Electromagnetic relay electromagnetic attraction test method and positioning clamp

Abstract

The application discloses a kind of electromagnetic relay electromagnetic attraction test method and positioning fixture, the method is positioned by positioning fixture to the electromagnetic part of the electromagnetic relay to be measured, the clearance between armature and yoke of the electromagnetic part of the electromagnetic relay to be measured is positioned in the clearance range required by the electromagnetic relay to be measured;Electromagnetic attraction is generated by the coil of electromagnetic part to load excitation, and armature is operated, the excitation value corresponding to the moment of armature operation is compared with threshold value gradually increasing from small by coil loading excitation, meets threshold value requirement, and the electromagnetic attraction of the electromagnetic part of the electromagnetic relay to be measured meets the requirement.The electromagnetic attraction test method used in the present application positions the electromagnetic part of the electromagnetic relay to be tested, and the clearance between armature and yoke is the clearance required by the product, the force tested is more in line with actual production, and whether the electromagnetic attraction of magnetic circuit part meets the requirement of final product can be effectively judged.

Description

Technical Field

[0001] This invention belongs to the field of electrical equipment technology, specifically relating to a method for testing the electromagnetic attraction force of an electromagnetic relay and a positioning fixture. Background Technology

[0002] Electromagnetic relays are one of the fundamental electromechanical components in many automated, remote-controlled, and communication instruments. Their operating principle involves current flowing through the coil, generating magnetic flux in the iron core, which is then magnetized. The armature, under the influence of electromagnetic attraction, overcomes the reaction force to complete the relay's operation. The initial voltage value of the relay is a crucial performance indicator; therefore, relay manufacturers test the electromagnetic attraction during the production process of the relay's magnetic circuit.

[0003] The traditional testing method involves applying a fixed voltage to both ends of the coil in the magnetic circuit section, causing the armature to close under electromagnetic attraction, i.e., the gap is approximately zero. Then, a force gauge is used to test the other end of the armature until the force required to open the armature is reached. If this force is greater than the lower limit of the process requirement, the magnetic circuit section is considered qualified and can proceed to the next step.

[0004] As can be seen from the above, although the traditional testing method is convenient, the force tested is actually the holding force when the armature is closed, which indirectly characterizes the electromagnetic attraction. This holding force is related to the electromagnetic attraction, the fit between the armature and the yoke, and the assembly tolerances. Furthermore, the parameters measured manually with a handheld force gauge will also have some errors. Therefore, using this test value to determine whether the magnetic circuit part can pass the next process is not very accurate. Summary of the Invention

[0005] The purpose of this invention is to provide a method for testing the electromagnetic attraction force of an electromagnetic relay. This method provides more accurate test results and can effectively determine whether the electromagnetic strength of the magnetic circuit meets the requirements of the final product.

[0006] Therefore, the electromagnetic attraction force testing method for electromagnetic relays provided by the present invention positions the electromagnetic part of the electromagnetic relay under test using a positioning fixture. The positioning fixture positions the gap between the armature and the yoke of the electromagnetic part of the electromagnetic relay under test within the required gap range of the electromagnetic relay under test. An excitation is applied to the coil of the electromagnetic part to generate an electromagnetic attraction force that causes the armature to move. The excitation applied to the coil is gradually increased from small to large. The excitation value corresponding to the instant of armature movement is compared with a threshold value. If the threshold value is met, the electromagnetic attraction force of the electromagnetic part of the electromagnetic relay under test meets the requirements.

[0007] A second objective of this invention is to provide a positioning fixture used for positioning the electromagnetic part of an electromagnetic relay under test during testing of the electromagnetic attraction force of the electromagnetic part, comprising:

[0008] The first positioning block is configured with a positioning surface and a positioning gap;

[0009] The second positioning block is equipped with a yoke positioning groove;

[0010] Third positioning block;

[0011] Armature positioning block;

[0012] During testing, the electromagnetic part of the electromagnetic relay under test is placed on the positioning surface. The yoke positioning groove positions the yoke. The bottom ends of the third positioning block and the armature positioning block are respectively assembled in the positioning gap, and the bottom end of the armature positioning block can be detachably contacted with the third positioning block. Adjusting the position height of the third positioning block in the positioning gap changes the height of the top of the armature positioning block extending out of the positioning surface, thus affecting the armature and adjusting the gap between the armature and the yoke; or adjusting the distance between the third positioning block and the armature positioning block changes the height of the top of the armature positioning block extending out of the positioning surface, thus affecting the armature and adjusting the gap between the armature and the yoke. The gap between the armature and the yoke is positioned within the gap range required by the electromagnetic relay under test.

[0013] In some embodiments, the positioning fixture provided by the present invention further includes a spring for providing a holding force, the spring being obliquely mounted on the positioning surface; during testing, the armature of the electromagnetic part of the electromagnetic relay under test is subjected to a downward force by the spring.

[0014] In some implementations, the force provided by the reed is equal to the initial force provided by the reset spring required by the electromagnetic relay under test.

[0015] In some embodiments, the spacing of the yoke positioning slots is the yoke size of the electromagnetic part of the electromagnetic relay under test plus 0.01 mm.

[0016] Compared to traditional electromagnetic attraction force testing methods, which test the holding force (which is affected by many factors and can only partially characterize electromagnetic attraction force), the electromagnetic attraction force testing method used in this invention positions the electromagnetic part of the electromagnetic relay under test and ensures that the gap between the armature and yoke is the gap required by the product. The tested force is more closely related to actual production, effectively determining whether the electromagnetic attraction force of the magnetic circuit meets the requirements of the final product. Furthermore, this testing method is simple, low-cost, and can be used by most manufacturers, thus having broad application value. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0018] Figure 1 This is a schematic diagram of the positioning fixture described in this invention;

[0019] Figure 2-3 for Figure 1 A magnified view of a portion of the image;

[0020] Figure 4 This is a side view of the positioning fixture described in this invention;

[0021] Figure 5 This is a schematic diagram of the assembly of the positioning fixture provided by the present invention with the electromagnetic part of the electromagnetic relay to be tested.

[0022] Figure 6 This is a schematic diagram of the electromagnetic component. Detailed Implementation

[0023] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0024] This invention provides an electromagnetic attraction force testing method for testing the electromagnetic attraction force of the electromagnetic part of an electromagnetic relay. It can accurately determine whether the electromagnetic attraction force of the magnetic circuit part meets the production requirements and thus switch to the next production step. The method is simple and low in cost.

[0025] In this test method, the electromagnetic part 7 of the electromagnetic relay under test is mounted on a positioning fixture for positioning. The positioning fixture positions the gap between the armature and yoke of the electromagnetic part of the electromagnetic relay under test within the required gap range. An excitation is applied to the coil of the electromagnetic part to generate an electromagnetic attraction force that causes the armature to move. The excitation applied to the coil is gradually increased from small to large. The excitation value corresponding to the instantaneous movement of the armature is compared with the threshold value. If the threshold requirement is met, the electromagnetic attraction force of the electromagnetic part of the electromagnetic relay under test meets the requirements.

[0026] The testing principle of this method is based on the electromagnetic attraction formula:

[0027]

[0028] Where: IN - magnetomotive force of the coil; Gm -The total magnetic permeability of the electromagnet; -Working air gap;

[0029] As shown in the above formula, the electromagnetic attraction generated by the coil is related to the coil's magnetomotive force (IN), the product's structure, and the working air gap, i.e., the distance between the yoke end and the armature end. Since the number of turns (N) of the coil is fixed, and the coil's resistance value R is also fixed, the magnitude of the electromagnetic attraction varies with the applied voltage V and the working air gap. When the working air gap value and the various reaction forces of the relay (such as the spring force of the return spring on the armature) are fixed, the magnitude of the voltage V when the armature actuates can characterize the magnitude of the electromagnetic attraction of that magnetic circuit. The magnitude of the electromagnetic attraction is one of the important factors affecting whether the final electromagnetic relay product can work normally. Therefore, it is of great significance to test the electromagnetic attraction of the electromagnetic part in advance during the assembly of the whole machine to ensure that it can meet the product requirements.

[0030] This testing method fixes the electromagnetic components of the electromagnetic relay under test, and the gap between the armature 71 and the yoke 72 is fixed within the required gap range for the relay. In this state, the magnitude of the voltage applied to the coil 73 to actuate the armature determines whether the magnetic circuit meets the final product requirements. If the product requirements are met after testing with this method, the next process can proceed, ensuring the accuracy of the sequence transition and reducing rework caused by this issue.

[0031] Please refer to Figure 1-6 The positioning fixture in this disclosure includes a first positioning block 1 configured with a positioning surface 11 and a positioning gap 12, a second positioning block 2 configured with a yoke positioning groove 21, a third positioning block 3, and an armature positioning block 4. During testing, the electromagnetic part of the electromagnetic relay under test is placed on the positioning surface 11, the yoke positioning groove 21 positions the yoke, the bottom ends of the third positioning block 3 and the armature positioning block 4 are respectively assembled in the positioning gap 11, and the bottom end of the armature positioning block 4 can be detachably contacted with the third positioning block 3. The initial position of the bottom end of the armature positioning block 4 is in contact with the third positioning block 3. By adjusting the position of the third positioning block 3, it acts on the bottom end of the armature positioning block 4, generating an upward force that changes the size of the positioning surface 11 at the top extension of the armature positioning block 4, allowing the armature to move closer to or away from the yoke, thereby adjusting the gap between the two.

[0032] Alternatively, by placing a plug 9 between the bottom ends of the third positioning block 3 and the armature positioning block 4, the distance between the third positioning block 3 and the armature positioning block 4 is changed, thereby changing the size of the positioning surface 11 at the top extension of the armature positioning block 4, so that the armature moves closer to or further away from the yoke, thus achieving the gap adjustment between the two.

[0033] The armature gap positioning is achieved by inserting an armature positioning block (made of zinc-copper alloy) and a plug into the gap positioning position to adjust the gap between the armature and the yoke. Different fixed-size plugs are used depending on the type of relay, such as 0.1 to 0.5 mm.

[0034] In this disclosure, the first positioning block 1 is configured to include a positioning surface 11, a positioning gap 12, a first positioning block A13 and a first positioning block B14, the positioning gap 12 is formed between the first positioning block A13 and the first positioning block B14, and the positioning surface 11 connects the first positioning block A13 and the first positioning block B14.

[0035] The second positioning block 2 is configured including a second positioning block A22 and a second positioning block B23, with a yoke positioning groove 21 formed between the second positioning blocks A22 and B23. The second positioning blocks A22 and B23 are respectively mounted on the positioning surface 11 by screws. The width of the yoke positioning groove 21 can be adjusted by adjusting the screws to meet the testing requirements of electromagnetic components of different sizes. The width of the yoke positioning groove 21 is designed based on the product yoke size plus 0.01mm to ensure that the yoke does not wobble after installation, thus ensuring the accuracy of the test results.

[0036] In this disclosure, the ends of the second positioning block A22 and the second positioning block B23 are respectively provided with adjustment holes for the assembly of the adjustment rod 6. The cooperation between the screw and the adjustment rod 6 realizes the width adjustment of the yoke positioning groove 21.

[0037] The third positioning block 3 is locked and assembled within the positioning gap 12 by the locking member 8. The first positioning block A13 has multiple mounting holes for assembling the locking member 8. The locking member 8 is assembled into the mounting holes at different positions to adjust the position of the third positioning block 3; alternatively, the mounting holes can be elongated, allowing the locking member 8 to slide up and down to adjust the position of the third positioning block 3. The locking member 8 can be a bolt, screw, nut, etc., and the assembly configuration is a matching threaded hole, allowing position adjustment by tightening / loosening.

[0038] To improve the accuracy of the test results, the positioning fixture of this disclosure is also equipped with a spring 5 for providing a holding force, which is obliquely mounted on the positioning surface 11. During the test, the armature of the electromagnetic part of the electromagnetic relay under test is subjected to a downward force by the spring 5, the magnitude of which can be set according to the test requirements. However, to ensure the accuracy of the results, this disclosure sets the magnitude of this force to be equal to the initial force provided by the reset spring required by the electromagnetic relay under test.

[0039] In this disclosure, the reed 5 uses stainless steel or tin bronze with a thickness of (0.05 to 0.2) mm, depending on the type of relay; the reaction force of the reed can be determined by adjusting the angle within (30 to 60) degrees, and the adjustment range of the reaction force is (5 to 50) mN.

[0040] During the test, the method for reading the electromagnetic suction value is as follows: Use a voltmeter that can display readings and has a precision of above 0.1 V. Slowly apply power to the magnetic circuit part. When the armature moves, the voltage value at this time can represent the electromagnetic suction of this magnetic circuit part. Compare this voltage value with the threshold value to determine whether the electromagnetic suction meets the product requirements.

[0041] The test method of the present disclosure can be applied to test the electromagnetic suction of the electromagnetic part of any electromagnetic relay. For example, it is used for the JRW-220M relay / 027 specification relay. The initial counterforce (the force that the reed 5 should provide) of this relay is 10 mN, the gap between the armature and the yoke is 0.3 mm, and the operating voltage is 14.2 V. The armature positioning block and the restoring reed are welded on the fixture, and the yoke positioning groove and the gap positioning are provided, as Figure 1 shown, where the reed is made of stainless steel with a thickness of 0.05 mm, and the armature positioning block is made of cupronickel material.

[0042] Install the magnetic circuit part of the relay into the fixture and fix it with a locking head, as Figure 5 shown. According to the counterforce of the finished relay being 10 mN, adjust the angle of the reed so that the counterforce provided by the reed is also 10 mN. Insert a 0.3-mm feeler gauge between the third positioning block and the armature positioning block, adjust the position of the armature positioning block to make the armature and the yoke closely contact, then remove the feeler gauge, make the third positioning block抵住 the bottom end of the armature positioning block, and lock the armature positioning block. At this time, the distance between the armature and the yoke is 0.3 mm. After the reed and the armature positioning block are adjusted, apply power to both ends of the magnetic circuit part. If the operating voltage when the armature can move is less than the specified operating voltage of 14.2 V of the product, it is regarded as qualified.

[0043] This test method simulates the counterforce and gap on the finished relay, so that the magnitude of the electromagnetic suction of the magnetic circuit part can be determined without assembling the magnetic circuit part, and it can be judged whether the electromagnetic suction of this magnetic circuit part is qualified. When the magnetic circuit part of the relay is assembled, its electromagnetic suction is basically fixed and unchanged, and the result of this test method is accurate.

[0044] The present disclosure has been described by the above related embodiments. However, the above embodiments are only examples for implementing the present disclosure. It must be pointed out that the disclosed embodiments do not limit the scope of the present disclosure. On the contrary, changes and modifications made without departing from the spirit and scope of the present disclosure fall within the patent protection scope of the present disclosure.

Claims

1. A method for testing the electromagnetic attraction force of an electromagnetic relay, characterized in that, This method positions the electromagnetic part of the electromagnetic relay under test using a positioning fixture. The fixture positions the gap between the armature and yoke of the electromagnetic part of the relay under test within the required gap range. An excitation is applied to the coil of the electromagnetic part to generate electromagnetic attraction, causing the armature to move. The excitation applied to the coil is gradually increased. The excitation value corresponding to the instantaneous armature movement is compared with a threshold value. If the threshold requirement is met, the electromagnetic attraction of the electromagnetic part of the relay under test meets the requirements. The positioning fixture includes: The first positioning block (1) is configured with a positioning surface (11) and a positioning gap (12). The second positioning block (2) is configured with a yoke positioning groove (21). Third positioning block (3); Armature positioning block (4); During testing, the electromagnetic part of the electromagnetic relay under test is placed on the positioning surface (11), the yoke positioning groove (21) positions the yoke, the bottom ends of the third positioning block (3) and the armature positioning block (4) are respectively assembled in the positioning gap (12), and the bottom end of the armature positioning block (4) can be detachably contacted with the third positioning block (3). Adjusting the position height of the third positioning block (3) in the positioning gap (12) changes the height of the top end of the armature positioning block (4) extending out of the positioning surface (11), thus affecting the armature and adjusting the gap between the armature and the yoke; or adjusting the distance between the third positioning block (3) and the armature positioning block (4) changes the height of the top end of the armature positioning block (4) extending out of the positioning surface (11), thus affecting the armature and adjusting the gap between the armature and the yoke.

2. The electromagnetic relay electromagnetic attraction force testing method according to claim 1, characterized in that, The positioning fixture also includes a spring (5) for providing a holding force, which is obliquely mounted on the positioning surface; during testing, the armature of the electromagnetic part of the electromagnetic relay under test is subjected to a downward force by the spring (5).

3. The electromagnetic relay electromagnetic attraction force testing method according to claim 2, characterized in that, The force provided by the reed (5) is equal to the initial force provided by the reset spring required by the electromagnetic relay under test.

4. The electromagnetic relay electromagnetic attraction force testing method according to claim 1, characterized in that, The second positioning block (2) includes a second positioning block A (22) and a second positioning block B (23) arranged opposite to each other. The yoke positioning groove (21) is formed between the second positioning block A (22) and the second positioning block B (23). The ends of the second positioning block A (22) and the second positioning block B (23) are respectively provided with adjustment holes for the assembly of the adjustment rod (6). The width of the yoke positioning groove (21) is adjusted by the adjustment rod (6).

5. The electromagnetic relay electromagnetic attraction force testing method according to claim 1, characterized in that, The spacing of the yoke positioning groove (21) is the yoke size of the electromagnetic part of the electromagnetic relay under test plus 0.01mm.

6. A positioning fixture, characterized in that: This fixture is used to position the electromagnetic part of the electromagnetic relay under test during the testing of the electromagnetic attraction force of the electromagnetic part, including: The first positioning block (1) is configured with a positioning surface (11) and a positioning gap (12). The second positioning block (2) is configured with a yoke positioning groove (21). Third positioning block (3); Armature positioning block (4); During testing, the electromagnetic part of the electromagnetic relay under test is placed on the positioning surface (11), the yoke positioning groove (21) positions the yoke, the bottom ends of the third positioning block (3) and the armature positioning block (4) are respectively assembled in the positioning gap (12), and the bottom end of the armature positioning block (4) can be detachably contacted with the third positioning block (3). Adjusting the position height of the third positioning block (3) in the positioning gap (12) changes the height of the top of the armature positioning block (4) extending out of the positioning surface (11), thus adjusting the gap between the armature and the yoke; or adjusting the distance between the third positioning block (3) and the armature positioning block (4) changes the height of the top of the armature positioning block (4) extending out of the positioning surface (11), thus adjusting the gap between the armature and the yoke; the gap between the armature and the yoke is positioned within the gap range required by the electromagnetic relay under test.

7. The positioning fixture according to claim 6, characterized in that, It also includes a spring (5) for providing a holding force, which is obliquely mounted on the positioning surface; during testing, the armature of the electromagnetic part of the electromagnetic relay under test is subjected to a downward force by the spring (5).

8. The positioning fixture according to claim 7, characterized in that, The force provided by the reed (5) is equal to the initial force provided by the reset spring required by the electromagnetic relay under test.

9. The positioning fixture according to claim 6, characterized in that, The spacing of the yoke positioning groove (21) is the yoke size of the electromagnetic part of the electromagnetic relay under test plus 0.01mm.

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