EGR valve for gasoline engine

Abstract

The utility model relates to the technical field of EGR valves, and discloses an EGR valve for a gasoline engine, which comprises a valve body, a direct current motor, an intermediate gear and a valve rod, the direct current motor is fixedly arranged on the valve body, the output end of the direct current motor is provided with an output gear, the valve body is provided with a gear shaft, the intermediate gear is rotatably arranged on the gear shaft, and the output gear is meshed with the intermediate gear. A concave involute groove is formed in the end face of the intermediate gear, one end of the valve rod is connected with a connecting arm, a bearing pin is arranged on the connecting arm, a bearing is fixedly arranged on the bearing pin, the bearing is rotationally arranged in the involute groove, a mounting cavity is formed in the valve body, a torsional spring is arranged in the mounting cavity, one end of the torsional spring is fixed in the mounting cavity, and the other end of the torsional spring is fixed in the mounting cavity. And the other end is connected with the intermediate gear. The utility model has the advantages that the clamping stagnation risk of the product is reduced by adopting the torsion spring reset structure; an involute groove is designed in the intermediate gear, transmission stress and a motor gear are meshed on the same plane, meshing of the intermediate gear is improved, and the service life of a product is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of EGR valves, in particular to an EGR valve for a gasoline engine. Background Art

[0002] In the current application of EGR technology, the EGR valve transmission structure often uses a gear transmission mechanism. Generally, the intermediate gear adopts a cam-shaped linear mechanism to convert rotation into linear motion, and the product reset adopts a double spring structure. There is a high requirement for the consistency of the two spring force values, otherwise it is easy to deflect and get stuck; in addition, the motor gear, the intermediate gear and the bearing are not in the same plane, and the meshing surface of the intermediate gear has inconsistent force, which affects the service life. Utility Model Content

[0003] The utility model aims to overcome the shortcomings of the prior art and provide an EGR valve for a gasoline engine.

[0004] The purpose of the utility model is achieved through the following technical solutions: An EGR valve for a gasoline engine, comprising a valve body, a DC motor, an intermediate gear and a valve stem, wherein the DC motor is fixedly arranged on the valve body, an output gear is arranged at the output end of the DC motor, a gear shaft is arranged on the valve body, the intermediate gear is rotatably arranged on the gear shaft, the output gear is meshed with the intermediate gear, an inwardly concave involute groove is arranged on the end surface of the intermediate gear, a connecting arm is connected to one end of the valve stem, a bearing pin is arranged on the connecting arm, a bearing is fixedly arranged on the bearing pin, the bearing is rotatably arranged in the involute groove, an installation cavity is arranged on the valve body, a torsion spring is arranged in the installation cavity, one end of the torsion spring is fixed in the installation cavity, and the other end is connected to the intermediate gear.

[0005] Specifically, an air channel is provided on the valve body, a sliding hole connecting the air channel is provided on the valve body, the valve stem is slidably arranged in the sliding hole, the air channel has an air inlet and an air outlet, a valve seat is provided between the air inlet and the air outlet, one end of the valve stem is connected to a valve core, and the valve core cooperates with the valve stem.

[0006] Specifically, the connecting arm is L-shaped, one end of which is connected to the bearing pin, and the other end of which is connected to the valve stem.

[0007] Specifically, a filter cover is provided at the lower end of the sliding hole, a guide sleeve is provided at the upper end of the sliding hole, a sealing assembly is provided between the guide sleeve and the filter cover, and the valve stem sliding sleeve is provided in the filter cover, the guide sleeve and the sealing assembly.

[0008] Specifically, a limit block is arranged on the other end surface of the intermediate gear, and a stop block is arranged on the valve body on the moving path of the limit block.

[0009] The utility model has the following advantages:

[0010] The utility model adopts a torsion spring reset structure to reduce the risk of gear jamming; an involute groove is designed in the intermediate gear, and the transmission force is meshed with the motor gear on the same plane, which improves the meshing of the intermediate gear and ensures the product life. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the internal structure of the valve body of the utility model;

[0012] Figure 2 This is a schematic diagram of the valve stem arrangement structure of the utility model;

[0013] Figure 3 This is a schematic diagram of the connecting arm structure of the utility model;

[0014] Figure 4 This is a schematic diagram of the overall structure of the EGR valve of the utility model;

[0015] Figure 5 for Figure 4 A schematic diagram of the enlarged structure at A in the middle;

[0016] Figure 6 This is a schematic diagram of the structure of the intermediate gear of the utility model;

[0017] Figure 7 This is a schematic diagram of the torsion spring structure of the utility model;

[0018] In the figure: 1-valve body, 2-DC motor, 3-output gear, 4-intermediate gear, 5-connecting arm, 6-gear shaft, 7-involute groove, 8-bearing, 9-valve stem, 10-guide sleeve, 11-sealing assembly, 12-filter cover, 13-valve core, 14-valve seat, 16-limit block, 17-torsion spring, 18-stopper, 19-airway. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model, that is, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The components of the embodiments of the utility model described and shown in the drawings can be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the utility model provided in the accompanying drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0021] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including a..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0022] The present invention is further described below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following description.

[0023] like Figures 1 to 7As shown, an EGR valve for a gasoline engine comprises a valve body 1, a DC motor 2, an intermediate gear 4 and a valve stem 9, wherein the DC motor 2 is fixedly arranged on the valve body 1, an output gear 3 is arranged at the output end of the DC motor 2, a gear shaft 6 is arranged on the valve body 1, the intermediate gear 4 is rotatably arranged on the gear shaft 6, the output gear 3 is meshed with the intermediate gear 4, an inwardly concave involute groove 7 is arranged on the end surface of the intermediate gear 4, a connecting arm 5 is connected to one end of the valve stem 9, a bearing pin is arranged on the connecting arm 5, a bearing 8 is fixedly arranged on the bearing pin, and the bearing 8 is rotatably arranged in the involute groove 7, an installation cavity is arranged on the valve body 1, a torsion spring 17 is arranged in the installation cavity, one end of the torsion spring 17 is fixed in the installation cavity, and the other end of the torsion spring 17 is connected to the installation cavity. In this embodiment, the DC motor 2 drives the output gear 3 to rotate, and the output gear 3 meshes with the intermediate gear 4. In this way, the DC motor 2 drives the intermediate gear 4 to rotate. An inwardly concave involute groove 7 is provided on the end surface of the intermediate gear 4, and the involute groove 7 is provided along the involute. The bearing 8 is placed in the involute groove 7 and is clearance-matched with the involute groove 7. When the intermediate gear 4 rotates, the bearing 8 rotates in the involute groove 7. Under the action of the involute, the bearing 8 is away from the center of the intermediate gear 4, and the valve stem 9 is pushed to move along the axial direction of the valve stem 9 through the bearing 8, thereby realizing The valve body 1 is provided with an installation cavity, and a torsion spring 17 is provided in the installation cavity. The torsion spring 17 is sleeved on the outside of the gear shaft 6, so that when the intermediate gear 4 rotates, the intermediate gear 4 causes the torsion spring 17 to twist. When the EGR valve is reset and not powered on, the intermediate gear 4 can be driven by the torsion spring 17 to rotate, thereby driving the bearing 8 to rotate in the involute groove 7 to achieve product reset; the torsion spring 17 provides preload and reset force for the transmission system. With such a driving method, the intermediate gear 4 will not be stuck when reset, and it is reliable to use.

[0024] Further, the valve body 1 is provided with an air passage 19, the valve body 1 is provided with a sliding hole connecting the air passage 19, the valve stem 9 is slidably arranged in the sliding hole, the air passage 19 has an air inlet and an air outlet, a valve seat 14 is arranged between the air inlet and the air outlet, one end of the valve stem 9 is connected with a valve core 13, and the valve core 13 cooperates with the valve stem 9. In this embodiment, the valve stem 9 is slidably arranged in the sliding hole to limit the valve stem 9, and when the intermediate gear 4 rotates, the bearing 8 can only push the valve stem 9 to move axially to realize the opening and closing of the valve, and when the valve stem 9 is in the initial position, the valve core 13 is tightly fitted with the valve seat 14, so that the valve is closed, and the air inlet and the air outlet are not connected.

[0025] Further, the connecting arm 5 is L-shaped, one end of which is connected to the bearing pin, and the other end is connected to the valve stem 9. In this embodiment, in order to make the output gear 3, the intermediate gear 4, the bearing 8 and the valve stem 9 in the same plane, the connecting arm 5 is set to an L-shaped structure, the end connected to the bearing pin is parallel to the end face of the intermediate gear 4, and the end connected to the valve stem 9 is perpendicular to the end face of the intermediate gear 4. Such a setting ensures that the meshing surface of the intermediate gear 4 is subjected to consistent force, thereby increasing the service life of the product.

[0026] Furthermore, a filter cover 12 is provided at the lower end of the slide hole, a guide sleeve 10 is sleeved at the upper end of the slide hole, a sealing assembly 11 is provided between the guide sleeve 10 and the filter cover 12, and the valve stem 9 is slidably sleeved in the filter cover 12, the guide sleeve 10 and the sealing assembly 11. The sealing of the gear cavity and the airway is achieved by arranging the sealing assembly 11 in the slide hole.

[0027] Furthermore, a limit block 16 is provided on the other end face of the intermediate gear 4, and a stop block 18 is provided on the valve body 1 on the moving path of the limit block 16. In this embodiment, a stop block 18 is provided on the valve body 1 to limit the limit position of the intermediate gear 4, and the limit block 16 rotates with the intermediate gear 4 when the intermediate gear 4 rotates. When the limit block 16 rotates to the stop block 18, the intermediate gear 4 stops rotating due to the restriction of the stop block 18, thereby limiting the stroke of the valve stem 9.

[0028] A magnet is arranged on the connecting arm 5, and a Hall sensor circuit assembly is arranged on the upper cover of the valve. When the valve stem 9 moves up and down, the magnet moves up and down accordingly, and the Hall chip on the Hall sensor circuit assembly senses the change in the magnetic field and outputs a linear voltage, thereby realizing real-time feedback of the voltage signal of the valve opening.

[0029] The above is only a preferred embodiment of the utility model, and does not limit the utility model in any form. Any technician familiar with the field can make many possible changes and modifications to the technical solution of the utility model by using the above-mentioned technical content without departing from the scope of the technical solution of the utility model, or modify it into an equivalent embodiment of equivalent changes. Therefore, any changes, modifications, equivalent changes and modifications made to the above embodiments based on the technology of the utility model without departing from the content of the technical solution of the utility model shall fall within the protection scope of the technical solution of the utility model.

Claims

1. An EGR valve for a gasoline engine, characterized in that: The valve stem (9) comprises a valve body (1), a DC motor (2), an intermediate gear (4) and a valve rod (9), wherein the DC motor (2) is fixedly arranged on the valve body (1), an output gear (3) is arranged at the output end of the DC motor (2), a gear shaft (6) is arranged on the valve body (1), the intermediate gear (4) is rotatably arranged on the gear shaft (6), the output gear (3) meshes with the intermediate gear (4), an end surface of the intermediate gear (4) is provided with an inwardly concave involute groove (7), one end of the valve stem (9) is connected to a connecting arm (5), a bearing pin is arranged on the connecting arm (5), a bearing (8) is fixedly arranged on the bearing pin, and the bearing (8) is rotatably arranged in the involute groove (7), and an installation cavity is arranged on the valve body (1), a torsion spring (17) is arranged in the installation cavity, one end of the torsion spring (17) is fixed in the installation cavity, and the other end of the torsion spring (17) is connected to the installation cavity.

2. The EGR valve for a gasoline engine according to claim 1, characterized in that: The valve body (1) is provided with an air passage (19), the valve body (1) is provided with a sliding hole connecting the air passage (19), the valve stem (9) is slidably arranged in the sliding hole, the air passage (19) has an air inlet and an air outlet, a valve seat (14) is arranged between the air inlet and the air outlet, one end of the valve stem (9) is connected to a valve core (13), and the valve core (13) cooperates with the valve stem (9).

3. The EGR valve for a gasoline engine according to claim 1, characterized in that: The connecting arm (5) is L-shaped, one end of which is connected to the bearing pin, and the other end of which is connected to the valve stem (9).

4. The EGR valve for a gasoline engine according to claim 2, characterized in that: A filter cover (12) is provided at the lower end of the slide hole, a guide sleeve (10) is sleeved at the upper end of the slide hole, a sealing assembly (11) is provided between the guide sleeve (10) and the filter cover (12), and the valve stem (9) is slidably sleeved within the filter cover (12), the guide sleeve (10) and the sealing assembly (11).

5. The EGR valve for a gasoline engine according to claim 1, characterized in that: A limit block (16) is provided on the other end surface of the intermediate gear (4), and a stop block (18) is provided on the valve body (1) on the moving path of the limit block (16).

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