Fixture for concentrically assembling flexible gear and cross bearing of harmonic speed reducer

Abstract

The utility model discloses a clamp for concentrically assembling a flexible gear and a cross bearing of a harmonic speed reducer, which comprises a positioning and clamping device comprising an annular base, a diaphragm cavity and a workpiece positioning cavity which are coaxially arranged in the annular base, an elastic diaphragm arranged in the diaphragm cavity, and an air passage communicated with a compressed air source, the elastic membrane can generate radial deformation under the action of air pressure; the ejection device comprises a fixed seat, at least three ejection pins evenly distributed in the circumferential direction of the fixed seat, pin columns connected with the ejection pins and reset springs arranged on the outer sides of the pin columns in a sleeving mode, and the fixed seat is fixedly connected with the annular base; the side wall of the annular base is provided with an ejection air channel communicated with the ejection device, and the outlet end of the ejection air channel is in pneumatic fit with the bottom of the ejection pin. The fixture provided by the utility model has the advantages of high assembly precision, high efficiency, simple structure, convenience in operation and the like, and can be widely applied to the field of concentric assembly of the flexible gear and the cross bearing of the harmonic speed reducer.

Description

Technical Field

[0001] This utility model relates to the field of harmonic reducer assembly technology, specifically to a fixture for concentric assembly of the flexure and cross bearing of a harmonic reducer. Background Technology

[0002] Harmonic reducers are widely used in industrial robots, aerospace, precision machine tools, and other fields, where extremely high transmission accuracy is required. The flexspline and crossed bearings of a harmonic reducer are key components, and their assembly accuracy directly affects the reducer's transmission accuracy, backlash, and smoothness of motion.

[0003] In the field of industrial robotics, high-precision transmission from harmonic reducers is required for precise positioning of end effectors. This necessitates high concentricity and low runout in the assembly of the flexspline and cross bearings to ensure the accuracy and repeatability of the robot's movements. However, existing assembly methods struggle to meet this requirement, resulting in poor concentricity control of the flexspline and cross bearings, leading to lower reducer transmission accuracy and impacting the robot's positioning precision.

[0004] Patent CN207358500U discloses a tooling for improving the assembly accuracy of a flexible wheel and a cross bearing. This tooling achieves precise assembly of the rigid wheel and flexible wheel by designing the matching accuracy of the guide sleeve with the cross bearing, the guide sleeve with the rigid wheel, the guide sleeve with the upper pressure head, the upper pressure head with the rigid wheel, and the lower pad with the input shaft. However, this tooling has a complex structure and is inconvenient to operate. Utility Model Content

[0005] In view of the problems of low assembly accuracy, poor concentricity control, and low assembly efficiency of the flexure and cross bearing in the existing technology, this utility model provides a concentric assembly fixture for the flexure and cross bearing of a harmonic reducer to effectively improve assembly accuracy and efficiency.

[0006] To achieve the above objectives, the embodiments of this utility model adopt the following technical solutions:

[0007] A fixture for concentric assembly of a flexspline and a crossed bearing in a harmonic reducer, comprising:

[0008] The positioning and clamping device includes an annular base, a diaphragm cavity and a workpiece positioning cavity coaxially disposed inside the annular base, an elastic diaphragm disposed inside the diaphragm cavity, and an air passage connected to a compressed air source. The elastic diaphragm can undergo radial deformation under air pressure.

[0009] The ejection device includes a fixed base, at least three ejector pins evenly distributed around the circumference of the fixed base, pins connecting the ejector pins, and a return spring sleeved on the outside of the pins. The fixed base is fixedly connected to the annular base.

[0010] The annular base has an exhaust duct on its side wall that connects to the ejector device, and the outlet end of the exhaust duct is pneumatically fitted with the bottom of the ejector pin.

[0011] In one embodiment, the pin has a columnar structure, and the top end face of the pin has an arc-shaped contact surface that matches the bottom contour of the workpiece to be assembled.

[0012] In one embodiment, the fixing seat and the annular base are coaxially arranged.

[0013] In one embodiment, the inner diameter of the diaphragm cavity is set to the outer diameter of the workpiece to be assembled plus a gap of 0.1 mm to 0.5 mm.

[0014] In one embodiment, the fixing base is provided with a guide hole that slides with the top pin, and the top pin is placed in the guide hole.

[0015] In one embodiment, the ejector air passage includes an axially extending main air passage and a radially branched air passage, the outlet of which forms a pneumatic thrust surface opposite the bottom end face of the ejector pin.

[0016] The beneficial effects of this utility model are that it provides a fixture for the concentric assembly of the flexure and crossed bearing of a harmonic reducer. Through a positioning clamping device and an ejector device, it achieves high-precision concentric assembly of the flexure and crossed bearing. The concentricity of the two parts after assembly can be guaranteed to be no more than 0.005 mm, effectively improving assembly accuracy. The elastic diaphragm structure is simple and easy to operate, avoiding the problem of complex tooling structures in existing technologies. The ejector device adopts a design of top pin, column pin, and return spring, which is easy to operate and further improves assembly efficiency. This utility model device has a compact structure and simple operation, and can be widely used in the concentric assembly of the flexure and crossed bearing of harmonic reducers, meeting the requirements of high-precision transmission in fields such as industrial robots and aerospace. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the clamp described in this utility model;

[0019] Figure 2 This is a schematic diagram of the working state of the fixture described in this utility model.

[0020] The attached figures are labeled as follows: 1. Annular base; 2. Diaphragm cavity; 21. Workpiece positioning cavity; 3. Elastic diaphragm; 4. Air passage; 5. Fixed seat; 6. Top pin; 7. Pillar pin; 8. Return spring; 9. Ejection air passage; 91. Main air passage; 92. Radial branch air passage; 10. Guide hole; 11. Flexible wheel; 12. Cross bearing. Detailed Implementation

[0021] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" 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.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] like Figure 1 , Figure 2 As shown, a concentric assembly fixture for a harmonic reducer flexure and a cross bearing includes a positioning and clamping device and an ejection device. The positioning and clamping device includes an annular base 1, a diaphragm cavity 2 and a workpiece positioning cavity 21 coaxially disposed inside the annular base 1, an elastic diaphragm 3 disposed within the diaphragm cavity 2, and an air passage 4 connecting to a compressed air source. The elastic diaphragm 3 is made of an elastic material, such as silicone or rubber. The elastic diaphragm 3 can undergo radial deformation under air pressure to clamp or release the workpiece. When compressed air generated by the compressed air source enters the diaphragm cavity 2 through the air passage 4, the elastic diaphragm 3 deforms under air pressure, clamping the flexure 11 and the cross bearing 12 inward, thus achieving their positioning within the annular base 1.

[0025] The ejection device includes a fixed base 5, at least three ejector pins 6 evenly distributed around the fixed base 5, pins connecting the ejector pins 6, and a return spring 8 sleeved on the outside of the pins. In this embodiment, three ejector pins 6 are provided to ensure uniform force when the workpiece to be assembled is ejected. The side wall of the annular base 1 is also provided with an ejection air passage 9 that connects to the ejection device. The ejection air passage 9 includes an axially extending main air passage 91 and a radial branch air passage 92. The outlet of the radial branch air passage 92 forms a pneumatic pushing surface opposite the bottom end face of the ejector pin 6 to achieve pneumatic cooperation with the ejector pin 6. The main air passage 91 is an external air source inlet. Compressed air is supplied to the main air passage 91 through an external air source. The compressed air acts on the ejector pin 6 through the radial branch air passage 92. The ejector pin 6 pushes the pin 7 to move axially, ejecting the assembled flexible wheel 11 and cross bearing 12 from the annular base 1. After the supply of compressed air stops, the return spring 8 returns the pin 7 and ejector pin 6 to their original positions.

[0026] The fixed base 5 is coaxially arranged with the annular base 1 to ensure the coaxiality and assembly accuracy of the entire fixture. The fixed base 5 is also provided with a guide hole 10 that slides with the top pin 6. The top pin 6 is placed in the guide hole 10 to ensure the linear movement and stability of the top pin 6 during the ejection process.

[0027] The pin 7 has a columnar structure, and its top end face has an arc-shaped contact surface that matches the bottom contour of the workpiece to be assembled, so as to ensure stability and accuracy during the ejection process.

[0028] The inner diameter of the diaphragm cavity 2 can be set to the outer diameter of the workpiece to be assembled plus a gap of 0.1mm to 0.5mm to ensure that the elastic diaphragm 3 can tightly clamp the flexible wheel 11 and the cross bearing 12, while avoiding excessive clamping that could cause workpiece deformation.

[0029] The working principle of this utility model is as follows: In use, the flexible wheel 11 and the crossed bearing 12 to be assembled are first placed sequentially into the workpiece positioning cavity 21. Compressed air is supplied to the air passage 4 in the diaphragm cavity 2 through an external air source. Under the action of air pressure, the elastic diaphragm 3 undergoes radial deformation, clamping and positioning the outer circles of the flexible wheel 11 and the crossed bearing 12. Then, the connecting bolts between the flexible wheel 11 and the crossed bearing 12 are tightened to achieve concentric assembly. Next, compressed air is supplied to the ejection air passage 9 through an external air source. Under the action of air pressure, the ejector pin 6 moves axially, pushing the assembled flexible wheel 11 and the crossed bearing 12 out of the workpiece positioning cavity 21. After the compressed air supply stops, the return spring 8 returns the ejector pin 6 and the pin post to their original positions, completing the concentric assembly process.

[0030] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the scope of this utility model patent.

[0031] To facilitate understanding by those skilled in the art of the improvements of this utility model over the prior art, some of the drawings and descriptions of this utility model have been simplified, and for clarity, some other elements have been omitted from this application. Those skilled in the art should realize that these omitted elements may also constitute the content of this utility model.

Claims

1. A fixture for concentric assembly of a flexspline and cross bearing of a harmonic reducer, characterized by, The utility model relates to a kind of positioning and clamping device and ejector device, including: Positioning and clamping device, including annular base (1), diaphragm cavity (2) and workpiece positioning cavity (21) being coaxially arranged inside annular base (1), elastic diaphragm (3) being arranged in diaphragm cavity (2) and gas passage (4) being communicated with compressed gas source, the elastic diaphragm (3) can be radially deformed under gas pressure; Ejector device, including fixed seat (5), at least three ejector pins (6) being evenly distributed along the circumference of fixed seat (5), pin post being connected with ejector pin (6) and reset spring (8) being sleeved outside post pin, the fixed seat (5) is fixedly connected with annular base (1); The side wall of the annular base (1) is provided with an ejection gas passage (9) communicating with the ejector device, and the outlet end of the ejection gas passage (9) forms a pneumatic cooperation with the bottom of the ejector pin (6).

2. The fixture for concentric assembly of flexspline and cross bearing of a harmonic reducer of claim 1, wherein, The post pin (7) is in a columnar structure, and the top end surface of the post pin (7) is provided with an arc-shaped contact surface matching the bottom profile of the workpiece to be assembled.

3. The fixture for concentric assembly of flexspline and cross bearing of a harmonic reducer of claim 1, wherein, The fixed seat (5) is coaxially arranged with the annular base (1).

4. The fixture for concentric assembly of flexspline and cross bearing of a harmonic reducer of claim 1, wherein, The inner diameter of the diaphragm cavity (2) is set to the outer diameter of the workpiece to be assembled plus a gap of 0.1mm-0.5mm.

5. The fixture for concentric assembly of flexspline and cross bearing of a harmonic reducer of claim 1, wherein, The fixed seat (5) is provided with a guide hole (10) slidingly cooperating with the ejector pin (6), and the ejector pin (6) is arranged in the guide hole (10).

6. The fixture for concentric assembly of flexspline and cross bearing of a harmonic reducer of claim 1, wherein, The ejection gas passage (9) includes an axially extending main gas passage (91) and a radially branched gas passage (92), and the outlet of the radially branched gas passage (92) is opposite to the bottom end surface of the ejector pin (6) to form a pneumatic thrust surface.

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