CN108098474A - A kind of processing method of fixture and eccentric drill bushing for eccentric drill bushing processing - Google Patents

Abstract

The invention discloses the processing methods of a kind of fixture for eccentric drill bushing processing and eccentric drill bushing, there is a circular shape through hole in the upper surface of cylindrical fixture body (1), circular shape through hole includes the first circular hole and outer diameter second circular hole smaller than the first circular hole, the axis of circular shape through hole parallel to cylindrical fixture body (1) axis, and the vertical interval of two axis be H.By the eccentric accurate clamping of drill bushing part (2) to be processed on special tooling, while ensure accurate clamping of the fixture on internal grinder, select suitable grinding tool and parameter, grinding is carried out to part.The present invention can realize small lot processing of such eccentric drill bushing part in plain grinding equipment, while improve processing efficiency, reduce the processing cost of such part.

Description

A fixture for processing eccentric drill sleeves and a processing method for eccentric drill sleeves

technical field

The invention belongs to the field of mechanical processing, and relates to a specific processing and manufacturing method for an eccentric drill sleeve clamp in a fixture of a tooling drilling machine.

Background technique

The eccentric drill sleeve in the tooling fixture is the key part of the fixture in the machining of aviation parts. The quality directly affects the dimensional accuracy and position accuracy of the holes of the aeroengine parts. At present, the processing of such eccentric drill sleeve parts is mostly processed by slow wire-feeding or high-precision CNC coordinate grinding. Although this type of processing can meet the requirements, the processing cost is too high, which is not conducive to the processing of small batches of parts.

Contents of the invention

The technical problem to be solved by the present invention is to provide a fixture for processing eccentric drill bushings and a processing method for eccentric drill bushings. The fixture is simple to manufacture and can solve the small batch processing of such eccentric drill bushing parts on ordinary grinding equipment. , while improving processing efficiency and reducing the processing cost of such parts.

Technical scheme of the present invention is as follows:

A fixture for processing eccentric drill sleeves, comprising a cylindrical clamping body whose upper and lower end surfaces are parallel, the upper end surface of the cylindrical clamping body has a circular stepped through hole, and the circular stepped through hole includes a first circular hole and an outer diameter A second round hole smaller than the first round hole, the axis of the circular stepped through hole is parallel to the axis of the cylindrical clamp body, and the vertical distance between the two axes is H;

The upper end surface of the cylindrical clamp body is also provided with a matching notch along the diameter direction of the end surface, the cross section of the matching notch is rectangular, and its width is smaller than the outer diameter of the first circular hole and larger than the outer diameter of the second circular hole. Its depth is smaller than that of the first circular hole, and the axis of the matching notch perpendicularly intersects the axis of the circular stepped through hole and the axis of the cylindrical clamp body.

The lower end of the side surface of the cylindrical clamp body has a ring-shaped protrusion, which serves as the clamping surface for clamping, and the cylindrical surface of the clamping body is the front face.

The thickness of the cylindrical clamping body is smaller than the height of the eccentric drill sleeve part to be processed.

A method for processing an eccentric drill sleeve using the above fixture, comprising the following steps:

Step 1, select the fixture, and determine that the eccentric value of the eccentric drill sleeve part to be processed is consistent with the vertical distance H between the axis of the cylindrical clamp body and the axis of the circular stepped through hole;

Step 2, install the fixture on the internal grinding machine, and find out that the outer circle runout of the fixture meets the requirements;

Step 3, the interference fit of the eccentric drill bushing parts to be processed is put into the cylindrical clamp body to ensure that the matching notches of the cylindrical clamp body and the two sides of the eccentric drill bushing parts are in clearance fit, and the second round hole on the cylindrical clamp body is The inner cylindrical surface is interference fit with the outer cylindrical surface of the small end of the eccentric drill sleeve part to be processed;

Step 4, determine the grinding head and grinding parameters, and grind the eccentric hole of the eccentric drill sleeve part to be processed.

The invention solves the problem of low processing efficiency of the eccentric drill sleeve, meets the use requirements, and greatly reduces the processing cost compared with the existing processing method.

Description of drawings

Fig. 1 is the sectional schematic diagram of the eccentric drill sleeve to be processed;

Fig. 2 is the left view of Fig. 1;

Fig. 3 is the three-dimensional structural diagram of fixture;

Fig. 4 is a top view of the eccentric drill sleeve to be processed and the clamp after being clamped;

Fig. 5 is a schematic cross-sectional view of A-A after the eccentric drill bush to be processed and the fixture are clamped in Fig. 4 .

Detailed ways

The fixture and the processing method of the eccentric drill bushing according to the present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in FIG. 1 and FIG. 2 , it is a schematic structural diagram of the eccentric drill sleeve part 2 to be processed in the present invention, and the eccentric value of the eccentric hole 5 is H.

As shown in Figures 3 to 5, first design the fixture: design a special series of eccentric fixtures according to the clamping and positioning methods of the processing machine tool and the structural characteristics of the workpiece, as shown in Figure 3. Then, according to the structure of the fixture parts and the machining accuracy of the machine tool, the dimensional tolerance of each part of the fixture is reasonably allocated. According to the fixture process structure, formulate the best process route, reduce machining errors, improve fixture manufacturing accuracy, and ensure fixture positioning accuracy can fully meet the processing accuracy requirements of eccentric drill sleeve parts. The eccentric drill sleeve part 2 to be processed is accurately clamped on the special tooling, and at the same time, the accurate clamping of the clamp on the internal grinding machine is ensured, and the appropriate grinding tool and parameters are selected to grind the part to ensure the processing of the inner hole Dimensional accuracy and position tolerance requirements.

Specific steps are as follows:

Step 1: Design and process the positioning fixture according to the structural characteristics of the eccentric drill sleeve part 2 to be processed, so as to ensure that the vertical distance H between the axis of the cylindrical clamp body 1 and the axis of the circular stepped through hole is consistent with the eccentric value H of the eccentric hole 5, namely In Fig. 4, the tolerance of the eccentric H value between the center of the outer circle 3 of the clamp body and the center of the second circular hole meets the processing requirements of the eccentric drill sleeve;

Step 2, use the annular protrusion 8 to install the fixture on the internal grinding machine, and find out that the beating of the outer circle 3 of the fixture meets the requirements;

Step 3, put the eccentric drill sleeve part 2 to be processed into the cylindrical clamp body 1, ensure that the matching notch 6 and the two sides 9 of the eccentric drill sleeve part 2 have a clearance fit, the bottom surface fits, and the first part on the cylindrical clamp body 1 The inner cylindrical surface 4 of the second circular hole is in interference fit with the small end outer cylindrical surface 7 of the eccentric drill sleeve part 2 to be processed;

Step 4: Grinding the eccentric hole 5 of the eccentric drill sleeve with a small chrome corundum grinding head with an outer diameter of less than 8 mm and an ordinary internal grinder with a rotating speed of 8,000 to 10,000 rpm to meet the size requirements of the drawing.

The qualification rate of the parts processed by the above-mentioned fixture and method has increased from 40% to 99% now, and the processing time has been increased by 3 times compared with the slow wire processing, which ensures the fast delivery cycle of the parts and reduces the processing cost. .

Claims (4)

1. a kind of fixture for eccentric drill bushing processing, it is characterised in that：Including the parallel cylindrical fixture body in upper and lower end face (1), there is a circular shape through hole in the upper surface of the cylindrical fixture body (1), and circular shape through hole is including the first circular hole and outside Footpath second circular hole smaller than the first circular hole, the axis of the circular shape through hole parallel to cylindrical fixture body (1) axis, and The vertical interval of two axis is H；

The upper surface of the cylindrical fixture body (1) is also provided with a cooperation notch (6) along end face circular diameter direction, cooperation The rectangular in cross-section of notch (6), width are less than the first circular hole outer diameter and more than the second circular hole outer diameters, and depth is less than the first circle The depth in hole, the axis of cooperation notch (6) intersect vertically with the axis of circular shape through hole, the axis of cylindrical fixture body (1).

2. a kind of fixture for eccentric drill bushing processing according to claim 1, it is characterised in that：The cylindrical fixture There is a circle annular protrusion (8) in body (1) side surface lower end.

3. a kind of fixture for eccentric drill bushing processing according to claim 1, it is characterised in that：The cylindrical fixture The thickness of body (1) is less than the height of eccentric drill bushing part (2) to be processed.

4. a kind of eccentric drill bushing processing method using 1 or 2 or 3 fixture of claim, which is characterized in that including following step Suddenly：

Step 1 selects fixture, determine the eccentricity value of eccentric drill bushing part (2) to be processed and cylindrical fixture body (1) axis and Vertical interval H between circular shape through-bore axis is consistent；

Fixture is installed on internal grinder by step 2, and centering clamp body outer circle (3) bounce meets the requirements；

Eccentric drill bushing part (2) to be processed is fitted into cylindrical fixture body (1), ensures cooperation notch (6) and bias by step 3 Two sides (9) clearance fit of drill bushing part (2), the second circular hole inner cylinder face (4) on cylindrical fixture body (1) with it is to be processed Small end external cylindrical surface (7) interference fit of eccentric drill bushing part (2)；

Step 4 determines bistrique and grinding parameter, and the eccentric orfice (5) of eccentric bit to be processed set part (2) is ground.