A variable control fixture for deforming a thin-walled part of a crankcase cover and a processing method

Abstract

The application discloses a deformation electric control clamp for a thin-wall part of a crankcase cover, which comprises a clamp base, a rotatable rotating bearing arranged on the clamp base, an auxiliary device arranged on the rotating bearing, a back-shaped fixing support of the auxiliary device, a pair of oppositely arranged electric control clamp mounting structures arranged on the inner wall of the fixing support, a pair of detachable electric control clamps arranged on the electric control clamp mounting structures, a pair of parallel arranged right-angle plate structures arranged on one of the electric control clamp mounting structures, and a plurality of eddy current displacement sensors arranged on the right-angle plate structures. The clamp directly adjusts the deformation of the thin-wall part, and thus the annealing and normalizing treatment of the thin-wall part in advance for improving the metal structure and performance is not needed, the high requirements on the material and performance of the cutter for reaching the required cutting force and cutting heat are reduced, the production cost is lowered, and the production process is simplified.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of processing equipment of crankcase cover, more specifically, a kind of deformation electric control clamp for crankcase cover thin-walled part. BACKGROUND

[0002] Thin-walled parts are widely used in motorcycle, automobile crankcase cover and other structures. However, in order to obtain better mechanical properties, these parts are usually processed by using bulk materials, in which a large proportion of materials (usually more than 90%) are removed, and the original balance of initial internal stress is destroyed. In addition, the tool-workpiece contact area is severely plastically deformed under the action of high temperature, high pressure and high strain rate, and inevitably generates machining-induced residual stress. When the clamp is released, the residual stress is rebalanced, causing the deformation of the part. It is well known that shape distortion is the main reason for low yield of thin-walled parts, and has become a technical bottleneck for the manufacture of thin-walled parts. Deformation caused by scrap repair also increases production cost and reduces processing efficiency.

[0003] At present, most of the domestic research on reducing residual stress of thin-walled parts focuses on reducing cutting force and cutting heat or annealing before rough machining of thin-walled parts. Such methods require higher machining technology and higher requirements for tool performance and materials. There is no system and process equipment that relies on electric control clamp to adjust the displacement of workpiece between each machining process to reduce or eliminate the influence of residual stress on workpiece deformation. SUMMARY

[0004] Therefore, it is necessary to provide a deformation electric control clamp for crankcase cover thin-walled part to solve the above technical problems.

[0005] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0006] A deformation electric control clamp for crankcase cover thin-walled part, characterized in that the deformation electric control clamp for crankcase cover thin-walled part comprises a clamp base, a rotatable rotary bearing is arranged on the clamp base, an auxiliary device is arranged on the rotary bearing, the auxiliary device comprises a back-shaped fixed support, a pair of oppositely arranged electric control clamp mounting structures are arranged on the inner wall of the fixed support,

[0007] A pair of detachable electric control clamps are arranged on the electric control clamp mounting structures, a telescopic extrusion stud is arranged on the electric control clamp,

[0008] A pair of parallel arranged right angle plate structures are arranged on one of the electric control clamp mounting structures, and a plurality of eddy current displacement sensors are arranged on the right angle plate structures.

[0009] As a preferred embodiment of the present application, the fixture base comprises a plate-shaped base substrate, a head of the base substrate is provided with a rotating slot, the rotating slot is arranged perpendicular to the base substrate, a rotating bearing is arranged in the rotating slot, and a tail of the base substrate is provided with a positioning device, the positioning device is arranged perpendicular to the base substrate.

[0010] As a preferred embodiment of the present application, edges of the base substrate are provided with a plurality of substrate holes.

[0011] As a preferred embodiment of the present application, the electrically controlled fixture mounting structure comprises a plate-shaped main substrate and a pair of plate-shaped auxiliary substrates, the auxiliary substrates are arranged perpendicular to the main substrate, and the electrically controlled fixture is arranged on the auxiliary substrates.

[0012] As a preferred embodiment of the present application, the right-angle plate structure is provided with a plurality of linearly arranged sensor mounting holes, and the eddy current displacement sensors are arranged in the sensor mounting holes.

[0013] As a preferred embodiment of the present application, the mounting positions of the eddy current displacement sensors are beyond the mounting position of the electrically controlled fixture.

[0014] As a preferred embodiment of the present application, the number of the eddy current displacement sensors is 10, and the distance between adjacent two eddy current displacement sensors is 10 mm.

[0015] As a preferred embodiment of the present application, the rotating bearing, the electrically controlled fixture and the eddy current displacement sensors are connected to a PLC control platform through I / O lines.

[0016] The present application also discloses a machining method of a thin-wall crankcase cover, which is applied to the deforming electrically controlled fixture for the thin-wall crankcase cover.

[0017] In step S1, the thin-wall cover is installed on the positioning device and fastened by bolts.

[0018] In step S2, the electrically controlled fixture is started by the PLC control platform, and the electrically controlled fixture clamps the top of the thin-wall cover.

[0019] In step S3, the initial position of the eddy current displacement sensor is adjusted, the initial position is recorded by the PLC control platform, the numerical control machine tool is started, and the first process is performed on the thin-wall cover M.

[0020] Step S4, after the first process is completed, the electric control clamp is automatically loosened, the residual stress in the inside of the thin-walled box cover is released, the redistribution of the residual stress deforms the thin-walled box cover again, the eddy current displacement sensor detects the position of the thin-walled box cover again and transmits the feedback data to the PLC control platform, the PLC control platform calculates based on the received feedback data, readjusts the clamping force of the electric control clamp 3 and adjusts the position to balance the residual stress in the inside of the thin-walled box cover, and the numerical control machine tool is started again to perform the second process;

[0021] Step S5, repeat step S3 and step S4 until the working operation of the thin-walled box cover is completed.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] The present application provides a deformation electric control clamp for a thin-walled crankcase cover part, which directly adjusts the deformation of the thin-walled part, without the need for annealing and normalizing treatment of the thin-walled part in advance to improve the metal organization and performance, and reduces the high requirements for the material and performance of the tool to achieve the required cutting force and cutting heat, greatly reducing the production cost and simplifying the production process. In addition, the clamp is in full automatic control state during the machining process without manual intervention, and one person can control multiple equipment to work, improving the work efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the schemes in the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings described below are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0025] Figure 1 Flow chart of the processing method of the thin-walled crankcase cover part of the present application;

[0026] Figure 2 Schematic diagram of the three-dimensional structure of the deformation electric control clamp for the thin-walled crankcase cover part of the present application;

[0027] Figure 3 For Figure 1 Schematic diagram of the local structure of the deformation electric control clamp for the thin-walled crankcase cover part in the present application;

[0028] Figure 4 For Figure 2 Schematic diagram of the use of the deformation electric control clamp for the thin-walled crankcase cover part in the present application. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0030] like Figures 2 to 4 As shown, the deformation electronic control fixture for the thin-walled crankcase cover includes a fixture base 1, a rotatable rotary bearing 2 on the fixture base 1, an auxiliary device 5 on the rotary bearing 2, and an auxiliary device 5 including a U-shaped fixed bracket 5a. The inner wall of the fixed bracket 5a is provided with a pair of opposing electronic control fixture mounting structures 5b.

[0031] Each of the electrically controlled clamp mounting structures 5b is equipped with a pair of detachable electrically controlled clamps 3, and each electrically controlled clamp 3 is equipped with a retractable extrusion head 31.

[0032] It should be noted that the electrically controlled fixture 3 utilizes an external control signal for precise adjustment of the clamping force of the extrusion head 31. The fixture 3 incorporates a motor and a threaded screw structure to achieve the extrusion of the extrusion head 31. A pressure sensor is also included within the fixture 3, transmitting the real-time pressure of the extrusion head 31 to the PLC control platform, which will be further explained later. Alternatively, the electrically controlled fixture 3 can also be replaced by a CNC hydraulic head.

[0033] One of the electrical control fixture mounting structures 5b is provided with a pair of parallel right-angle plate structures 5c, and the right-angle plate structures 5c are provided with a number of eddy current displacement sensors 4.

[0034] The fixture base 1 includes a plate-shaped base plate 12. A rotating slot 11 is provided on the base plate 12, and the direction of the rotating slot 11 is perpendicular to the base plate 12. A rotating bearing 2 is disposed within the rotating slot 11. A positioning device 13 is provided at the tail end of the base plate 12, and the direction of the positioning device 13 is perpendicular to the base plate 12. Three boss mounting screw holes 131 are provided on the end face of the positioning device 13 for fixing the thin-walled box cover.

[0035] In addition, a groove 132 is provided in the middle of the positioning device 13, and the groove 132 is interference-fitted with the boss structure of the workpiece to be processed.

[0036] The base plate 12 has several base plate holes 121 on its edge. The base plate 12 can be fixed to the worktable of a CNC machine tool using the base plate holes 121 and bolts.

[0037] The electric control clamp mounting structure 5b comprises a plate-shaped main base plate 5b1 and a pair of plate-shaped auxiliary base plates 5b2, the setting direction of the auxiliary base plate 5b2 is perpendicular to the main base plate 5b1, and the electric control clamp 3 is arranged on the auxiliary base plate 5b2.

[0038] The right-angle plate structure 5c is provided with a plurality of linearly arranged sensor mounting holes 5c1, and the eddy current displacement sensor 4 is arranged in the sensor mounting hole 5c1.

[0039] The mounting positions of the eddy current displacement sensors 4 are all outside the mounting positions of the electric control clamp 3. The number of the eddy current displacement sensors 4 is 10. The distance between two adjacent eddy current displacement sensors 4 is 10 mm.

[0040] It should be noted that the rotary bearing 2, the electric control clamp 3 and the eddy current displacement sensor 4 are all connected with the PLC control platform through I / O lines.

[0041] As shown in Figure 1 The following describes the use process of the deformation electric control clamp for the thin-walled crankcase cover, comprising the following steps:

[0042] Step S1, the thin-walled cover M is arranged on the positioning device 13 and fastened by bolts;

[0043] Step S2, the electric control clamp 3 is started by the PLC control platform, and the electric control clamp 3 clamps the top of the thin-walled cover M;

[0044] Step S3, the initial position of the eddy current displacement sensor 4 is adjusted, specifically, the readings of the two groups of eddy current displacement sensors 4 are compared, and the angle of the rotary bearing 2 is adjusted, when the readings of the two groups of eddy current displacement sensors 4 are the same, the rotary bearing 2 stops rotating, at this time, the clamping plane of the electric control clamp 3 is parallel to the machining plane of the thin-walled cover M, and the initial position is recorded by the PLC control platform. Start the numerical control machine tool to process the thin-walled cover M, and perform the first process;

[0045] Step S4, after the first process is completed, the electric control clamp 3 is automatically released, the residual stress in the thin-walled cover M is released, the redistribution of the residual stress deforms the thin-walled cover M again, the eddy current displacement sensor 4 detects the position of the thin-walled cover M again, and feeds back the data to the PLC control platform, the PLC control platform calculates based on the received feedback data, adjusts the clamping force and position of the electric control clamp 3 to balance the residual stress in the thin-walled cover M. Start the numerical control machine tool again to perform the second process;

[0046] Step S5, the cycle is repeated until the machining of the thin-walled cover M is completed.

[0047] The step S4 is further described below.

[0048] When the eddy current displacement sensor 4 detects the position of the thin-walled box cover M again, the current position is fed back to the PLC control platform, and the PLC control platform calculates the displacement distance caused by the redistribution of residual stress by subtracting the initial position in step S3. The PLC control platform adjusts the clamping force of the electric clamp 3 and adjusts the position according to the displacement distance, so as to balance the residual stress in the thin-walled box cover M.

[0049] The electric clamp 3 adjusts the clamping force of the electric clamp 3 according to the data fed back by the two groups of eddy current displacement sensors 4, balances the residual stress in the thin-walled box cover M, and achieves the purpose of reducing the residual stress of the thin-walled part.

[0050] The displacement distance fed back by the eddy current displacement sensor 4 can be used to obtain the average residual stress in the vertical feed direction and the feed direction:

[0051] The cubic polynomial function of the residual stress of rough milling is as formula (1)-(2)

[0052] (1)

[0053] (2)

[0054] The cubic polynomial function of the residual stress of fine milling is as formula (3)-(4)

[0055] (3)

[0056] (4)

[0057] In the formula, is the residual stress in the vertical feed direction, is the residual stress in the feed direction, is the displacement distance of the workpiece fed back by different eddy current displacement sensors.

[0058] The functions of the average residual stress in the vertical feed direction and the feed direction are as formula (5)-(6)

[0059] (5)

[0060] (6)

[0061] In the formula, is the average residual stress in the vertical feed direction, is the average residual stress in the feed direction, and n is the number of eddy current displacement sensors.

[0062] The obtained is compared with The load output of the finite element model is connected to the finite element software Abaqus (Abaqus has built-in material aluminum, which has isotropy and linear elasticity. The C3D10 unit is used for meshing the part, and the grid size of the finite element model is 1mm) connected with the PLC control platform, and the deformation caused by residual stress in each process is calculated The results are output to the control system, so as to control the intelligent clamp device to clamp the workpiece and make it deform, so as to balance the residual stress in the workpiece. The deformation formula is as follows:

[0063] (7)

[0064] In the formula, represents the induced deformation of the electric control clamp on the workpiece for eliminating residual stress in the nth process,

[0065] represents the deformation of the nth process due to residual stress.

[0066] The deformation electric control clamp for the thin-walled part of the crankcase cover directly adjusts the deformation of the thin-walled part, without the need for annealing and normalizing treatment of the thin-walled part in advance to improve the metal organization and performance, and reduces the high requirements for the material and performance of the tool to achieve the required cutting force and cutting heat, greatly reduces the production cost, and simplifies the production process. In addition, the clamp is in a fully automatic control state during the machining process, without manual intervention, and can realize one-person control of multiple equipment for operation, improving the work efficiency.

[0067] Not limited to this, any changes or replacements not thought of through creative labor should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope defined in the claims.

Claims

1. A method of machining a thin-walled member of a crankcase cover, using a deformation electric control jig for a thin-walled member of a crankcase cover, characterized by, The method comprises the steps of: Step S1, mounting the thin-walled box cover (M) on the positioning device (13) and fastening it with bolts; Step S2, starting the electric control clamp (3) through the PLC control platform, and the electric control clamp (3) clamps the top of the thin-walled box cover (M); Step S3, adjusting the initial position of the eddy current displacement sensor (4), the PLC control platform records the initial position, starts the numerical control machine tool, and begins to process the thin-walled box cover (M) to perform the first process; Step S4, after the first process is completed, the electric control clamp (3) is automatically released, the residual stress in the interior of the thin-walled box cover (M) is released, the redistribution of the residual stress deforms the thin-walled box cover (M) again, the eddy current displacement sensor (4) detects the position of the thin-walled box cover (M) again and transmits feedback data to the PLC control platform, the PLC control platform calculates based on the received feedback data, readjusts the clamping force of the electric control clamp (3) and adjusts the position to balance the residual stress in the interior of the thin-walled box cover (M), and the numerical control machine tool is started again to perform the second process; Step S5, repeating steps S3 and S4 until the machining of the thin-walled box cover (M) is completed; Wherein, The deformed electric control clamp for the thin-walled box cover comprises a clamp base (1), a rotatable rotating bearing (2) is arranged on the clamp base (1), an auxiliary device (5) is arranged on the rotating bearing (2), the auxiliary device (5) comprises a back-shaped fixed support (5a), a pair of oppositely arranged electric control clamp mounting structures (5b) are arranged on the inner wall of the fixed support (5a), A pair of detachable electric control clamps (3) are arranged on the electric control clamp mounting structure (5b), a telescopic extrusion column head (31) is arranged on the electric control clamp (3), One of the electric control clamp mounting structures (5b) is provided with a pair of parallel arranged right angle plate structures (5c), and a plurality of eddy current displacement sensors (4) are arranged on the right angle plate structure (5c).

2. The method of processing a thin-walled crankcase cover part according to claim 1, characterized in that The clamp base (1) comprises a plate-shaped base substrate (12), a rotating slot (11) is arranged at the head of the base substrate (12), the arrangement direction of the rotating slot (11) is perpendicular to the base substrate (12), the rotating bearing (2) is arranged in the rotating slot (11), and a positioning device (13) is arranged at the tail of the base substrate (12), and the arrangement direction of the positioning device (13) is perpendicular to the base substrate (12).

3. The method of processing a thin-walled crankcase cover part according to claim 2, characterized in that A plurality of base substrate holes (121) are arranged on the edge of the base substrate (12).

4. The machining method of the thin-walled box cover according to claim 1, wherein The electric control clamp mounting structure (5b) comprises a plate-shaped main base plate (5b1) and a pair of plate-shaped auxiliary base plates (5b2), the arrangement direction of the auxiliary base plate (5b2) is perpendicular to the main base plate (5b1), and the electric control clamp (3) is arranged on the auxiliary base plate (5b2).

5. The method of processing a thin walled crankcase cover part according to claim 1, characterized in that The right-angle plate structure (5c) is provided with a plurality of linearly arranged sensor mounting holes (5c1), and the eddy current displacement sensors (4) are mounted in the sensor mounting holes (5c1).

6. The method of processing a thin walled crankcase cover part according to claim 5, characterized in that The mounting positions of the eddy current displacement sensors (4) are beyond the mounting positions of the electric control clamps (3).

7. The method of processing a thin walled crankcase cover part according to claim 6, characterized in that The number of the eddy current displacement sensors (4) is 10, and the distance between two adjacent eddy current displacement sensors (4) is 10 mm.

8. The method of claim 1, wherein, The rotary bearing (2), the electric control clamp (3) and the eddy current displacement sensor (4) are connected with a PLC control platform through I / O lines.

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