Motor front end cover detection tool

Abstract

The utility model discloses a motor front end cover detection frock, including base disk, positioning pin and a plurality of detection pin, the center of base disk upper surface is equipped with the positioning hole, and the positioning pin is installed in the positioning hole, and the positioning pin is connected with base disk through the screw mode, the first detection circumference of a certain diameter is evenly distributed a plurality of threaded holes to base disk upper surface, and the detection pin is installed in the threaded hole, and the detection pin is detachably connected with base disk through the screw mode, the second detection circumference that base disk upper surface still is provided with greater than the first detection circumference diameter, and the second detection circumference evenly distributed a plurality of spare threaded holes along the circumferential direction, the both sides of base disk are symmetrically provided with the piece taking recess. This frock can realize the quick positioning of motor front end cover and multi -parameter detection, including the comprehensive detection of hole position, aperture and depth, has simple structure, convenient operation, the flexible change type, and the advantages such as high detection efficiency, is applicable to the batch detection and assembly accuracy control of new energy automobile drive motor front end cover.

Description

Technical Field

[0001] This utility model relates to the field of hole position detection tooling technology, and in particular to a tooling for detecting the front cover of a motor. Background Technology

[0002] In the drive motor system of new energy vehicles, the front cover of the motor serves as a connector between the motor and the gearbox, and its geometric accuracy directly affects the assembly accuracy and operational stability of the entire vehicle's powertrain system. The front cover typically has 12 mounting holes for connecting to the gearbox housing. The distribution angle, diameter tolerance, and depth consistency of these holes are all key parameters ensuring the reliability of the bolt connection. Deviations in the hole distribution can lead to uneven bolt preload, resulting in loose connections, stress concentration, or noise and vibration. If the hole diameter exceeds tolerance, it affects the bolt fit accuracy, potentially causing incomplete tightening or insufficient engagement length, which in severe cases may lead to connection failure and pose a threat to the safe operation of new energy vehicles.

[0003] Current inspection methods primarily employ coordinate measuring machines (CMMs) or calipers for hole position and dimension measurement. While these methods offer high accuracy, they are complex to operate and have long inspection cycles, making them unsuitable for the high-paced production rhythms of motor manufacturing companies. CMMs are highly dependent on operator skill, and variations in measurements among different personnel make data consistency difficult to guarantee. Furthermore, the high cost and maintenance of the measuring equipment make them unsuitable for large-scale, rapid inspections on production lines. In addition, existing inspection methods often only allow for single-parameter inspections of hole position or diameter, failing to simultaneously evaluate multiple parameters such as hole position distribution, diameter, and depth in a single operation.

[0004] Therefore, there is an urgent need for a comprehensive testing fixture that is simple in structure, intuitive in inspection, highly efficient, and adaptable to front cover of different specifications, in order to meet the precision control and batch testing requirements of new energy vehicle motor assembly. Summary of the Invention

[0005] One objective of this invention is to provide a testing fixture for the front cover of a motor. This invention solves the problems of low testing efficiency, complex operation, and inability to simultaneously perform comprehensive testing of multiple parameters such as hole position, hole diameter, and hole depth in the prior art.

[0006] A motor front cover inspection fixture according to an embodiment of the present invention includes a base plate, a positioning pin, and several inspection pins. A positioning hole is formed at the center of the upper surface of the base plate, and a positioning pin is installed in the positioning hole. The positioning pin is connected to the base plate by a thread. Several threaded holes are evenly distributed along a first inspection circumference of a certain diameter on the upper surface of the base plate. Inspection pins are installed in the threaded holes, and the inspection pins are detachably connected to the base plate by a thread. A second inspection circumference larger than the diameter of the first inspection circumference is also provided on the upper surface of the base plate. Several spare threaded holes are evenly distributed along the circumferential direction of the second inspection circumference, and the spare threaded holes are used to install the inspection pins. Part-removing grooves are symmetrically provided on both sides of the base plate. Along the same diametrical direction of the base plate, the threaded holes on the first inspection circumference and the spare threaded holes on the second inspection circumference are collinear. Each inspection pin includes an integrally formed inspection section and a connecting section, and the inspection section is a cylindrical structure.

[0007] Preferably, the part-taking groove is recessed on both sides of the base plate, the radial radius of the part-taking groove is R0, the radius of the first detection circumference is R1, and the radius of the first detection circumference threaded hole (13) is R2, where R0 < R1 - R2, the height of the part-taking groove is one-third of the height of the base plate, the opening angle of the part-taking groove is α, which is 17°, and the outer arc length and inner arc length of the two part-taking grooves are both less than the arc length formed by connecting two adjacent spare threaded holes.

[0008] Preferably, the hole position parameters of the first detection circumference and the second detection circumference are the same, and the specifications, size and number of the threaded hole and the spare threaded hole are the same.

[0009] Preferably, 12 threaded holes are evenly distributed along the first detection circumference with a diameter of 480 mm along the upper edge of the base plate; and 12 spare threaded holes are evenly distributed along the second detection circumference with a diameter of 530 mm along the upper edge of the base plate.

[0010] Preferably, the diameter of the detection segment is 98% to 100% of the diameter of the mounting hole of the front end cover of the motor to be tested, the top circumference of the detection segment is provided with a first arc transition structure, and the total length of the detection segment is 1.5 times the depth of the mounting hole on the front end cover of the motor to be tested for connecting the gearbox housing.

[0011] Preferably, the total length of the detection segment is 45mm, and the surface of the detection segment is provided with axial scale lines, which are marked from 0 to 40mm.

[0012] Preferably, the connecting section of the detection pin has an external thread structure, the length of the connecting section is 20-22mm, and the connecting section is detachably connected to the threaded hole or spare threaded hole of the base plate by means of threads; the length of the threaded hole and spare threaded hole on the base plate is 2-3mm longer than the connecting section.

[0013] Preferably, the positioning pin includes a working section and a threaded connection section. The top circumference of the positioning pin is provided with a second arc transition structure for positioning in conjunction with the center hole of the front end cover of the motor. The length of the working section of the positioning pin is 1.5 times the depth of the center hole of the front end cover to be measured, and the threaded connection section is threaded in conjunction with the positioning hole of the base plate.

[0014] Preferably, the base plate is made of high-strength aluminum alloy or No. 45 steel, the detection pin and positioning pin are made of surface-hardened steel, and the outer surface of the detection section is chrome-plated or laser-hardened.

[0015] Preferably, the base plate has a disc-shaped structure, and the bottom surface of the base plate is provided with an anti-slip pad or rubber support feet; the positioning hole, threaded hole and spare threaded hole do not penetrate the base plate, and the depth of the positioning hole is adapted to the length of the threaded connection section of the positioning pin.

[0016] This utility model discloses a motor front cover inspection fixture. By designing two switchable inspection circumferential structures on the same base, it enables rapid inspection of front covers of different specifications, significantly improving inspection versatility. The threaded connection of the inspection pin structure ensures high detachability, facilitating maintenance and replacement. The laser scale design of the inspection section makes hole depth inspection visible, improving inspection accuracy and operational convenience. The part-removal groove structure optimizes manual operation space while meeting strength requirements, making front cover removal and placement safer and more efficient. The fixture has a compact overall structure, and the inspection process can complete multi-parameter inspection of hole position, diameter, and depth without complex adjustments, improving inspection efficiency several times compared to traditional methods. Simultaneously, the guiding structure of the positioning pin improves the stability of the inspection assembly, ensuring measurement repeatability and reliability. This utility model not only reduces reliance on the skills of inspection personnel but can also be integrated with automated assembly lines to achieve semi-automated inspection control, providing an efficient, economical, and reliable inspection method for the assembly accuracy of new energy vehicle motors. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of a motor front end cover inspection fixture according to the present invention; Figure 2 This is a top view of a motor front end cover inspection fixture according to the present invention; Figure 3 This is a front view of the inspection pin of a motor front cover inspection fixture according to this utility model; Figure 4 This is a three-dimensional structural diagram of the detection pin of a motor front cover detection fixture according to the present invention. Figure 5This is a schematic diagram of the structure of a motor front end cover according to Embodiment 1 of this utility model; In the diagram: 1-base plate, 2-positioning pin, 3-detection pin; 11-Spare threaded hole, 12-Part removal groove, 13-Threaded hole, 22-Second arc transition structure, 31-Detection section, 32-Connecting section, 33-First arc transition structure. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0019] Example 1

[0020] like Figure 1-4 As shown, a motor front cover inspection fixture according to an embodiment of the present invention includes a base plate 1, a positioning pin 2, and an inspection pin 3. The base plate 1 is the main component of the fixture, with an overall disc-shaped structure. Its upper surface is the inspection bearing surface of the motor front cover, and its lower surface is the support surface. A positioning hole is provided at the center of the upper surface of the base plate 1, and the positioning pin 2 is installed in the positioning hole. The bottom of the positioning pin 2 is fastened to the positioning hole in the center of the base plate 1 by a thread. This structure enables reliable disassembly and maintenance. A second arc transition structure 22 is provided on the top circumference of the positioning pin 2. The size of the second arc transition structure 22 is precisely matched with the center hole of the motor front cover to be tested, ensuring that the part to be tested can be smoothly inserted in the vertical direction and automatically correct its posture. The working section length of the positioning pin 2 is designed to be 1.5 times the depth of the center hole of the front cover to be tested. The threaded connection section is threadedly matched with the positioning hole of the base plate 1, ensuring that it still has sufficient guiding length and stability after positioning and insertion, thereby avoiding shaking or eccentricity during the inspection process. The locating pin 2 is made of surface-hardened steel to improve its wear resistance and service life. The base plate 1 is made of high-strength aluminum alloy or 45# steel; the detection pin 3 is made of surface-hardened steel, and the outer surface of the detection section 31 is chrome-plated or laser-hardened.

[0021] like Figure 1-2As shown, the upper surface of the base plate 1 has 12 threaded holes 13 evenly distributed along a first detection circumference with a diameter of 480 mm. These 12 threaded holes 13 are used to install detection pins 3. The distribution of the detection pins 3 corresponds one-to-one with the positions of the 12 bolt mounting holes on the front end cover of the motor to achieve positioning accuracy detection. The hole positions of the threaded holes 13 in the first detection circumference of the base plate 1 adopt an equiangular distribution design, with the central angle between adjacent detection pins 3 being 30°, thereby ensuring the consistency of the circumferential distribution. The base plate 1 also has a second detection circumference pre-set to adapt to another specification of front end cover. The diameter of the second detection circumference is 530 mm, and it also has 12 spare threaded holes 11 evenly distributed. The spare threaded holes 11 are arranged with the threaded holes of the first detection circumference as a common center. The two sets of detection circumferences share the same reference center, thereby ensuring that the center positioning of the front end cover is still based on the same coordinate system after the detection pin position is changed. The hole position parameters of the first and second inspection circumferences are completely consistent, including thread specifications, hole spacing tolerances, and hole depths, to ensure that the inspection pins 3 can be directly interchanged and that the inspection accuracy remains consistent.

[0022] To facilitate the placement and removal of the front cover by operators, symmetrical picking grooves 12 are provided on both sides of the base plate 1. The picking grooves 12 are recessed on both sides of the base plate 1, and their radial radius R0, height, and opening angle are designed to satisfy the relationship R0 < R1 - R2, where R1 is the radius of the first detection circumference, R2 is the radius of the threaded hole 13 of the first detection circumference, and the opening angle α is 17°. The height of the picking groove 12 is one-third of the height of the base plate 1. The outer arc length and inner arc length of the two picking grooves 12 are both less than the arc length formed by connecting two adjacent spare threaded holes 11. This design provides sufficient operating space for the operator's hands or clamps without affecting the overall strength of the base plate 1. The inner surface of the groove 12 is anodized or sandblasted to increase the coefficient of friction and prevent the front cover from slipping during handling.

[0023] like Figure 3-4As shown, the detection pin 3 is a key component for comprehensive detection of hole position, diameter, and depth. Each detection segment 31 is a cylindrical structure, and the detection pin 3 includes an integrally formed detection segment 31 and a connecting segment 32. The connecting segment 32 is a standard threaded segment, and its external thread specification is consistent with the threaded hole on the base plate 1, achieving fastening installation by screwing in. The top circumference of the connecting segment 32 is provided with a first arc transition structure 33 to avoid stress concentration during threaded connection. The diameter of the detection segment 31 is designed to be 98% to 100% of the diameter of the mounting hole of the front end cover of the motor to be tested, preferably 99%, to ensure accurate positioning during insertion without excessive tightness that would make disassembly difficult. The top circumference of the detection segment 31 is provided with a first arc transition structure 33 to facilitate insertion and prevent damage to the tested hole. The total length of the detection segment 31 is 1.5 times the depth of the mounting hole on the front end cover to be tested for connecting the gearbox housing, ensuring that a certain visible length is still retained at the top of the detection pin after insertion, facilitating operation and reading.

[0024] The outer surface of the detection section 31 is engraved with several equidistant axial graduation lines, marked from 0 to 40 mm. These graduation lines are formed by laser marking, which has the characteristics of wear resistance, clarity, and permanent marking. The spacing between each graduation line is 1 mm or optionally 0.5 mm. The operator can directly read the position of the graduation line at the opening of the front cover with the naked eye, thereby obtaining the actual value of the hole depth. The connecting section 32 of the detection pin 3 is provided with an external thread structure. The length of the connecting section 32 is 20-22mm. The connecting section 32 is detachably connected to the threaded hole 13 or the spare threaded hole 11 of the base plate 1 by means of threads. The length of the threaded hole 13 and the spare threaded hole 11 on the base plate 1 is 2-3mm longer than the connecting section 32, ensuring that the connecting section 32 is fully inserted into the hole and firmly engaged, avoiding loosening during the detection process. For motor front cover of different specifications, the detection pin 3 can be quickly adapted to the two specifications of φ480mm and φ530mm by simply switching between the two sets of circumferential threaded holes 13 and spare threaded holes 11 without adjusting the reference structure.

[0025] The scale marking of the detection section 31 is 40mm, while the thickness of a single cover is approximately 30mm. During testing, the front cover is attached to the upper surface of the base plate. After the detection section 31 is inserted into the threaded hole 13 or the spare threaded hole 11, the operator can quickly obtain the thickness data of the single cover by visually reading the scale value corresponding to the hole of the front cover. The total length of the detection section is 45mm, which extends 5mm beyond the end of the scale to avoid inserting too deeply and damaging the workpiece, while ensuring that the scale reading range completely covers the thickness to be measured.

[0026] The working principle of this utility model: like Figure 5The image shows the front cover of the motor under test. During testing, the operator first selects the appropriate circumferential testing position based on the specifications of the front cover (φ480 or φ530), and installs 12 testing pins 3 in the corresponding threaded holes 13 on the base plate 1. After installation, check whether the distribution of the testing pins 3 is uniform and perpendicular to the base plate surface. Once confirmed to be secure, testing can begin. Align the center hole of the front cover with the guide section of the positioning pin 2 and slowly press down until the front cover is completely flush with the upper surface of the base plate 1. During this process, the 12 testing pins 3 will be inserted into the 12 mounting holes of the front cover. If the hole distribution accuracy of the front cover meets the design requirements, all testing pins 3 can be smoothly inserted and remain perpendicular; if there is a hole deviation, some testing pins will be unable to be inserted or interference will occur, thus allowing for a direct assessment of the hole distribution error.

[0027] After inspection, the operator can read the hole depth value of the front cover by looking at the scale line position on the inspection pin 3. If the scale line readings are consistent, it indicates that the hole depth machining consistency is good; if the scale lines for individual hole depths show significant differences, it indicates that there is a deviation in the hole machining depth, and process re-inspection is required. Since the diameter of the inspection pin 3 is designed to closely match the hole diameter, the hole diameter size can be verified simultaneously during insertion. If the inspection pin 3 cannot be inserted or is inserted too loosely, it indicates that there is a deviation in the hole diameter. Through a single inspection process, the three key parameters of hole position, hole diameter, and hole depth can be detected simultaneously, significantly improving inspection efficiency.

[0028] After inspection, the operator can remove the front cover from the base plate 1 through the retrieval groove 12. The angle and position of the groove 12 are ergonomically optimized to ensure that the operator's hands can naturally enter the groove to grasp the edge of the front cover, reducing the risk of accidental injury and slippage. To adapt to batch inspection scenarios, the lower surface of the base plate 1 is equipped with anti-slip rubber feet or a vibration damping layer, making the inspection fixture stable on the table and unaffected by external disturbances. For production lines requiring automated inspection, positioning holes can be added to the bottom of the base plate to cooperate with automatic inspection tables or robotic grippers to achieve semi-automatic feeding and inspection.

[0029] The base plate 1 adopts an integral structure, made of 45# steel, with a surface hardness of HRC40-45 after heat treatment, and undergoes sandblasting and oxidation for rust prevention. The positioning pin 2 is made of 45# steel with a chrome-plated surface. This embodiment is suitable for motor front cover of φ480 and φ530 specifications, and specification switching can be completed by manually changing the position of the detection pin. The detection accuracy can be controlled within 0.05mm, and the detection cycle is approximately 15 seconds for a single manual inspection, which is about 10 times more efficient than traditional coordinate measuring machine inspection.

[0030] The bottom surface of the base plate 1 is provided with an anti-slip pad or rubber support feet to ensure that the tooling is stable and does not shift during the testing process, further enhancing the reliability of the positioning reference.

[0031] The positioning hole, threaded hole 13 and spare threaded hole 11 do not penetrate the base plate 1, and the depth of the positioning hole is adapted to the length of the threaded connection section of the positioning pin 2.

[0032] For motor front covers of different specifications, this fixture can be quickly adapted by changing the diameter of the detection pin and the position of the detection circumference. For example, when detecting a φ530mm front cover, simply unscrew the detection pin 3 from the first detection circumference position and install it into the spare threaded hole 11 on the second detection circumference to complete the specification switch. The whole process does not require additional calibration equipment and takes less than 2 minutes.

[0033] During testing, after the testing pin 3 is inserted into the front cover hole, the operator can read the hole depth through the scale. If a hole depth differs from other holes, it can be determined that there is a machining error in that hole. Since the insertion depth of the testing pin 3 corresponds one-to-one with the hole depth, the measurement repeatability is high, and it can replace some manual measuring tools for testing.

[0034] In summary, this fixture, through a seamless process of benchmark positioning, type change adaptation, insertion verification, and scale reading, eliminates the need for complex adjustments and specialized operating skills. It enables the detection of hole positions, diameters, and thicknesses on a single front-end cover, significantly improving detection efficiency compared to traditional methods and ensuring high data consistency. This invention offers significant advantages in multi-specification adaptation, rapid type change inspection, intuitive hole depth measurement, and ergonomic optimization. Its scientifically designed structure and mature manufacturing process demonstrate promising prospects for industrial application, making it suitable for batch assembly precision control of front-end covers for new energy vehicle drive motors. This inspection fixture can not only be used for inspecting front-end covers of new energy vehicle motors but can also be extended to other parts with multi-hole distribution characteristics, such as rear-end covers of motors, gearbox connecting flanges, and hydraulic pump covers, providing an efficient and reliable inspection solution for the machinery manufacturing field.

[0035] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. A tooling for inspecting the front cover of a motor, characterized in that, The system includes a base plate (1), a positioning pin (2), and several detection pins (3). A positioning hole is provided at the center of the upper surface of the base plate (1), and a positioning pin (2) is installed in the positioning hole. The positioning pin (2) is connected to the base plate (1) by a thread. Several threaded holes (13) are evenly distributed along a first detection circumference of a certain diameter on the upper surface of the base plate (1). Detection pins (3) are installed in the threaded holes (13), and the detection pins (3) are detachably connected to the base plate (1) by a thread. The upper surface of the base plate (1) is also provided with a diameter larger than the first detection circumference. The second detection circumference has a circumferential diameter and a number of spare threaded holes (11) are evenly distributed along the circumferential direction. The spare threaded holes are used to install the detection pin (3). The base plate (1) has symmetrically arranged part-taking grooves (12) on both sides. Along the same diameter direction of the base plate (1), the threaded holes (13) on the first detection circumference and the spare threaded holes (11) on the second detection circumference are collinear. The detection pin (3) includes an integrally formed detection section (31) and a connecting section (32). The detection section (31) is a cylindrical structure.

2. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The part-taking groove (12) is recessed on both sides of the base plate (1). The radial radius of the part-taking groove (12) is R0, the radius of the first detection circumference is R1, and the radius of the first detection circumference threaded hole (13) is R2, where R0 < R1 - R2. The height of the part-taking groove (12) is one-third of the height of the base plate (1). The opening angle of the part-taking groove (12) is α, which is 17°. The outer arc length and inner arc length of the two part-taking grooves (12) are both less than the arc length formed by connecting two adjacent spare threaded holes (11).

3. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The hole position parameters of the first detection circumference and the second detection circumference are the same, and the specifications, size and number of the threaded hole (13) and the spare threaded hole (11) are the same.

4. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The base plate (1) has 12 threaded holes (13) evenly distributed on the first detection circumference with a diameter of 480 mm along its upper edge; the base plate (1) has 12 spare threaded holes (11) evenly distributed on the second detection circumference with a diameter of 530 mm along its upper edge.

5. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The diameter of the detection section (31) is 98% to 100% of the diameter of the mounting hole of the front cover of the motor to be tested. The top circumference of the detection section (31) is provided with a first arc transition structure (33). The total length of the detection section (31) is 1.5 times the depth of the mounting hole on the front cover to be tested for connecting the gearbox housing.

6. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The detection section (31) has a total length of 45mm, and the surface of the detection section (31) is provided with axial scale lines, which are marked as 0-40mm.

7. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The connecting section (32) of the detection pin (3) is provided with an external thread structure. The length of the connecting section (32) is 20-22mm. The connecting section (32) is detachably connected to the threaded hole (13) or spare threaded hole (11) of the base plate (1) by means of thread. The length of the threaded hole (13) and spare threaded hole (11) on the base plate (1) is 2-3mm longer than the connecting section (32).

8. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The positioning pin (2) includes a working section and a threaded connection section. The top circumference of the positioning pin (2) is provided with a second arc transition structure (22) for positioning in conjunction with the center hole of the front cover of the motor. The length of the working section of the positioning pin (2) is 1.5 times the depth of the center hole of the front cover to be measured. The threaded connection section is threaded in conjunction with the positioning hole of the base plate (1).

9. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The base plate (1) is made of high-strength aluminum alloy or No. 45 steel, the detection pin (3) and the positioning pin (2) are made of surface-hardened steel, and the outer surface of the detection section (31) is chrome-plated or laser-hardened.

10. The inspection fixture for the front cover of a motor according to claim 1, characterized in that, The base plate (1) is a disc-shaped structure. The bottom surface of the base plate (1) is provided with an anti-slip pad or rubber support foot. The positioning hole, threaded hole (13) and spare threaded hole (11) do not penetrate the base plate (1), and the depth of the positioning hole is adapted to the length of the threaded connection section of the positioning pin (2).

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