An automatic machine head for welding electrical contact assemblies

Abstract

The application provides an automatic welding head of an electrical contact assembly, which comprises a welding head frame, a contact strip driving mechanism arranged at one end of the welding head frame and used for driving an electrical contact strip and pushing a contact obtained by cutting off the front end of the electrical contact strip to a welding position, a contact punching and cutting mechanism arranged at the output end of the contact strip driving mechanism and used for cutting off the front end of the electrical contact strip to obtain the contact, an output end of the contact punching and cutting mechanism is provided with a contact transmission channel, and the contact obtained by punching and cutting is moved to the welding position through the contact transmission channel, and a welding mechanism arranged at the other end of the contact punching and cutting mechanism and used for welding the contact to a supporting strip. The contact transmission channel can guide and position the contact during the pushing and moving process, and the contact will not fall, deviate or overturn. The automatic welding head with the same structure can conveniently realize online welding of a double-sided contact electrical contact assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric contact production, and particularly relates to a head of an automatic electric contact assembly welding machine. BACKGROUND

[0002] The electric contact is a key part in high and low voltage switch electric appliances, and its performance directly affects the quality and service life of the switch electric appliances. The electric contact is usually composed of a contact point directly playing a contact and breaking role and a supporting part playing a supporting and positioning role for the contact point. The contact point and the supporting part are assembled together through mechanical (riveting) and metallurgical (welding) modes to become an electric contact assembly. In a weak current condition, the electric contact with a riveting structure is applied more. However, in a large current, vibration, impact and high temperature condition, the electric contact with a welding structure has more excellent performance, and thus is widely applied.

[0003] In the production process of the electric contact with a welding structure, the contact point and the supporting part are usually separately processed, and then are welded together through a welding machine in an artificial mode or an automatic mode. In the artificial welding process, the feeding and positioning of the contact point and the supporting part are completed through manual work of workers. The automatic welding equipment for this situation usually includes multiple stations, and the contact point and the supporting part are sorted through a vibrating disc, and the contact point and the supporting part are transferred and positioned through a mechanical hand and an auxiliary welding jig. Related equipment patents are CN20529004U - an eight-station full-automatic welding machine, CN202894573U - a full-automatic silver point spot welding machine, CN109659179A - an electric contact welding device, and a linear structure CN106825889A - a full-automatic silver point welding equipment. The welding speed of the automatic welding machine with the multi-station structure is limited by the transmission action speed of the mechanism, and cannot exceed 60 times per minute. Moreover, for the contact point with a front and back requirement, the front and back of the contact point cannot be correctly identified in the sorting process using the vibrating disc, and potential quality risks exist in the welded products.

[0004] Unlike the manufacturing process of electrical contact assembly that the contact and the support are manufactured separately and then sequenced and transferred on the welding machine, the high-speed electrical contact assembly automatic welding machine uses the working mode that the contact and the support are punched and cut on line and the material transfer is carried out by the dragging of the material belt, that is, the so-called punch-weld integrated electrical contact manufacturing process. In this process, the contact is directly cut from the electrical contact material belt before welding, without the need for positive and negative identification, ensuring the correct orientation of the contact. The patents of the punch-weld integrated electrical contact manufacturing equipment found by the search include CN112222835A─a punch-weld integrated equipment, CN107866676A─a punch-weld integrated device and method of electrical contact, CN113441808A─a full-automatic reed welding machine, CN213531579U─a spot welding device and a punch-weld integrated equipment with the spot welding device, and CN201151049Y─an automatic feeding, cutting and welding machine. However, these patent documents only give the basic working steps of the welding process, that is, support material belt feeding→electrical contact material belt feeding→electrical contact material belt cutting→moving the cut single contact to the welding position on the support material belt→contact welding→support material belt feeding to the next welding position. As for the key step of moving the cut single contact to the welding position on the support material belt, the specific operation process of how to realize it is not explicitly stated in these patent documents.

[0005] The patent CN102107321A─a punch-cut-weld integrated mechanism discloses a method of moving the contact by vacuum suction. However, in practice, due to the vibration and impact in the contact punching and cutting process, and the thermal deformation of the upper electrode with vacuum suction holes during the welding process, the vacuum suction method is not very reliable, and the contact may still be displaced, dropped or turned over during the transmission process. SUMMARY

[0006] The technical problem solved by the present application is to provide an electrical contact assembly automatic welding machine head.

[0007] To solve the above technical problems, the present application provides an electrical contact assembly automatic welding machine head, comprising:

[0008] a welding head frame;

[0009] a contact material belt driving mechanism arranged at one end of the welding head frame and used for driving the electrical contact material belt to reciprocate;

[0010] a contact punching and cutting mechanism arranged at the output end of the contact material belt driving mechanism and used for cutting the electrical contact material belt at the front end to obtain a contact, and the output end of the contact punching and cutting mechanism is provided with a contact transmission channel;

[0011] A welding mechanism is arranged at the other end of the contact punching mechanism, and is used for welding the contacts punched by the contact punching mechanism to the support material belt.

[0012] Further, the contact material belt driving mechanism comprises a feeding roller and a pressing roller matched with the feeding roller.

[0013] Further, the feeding roller is provided with a displacement sensor, which is used for measuring the reciprocating transmission length of the electric contact material belt in real time.

[0014] Further, the contact punching mechanism comprises a pad, a reset spring arranged at the bottom of the pad, and a cutter arranged at the top of the pad.

[0015] Further, the welding head frame is provided with a welding head material channel insert block, and a contact transmission material channel is formed between the welding head material channel insert block and the welding head frame.

[0016] Further, the outer end of the welding head material channel insert block is provided with an upper guide block, and the outer end of the welding head frame is provided with a lower limiting block corresponding to the upper guide block, and an auxiliary material channel connected with the contact transmission material channel is formed between the upper guide block and the lower limiting block.

[0017] Further, the welding mechanism is located at the end of the auxiliary material channel away from the contact transmission material channel, and the welding mechanism comprises a lower electrode arranged outside the lower limiting block and an upper electrode arranged outside the upper guide block, and the bottom of the upper electrode is provided with a limiting groove.

[0018] Further, the depth of the limiting groove is less than the thickness of the electric contact material belt.

[0019] Further, the limiting groove is in a U shape, and the limiting groove extends from one end close to the lower limiting block to the middle part of the upper electrode in the length direction.

[0020] Further, the welding head frame is a lifting adjustable welding head frame, which is used for adjusting the height of the contact transmission material channel.

[0021] The electric contact assembly automatic welding head of the present application can smoothly push the contacts in the transmission channel, and the transmission channel plays a guiding and positioning role in the transfer of the contacts, so that the contacts will not fall, deviate or overturn during the transmission process. In addition, the same structure of the automatic welding head can conveniently realize the online welding of double-sided contact electric contact assemblies. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the following embodiment description will be briefly introduced, and the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0023] Figure 1 The schematic diagram of the initial state of the automatic welding machine head of the electrical contact assembly of the present application;

[0024] Figure 2 The schematic diagram of the contact punching process of the automatic welding machine head of the electrical contact assembly of the present application;

[0025] Figure 3 The schematic diagram of the automatic welding machine head of the electrical contact assembly of the present application entering the contact transmission channel after the contact punching is completed;

[0026] Figure 4 The schematic diagram of the automatic welding machine head of the electrical contact assembly of the present application pushing the contact to the welding position;

[0027] Figure 5 The schematic diagram of the process of the automatic welding machine head of the electrical contact assembly of the present application welding the contact and the electrical contact material belt retreating to the initial position;

[0028] Figure 6 The schematic diagram of the upper electrode of the automatic welding machine head of the electrical contact assembly of the present application;

[0029] Figure 7 The schematic diagram of the automatic welding machine head of the electrical contact assembly of the present application in the inverted use.

[0030] The marks in the figure are:

[0031] Contact material belt driving mechanism 100, contact punching mechanism 200, welding mechanism 300.

[0032] Support material belt 1, upper electrode 2, upper guide block 3, cutter 4, welding head material channel insert block 5, compression roller 6, welding head frame 7, electrical contact material belt 8, feeding roller 9, cushion block 10, reset spring 11, lower limit block 12, lower electrode 13, auxiliary material channel 14, contact transmission material channel 15, contact 16, limit groove 17. DETAILED DESCRIPTION

[0033] The above solutions will be further described in combination with specific embodiments. It should be understood that these embodiments are used to illustrate the present application instead of limiting the scope of the present application. The implementation conditions adopted in the embodiments can be further adjusted according to the conditions of specific manufacturers, and the implementation conditions not mentioned are usually the conditions in the conventional experiments.

[0034] Reference Figures 1 to 6As shown in the figure, an automatic welding machine head of an electrical contact assembly comprises a welding head frame 7, a contact strip driving mechanism 100, a contact punching mechanism 200 and a welding mechanism 300. The contact strip driving mechanism 100 is arranged at one end of the welding head frame 7 and used to push the electrical contact strip 8 forward for feeding; the contact punching mechanism 200 is arranged at the output end of the contact strip driving mechanism 100 and used to cut off the electrical contact strip 8 from the front end to obtain a contact 16, and the output end of the contact punching mechanism 200 is provided with a contact transmission channel 15; the welding mechanism 300 is arranged at the other end of the contact punching mechanism 200 and used to weld the contact 16 punched by the contact punching mechanism 200 to the support strip 1.

[0035] The contact strip driving mechanism 100 comprises a feeding roller 9 and a pressure roller 6 matched with the feeding roller 9. The feeding roller 9 is provided with a displacement sensor (not shown) for measuring the reciprocating transmission length of the electrical contact strip 8 in real time. The contact punching mechanism 200 comprises a cushion block 10, a reset spring 11 arranged at the bottom of the cushion block 10 and a cutter 4 arranged at the top of the cushion block 10.

[0036] The welding head frame 7 is provided with a welding head channel insert 5, and the welding head channel insert 5 and the welding head frame 7 form the contact transmission channel 15. The outer end of the welding head channel insert 5 is provided with an upper guide block 3, and the outer end of the welding head frame 4 is provided with a lower limiting block 12 corresponding to the upper guide block 3, and the upper guide block 3 and the lower limiting block 12 form an auxiliary channel 14 connected with the contact transmission channel 15.

[0037] The welding mechanism 300 is located at the end of the auxiliary channel 14 away from the contact transmission channel 15, and the welding mechanism 300 comprises a lower electrode 13 arranged outside the lower limiting block 12 and an upper electrode 2 arranged outside the upper guide block 3, and the bottom of the upper electrode 2 is provided with a limiting groove 17. The depth of the limiting groove 17 is less than the thickness of the electrical contact strip 8. The limiting groove 17 is U-shaped, and the limiting groove 17 extends from one end close to the lower limiting block 12 to the middle part of the upper electrode 2 in the length direction. The welding head frame 7 is a lifting adjustable welding head frame for adjusting the height of the contact transmission channel 15.

[0038] In the first stage, the structure of the automatic welding machine head of the electrical contact assembly in the initial state is as shown in the figure. Figure 1 At this time, the length of the front end of the electrical contact strip 8 located in front of the lower end cutout of the cutter 4 is equal to the length L1 of a single contact 16 to be welded.

[0039] In the second stage, the contact punching process of the automatic welding machine head of the electrical contact assembly is as shown in the figure. Figure 2As shown, at this stage, the cutting knife 4 moves downward to punch out a piece of length Ll of the contact 16 from the front end of the electrical contact strip 8. Below the cutting knife 4, there is a pad 10 of the same size as the cutting knife 4, and below the pad 10, there is a reset spring 11. During the process of the cutting knife 4 moving downward to cut off the contact 16, the pad 10 below the cutting knife will press the cut-off contact 16 tightly and move downward synchronously under the action of the reset spring 11. Through this structure, the flatness of the cutting-off end of the contact 16 at the front end of the electrical contact strip 8 can be improved. After the cutting-off of the contact 16 is completed, the cutting knife 4 retreats to the initial position, and the pad 10 pushes the cut-off contact 16 back to the contact transmission channel 15 under the action of the reset spring 11.

[0040] The third stage, after the completion of the punching of the contact, the contact 16 enters the contact transmission channel 15 as shown in the process of Figure 3 As shown, at this stage, the punching process of the contact 16 has been completed, and the single contact 16 punched out is located in front of the electrical contact strip 8, and both the contact 16 and the electrical contact strip 8 are located in the contact transmission channel 15 inside the welding head frame 7. Then, the upper guide block 3 between the front of the welding head frame 7 and the upper electrode 2 slightly moves downward to press the support strip 1 below it tightly onto the lower limit block 12. This process will limit and fix the vertical position of the support strip 1. At this time, the upper surface of the lower limit block 12 is flush with the upper surface of the lower electrode 13. In order to avoid the shunt effect of the welding current during the welding process, the upper guide block 3 and the lower limit block 12 need to be made of insulating materials. The upper surface of the support strip 1 pressed by the upper guide block 3 needs to be flush with the lower surface of the contact transmission channel 15 inside the welding head frame 7. If the upper surface of the support strip 1 is not aligned with the lower surface of the contact transmission channel 15 inside the welding head frame 7, the height of the welding head frame 7 can be adjusted to align the two. At this stage, the height of the upper electrode 2 will move from Hl downward to H2 position, so that the upper surface of the U-shaped limit groove 17 at the lower welding position of the upper electrode 2 is flush with the upper surface of the auxiliary channel 14. Through the above operation, a closed transmission channel is established between the punched contact 16 and the corresponding welding position on the support strip 1. This transmission channel includes the contact transmission channel 15, the auxiliary channel 14 in front of the contact transmission channel 15, and the auxiliary positioning groove formed between the limit groove 17 at the lower part of the upper electrode 2 and the upper surface of the support strip 1 in front of the auxiliary channel 14. The size of the transmission channel composed of the contact transmission channel 15, the auxiliary channel 14 and the upper electrode auxiliary positioning groove is slightly larger than the cross-sectional size of the electrical contact strip 8, so that the single contact 16 punched out from the front end of the electrical contact strip 8 can be smoothly pushed, positioned and guided during the transfer from the punching position to the welding position, so that the contact 16 will not fall, deviate or turn over during the transmission process.

[0041] In the fourth stage, the process of the automatic welding head of the electrical contact assembly pushing the contacts forward to the welding position is as follows: Figure 4 As shown. The feeding roller 9 rotates forward, driving the electrical contact strip 8, which is clamped between the feeding roller 9 and the pressure roller 6, to move forward. This pushes the contact 16, located at the front end of the electrical contact strip 8, forward within the established contact transmission channel 15, and pushes the contact 16 to the welding position located between the upper electrode 2 and the support strip 1. During this process, the electrical contact strip 8 moves forward a distance of L2.

[0042] In the fifth stage, the contact welding of the automatic welding head of the electrical contact assembly is carried out, and the process of the electrical contact strip 8 returning to its initial position is as follows: Figure 5 As shown. The feeding roller 9 rotates backward, dragging the electrical contact strip 8, which is clamped between the feeding roller 9 and the pressure roller 6, back. The back distance of the electrical contact strip 8 is L3. At this time, the length of the electrical contact strip 8 in front of the cutting edge of the cutter 4 is exactly equal to the length L1 of a single contact 16, i.e., L2 = L3 + L1. Then the upper electrode 2 moves downward, applying welding pressure to the contact 16 and pressing the contact 16 to the welding position corresponding to the support strip 1. At this time, the height from the lower surface of the upper electrode 2 to the support strip 1 is H3. Then, energize the upper electrode 2 and the lower electrode 13 to weld the contact 16 to the welding position corresponding to the support strip 1. When the welding of the contact 16 is completed, the height of the upper electrode 2 pressing the contact 16 will drop slightly. At this time, it is necessary to ensure that the lower surface of the upper electrode 2 does not come into contact with the support strip 1. When the contact 16 is energized for welding, the upper guide block 3 moves slightly upward to open the clamped support strip 1. After contact 16 is welded, the upper electrode 2 moves up to the initial height H1, and then the support strip 1 moves forward to the next welding position. The automatic welding head of the electrical contact assembly then returns to its original position. Figure 1 The initial state shown completes one contact welding operation cycle.

[0043] Figure 6 This is a specific embodiment of the upper electrode 2 used in this invention. A U-shaped groove is formed on the lower end face of the upper electrode 2 to create the limiting groove 17. The depth H4 of the limiting groove 17 is slightly lower than the thickness H0 of the electrical contact strip 8, and the lower surface of the upper electrode 2 will not contact the upper surface of the supporting strip 1 during the welding process. The U-shaped guide and limiting groove 17 on the lower end face of the upper electrode 2 is a basic feature of the upper electrode 2 of this invention. Its specific structure can be integral, combined, or a multi-station turntable structure, and the positioning structure at the front end of this limiting groove 17 can be a stop block, a stop pin, or other limiting methods.

[0044] As a further embodiment of the present application, in the case where the welding position of the contact 16 is close to the edge of the support strip 1, the automatic welding head can not use the auxiliary channel 14 formed by the upper guide block 3 pressing on the support strip 1, but only rely on the contact transmission channel 15 and the limiting groove 17 below the upper electrode 2 to realize the guiding and positioning function of the contact 16 from the cutting position to the welding position. In the transmission process of the contact 16, the support strip 1 needs to be pressed tightly, so that the position of the upper surface of the support strip 1 remains stable and is aligned with the lower surface of the contact transmission channel 15.

[0045] As a further embodiment of the present application, in order to drive the forward and backward movement of the electrical contact strip 8, the driving method used by the contact strip driving mechanism 100 includes a roller feeder composed of the feeding roller 9 and the pressing roller 6, a clamping feeder driven by a servo motor through a screw rod, and a mechanical feeder driven by a servo motor through a cam and lever mechanism. Regardless of which feeder is used, the ultimate function achieved is consistent, that is, the forward distance L2 of the electrical contact strip 8 in each feeding process is slightly greater than the backward distance L3, and the difference between the two is the length L1 of a contact, that is, L2 = L3 + L1.

[0046] As a further preferred embodiment of the present application, the electrical contact assembly automatic welding head can be used upside down, Figure 7 The schematic diagram of the electrical contact assembly automatic welding head used upside down. After the electrical contact assembly automatic welding head is used upside down, the contact 16 can be welded to the lower surface of the support strip 1. When the inverted electrical contact assembly automatic welding head is used to weld the contact 16 to the lower surface of the support strip 1, it is only equivalent to a 180° inversion of the original automatic welding head layout relative to the center plane of the support strip 1, and the structure of the automatic welding head itself does not need to be changed. In the present application, the same structure of the electrical contact assembly automatic welding head can be used to weld the contact 16 above the support strip 1 and below the support strip 1. This switching only needs to adjust the installation method of the welding head without changing the specific structure of the welding head, which shows that the present application has excellent versatility. Therefore, the electrical contact assembly automatic welding head of the present application can conveniently realize the online welding of double-sided contact electrical contact assemblies.

[0047] The above examples are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. An electrical contact assembly automatic soldering machine head, characterized in that, The application relates to a welding head frame, a contact head strip driving mechanism arranged at one end of the welding head frame and used for driving the reciprocating movement of an electric contact head strip, a contact point punching mechanism arranged at the output end of the contact head strip driving mechanism and used for cutting the front end of the electric contact head strip to obtain a contact point, an output end of the contact point punching mechanism being provided with a contact point transmission channel, a welding mechanism arranged at the other end of the contact point punching mechanism and used for welding the contact point cut by the contact point punching mechanism to a supporting strip, the contact head strip driving mechanism comprising a feeding roller and a pressing roller matched with the feeding roller, a displacement sensor being arranged on the feeding roller and used for measuring the reciprocating transmission length of the electric contact head strip in real time, a welding head strip channel insert being arranged in the welding head frame, a contact point transmission channel being formed between the welding head strip channel insert and the welding head frame, an upper guide block being arranged at the outer end of the welding head strip channel insert, a lower limiting block corresponding to the upper guide block being arranged at the outer end of the welding head frame, an auxiliary channel connected with the contact point transmission channel being formed between the upper guide block and the lower limiting block, the welding mechanism being located at the end of the auxiliary channel far away from the contact point transmission channel, the welding mechanism comprising a lower electrode arranged outside the lower limiting block and an upper electrode arranged outside the upper guide block, the bottom of the upper electrode being provided with a limiting groove, the depth of the limiting groove being smaller than the thickness of the electric contact head strip, the contact point punching mechanism comprising a cushion block, a reset spring arranged at the bottom of the cushion block and a cutter arranged at the top of the cushion block. The limiting groove is in a U shape, and the limiting groove extends from one end close to the lower limiting block to the middle part of the upper electrode in the length direction. The welding head frame is a lifting adjustable welding head frame used for adjusting the height of the contact point transmission channel. ​ ​ ​ ​ ​ ​ ​ 2. The electrical contact assembly automatic soldering machine head of claim 1, wherein: ​ 3. The electrical contact assembly automatic soldering machine head of claim 1, wherein: ​

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