Bevel gear pair backlash measuring and meshing coloring device

Abstract

The utility model discloses a bevel gear pair backlash measuring and meshing coloring device which comprises a base, a driving gear positioning detection assembly, a driven gear positioning detection assembly and a workpiece positioning clamping mechanism, and the driving gear positioning detection assembly, the driven gear positioning detection assembly and the workpiece positioning clamping mechanism are arranged on the base. The device further comprises a shaft system angle displacement assembly, and the shaft system angle displacement assembly is arranged on the base and can drive the driven gear positioning detection assembly to rotate around the workpiece positioning clamping mechanism. According to the device, the included angle and the axial telescopic length of the driving gear positioning detection assembly and the driven gear positioning detection assembly can be adjusted through the arrangement of the shaft system angle displacement assembly so as to adapt to the included angle between the driving gear input shaft and the driven gear output shaft and the length of the input shaft and the output shaft, the structure is simple, and the adaptability is high.

Description

Technical Field

[0001] This utility model relates to the field of precision mechanical workpiece measurement technology, specifically to a bevel gear backlash measurement and meshing coloring device. Background Technology

[0002] With the development of the aviation industry, helicopters have become widely used as an important type of aircraft. The mid- and tail gearboxes, as crucial components of the helicopter's transmission system, directly impact flight safety and stability. These gearboxes contain a pair of bevel gears, whose primary function is to transmit motion and power between two intersecting shafts. The included angle and length of the bevel gear pair shafts vary among different helicopter models. Traditionally, gear backlash measurement and meshing coloring in helicopter mid- and tail gearbox assembly are primarily performed manually. Backlash measurement is done manually using a dial indicator. Meshing coloring involves one person applying a resistive torque using a nylon belt or tooling while another person manually rotates and colors the gear. This traditional production method suffers from low accuracy, insufficient repeatability, low production efficiency, and high labor intensity.

[0003] Chinese patent document CN109682595A discloses a central gear pair meshing coloring device. In this device, a driving gear mounting assembly mounts the driving gear, and a driven gear mounting assembly mounts the driven gear. The driven gear meshes with the driving gear to form a central gear pair. While this device can perform coloring inspection of bevel gear pairs, the numerous models and specifications of reducers, along with varying angles between the driving and driven gears, make it unsuitable for the diverse testing needs of modern reducers. It cannot meet the requirements for backlash detection and meshing coloring, such as the angle between gears, gear mounting distance, gear axial force magnitude, and gear axial force direction. Furthermore, this device cannot simultaneously perform backlash detection and meshing coloring, resulting in low testing and assembly efficiency. Utility Model Content

[0004] This invention addresses the problems existing in the use of the prior art by providing a simple and adaptable bevel gear backlash measurement and meshing coloring device.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A bevel gear backlash measurement and meshing coloring device includes a base and a driving gear positioning and detection component, a driven gear positioning and detection component, and a workpiece positioning and clamping mechanism located on the base. It also includes a shaft system angle displacement component, which is disposed on the base and can drive the driven gear positioning and detection component to rotate around the workpiece positioning and clamping mechanism.

[0007] As a further improvement to the above technical solution:

[0008] The shaft angle displacement assembly includes an arc guide rail and an angle displacement drive component. The arc guide rail is mounted on a base and arranged around the workpiece positioning and clamping mechanism. The driven gear positioning and detection component is mounted on the arc guide rail. The angle displacement drive component is used to drive the driven gear positioning and detection component to move along the arc guide rail.

[0009] The active gear positioning detection component and the driven gear positioning detection component each include a positioning detection component. The positioning detection component includes a floating plate, a clamping component for clamping the gear, and a detector for measuring the gear rotation angle. The clamping component and the detector are disposed on the floating plate, and the floating plate is movably mounted on the base.

[0010] The positioning detection component also includes a balance cylinder, a transition plate, and a base plate. The balance cylinder is disposed on the transition plate, and the floating plate is raised and lowered on the transition plate by the balance cylinder. The transition plate is slidably disposed on the base plate. The base plate of the active gear positioning detection component is disposed on a base, and the base plate of the driven gear positioning detection component is slidably disposed on an arc guide rail.

[0011] The base is provided with a base linear slide rail, and the base plate of the active gear positioning and detection assembly is slidably mounted on the base linear slide rail.

[0012] The positioning detection component also includes a rotation drive component, which is used to drive the clamping component to rotate.

[0013] The positioning detection component also includes a moving drive component. The base plate is provided with a base plate linear slide rail. The moving drive component drives the transition plate to slide along the base plate linear slide rail and applies axial force to the gear.

[0014] The detector is an angle encoder.

[0015] The clamping component is a three-jaw chuck.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] This utility model's bevel gear backlash measurement and meshing coloring device, by setting a shaft angle displacement component, can adjust the included angle and axial extension length of the driving gear positioning detection component and the driven gear positioning detection component to adapt to the included angle between the driving gear input shaft and the driven gear output shaft, as well as the length of the input shaft and the output shaft. It can meet the automatic measurement and meshing coloring of bevel gear backlash for workpieces of different models and specifications. It can meet the motion stroke and functions required for backlash detection and meshing coloring, such as the included angle between gears, gear installation distance, gear axial force magnitude, and gear axial force direction requirements. It has a simple structure and strong adaptability. Attached Figure Description

[0018] Figure 1 This is a top view of the bevel gear backlash measurement and meshing coloring device of this utility model.

[0019] Figure 2 This is a side view of the bevel gear backlash measurement and meshing coloring device of this utility model.

[0020] Figure 3 This is a cross-sectional view of the active gear positioning and detection component in the bevel gear backlash measurement and meshing coloring device of this utility model.

[0021] Figure 4 This is a cross-sectional view of the driven gear positioning and detection component in the bevel gear backlash measurement and meshing coloring device of this utility model.

[0022] Legend:

[0023] 1. Base; 11. Base linear slide rail; 2. Driving gear positioning and detection assembly; 3. Driven gear positioning and detection assembly; 4. Workpiece positioning and clamping mechanism; 5. Shaft system angle displacement assembly; 51. Arc guide rail; 52. Angle displacement drive component; 6. Positioning detection component; 61. Floating plate; 62. Clamping component; 63. Detector; 64. Balance cylinder; 65. Transition plate; 66. Base plate; 661. Base plate linear slide rail; 67. Rotation drive component; 68. Movement drive component. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] In this utility model, unless otherwise explicitly specified and limited, the terms "assembly," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0028] like Figures 1 to 4 As shown, the bevel gear backlash measurement and meshing coloring device of this embodiment includes a base 1 and a driving gear positioning and detection component 2, a driven gear positioning and detection component 3 and a workpiece positioning and clamping mechanism 4 located on the base 1. It also includes a shaft system angle displacement component 5, which is disposed on the base 1 and can drive the driven gear positioning and detection component 3 to rotate around the workpiece positioning and clamping mechanism 4.

[0029] During backlash measurement and meshing coloring, the workpiece to be inspected (such as the intermediate or tail gearbox of a helicopter) is placed on the workpiece positioning and clamping mechanism 4. The workpiece is positioned and clamped on the workpiece positioning and clamping mechanism 4. At this time, the drive gear positioning and detection component 2 is coaxial with the drive gear. The drive gear positioning and detection component 2 positions and clamps the drive gear of the workpiece. The shaft angle displacement component 5 drives the driven gear positioning and detection component 3 to rotate around the workpiece positioning and clamping mechanism 4, so that the driven gear positioning and detection component 3 is coaxial with the driven gear of the workpiece. The driven gear positioning and detection component 3 positions and clamps the driven gear of the workpiece. The drive gear positioning and detection component 2 and the driven gear positioning and detection component 3 then perform backlash measurement and meshing coloring on the meshing drive gear and driven gear.

[0030] In this embodiment, the driving gear positioning detection component 2 is used to clamp the input shaft of the driving gear, and the driven gear positioning detection component 3 is used to clamp the output shaft of the driven gear.

[0031] The bevel gear backlash measurement and meshing coloring device of this embodiment can adjust the included angle and axial extension length of the driving gear positioning detection component 2 and the driven gear positioning detection component 3 by setting the shaft angle displacement component 5, so as to adapt to the included angle between the driving gear input shaft and the driven gear output shaft and the length of the input shaft and the output shaft. It can meet the automatic measurement of bevel gear backlash and meshing coloring of workpieces of different models and specifications. It can meet the motion stroke and functions required for backlash detection and meshing coloring, such as the included angle between gears, gear installation distance, gear axial force magnitude, and gear axial force direction requirements. It has a simple structure and strong adaptability.

[0032] Furthermore, in this embodiment, the shaft angle displacement assembly 5 includes an arc guide rail 51 and an angle displacement drive component 52. The arc guide rail 51 is disposed on the base 1 and arranged around the workpiece positioning and clamping mechanism 4. The driven gear positioning and detection assembly 3 is disposed on the arc guide rail 51, and the angle displacement drive component 52 is used to drive the driven gear positioning and detection assembly 3 to move along the arc guide rail 51. By setting the arc guide rail 51 arranged around the workpiece positioning and clamping mechanism 4, it is possible to accommodate workpieces with different included angles between the driving gear and the driven gear, and the driven gear positioning and detection assembly 3 can always be coaxial with the driven gear.

[0033] Preferably, in this embodiment, the arc guide rail 51 can meet the requirements for backlash measurement and meshing coloring of workpieces with an angle between the input shaft of the driving gear and the output shaft of the driven gear in the range of 80° to 145°.

[0034] Furthermore, in this embodiment, the driving gear positioning detection component 2 and the driven gear positioning detection component 3 each include a positioning detection component 6. The positioning detection component 6 includes a floating plate 61, a clamping component 62 for clamping the gear, and a detector 63 for measuring the rotation angle of the driving gear. The clamping component 62 and the detector 63 are disposed on the floating plate 61, which can be raised and lowered on the base 1. The clamping component 62 coaxially clamps the gear. Rotating the clamping component 62 of the driving gear positioning detection component 2 sequentially drives the input shaft of the driving gear, the output shaft of the driving gear, the driven gear, and the clamping component 62 of the driven gear positioning detection component 3 to rotate. The detectors 63 of the driving gear positioning detection component 2 and the driven gear positioning detection component 3 respectively measure the rotation angle of the driving gear and the driven gear to complete the backlash detection. Meanwhile, by setting the floating plate 61, it can adapt to different offset distances of the input shaft of the driving gear and the output shaft of the driven gear in different workpieces. By raising and lowering the floating plate 61 to adapt to different offset distances, the clamping part 62 of the driving gear positioning detection component 2 is always coaxially clamped with the input shaft of the driving gear, and the clamping part 62 of the driven gear positioning detection component 3 is always coaxially clamped with the output shaft of the driven gear. It has strong adaptability and high precision.

[0035] Furthermore, in this embodiment, the positioning detection component 6 also includes a balancing cylinder 64, a transition plate 65, and a base plate 66. The balancing cylinder 64 is disposed on the transition plate 65, and the floating plate 61 is raised and lowered on the transition plate 65 via the balancing cylinder 64. The transition plate 65 is slidably disposed on the base plate 66. The base plate 66 of the driving gear positioning detection component 2 is disposed on the base 1, and the base plate 66 of the driven gear positioning detection component 3 is slidably disposed on the arc guide rail 51. By having the transition plate 65 slidably disposed on the base plate 66, the components on the transition plate 65 of the driving gear positioning detection component 2 and the driven gear positioning detection component 3 can adapt to workpieces with different wheelbases, thus exhibiting strong adaptability. Simultaneously, the weight of all components on the balance transition plate 65 is balanced by the balance cylinder 64. When the clamping parts 62 of the drive gear positioning detection component 2 and the driven gear positioning detection component 3 clamp the gears respectively, the two balance cylinders 64 can adaptively adjust so that the clamping parts 62 of the drive gear positioning detection component 2 are coaxial with the input shaft of the drive gear, and the clamping parts 62 of the driven gear positioning detection component 3 are coaxial with the output shaft of the driven gear. This prevents the clamping parts 62 from falling due to the weight of each component, which would cause the clamping parts 62 of the drive gear positioning detection component 2 to deviate from the input shaft of the driven gear, and the clamping parts 62 of the driven gear positioning detection component 3 to deviate from the output shaft of the driven gear, thus improving the accuracy and flexibility of the device.

[0036] Preferably, a limiting plate is provided on the base plate 66 to prevent the transition plate 65 from coming off the base plate 66.

[0037] Preferably, multiple optical axis reinforcement seats are provided between the floating plate 61 and the transition plate 65, making the structure more stable.

[0038] Preferably, a polyurethane pad is provided on the transition plate 65, and the balance cylinder 64 is installed on the polyurethane pad, which makes the system more stable and the detection more accurate.

[0039] Furthermore, in this embodiment, a linear slide rail 11 is provided on the base 1, and the base plate 66 of the drive gear positioning and detection component 2 is slidably mounted on the linear slide rail 11. This facilitates the adaptation to workpieces with different wheelbases and also prevents interference between the workpiece and the drive gear positioning and detection component 2 when the workpiece positioning and clamping mechanism 4 is installing the workpiece, thus facilitating installation.

[0040] Furthermore, in this embodiment, the active gear positioning detection component 2 also includes a rotary drive component 67, which drives the clamping component 62 to rotate; the rotary drive component 67 of the driven gear positioning detection component 3 is used to provide a resisting torque to the clamping component 62. By applying the resisting torque, the state of the gear during the machining stage can be simulated, and the measurement results are more accurate.

[0041] Preferably, in this embodiment, the rotation drive 67 of the active gear positioning detection component 2 and the driven gear positioning detection component 3 is a servo motor and is mounted on the floating plate 61. During operation, the reverse torque of the rotation drive 67 of the driven gear positioning detection component 3 is set to 20 N.M.

[0042] Furthermore, in this embodiment, the active gear positioning and detection component 2 also includes a moving drive component 68. A base plate linear slide rail 661 is provided on the base plate 66. The moving drive component 68 drives the transition plate 65 to slide along the base plate linear slide rail 661 and applies axial force to the gear. By loading axial force, during detection, axial force is applied to the input shaft of the active gear and the output shaft of the driven gear to simulate the axial force state under real operation, and the measurement results are more accurate.

[0043] Preferably, the moving drive component 68 is a moving cylinder, and it is mounted on the second base plate 66 via a cylinder support, making the structure more stable.

[0044] Furthermore, in this embodiment, detector 63 is an angle encoder. By using an angle encoder instead of a traditional dial indicator for direct angle measurement, measurement errors caused by different dial indicator placement, operating habits, and probe positions are reduced, resulting in more accurate results. In this embodiment, two sets of angle encoders are provided: one set records the phase, and the other set records the pulse difference. By rotating the gear one revolution in both directions, the pulse difference on the same phase is obtained, and the gear backlash can be calculated. Using the angle encoder detection method, dynamic measurement of the full tooth backlash of a bevel gear pair can be achieved.

[0045] Furthermore, in this embodiment, the clamping member 62 is a three-jaw chuck. The result is simple and the clamping is stable.

[0046] Preferably, the bevel gear backlash measurement and meshing coloring device in this embodiment also includes an electrical control system. The electrical control system mainly consists of a control system and a safety system, such as a PLC, HMI, low-voltage electrical system, and safety light curtain, and is responsible for the motion control and logic operation of the entire device.

[0047] Preferably, the bevel gear backlash measurement and meshing coloring device of this embodiment also includes a data processing system. The data processing system consists of an industrial control computer, a data acquisition board, data processing software, etc., and is responsible for the acquisition, analysis, judgment, data storage, uploading and downloading, summarization, and report generation of data from various sensors of the entire device.

[0048] This utility model discloses a method for measuring and coloring the backlash of a bevel gear pair, which utilizes the bevel gear pair backlash measurement and meshing coloring device of this utility model and includes the following steps:

[0049] A1. Apply colorant to the tooth surface of the gear on the workpiece. After the workpiece is assembled, place the workpiece on the workpiece positioning and clamping mechanism. The workpiece positioning and clamping mechanism 4 positions and clamps the workpiece using a balance cylinder.

[0050] A2, the shaft angle displacement component 5 drives the driven gear positioning and detection component 3 to rotate along the workpiece positioning and clamping mechanism 4 to the designated position; specifically, the angle displacement drive component 52 drives the driven gear positioning and detection component 3 to move along the arc guide rail 51, and the two balance cylinders 64 supply air, so that the clamping component 62 of the driven gear positioning and detection component 3 is coaxial with the driven gear output shaft.

[0051] A3, the drive gear positioning detection component 2 and the driven gear positioning detection component 3 respectively clamp the drive gear end flange and the driven gear end flange, and apply axial force to the drive gear and the driven gear respectively; specifically, the moving drive component 68 of the moving drive gear positioning detection component 2 drives the transition plate 65 to slide along the linear slide rail 661 of the base plate, and makes the clamping component 62 of the drive gear positioning detection component 2 approach the drive gear, the moving drive component 68 of the driven gear positioning detection component 3 drives the transition plate 65 to slide along the linear slide rail 661 of the base plate, and makes the clamping component 62 of the driven gear positioning detection component 3 approach the driven gear, the drive gear positioning detection component 2 and the driven gear positioning detection component 3 respectively clamp the drive gear and the driven gear, and apply axial force to the drive gear and the driven gear respectively;

[0052] A4, the active gear positioning detection component 2 drives the active gear to rotate, and the driven gear positioning detection component applies a resisting force to the driven gear. At the same time, the active gear positioning detection component 2 and the driven gear positioning detection component 3 measure the rotation angle of the two gears respectively, calculate the gear clearance, and complete the bevel gear pair tooth backlash measurement and meshing coloring. Specifically, the active gear positioning detection component 2 drives the active gear to rotate forward until the speed is constant. After maintaining the constant speed and rotating at least one revolution in the circle, the active gear is driven to rotate in the reverse direction. The driven gear positioning detection component 3 applies a certain resisting torque to the driven gear. The detector 63 simultaneously measures the rotation angle of the active gear and the driven gear respectively, calculates the gear clearance, and completes the tooth backlash measurement. After the active gear rotates one revolution in both directions, the two clamping parts 62 are released, the two rotating driving parts 67 stop, and the two moving driving parts 68 drive the transition plate 65 to retract respectively. The workpiece positioning clamping mechanism 4 is released, the workpiece is removed, the meshing mark is checked and recorded, and the meshing coloring is completed. In other embodiments, a multi-point uniform measurement method can also be selected. The angle encoder collects pulse data at regular angle intervals, performs multi-point uniform measurement, and outputs curve data in real time, achieving high measurement accuracy (≤0.004mm). Simultaneously, the device can also perform single-point backlash measurement of the gear pair by fixing one end and swinging the other end left and right, similar to manual measurement, and output multi-point backlash.

[0053] The bevel gear backlash measurement and meshing coloring method of this embodiment, by driving the driven gear positioning and detection component 3 to move along the arc guide rail 51, adapts to different included angles between the input shaft of the driving gear and the output shaft of the driven gear, as well as the lengths of the input and output shafts. This allows for automatic measurement of bevel gear backlash and meshing coloring of workpieces of different models and specifications. The method is simple to operate and highly adaptable. By setting up a balancing cylinder 64 for ventilation, the clamping component 62 is prevented from falling due to the weight of each component, causing the clamping component 62 of the driving gear positioning and detection component 2 and the driven gear positioning and detection component 3 to deviate from the input shaft of the driving gear and the output shaft of the driven gear, respectively, improving the accuracy and flexibility of the device. By applying axial force during detection, the axial force on the driving gear and driven gear is simulated under actual operating conditions, resulting in more accurate measurement results. By applying a resisting torque, the stress state of the gear during machining can be simulated, further improving the accuracy of the measurement results. This method has the advantages of strong adaptability, high accuracy, high flexibility, and accurate measurement results.

[0054] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present utility model using the methods and techniques disclosed above, or modify it into equivalent embodiments with equivalent changes, without departing from the spirit and technical solution of the present utility model. Therefore, any simple modifications, equivalent substitutions, equivalent changes and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the content of the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A bevel gear backlash measurement and meshing coloring device, comprising a base (1) and a driving gear positioning and detection assembly (2), a driven gear positioning and detection assembly (3), and a workpiece positioning and clamping mechanism (4) located on the base (1), characterized in that: It also includes a shaft angle displacement assembly (5), which is mounted on the base (1) and can drive the driven gear positioning detection assembly (3) to rotate around the workpiece positioning clamping mechanism (4).

2. The bevel gear backlash measurement and meshing coloring device according to claim 1, characterized in that: The shaft angle displacement assembly (5) includes an arc guide rail (51) and an angle displacement drive (52). The arc guide rail (51) is mounted on the base (1) and arranged around the workpiece positioning and clamping mechanism (4). The driven gear positioning and detection assembly (3) is mounted on the arc guide rail (51). The angle displacement drive (52) is used to drive the driven gear positioning and detection assembly (3) to move along the arc guide rail (51).

3. The bevel gear backlash measurement and meshing coloring device according to claim 2, characterized in that: The active gear positioning detection component (2) and the driven gear positioning detection component (3) each include a positioning detection component (6). The positioning detection component (6) includes a floating plate (61), a clamping component (62) for clamping the gear, and a detector (63) for measuring the gear rotation angle. The clamping component (62) and the detector (63) are disposed on the floating plate (61), and the floating plate (61) is movably disposed on the base (1).

4. The bevel gear backlash measurement and meshing coloring device according to claim 3, characterized in that: The positioning detection component (6) further includes a balance cylinder (64), a transition plate (65), and a base plate (66). The balance cylinder (64) is disposed on the transition plate (65). The floating plate (61) is raised and lowered on the transition plate (65) by the balance cylinder (64). The transition plate (65) is slidably disposed on the base plate (66). The base plate (66) of the active gear positioning detection component (2) is disposed on the base (1). The base plate (66) of the driven gear positioning detection component (3) is slidably disposed on the arc guide rail (51).

5. The bevel gear backlash measurement and meshing coloring device according to claim 4, characterized in that: The base (1) is provided with a base linear slide rail (11), and the base plate (66) of the active gear positioning and detection assembly (2) is slidably mounted on the base linear slide rail (11).

6. The bevel gear backlash measurement and meshing coloring device according to claim 4, characterized in that: The positioning detection component (6) further includes a rotation drive component (67), which is used to drive the clamping component (62) to rotate; the rotation drive components (67) of the active gear positioning detection component (2) and the driven gear positioning detection component (3) drive rotation in opposite directions.

7. The bevel gear backlash measurement and meshing coloring device according to claim 6, characterized in that: The positioning detection component (6) also includes a moving drive component (68). The base plate (66) is provided with a base plate linear slide rail (661). The moving drive component (68) drives the transition plate (65) to slide along the base plate linear slide rail (661) and applies axial force to the gear.

8. The bevel gear pair backlash measurement and meshing coloring device according to any one of claims 3-7, characterized in that: The detector (63) is an angle encoder.

9. The bevel gear backlash measurement and meshing coloring device according to any one of claims 3-7, characterized in that: The clamping component (62) is a three-jaw chuck.

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