Rotary potentiometer anti-rotation redundancy structure and mounting method

Abstract

The application discloses a rotary potentiometer anti-rotation redundancy structure and a mounting method, relates to the field of potentiometer mounting, and is characterized by comprising a positioning groove and a limiting gasket. A groove is formed in the bottom of a mounting hole of a rudder shell, the periphery of a potentiometer body is connected with at least two fan-shaped supporting lugs, the fan-shaped supporting lugs are located in the groove, a first waist-shaped hole is formed in the fan-shaped supporting lugs, and a fixing screw is connected with the rudder shell by penetrating through the first waist-shaped hole. The positioning groove is formed in the edge position of the groove in the bottom of the rudder shell, and the limiting gasket is connected to one end of the fan-shaped supporting lugs and clamped to the other end of the positioning groove. The connection reliability of the potentiometer body and the rudder shell is improved.

Description

Technical Field

[0001] This application relates to a redundancy structure and installation method for preventing rotation of a rotary potentiometer, specifically a redundancy design for preventing rotation of the rotary potentiometer body within a limited space, belonging to the technical field of potentiometer installation structures. Background Technology

[0002] As an important angular displacement measuring unit for servo motors, the potentiometer's housing is fixed by a potentiometer clamp or connecting screws; while the output shaft is rigidly or elastically connected to the unit under test. The rotation of the unit under test drives the potentiometer's output shaft to rotate, which in turn drives the sliding brush (fixed to the potentiometer's output shaft) to slide on the conductive plastic resistive body, ultimately outputting a voltage value that matches the deflection angle.

[0003] Currently, low-to-medium power harmonic servos such as the 114003 and A series all use the WDD32S-X (X=1, 2, 4), and their structural form is as follows: Figure 1 As shown, the potentiometer body is fixed to the servo housing (hereinafter referred to as the housing) by a potentiometer clamp; the outline of the potentiometer is shown in the figure below. Figure 2 As shown; the structural diagram of the potentiometer clamp is as follows. Figure 3 As shown, after the potentiometer clamp deforms under stress, the contact area between the potentiometer clamp and the potentiometer body is relatively small; at the same time, the contact area between the potentiometer and the servo housing is also relatively small. This results in a certain number of servos experiencing mechanical zero-position misalignment due to the deflection of the potentiometer body during mechanical environment tests such as random vibration and qualification vibration tests with the servo. The deviation of the servo's mechanical zero position will eventually cause the initial deflection angle of the air rudder, which will then affect the roll control of the aircraft. Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a redundant structure and installation method for preventing rotation of a rotary potentiometer, so as to improve the connection reliability between the potentiometer body and the servo housing.

[0005] The technical solution of this invention is:

[0006] A redundancy structure for preventing rotation of a rotary potentiometer is disclosed. The potentiometer body is installed in the mounting hole of a servo housing through the redundancy structure, including a positioning groove and a limiting gasket. A groove is provided at the bottom of the mounting hole of the servo housing. At least two fan-shaped lugs are connected to the outer periphery of the potentiometer body. The fan-shaped lugs are located in the groove. A first oblong hole is provided on the fan-shaped lug. A fixing screw passes through the first oblong hole and is connected to the servo housing. The positioning groove is provided at the edge of the groove at the bottom of the servo housing. One end of the limiting gasket is connected to the fan-shaped lug, and the other end is locked in the positioning groove.

[0007] The fan-shaped lugs are evenly distributed around the circumference of the potentiometer body.

[0008] The limiting washer and the fan-shaped support are fixed by a locking screw. At least one fan-shaped support has a positioning threaded hole. The limiting washer has a second oblong hole. The locking screw passes through the second oblong hole and is connected to the positioning threaded hole.

[0009] The limiting pad includes a connecting part and an insertion part. The connecting part is located on the side of the fan-shaped support ear away from the bottom of the servo housing. The insertion part is connected to the connecting part and inserted into the positioning groove. The insertion part cooperates with the positioning groove, which is a "U"-shaped groove. The end of the positioning groove away from the groove axis is arc-shaped. The insertion part can rotate within the positioning groove about the central axis of the positioning groove.

[0010] The insertion part is connected to the end of the connecting part near the second waist-shaped hole.

[0011] The direction from the center of the end of the second waist-shaped hole near the insertion part to the insertion part is the first direction, and the direction from the center of the end of the second waist-shaped hole near the insertion part to the center of the other end of the second waist-shaped hole is the second direction. The angle between the first direction and the second direction is 0°-40°.

[0012] A method for installing a rotary potentiometer anti-rotation redundancy structure, wherein the potentiometer body and the servo motor housing have any of the aforementioned rotary potentiometer anti-rotation redundancy structures, including...

[0013] S1: Place the potentiometer body into the mounting hole of the servo housing, and use the fixing screw to pass through the first oblong hole and connect to the servo housing for pre-tightening to ensure that the potentiometer body can deflect under the action of external force. After mechanically zeroing the potentiometer body, tighten the fixing screw.

[0014] S2: Insert one end of the adjusting shim into the positioning groove, align the second oblong hole of the other end with the positioning threaded hole on the potentiometer body, and use a locking screw to pass through the second oblong hole and connect it to the fan-shaped support.

[0015] In summary, this application includes at least the following beneficial technical effects:

[0016] By combining the "limiting plate" and the "positioning screw", the contradiction between zero-position adjustment of the potentiometer body and anti-rotation of the potentiometer body is overcome. The "limiting plate" can realize limited angle adjustment of the potentiometer body, and the "positioning screw" makes the potentiometer body and the limiting plate rigidly connected, connecting the potentiometer body and the housing together, realizing anti-rotation of the rotating potentiometer body, thus forming a redundant structure. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the potentiometer assembly.

[0018] Figure 2 This is an outline drawing of the WDD32S series potentiometer;

[0019] Figure 3 Here is a structural diagram of the potentiometer clamp;

[0020] Figure 4 The diagram shows the structure of the servo housing before and after adding the "U"-shaped positioning structure. Figure 4 a is before the addition of the "U"-shaped positioning structure. Figure 4 b represents the addition of a "U"-shaped positioning structure;

[0021] Figure 5 A schematic diagram of the potentiometer's sector-shaped lugs and positioning thread structure;

[0022] Figure 6 A schematic diagram of the shim structure for adjustment;

[0023] Figure 7 This is a schematic diagram of the potentiometer body and the servo motor housing assembly;

[0024] Figure 8 This is a three-dimensional structural diagram of the servo motor housing;

[0025] Figure 9 This is a three-dimensional structural diagram of the potentiometer body;

[0026] Figure 10 A three-dimensional structural diagram of the potentiometer body and the servo motor housing after assembly;

[0027] Figure 11 Schematic diagram of the adjustment range of the limit shim in its free state;

[0028] Explanation of reference numerals in the attached drawings: 1. Potentiometer body; 2. Servo housing; 3. Mounting hole; 4. Positioning groove; 5. Limiting washer; 6. Groove; 7. Fan-shaped support lug; 8. First oblong hole; 9. Second oblong hole; 10. Fixing screw; 11. Positioning threaded hole; 12. Connecting part; 13. Insertion part; 14. Locking screw;

[0029] 21. Potentiometer clamp; 22. Potentiometer output shaft; 23. Potentiometer clamp mounting slot. Detailed Implementation

[0030] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments:

[0031] Addressing the current single-point connection between the potentiometer body and the servo motor housing, and considering the actual space dimensions of the servo motor and the potentiometer debugging process, this application discloses a redundant structure and installation method for preventing rotation of a rotary potentiometer. Figure 4 As shown, the redundant structure includes a positioning groove 4 and a limiting pad 5.

[0032] like Figures 5-9As shown, a circular groove 6 is provided at the bottom of the mounting hole 3 of the servo housing 2. At least two fan-shaped lugs 7 are connected to the outer circumference of the potentiometer body 1. The fan-shaped lugs 7 are located in the groove 6, and the potentiometer body 1 with the fan-shaped lugs 7 can rotate within the groove 6. The fan-shaped lugs 7 are evenly distributed around the circumference of the potentiometer body 1. A first oblong hole 8 is provided on the fan-shaped lug 7, and a fixing screw 10 passes through the first oblong hole 8 to connect with the servo housing 2. The setting of the fan-shaped lugs 7 increases the contact area between the potentiometer body 1 and the housing, thereby increasing the frictional torque that prevents the potentiometer body 1 from deflecting, making the fixation of the potentiometer body 1 more stable. At the same time, the first oblong hole provided on the fan-shaped lug 7 can meet the mechanical zeroing requirements of the potentiometer body 1.

[0033] The positioning groove 4 is located at the edge of the groove 6 at the bottom of the servo housing 2. One end of the limiting pad 5 is connected to the fan-shaped support 7, and the other end is locked in the positioning groove 4.

[0034] The limiting washer 5 and the sector-shaped support 7 are fixed together by a locking screw 14. At least one sector-shaped support 7 has a positioning threaded hole 11. The limiting washer 5 has a second oblong hole 9. The locking screw 14 passes through the second oblong hole 9 and is connected to the positioning threaded hole 11. The locking screw 14, through its positioning function, secures the limiting washer 5 to the potentiometer body 1. The locking screw 14 can be a countersunk screw or a non-countersunk screw.

[0035] The limiting pad 5 includes a connecting part 12 and an insertion part 13. The connecting part 12 is located on the side of the fan-shaped support 7 away from the bottom of the servo housing 2. The insertion part 13 is connected to the connecting part 12 and inserted into the positioning groove 4. The insertion part 13 cooperates with the positioning groove 4. The positioning groove 4 is a "U" shaped groove. The end of the positioning groove 4 away from the axis of the groove 6 is arc-shaped. The insertion part 13 can rotate within the positioning groove 4 and about the central axis of the positioning groove 4.

[0036] The insertion part 13 is connected to the connecting part 12 near one end of the second oblong hole 9. The direction from the center of the second oblong hole 9 near the end of the insertion part 13 to the insertion part 13 is the first direction, and the direction from the center of the second oblong hole 9 near the end of the insertion part 13 to the center of the other end of the second oblong hole 9 is the second direction. The angle between the first direction and the second direction is 0°-20° (e.g., ...). Figure 11 (As shown). Under the premise of ensuring that the limiting pad 5 and the fan-shaped support 7 can be connected through the second waist-shaped hole 9, the limiting pad 5 can rotate a large angle in the positioning groove 4, and the second waist-shaped hole 9 does not need to be too long.

[0037] like Figure 6As shown, when the potentiometer body 1 is adjusted within a certain angle range, the positioning threaded hole 11 on the potentiometer body 1 needs to be allowed to deflect with a designed rotation radius R. If the rotation radius R is increased, so that the center of the positioning threaded hole 11 on the potentiometer body 1 is far away from the rotation center of the limiting pad 5, then within the same adjustment range, the length of the second oblong hole 9 needs to be increased; if the rotation radius R is decreased, so that the center of the positioning threaded hole 11 on the potentiometer body 1 is close to the rotation center of the potentiometer body 1, then within the same adjustment range, the length of the second oblong hole 9 can be decreased. However, in order to ensure a safety barrier between the locking screw 14 and the potentiometer body 1, the minimum size of R is limited by the outer dimensions of the potentiometer body 1 housing and the size of the countersunk screw. Based on the above analysis, the adjustable range of the potentiometer body 1 is limited by the structural dimensions, and the relevant structural dimensions have certain constraints on each other. In this application, the structural dimensions of the potentiometer are set to ensure that the limiting pad 5 does not interfere with the outer wall of the potentiometer body 1, and to ensure that both the potentiometer body 1 and the limiting pad 5 can rotate.

[0038] This invention uses a U-shaped positioning groove 4 to limit the positioning of the limiting pad 5, but the structural design of the limiting pad 5 allows for adjustment and rotation within a small range. A redundant fastening between the potentiometer body 1 and the housing is achieved through a "transfer method".

[0039] like Figure 4 As shown, the "U"-shaped positioning groove 4 added to the servo housing 2 achieves a limiting structure similar to a "pin". Since a fully positioned shaft hole cannot meet the mechanical zeroing requirements of the potentiometer body 1, the present invention adds a "U"-shaped positioning groove 4 to the housing. This structure provides a positioning axis while not affecting the degree of freedom of the "pin (limiting washer 5)" in a specific direction. The "U"-shaped positioning groove 4 on the housing provides a positioning axis and allows the "pin (limiting washer 5)" to deflect in a specific direction to meet the mechanical zeroing requirements of the potentiometer body 1. A positioning threaded hole 11 is added to the sector-shaped support 7, using a wire thread sleeve (locking screw 14) to increase the connection rigidity between the limiting washer 5 and the sector-shaped support 7.

[0040] like Figure 6 As shown, the limiting shim 5 is a key component of the redundant structure. One end of it matches the "U"-shaped structure of the housing, which can limit the axis of the adjusting shim and allow the adjusting shim to deflect within a certain range (±15°). The other end is fastened to the potentiometer body 1 by a fastening screw.

[0041] In summary, to solve the problems of potentiometer body 1 "not locking" and "single point" issues, this patent mainly proposes two measures:

[0042] 1. Increase the frictional torque between the potentiometer body 1 and the housing:

[0043] To increase the friction between the potentiometer body 1 and the housing, it is necessary to ensure the contact area between them. The previous structure only had local contact, and the lever arm of the friction force was small. Even if the preload was large enough, the friction torque generated was relatively limited, which is why it could not be "locked". Therefore, it is necessary to increase the contact area and thus increase the lever arm of the friction force.

[0044] 2. Add redundancy measures

[0045] The previous structure used a potentiometer clamp for "single-point" locking, which posed a risk of "misalignment". Especially under the action of "alternating load" of vibration, the preload of the potentiometer clamp changes, and there is a possibility of switching between static friction and dynamic friction, which may lead to "single-point" unlocking and cause the potentiometer body 1 to gradually deflect. Therefore, it is necessary to add redundancy measures to limit the relative position of the potentiometer body 1 and prevent accumulation when "misalignment" occurs.

[0046] Installation methods include:

[0047] First, install the potentiometer body 1 inside the servo housing 2 and pre-tighten it with a cylindrical head screw to ensure that the potentiometer body 1 can deflect under external force. Then, mechanically zero the potentiometer body 1. After the resistance between the sliding point of the potentiometer body 1 and the power supply terminal meets the requirements, tighten the fixing screw 10 and confirm according to the tightening torque requirements.

[0048] Next, install one end of the adjusting shim into the positioning groove 4 of the housing; align the second oblong hole 9 at the other end with the positioning threaded hole 11 on the potentiometer body 1;

[0049] Finally, the locking screw 14 is used to fasten the limiting washer 5 to the potentiometer body 1, forming a redundant structure: that is, when the frictional torque between the potentiometer body 1 and the housing meets the test requirements, the potentiometer body 1 remains stationary; when the potentiometer body 1 tends to rotate relative to the housing, due to the rigid connection between the limiting washer 5 and the potentiometer body 1, the "U"-shaped structure of the housing restricts the deflection of the limiting washer 5, and reduces the fitting accuracy (0.02mm gap) between the housing positioning groove 4 and the limiting washer 5 through the lever arm (a=sqrt(11.82+182)=21.52), thus limiting the potentiometer body 1 to a small range (0.04°). Figure 10 and Figure 11 As shown.

[0050] By using an anti-rotation redundancy structure, the potentiometer body 1 is connected to the housing as a whole, thereby achieving "anti-rotation" of the potentiometer body 1.

[0051] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims of the present invention.

Claims

1. A rotary potentiometer anti-rotation redundancy structure, wherein the potentiometer body (1) is mounted in the mounting hole (3) of the servo housing (2) through the redundancy structure, characterized in that: Includes positioning groove (4) and limiting gasket (5), The bottom of the mounting hole (3) of the servo housing (2) is provided with a groove (6), and at least two fan-shaped lugs (7) are connected to the outer periphery of the potentiometer body (1). The fan-shaped lugs (7) are located in the groove (6), and a first waist-shaped hole (8) is provided on the fan-shaped lugs (7). The fixing screw (10) passes through the first waist-shaped hole (8) and is connected to the servo housing (2). The positioning groove (4) is located at the edge of the groove (6) at the bottom of the servo housing (2). One end of the limiting pad (5) is connected to the fan-shaped support (7), and the other end is locked in the positioning groove (4). The limiting pad (5) and the fan-shaped support (7) are fixed together by a locking screw (14). At least one fan-shaped support (7) has a positioning threaded hole (11). The limiting pad (5) has a second waist-shaped hole (9). The locking screw (14) passes through the second waist-shaped hole (9) and is connected to the positioning threaded hole (11). The limiting pad (5) includes a connecting part (12) and an insertion part (13). The connecting part (12) is located on the side of the fan-shaped support (7) away from the bottom of the servo housing (2). The insertion part (13) is connected to the connecting part (12) and inserted into the positioning groove (4). The insertion part (13) cooperates with the positioning groove (4). The positioning groove (4) is a "U" shaped groove. The end of the positioning groove (4) away from the axis of the groove (6) is arc-shaped. The insertion part (13) can rotate in the positioning groove (4) with the central axis of the positioning groove (4) as the axis.

2. The anti-redundancy structure for a rotary potentiometer according to claim 1, characterized in that: The fan-shaped lugs (7) are evenly distributed around the potentiometer body (1).

3. The anti-redundancy structure for a rotary potentiometer according to claim 1, characterized in that: The insertion part (13) is connected to the end of the connecting part (12) near the second waist-shaped hole (9); the second waist-shaped hole (9) is an arc-shaped hole coaxial with the potentiometer body.

4. The anti-redundancy structure for a rotary potentiometer according to claim 1, characterized in that: The direction from the center of the end of the second waist-shaped hole (9) near the insertion part (13) to the center of the insertion part (13) is the first direction, and the direction from the center of the end of the second waist-shaped hole (9) near the insertion part (13) to the center of the other end of the second waist-shaped hole (9) is the second direction. The angle between the first direction and the second direction is 0°-40°.

5. A method for installing a rotary potentiometer anti-redundancy structure, characterized in that: The potentiometer body and the servo housing have a rotary potentiometer anti-rotation redundancy structure as described in any one of claims 1-4, including... S1: Place the potentiometer body (1) in the mounting hole (3) of the servo housing (2), and use the fixing screw (10) to pass through the first waist-shaped hole (8) and connect to the servo housing (2) for pre-tightening to ensure that the potentiometer body (1) can deflect under the action of external force. After mechanically zeroing the potentiometer body (1), tighten the fixing screw (10). S2: Place one end of the limiting pad into the positioning groove (4), align the second waist-shaped hole (9) at the other end with the positioning threaded hole (11) on the potentiometer body (1), and pass the locking screw (14) through the second waist-shaped hole (9) and connect it with the fan-shaped support (7).

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