Frameless motor test fixture

Abstract

A frameless motor test tool, comprising: a mounting mechanism, comprising a shell assembly and a rotating shaft assembly; a receiving chamber is formed in the shell assembly, and the rotating shaft assembly is arranged through the receiving chamber and is rotationally connected with the shell assembly; a detection mechanism, comprising a mounting cover, a first encoder and a second encoder, the mounting cover is arranged opposite to the shell assembly along the axial direction of the rotating shaft assembly; the first encoder is arranged in the mounting cover and is fixedly arranged on the rotating shaft assembly, and is used for detecting the running data of the stator and the rotor; and the second encoder is fixedly arranged on the mounting cover and is used for receiving the feedback data of the frameless motor. Since two encoders, i.e., the first encoder and the second encoder, are arranged in the detection mechanism, the accuracy of the test tool can be improved, and the encoders can also detect and correct each other, so that the test precision of the encoders can be improved, and the product yield of the frameless motor can be improved.

Description

Technical Field

[0001] This application relates to the field of motor technology, specifically to a frameless motor testing fixture. Background Technology

[0002] Frameless motors offer advantages such as small size, light weight, low inertia, and the ability to provide high power at high speeds. With the aid of various speed reducers, they can achieve even higher torque. Frameless motors are widely used in applications such as robot joints and medical devices where motors must operate within confined spaces. However, before being put into use, frameless motors can only undergo performance testing using external tooling. Furthermore, testing typically involves data acquisition using only a single encoder, resulting in poor accuracy, and the precision of the single encoder itself cannot be guaranteed. Utility Model Content

[0003] The main technical problem this application addresses is the poor testing accuracy of frameless motors and the lack of guaranteed encoder accuracy in related technologies.

[0004] To address the aforementioned technical problems, this application provides a frameless motor testing fixture, wherein the frameless motor includes a stator and a rotor nested together; the testing fixture includes:

[0005] The mounting mechanism includes a housing assembly and a rotating shaft assembly; the housing assembly has a receiving chamber, the rotating shaft assembly is disposed through the receiving chamber and is rotatably connected to the housing assembly, and the rotating shaft assembly is used for mounting the stator and rotor of the frameless motor thereon;

[0006] The detection mechanism includes a mounting cover, a first encoder, and a second encoder. The mounting cover is disposed opposite to the housing assembly along the axial direction of the rotating shaft assembly. The first encoder is located inside the mounting cover and fixedly disposed on the rotating shaft assembly, and is used to detect the operating data of the stator and rotor. The second encoder is fixedly disposed on the mounting cover and is used to receive feedback data from the frameless motor.

[0007] In one embodiment, a third encoder is further included, which is disposed opposite to the first encoder along the axial direction. The third encoder is located inside the mounting cover and is fixedly disposed on the rotating shaft assembly.

[0008] In one embodiment, a circuit board is further included, which is located between the first encoder and the third encoder, and the circuit board is fixedly connected to the housing assembly.

[0009] In one embodiment, the mounting cover has a perforated structure.

[0010] In one embodiment, the mounting cover includes a plurality of support columns that extend radially and are fixedly connected, and the gaps between the support columns form the hollow structure.

[0011] In one embodiment, the second encoder is fixedly disposed on the outside of the mounting cover along the axial direction.

[0012] In one embodiment, the first encoder includes a code disk encoder, and the second encoder includes an optical encoder.

[0013] In one embodiment, the rotating shaft assembly includes a rotating shaft member and a baffle. The rotating shaft member has a flange on one side along the axial direction. The flange is distributed circumferentially along the rotating shaft member and protrudes radially outward. The baffle is disposed opposite to the flange along the axial direction, and the baffle is detachably connected to the rotating shaft member. The flange and the baffle cooperate with each other to clamp and fix the rotor.

[0014] In one embodiment, the housing assembly includes a detachably connected housing body, a front cover, and a rear cover, the housing body, the front cover, and the rear cover enclosing the receiving chamber; the rotating shaft assembly has a first connecting portion and a second connecting portion extending axially, the first connecting portion and the second connecting portion being rotatably connected to the front cover and the rear cover, respectively.

[0015] In one embodiment, the shell body is provided with at least one mounting hole communicating with the receiving chamber, and a fastener movably connected to the mounting hole; the fastener extends radially into the receiving chamber and is used to abut and fix against the outer wall of the stator.

[0016] According to the frameless motor testing fixture in the embodiments of this application, since the testing mechanism is equipped with two encoders, a first encoder and a second encoder, the accuracy of the testing fixture can be improved. Moreover, the encoders can also detect and calibrate each other, thereby improving the testing accuracy of the encoders in this application and thus improving the product yield of the frameless motor. Attached Figure Description

[0017] Figure 1 This application provides a schematic diagram of the frameless motor testing fixture structure.

[0018] Figure 2 A cross-sectional view of a frameless motor testing fixture in an embodiment of this application.

[0019] Figure 3 This application embodiment presents a schematic diagram of the detection mechanism structure in the frameless motor testing fixture.

[0020] Figure 4 This application embodiment contains a cross-sectional view of the testing mechanism assembly.

[0021] Figure 5 The structural diagram of the rotating shaft assembly in the embodiments of this application is shown.

[0022] Figure 6 This application provides an embodiment of the housing assembly cross-sectional view.

[0023] Explanation of reference numerals in the attached figures:

[0024] 1-Mounting mechanism; 11-Housing assembly; 111-Housing body; 112-Front end cover; 113-Rear end cover; 12-Spindle assembly; 121-Spindle component; 122-Baffle; 123-Flange; 124-First connecting part; 125-Second connecting part; 13-Assembly hole; 14-Fastener;

[0025] 2-Detection mechanism; 21-Mounting cover; 22-First encoder; 23-Second encoder; 24-Third encoder; 25-Circuit board; 26-Hollowed-out structure; 27-Support column;

[0026] 31-Stator; 32-Rotor. Detailed Implementation

[0027] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0028] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0029] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0030] Frameless permanent magnet synchronous motors (PMSMs) offer advantages such as small size, light weight, low inertia, and the ability to provide high power at high speeds. Furthermore, with the assistance of various speed reducers, they can achieve even higher torque. Frameless PMSMs are widely used in applications requiring motors to operate within confined spaces, such as robot joints and medical devices. Because frameless PMSMs share bearings and housings with the equipment they are mounted on, their design lacks front and rear end covers, housings, and bearings. Therefore, external tooling is essential for pre-shipment performance testing of frameless motors. Traditional frameless motor testing fixtures only use a single encoder to collect data, resulting in poor accuracy due to a lack of verification methods, and the encoder's own precision cannot be guaranteed.

[0031] To address the aforementioned issues, this application provides a frameless motor testing fixture, please refer to [reference needed]. Figure 1 and Figure 2 This frameless motor testing fixture is used for performance testing of frameless motors. The frameless motor has a stator 31 and a rotor 32 nested together, that is, the stator 31 is fitted onto the rotor 32. The frameless motor testing fixture includes:

[0032] The mounting mechanism 1 includes a housing assembly 11 and a rotating shaft assembly 12. The housing assembly 11 has a receiving chamber for accommodating the stator 31, and the housing assembly 11 is fixedly connected to the stator 31. The rotating shaft assembly 12 is disposed through the receiving chamber and is rotatably connected to the housing assembly 11. The rotating shaft assembly 12 is used for mounting the stator 31 and rotor 32 of the frameless motor.

[0033] The detection mechanism 2 includes a mounting cover 21, a first encoder 22, and a second encoder 23. The mounting cover 21 is arranged opposite to the housing assembly 11 along the axial direction of the shaft assembly 12. The first encoder 22 is located inside the mounting cover 21 and fixedly mounted on the shaft assembly 12, and is used to detect the operating data of the stator 31 and the rotor 32. The second encoder 23 is fixedly mounted on the mounting cover 21 and is used to receive feedback data from the frameless motor.

[0034] The frameless motor testing fixture in this embodiment is used to test the performance parameters of a frameless motor. The frameless motor under test includes a stator 31 and a rotor 32 that are nested together. The stator 31 is fitted onto the outer periphery of the rotor 32, and the stator 31 and the rotor 32 can rotate relative to each other.

[0035] When testing frameless motors, due to the unique structure of frameless motors, the testing fixture needs to provide a normal operating environment for the motor. Therefore, the testing fixture includes a mounting mechanism 1, which includes a housing assembly 11 and a shaft assembly 12, used to fixably connect with the stator 31 and rotor 32 of the frameless motor, respectively, thereby establishing the required operating environment for the frameless motor. In other words, in this embodiment, the housing assembly 11 in the mounting mechanism 1 is used to form a fixed connection with the stator 31 of the frameless motor, and the shaft assembly 12 in the mounting mechanism 1 is used to form a fixed connection with the rotor 32 of the frameless motor. The rotor 32 and the stator 31 can rotate relative to each other axially, and the shaft assembly 12 and the housing assembly 11 can also rotate relative to each other in the same direction.

[0036] A receiving chamber is formed within the housing assembly 11 to accommodate the stator 31 and the rotor 32, with the stator 31 and rotor 32 nested together. The stator 31 and rotor 32 are fixedly connected to the housing assembly 11, meaning their positions and orientations are relatively fixed after connection and generally will not change before testing is completed. It is worth noting that the connection between the stator 31 and the housing assembly 11 should be detachable, allowing the stator 31 to be installed in the receiving chamber and the frameless motor to be removed from the testing fixture after testing. In other words, in this embodiment, the stator 31 and housing assembly 11 form a detachable fixed connection. "Detachable" means the connection between the stator 31 and housing assembly 11 can be removed, while "fixed connection" means that in the connected state, the positions of the stator 31 and housing assembly 11 are relatively fixed and will not move relative to each other when the connection is removed.

[0037] The rotating shaft assembly 12 is disposed through the receiving chamber and is fixedly connected to the rotor 32, meaning that the rotating shaft assembly 12 and the rotor 32 can rotate together. Specifically, the rotating shaft assembly 12 is disposed through the receiving chamber because its main body passes through the chamber, and both ends are rotatably connected to the housing assembly 11 forming the receiving chamber, allowing the rotating shaft assembly 12 to rotate axially relative to the housing assembly 11. In other words, in this embodiment, the frameless motor is installed using an mounting structure to facilitate subsequent testing of the frameless motor.

[0038] For performance testing of frameless motors, please refer to [reference needed]. Figure 3 and Figure 4The testing fixture in this embodiment further includes a detection mechanism 2, which comprises a mounting cover 21, a first encoder 22, and a second encoder 23. The first encoder 22 and the second encoder 23 indicate that this embodiment has two devices for detecting the performance parameters of the frameless motor. The first encoder 22 is fixedly mounted on the shaft assembly 12 and can rotate with the shaft assembly 12, allowing data to be read during rotation. The second encoder 23 is fixedly mounted on the mounting cover 21. Based on the arrangement of the first encoder 22 and the second encoder 23, both encoders can read the performance parameters of the frameless motor. Considering the detection results of both encoders comprehensively, the test results can be more accurate. Moreover, the test results of the two encoders can be mutually verified. If the accuracy of the test result of one encoder is low, it can be corrected by the test result of the other encoder. This improves both the accuracy of the frameless motor test and the testing precision of the encoders involved in the test, thereby improving the testing experience and increasing the yield rate of the frameless motor.

[0039] In some alternative embodiments, please refer to Figure 3 and Figure 4 To further improve the testing accuracy of the frameless motor, a third encoder 24 may be included. The third encoder 24 is axially opposed to the first encoder 22, located inside the mounting cover and fixedly mounted on the shaft assembly 12. Since both the third encoder 24 and the first encoder 22 are axially opposed, the data measured by the third encoder 24 and the first encoder 22 can be mutually verified, thereby improving the testing accuracy of the frameless motor's operating parameters. Furthermore, the second encoder 23 can also calibrate the third encoder 24.

[0040] In some alternative embodiments, please continue to refer to Figure 3 and Figure 4 To read the test data of the first encoder 22 and the third encoder 24, a circuit board 25 may be included. The circuit board 25 is located between the first encoder 22 and the third encoder 24, and is fixedly connected to the housing assembly 11. In this embodiment, the circuit board 25 is positioned between the first encoder 22 and the third encoder 24, which means that the test data of both encoders can be read simultaneously using a single circuit board 25, achieving test multiplexing for both encoders. Furthermore, since the circuit board 25 is positioned between the first encoder 22 and the third encoder 24, it is equivalent to placing the first encoder 22 and the third encoder 24 on the same side of the circuit board 25. This allows the first encoder 22 and the third encoder 24 to use the same specification of code disk encoders without requiring encoder position avoidance, thus improving the practicality of the test fixture.

[0041] In some alternative embodiments, please continue to refer to Figure 3 To facilitate observation of the testing process and for convenient assembly and wiring, the mounting cover 21 may have several openwork structures 26, through which the first encoder 22, the third encoder 24, and the circuit board 25 are exposed. In this embodiment, the first encoder 22, the third encoder 24, and the circuit board 25 are disposed within the coverage area of ​​the mounting cover 21. By setting the mounting cover 21 as an openwork structure 26, on the one hand, operators can directly observe the internal operating status of the mounting cover 21 from the outside; on the other hand, operators can perform simple operations on the internal components without disassembling the mounting cover 21, such as adjusting the spacing between the first encoder 22, the third encoder 24, and the circuit board 25, and performing wiring operations on the components, etc.

[0042] In some alternative embodiments, please continue to refer to Figure 3 To form the perforated structure 26, the mounting cover 21 may include multiple support columns 27. These support columns 27 extend radially and are fixedly connected, with the gaps between them forming the perforated structure 26. The minimum number of support columns 27 is three, with adjacent support columns forming a 120° angle; alternatively, there may be four support columns 27, with adjacent support columns forming a 90° angle. The gaps between adjacent support columns form the perforated structure 26 on the mounting cover 21, facilitating operator observation of the internal operation or allowing operators to pass through the perforated structure 26 to directly manipulate the components inside the mounting cover 21. To ensure the strength of the mounting cover 21, the support columns 27 can be integrally molded.

[0043] The first encoder 22, second encoder 23, and third encoder 24 in this embodiment can be different types of encoders; for example, the first encoder 22 and third encoder 24, which are fixedly connected to the shaft assembly 12, can be code disk encoders, while the second encoder 23, which is disposed on the mounting cover 21, can be a photoelectric encoder. Photoelectric encoders have higher testing accuracy and can be used to correct the testing accuracy of code disk encoders in addition to detecting the operating data of the frameless motor. The second encoder 23 can be axially fixedly disposed on the outside of the mounting cover 21, which means that the second encoder 23, the first encoder 22, and the third encoder 24 are all located on the rotation axis of the shaft assembly 12. In some optional embodiments, the first encoder 22 includes a code disk encoder, and the second encoder 23 includes a photoelectric encoder.

[0044] In some alternative embodiments, please refer to Figure 5In order to fix the rotor 32 of the frameless motor in order for the shaft assembly 12 to be able to fix the rotor 32, the shaft assembly 12 may specifically include a shaft 121 and a baffle 122. The shaft 121 has a flange 123 on one side in the axial direction. The flange 123 is distributed circumferentially along the shaft 121 and protrudes outward in the radial direction. The baffle 122 and the flange 123 are arranged opposite to each other in the axial direction, and the baffle 122 is detachably connected to the shaft 121. The flange 123 and the baffle 122 cooperate with each other to clamp and fix the rotor 32. The flange 123 formed on the shaft 121 forms a circumferentially distributed receiving groove between itself and the baffle 122. This receiving groove can be used to accommodate the rotor 32 of the frameless motor. The flange 123 and the baffle 122 abut and fix the rotor 32 from both ends, which is equivalent to clamping the rotor 32, thus forming a fixed connection between the rotor 32 and the shaft assembly 12. Moreover, the shaft assembly 12 fixes the rotor 32 by clamping, which also makes it easy to disassemble the rotor 32 after testing without damaging it.

[0045] In some alternative embodiments, please refer to Figure 6 To facilitate assembly and disassembly, particularly for the frameless motor to be installed within the accommodating cavity formed by the housing assembly 11, the housing assembly 11 specifically includes a detachably connected housing body 111, a front cover 112, and a rear cover 113, which together form the accommodating cavity. The shaft assembly 12 has a first connecting portion 124 and a second connecting portion 125 extending axially, which are rotatably connected to the front cover 112 and the rear cover 113, respectively. The housing assembly 11 can be formed by splicing together multiple separable parts, which can be detachably connected by threaded fasteners 14 or other connectors. When the front cover 112 and / or the rear cover 113 are removed, the frameless motor can be placed within the space formed by the housing body 111, which is equivalent to the housing body 111 being fitted outside the stator 31, while the shaft assembly 12 passes through the rotor 32. Then, the front cover 112 and the rear cover 113 can be fixedly connected to the shell body 111, so that the entire test fixture, together with the frameless motor that has been assembled, forms a whole.

[0046] Please continue to refer to this. Figure 6 To allow the pivot assembly 12 to be rotatably connected to the housing assembly 11, the pivot assembly 12 has a first connecting portion 124 and a second connecting portion 125 at both ends. The first connecting portion 124 and the second connecting portion 125 are respectively rotatably connected to the front cover 112 and the rear cover 113. Specifically, the first connecting portion 124 and the front cover 112, and the second connecting portion 125 and the rear cover 113 are rotatably connected by rolling bearings.

[0047] In some alternative embodiments, to securely connect the stator 31 to the housing assembly 11, the housing body 111 is provided with at least one mounting hole 13 communicating with the receiving chamber, and a fastener 14 movably connected to the mounting hole 13; the fastener 14 extends radially into the receiving chamber and is used to abut against and fix the stator 31 to the outer wall. Specifically, the mounting hole 13 and the fastener 14 can be mutually mating screw holes and studs. Multiple mounting holes 13 can be provided along the outer periphery of the housing body 111, with each mounting hole 13 equally spaced, and each mounting hole 13 corresponds to one fastener 14. The fastener 14, by being fixed in the mounting hole 13, has one end extending into the receiving chamber, and can contact the stator 31 of the frameless motor already located in the receiving chamber. By abutting against the stator 31, the stator 31 and the housing body 111 can be fixed together. After testing is completed, the frameless motor can be removed from the receiving chamber simply by contacting the connection between the fastener 14 and the mounting hole 13.

[0048] Fastener 14 can also be a pin, which is inserted into the mounting hole 13 to form an interference fit with the mounting hole 13. One end of the pin located in the receiving cavity abuts against the stator 31, thereby making the stator 31 fixedly connected to the housing assembly 11.

[0049] In order to achieve relative fixation between the stator 31 and the housing assembly 11 when the fastener 14 is abutting against the stator 31, a groove can be provided on the outer periphery of the stator 31 corresponding to the position of the fastener 14. By inserting the end of the fastener 14 into the groove, the movement between the fastener 14 and the stator 31 is limited, thereby achieving a fixed connection between the stator 31 and the housing assembly 11.

[0050] According to the frameless motor test fixture in the embodiments of this application, since the testing mechanism 2 is equipped with two encoders, a first encoder 22 and a second encoder 23, the accuracy of the test fixture can be improved. Moreover, the encoders can also detect and calibrate each other, thereby improving the test accuracy of the encoders in this application and thus improving the product yield of the frameless motor.

[0051] The above examples illustrate this application only to aid understanding and are not intended to limit its scope. Those skilled in the art to which this application pertains can make various simple deductions, modifications, or substitutions based on the ideas presented.

Claims

1. A frameless motor testing fixture, wherein the frameless motor comprises a stator and a rotor nested together; characterized in that, The test fixture includes: The mounting mechanism includes a housing assembly and a rotating shaft assembly; the housing assembly has a receiving chamber, the rotating shaft assembly is disposed through the receiving chamber and is rotatably connected to the housing assembly, and the rotating shaft assembly is used for mounting the stator and rotor of the frameless motor thereon; The detection mechanism includes a mounting cover, a first encoder, and a second encoder. The mounting cover is disposed opposite to the housing assembly along the axial direction of the rotating shaft assembly. The first encoder is located inside the mounting cover and fixedly disposed on the rotating shaft assembly, and is used to detect the operating data of the stator and rotor. The second encoder is fixedly disposed on the mounting cover and is used to receive feedback data from the frameless motor.

2. The frameless motor testing fixture as described in claim 1, characterized in that, It also includes a third encoder, which is disposed opposite to the first encoder along the axial direction. The third encoder is located inside the mounting cover and is fixedly disposed on the rotating shaft assembly.

3. The frameless motor testing fixture as described in claim 2, characterized in that, It also includes a circuit board located between the first encoder and the third encoder, and the circuit board is fixedly connected to the housing assembly.

4. The frameless motor testing fixture as described in claim 3, characterized in that, The mounting cover has a hollow structure.

5. The frameless motor testing fixture as described in claim 4, characterized in that, The mounting cover includes multiple support columns that extend radially and are fixedly connected, with the gaps between the support columns forming the hollow structure.

6. The frameless motor testing fixture as described in claim 1, characterized in that, The second encoder is fixedly disposed on the outside of the mounting cover along the axial direction.

7. The frameless motor testing fixture as described in claim 1, characterized in that, The first encoder includes a code disk encoder, and the second encoder includes an optical encoder.

8. The frameless motor testing fixture as described in any one of claims 1-7, characterized in that, The rotating shaft assembly includes a rotating shaft and a baffle. The rotating shaft has a flange on one side along the axial direction. The flange is distributed circumferentially along the rotating shaft and protrudes radially outward. The baffle is arranged opposite to the flange along the axial direction, and the baffle is detachably connected to the rotating shaft. The flange and the baffle cooperate with each other to clamp and fix the rotor.

9. The frameless motor testing fixture as described in any one of claims 1-7, characterized in that, The housing assembly includes a detachably connected housing body, a front cover, and a rear cover, which together form the receiving chamber; the rotating shaft assembly has a first connecting portion and a second connecting portion extending axially, which are rotatably connected to the front cover and the rear cover, respectively.

10. The frameless motor testing fixture as described in claim 9, characterized in that, The shell body is provided with at least one assembly hole communicating with the receiving chamber, and a fastener movably connected to the assembly hole; the fastener extends radially into the receiving chamber and is used to abut and fix against the outer wall of the stator.

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