Rack meshing structure with helical teeth

Abstract

The utility model relates to a rack meshing structure with helical teeth. The rack meshing structure comprises an axial rack, a radial rack and a positioning shell. The positioning shell is provided with positioning holes which are vertical to each other and can be used for inserting the axial rack and the radial rack; a second plane flush with the tooth bottom is arranged at the front end of the radial rack, and a first plane perpendicular to the second plane is arranged at the root of the rack at the foremost end of the radial rack. A third plane flush with the tooth top is arranged in front of the tooth at the most front end of the axial rack, and a positioning step is arranged on the front portion of the third plane. The axial racks are firstly inserted into the corresponding positioning holes, the radial racks are inserted into the corresponding positioning holes, and when the two racks are just meshed, a set gap is formed between the edges of the radial racks and the positioning steps. When the radial rack is installed, a positioning tool is not needed for positioning, and a ruler is not needed for measuring the size for positioning; racks are convenient to mesh and install, and the error rate is low.

Description

Technical Field

[0001] The utility model relates to a rack meshing structure with helical teeth, belonging to the technical field of mechanical transmission. Background Art

[0002] An axial flow control valve uses a pair of orthogonal 45° helical racks as a transmission mechanism. The actuator drives the radial rack to move up and down, and drives the axial rack to move left and right through the 45° rack pair, thereby driving the valve core fixed on the axial rack to move. The pressure and flow rate downstream are regulated by the valve core covering the throttle holes on the cage sleeve.

[0003] When assembling the two racks, it is necessary to find the correct meshing position. Otherwise, meshing errors may occur during the installation process, resulting in the radial rack being positioned too high or too low. The existing solution is to first position the axial rack through assembly positioning, and then use a positioning tool or a ruler to find the correct meshing position, which is very inconvenient and inefficient. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a rack meshing structure with helical teeth. When installing this structure, no positioning tool is required, no ruler is needed to find the positioning dimensions, and the installation is reliable, convenient and fast.

[0005] The utility model adopts the following technical solutions:

[0006] A rack meshing structure with helical teeth includes an axial rack 2, a radial rack 1, and a positioning housing; the positioning housing has mutually perpendicular positioning holes for the axial rack 2 and the radial rack 1 to be inserted; the front end of the radial rack 1 has a plane two 102 flush with the tooth bottom, and the frontmost rack root of the radial rack 1 has a plane one 101 perpendicular to the plane two 102; in front of the frontmost tooth of the axial rack 2, there is a plane three 201 flush with the tooth top, and a positioning step 202 is provided at the front part of the plane three 201; the axial rack 2 is first inserted into the corresponding positioning hole, and then the radial rack 1 is inserted into the corresponding positioning hole. When the teeth of the two racks are just meshed, the edge of the radial rack is at a set gap from the positioning step 202.

[0007] Preferably, the set gap is 2 mm.

[0008] Preferably, the positioning housing is the valve body of the axial flow control valve.

[0009] Further, an axial bushing 3 for limiting the axial rack is also installed in the valve body.

[0010] Furthermore, a valve core 4 is provided in the valve body, and the valve core 4 is fixedly connected to the front end of the axial rack 2.

[0011] Furthermore, the valve core 4 and the cage 5 can slide relative to each other. By covering the holes of the cage 5 with the valve core 4, the valve opening is adjusted.

[0012] The installation method of the above-mentioned rack meshing structure with helical teeth includes the following steps: Insert the axial rack 2 into the axial bushing 3, and then insert the radial rack 1 so that the plane two 102 cooperates with the plane three 201; in this way, the axial rack 2 can only move left and right, and the radial rack 1 can only move up and down without rotation; Pull out the axial rack 2 so that the positioning step 202 contacts the radial rack 1, press the radial rack 1 down so that the plane one 101 contacts the axial rack 2, firmly hold the radial rack 1, and slowly push the axial rack 2 inward. When the axial rack reaches the meshing position, due to continuously pressing the radial rack 1, under the action of force, the teeth of the two racks collide and then start to mesh; continue to push the axial rack 2 inward, and the radial rack 1 will move down accordingly, thus completing effective meshing.

[0013] The beneficial effects of the present utility model are as follows: When installing the radial rack, there is no need for a positioning tooling for positioning, nor is it necessary to measure the dimensions with a ruler; the rack meshing installation is convenient and the error rate is low. Description of the Drawings

[0014] Figure 1 It is a schematic diagram of the working principle of an axial flow regulating valve.

[0015] Figure 2 It is a schematic diagram of the radial rack in the present utility model. Among them, (a) is the front view of the surface where the helical teeth of the radial rack are located, and (b) is the right view of (a).

[0016] Figure 3 It is a schematic diagram of the axial rack in the present utility model. Among them, (a) is the front view of the surface where the helical rack of the axial rack is located, and (b) is the top view of (a).

[0017] Figure 4 It is a schematic diagram of the rack installation in the present utility model. Among them, (a) is the main view sectional view of the installation, and (b) is the right view sectional view of the installation.

[0018] Figure 5 It is a schematic diagram when the two racks just mesh in the present utility model.

[0019] Figure 6 It is a three-dimensional schematic diagram of the rack meshing structure with helical teeth of the present utility model.

[0020] In the figure, 1. Radial rack, 2. Axial rack, 3. Axial bushing, 4. Valve core, 5. Cage, 101. Plane one, 102. Plane two, 201. Plane three, 202. Positioning step. Detailed Embodiments

[0021] The present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0022] Figure 1 The working principle diagram of the axial flow regulating valve is shown. For the rack and pinion meshing structure with helical teeth in this embodiment applied to the axial flow regulating valve,

[0023] See Figure 1 , a rack and pinion meshing structure with helical teeth, includes an axial rack 2, a radial rack 1, and a positioning housing; the positioning housing has perpendicular positioning holes for the axial rack 2 and the radial rack 1 to be inserted into.

[0024] Combined with Figure 2 , the front end of the radial rack 1 has a plane two 102 flush with the tooth bottom, and the root of the rack at the very front of the radial rack 1 has a plane one 101 perpendicular to the plane two 102;

[0025] Combined with Figure 3 again, in front of the frontmost tooth of the axial rack 2, there is a plane three 201 flush with the tooth top, and a positioning step 202 is provided at the front part of the plane three 201.

[0026] It can be understood that the axial rack 2 is first inserted into the corresponding positioning hole, and then the radial rack 1 is inserted into the corresponding positioning hole. When the teeth of the two racks just mesh, the edge of the radial rack has a set gap from the positioning step 202, as Figure 5 shown.

[0027] In this embodiment, the set gap is preferably 2 mm.

[0028] In this embodiment, the positioning housing is the valve body of the axial flow regulating valve.

[0029] See Figure 1 , an axial bushing 3 for limiting the axial rack is also installed in the valve body.

[0030] See Figure 1 , a valve core 4 is provided in the valve body, and the valve core 4 is fixedly connected to the front end of the axial rack 2.

[0031] Continue to see Figure 1 , the valve core 4 can also slide relative to the cage 5, and the opening degree of the valve is adjusted by the valve core 4 covering the holes of the cage 5.

[0032] During installation, insert the axial rack 2 into the axial bushing 3, and then insert the radial rack 1 so that the plane II 102 mates with the plane III 201. In this way, the axial rack 2 can only move left and right, and the radial rack 1 can only move up and down without rotation. Pull out the axial rack 2 so that the positioning step 202 contacts the radial rack 1, press down the radial rack 1 so that the plane I 101 contacts the axial rack 2, and firmly hold the radial rack 1. Slowly push the axial rack 2 inward. When the axial rack reaches the meshing position, due to continuously pressing the radial rack 1, the two racks will collide under the action of force, and a "pop" sound can be heard. The teeth of the two racks start to mesh. Continue to push the axial rack inward, and the radial rack will move downward accordingly, thus completing effective meshing.

[0033] When installing the radial rack of the present utility model, there is no need for a positioning tooling for positioning, nor is it necessary to measure dimensions with a ruler; the meshing installation of the racks is convenient and the error rate is low.

[0034] The above are the preferred embodiments of the present utility model. Those of ordinary skill in the art can also make various transformations and improvements on this basis. Without departing from the general concept of the present utility model, these transformations or improvements fall within the scope of protection required by the present utility model.

Claims

1. A rack meshing structure with helical teeth, characterized in that: It includes an axial rack (2), a radial rack (1), and a positioning housing; The positioning housing has mutually perpendicular positioning holes into which the axial rack (2) and the radial rack (1) can be inserted; The front end of the radial rack (1) has a plane two (102) flush with the tooth bottom, and the root of the rack at the very front end of the radial rack (1) has a plane one (101) perpendicular to the plane two (102); In front of the frontmost tooth of the axial rack (2), there is a plane three (201) flush with the tooth top, and a positioning step (202) is provided at the front part of the plane three (201); The axial rack (2) is first inserted into the corresponding positioning hole, and the radial rack (1) is inserted into the corresponding positioning hole. When the two racks are just meshed, the edge of the radial rack is at a set gap from the positioning step (202).

2. The rack meshing structure with helical teeth according to claim 1, characterized in that: The set gap is 2 mm.

3. The rack meshing structure with helical teeth according to claim 1, characterized in that: The positioning housing is the valve body of an axial flow regulating valve.

4. The rack meshing structure with helical teeth according to claim 3, characterized in that: An axial bushing (3) for limiting the axial rack is also installed in the valve body.

5. The rack meshing structure with helical teeth according to claim 3, characterized in that: A valve core (4) is provided in the valve body, and the valve core (4) is fixedly connected to the front end of the axial rack (2).

6. The rack meshing structure with helical teeth as described in claim 5, characterized in that: The valve core (4) and the cage (5) can move relative to each other, and the valve opening is adjusted by the valve core (4) covering the holes of the cage (5).

7. The installation method of the rack meshing structure with helical teeth according to claim 4, characterized in that: It includes the following steps: Insert the axial rack (2) into the axial bushing (3), and insert the radial rack (1) so that the plane two (102) cooperates with the plane three (201); in this way, the axial rack (2) can only move left and right, and the radial rack (1) can only move up and down without rotation; Pull the axial rack (2) outwards so that the positioning step (202) contacts the radial rack (1), press the radial rack (1) downwards so that the plane one (101) contacts the axial rack (2), firmly hold the radial rack (1), and slowly push the axial rack (2) inwards. When the axial rack reaches the meshing position, due to continuously pressing the radial rack (1), under the action of the force, the teeth of the two racks collide and then start to mesh; continue to push the axial rack (2) inwards, and the radial rack (1) will move downwards accordingly, thus completing effective meshing.

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