Device and method for drilling symmetrical inclined holes in a circular arc surface of a bend

Abstract

This invention discloses a device and method for drilling symmetrical oblique holes on the arc surface of a bent pipe corner. The device includes a base, a pressure plate, a support screw, a screw rod, a nut, and a drill sleeve. The base has two oblique surfaces, which serve as support surfaces for contact with the machine tool when drilling two symmetrical oblique holes. The base also has a positioning surface for contact with the bent pipe and drill sleeve holes. The pressure plate also has drill sleeve holes and is connected to the base plate via a positioning sliding hole, a nut, and a screw rod. The support screw is installed on the base to assist in supporting the bent pipe. One end face of the bent pipe is pressed against the positioning support surface of the base, and then the other end face of the bent pipe is supported by the other support surface or the support screw. Simultaneously, the pressure plate clamps the arc surface of the bent pipe corner, and then the nut and screw rod lock the pressure plate and the base to process the symmetrical oblique holes. This invention can complete the processing of symmetrical oblique holes in a single setup, with high positional accuracy and a simple processing method.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine machining technology, specifically relating to a device and method for drilling symmetrical oblique holes with a pipe bending head. Background Technology

[0002] There is a type of bent tube component in aero engines that requires drilling two symmetrical oblique holes on two arc surfaces at the corner of the bent tube component. It is difficult to achieve the function of drilling two holes at the same time using general drilling methods, especially since it is difficult to guarantee the symmetrical accuracy of the position after drilling.

[0003] Currently, drilling holes in bent pipes typically involves marking points on the curved surface of the pipe, holding it in place, and then drilling with a hand drill. This method results in inaccurate hole placement, is cumbersome, and makes it difficult to guarantee the required tolerances. While there are many existing drilling methods for bent pipes, these methods either easily cause deformation of the bent pipe after drilling, cannot guarantee the positional accuracy of the angled hole, or require the use of high-precision machine tools. Summary of the Invention

[0004] The present invention aims to provide a device and method for drilling symmetrical oblique holes on the arc surface of a bent pipe, which can drill two high-precision symmetrical oblique holes on the two arc surfaces of the bent pipe part, solving the technical problems of the inability of commonly used positioning devices to position accurately and the inconvenience of operation, and has low processing cost and wide application range.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A device for drilling symmetrical oblique holes on the arc surface of a pipe bend includes:

[0007] The base has a surface comprising a first drilling reference plane and a second drilling reference plane that are symmetrical to each other, a first support surface for supporting the first end of the bend and a second support surface for supporting the second end of the bend. The base is also provided with a first drill sleeve and a first through hole. The axis of the first drill sleeve is perpendicular to the first drilling reference plane. Below the first drill sleeve is a first clamping surface for clamping the arc surface of the bend corner. The first through hole has at least one section of internal thread.

[0008] A pressure plate is slidably inserted into the first through hole of the base. The surface of the pressure plate includes a second clamping surface for clamping the arc surface of the bend corner and a second through hole. A second drill sleeve is provided above the second clamping surface. The axis of the second drill sleeve is perpendicular to the second drilling reference plane. There is at least one section of internal thread in the second through hole.

[0009] The screw, nut, and anti-rotation screw are provided. The screw is connected to the internal threads of both the first and second through holes. The nut is connected to one end of the screw. The anti-rotation screw intersects with the screw and the base through a fitting mechanism.

[0010] In the above scheme, a radial clamping force along the cross section at the bend corner and a clamping force relative to the first support surface are formed between the first clamping surface and the second clamping surface.

[0011] As one option, a threaded hole is provided on the first support surface, and a support screw is connected to the threaded hole.

[0012] As one option, the first and second pressing surfaces are arranged symmetrically about the bend.

[0013] A method for drilling symmetrical oblique holes on the arc surface of a bent pipe, including clamping and drilling steps.

[0014] In the clamping step, the same clamp is used to support and tighten the first and second ends of the bend at the same time, and the support and tightening directions are respectively along the axial direction of the first end and the axial direction of the second end of the bend. Then, the arc surface at the corner of the bend is symmetrically clamped to restrict the bend from rotating around the first end or the second end.

[0015] In the drilling step, different surfaces of the fixture from the clamping step are used as positioning references and placed on the platform of the drilling equipment. Without disassembling the fixture, the symmetrical oblique hole processing of the curved pipe corner arc surface is carried out sequentially by switching the positioning references.

[0016] As one approach, the clamping and drilling steps employ the aforementioned device for drilling symmetrical oblique holes on the curved surface of a bent pipe without support screws. The first and second support surfaces simultaneously support and tighten the first and second ends of the bent pipe. The first and second pressing surfaces symmetrically clamp the curved surface at the corner of the bent pipe. The first and second drilling reference planes are used to machine the symmetrical oblique holes on the curved surface of the bent pipe corner, respectively.

[0017] As one approach, the clamping and drilling steps employ the aforementioned device for drilling symmetrical oblique holes on the curved surface of a bent pipe with supporting screws. The head end face of the supporting screw and the second supporting face simultaneously support and tighten the first and second ends of the bent pipe. The first and second pressing surfaces symmetrically clamp the curved surface at the corner of the bent pipe. The first and second drilling reference planes respectively machine the symmetrical oblique holes on the curved surface of the bent pipe corner.

[0018] As one approach, in the clamping step, the clamping force of the first and second clamping surfaces is adjusted by rotating the screw.

[0019] As one approach, during the clamping step, the supporting and tightening force at the first end of the bent pipe is adjusted by rotating the support screw.

[0020] As one option, in the drilling step, a bench drill is used to machine symmetrical inclined holes.

[0021] The drilling device of the present invention has two inclined surfaces on the base, which serve as support surfaces for contact with the machine tool when drilling two symmetrical inclined holes. At the same time, there are positioning surfaces and drill sleeve holes on the base that contact the bent pipe. The pressure plate is connected to the base plate through the positioning sliding hole. When tightened with a nut, it can provide force to clamp the bent pipe. The support screw is used to assist in supporting the bent pipe.

[0022] The method of drilling symmetrical oblique holes is adopted. One end face of the bent pipe is pressed against the positioning support surface of the base. Then, another support surface or support screw is used to assist in supporting the other end face of the bent pipe. At the same time, the corner arc surface of the bent pipe is clamped with a pressure plate. Then, the pressure plate and the base are locked with nuts and screws to complete the clamping before bending pipe processing. Then, the operator places the clamped and positioned bent pipe on the bench drill for drilling.

[0023] Compared with existing methods for machining symmetrical oblique holes on the corners of bent pipes, this invention designs a dedicated machining device as a fixture. Using this fixture for machining symmetrical oblique holes on the corners of bent pipes has the following advantages:

[0024] (1) A fixed base positioning and pressure plate pressing the bend corner arc surface and auxiliary support bend end faces are adopted to ensure the accuracy of positioning dimensions. The bend will not rotate or translate during the oblique hole processing. Since the two ends of the bend only have axial support force, it will not cause deformation of the pipe opening section.

[0025] (2) Two inclined planes are set on the base as the first drilling reference plane and the second drilling reference plane respectively. This can ensure that two inclined holes are processed at the same time after a set of fixtures is clamped at once, avoiding the error introduced by repeated clamping (i.e., only one inclined hole is processed at a time). At the same time, the use of fixed drill bushing and bench drill to cooperate with drilling further ensures the accuracy of precision.

[0026] (3) The device for drilling symmetrical oblique holes on the arc surface of the bend pipe is small and lightweight, convenient for workers to operate, has low processing cost, and the support and clamping force and the clamping force are easy to adjust. It is suitable for drilling holes in bend pipes of different specifications and materials and has a wide range of applications. Attached Figure Description

[0027] Figure 1 This is a structural diagram of the device for drilling symmetrical oblique holes on the arc surface of a bent pipe corner in this invention;

[0028] Figure 2 This is a three-dimensional structural diagram of the base in this invention;

[0029] In the diagram, 1-base; 2-pressure plate; 3-support screw; 4-screw; 5-nut; 6-drill bushing. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, it should not be construed that the scope of the subject matter of the present invention is limited to the following embodiments. All modifications, substitutions and alterations made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention are included within the scope of the present invention.

[0031] like Figures 1-2 As shown, the device for drilling symmetrical oblique holes on the curved surface of a pipe bend includes a base 1, a pressure plate 2, a support screw 3, a screw rod 4, a nut 5, and a drill sleeve 6. Figure 1 and Figure 2 In the middle, the two inclined surfaces at the lower end of the base 1 serve as the first drilling reference plane and the second drilling reference plane, respectively. Figure 1 Reference datums A and B are defined. A protrusion extends below the front end face of base 1, with its upper surface serving as the first support surface and the front end face of base 1 as the second support surface. Above the protrusion is a cantilever structure extending from the front end face of base 1. A drill sleeve 6 is mounted on the cantilever structure, and the surface of the cantilever structure below the drill sleeve 6 forms the first clamping surface. A circular stepped through-hole is also formed on base 1, with the larger portion serving as the sliding insertion area for pressure plate 2, and the smaller portion forming an internal thread section that mates with screw 4. Pressure plate 2 includes a cylindrical structure, a cantilever identical to the cantilever structure on base 1, and a threaded through-hole. The cylindrical structure slides into the circular stepped through-hole on base 1. Another drill sleeve 6 is mounted on the cantilever, and the cantilever surface forms the second clamping surface. Screw 4 passes through the internal thread section of the circular stepped through-hole and the threaded through-hole of pressure plate 2, and is then locked axially by nut 5. After screw 4 is installed on base 1 and pressure plate 2, it is manufactured through a mating method. Figure 1 The anti-rotation screw hole is drilled in the center, and the anti-rotation screw is installed. The anti-rotation screw is screwed into the screw rod 4 and the base 1 to prevent the screw rod 4 from rotating during the drilling of the inclined hole. The support screw 3 is installed on the first support surface, and its distance to the first end of the bend can be adjusted by rotation.

[0032] In the device for drilling symmetrical oblique holes on the arc surface of a bent pipe, firstly, the pressure plate 2 is installed into the circular stepped through hole on the base 1, and then the screw 4 is screwed in. The screw 4 is connected to the base 1 by means of an anti-rotation screw, ensuring that the pressure plate 2 can slide in the circular stepped through hole of the base 1. Next, the support screw 3 is screwed onto the base 1, and the nut 5 is screwed onto the screw 4. In this way, the entire device for drilling symmetrical oblique holes on the arc surface of a bent pipe is assembled.

[0033] During drilling, place the first end face of the bent pipe against the front end face (second support surface) of the base 1, and use the head of the support screw 3 to press the second end face of the bent pipe upwards. Then, clamp it with the pressure plate 2. When the reference surface A or reference surface B is flat on the platform of the bench drill, the required symmetrical inclined holes can be machined respectively. When switching reference surfaces, it is not necessary to disassemble the symmetrical inclined hole drilling device on the curved surface of the bent pipe. After drilling is completed, loosen the pressure plate 2 and the support screw 3, and remove the bent pipe.

[0034] Contents not described in detail in this specification are prior art known to those skilled in the art. Although illustrative specific embodiments of the invention have been described above to facilitate understanding by those skilled in the art, it should be understood that the invention is not limited to the scope of the specific embodiments. Various modifications are readily apparent to those skilled in the art as long as they fall within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of this invention are protected.

Claims

1. A device for drilling symmetrical oblique holes on the arc surface of a bent pipe corner, characterized in that, include: The base (1) has a surface that includes a first drilling reference plane and a second drilling reference plane that are symmetrical to each other, as well as a first support surface for supporting the first end of the bend and a second support surface for supporting the second end of the bend. The base (1) is also provided with a first drill sleeve and a first through hole. The axis of the first drill sleeve is perpendicular to the first drilling reference plane. Below the first drill sleeve is a first clamping surface for clamping the arc surface of the bend corner. The first through hole has at least one section of internal thread. The pressure plate (2) is slidably inserted into the first through hole of the base (1). The surface of the pressure plate (2) includes a second pressing surface for clamping the arc surface of the bend and a second through hole. A second drill sleeve is provided above the second pressing surface. The axis of the second drill sleeve is perpendicular to the second drilling reference plane. There is at least one section of internal thread in the second through hole. The screw (4), nut (5) and anti-rotation screw are connected to the internal threads of the first through hole and the second through hole. The nut (5) is connected to one end of the screw (4). The anti-rotation screw intersects with the screw (4) and the base (1) through a matching mechanism. A threaded hole is provided on the first support surface, and a support screw (3) is connected in the threaded hole. The first and second pressing surfaces are arranged symmetrically about the bend.

2. A method for drilling symmetrical oblique holes on the arc surface of a bent pipe corner, characterized in that: This includes the clamping and drilling steps. In the clamping step, the same clamp is used to support and tighten the first and second ends of the bend at the same time, and the support and tightening directions are respectively along the axial direction of the first end and the axial direction of the second end of the bend. Then, the arc surface at the corner of the bend is symmetrically clamped to restrict the bend from rotating around the first end or the second end. In the drilling step, different surfaces of the fixture in the clamping step are used as positioning references and placed on the platform of the drilling equipment. Without disassembling the fixture, the symmetrical inclined hole processing of the curved pipe corner arc surface is carried out in sequence by switching the positioning references. The clamping and drilling steps employ the symmetrical inclined hole drilling device for the curved pipe corner arc surface as described in claim 1. The first and second support surfaces simultaneously support and tighten the first and second ends of the curved pipe. The first and second pressing surfaces symmetrically clamp the arc surface at the corner of the curved pipe. The symmetrical inclined holes for the curved pipe corner arc surface are machined using the first and second drilling reference planes, respectively.

3. The method for drilling symmetrical oblique holes on the arc surface of a bent pipe according to claim 2, characterized in that: The clamping and drilling steps employ the symmetrical oblique hole drilling device for the curved pipe corner arc surface as described in claim 1, and simultaneously support and tighten the first and second ends of the curved pipe with the head end face of the support screw (3) and the second support face, and symmetrically clamp the arc surface at the corner of the curved pipe with the first pressing surface and the second pressing surface, and respectively process the symmetrical oblique holes of the curved pipe corner arc surface with the first drilling reference plane and the second drilling reference plane.

4. The method for drilling symmetrical oblique holes on the arc surface of a bent pipe according to claim 2 or 3, characterized in that: In the clamping step, the clamping force of the first clamping surface and the second clamping surface is adjusted by rotating the screw (4).

5. The method for drilling symmetrical oblique holes on the arc surface of a bent pipe according to claim 3, characterized in that: In the clamping step, the supporting and tightening force of the first end of the bend is adjusted by rotating the support screw (3).

6. The method for drilling symmetrical oblique holes on the arc surface of a bent pipe according to claim 2 or 3, characterized in that: In the drilling step, a bench drill is used to machine symmetrical inclined holes.

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