Key connection workpiece machining method and system

Abstract

The invention discloses a key connection workpiece machining method and system, and belongs to the technical field of key connection workpiece machining. The machining method comprises the steps that first machining is conducted on the outer side of one end of a workpiece to form a first key connection groove; the workpiece is placed in a key connection workpiece machining system to be clamped, the first key connection groove serves as a first machining reference site, the projection site, on one side of the workpiece, of the first machining reference site serves as a second machining reference site, and the connecting line of the first machining reference site and the second machining reference site serves as a first machining reference line; the axis, perpendicular to the first machining datum line in the horizontal plane direction, of the inner diameter of the workpiece is a second machining datum line, and the positions, located on the workpiece, of the two ends of the second machining datum line are the third machining datum position and the fourth machining datum position respectively. And carrying out second machining on the third machining reference site or the fourth machining reference site far away from one end of the first key connection groove to obtain a second key connection groove. Therefore, the problem that an existing key connection workpiece is low in machining precision is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of key-connected workpiece processing, and in particular to a key-connected workpiece processing method and system. Background Art

[0002] Key connection is a common connection method, which is used for circumferential orientation between two parts of a rotating body, and plays a role in preventing the parts from circumferential rotation or transmitting torque. The key connection of the parts processed this time requires keyways to be machined on the shaft and in the hole, which is generally processed by milling. Due to the processing surface and tool, milling can only process grooves with rounded corners. Since the part is a long cylindrical thin-walled part with a keyway located in the thin-wall cavity, in order to increase the matching surface and ensure the stability of the key connection, the keyway on the thin wall is designed as a right-angle keyway, and the solid keyway cannot be processed by milling.

[0003] For keyways with high-precision position dimensions in two different directions and different structural positions on a part, one is located On the outer circle, the other is a high-precision right-angle keyway in the thin-walled cavity. It is impossible to complete the processing of one type of work in one process. The processing of the two grooves requires repeated positioning and repeated clamping. The selection of processing types, the selection of part datums, the datum accuracy, and the fixture accuracy directly affect the realization of the part structure and the guarantee of dimensional accuracy. Therefore, the existing processing methods have certain unreliability and defects in datum selection, datum accuracy, and fixture clamping and positioning methods, and cannot efficiently and reliably guarantee the processing of high-precision grooves of parts.

[0004] The traditional key connection groove processing method uses A datum (the largest outer circle of the workpiece) for centering, end face positioning, and keyway 1 orientation as the datum design fixture. The following problems exist during EDM:

[0005] a) Fixture positioning and orientation method: The "V"-shaped surface is used to determine the center by the outer circle A reference, the end face is placed flat on the equipment platform for axial positioning, and the boss is inserted into the groove 1 for circumferential orientation. Since the size of the part A reference is The dimensional tolerance is large, and it takes a lot of time to find the A reference center when clamping the parts, and it is difficult to ensure the symmetry error requirement of 0.03mm; the end face axial positioning is used, and the end face and the A reference plane are not processed in the same process, the verticality error is large, and it takes a lot of time to straighten the end face before processing, and it is easy to cause the keyway to be not perpendicular to the A reference, resulting in angle and symmetry error problems.

[0006] b) Fixture fastening method: Tighten three top blocks with a total of 3 screws. The three top blocks hold the outer circle A reference. Since the A reference is a large cavity thin-walled part with a wall thickness of only 3mm, tightening the screws can easily cause the A reference to deform, and there is no axial fixation of the part.

[0007] The above processing method has the problems of poor positioning accuracy, part deformation, poor clamping stability and low clamping efficiency. Summary of the invention

[0008] In order to solve the problem of low machining precision of existing key-connected workpieces, the present invention provides a key-connected workpiece machining method and system.

[0009] In a first aspect, the present invention provides a key-connected workpiece processing method, comprising the following steps:

[0010] Performing a first machining operation on the outer side of one end of the workpiece to form a first key connection groove;

[0011] The workpiece is placed in a key-connected workpiece processing system for clamping. The central axis of the outer circle of the workpiece is used as a positioning reference. When the axis runout deviation does not exceed a first preset runout range, the workpiece clamping is completed.

[0012] The first key connection groove is used as the first processing reference position for the second processing, and the projection position extending from the first processing reference position to one side of the workpiece in the horizontal plane direction is the second processing reference position. The first processing reference position corresponds to the second processing reference position. The connecting line between the first processing reference position and the second processing reference position is the first processing reference line, and the axis perpendicular to the first processing reference line in the horizontal plane direction along the inner diameter of the workpiece is the second processing reference line. The positions at both ends of the second processing reference line located on the inner side of the workpiece are the third processing reference position and the fourth processing reference position, respectively. The third processing reference position and the fourth processing reference position are moved in the vertical direction to the end of the workpiece away from the first key connection groove, and the second processing is performed at the third processing reference position or the fourth processing reference position to obtain a second key connection groove. The second key connection groove is a rectangular groove.

[0013] According to one embodiment of the present invention, the second processing comprises the following steps:

[0014] According to the third processing reference position or the fourth processing reference position as the symmetry center of the second key connection groove, the electrode is used to perform rough processing in the area having the symmetry center, and the first discharge gap of the electrode is adjusted according to the processing size of the second key connection groove, and the second key connection groove is processed to the first processing allowance;

[0015] The first machining allowance is finely machined using the electrode, and the second discharge gap of the electrode is adjusted according to the first machining allowance to obtain the second key connection groove.

[0016] According to an embodiment of the present invention, the included angle between the projection lines of the first key connection groove and the second key connection groove extending in the horizontal plane is 90°±3°.

[0017] According to one embodiment of the present invention, the clamping comprises the following steps:

[0018] placing a clamping block in the first annular groove of the workpiece;

[0019] The workpiece is placed in the positioning cavity of the positioning table, and the workpiece is moved in a direction close to the directional block in the positioning cavity until the first key connection groove is sleeved on the directional block;

[0020] The tensioning pin passes through the first through hole of the positioning platform until the tensioning pin abuts against the tensioning block.

[0021] In a second aspect, the present invention provides a key-connected workpiece processing system, comprising:

[0022] Workpiece, positioning base and jacking assembly;

[0023] The workpiece includes a cylinder and a positioning body, the positioning body is fixedly connected to one end of the cylinder, the positioning body is coaxial with the cylinder, one end of the positioning body is provided with a first annular boss, a second annular boss and a first annular groove, the first annular groove is located on the first annular boss and the second annular boss, the second annular boss is located between the first annular groove and the cylinder, the first annular boss is provided with a first keyway, and the second annular boss is provided with a second keyway;

[0024] The positioning base comprises a positioning platform and an orientation block, the positioning platform is provided with a positioning cavity, an orientation groove and a first through hole, the first through hole is arranged opposite to the orientation groove, the first through hole is communicated with the orientation groove, the workpiece is located in the positioning cavity, one end of the orientation block is located in the orientation groove, the first key groove, the second key groove and the first annular groove constitute a first key connection groove, and the other end of the orientation block abuts against the first key connection groove;

[0025] The tightening assembly includes a tightening block and a tightening pin. The tightening pin is connected to the positioning platform through the first through hole. The tightening block is fitted with the first annular groove, and the tightening pin is in contact with the tightening block.

[0026] According to an embodiment of the present invention, the positioning platform is provided with a second annular groove, the second annular groove is located in the positioning cavity, and one end of the cylinder connected to the positioning body is located in the second annular groove.

[0027] According to an embodiment of the present invention, the positioning cavity penetrates the positioning platform in the vertical direction, the height of the positioning body is smaller than the height of the directional groove in the vertical direction, and the positioning body is suspended in the positioning cavity.

[0028] According to an embodiment of the present invention, the diameter of the positioning cavity is larger than the outer diameter of the workpiece, and an open semicircular structure is formed between the workpiece and the positioning platform away from the directional groove.

[0029] According to an embodiment of the present invention, the positioning base further includes an orientation pin, the positioning platform is provided with a second through hole connected to the orientation pin, and the orientation block is provided with a connecting hole connected to the orientation pin.

[0030] According to one embodiment of the present invention, the tightening block is provided with an arc surface abutting against the first annular groove, the arc surface is adapted to the bottom wall of the first annular groove, the height of the tightening block in the vertical direction is consistent with the height of the first annular groove, the curvature of the arc surface is consistent with the curvature of the first annular groove, the thickness of the tightening block is less than or equal to the depth of the first annular groove, and the ratio of the arc length of the arc surface to the arc length of the first annular groove is 1:5~6.

[0031] According to an embodiment of the present invention, the tensioning pin is provided with an abutting surface abutting against the tensioning block, the abutting surface is matched with the wall surface of the tensioning block, and the tensioning pin is threadedly connected to the first through hole.

[0032] In order to solve the problem of low machining precision of existing key-connected workpieces, the present invention has the following advantages:

[0033] 1. The method and system of the present invention break through the limitations of high-precision parts processing, uncontrollable repeated positioning errors, and the inability of tools to process right-angle grooves, and provide a processing solution for such thin-walled and easily deformed parts with high-precision dimensions, symmetry, and high-precision position dimensions.

[0034] 2. The key-connected workpiece processing system of the present invention provides a structural solution in terms of clamping convenience, clamping reliability and workpiece protection, thereby improving the processing efficiency while increasing the qualification rate.

[0035] 3. It overcomes the technical barriers in the existing workpiece precision machining process and provides reliable technical support for promoting mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flow chart of a key-connected workpiece processing method according to an embodiment is shown;

[0037] Figure 2 An exploded schematic diagram of a key-connected workpiece processing system according to an embodiment is shown;

[0038] Figure 3 A schematic side view of a keyed workpiece processing system according to an embodiment is shown;

[0039] Figure 4 Shows Figure 3 AA section diagram of ;

[0040] Figure 5 Shows Figure 4 Schematic diagram of the enlarged structure at C in the middle;

[0041] Figure 6 A schematic diagram of a workpiece according to an embodiment is shown;

[0042] Figure 7 A schematic diagram of a positioning base according to an embodiment is shown.

[0043] Figure markings: 01-workpiece; 11-cylinder; 12-first annular boss; 13-second annular boss; 14-first annular groove; 15-first keyway; 16-second keyway; 17-second key connecting groove; 02-positioning base; 21-positioning platform; 22-positioning cavity; 23-orientation groove; 24-first through hole; 25-second annular groove; 26-second through hole; 27-orientation block; 28-orientation pin; 29-connecting hole; 03-tightening assembly; 31-tightening block; 32-tightening pin; 33-pushing pin. DETAILED DESCRIPTION

[0044] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, rather than implying any limitation on the scope of the present disclosure.

[0045] As used herein, the term "including" and its variants are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "based at least in part on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal" and the like is based on the orientation or position relationship shown in the accompanying drawings. These terms are mainly for better describing the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation. In addition, in addition to being used to indicate an orientation or position relationship, some of the above terms may also be used to indicate other meanings, such as the term "upper" may also be used to indicate a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to the specific circumstances. In addition, the terms "install", "set", "provided with", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be an internal connection between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances. In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0046] In a first aspect, this embodiment discloses a method for machining a key-connected workpiece, such as Figure 1 As shown, the following steps are included:

[0047] A first key connection groove is first machined on the outer side of one end of the workpiece 01;

[0048] The workpiece 01 is placed in the key-connected workpiece processing system for clamping. The central axis of the outer circle of the workpiece 01 is used as the positioning reference. When the axis runout deviation does not exceed the first preset runout range, the clamping of the workpiece 01 is completed;

[0049] The first key connection groove is used as the first processing reference position for the second processing, and the projection position of the first processing reference position extending to one side of the workpiece 01 along the horizontal plane direction is the second processing reference position. The first processing reference position corresponds to the second processing reference position. The connecting line of the first processing reference position and the second processing reference position is the first processing reference line. The axis perpendicular to the first processing reference line in the horizontal plane direction along the inner diameter of the workpiece 01 is the second processing reference line. The positions at both ends of the second processing reference line located on the inner side of the workpiece 01 are the third processing reference position and the fourth processing reference position respectively. The third processing reference position and the fourth processing reference position are moved in the vertical direction to the end of the workpiece 01 away from the first key connection groove, and the second processing is performed at the third processing reference position or the fourth processing reference position to obtain the second key connection groove 17. The second key connection groove 17 is a rectangular groove.

[0050] In this embodiment, two processes are required to process the first key connection groove and the second key connection groove 17. The groove processed first can be selected as the orientation reference. The mating surface of the first key connection groove is longer and more reliable as the orientation reference. The first key connection groove is selected as the orientation reference. Specifically, the design size of the first key connection groove is As a directional reference, the dimensional accuracy of the first key connection groove can be increased to IT7, that is, processed to The symmetry error of the A datum (the description of the A datum in this article refers to the maximum outer circle of the workpiece 01) is 0.03mm. The symmetry error of the A datum can be improved to 0.02mm, and the redundant precision error is allocated to the clamping error. Selection of positioning datum and process control, workpiece 01 is a rotating body structure, the first key connection groove and the second key connection groove 17 are distributed around a center circumference on the workpiece 01, the symmetry error of the first key connection groove and the second key connection groove 17 to the A datum is 0.03mm, then their center datum is the outer circle A, but the outer circle A is thin-walled, and positioning clamping can easily cause deformation. After processing the second key connection groove 17 and loosening the workpiece 01, the shape of the workpiece 01 changes, and the symmetry error of the workpiece 01 cannot be guaranteed to be qualified. Therefore, the clamping positioning surface should be selected on the outer circle with a stable structure and far away from the second key connection groove 17. Transform the center reference to prevent deformation during clamping.

[0051] In some embodiments, the first preset vibration range is less than or equal to 0.2 mm to 0.3 mm.

[0052] In some embodiments, the second key connection groove 17 is a right-angle groove.

[0053] According to one embodiment of the present invention, the second processing comprises the following steps:

[0054] According to the third processing reference position or the fourth processing reference position as the symmetry center of the second key connection groove 17, the electrode is used to perform rough processing in the area having the symmetry center, and the first discharge gap of the electrode is adjusted according to the processing size of the second key connection groove 17, and the second key connection groove 17 is processed to the first processing allowance;

[0055] The first machining allowance is finely machined using the electrode, and the second discharge gap of the electrode is adjusted according to the first machining allowance, so as to obtain the second key connection groove 17 through machining.

[0056] In this embodiment, the precision of machining the second key connection groove 17 is further improved by combining rough machining and fine machining.

[0057] In some embodiments, the first discharge gap and the second discharge gap are electrodes whose size is at least 0.4 mm smaller than the keyway to be machined. Preferably, the first discharge gap and the second discharge gap on one side are at least 0.2 mm.

[0058] In some embodiments, the second discharge gap is larger than the first discharge gap.

[0059] In some embodiments, the first machining allowance is 0.1 mm to 0.2 mm.

[0060] According to an embodiment of the present invention, the included angle between the projection lines of the first key connection groove and the second key connection groove 17 extending in the horizontal plane is 90°±3°.

[0061] In this embodiment, the processing accuracy of the second key connecting groove 17 is guaranteed.

[0062] According to one embodiment of the present invention, the clamping comprises the following steps:

[0063] The clamping block 31 is placed in the first annular groove 14 of the workpiece 01;

[0064] The workpiece 01 is placed in the positioning cavity 22 of the positioning table 21, and the workpiece 01 is moved in a direction close to the directional block 27 in the positioning cavity until the first key connection groove is sleeved on the directional block 27;

[0065] The tensioning pin 32 passes through the first through hole 24 of the positioning platform 21 until the tensioning pin 32 abuts against the tensioning block 31 .

[0066] In this embodiment, specifically, the key connection workpiece processing system positioning and orientation method: the first key connection groove of the workpiece 01 is aligned with the orientation block 27 on the positioning table 21 for installation as orientation, so as to position the upper semicircle of the positioning cavity 22, such as Figure 4 As shown, the positioning table 21 holds the workpiece The outer circle center is positioned, and the workpiece 01 step surface is used for axial positioning. The semicircular positioning surface of the positioning cavity 22 is processed as follows: With artifacts The outer circle matching clearance is 0.01mm~0.03mm, ensuring that the center positioning error is controlled within 0.03mm. After clamping is completed, re-align the A reference center within 0.03mm. This operation can eliminate the positioning error of the fixture clamping.

[0067] In some embodiments, before machining the first key connection groove and the second key connection groove 17, a lathe is arranged to turn the A reference (outer circle of the workpiece 01) of the workpiece 01. And the step surface between the two outer circles, tighten the outer circle Tolerance is The tolerance is increased to IT6, and the step surface is used as the axial positioning reference. The two center references and the axial reference surface are processed in one process. The coaxiality error of the two outer circles is stably controlled at 0.008mm, and the perpendicularity error between the step surface and the A reference is also controlled at 0.008mm. The dimensional accuracy of the reference surface and the strict and stable control of the form and position tolerances in all directions are prerequisites for ensuring the high-precision processing of workpiece 01.

[0068] In some embodiments, the processing method of the second key connection groove 17 includes the following steps:

[0069] (1) preparing an electrode, selecting an electrode size according to the size of the second key connection groove 17, specifically, when the size of the second key connection groove 17 to be processed is 4H7, the electrode thickness is 3.6±0.002 mm, the width is 14 mm, and the height is 49 mm. The material of the electrode includes copper-tungsten alloy, and the electrode is further ground to obtain an electrode of the required size;

[0070] (2) The electrode is mounted on a precision EDM machine, the groove depth is in the Z direction, and the groove is made laterally by electrode discharge ablation (i.e., electrode discharge groove is made in the X direction);

[0071] (3) The key-connected workpiece processing system is installed on the equipment platform. The runout of the straightened long side surface (i.e., the side surface in the X direction) of the horizontal plane of the key-connected workpiece processing system is less than 0.003 mm, and the runout of the leveling end surface is 0.005 mm;

[0072] (4) Clamp workpiece 01, workpiece While the outer circle is loaded into the positioning cavity 22, the first key connection groove of the workpiece 01 is aligned with the orientation block 27 on the positioning table 21. After the workpiece 01 is loaded, the workpiece 01 is pressed down by hand and the locking pin 32 is tightened. The clamping of the workpiece 01 is completed.

[0073] (5) Verify the reliability of the clamping of workpiece 01. The end face runout of workpiece 01 can be leveled within 0.01mm, and the center axis runout of the A reference outer circle of workpiece 01 can be aligned within 0.02mm.

[0074] (6) Locate the processing position, move the electrode, locate the center axis of the outer circle of the A datum of the workpiece 01, and touch two points in the X or Y direction. The center of the line connecting the four points is the center of the A datum of the workpiece 01. Then use the electrode to touch four points on the upper end surface of the workpiece 01 to find the starting point in the Z direction of the workpiece 01, set the coordinates, and find the groove position according to the preset size of the second key connection groove 17. The groove is divided into rough processing and fine processing, the discharge gap and the processing depth are set, and the second key connection groove 17 is processed.

[0075] In a second aspect, this embodiment provides a key-connected workpiece processing system, such as Figures 2 to 7 As shown, including:

[0076] Workpiece 01, positioning base 02 and clamping assembly 03;

[0077] The workpiece 01 includes a cylinder 11 and a positioning body, the positioning body is fixedly connected to one end of the cylinder 11, the positioning body is coaxial with the cylinder 11, and one end of the positioning body is provided with a first annular boss 12, a second annular boss 13 and a first annular groove 14, the first annular groove 14 is located at the first annular boss 12 and the second annular boss 13, the second annular boss 13 is located between the first annular groove 14 and the cylinder 11, the first annular boss 12 is provided with a first keyway 15, and the second annular boss 13 is provided with a second keyway 16;

[0078] The positioning base 02 includes a positioning platform 21 and an orientation block 27. The positioning platform 21 is provided with a positioning cavity 22, an orientation groove 23 and a first through hole 24. The first through hole 24 is arranged opposite to the orientation groove 23. The first through hole 24 is connected to the orientation groove 23. The workpiece 01 is located in the positioning cavity 22. One end of the orientation block 27 is located in the orientation groove 23. The first key groove 15, the second key groove 16 and the first annular groove 14 constitute a first key connection groove. The other end of the orientation block 27 abuts against the first key connection groove.

[0079] The tightening assembly 03 includes a tightening block 31 and a tightening pin 32 . The tightening pin 32 is connected to the positioning platform 21 through the first through hole 24 . The tightening block 31 is fitted with the first annular groove 14 , and the tightening pin 32 is in contact with the tightening block 31 .

[0080] In this embodiment, the workpiece 01 is clamped in the following manner: the first annular groove 14 is loaded with the top clamping block 31, and the positioning cavity 22 of the positioning platform 21 is loaded into the first annular groove 14. Figure 4 As shown, the first annular groove 14 is aligned with the orientation block 27. After the workpiece 01 is aligned, the end face of the workpiece 01 is pressed downward by hand (i.e., in the axial direction), and the other hand is used to turn and tighten the top pin 32 to fix the workpiece 01. Specifically, since the workpiece 01 will vibrate when the electric spark machine of the motor discharges and processes the workpiece 01, the workpiece 01 must be fastened to the work platform using a key connection workpiece processing system during the processing. The workpiece 01 needs to be fixed in the circumferential, axial and center positions. The circumferential fixation is that the orientation block 27 is inserted into the first key connection groove of the workpiece 01 to prevent the workpiece 01 from rotating. The center position and the axial direction are fixed by tightening the top pin 32, and the end face of the top pin 32 is tightened to the center position of the workpiece 01 (on the same center line as the first key connection groove) to generate a force F toward the center line of the workpiece 01. x1 Preferably, the wall surface of one end of the locking pin 32 abutting against the locking block 31 is a chamfered structure. When the locking pin 32 is tightened, the chamfered conical surface of the locking pin 32 generates a force F on the step of the workpiece 01, and a force F is generated on the center position of the workpiece 01 (on the same center line as the first key connection groove). x1 +F x2 And the axial downward force F y ,like Figure 5 As shown, the forces in two directions tighten the workpiece 01.

[0081] In some embodiments, the outer diameter of the first annular boss 12 is less than or equal to the outer diameter of the second annular boss 13. By setting the outer diameter of the first annular boss 12 and the outer diameter of the second annular boss 13, the stability of clamping the workpiece 01 is further improved.

[0082] In some embodiments, Figure 2 and Figure 4 As shown, the tensioning pin 32 is connected with a pull pin 33 to facilitate tightening the tensioning pin 32 .

[0083] According to one embodiment of the present invention, Figure 2 and Figure 7 As shown, the positioning platform 21 is provided with a second annular groove 25 , the second annular groove 25 is located in the positioning cavity 22 , and one end of the cylinder 11 connected to the positioning body is located in the second annular groove 25 .

[0084] In this embodiment, the second annular groove 25 is provided to further improve the stability of clamping the workpiece 01 .

[0085] According to one embodiment of the present invention, Figure 2 and Figure 4 As shown, the positioning cavity 22 passes through the positioning platform 21 in the vertical direction, the height of the positioning body is smaller than the height of the directional groove 23 in the vertical direction, and the positioning body is suspended in the positioning cavity 22 .

[0086] In this embodiment, the positioning body is suspended in the positioning cavity 22, so that the powder chips generated by processing can directly fall onto the workbench below the positioning cavity 22 and no longer contact the workpiece 01, thereby avoiding scratches on the workpiece 01 when the workpiece 01 is taken out.

[0087] In some embodiments, Figure 1 As shown, the orientation block 27 adopts a "T"-shaped orientation block 27, and the orientation groove 23 is also a "T"-shaped orientation groove 23. The "T"-shaped orientation block 27 can effectively increase the matching stability of the orientation block 27 and prevent the orientation block 27 from falling off the positioning base 02. The orientation block 27 and the positioning base 02 adopt a high-precision interference fit. The upper positioning semicircular surface of the positioning cavity 22 of the positioning table 21 and the orientation groove 23 are formed by high-precision slow wire cutting in one time. The symmetry accuracy is controlled at 0.005mm, and the orientation block 27 is processed to 4.01mm. The matching clearance between the orientation block 27 and the first key connection groove of the workpiece 01 is 0.01mm~0.022mm. To ensure the accuracy of the angle size of the first key connection groove and the second key connection groove 17 of 90°±3°, the matching clearance between the first key connection groove and the orientation block 27 is controlled within 0.04mm, so that the clamping accuracy of the key-connected workpiece processing system and the workpiece 01 meets the angle error requirement.

[0088] According to an embodiment of the present invention, the diameter of the positioning cavity 22 is larger than the outer diameter of the workpiece 01 , and an open semicircular structure is formed between the workpiece 01 and the positioning platform 21 at a side away from the directional groove 23 .

[0089] By setting up the open semicircle structure, after the workpiece 01 is processed, the tightening pin 32 is loosened and tightened, and the workpiece 01 moves toward the open semicircle surface of the positioning cavity 22 and is taken out upward. Since electrospark processing will produce powder chips in the bath, after the processing is completed, the bath liquid retreats, and the powder chips enter the gap between the workpiece 01 and the positioning table 21, making it difficult to take out the workpiece 01, and there is a scratch problem after taking it out. The design of the open semicircle is to solve the problem of difficulty in taking out the workpiece 01 and scratching the workpiece 01. The end face of the workpiece 01 is suspended in the air to allow the step surface, i.e. the positioning surface, to fully contact the plane of the fixture to ensure reliable clamping, and the bath liquid can form a bath liquid retreat path between the open semicircle and the workbench to avoid the above-described bath liquid powder chips being stuck between the workpiece 01 and the positioning table 21.

[0090] According to one embodiment of the present invention, Figure 2 and Figure 4 As shown, the positioning base 02 further includes a directional pin 28 , the positioning platform 21 is provided with a second through hole 26 connected to the directional pin 28 , and the directional block 27 is provided with a connecting hole 29 connected to the directional pin 28 .

[0091] In this embodiment, by providing the directional pin 28 and the connecting hole 29 , it is convenient to tighten the positioning pin so that the positioning block cooperates with the clamping assembly 03 to fix the workpiece 01 , thereby improving the positioning stability of the workpiece 01 .

[0092] Preferably, the positioning pin is threadedly connected to the positioning platform 21 through the second through hole 26 .

[0093] According to one embodiment of the present invention, Figure 1 As shown, the tightening block 31 is provided with an arc surface abutting against the first annular groove 14, the arc surface is adapted to the bottom wall of the first annular groove 14, the height of the tightening block 31 in the vertical direction is consistent with the height of the first annular groove 14, the curvature of the arc surface is consistent with the curvature of the first annular groove 14, the thickness of the tightening block 31 is less than or equal to the depth of the first annular groove 14, and the ratio of the arc length of the arc surface to the arc length of the first annular groove 14 is 1:5~6.

[0094] In this embodiment, the clamping block 31 is made of a material with a lower hardness than the workpiece 01 and is made into an arc that fits the mating surface of the first annular groove 14 of the workpiece 01. The outer circle of the clamping block 31 is lower than the outer circle surface of the first annular groove 14 and can be loaded into and taken out of the positioning cavity 22 along with the workpiece 01. The clamping block 31 has the function of protecting the outer circle surface of the workpiece 01 and tightening the clamping pin 32 on two active surfaces at the same time.

[0095] According to one embodiment of the present invention, Figure 1As shown, the tensioning pin 32 is provided with an abutting surface abutting against the tensioning block 31 , the abutting surface is matched with the wall surface of the tensioning block 31 , and the tensioning pin 32 is threadedly connected with the first through hole 24 .

[0096] In this embodiment, the setting of the abutting surface of the clamping block 31 further facilitates the clamping pin 32 to cooperate with the clamping block 31 to position the workpiece 01, and the clamping pin 32 is threadedly connected to the first through hole 24 to facilitate installation, fastening and disassembly.

[0097] In the present invention, since the keyway size is (First key connection groove), for the outer circle of workpiece 01 (A benchmark) The symmetry error is not less than 0.03mm, the first key connection groove and the key groove (The second key connection groove 17) has an angle of 90°±3°. The key groove has high requirements for dimensional accuracy, position accuracy and form and position tolerance. It is processed by CNC EDM and the workpiece 01 is clamped to ensure the position accuracy of the workpiece 01 and the key groove. During the processing, the discharge gap is controlled, the electrode wear is checked and the electrode is replaced in time to ensure the dimensional accuracy of the parts. The present invention ensures a process method for high-precision groove electrical processing by a key connection workpiece processing method and a system clamping method, and realizes the problem that the existing processing method cannot ensure the processing accuracy of the workpiece 01, thereby fundamentally solving the 4H7 of the high-precision second key connection groove 17 of the workpiece 01, the symmetry error of the A reference of 0.03mm, and the 90°±3° out-of-tolerance problem with the angle dimension of the first key connection groove, as well as the processing efficiency problem, so that its qualified rate is increased from the existing 30% to 99%. By reducing the time for tightening the screws and the time for clamping and aligning, the labor intensity of the operator is reduced. It used to take 90 minutes to complete one piece, but now it only takes 60 minutes to complete one piece, and the efficiency is increased by 33%.

[0098] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in actual applications, various changes may be made thereto in form and detail without departing from the scope of the present disclosure.

Claims

1. A method for processing a key-connected workpiece, characterized in that: The steps include: Performing a first machining operation on the outer side of one end of the workpiece to form a first key connection groove; The workpiece is placed in a key-connected workpiece processing system for clamping. The central axis of the outer circle of the workpiece is used as a positioning reference. When the axis runout deviation does not exceed a first preset runout range, the workpiece clamping is completed. The first key connection groove is used as the first processing reference position for the second processing, and the projection position extending from the first processing reference position to one side of the workpiece in the horizontal plane direction is the second processing reference position. The first processing reference position corresponds to the second processing reference position. The connecting line between the first processing reference position and the second processing reference position is the first processing reference line, and the axis perpendicular to the first processing reference line in the horizontal plane direction along the inner diameter of the workpiece is the second processing reference line. The positions at both ends of the second processing reference line located on the inner side of the workpiece are the third processing reference position and the fourth processing reference position, respectively. The third processing reference position and the fourth processing reference position are moved in the vertical direction to the end of the workpiece away from the first key connection groove, and the second processing is performed at the third processing reference position or the fourth processing reference position to obtain a second key connection groove. The second key connection groove is a rectangular groove.

2. A key-connected workpiece processing method according to claim 1, characterized in that: The second processing comprises the following steps: According to the third processing reference position or the fourth processing reference position as the symmetry center of the second key connection groove, the electrode is used to perform rough processing in the area having the symmetry center, and the first discharge gap of the electrode is adjusted according to the processing size of the second key connection groove, and the second key connection groove is processed to the first processing allowance; The first machining allowance is finely machined using the electrode, a second discharge gap of the electrode is adjusted according to the first machining allowance, and the second key connection groove is machined.

3. A key-connected workpiece processing method according to claim 2, characterized in that: The included angle between the projection lines of the first key connection groove and the second key connection groove extending in the horizontal plane is 90°±3°.

4. A key-connected workpiece processing method according to claim 1, characterized in that: The clamping comprises the following steps: placing a clamping block in the first annular groove of the workpiece; The workpiece is placed in the positioning cavity of the positioning table, and the workpiece is moved in a direction close to the directional block in the positioning cavity until the first key connection groove is sleeved on the directional block; The tensioning pin passes through the first through hole of the positioning platform until the tensioning pin abuts against the tensioning block.

5. A key-connected workpiece processing system applied to a key-connected workpiece processing method as claimed in any one of claims 1 to 4, characterized in that: include: Workpiece, positioning base and jacking assembly; The workpiece includes a cylinder and a positioning body, the positioning body is fixedly connected to one end of the cylinder, the positioning body is coaxial with the cylinder, one end of the positioning body is provided with a first annular boss, a second annular boss and a first annular groove, the first annular groove is located on the first annular boss and the second annular boss, the second annular boss is located between the first annular groove and the cylinder, the first annular boss is provided with a first keyway, and the second annular boss is provided with a second keyway; The positioning base comprises a positioning platform and an orientation block, the positioning platform is provided with a positioning cavity, an orientation groove and a first through hole, the first through hole is arranged opposite to the orientation groove, the first through hole is communicated with the orientation groove, the workpiece is located in the positioning cavity, one end of the orientation block is located in the orientation groove, the first key groove, the second key groove and the first annular groove constitute a first key connection groove, and the other end of the orientation block abuts against the first key connection groove; The tightening assembly includes a tightening block and a tightening pin. The tightening pin is connected to the positioning platform through the first through hole. The tightening block is fitted with the first annular groove, and the tightening pin is in contact with the tightening block.

6. The key connection workpiece processing system according to claim 5, characterized in that: The positioning platform is provided with a second annular groove, the second annular groove is located in the positioning cavity, and one end of the cylinder connected to the positioning body is located in the second annular groove.

7. The key-connected workpiece processing system according to claim 6, characterized in that: The positioning cavity penetrates the positioning platform in the vertical direction, the height of the positioning body is smaller than the height of the directional groove in the vertical direction, and the positioning body is suspended in the positioning cavity.

8. The key-connected workpiece processing system according to claim 5, characterized in that: The diameter of the positioning cavity is larger than the outer diameter of the workpiece, and an open semicircular structure is formed between the workpiece and the positioning platform away from the directional groove.

9. The key-connected workpiece processing system according to claim 5, characterized in that: The positioning base also includes a directional pin, the positioning platform is provided with a second through hole connected to the directional pin, and the directional block is provided with a connecting hole connected to the directional pin.

10. The key-connected workpiece processing system according to claim 5, characterized in that: The tightening block is provided with an arc surface abutting against the first annular groove, the arc surface is adapted to the bottom wall of the first annular groove, the height of the tightening block in the vertical direction is consistent with the height of the first annular groove, the curvature of the arc surface is consistent with the curvature of the first annular groove, the thickness of the tightening block is less than or equal to the depth of the first annular groove, and the ratio of the arc length of the arc surface to the arc length of the first annular groove is 1:5 to 6.

11. The key-connected workpiece processing system according to claim 5, characterized in that: The tensioning pin is provided with an abutting surface abutting against the tensioning block, the abutting surface is matched with the wall surface of the tensioning block, and the tensioning pin is threadedly connected with the first through hole.

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