Triggerable axial backstop mechanism
By designing a triggerable axial check mechanism, the check tongue is triggered to contact the inner ring of the bearing by inertial force, which solves the problem of the bearing returning to its fixed position under high overload conditions and improves the stability of the system-level protection structure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING UNIV OF TECH
- Filing Date
- 2023-09-30
- Publication Date
- 2026-07-21
AI Technical Summary
Existing check mechanisms are inadequate to ensure that bearings can accurately and reliably return to their original position after sliding axially under high overload conditions, and they cannot prevent secondary sliding.
A triggerable axial check mechanism was designed. It utilizes a combination structure of housing, check tongue, limit bolt and trigger limit pin. The check tongue is triggered by inertial force to pop out and contact the inner ring of the bearing, which compensates for machining and assembly errors and achieves reliable bearing fixation.
Under high overload conditions, the bearing is reliably fixed by triggering unlocking through inertial force and compensating for errors with the arc surface design of the check tongue, thereby improving the stability of the high overload system-level protection structure.
Smart Images
Figure CN117145860B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of triggerable check mechanisms, and specifically to a triggerable axial check mechanism suitable for preventing axial movement of bearings in high overload-resistant system-level protection structures. Background Technology
[0002] High-dynamic aircraft navigation systems operate under harsh conditions of overload, high temperature, and high pressure. To meet the testing requirements of this system and improve the stability of the high-overload system-level protection structure, the bearings in the high-overload system-level protection structure need to return to their original position and be fixed after axial sliding to prevent secondary sliding. Existing anti-return mechanisms can block the return action after sliding, but they cannot meet the requirement that the bearings can return to their original position and prevent secondary sliding. How to make the bearings return after axial sliding and be accurately and reliably fixed in their original position has become a technical problem to be solved. Summary of the Invention
[0003] To address the aforementioned issues, this invention provides a triggerable axial check mechanism. This mechanism allows the bearing to move axially in a ready state, while restricting the axial movement of the bearing after activation. Furthermore, the structural design compensates for certain clearance errors caused by assembly and machining, thereby improving the stability of the high overload-resistant system-level protection structure.
[0004] A triggerable axial check mechanism includes a housing, a check tongue, a limiting bolt, a trigger limiting pin, and a compression spring. The housing has a countersunk screw hole, a limiting bolt hole, a trigger limiting pin hole, and a central hole, and has a top curved surface coaxial with the shaft and having the same radius. The limiting bolt hole is a stepped hole, and the limiting bolt mates with the stepped hole. The stepped hole has a first stepped hole and a second stepped hole with radial dimensions decreasing sequentially from the outside to the inside. The limiting bolt is threaded into the second stepped hole. The trigger limiting pin hole is a through hole, and the trigger limiting pin is clearance-fitted or transition-fitted with the trigger limiting pin hole. The trigger limiting pin is a cylindrical pin at one end and a tapered pin at the other end. The central hole has the same cross-sectional shape as the check tongue, and the check tongue presses down on the compression spring installed in the central hole. The check tongue and the housing form a sliding pair.
[0005] The check tongue has a symmetrical structure, with a circular arc surface at the top having the same radius as the shaft, and a compression spring guide post at the bottom. The stop surfaces on both sides are curved surfaces with a certain angle, which is less than twice the friction angle. The curved surfaces have the same curvature as the shaft, and the plane containing the curvature normal is perpendicular to the shaft end face. The check tongue has a guide groove on one side and a pin hole on the other side. The length of the guide groove is the required ejection distance of the check mechanism. The pin hole has the same radius as the trigger limit pin hole of the housing and is coaxial.
[0006] The check valve has a rectangular cross-section with rounded corners. The cross-section of the central hole is the same as that of the check valve. The cross-sections of the stepped hole and the pin hole are circular.
[0007] In the untriggered state, the limit bolt is at the bottom of the guide groove, the end face of the cylindrical end of the trigger limit pin is in contact with the check tongue, the top arc surface of the check tongue is flush with the housing, and the top arc surface of the housing is flush with the shaft.
[0008] In the triggered state, the limit bolt is at the top of the guide groove, triggering the limit pin to disengage from the check mechanism, the check tongue pops out, and the arc surface of the check tongue contacts the inner ring line of the bearing.
[0009] This invention relates to a triggerable axial check mechanism suitable for preventing axial movement of bearings in high overload protection systems. The check mechanism housing is mounted on a shaft. From left to right, the housing is sequentially equipped with a limit bolt, a check tongue, a trigger limit pin, and a compression spring mounted on the guide post of the check tongue. The large inertial force generated by the system causes the trigger limit pin to disengage from the mechanism, releasing the lock on the check tongue. The check tongue slides in contact with the housing and pops out under the action of the compression spring and is limited by the limit bolt. The side of the check tongue contacts the inner ring line of the bearing. The tilt angle and curvature of the side eliminate the gaps caused by machining and assembly errors, improving the stability of the high overload protection system.
[0010] The advantages of this invention are:
[0011] 1. In environments with overload and high pressure, this invention can trigger unlocking using inertial force. By adjusting the stiffness and compression of the compression spring, along with tolerances and friction coefficients, the triggering force can be controlled, making the triggering safe and reliable.
[0012] 2. The arc surface design of the check tongue can compensate for machining and assembly errors and gaps, making it in line contact with the inner ring of the bearing rather than point contact, thus ensuring stable check performance.
[0013] 3. The present invention has a simple structure and is easy to implement and promote. Attached Figure Description
[0014] Figure 1 Schematic diagram of the structure of the present invention
[0015] Figure 2 Schematic diagram of a high overload resistant system-level protection structure
[0016] Figure 3 Diagram of the stop tongue structure
[0017] Figure 4 Detailed view of the curved surface of the stop tongue
[0018] Figure 5 Shell structure diagram
[0019] The above figures include the following reference numerals:
[0020] 1. Housing; 11. Countersunk screw hole; 12. Limit bolt hole; 13. Trigger limit pin hole; 14. Central core hole; 2. Check tongue; 21. Top arc surface; 22. Bottom guide post; 23. Stop surface; 24. Guide groove; 25. Pin hole; 3. Limit pin; 4. Compression spring; 5. Limit bolt; 6. External structure; 61. Axial check mechanism; 62. Bearing; 63. Shaft. Detailed Implementation
[0021] The present invention will now be described with reference to the accompanying drawings and embodiments, but the present invention is not limited to the following embodiments.
[0022] This invention provides a simple and easy-to-operate triggerable axial check mechanism, which is used in high overload system-level protection structures to prevent bearings from moving axially. The structure includes a housing 1, a check tongue 2, a limit pin 3, a compression spring 4, and a limit bolt 5.
[0023] It should be noted that the triggering device in the embodiment of the present invention is to activate the trigger limit pin 3 and disengage it from the trigger limit pin hole 13 by the huge inertial force generated by high overload, without the need for an additional power device or power source.
[0024] In the above technical solution, multiple mechanisms are evenly distributed around the shaft, which increases the reliability of the check valve.
[0025] Preferably, in an embodiment of the present invention, the two mechanisms are symmetrically distributed on the axis with an included angle of 180°. The number and distribution of the mechanisms can also be multiple, depending on actual needs.
[0026] like Figure 1 and Figure 2 As shown, the housing 1 is fixed to the shaft 63 by countersunk screws through countersunk screw holes 11. The check tongue 2 presses against the compression spring 4 and is placed in the central hole 14 of the housing 1. The clearance fit forms a sliding pair. The limit bolt 5 ensures that the check tongue 2 can only slide within a limited range.
[0027] In the untriggered state, the limit bolt 5 is at the bottom of the guide groove 24, the end face of the cylindrical end of the trigger limit pin 3 contacts the check tongue 2, the top arc surface of the check tongue 2 is flush with the housing, and the top arc surface of the housing 1 is flush with the shaft 63; in the triggered state, the limit bolt 5 is at the top of the guide groove 24, the trigger limit pin 3 disengages from the check mechanism, the check tongue 2 pops out, and the arc surface of the check tongue 2 contacts the inner ring line of the bearing 62.
[0028] Furthermore, the triggering device uses the enormous inertial force generated by the high overload of the system to actuate the trigger limit pin 3 and disengage it from the trigger limit pin hole 13.
[0029] like Figure 3 and Figure 4 As shown, the check tongue 2 has a symmetrical structure with a rectangular cross-section, rounded corners, a top arc surface 21 with the same radius as the shaft, and a compression spring guide post 22 at the bottom. The left and right stop surfaces are stop surfaces 23 with a certain angle, which is less than twice the friction angle. The curved surface has the same curvature as the shaft. The check tongue has a guide groove 24 on one side and a pin hole 25 on the other side. The length of the guide groove is the required ejection distance of the check mechanism. The pin hole 25 has the same radius as the limit bolt hole 12 and is coaxial.
[0030] Furthermore, the stop surface 23 is designed to compensate for machining and assembly errors, and it makes line contact with the inner ring of the bearing 62 rather than point contact, thus ensuring stable anti-return performance.
[0031] like Figure 5 As shown, the housing has a countersunk screw hole 11, a limit bolt hole 12, a trigger limit pin hole 13, and a central hole 14, and has a top curved surface coaxial with the shaft 63 and having the same radius. The limit bolt hole 12 is a stepped hole, and the limit bolt 5 mates with the stepped hole. The stepped hole has a first stepped hole and a second stepped hole with radial dimensions decreasing sequentially from the outside to the inside. The limit bolt 5 is threaded into the second stepped hole. The trigger limit pin hole 13 is a through hole, and the trigger limit pin 3 is clearance-fitted or slightly transition-fitted with the trigger limit pin hole 13. The cross-sectional shape of the central hole 14 is the same as that of the check tongue 2.
[0032] As can be seen from the above description, the above embodiments of the present invention achieve the following technical effects: when the check tongue in the present invention is not triggered, it is locked in the housing. After the system is activated, a huge inertial force is generated, causing the limit pin to disengage from the check mechanism, releasing the lock of the check tongue. The check tongue pops out, thereby limiting the axial movement of the bearing and effectively improving the stability of the high overload system-level protection structure.
[0033] The terms "top," "bottom," "vertical," "horizontal," "up and down," and "left and right" used in this invention are used to express the relative positional relationship of the relevant structures, and are not limitations on the absolute orientation of the relevant structures.
[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention.
Claims
1. A triggerable axial check mechanism, characterized in that: The system includes a housing, a check valve, a limit bolt, a trigger limit pin, and a compression spring. The housing has a countersunk screw hole, a limit bolt hole, a trigger limit pin hole, and a central hole, and has a top curved surface coaxial with the shaft and having the same radius. The limit bolt hole is a stepped hole, and the limit bolt mates with the stepped hole. The stepped hole has a first stepped hole and a second stepped hole with radial dimensions decreasing sequentially from the outside to the inside. The limit bolt is threaded into the second stepped hole. The trigger limit pin hole is a through hole. The trigger limit pin mates with the trigger limit pin hole with a clearance fit or transition. The mechanism includes: a trigger limit pin with a cylindrical pin at one end and a tapered pin at the other end; the cross-sectional shape of the central hole is the same as that of the check tongue; the check tongue presses against the compression spring installed in the central hole; the check tongue and the housing form a sliding pair; in the triggerable axial check mechanism, the triggering device uses the huge inertial force generated by the high overload of the system to actuate the trigger limit pin and disengage it from the trigger limit pin hole, thereby releasing the check tongue from its lock and ejecting it from the housing. The stop surface of the check tongue contacts the inner ring of the bearing, preventing the bearing from moving axially and improving the stability of the high overload system-level protection structure.
2. The triggerable axial check mechanism according to claim 1, characterized in that: The check tongue has a symmetrical structure, with an arc surface at the top having the same radius as the shaft, a compression spring guide post at the bottom, and stop surfaces on both sides. The check tongue has a guide groove on one side and a pin hole on the other side. The length of the guide groove is the required ejection distance of the check mechanism. The pin hole has the same radius as the trigger limit pin hole of the housing and is coaxial.
3. The triggerable axial check mechanism according to claim 2, characterized in that: The left and right sides of the check tongue are stop surfaces. The stop surfaces are curved surfaces with a certain angle to the vertical direction. The angle is less than twice the friction angle. The curved surfaces have the same curvature as the axis curvature. The plane containing the curvature normal is perpendicular to the end face of the axis.