction reduction structure, the friction force between the magnetism isolating sleeve and the armature is greatly reduced, the armature moves more smoothly, and meanwhile abrasion of the outer wall of the armature and the inner wall of the magnetism isolating sleeve can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of VVT solenoid valves, in particular to a centrally mounted VVT solenoid valve with a friction reducing structure. Background Art

[0002] The VVT ​​solenoid valve is an important component in the variable valve timing system of the automobile engine. Its function is to regulate and prevent the engine lubrication system from over-pressure. The existing VVT solenoid valves include two types: the center-mounted VVT solenoid valve and the side-mounted VVT solenoid valve. Among them, the center-mounted VVT solenoid valve is more advanced than the side-mounted VVT solenoid valve - the former consumes about 1 / 2 of the oil during operation, which reduces the load on the oil pump. At the same time, the oil consumption is reduced by about 1%, and the corresponding fuel consumption and emissions will also be improved. In addition, the center-mounted VVT solenoid valve can simplify the engine oil channel and improve the response speed. Therefore, engines with higher emission standards are now equipped with center-mounted VVT solenoid valves.

[0003] The central VVT solenoid valve includes a coaxially arranged armature assembly and a front yoke assembly, wherein the armature assembly is composed of a coaxially arranged push rod and an armature, and the front yoke assembly is composed of a front yoke and a guide sleeve pressed at its axis, and the push rod is inserted into the guide sleeve and the two slide and frictionally cooperate. At the same time, a magnetic isolation sleeve is also sleeved on the outside of the armature assembly, and the magnetic isolation sleeve and the armature slide and frictionally cooperate. In addition, a coil assembly that can make the front yoke iron magnetized is also provided outside the magnetic isolation sleeve. During operation, after the coil of the coil assembly is energized, it can drive the armature assembly through the front yoke, so that the push rod in the armature assembly moves axially in the guide sleeve on the front yoke.

[0004] However, due to the sliding friction fit between the magnetic isolation sleeve and the armature, the contact surface is large and the friction resistance is large during operation. Therefore, after a period of operation, the surface contact parts of the magnetic isolation sleeve and the armature will be severely worn, causing the armature assembly to shift inside the magnetic isolation sleeve and generate great resistance, which in turn causes the outer circular end of the armature to be scratched inside the magnetic isolation sleeve, and even damage the mid-mounted VVT solenoid valve. Utility Model Content

[0005] The utility model aims to provide a mid-mounted VVT solenoid valve with a friction reduction structure, which greatly reduces the friction between the magnetic isolation sleeve and the armature, making the armature move more smoothly while reducing the wear of the outer wall of the armature and the inner wall of the magnetic isolation sleeve.

[0006] The utility model provides a technical solution to the above-mentioned technical problems: a mid-mounted VVT solenoid valve with a friction-reducing structure, comprising a front yoke, a coil assembly and a rear end cover coaxially connected in sequence, a magnetic isolation sleeve installed in the inner cavity of the coil assembly, an armature slidably installed in the magnetic isolation sleeve, and a plurality of steel balls arranged around the armature and capable of rolling along the sliding direction of the armature are provided between the armature and the magnetic isolation sleeve.

[0007] As a further improvement of the utility model, a push rod coaxial with the front yoke and slidingly passing through the front yoke is provided on the end surface of the armature close to the front yoke, and a push rod channel for the push rod to pass through is provided at the axis of the front yoke.

[0008] As a further improvement of the present invention, the front yoke is further provided with a plurality of oil guide channels extending in the same direction as the push rod channel and penetrating the front yoke.

[0009] As a further improvement of the present invention, there are three oil guide channels, and the three oil guide channels are rotationally symmetrically arranged around the push rod channel.

[0010] As a further improvement of the present invention, the outer wall of the armature is provided with a plurality of guide grooves extending along the sliding direction thereof, the steel balls correspond to the guide grooves one by one and the steel balls are rollingly installed in the guide grooves.

[0011] As a further improvement of the present invention, the guide groove extends to the armature end surface at one end close to the rear end cover, and a closing structure is provided on the end of the guide groove extending to the armature end surface.

[0012] As a further improvement of the present invention, there are five steel balls, and the five steel balls are rotationally symmetrically arranged around the axis of the armature.

[0013] As a further improvement of the present invention, the coil assembly comprises an electromagnetic coil arranged around the magnetic isolation sleeve, and a mounting seat for positioning and mounting the magnetic isolation sleeve is provided in the inner cavity of the electromagnetic coil.

[0014] As a further improvement of the present invention, the coil assembly further includes a shell sleeved on the outside of the electromagnetic coil.

[0015] As a further improvement of the utility model, the electromagnetic coil and the front yoke are both arranged in the housing. Beneficial Effects

[0016] Compared with the prior art, the advantages of the centrally mounted VVT solenoid valve with a friction reducing structure of the utility model are:

[0017] 1. In the center-mounted VVT solenoid valve, multiple steel balls are arranged around the armature between the armature and the magnetic isolation sleeve. When the coil assembly is energized, the front yoke can generate magnetic attraction to move the armature toward it. During the movement of the armature, the presence of the steel balls can convert the sliding friction between the magnetic isolation sleeve and the armature into rolling friction. Therefore, the center-mounted VVT solenoid valve of this structure can greatly reduce the friction between the magnetic isolation sleeve and the armature while increasing the output effective thrust, thereby making the armature move more smoothly and reducing the wear of the outer wall of the armature and the inner wall of the magnetic isolation sleeve, thereby maintaining the coaxiality of the armature and the magnetic isolation sleeve.

[0018] The present invention will become more clear through the following description in conjunction with the accompanying drawings, which are used to explain the embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is an exploded view of the utility model;

[0021] Figure 2 It is a cross-sectional view of the utility model.

[0022] Among them: 1-front yoke iron; 11-rod channel; 12-oil guide channel; 2-coil assembly; 21-electromagnetic coil; 22-housing; 3-rear end cover; 4-magnetic isolation sleeve; 5-armature; 51-guide groove; 6-rod; 7-steel ball. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; of course, it can also be a mechanical connection or an electrical connection; in addition, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] Embodiments of the present invention will now be described with reference to the accompanying drawings. Example

[0026] The specific implementation of the utility model is as follows Figure 1-2 As shown, a mid-mounted VVT solenoid valve with a friction reduction structure includes a front yoke 1, a coil assembly 2 and a rear end cover 3 which are coaxially connected in sequence. A magnetic isolation sleeve 4 is installed in the inner cavity of the coil assembly 2, and an armature 5 is slidably installed in the magnetic isolation sleeve 4. Among them, a plurality of steel balls 7 are arranged around the armature 5 and can roll along the sliding direction of the armature 5 between the armature 5 and the magnetic isolation sleeve 4. In this embodiment, since the outer circle of the armature 5 is not the main friction surface and its outer circle size needs to be reduced, the armature 5 does not need to require excessive roughness accuracy and dimensional accuracy, and can be formed by powder metallurgy, which has the advantage of low production cost.

[0027] When in use, the coil assembly 2 is energized to generate magnetic force on the front yoke 1, and the armature 5 moves toward the side of the front yoke 1 under the magnetic attraction of the front yoke 1. In the process of the movement of the armature 5, the presence of the steel ball 7 can convert the sliding friction between the magnetic isolation sleeve 4 and the armature 5 into rolling friction, and the rolling friction force is about 1 / 10 of the sliding friction force. Therefore, the center-mounted VVT solenoid valve of this structure can greatly reduce the friction between the magnetic isolation sleeve 4 and the armature 5 while increasing the output effective thrust, thereby making the armature 5 move more smoothly and reducing the wear of the outer wall of the armature 5 and the inner wall of the magnetic isolation sleeve 4, thereby maintaining the coaxiality of the armature 5 and the magnetic isolation sleeve 4. Therefore, the center-mounted VVT solenoid valve of this structure can prevent the outer cylindrical end of the armature 5 from being scratched or even damaged inside the magnetic isolation sleeve 4, and can effectively protect the state of components and improve the quality of engine operation.

[0028] The center-mounted VVT solenoid valve can only be provided with a push rod 6 coaxial with the front yoke 1 and slidingly passing through the front yoke 1 on the end face of the armature 5 close to the front yoke 1, and a push rod channel 11 for the push rod 6 to pass through is provided at the axis of the front yoke 1. In this embodiment, the surface of the front yoke 1 is nitrided, and the guide sleeve is replaced by improving the surface hardness and wear resistance of its push rod channel 11. The front yoke 1 before improvement is pressed with the guide sleeve, and the guide sleeve has high requirements for accuracy and roughness, and sliding friction is formed between the push rod 6 and the guide sleeve. The push rod channel 11 of the improved front yoke 1 is consistent with the inner hole size of the guide sleeve, and nitriding treatment is used to improve the hardness and wear resistance.

[0029] In this embodiment, the front yoke 1 is also provided with a plurality of oil guide channels 12 extending in the same direction as the push rod channel 11 and penetrating the front yoke 1. The oil guide channels 12 can play the role of oil flow and air removal when the armature 5 moves. Specifically, there are three oil guide channels 12, and the three oil guide channels 12 are rotationally symmetrically arranged around the push rod channel 11.

[0030] At the same time, in order to install the steel ball 7, a plurality of guide grooves 51 extending along the sliding direction thereof are provided on the outer wall of the armature 5. The steel ball 7 corresponds to the guide groove 51 one by one and the steel ball 7 is installed in the guide groove 51 in a rolling manner. Specifically, the guide groove 51 extends to the end face of the armature 5 near one end of the rear end cover 3. In order to prevent the steel ball 7 from falling off from the end of the guide groove 51 extending to the end face of the armature 5 during the sliding process of the armature 5, a closing structure is also provided on the end of the guide groove 51 extending to the end face of the armature 5. In this embodiment, in order to further ensure that the steel ball 7 does not fall off, a rivet can also be provided at the closing structure to intercept the steel ball 7. In addition, there are five steel balls 7, and the five steel balls 7 are rotationally symmetrically arranged around the axis of the armature 5. After assembling five high-precision steel balls 7, the contact surface changes from the previous outer circle contact to the point contact formed by the five steel balls 7.

[0031] Regarding the coil assembly 2, the coil assembly 2 includes an electromagnetic coil 21 arranged around the magnetic isolation sleeve 4, and a mounting seat for positioning and installing the magnetic isolation sleeve 4 is provided in the inner cavity of the electromagnetic coil 21. Through the mounting seat, the magnetic isolation sleeve 5 can be positioned and installed quickly and accurately. At the same time, the coil assembly 2 also includes a shell 22 sleeved on the outside of the electromagnetic coil 21. In this embodiment, the electromagnetic coil 21 and the front yoke 1 are both arranged in the shell 22.

[0032] The present invention is described above in conjunction with the best embodiments, but the present invention is not limited to the embodiments disclosed above, but should cover various modifications and equivalent combinations based on the essence of the present invention.

Claims

1. A mid-mounted VVT solenoid valve with a friction reduction structure, comprising a front yoke (1), a coil assembly (2) and a rear end cover (3) which are coaxially connected in sequence, a magnetic isolation sleeve (4) being installed in the inner cavity of the coil assembly (2), an armature (5) being slidably installed in the magnetic isolation sleeve (4), characterized in that: A plurality of steel balls (7) are arranged between the armature (5) and the magnetic isolation sleeve (4), and are arranged around the armature (5) and are capable of rolling along the sliding direction of the armature (5).

2. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 1, characterized in that: A push rod (6) is provided on the end surface of the armature (5) on one side close to the front yoke (1), and is coaxial with the front yoke (1) and slides through the front yoke (1). A push rod channel (11) is provided at the axis of the front yoke (1) for the push rod (6) to pass through.

3. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 2, characterized in that: The front yoke iron (1) is also provided with a plurality of oil guide channels (12) extending in the same direction as the push rod channel (11) and penetrating the front yoke iron (1).

4. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 3, characterized in that: There are three oil guide channels (12), and the three oil guide channels (12) are rotationally symmetrically arranged around the push rod channel (11).

5. The mid-mounted VVT solenoid valve with a friction reduction structure according to any one of claims 1 to 4, characterized in that: The outer wall of the armature (5) is provided with a plurality of guide grooves (51) extending along the sliding direction thereof, the steel balls (7) correspond to the guide grooves (51) one by one, and the steel balls (7) are rollingly mounted in the guide grooves (51).

6. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 5, characterized in that: The guide groove (51) extends to the end surface of the armature (5) at one end close to the rear end cover (3), and a closing structure is provided on the end of the guide groove (51) extending to the end surface of the armature (5).

7. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 6, characterized in that: There are five steel balls (7), and the five steel balls (7) are rotationally symmetrically arranged around the axis of the armature (5).

8. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 1, characterized in that: The coil assembly (2) comprises an electromagnetic coil (21) arranged around a magnetic isolation sleeve (4); a mounting seat for positioning and mounting the magnetic isolation sleeve (4) is provided in the inner cavity of the electromagnetic coil (21).

9. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 8, characterized in that: The coil assembly (2) further comprises a housing (22) sleeved on the outside of the electromagnetic coil (21).

10. The mid-mounted VVT solenoid valve with a friction reduction structure according to claim 9, characterized in that: The electromagnetic coil (21) and the front yoke (1) are both arranged in a housing (22).

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