Special tool for measuring bearing clearance of airplane wheel

Abstract

The utility model discloses a special tool for measuring the bearing clearance of an airplane wheel and a measuring method, which belong to the technical field of aviation equipment and comprise a pressing block, a straight rod, a weight and a base. The straight rod is fixed on the base, the airplane wheel penetrates through the straight rod and falls on the base, the weight of the weight is 73.5 N, the penetrating straight rod is pressed on a bearing on the upper side of the airplane wheel, the pressing block is inserted into the straight rod from the side face to press the weight, and the dial indicator is installed at the top end of the straight rod to measure the position change of the upper surface of the pressing block. During measurement, the height of the upper surface of the pressing block is measured when the bush is not installed, the height of the upper surface of the pressing block is measured again after the bush is installed, and the difference value between the two times is the bearing clearance. According to the utility model, the stability and the accuracy of the axial measurement of the airplane wheel bearing are realized through mechanical operation, the purpose of measuring the axial clearance through independent operation by one person is realized, and the force application is uniform, so that the maintenance quality of an airplane is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of aviation equipment technology and relates to a special tooling for measuring the clearance of aircraft wheel bearings. Background Technology

[0002] During a major overhaul of a certain type of aircraft, it is necessary to measure the clearance between two bearings on the nose landing gear wheel to determine whether the bushing installed between the bearings meets the requirements. The process requirement is to measure the axial clearance of the bearings under a force of 73.5N, and the bearing clearance should be (0.12~0.18)mm. The existing tooling method involves manually applying force by pressing the bearing with a handheld spring force gauge. During operation, the manual pressing force must be uniform and accurate. Since the wheel diameter is approximately φ230mm and the weight is approximately 10kg, the required force is relatively large. At the same time, the stability of the wheel must be ensured during measurement. This method cannot be operated by one person alone and requires at least two operators to work together. Therefore, there is an urgent need for tooling specifically designed for measuring the axial clearance of the wheel bearings. Utility Model Content

[0003] In view of this, the present invention provides a special tooling machine and method for measuring the clearance of aircraft wheel bearings, so as to realize the measurement of the clearance of aircraft wheel bearings of this type, and ensure the quality and safety of aircraft overhaul.

[0004] The present invention adopts the following technical solution:

[0005] A special tooling for measuring the clearance of aircraft wheel bearings includes a positioning screw 1, a dial indicator base 2, a pressure block 3, a straight rod 4, a weight 5, a base 6, a fixing nut 7, and a chassis 8.

[0006] The base 6 is a hollow cylinder with an open bottom. Its top outer diameter is set according to the diameter of the wheel bearing. A threaded through hole is made in the center of the top surface. Its bottom outer circle is fixedly connected to the annular base 8.

[0007] The diameter of the straight rod 4 is set according to the inner hole of the wheel bearing. It has a radial through hole at its upper part, which is a vertically arranged elongated strip. The center of the upper end face of the straight rod 4 has a mounting hole that communicates with the strip-shaped through hole. The lower end of the straight rod 4 is provided with a coaxial threaded post with a small diameter, which is used to fasten the connection with the threaded through hole on the top surface of the base 6. The lower end of the threaded post passes through the bottom of the threaded through hole of the base 6, and the protruding part is screwed with a fixing nut 7 to strengthen the fastening between the straight rod 4 and the base 6 and improve stability. After the wheel bearing passes through the straight rod 4, it rests on the base 6.

[0008] The weight 5 has a weight of 73.5N and a through hole in its center. The diameter of the through hole is set according to the outer diameter of the straight rod 4. After the weight 5 is inserted into the straight rod 4, it presses against the wheel bearing. After insertion, the upper end face of the weight 5 is located at the radial through hole at the top of the straight rod 4. A pressure block 3 is inserted into the radial through hole to press the weight 5 tightly. To ensure that the force of the weight only acts on the wheel bearing, a boss is provided in the middle of the bottom surface of the weight 5. The diameter of the boss is set according to the diameter of the wheel bearing.

[0009] The dial indicator base 2 is inserted into the mounting hole at the top of the straight rod 4 for the insertion of the dial indicator. The side wall of the dial indicator base 2 has a threaded hole, and a positioning screw 1 is installed in the threaded hole to fix the dial indicator. The dial indicator measuring head is attached to the top surface of the pressure block 3 for measuring the height change of the pressure block 3, thereby obtaining the bearing clearance.

[0010] The beneficial effects of this utility model are as follows: This utility model achieves stability and accuracy in axial measurement of aircraft wheel bearings through mechanical operation, realizes the purpose of measuring axial clearance by one person alone, and applies force evenly, thereby ensuring the quality of aircraft maintenance. Attached Figure Description

[0011] Figure 1 This is a diagram illustrating the effect of using this utility model.

[0012] Figure 2 This is a schematic diagram of the straight rod of this utility model.

[0013] Figure 3 This is a schematic diagram of the weights used in this utility model.

[0014] Figure 4 This is a schematic diagram of the base of this utility model.

[0015] Figure 5 This is a schematic diagram of the measurement process of this utility model.

[0016] Among them, 1-positioning screw; 2-dial gauge base; 3-pressure block; 4-straight rod; 5-weight; 6-base; 7-fixing nut; 8-chassis; 9-bushing. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the specific embodiments of this utility model will be described in detail below.

[0018] A special tooling for measuring the clearance of aircraft wheel bearings, such as Figure 1 As shown, it includes a positioning screw 1, a dial indicator base 2, a pressure block 3, a straight rod 4, a weight 5, a base 6, a fixing nut 7, and a chassis 8.

[0019] like Figure 4As shown, the base 6 is a hollow cylinder with an open bottom. Its top outer diameter is set according to the diameter of the wheel bearing. A threaded through hole is made in the center of the top surface. Its bottom outer circle is fixedly connected to the annular base 8. To reduce the processing difficulty, the base 6 and the base 8 are processed separately and then welded into one piece to ensure that the bottom surface is level.

[0020] like Figure 2 As shown, the diameter of the straight rod 4 is set according to the inner hole of the wheel bearing. It has a radial through hole on its upper part, which is a vertically arranged elongated strip. The center of the upper end face of the straight rod 4 has a mounting hole that communicates with the strip-shaped through hole. The lower end of the straight rod 4 is provided with a coaxial threaded post with a small diameter, which is used to fasten the connection with the threaded through hole on the top surface of the base 6. The lower end of the threaded post passes through the bottom of the threaded through hole of the base 6, and the protruding part is screwed with a fixing nut 7 to strengthen the fastening between the straight rod 4 and the base 6 and improve stability. After the wheel bearing passes through the straight rod 4, it rests on the base 6.

[0021] like Figure 3 As shown, the weight 5 has a weight of 73.5N and a central through hole. The diameter of the through hole is set according to the outer diameter of the straight rod 4. After the weight 5 is inserted into the straight rod 4, it presses against the wheel bearing to apply force evenly to the bearing. After insertion, the upper end face of the weight 5 is located at the radial through hole at the top of the straight rod 4. A pressure block 3 is inserted into the radial through hole to press the weight 5 tightly. To ensure that the force of the weight acts only on the wheel bearing, a boss is provided in the middle of the bottom surface of the weight 5. The diameter of the boss is set according to the diameter of the wheel bearing. The dimensions of the weight 5 are calculated and then machined. After machining, the weight is repeatedly measured until it is guaranteed to be 73.5N ± 1N.

[0022] The dial indicator base 2 is inserted into the mounting hole at the top of the straight rod 4 for the insertion of the dial indicator. The side wall of the dial indicator base 2 has a threaded hole, and a positioning screw 1 is installed in the threaded hole to fix the dial indicator. The dial indicator measuring head is attached to the top surface of the pressure block 3 for measuring the height change of the pressure block 3.

[0023] The usage process is as follows:

[0024] Step 1: Insert the un-shielded wheel into the straight rod 4 and place it on the base 6. Insert the weight 5 into the straight rod 4 and press it onto the upper surface of the wheel bearing. Insert the pressure block 3 to press the weight 5.

[0025] Step 2: Install the dial indicator in the dial indicator holder 2 and insert it into the mounting hole at the top of the straight rod 4, so that the dial indicator measuring head is in contact with the top surface of the pressure block 3 and the dial indicator is zeroed.

[0026] Step 3: Remove the dial indicator along with its base 2, then remove the wheel and install a bushing between its two bearings. Repeat Step 1 to re-insert the wheel into the straight rod 4 and install the weights 5 and pressure block 3. Figure 5 .

[0027] Step 4: Insert the dial indicator holder 2, which is equipped with a dial indicator, into the mounting hole at the top of the straight rod 4, so that the dial indicator measuring head is in contact with the top surface of the pressure block 3. The dial indicator reading is the clearance between the two bearings. The bearing clearance should be (0.12~0.18) mm. Determine whether the measured value meets the requirements. If it does not meet the requirements, adjust the bushing length until the requirements are met.

[0028] In summary, the above are merely preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A special tooling for measuring the clearance of aircraft wheel bearings, characterized in that, Includes pressure block (3), straight rod (4), weights (5), and base (6); The base (6) is a hollow cylinder with an open bottom. Its top outer diameter is set according to the diameter of the wheel bearing, and a threaded through hole is made in the center of the top surface. The diameter of the straight rod (4) is set according to the inner hole of the wheel bearing. A radial through hole is made on its upper part. The through hole is a vertically arranged long strip. A mounting hole communicating with the strip through hole is made at the center of the upper end face of the straight rod (4) for mounting a dial indicator. A coaxial threaded column with a small diameter is provided at the lower end of the straight rod (4) for fastening to the threaded through hole on the top surface of the base (6). After the wheel bearing passes through the straight rod (4), it falls on the base (6). The weight (5) has a through hole in the center, and the diameter of the through hole is set according to the outer diameter of the straight rod (4). A boss is set in the middle of the bottom surface of the weight (5), and the diameter of the boss is set according to the diameter of the wheel bearing. After the weight (5) is inserted into the straight rod (4), it is pressed on the wheel bearing. After insertion, the upper end face of the weight (5) is located at the radial through hole in the upper part of the straight rod (4). A pressure block (3) is inserted into the radial through hole to press the weight (5). The dial indicator measuring head is attached to the top surface of the pressure block (3) to measure the height change of the pressure block (3) and thus obtain the bearing clearance.

2. The special tooling for measuring the clearance of aircraft wheel bearings according to claim 1, characterized in that, The bottom outer circle of the base (6) is fixedly connected to the annular base (8).

3. The special tooling for measuring the clearance of aircraft wheel bearings according to claim 1, characterized in that, The lower end of the threaded rod (4) protrudes from the bottom of the threaded through hole of the base (6), and a fixing nut (7) is screwed onto the protruding part to improve stability.

4. The special tooling for measuring the clearance of aircraft wheel bearings according to claim 1, characterized in that, The weight (5) has a weight of 73.5 N.

5. A special tooling for measuring the clearance of aircraft wheel bearings according to claim 1, characterized in that, It also includes a dial indicator base (2) inserted into the mounting hole at the top of the straight rod (4) for inserting the dial indicator. The dial indicator base (2) has a threaded hole on its side wall, and a positioning screw (1) is installed in the threaded hole to fix the dial indicator.

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