Self-adaptive positioning tool and method for thin-wall spray pipe

Abstract

The self-adaptive positioning tool comprises a model tire, a positioning sleeve, a mandrel and the like, the appearance size of the model tire is consistent with the size of the inner profile of the thin-wall spray pipe, the model tire is wrapped on the positioning sleeve through a spring, the positioning sleeve is fixed to the mandrel through a set screw, one side of the positioning sleeve abuts against the thin-wall spray pipe through a check ring and a compression nut, and the other side of the positioning sleeve abuts against the thin-wall spray pipe. As the inner side of the model tire is provided with a curved surface, the model tire is expanded through the circular truncated cone of the positioning sleeve by adjusting the relative position of the model tire and the positioning sleeve, so that the model tire and the inner molded surface of the thin-wall spray pipe are expanded, and supporting can be completed. According to the tool, a complex connecting rod mechanism is omitted, expansion of the model tire is completed through the curved surface effect, the structure is simpler, meanwhile, workpiece clamping operation is easy, reliable clamping of the thin-wall spray pipe can be rapidly achieved, the machining precision of products is guaranteed, and the machining efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of thin-walled nozzle processing technology, and in particular to an adaptive positioning fixture and method for thin-walled nozzles. Background Technology

[0002] Thin-walled nozzles are a typical structural component of aerospace engines and are an essential part of them. However, due to their small wall thickness, curved profile, and poor rigidity, thin-walled nozzles have datum and profile errors after stamping. Direct machining with a machining center will cause workpiece deformation, making it impossible to guarantee design requirements. Existing support fixtures are, on the one hand, specialized and unique, with non-adjustable dimensions. Once the workpiece dimensions are slightly different, they cannot be used. On the other hand, clamping forces can easily cause clamping deformation, resulting in uneven wall thickness and other problems, causing the product's accuracy and surface roughness to fail to meet design requirements. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide an adaptive positioning fixture and method for thin-walled nozzles, which solves the problems of insufficient product precision and surface roughness and uneven wall thickness in the precision machining of thin-walled nozzles, while also making the fixture more versatile, saving fixture costs and improving processing efficiency.

[0004] The technical solution of the present invention is: an adaptive positioning fixture for a thin-walled nozzle, comprising a mandrel, a model kit, and a positioning sleeve;

[0005] The positioning sleeve is fixedly fitted onto the mandrel, and the model tire is wrapped around the positioning sleeve. The model tire can slide relative to the positioning sleeve. The outer shape of the model tire is consistent with the inner surface of the thin-walled nozzle to be processed. The inner side of the model tire has a gradually converging curved wall surface. One end of the positioning sleeve has a protrusion. The root of the protrusion contacts the curved wall surface of the model tire. When the model tire and the positioning sleeve slide relative to each other, the protrusion acts on the curved wall surface, causing the positioning sleeve to evenly expand the model tire in all directions to tighten the thin-walled nozzle.

[0006] Furthermore, the model tire has circumferential grooves, and elastic components are installed in the grooves to wrap the model tire around the positioning sleeve.

[0007] Furthermore, the protrusion is frustum-shaped.

[0008] Furthermore, the mandrel and positioning sleeve are circumferentially positioned by a key, and axially positioned by a set screw.

[0009] Furthermore, one end of the model tire is axially clamped by a positioning nut, and the other end is axially clamped by a retaining ring and a clamping nut.

[0010] Furthermore, the positioning nut and the mandrel are connected by threads; a scale is provided next to the threads of the mandrel and the positioning nut to reflect the degree of expansion of the model tire.

[0011] Furthermore, axial positioning is achieved between the positioning nut and the positioning sleeve through a set screw.

[0012] Furthermore, the retaining ring is installed between the model tire and the clamping nut. The clamping nut and the mandrel are connected by threads. By tightening the clamping nut, the model tire and the positioning sleeve are pushed to move relative to each other, thereby opening the model tire.

[0013] Furthermore, the model tire material is copper.

[0014] This invention also relates to an adaptive positioning method for a thin-walled nozzle, employing the aforementioned adaptive positioning fixture for the thin-walled nozzle, comprising the following steps:

[0015] Place the positioning sleeve on the mandrel and fix it in place. Wrap the model tire around the positioning sleeve so that the maximum point of the curved wall inside the model tire contacts the root of the protrusion of the positioning sleeve.

[0016] Remove the thin-walled nozzle from the model tire;

[0017] Install a retaining ring and a clamping nut on the small end side of the model tire. During the tightening of the clamping nut, push the thin-walled nozzle and the model tire to move relative to the positioning sleeve, thereby opening the model tire and making the model tire and the inner surface of the thin-walled nozzle expand tightly. After the support is completed, fix the positioning nut on the other side of the model tire and fix the positioning sleeve.

[0018] After the thin-walled nozzle is machined, loosen the positioning nut and the clamping nut, remove the retaining ring, and take off the machined thin-walled nozzle.

[0019] The advantages of this invention compared to the prior art are:

[0020] (1) This invention innovatively proposes an adjustable model kit for thin-walled nozzles, which adjusts the degree of expansion to make the model kit and the inner surface of the thin-walled nozzle tightly expand, eliminate the fitting gap, ensure the uniformity of the wall thickness of the thin-walled nozzle, increase the clamping contact area, and reduce the clamping deformation caused by clamping force; at the same time, only one tooling is needed for alignment to meet the processing of thin-walled nozzles with the same inner surface, which has a certain degree of versatility and greatly saves tooling costs;

[0021] (2) This invention relies on the automatic centering of the arc of the model tire and the arc of the part. The adjustment process is simple and does not require special operating skills from the workers. It improves the clamping speed, increases the processing efficiency, and reduces the workload of the workers.

[0022] (4) The present invention adopts a modular design, which can achieve the clamping of various thin-walled nozzles by simply changing different model tires. Furthermore, the modular design allows for the replacement of only worn parts, reducing maintenance costs. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the adaptive positioning tooling clamping method proposed in this invention;

[0024] Figure 2 This is an exploded view of the adaptive positioning fixture proposed in this invention.

[0025] Among them, 1-positioning nut, 2-set screw, 3-spring, 4-mandrel, 5-model tire, 6-set screw, 7-positioning sleeve, 8-retaining ring, 9-compression nut, 10-thin-wall nozzle. Detailed Implementation

[0026] To better understand the technical solution of the present invention, the specific embodiments of the present invention are described below.

[0027] like Figure 1 and Figure 2 As shown, the adaptive positioning fixture provided in this embodiment includes a positioning nut 1, a spring 3, a mandrel 4, a model tire 5, a positioning sleeve 7, a retaining ring 8, and a clamping nut 9. The model tire 5 is fitted onto the mandrel, and the positioning sleeve 7 is wrapped around the model tire 5 by the anti-detachment spring 3. The model tire 5 can slide relative to the positioning sleeve 7, and the positioning nut 1, the retaining ring 8, and the clamping nut 9 are used to clamp the model tire 5 axially.

[0028] The model kit 5 is made of copper, and its external dimensions are consistent with the internal dimensions of the thin-walled nozzle workpiece 10. It is cut into four uniform lobes by wire cutting, and the inner side of the model kit 5 has a curved surface. One end of the positioning sleeve 7 has a frustum, and the root of the frustum of the positioning sleeve 7 contacts the inner curved surface of the model kit 5. When the model kit 5 moves to the left, the frustum of the positioning sleeve 7 opens up the model kit 5.

[0029] The positioning nut 1 and the mandrel 4 are connected by threads. There is a scale next to the threads of the mandrel 4 and the positioning nut 1, which can directly reflect the degree of expansion of the model tire and facilitate adjustment. The mandrel 4 and the positioning sleeve 7 are circumferentially positioned by a key and axially positioned by a set screw 6. The positioning nut 1 and the positioning sleeve 7 are axially positioned by a set screw 2. The mandrel 4 and the clamping nut 9 are connected by threads.

[0030] When in use, place the positioning sleeve 7 on the middle part of the mandrel 4, tighten the set screw 6 to fix it, and use the spring 3 to wrap the model kit 5 around the positioning sleeve 7. The maximum point of the inner curved surface of the model kit 5 is in contact with the bottom surface of the frustum of the positioning sleeve 7.

[0031] Place the thin-walled nozzle workpiece 10 onto the model kit 5 from the right end, then install the retaining ring 8 and the clamping nut 9. During the tightening of the clamping nut 9, push the thin-walled nozzle workpiece 10 and the model kit 5 to move to the left relative to the positioning sleeve 7, thereby opening the model kit 5. As a result, the model kit 5 and the inner surface of the thin-walled nozzle workpiece 10 are tightened, thus completing the support. Then, fix the positioning nut 1 and the positioning sleeve 7 with the set screw 2.

[0032] The left end positioning nut 1 is hexagonal, and the other end is cantilevered. Then, the shape of the thin-walled nozzle workpiece 10 is precision machined. After the machining is completed, the left end positioning nut 1 and the right end clamping nut 9 are loosened and the retaining ring is removed to take off the precision machined workpiece.

[0033] It is understood that this invention has been described through embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific circumstances without departing from the spirit and scope of this invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are protected by this invention.

[0034] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. An adaptive positioning fixture for a thin-walled nozzle, characterized in that: Includes a mandrel (4), a model tire (5), and a positioning sleeve (7); The positioning sleeve (7) is fixedly sleeved on the mandrel (4), and the model tire (5) is wrapped around the positioning sleeve (7). The model tire (5) can slide relative to the positioning sleeve (7). The outer shape of the model tire (5) is consistent with the inner surface of the thin-walled nozzle to be processed. The inner side of the model tire (5) has a gradually converging curved wall surface. One end of the positioning sleeve (7) has a protrusion. The root of the protrusion contacts the curved wall surface of the model tire (5). When the model tire (5) and the positioning sleeve (7) slide relative to each other, the protrusion acts on the curved wall surface, so that the positioning sleeve (7) evenly expands the model tire (5) in all directions to tighten the thin-walled nozzle.

2. The adaptive positioning fixture for thin-walled nozzles according to claim 1, characterized in that: The model tire (5) has a circumferential groove, and an elastic component is installed in the groove. The model tire (5) is wrapped around the positioning sleeve (7) by the elastic component.

3. The adaptive positioning fixture for a thin-walled nozzle according to claim 1, characterized in that: The protrusion is frustum-shaped.

4. The adaptive positioning fixture for a thin-walled nozzle according to claim 1, characterized in that: The spindle (4) and the positioning sleeve (7) are circumferentially positioned by a key and axially positioned by a set screw (6).

5. The adaptive positioning fixture for a thin-walled nozzle according to claim 1, characterized in that: The model tire (5) is axially clamped at one end by a positioning nut (1) and at the other end by a retaining ring (8) and a clamping nut (9).

6. The adaptive positioning fixture for a thin-walled nozzle according to claim 5, characterized in that: The positioning nut (1) and the mandrel (4) are connected by threads; a scale is provided next to the threads of the mandrel and the positioning nut (1) to reflect the degree of expansion of the model tire (5).

7. The adaptive positioning fixture for a thin-walled nozzle according to claim 5, characterized in that: Axial positioning is achieved between the positioning nut (1) and the positioning sleeve (7) by the set screw (2).

8. The adaptive positioning fixture for a thin-walled nozzle according to claim 5, characterized in that: The retaining ring (8) is installed between the model tire (5) and the clamping nut (9). The clamping nut (9) and the spindle (4) are connected by threads. By tightening the clamping nut (9), the model tire (5) and the positioning sleeve (7) are pushed to move relative to each other, thereby opening the model tire (5).

9. The adaptive positioning fixture for a thin-walled nozzle according to claim 1, characterized in that: The model tire (5) is made of copper.

10. An adaptive positioning method for a thin-walled nozzle, characterized in that: The adaptive positioning fixture for the thin-walled nozzle as described in claim 1 includes the following steps: Place the positioning sleeve (7) on the mandrel (4) and fix it in place. Wrap the model tire (5) around the positioning sleeve (7) so that the maximum part of the curved wall inside the model tire (5) contacts the root of the protrusion of the positioning sleeve (7). Remove the thin-walled nozzle (10) from the mold (5); Install a retaining ring (8) and a clamping nut (9) on the small end side of the model tire (5). During the tightening of the clamping nut (9), push the thin-walled nozzle (10) and the model tire (5) to move relative to the positioning sleeve (7), thereby opening the model tire (5) and making the model tire (5) and the inner surface of the thin-walled nozzle (10) expand tightly. After the support is completed, fix the positioning nut (1) on the other side of the model tire (5) and fix the positioning sleeve (7). After the thin-walled nozzle (10) is processed, loosen the positioning nut (1) and the clamping nut (9), remove the retaining ring (8), and take off the processed thin-walled nozzle.

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