A mechanism for limiting the angle of rotational movement

Abstract

The application provides a mechanism for limiting the angle of rotary motion, belonging to the field of mechanical structure, and particularly suitable for limiting the rotation angle of a main shaft in a ZD6 switch machine structure. The mechanism comprises a ring-shaped part and an oblong part, each having a first inner hole and a second inner hole. The ring-shaped part and the oblong part are attached to each other, and the first inner hole and the second inner hole are coaxial. The first inner hole is a spline structure and is matched with the spline of the main shaft. The minimum inner diameter of the second inner hole is greater than the outer diameter of the spline structure. The end faces of the ring-shaped part and the oblong part, which are attached to each other, respectively have a boss and a groove accommodating the boss, which are matched with each other. The face of the groove away from the center is a circular arc face, and the center of the circular arc face coincides with the center of the spline structure. The groove and the boss are nested and matched by using a spline. The mechanism converts the collision between the stop bolt and the stop pile into the collision between the small end of the oblong part and the stop pile, and then the spline structure of the oblong part and the ring-shaped part collides, the stress section is enlarged, the strength of the part is improved, and the impact life of the part is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of mechanical structures, and in particular to a mechanism for limiting the angle of rotational motion. Background Art

[0002] The ZD6 type switch machine is the most widely used turnout switching equipment in my country's railway transportation. It is widely used on national railway conventional lines, urban rail transit, and industrial and mining enterprise transportation routes. Its proper operation has a significant impact on the transportation efficiency and even transportation safety of the line.

[0003] The ZD6 switch machine drives the rack block to move by rotating the locking gear, which in turn causes the operating rod to extend and retract to switch the turnout. After the locking gear rotates to the final position, the locking arc and the rack block locking arc fit together, achieving mechanical locking and locking the turnout point rail. Among them, the locking gear and the stop bolt are both connected to the main shaft through splines, and the three move together, such as Figure 1 As shown. Since the moving parts still have residual kinetic energy after the motor is powered off, if the main shaft stops beyond the designed angle, it may cause the connected indicating contacts to be disconnected again. Therefore, the ZD6 switch machine is designed with a stop pile 8 and a stop bolt 7 to limit the main shaft stop angle. Figure 2 shown.

[0004] During use, each movement of the ZD6 switch machine will cause a collision between the stop bolt and the stop pile to consume the remaining energy. Due to structural limitations, the connection section between the collision position of the stop bolt 7 and the body is relatively small, which is prone to fatigue. Figure 3 As shown, there have been many cases of unindicated failures caused by the breakage of the stop bolt 7 which has been in service for a long time, which has affected the order of vehicle operation and caused certain economic losses. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention proposes a mechanism for limiting the angle of rotational movement, which converts the collision between the stop bolt and the stop pile into a collision between the small end of the elongated part and the stop pile. The elongated part and the annular part move relative to each other, causing friction or deformation of the spring, and then the tooth structures of the elongated part and the annular part collide. In this process, energy is consumed by the friction of the parts or the deformation of the spring, which reduces the energy of the collision of the tooth structure. In addition, the force-bearing cross-section and the collision cross-section of the tooth structure are increased relative to the original stop bolt and stop pile structure, thereby reducing the stress level of the collision process and extending the impact life of the parts without changing the material properties.

[0006] The present invention provides the following technical solutions:

[0007] A mechanism for limiting the angle of rotational movement comprises an annular part and an elongated part, each having a first inner hole and a second inner hole;

[0008] The annular part and the elongated part fit together; the annular part has a first inner hole, which is a spline structure and fits with the main shaft spline; the elongated part has a second inner hole, the minimum inner diameter of which is larger than the outer diameter of the spline structure; the first inner hole and the second inner hole are coaxial;

[0009] The end surfaces of the annular part and the elongated part that fit together have mutually matching bosses and grooves for accommodating the bosses; the surfaces of the bosses and the grooves away from the center of the circle are arc surfaces;

[0010] The groove and the boss form a tooth-embedded structure for nested cooperation; the two can rotate relative to each other and the rear end surfaces contact and stop each other.

[0011] Preferably, there is friction material between the contact surfaces of the annular part and the elongated part, and when the annular part and the elongated part rotate relative to each other, the elongated part will be subjected to friction.

[0012] Preferably, the friction material is an elastic material.

[0013] Preferably, an elastic element is provided between the contact surfaces of the annular component and the elongated component.

[0014] Preferably, the elastic element is a torsion spring.

[0015] Preferably, the central angle corresponding to the groove profile is greater than the central angle corresponding to the boss profile.

[0016] Preferably, the groove is located on the end face of the elongated part, and the boss is located on the end face of the annular part; or, the groove is located on the end face of the annular part, and the boss is located on the end face of the elongated part.

[0017] Beneficial effects of the present invention:

[0018] The present invention proposes a mechanism for limiting the angle of rotational movement. By adjusting the relative rotation angle change between the annular part and the elongated part, it can adapt to a larger range of rotation angle restrictions; through the friction effect during the relative rotation process of the annular part and the elongated part, the energy in the process of the boss and the groove colliding with the stopper can be reduced, thereby extending the impact life of the parts; according to the energy and stress of the impact process, the boss connection section and the groove remaining section that meet the requirements can be designed, the design restrictions are relatively small, and the design can be flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the ZD6 spindle structure diagram;

[0020] Figure 2 This is a schematic diagram of the cooperation between the stop bolt and the stop pile in the prior art;

[0021] Figure 3It is a schematic diagram of the stop bolt structure in the prior art;

[0022] Figure 4 This is a schematic diagram of the structure of the annular part in Example 1;

[0023] Figure 5 This is a schematic diagram of the structure of the elongated part in Example 1;

[0024] Figure 6 This is a schematic diagram of the nested fit of the annular part and the elongated part in Example 1;

[0025] Figure 7 This is a schematic diagram of the assembly of the annular part and the elongated part in Example 1;

[0026] Figure 8 This is a schematic diagram of the assembly of the annular part and the elongated part in Example 2;

[0027] Figure 9 This is a schematic diagram of the assembly of the annular part and the elongated part in Example 3;

[0028] In the figure, 1, annular part; 2, flat and long part; 3, first inner hole; 4, second inner hole; 5, boss; 6, groove; 7, stop bolt; 8, stop pile. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0031] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of such features; in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0032] Example 1

[0033] Each time the ZD6 switch machine moves, the stop bolt and the stop pile will collide to consume the remaining energy. Due to structural limitations, the connection section between the collision position of the stop bolt and the body is relatively small, making it prone to fatigue fracture due to multiple impacts.

[0034] To this end, this embodiment proposes a mechanism for limiting the rotation angle, replacing the stop pin with the structure of the present invention. When limiting rotation, the small end of the elongated part 2 collides with the stop pin and the tooth structure of the elongated part 2 collides with the annular part 1, ultimately stopping the spindle at the set position. Specifically, Figure 4-Figure 6 As shown, Figure 4 The end face of the annular part 1 has a boss 5. Figure 5 The elongated part 2 has a groove 6. Figure 6 The two are nested to form a tooth-embedded structure. Figure 7 The figure shows an assembly schematic structure. Specifically, it includes a ring part 1 and an elongated part 2, each having a first inner hole 3 and a second inner hole 4. The inner hole of the ring part 1 is a spline structure that mates with the main shaft spline. The end face of the ring part 1 that mates with the elongated part 2 has a boss 5. The inner hole of the elongated part 2 is larger than the outer diameter of the main shaft spline. The elongated part 2 has a groove 6 that accommodates the boss 5. The groove 6 is connected to the inner hole. The outer wall of the groove 6 is an arc surface with the center of rotation as the circle center. The two ends of the boss 5 respectively form a stop surface with the two ends of the groove 6. The two form a nested matching structure with a certain relative rotation angle. In other words, the two can rotate relative to each other for a limited angle until the edges of the boss 5 and the groove 6 come into contact, preventing them from continuing to rotate relative to each other in the same direction. However, they can rotate relative to each other in the opposite direction. After rotating relative to each other in the opposite direction until the other edge of the boss 5 and the groove 6 come into contact, the two can no longer rotate relative to each other in the same direction.

[0035] The boss 5 in this embodiment is an arc-shaped boss 5, the outer wall of which is an arc surface, and the inner wall of which is an extension surface of the spline. The boss 5 structure can also be a cylindrical, square column or other structure.

[0036] The improved structure of this embodiment is that the small end of the flat part 2 collides with the stop post, and then the flat part 2 collides with the tooth structure of the annular part 1, and finally the main shaft stops at the set position. The end of the flat part 2 collides with the stop bolt as a whole, and there is no dangerous section. By selecting an appropriate size, its cross section can be equivalent to that of the stop post, achieving equal strength for both. After the boss 5 collides with the wall of the groove 6, the annular part 1 and the flat part 2 are both subjected to shear force. Since the shear surface is significantly larger than the original shear surface of the stop bolt, when the same material is used, the number of impacts and collisions it withstands increases, and its ability to withstand static loads also increases, that is, the impact fatigue life increases.

[0037] In another embodiment, the groove 6 is located on the end face of the annular part 1, and the boss 5 is located on the end face of the elongated part 2, that is, the positions of the boss 5 and the groove 6 can be interchanged, and the two can also form a tooth-embedded structure for replacing the stop bolt.

[0038] Example 2

[0039] Special, such as Figure 8 As shown, the groove 6 of the elongated part 2 of the present invention is provided on the outer wall, and both ends of the groove 6 are stop surfaces. The arcuate inner wall of the boss 5 of the annular part 1 slides with the wall of the groove 6 to form a tooth-embedded structure.

[0040] Example 3

[0041] Particularly, the boss 5 of the annular part 1 of the present invention is a cylindrical boss 5, or a prismatic boss 5, such as Figure 9 As shown, Figure 9 The cylindrical boss 5 and the groove 6 form a tooth-embedded structural relationship, and the contact surface between the two is an arc surface, which does not cause interference during rotation.

[0042] Example 4

[0043] In this embodiment, friction material is added between the two parts to dissipate kinetic energy through friction. Furthermore, two torsion springs with opposite rotations can be placed between the two parts, or a single torsion spring can be composed of two parts with different rotations. This torsion spring structure restricts relative motion between the two parts in both directions, maintaining a neutral position when not subject to external forces, ensuring that the edges of the boss 5 and the groove 6 do not contact each other.

[0044] In this embodiment, the mechanism separates the stopper into an annular component 1 and an elongated component 2. Rotational restriction is achieved through the collision of the small end of the elongated component 2 with the stopper, and the collision of the tooth structure of the elongated component 2 with the annular component 1, ultimately stopping the spindle at a set position. The entire end of the elongated component 2 collides with the stopper, eliminating any hazardous cross-section. By appropriately sizing the elongated component 2, its cross-section can be made equivalent to that of the stopper, achieving equal strength.

[0045] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A mechanism for limiting the angle of rotational motion, characterized in that: It comprises a ring-shaped part (1) and a flat and long part (2); The annular part (1) and the elongated part (2) are fitted together; the annular part (1) has a first inner hole (3), the first inner hole (3) is a spline structure, and is matched with the main shaft spline; the elongated part (2) has a second inner hole (4), the minimum inner diameter of the second inner hole (4) is larger than the outer diameter of the spline structure; the first inner hole (3) and the second inner hole (4) are coaxial; The end surfaces of the annular part (1) and the elongated part (2) that fit together have mutually fitting bosses (5) and grooves (6) for accommodating the bosses (5); the surface of the groove (6) away from the center is an arc surface, and the center of the arc surface coincides with the center of the spline structure; The groove (6) and the boss (5) form a tooth-embedded structure for nested cooperation; the two can rotate relative to each other and the rear end surfaces contact and stop each other.

2. The mechanism for limiting the rotational motion angle according to claim 1, characterized in that: There is friction material between the contact surfaces of the annular part (1) and the elongated part (2). When the annular part (1) and the elongated part (2) rotate relative to each other, the elongated part (2) is subjected to friction.

3. The mechanism for limiting the rotation angle according to claim 2, characterized in that: The friction material is an elastic material.

4. The mechanism for limiting the rotational motion angle according to claim 1, characterized in that: An elastic element is provided between the fitting surfaces of the annular part (1) and the elongated part (2).

5. The mechanism for limiting the rotational angle according to claim 4, characterized in that: The elastic element is a torsion spring.

6. The mechanism for limiting the rotational angle according to claim 1, characterized in that: The central angle corresponding to the outline of the groove (6) is greater than the central angle corresponding to the outline of the boss (5).

7. The mechanism for limiting the rotational angle according to claim 1, characterized in that: The groove (6) is located on the end face of the elongated part (2), and the boss (5) is located on the end face of the annular part (1); or, the groove (6) is located on the end face of the annular part (1), and the boss (5) is located on the end face of the elongated part (2).

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