Hobbing clamp for thin-wall annular harmonic flexible gear

Abstract

The utility model discloses a hobbing clamp of a thin-wall annular harmonic flexible gear. The hobbing clamp comprises a hollow elastic clamp body and an expansion pull rod. The upper end of the hollow elastic clamp body is provided with a positioning outer circle and a positioning face, an inner hole of the positioning outer circle is provided with an inner conical face, a first positioning hole, a middle via hole and a second positioning hole are sequentially formed in the lower face of the inner conical face, and a screw via hole and a positioning pin hole are formed in a lower end connecting flange at the bottom of the hollow elastic clamp body. The upper end of the expansion pull rod is provided with an outer conical surface and a first positioning outer circle, the middle is provided with a second positioning outer circle, and the lower end is provided with external threads. The fixture not only can eliminate the fit clearance between the core rod and the inner hole of the thin-wall circular harmonic flexible gear, but also can accurately control the magnitude of the expansion force as required, and ensures the gear hobbing precision and size consistency of the thin-wall circular harmonic flexible gear, thereby overcoming the defects in the prior art.

Description

Technical Field

[0001] This utility model relates to a hobbing fixture for a thin-walled annular harmonic flexible gear, belonging to the technical field of harmonic gear processing equipment. Background Technology

[0002] Thin-walled annular harmonic flexures are widely used in harmonic reducers. The hobbing accuracy and dimensional consistency of the thin-walled annular harmonic flexure directly affect, and even determine, the transmission accuracy, backlash, and service life of the harmonic reducer.

[0003] For the hobbing of thin-walled annular harmonic flexible gears, the commonly used method in current production is to use the inner hole of the thin-walled annular harmonic flexible gear as a reference, and to use a tapered mandrel or a straight mandrel with a very small clearance for machining. The advantages of this method are convenient product clamping and low tooling manufacturing costs; the disadvantage is that it is difficult to guarantee the accuracy and tooth thickness consistency of the hobbing of the thin-walled annular harmonic flexible gear. This is because the thin-walled annular harmonic flexible gear has a special structure; it is a thin-walled part. Although the tapered mandrel can tighten the inner hole and eliminate the clearance between the mandrel and the inner hole, the tightening force is difficult to control and is inconsistent. On the other hand, a clearance always exists between the straight mandrel and the inner hole. This difference in tightening force and the presence of clearance obviously affect the accuracy and tooth thickness consistency of the hobbing of the thin-walled annular harmonic flexible gear. Summary of the Invention

[0004] The purpose of this invention is to provide a hobbing fixture for a thin-walled annular harmonic flexible wheel. This fixture not only eliminates the fit clearance between the mandrel and the inner hole of the thin-walled annular harmonic flexible wheel, but also accurately controls the magnitude of the tension force as needed, ensuring the hobbing accuracy and dimensional consistency of the thin-walled annular harmonic flexible wheel, thereby overcoming the shortcomings of the prior art.

[0005] The technical solution of this utility model is as follows: A gear hobbing clamp for a thin-walled annular harmonic flexible wheel includes a hollow elastic clamp body and a tensioning rod; the upper end of the hollow elastic clamp body is provided with a positioning outer circle and a positioning surface, the inner hole of the positioning outer circle is provided with an inner conical surface, and the lower part of the inner conical surface is provided with a first positioning hole, a middle through hole and a second positioning hole in sequence; the lower end of the hollow elastic clamp body is provided with a screw through hole and a positioning pin hole on the connecting flange; the upper end of the tensioning rod is provided with an outer conical surface and a first positioning outer circle, the middle part is provided with a second positioning outer circle, and the lower end is provided with an external thread.

[0006] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, the inner conical surface of the hollow elastic fixture body has the same taper as the outer conical surface of the tensioning rod.

[0007] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, the hollow elastic fixture body has a uniformly distributed elastic through groove on its positioning outer circle, and the length of the elastic through groove extends from the end face of the positioning outer circle to the end face of the first positioning hole.

[0008] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, when the thin-walled annular harmonic flexible wheel is fitted into the positioning outer circle and positioning surface of the hollow elastic fixture body but not tightened, there is a gap between the lower end face of the first positioning outer circle of the tightening rod and the lower end face of the first positioning hole of the hollow elastic fixture body.

[0009] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, the size of the first positioning hole of the hollow elastic fixture body is larger than the size of the intermediate through hole, and the size of the intermediate through hole is larger than the size of the second positioning hole.

[0010] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, the axial dimension of the inner conical surface of the hollow elastic fixture body is greater than the axial dimension of its upper positioning outer circle, and the axial dimension of the positioning outer circle is greater than the axial dimension of the thin-walled annular harmonic flexible wheel.

[0011] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, the first positioning hole and the second positioning hole of the hollow elastic fixture body are respectively clearance-fitted with the first positioning outer circle and the second positioning outer circle of the tensioning rod.

[0012] In the aforementioned gear hobbing fixture for a thin-walled annular harmonic flexible wheel, the fitting clearance between the outer positioning circle of the hollow elastic fixture body and the inner hole of the thin-walled annular harmonic flexible wheel is 0.005-0.01 mm.

[0013] The beneficial effects of this utility model are as follows: Due to the adoption of the above-mentioned technical solution, this utility model has the following advantages compared with the straight mandrels and tapered mandrels commonly used in current production:

[0014] 1. The present invention relates to a gear hobbing fixture for a thin-walled annular harmonic flexible wheel, comprising a hollow elastic fixture body and a tensioning rod. The hollow elastic fixture body and the tensioning rod are connected by an inner conical surface and an outer conical surface. The thin-walled annular harmonic flexible wheel to be processed is fitted onto the positioning outer circle and positioning surface outside the inner conical surface of the hollow elastic fixture body. The tensioning rod is tightened by the hydraulic system of the gear hobbing machine to achieve tension. There is no gap between the gear hobbing fixture and the inner hole of the thin-walled annular harmonic flexible wheel, thus eliminating the processing error caused by the gap.

[0015] 2. In the gear hobbing fixture for a thin-walled annular harmonic flexible wheel of this utility model, the axial dimension of the inner conical surface of the hollow elastic fixture body is greater than the axial dimension of its positioning outer circle, the axial dimension of the positioning outer circle is greater than the axial dimension of the thin-walled annular harmonic flexible wheel, the size of the first positioning hole is greater than the size of the intermediate through hole, and when the thin-walled annular harmonic flexible wheel is fitted into the positioning outer circle and positioning surface of the hollow elastic fixture body without being tightened, there is a gap of L mm between the lower end face of the first positioning outer circle of the tightening rod and the lower end face of the first positioning hole of the hollow elastic fixture body. When the tightening rod is tightened by pulling down the tightening rod through the hydraulic system of the gear hobbing machine, the tightening rod can only move a fixed distance of L mm. Therefore, the magnitude of the tightening force on the thin-walled annular harmonic flexible wheel is constant, and there is no problem of difficulty in controlling the magnitude of the tightening force or inconsistency between the upper and lower parts. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model and its cooperation with a thin-walled annular harmonic flexible wheel;

[0017] Figure 2 This is a schematic diagram of the hollow elastic clamp body in this utility model.

[0018] Figure 3 yes Figure 2 Top view.

[0019] Figure 4 This is a schematic diagram of the tensioning rod in this utility model.

[0020] Reference numerals: 1-Hollow elastic clamp body, 2-Tightening rod, 3-Annular harmonic flexible wheel, 1.1-Locking outer circle, 1.2-Locking surface, 1.3-Inner conical surface, 1.4-First positioning hole, 1.5-Intermediate through hole, 1.6-Second positioning hole, 1.7-Elastic groove, 1.8-Screw through hole, 1.9-Locking pin hole, 2.1-Outer conical surface, 2.2-First positioning outer circle, 2.3-Second positioning outer circle, 2.4-External thread, 3-Thin-walled annular harmonic flexible wheel. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0022] An embodiment of this utility model: A gear hobbing clamp for a thin-walled annular harmonic flexible wheel includes a hollow elastic clamp body 1 and a tensioning rod 2; the upper end of the hollow elastic clamp body 1 is provided with a positioning outer circle 1.1 and a positioning surface 1.2, the inner hole of the positioning outer circle 1.1 is provided with an inner conical surface 1.3, and the lower part of the inner conical surface 1.3 is provided with a first positioning hole 1.4, a middle through hole 1.5 and a second positioning hole 1.6 in sequence; the lower end of the hollow elastic clamp body 1 is provided with a screw through hole 1.8 and a positioning pin hole 1.9 on the connecting flange; the upper end of the tensioning rod 2 is provided with an outer conical surface 2.1 and a first positioning outer circle 2.2, the middle part is provided with a second positioning outer circle 2.3, and the lower end is provided with an external thread 2.4.

[0023] During use, the connecting flange at the lower end of the hollow elastic clamp body 1 is fixed to the gear hobbing machine worktable by screws and positioning pins passing through screw holes 1.8 and positioning pin holes 1.9 respectively; the external thread 2.4 at the lower end of the tensioning rod 2 is screwed into the internal thread interface of the gear hobbing machine hydraulic system; the thin-walled annular harmonic flexible wheel 3 to be processed is sleeved on the positioning outer circle 1.1 and positioning surface 1.2 at the upper end of the hollow elastic clamp body 1. The gear hobbing machine hydraulic system pulls the tensioning rod 2 downward, and the outer conical surface 2.1 of the tensioning rod 2 contacts the inner conical surface 1.3. Under the action of extrusion force, the positioning outer circle 1.1 expands outward to achieve the tensioning of the thin-walled annular harmonic flexible wheel 3.

[0024] The inner conical surface 1.3 of the hollow elastic clamp body 1 has the same taper as the outer conical surface 2.1 of the tensioning rod 2. The size of the taper is determined according to the size of the tensioning force required when processing the thin-walled annular harmonic flexible wheel 3.

[0025] The hollow elastic clamp body 1 has a positioning outer circle 1.1 with evenly distributed elastic grooves 1.7 along the circumference. The length of the elastic grooves 1.7 extends from the end face of the positioning outer circle 1.1 to the end face of the first positioning hole 1.4. Under the compression of the tensioning rod 2, the positioning outer circle 1.1 can expand outward, thereby fixing the thin-walled annular harmonic flexible wheel 3 in place. The width and number of elastic grooves 1.7 are determined according to the magnitude of the tensioning force required when processing the thin-walled annular harmonic flexible wheel 3.

[0026] When the thin-walled annular harmonic flexible wheel 3 is fitted into the positioning outer circle 1.1 and positioning surface 1.2 of the hollow elastic clamp body 1 without being tightened, there is a gap of L mm between the lower end face of the first positioning outer circle 2.2 of the tightening rod 2 and the lower end face of the first positioning hole 1.4 of the hollow elastic clamp body 1. The size of the gap is determined according to the magnitude of the tightening force required when processing the thin-walled annular harmonic flexible wheel 3.

[0027] The size of the first positioning hole 1.4 of the hollow elastic clamp body 1 is larger than the size of the intermediate through hole 1.5, and the size of the intermediate through hole 1.5 is larger than the size of the second positioning hole 1.6.

[0028] The axial dimension of the inner conical surface 1.3 of the hollow elastic clamp body 1 is greater than the axial dimension of the upper positioning outer circle 1.1. The axial dimension of the positioning outer circle 1.1 is greater than the axial dimension of the thin-walled annular harmonic flexible wheel 3, ensuring that the thin-walled annular harmonic flexible wheel 3 is fully fitted onto the positioning outer circle 1.1.

[0029] The first positioning hole 1.4 and the second positioning hole 1.6 of the hollow elastic clamp body 1 are respectively fitted with the first positioning outer circle 2.2 and the second positioning outer circle 2.3 of the tensioning rod 2 to facilitate the insertion of the tensioning rod 2.

[0030] The size of the outer positioning circle 1.11 of the hollow elastic clamp body 1 is determined according to the inner hole size of the machined thin-walled annular harmonic flexible wheel 3, and the fit clearance between the two is 0.005-0.01mm, which facilitates the positioning and installation of the thin-walled annular harmonic flexible wheel 3.

[0031] The hobbing fixture of this utility model consists of a hollow elastic fixture body 1 and a tensioning rod 2. The hollow elastic fixture body 1 and the tensioning rod 2 are connected by an inner conical surface 1.3 and an outer conical surface 2.1. The thin-walled annular harmonic flexible wheel 3 to be processed is fitted on the positioning outer circle 1.1 and positioning surface 1.2 outside the inner conical surface 1.3 of the hollow elastic fixture body 1. The positioning surface 1.2 supports the thin-walled annular harmonic flexible wheel 3 to be processed and prevents it from falling. The tensioning rod 2 is tightened by the hydraulic system of the hobbing machine to achieve tension. There is no gap between the hobbing fixture and the inner hole of the thin-walled annular harmonic flexible wheel 3, thus eliminating the processing error caused by the gap.

[0032] Furthermore, in the hobbing fixture of this utility model, the axial dimension of the inner conical surface 1.3 of the hollow elastic fixture body 1 is larger than the axial dimension of its positioning outer circle 1.1, the axial dimension of the positioning outer circle 1.1 is larger than the axial dimension of the thin-walled annular harmonic flexible wheel 3, the size of the first positioning hole 1.4 is larger than the size of the intermediate through hole 1.5, and when the thin-walled annular harmonic flexible wheel 3 is fitted into the positioning outer circle 1.1 and positioning surface 1.2 of the hollow elastic fixture body 1 without being tightened, there is a gap of L mm between the lower end face of the first positioning outer circle 2.2 of the tightening rod 2 and the lower end face of the first positioning hole 1.4 of the hollow elastic fixture body 1. When the tightening rod 2 is tightened by pulling down the hydraulic system of the hobbing machine, the tightening rod 2 can only move a fixed distance of L mm. Therefore, the magnitude of the tightening force on the thin-walled annular harmonic flexible wheel is constant, and there is no problem of difficulty in controlling the magnitude of the tightening force or inconsistency between the upper and lower parts.

Claims

1. A gear hobbing fixture for a thin-walled annular harmonic flexible gear, characterized in that: The device includes a hollow elastic clamp body (1) and a tensioning rod (2); the upper end of the hollow elastic clamp body (1) is provided with a positioning outer circle (1.1) and a positioning surface (1.2), the inner hole of the positioning outer circle (1.1) is provided with an inner conical surface (1.3), and the lower part of the inner conical surface (1.3) is provided with a first positioning hole (1.4), a middle through hole (1.5) and a second positioning hole (1.6) in sequence, and the lower end of the hollow elastic clamp body (1) is provided with a screw through hole (1.8) and a positioning pin hole (1.9) on the connecting flange at the bottom of the hollow elastic clamp body (1); the upper end of the tensioning rod (2) is provided with an outer conical surface (2.1) and a first positioning outer circle (2.2), the middle part is provided with a second positioning outer circle (2.3), and the lower end is provided with an external thread (2.4).

2. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: The inner conical surface (1.3) of the hollow elastic clamp body (1) has the same taper as the outer conical surface (2.1) of the tensioning rod (2).

3. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: The hollow elastic clamp body (1) has an elastic through groove (1.7) evenly distributed along the circumference on the positioning outer circle (1.1). The length of the elastic through groove (1.7) extends from the end face of the positioning outer circle (1.1) to the end face of the first positioning hole (1.4).

4. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: When the thin-walled annular harmonic flexible wheel (3) is fitted into the positioning outer circle (1.1) and positioning surface (1.2) of the hollow elastic clamp body (1) but not tightened, there is a gap between the lower end face of the first positioning outer circle (2.2) of the tightening rod (2) and the lower end face of the first positioning hole (1.4) of the hollow elastic clamp body (1).

5. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: The size of the first positioning hole (1.4) of the hollow elastic clamp body (1) is larger than the size of the intermediate through hole (1.5), and the size of the intermediate through hole (1.5) is larger than the size of the second positioning hole (1.6).

6. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: The axial dimension of the inner conical surface (1.3) of the hollow elastic clamp body (1) is greater than the axial dimension of its upper positioning outer circle (1.1), and the axial dimension of the positioning outer circle (1.1) is greater than the axial dimension of the thin-walled annular harmonic flexible wheel (3).

7. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: The first positioning hole (1.4) and the second positioning hole (1.6) of the hollow elastic clamp body (1) are respectively clearance-fitted with the first positioning outer circle (2.2) and the second positioning outer circle (2.3) of the tensioning rod (2).

8. The gear hobbing fixture for a thin-walled annular harmonic flexible wheel according to claim 1, characterized in that: The fitting clearance between the outer positioning circle (1.1) of the hollow elastic clamp body (1) and the inner hole of the thin-walled annular harmonic flexible wheel (3) is 0.005-0.01mm.

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