Device and method for measuring parallelism of mold cavity in electric spark machining process

Abstract

The invention discloses a device and a method for measuring the parallelism of a mold cavity in an electric spark machining process. The device comprises a base, a stand column, a Y-direction mechanism, a Z-direction mechanism, an ohmmeter and a measuring rod, the lower ends of the columns are fixed on the base; the Y-direction mechanism is rotationally installed at the upper end of the stand column and used for achieving angle adjustment of the measuring rod on the template. The Z-direction mechanism is installed on the Y-direction mechanism, and the measuring rod is installed on the Z-direction mechanism. The Y-direction mechanism is used for adjusting the position of the measuring rod in the horizontal direction; the Z-direction mechanism is used for adjusting the position of the measuring rod in the vertical direction and measuring the parallelism of the template; and the ohmmeter is connected and conducted with the measuring rod and the template through wires. Compared with the prior art, in the mold template electric spark machining process, under the condition that electric spark engine oil in the oil groove is not pumped out, detection of the parallelism of the bottom face of the mold cavity is completed, working hours can be greatly shortened, the working efficiency is improved, and the mold manufacturing period is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of parallelism measurement, and in particular to a device and method for measuring the parallelism of a mold cavity during electric spark machining. Background Art

[0002] In the process of injection mold manufacturing, complex mold cavities need to be processed by electrospark forming. During the processing, it is sometimes necessary to detect the parallelism between the bottom surface of the mold cavity and the parting surface of the template to ensure that the manufacturing accuracy of the mold meets the design requirements. The existing detection method is generally to use a dial indicator for detection. Since the dial indicator cannot be used in electrospark oil, the electrospark oil in the oil tank needs to be extracted before detection. If the test result does not meet the requirements, it is necessary to add electrospark oil to the oil tank to continue the molding process. This is very inconvenient and greatly increases the working hours. Especially when there are multiple different cavity bottom surfaces on the mold template that need to be detected, the electrospark oil needs to be extracted multiple times, which prolongs the manufacturing cycle of the mold and affects work efficiency.

[0003] In the prior art, there is no technical enlightenment on the device for measuring the parallelism of the mold cavity during the electrospark machining process in the published literature. Summary of the invention

[0004] The purpose of the present invention is to provide a device and method for measuring the parallelism of a mold cavity during electrospark machining, so as to solve the problem in the prior art that the parallelism of the bottom surface of the mold cavity needs to be measured by extracting electrospark machine oil.

[0005] To achieve the above-mentioned purpose, the technical scheme of the present invention is as follows: a device for measuring the parallelism of a mold cavity during electrospark machining, comprising a base, a column, a Y-direction mechanism, a Z-direction mechanism, an ohmmeter and a measuring rod; the lower end of the column is fixed on the base; the upper end of the column is rotatably mounted with a Y-direction mechanism, and the Y-direction mechanism takes the central axis of the column as the rotation center, thereby realizing the angle adjustment of the measuring rod on the template; the Z-direction mechanism is mounted on the Y-direction mechanism, and the measuring rod is mounted on the Z-direction mechanism; the Y-direction mechanism is used to realize the position adjustment of the measuring rod in the horizontal direction; the Z-direction mechanism is used to realize the position adjustment of the measuring rod in the vertical direction and the measurement of the parallelism of the template; the ohmmeter is connected to the measuring rod and the template through a wire and is turned on, and when the end of the measuring rod contacts the upper surface of the template, the ohmmeter displays current.

[0006] Furthermore, the Y-axis mechanism includes a connecting plate, a guide rod, a slide plate, a lead screw and a handle; one end of the connecting plate is rotatably connected to the upper end of the column, and the connecting plate can rotate at any angle in the horizontal plane with the axis of the column as the rotation center; the first baffle and the second baffle are provided at both ends of the connecting plate; the two ends of the guide rod are respectively fixedly connected to the first baffle and the second baffle; the two ends of the lead screw are rotatably connected to the first baffle and the second baffle; the handle is fixedly installed on the end of the lead screw away from the column; a threaded hole and a light hole are opened on the upper part of the slide plate; the slide plate cooperates with the thread on the lead screw through the threaded hole, and the lead screw rotates, thereby driving the slide plate to move; the slide plate is slidably connected to the guide rod through the light hole.

[0007] Furthermore, the Z-axis mechanism includes a micrometer, a guide slider, a slider, a fixed iron sheet, and an insulating rubber sleeve; the micrometer is fixedly mounted on the slider; the micrometer screw of the micrometer is fixedly connected to the slider, the guide slider is fixedly mounted on the slider, and the slider is slidably connected to the guide slider; the measuring rod is fixedly connected to the side of the slider through a fixed iron sheet and the measuring rod and the slider are insulated by an insulating rubber sleeve.

[0008] Furthermore, the base is magnetic and can be attracted to the workbench of the machine tool.

[0009] Furthermore, the measuring end of the measuring rod is a spherical surface with a diameter of 0.5 mm.

[0010] A method for measuring mold cavity parallelism during electrospark machining, comprising the following steps:

[0011] S1. Place the parallelism measuring device on the workbench of the EDM machine and adjust the micrometer to read 0.

[0012] S2, determining the number of points to be tested on the bottom surface of the template cavity;

[0013] S3, determining the position of each test point on the bottom surface of the template cavity;

[0014] S4, rotate the connecting plate to make the measuring rod rotate in the horizontal plane;

[0015] S5. Rotate the handle on the lead screw to move the measuring rod along the Y direction;

[0016] S6. When the measuring end of the measuring rod is adjusted to just above the test point on the bottom surface of the cavity, stop rotating the connecting plate and the handle;

[0017] S7. Turn the micrometer to move the measuring rod in the Z direction. When the measuring end of the measuring rod touches the test point on the bottom surface of the cavity, the ohmmeter will show that current is passing through. At this time, record the scale value Z1 of the micrometer.

[0018] S8. Use the same method to obtain the scale values ​​of the micrometer corresponding to other test points on the bottom surface of the cavity: Z2, Z3, ... Z n ;

[0019] S9, parallelism calculation;

[0020] S10. After the measurement is completed, rotate the micrometer to return it to zero, remove the measuring device from the oil tank, and complete the measurement of the parallelism between the bottom surface of the template cavity and the template reference surface.

[0021] Furthermore, the parallelism is calculated as:

[0022] Parallelism = max{Z1-Z0, Z2-Z0, ... Z n -Z0}-min{Z1-Z0,Z2-Z0,……Z n -Z0},

[0023] =(Z max -Z0)-(Z min -Z0)

[0024] =Z max -Z min

[0025] Where Z0 represents the reading value of any test point on the template reference surface in the Z direction, n Indicates the reading value of the nth test point on the bottom surface of the cavity measured by the micrometer, Z n -Z0 represents the length between the nth test point on the bottom surface of the cavity and the test point on the template reference surface in the Z direction, max{Z1-Z0,Z2-Z0,……Z n -Z0} represents the maximum value among these n length values, min{Z1-Z0,Z2-Z0,...Z n -Z0} represents the minimum value among these n length values, Z max It represents the maximum value of the readings of n test points on the bottom surface of the cavity measured by the micrometer, Z min It indicates the minimum value of the readings of the micrometer at n test points on the bottom surface of the cavity; Z max -Z min It is the measured value of the parallelism between the bottom surface of the cavity and the reference surface of the template.

[0026] Furthermore, the number of points to be tested on the bottom surface of the template cavity is determined to be no less than 3.

[0027] Compared with the prior art, the present invention has the following significant advantages:

[0028] 1. When the electric spark forming machine tool processes the mold cavity, the electric spark machine oil in the oil tank does not need to be extracted. The parallelism between the bottom surface of the mold cavity and the parting surface of the template can be detected by the present invention, which can greatly reduce working hours, improve work efficiency, and shorten the manufacturing cycle of the mold;

[0029] 2. The present invention can obtain the parallelism between the bottom surface of the mold cavity and the parting surface of the template through the difference between the maximum and minimum values ​​of the micrometer reading, and the effect is intuitive;

[0030] 3. The device of the present invention has a simple structure and provides a simple and convenient operation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of the mold cavity parallelism measuring device during the electrospark machining process of the present invention.

[0032] Figure 2 The invention discloses a Y-axis mechanism structure schematic diagram of a device for measuring parallelism of a mold cavity during an electrospark machining process.

[0033] Figure 3 The invention discloses a schematic diagram of the Z-direction structure of a device for measuring parallelism of a mold cavity during an electrospark machining process.

[0034] In the figure, 1. base, 2. column, 3. Y-axis mechanism, 4. Z-axis mechanism, 5. ohmmeter, 6. template, 7. oil tank, 8. EDM oil, 9. electrode, 10. spindle head, 11. nut, 12. connecting plate, 13. slide plate, 14. lead screw, 15. handle, 16. first baffle, 17. second baffle, 18. guide rod, 19. limit plate, 20. first wire, 21. second wire, 22. micrometer, 23. micrometer screw, 24. guide slide block, 25. slide block, 26. fixed iron sheet, 27. insulating rubber sleeve, 28. measuring rod. DETAILED DESCRIPTION

[0035] The following is combined with Figure 1-3 The present invention is described in detail with reference to the accompanying drawings and embodiments.

[0036] In order to more clearly understand the technical essence and beneficial effects of the present invention, the applicant will explain the specific implementation methods of the present invention in detail below in conjunction with the accompanying drawings. However, the description of the embodiments is not a limitation of the present invention. Any equivalent changes made based on the concept of the present invention that are merely formal but not substantial should be regarded as within the scope of the technical solution of the present invention and be protected.

[0037] See also Figure 1-3, the present invention provides a technical solution: a device for measuring the parallelism of a mold cavity during an electrospark machining process, comprising a base 1, a column 2, a Y-direction mechanism 3, a Z-direction mechanism 4, an ohmmeter 5 and a measuring rod 28;

[0038] The base 1 is magnetic and can be attached to the machine tool workbench;

[0039] The column 2 is a stepped shaft with a diameter at the upper end smaller than that at the lower end. The lower end of the column 2 is fixed on the base 1;

[0040] like Figure 2 As shown, the Y-axis mechanism 3 includes a connecting plate 12, a guide rod 18, a slide plate 13, a lead screw 14, and a handle 15;

[0041] One end of the connecting plate 12 is rotatably connected to the small diameter section at the upper end of the column 2, and the connecting plate 12 can rotate at any angle in the horizontal plane with the axis of the column 2 as the rotation center. The first baffle 16 and the second baffle 17 are provided at both ends of the connecting plate 12. The two ends of the guide rod 18 are respectively fixedly connected to the first baffle 16 and the second baffle 17 of the connecting plate 12. The nut 11 is threadedly connected to the end of the lead screw 14, which is used to limit the direction of the axis of the lead screw 14; the two ends of the lead screw 14 are rotatably connected to the first baffle 16 and the second baffle 17 of the connecting plate 12. The handle 15 is installed at the end of the lead screw 14 that is far away from the column 2. The lead screw 14 is fixedly connected to the handle 15. Rotating the handle 15 allows the lead screw 14 to rotate at any angle with its axis as the rotation center.

[0042] A threaded hole and a light hole are provided on the upper part of the slide plate 13. The slide plate 13 cooperates with the thread on the lead screw 14 through the threaded hole, and the lead screw 14 rotates to drive the slide plate 13 to move. The slide plate 13 is slidably connected with the guide rod 18 through the light hole.

[0043] A limit plate 19 is provided at the bottom of the slide plate 13 for mounting a micrometer 22;

[0044] like Figure 3 As shown, the Z-direction mechanism 4 includes a micrometer 22, a guide slider 24, a slider 25, a fixed iron sheet 26, and an insulating rubber sleeve 27;

[0045] The micrometer 22 is fixedly mounted on the limit plate 19 of the slide 13. The micrometer screw 23 of the micrometer 22 is fixedly connected to the slider 25, the guide slider 24 is fixedly mounted on the slide 13, and the slider 25 is slidably connected to the guide slider 24. The measuring rod 28 is fixedly connected to the side of the slider 25 through the fixed iron sheet 26, and the measuring rod 28 and the slider 25 are insulated by an insulating rubber sleeve. The measuring end (end) of the measuring rod 28 is a spherical surface with a diameter of 0.5 mm.

[0046] The ohmmeter 5 is hung on the oil tank (or the ohmmeter 5 is placed at any visible position on the machine tool).

[0047] The positive pole of the ohmmeter 5 is connected to the measuring rod 28 through the first wire 20 and is in conduction. The negative pole of the ohmmeter 5 is connected to the template 6 (i.e., the workpiece) through the second wire 21 and is in conduction;

[0048] The present invention also discloses a method for measuring the parallelism of a mold cavity during an electrospark machining process. First, the spindle head 10 drives the electrode 9 to move upward in the Z direction, and then the spindle head 10 drives the electrode 9 to move in the positive direction of the Y direction to leave a measuring space for the cavity to be measured, and then the parallelism of the bottom surface of the mold cavity and the parting surface of the template is detected. The specific steps are as follows:

[0049] S1. Place the parallelism measuring device on the workbench of the EDM machine and adjust the micrometer 22 to read 0.

[0050] S2, determining the number of points to be tested on the bottom surface of the template cavity;

[0051] S3, determining the position of each test point on the bottom surface of the template cavity;

[0052] S4, rotating the connecting plate 12 to rotate the measuring rod 28 in the horizontal plane;

[0053] S5, rotating the handle 15 on the lead screw 14 to move the measuring rod 28 along the Y direction;

[0054] S6. When the measuring end of the measuring rod 28 is adjusted to be directly above the test point on the bottom surface of the cavity, the connecting plate 12 and the handle 15 are stopped from rotating;

[0055] S7, rotate the micrometer 22 to move the measuring rod 28 along the Z direction. When the measuring end of the measuring rod 28 contacts the test point on the bottom surface of the cavity, the ohmmeter 5 will show that current is passing. At this time, record the scale value Z1 of the micrometer 22;

[0056] S8. The same method is used to obtain the scale values ​​of the micrometer 22 corresponding to other test points on the bottom surface of the cavity, which are Z2, Z3, ... Z n ;

[0057] S9, parallelism calculation, parallelism = max{Z1-Z0, Z2-Z0, ... Z n -Z0}-min{Z1-Z0,Z2-Z0,……Z n -Z0},

[0058] =(Z max -Z0)-(Z min -Z0)

[0059] =Z max -Z min

[0060] Where Z0 represents the reading value of any test point on the reference surface of template 6 in the Z direction, n Indicates the reading value of the nth test point on the bottom surface of the cavity measured by the micrometer, Z n -Z0 represents the length between the nth test point on the bottom surface of the cavity and the test point on the reference surface of template 6 in the Z direction, max{Z1-Z0,Z2-Z0,……Z n -Z0} represents the maximum value among these n length values, min{Z1-Z0,Z2-Z0,...Z n -Z0} represents the minimum value among these n length values, Z max It represents the maximum value of the readings of n test points on the bottom surface of the cavity measured by the micrometer, Z min It indicates the minimum value of the micrometer readings at n test points on the bottom surface of the cavity.

[0061] Z max -Z min It is the measured value of the parallelism between the bottom surface of the cavity and the reference surface of the template 6.

[0062] S10, after the measurement is completed, the micrometer 22 is rotated to return the micrometer 22 to zero, and the measuring device is taken out from the oil tank 7 to complete the measurement of the parallelism between the bottom surface of the cavity and the reference surface of the template 6.

[0063] The above technical solution can quickly detect the parallelism between the bottom surface of the mold template cavity and the reference surface, and the measurement accuracy reaches 0.01mm.

[0064] In the present invention, the number of points to be tested on the bottom surface of the template cavity is determined to be no less than 3. The positions of the points to be tested on the bottom surface of the template cavity cannot be at the rounded corners between the bottom surface and the side wall. When the detection device is placed on the workbench of the EDM machine tool for detection, it is not necessary to extract the EDM machine oil 8 in the oil tank 7.

[0065] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents, and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for measuring the parallelism of a mold cavity during electrospark machining, characterized in that: The invention comprises a base (1), a column (2), a Y-direction mechanism (3), a Z-direction mechanism (4), an ohmmeter (5) and a measuring rod (28); the lower end of the column (2) is fixed on the base (1); the upper end of the column (2) is rotatably mounted with a Y-direction mechanism (3), the Y-direction mechanism (3) takes the central axis of the column (2) as the rotation center, thereby realizing the angle adjustment of the measuring rod (28) on the template (6); the Z-direction mechanism (4) is mounted on the Y-direction mechanism (3), and the measuring rod (28) is mounted on the Z-direction mechanism (4); the Y-direction mechanism (3) is used to realize the position adjustment of the measuring rod (28) in the horizontal direction; the Z-direction mechanism (4) is used to realize the position adjustment of the measuring rod (28) in the vertical direction and the measurement of the parallelism of the template; the ohmmeter (5) is connected to the measuring rod and the template (6) through a wire and is turned on; when the end of the measuring rod (28) contacts the upper surface of the template (6), the ohmmeter (5) displays current.

2. According to claim 1, a device for measuring parallelism of mold cavity during electrospark machining, characterized in that: The Y-direction mechanism (3) comprises a connecting plate (12), a guide rod (18), a slide plate (13), a lead screw (14) and a handle (15); one end of the connecting plate (12) is rotatably connected to the upper end of the column (2), and the connecting plate (12) can rotate at any angle in a horizontal plane with the axis of the column (2) as the rotation center; a first baffle (16) and a second baffle (17) are arranged at both ends of the connecting plate (12); both ends of the guide rod (18) are fixedly connected to the first baffle (16) and the second baffle (17) respectively. and the second baffle (17); the two ends of the lead screw (14) are rotatably connected to the first baffle (16) and the second baffle (17); the end of the lead screw (14) away from the column (2) is fixedly installed with a handle (15); a threaded hole and a light hole are opened on the upper part of the slide plate (13); the slide plate (13) cooperates with the thread on the lead screw (14) through the threaded hole, and the lead screw (14) rotates, thereby driving the slide plate (13) to move; the slide plate (13) is slidably connected to the guide rod (18) through the light hole.

3. The device for measuring mold cavity parallelism during electrospark machining according to claim 1, characterized in that: The Z-direction mechanism (4) comprises a micrometer (22), a guide slider (24), a slider (25), a fixed iron sheet (26), and an insulating rubber sleeve (27); The micrometer (22) is fixedly mounted on the slide plate; the micrometer screw (23) of the micrometer (22) is fixedly connected to the slider (25); the guide slider (24) is fixedly mounted on the slide plate (13); the slider (25) is slidably connected to the guide slider (24); the measuring rod (28) is fixedly connected to the side of the slider (25) via a fixed iron sheet (26); and the measuring rod (28) and the slider (25) are insulated via an insulating rubber sleeve.

4. The device for measuring mold cavity parallelism during electrospark machining according to claim 1, characterized in that: The base is magnetic and is attracted to the working table of the machine tool.

5. The device for measuring mold cavity parallelism during electrospark machining according to claim 1, characterized in that: The measuring end of the measuring rod is a spherical surface with a diameter of 0.5 mm.

6. A method for measuring the parallelism of a mold cavity during electrospark machining, applicable to the parallelism measuring device according to any one of claims 1 to 5, characterized in that: include: S1. Place the parallelism measuring device on the workbench of the EDM machine and adjust the micrometer to read 0. S2, determining the number of points to be tested on the bottom surface of the template cavity; S3, determining the position of each test point on the bottom surface of the template cavity; S4, rotate the connecting plate to make the measuring rod rotate in the horizontal plane; S5. Rotate the handle on the lead screw to move the measuring rod along the Y direction; S6. When the measuring end of the measuring rod is adjusted to just above the test point on the bottom surface of the cavity, stop rotating the connecting plate and the handle; S7. Turn the micrometer to move the measuring rod in the Z direction. When the measuring end of the measuring rod touches the test point on the bottom surface of the cavity, the ohmmeter will show that current is passing through. At this time, record the scale value Z1 of the micrometer. S8. Use the same method to obtain the scale values ​​of the micrometer corresponding to other test points on the bottom surface of the cavity: Z2, Z3, ... Z n ; S9, parallelism calculation; S10. After the measurement is completed, rotate the micrometer to return it to zero, remove the measuring device from the oil tank, and complete the measurement of the parallelism between the bottom surface of the template cavity and the template reference surface.

7. The method for measuring mold cavity parallelism during electrospark machining according to claim 6, characterized in that: The calculation of parallelism is: Parallelism = max{Z1-Z0,Z2-Z0,……Z n -Z0}-min{Z1-Z0,Z2-Z0,……Z n -Z0}, =(From max -Z0)-(Z min -Z0) =Z max -WITH min Where Z0 represents the reading value of any test point on the template reference surface in the Z direction, Z n Indicates the reading value of the nth test point on the bottom surface of the cavity measured by the micrometer, Z n -Z0 represents the length between the nth test point on the bottom surface of the cavity and the test point on the template reference surface in the Z direction, max{Z1-Z0,Z2-Z0,……Z n -Z0} represents the maximum value among these n length values, min{Z1-Z0,Z2-Z0,...Z n -Z0} represents the minimum value among these n length values, Z max It represents the maximum value of the readings of n test points on the bottom surface of the cavity measured by the micrometer, Z min It indicates the minimum value of the reading of the micrometer at n test points on the bottom surface of the cavity; Z max -Z min It is the measured value of the parallelism between the bottom surface of the cavity and the reference surface of the template.

8. The method for measuring mold cavity parallelism during electrospark machining according to claim 6, characterized in that: The number of points to be tested on the bottom surface of the template cavity is determined to be no less than 3.

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