CN103920981B

CN103920981B - Resistance welding micro-welding spot welding machine

Info

Publication number: CN103920981B
Application number: CN201410112516.5A
Authority: CN
Inventors: 杨仕桐
Original assignee: GUANGZHOU MICRO WELDING EQUIPMENT CO Ltd
Current assignee: GUANGZHOU MICRO WELDING EQUIPMENT CO Ltd
Priority date: 2013-12-03
Filing date: 2014-03-24
Publication date: 2019-12-24
Anticipated expiration: 2034-03-24
Also published as: CN103920981A; WO2015081594A1; CN103658960A

Abstract

The invention discloses a resistance welding micro-welding spot welding machine, which mainly relates to a machine head, and firstly provides an electromechanical integrated precise electrode force pressurization system arranged on a machine head frame, and realizes that the electrode force is maintained and relatively constant in a preset range in the whole spot welding time period through the synergistic action and mutual restriction of a welding acting force conduction device, a precise electrode force presetting device and a welding force breaking device; then, the structure of a spot welding machine head with an electric control box is provided, and the electric control box is used for feeding electricity to the machine head and presetting the output of a spot welding power supply; the structure of the plastic head frame and the ladder-shaped welding head clamp is also provided to ensure the accuracy of torque transmission; finally, the machine head and the micro-optical device are installed into a whole, so that the invention becomes a brand new resistance welding micro-welding point welding machine with a unique optical, mechanical and electrical integration spot welding machine head.

Description

Resistance welding micro-welding spot welding machine

Technical Field

The invention relates to a micro-welding device, in particular to a resistance welding micro-welding spot welding machine.

Background

The applicant has long been engaged in the development of resistance micro-welding apparatus and is therefore familiar with various implementations of resistance welding apparatus. In general, resistance welding equipment is driven by various welding power supplies, and a head of a spot welding machine generally only provides a structure of a pressurizing mechanism or an electrode holding rod in a general way, so that the structure is relatively simple, and a space for refinement is provided. The applicant has successively held the following patents relating to spot welding equipment:

1. the invention name is as follows: spot welder that can directly weld enameled wire, bulletin number: CN1318449, day of announcement: 24 days 10 months in 2001;

2. the invention name is as follows: take the spot welding machine aircraft nose of pressure display, bulletin number: CN1323675, announcement date: 11/28/2001;

3. the invention name is as follows: a spot welding machine head with a pressure sensor, which is disclosed as follows: CN2728698, announcement day: 9/28/2005;

4. the invention name is as follows: precision resistance spot welder, bulletin number: CN101234452, announcement day: 8/6/2008.

The above-listed patent publications, wherein "spot welder capable of directly welding enameled wire" is awarded by the eleventh Chinese patent, these background arts disclose the technical improvement idea of the applicant all the time, and also sufficiently represent the technical innovation of the resistance welding micro-welding spot welding equipment for over ten years. The resistance welding micro welding needs to accurately control the electrode force, and as for how to accurately control the electrode force, the spot welding machine implemented according to the technical scheme disclosed by the above listed patents is limited to the deficiency of the theoretical basis, or the investment of manpower and material resources for researching the spot welding machine is too little, so that the prior art cannot realize the accurate control of the electrode force in the true sense.

Disclosure of Invention

In order to facilitate a full understanding of the present invention, it is first necessary to understand the differences between the welding force and the electrode force as a basis for the following discussion. In addition, the invention also provides two concepts of 'accurate electrode force presetting' and 'accurate electrode force pressurizing system', and the concepts are also introduced in the preamble.

Differences with respect to welding force and electrode force: the welding force is the acting force for driving relevant mechanical components and electrodes to perform welding operation; the electrode force is a force applied to the weldment by the electrode. Thus, the difference is that the welding force has a longer stroke than the electrode force and the welding force has a greater force than the electrode force.

Accurate electrode force presetting device: the electrode force presetting device is a structure which presets the pressurizing force of a welding electrode on a welding piece in the field of resistance welding and switches on a welding power supply through the electrode force presetting device. The requirement of 'precision' in the 'precision electrode force presetting device' of the invention means that the precision of measuring the electrode force by taking 0.1N as a unit is achieved so as to meet the welding requirement of a tiny workpiece.

Precision electrode force pressurization system: the electrode force pressurization system is a general term for providing electrode force related structures to a welding part during a welding period. The accurate electrode force pressurization system is an electrode force pressurization system which can realize that the output accuracy range of the electrode force provided by a welding piece is +/-0.5N in the whole welding period. The precise electrode force pressurization system must have the following three basic contents: firstly, the electrode force presetting device must be an accurate electrode force presetting device; secondly, the electrode force is maintained in a preset range and kept relatively constant in the whole welding period; thirdly, when welding is completed, the welding piece must be pressed by breaking the excessive welding force.

It should be noted that the precise electrode force presetting device and the precise electrode force pressurizing system are both concepts firstly proposed by the present invention, and the fluctuation of the electrode force in the welding period in the prior art is large, and as described later, the difficulty of realizing the electrode force presetting of ± 0.1N is not very large, but the difficulty of realizing the electrode force of ± 0.5N in the whole welding period is very large. The spot welding machine head of the accurate electrode force pressurization system comprises a welding acting force conduction device, an electrode force presetting device and a welding force breaking device, and the electrode force is maintained and relatively constant in a preset range in the whole welding period through the combined action and mutual restriction of relevant structures of the three parts.

Accordingly, it is a primary object of the present invention to provide a resistance welding micro-welding spot welder with an accurate electrode force pressurization system.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a resistance welding micro-welding spot welding machine, which comprises a spot welding machine head and a spot welding power supply and is characterized in that:

the spot welding machine head is provided with a head frame, the head frame is provided with an accurate electrode force pressurizing system, and the electrode force is maintained and kept relatively constant within a preset range in the whole welding period through the accurate electrode force pressurizing system;

the spot welding machine head is provided with a welding head clamp driven by the electrode force, and the welding head clamp is electrically connected with the spot welding power supply through an output cable.

Specifically, the precise electrode force pressurization system comprises a welding acting force conduction device, a precise electrode force presetting device and a welding force breaking device;

the welding acting force conduction device conducts welding power through the torque of the welding acting force conduction device, and the welding force is converted into electrode force to be conducted to the welding head clamp;

the precise electrode force presetting device provides a setting capable of presetting and quantifying electrode force, and drives a spot welding power supply to provide welding current when the precise electrode force presetting device detects that the electrode force reaches a preset value;

the welding force breaking device blocks the torque transmission of the welding force when the electrode force reaches a preset value.

Specifically, the welding acting force conduction device comprises a welding force conduction structure, an electrode force conduction structure and a welding force buffer structure;

the welding force conduction structure comprises a welding force guide shaft and a welding force conductor; the welding force is guided by the welding force guide shaft to be transmitted through the welding force transmitter;

the electrode force conducting structure comprises an electrode force guide shaft and the welding head clamp; the electrode force is guided by the electrode force guide shaft to carry out torque transmission through the welding head clamp and a welding head arranged on the welding head clamp;

the welding force buffering structure is used for providing a buffering effect for the transmission process of the welding force; the welding force buffering structure comprises at least one compression spring acting between the welding force conducting structure and the electrode force conducting structure.

Specifically, the precise electrode force presetting device comprises a precise electrode force presetting structure and an electrode force circuit;

the precise electrode force presetting structure adopts an electrode force presetting structure of a following structure or an electrode force presetting structure of a pressure sensor, and the electrode force presetting structure is used for setting quantized electrode force;

the electrode force circuit is electrically connected with the resistance welding power supply so that the electrode force circuit controls the on-off of the welding current.

Specifically, the welding force breaking device comprises an electromagnet structure and an electromagnet circuit;

the electromagnet structure comprises an electromagnet and an adsorption iron block; the electromagnet and the adsorption iron block are respectively arranged on a fixed component and a movable component of the machine head; the movable component is provided with a resetting element which enables the movable component to be reset;

the electromagnet circuit is electrically connected with the electromagnet and the electrode force circuit respectively.

Preferably, the spot welding machine head is provided with an electric control box, and the electric control box is provided with a structure for feeding electricity to an electric appliance of the machine head.

Further, the electric control box is provided with a structure for outputting and presetting the electric parameters of the spot welding power supply, and the structure for outputting and presetting the electric parameters comprises a structure preset in a code pulling switch mode or a structure preset by keys in a display screen mode.

Preferably, the machine head frame is a plastic machine head frame. The connection between the electrode force guide shaft of the plastic machine head frame and the welding head clamp is direct connection of metal and metal.

Preferably, the welding head clamp comprises a welding head clamp fixing part, a welding head clamp moving part, a spacing seam between the welding head clamp fixing part and the welding head clamp moving part, and an electrode interface, wherein the welding head clamp fixing part is arranged on the welding head through connection with a sliding shaft provided by the welding head, the electrode interface is opened and closed in the direction of the front vertical face and the rear vertical face of the welding head or in the direction of the left vertical face and the right vertical face of the welding head, and the parallel electrode welding head is arranged on the electrode interface.

Preferably, an electrode interface is arranged between the movable part and the fixed part of the welding head clamp, stepped bosses are respectively arranged at the top ends of the fixed part and the movable part of the welding head clamp block adjacent to the electrode interface, an output cable of the spot welding power supply is arranged on the stepped bosses, and a parallel electrode welding head is arranged on the electrode interface.

Specifically, the electrode interface is arranged at the front side end of the movable part and the fixed part of the welding head clamp, and the parallel electrode welding head is arranged on the electrode interface.

Furthermore, the connection between the welding head clamp and the head sliding shaft realizes the locking of the sliding shaft sleeve through the connecting port formed by the opposite butt joint of the welding head clamp fixing part with each arc-shaped interface and the side edge of another metal piece.

Further, the spot welding machine head and the microscopic optical device are fixedly integrated, the microscopic optical device comprises a microscopic optical bracket and a microscopic optical lens, the microscopic optical lens comprises a stereoscopic microscope head or a single-barrel microscope and a CCD camera, and the microscopic optical lens is arranged on the microscopic optical bracket.

Furthermore, the micro-optical support comprises a cantilever beam fixedly arranged on the frame of the machine head, a stand column, a cross hole frame, a cross column and a frame with angle and focus fine adjustment, wherein the stand column, the cross hole frame, the cross column and the frame are mutually and mechanically connected, and the micro-optical lens is arranged on the frame.

Compared with the resistance welding spot welder in the prior art, the invention mainly provides fundamental technical improvement for the spot welder head, and the invention becomes a brand-new resistance welding micro-welding spot welder with the spot welder head with the unique optical, mechanical and electronic integration through the following five parts of invention contents, and the technical progress of the five parts of invention contents comprises the following steps:

1. the invention firstly provides a mechatronic accurate electrode force pressurization system and an accurate electrode force pressurization system installed on a machine head frame. The precise electrode force pressurization system realizes that the electrode force is maintained and relatively constant in a preset range in the whole spot welding period through the synergistic effect and mutual restriction of the welding acting force conduction device, the precise electrode force presetting device and the welding force breaking device.

2. The invention provides a structure of a spot welding machine head with an electric control box, which presets electric parameters of a spot welding power supply through the electric control box and feeds electricity to the spot welding machine head, simplifies and reduces the electric connection of various electric appliances on the spot welding machine head, and enables the spot welding machine head to be independent of a host machine to become a universal spot welding machine head.

3. The invention provides a machine head frame made of plastic, which realizes the direct metal connection of the connection of a spot welding machine head and a welding head clamp and improves the perpendicularity of welding torque conduction.

4. The invention provides a structure of a stepped welding head clamp, which reduces various losses or errors of welding force in torque transmission.

5. The invention provides a structure for mounting a spot welder head and a micro-optical device into a whole, which not only avoids the micro-optical device from hindering welding operation, but also realizes the unique structure of the spot welder head with optical, mechanical and electrical integration.

The general structure and principle of the present invention will be described below with reference to the block diagram, and then the contents of the present invention will be described one by one according to the above five contents.

Drawings

FIG. 1 is a schematic diagram of the general structure of a resistance welding micro-welding spot welder according to the present invention.

FIG. 2 is a schematic structural diagram of a precise electrode force pressurization system arranged on a head frame of the resistance welding micro-welding spot welding machine.

Fig. 3 is a schematic structural diagram of a spot welding machine head with an electric control box, which is preset by a dial switch, of the spot welding machine head with the electric control box.

Fig. 4 is a schematic structural diagram of a spot welding machine head with an electric control box, which is preset by a display screen, of the spot welding machine head with the electric control box.

FIG. 5 is a schematic diagram of the tip holder of the resistance welding micro-welding spot welder of the present invention, shown side and top views, side by side.

Fig. 6 is a structural view of a spot welder head integrally mounted with a micro-optical device of the present invention, showing front and side views thereof in a side-by-side manner.

Detailed Description

It should be understood that the concept of "resistance welding micro-welding" of the present invention is proposed for miniature workpieces that cannot be resistance welded under direct vision, and the resistance welding micro-welding requires not only precise electrode force and welding energy, but also welding operation under a micro-optical device. The present invention focuses, by way of example only, on a spot welder head, a weld head holder, and a micro-optical device.

FIG. 1 is a block diagram schematically illustrating the general structure of a resistance welding micro-welding spot welder according to the present invention.

In fig. 1, a large box 101 represents a head frame, a small box 102 represents welding power (welding force) provided by a spot welder as an external power source, 103 represents a welding force conducting structure, 104 represents a welding force buffering structure, 105 represents an electrode force conducting structure, 106 represents a precise electrode force presetting device, 107 represents a welding force breaking device, 108 represents a welding head clamp and an electrode, 109 represents a welding piece, 110 represents a host machine provided with a spot welding power supply and a spot welding power supply regulating device, 111 represents an electronic control box, and 112 represents a micro-optical device, wherein solid line arrows represent an acting force (moment) conducting relation, and dotted line arrows represent a current or electric signal conducting relation; the single arrow is single acting and the double arrow is double acting. It will be appreciated that fig. 1 describes the spot welder of the present invention primarily in terms of two main lines of force action versus electrical action, i.e., mechatronics.

It should be noted that the precise electrode force pressurization system includes, in addition to the welding acting force conduction device composed of the welding force conduction structure 103, the welding force buffer structure 104 and the electrode force conduction structure 105 in fig. 1, a precise electrode force presetting device 106 and a welding force breaking device 107, and the above structures are mutually restricted by the cooperation of mechanical and electrical integration to achieve the basic effect required by the precise electrode force pressurization system; the electric control box is mainly used for feeding electricity to an electric appliance on the machine head and presetting electric parameters output by a spot welding power supply; the precise electrode force pressurization system and the electric control box are arranged around the machine head frame to form the head part of the spot welding machine.

The following five inventive contents are introduced one by one.

First, the contents of mounting a mechatronic precision electrode force pressurization system on a handpiece frame will be described.

The welding force transmission device and the precise electrode force presetting device in the precise electrode force pressurization system will be described with reference to fig. 2.

In fig. 2, the head frame has four front, rear, left and right vertical faces, the front vertical face of the head frame is 201, and the rear vertical face and the left and right vertical faces of the head frame are also defined after the front vertical face of the head frame is defined. An upright column 202 is fixed on the vertical surface near the back of the machine head frame, and the lower section of the upright column is fixedly arranged on the workbench. A small shaft 203, a middle shaft 204 and a sliding shaft 205 which are arranged in parallel with the upright column 202 are arranged on the nose frame; there are also a center clamp 206 and a slide clamp 207 mounted in a perpendicular orientation to the column 202. One end of the middle shaft clamp 206 is fixedly connected with the middle shaft 204, the other end of the middle shaft clamp 206 is sleeved on a welding power transmission pull rod (or a pull cable) 222, one end of a return spring 221 is connected with the middle shaft clamp 206, and the other end of the return spring is connected with a supporting piece sleeved on the pull rod; one end of a sliding shaft clamp 207 is fixedly connected with a sliding shaft 205, the upper section and the lower section of the middle shaft 204 are respectively provided with a compression spring 208 and a compression spring 209, the sliding shaft clamp 207 is arranged by penetrating through the middle shaft 204, and the upper end face and the lower end face of the sliding shaft clamp 207 are respectively abutted against or connected with the compression springs 208 and 209 at the corresponding position where the sliding shaft clamp 207 is penetrated through by the middle shaft 204; the small shaft 203 penetrates through the middle shaft clamp 206 and the sliding shaft clamp 207 in a slidable connection mode; in addition, the small shaft 203 is also divided into an upper section and a lower section which are provided with compression springs 210 and 211, and the upper end surface and the lower end surface of the sliding shaft clamp 207 at the corresponding position where the small shaft 203 penetrates through are respectively abutted against or connected with the compression springs 210 and 211; the lower end of the slide shaft 205 is used to fixedly connect with the welding head clamp 212, the parallel electrode welding head 223 is installed on the welding head clamp 212, and the spot welding power source 213 is connected with the parallel electrode welding head 223 through the welding head clamp 212 by the output cable 214.

The welding force transmission structure provided by the invention comprises the small shaft 203, the middle shaft 204, the middle shaft clamp 206 and the sliding shaft clamp 207 which realize a given installation structure.

The electrode force conducting structure proposed by the present invention includes the slide shaft 205 and the tip holder 212 which realize a given mounting structure.

The welding force buffering structure of the present invention includes a first set of compression springs 208, 209 and a second set of compression springs 210, 211 mounted on the middle shaft 204 and the small shaft 203, respectively.

In terms of the functions realized by the above components, the small shaft 203 and the middle shaft 204 are guiding shafts for welding force, the middle shaft clamp 206 and the sliding shaft clamp 207 are conductors for welding force, the small shaft 203 and the sliding shaft 205 are guiding shafts for electrode force, and the welding head clamp 212 is a conductor for electrode force. The welding force transmission structure, the electrode force transmission structure and the welding force buffer structure form the welding acting force transmission device.

It is necessary to further explain the welding force buffering structure. As can be understood from the structure of the present embodiment, the essence of the welding force buffering structure is a compression spring installed between the welding force transmitting structure and the electrode force transmitting structure, and the function of the compression spring includes transmitting the welding force to the electrode force transmitting structure softly and maintaining the welding force under the action of the compression spring when the welding force is broken, that is, by providing a structure for buffering the transmission of torque in the torque transmission path, the transmission of force is made softer, i.e., the welding force buffering structure of the present invention is formed. Therefore, based on the same principle of the present embodiment, it should be understood by those skilled in the art that the specific implementation manner of the welding force buffering structure can be varied, for example, the present embodiment can be modified to only maintain one set of spring combination of the welding force buffering structure, or only one compression spring is disposed between the welding force transmitting structure and the electrode force transmitting structure (e.g., the compression spring is disposed between the upper middle shaft clamp 206 and the middle sliding shaft clamp 207 of the small shaft 203, and the other three compression springs are omitted), and all of them belong to the welding force buffering structure proposed by the present invention, and fall into the protection scope of the present invention.

In the configuration of fig. 2, the compression springs 208, 209, when embedded in the central axis, can act as a buffer as previously described and can be considered part of the weld force buffer configuration, but, from another functional perspective, by adjusting the compression position of the springs 208, 209, they further act as precise electrode force presets and follow the configuration. The electrode force circuit 216 is installed at the front end of the handpiece frame 201, and the precise electrode force presetting structure and the electrode force circuit constitute the precise electrode force presetting device of the invention. In the precise electrode force presetting structure, the elastic coefficient of the upper and lower compression springs 208 and 209 is set when the compressor is shipped, and the reaction of the releasing force to the external force is also set.

As described above, the precise electrode force presetting device includes a precise electrode force presetting structure and an electrode force circuit, the precise electrode force presetting structure can be realized by a pressure sensor structure in addition to the following structure shown in fig. 2, and the electrode force circuit is electrically connected to a host machine on which the spot welding power supply and the spot welding power supply regulating device are installed.

It should be noted that the compression springs 208, 209 described above serve a very smart function in the above-described embodiment, both as a weld force buffer and a follow-up maintenance feature, and as a precise electrode force presetting feature. And as analyzed by the various examples of variations previously disclosed with respect to the weld force buffer configuration and the precise electrode force preset configuration, the implementation of the compression springs 208, 209 that are not necessary for both configurations may be substituted in some embodiments, however, it is clearly preferred to implement both configurations simultaneously with the compression springs 208, 209. The person skilled in the art should have a clear knowledge of this.

The structure of the weld force snapping apparatus in a precision electrode force pressurization system will be described with reference to fig. 2.

The welding force breaking device comprises an electromagnet structure and an electromagnet circuit used for driving the electromagnet structure to work, the electromagnet structure comprises an electromagnet and an adsorption iron block, the electromagnet and the adsorption iron block are respectively installed on a fixed component and a movable component of a spot welding machine head, and the electromagnet circuit is electrically connected with an electrode force circuit of the accurate electrode force presetting device.

When the electromagnet circuit is switched on, the electromagnet in the electromagnet driving structure adsorbs the adsorption iron block. In order to realize the operation cycle, the electromagnet structure must have a reset member, which is a member that returns the attracted iron piece attracted by the electromagnet to the original position when the electromagnet circuit is turned off. There are many resetting members, and a known structure, such as an extension spring, a permanent magnet with a polarity opposite to that of the electromagnet, etc., can be adopted to assist the resetting of the adsorbed movable member, which will not be described in detail since those skilled in the art will know.

Fig. 2 is a schematic structural view of an electromagnet and an adsorption iron block respectively arranged on a fixed component and a movable component of a spot welding machine head. As shown in fig. 2, an electromagnet 217 is mounted on the upper frame of the handpiece frame 201, an adsorption iron block 218 is mounted on the adsorption surface adjacent to the electromagnet, a reset member 219 is mounted on the upper ends of the center shaft 204 and the slide shaft 205, and the adsorption iron block 218 and the reset member 219 are connected by a shaft pin 220.

Because the middle shaft 204 belongs to the movable component, once the iron block on the middle shaft 204 is adsorbed by the electromagnet in the movement process, the middle shaft 204 can play a role in blocking in the welding force transmission process, thereby playing a role in breaking. Once the electromagnet circuit is disconnected and the electromagnet is demagnetized, the reset member 219 on the middle shaft 204 is reset to force the middle shaft 204 to remove the external force and reset, thereby recovering the normal stress environment of the middle shaft 204.

As mentioned above, the present invention divides the structure of the spot welding machine head into the movable component and the fixed component, and is not limited to the understanding of the two components, i.e. the upper frame and the centering shaft 204 of the machine head frame, and in fact, those skilled in the art can understand from the description of the present invention that the movable component referred to in the present invention includes movable components such as a middle shaft clamp, a middle shaft, a small shaft, a sliding shaft clamp, and a sliding shaft; the fixed member includes a head frame or the like fixed relative to the movable member. Any fixed member or movable member can be designed by those skilled in the art according to conventional design principles to cooperate with the electromagnet and attracting magnet and the reset element, without limitation of the existing structure.

It is necessary to summarize the following three structural features of the precise electrode force pressurization system of the present invention:

(1) the mechanical and electrical integration has the structural characteristics that:

according to the overall design of the precise electrode force pressurization system, the precise electrode force pressurization system comprises a welding force conduction structure, a welding force buffer structure, an electrode force conduction structure, an electromagnet circuit, a precise electrode force presetting structure and an electrode force circuit, wherein the electrode force circuit plays an important control role in the whole precise electrode force pressurization system. When a workpiece is to be welded, firstly, an electrode force to be preset is input on a precise electrode force presetting device in a quantitative mode through an electrode force circuit, then, during operation, a welding power source provides welding force for a welding force conductor, when the electrode force circuit detects that the welding force reaches a preset value, the electrode force circuit sends an instruction to the welding power source on one hand to turn on a spot welding power source, and sends an instruction to an electromagnet circuit on the other hand to enable an electromagnet to be turned on to adsorb the adsorption iron block, and the electromagnet structure brakes the welding force conduction structure to prevent torque conduction to prevent overlarge welding force from acting on the electrode.

(2) The welding force breaking device has the structural characteristics that:

the welding member for electric resistance welding micro welding is generally less than 0.10mm, on one hand, the invention adopts a welding force braking device which is not influenced by the height difference of the welding member, the braking in the prior art adopts a stroke limiting structure, for example, a servo motor with the best braking precision in the prior art, the stroke limiting precision of the servo motor is less than 0.01mm, but the requirement of electric resistance welding micro welding cannot be met, because the condition that the height difference of the welded workpiece reaches 0.03mm is quite common, the servo motor has no way for the error of the workpiece by the stroke limiting, the invention simultaneously triggers the working signals of the electromagnet by the trigger signal of a spot welding power supply, and the braking of the invention is not influenced by the height difference of the welding member at all. When the spot welding operation is completed, the electrode force circuit cuts off the spot welding current provided by the spot welding power supply, and simultaneously the welding force breaking device is instructed to restore to the original state, namely, a spot welding process is completed.

(3) The electrode force buffer structure has the structural characteristics that:

the principle of action of the welding force buffering structure seems simple, but the welding force buffering structure is also an important component of the precise electrode force pressurization system. The whole spot welding time interval of the resistance welding micro welding requires that the electrode force is kept relatively constant in a preset range, the precision requirement of +/-0.1N for a precise electrode force presetting device is not too difficult, however, the spot welding process of the resistance welding is in a completely closed and unobservable state, the spot welding process comprises the coupling action of electricity, heat, force and multivariable, the coupling action is highly nonlinear, and a welding piece is in a very short nucleation process of softening and flattening after being heated and expanded, so the precise electrode force pressurizing system is required to keep the electrode force in the precision range of +/-0.5N in the whole welding time interval, and the difficulty is very high. It is possible to envisage: without the follow-up maintenance of the weld force buffer structure, it would appear that the electrode force increases as the weldment expands, decreases as the weldment collapses, and disappears as the weld force is pulled. The electromechanical integrated precise electrode force pressurization system realizes that the electrode force is maintained in a preset range and kept relatively constant in the whole spot welding period through the precise electrode force presetting device combined with the synergistic action and mutual restriction of the welding force braking device and the welding force buffering structure, and well solves the technical problem of electric resistance welding micro-welding.

Secondly, the structure of the spot welding machine head with the electric control box is introduced, because the electromechanical integrated precise electrode force pressurizing system arranged on the machine head frame relates to more electric appliances, such as detection and display of preset electrode force, electromagnet, treatment of electromagnetic remanence, regulation and control of adsorption time of the electromagnetic remanence and the like, the electric control box is provided and is integrally arranged with the machine head, the electric control box not only feeds electricity to the electric appliances of the spot welding machine head, simplifies and reduces the electric connection of various electric appliances on the spot welding machine head, so that the spot welding machine head can be independent of a host machine to become a universal spot welding machine head, but also can be arranged on the electric control box, and the welding operation becomes more convenient.

It is necessary to further explain the technical features of the electrical control box.

The main machine of the resistance welding spot welder is provided with a spot welding power supply and a regulating and controlling device for outputting the welding power supply, the output of the welding power supply is required to be very accurate due to the fact that micro welding of resistance welding requires that the output voltage is required to be 0.01V and the output time is required to be 0.1ms, in order to achieve the purpose, the output regulating and controlling device regulates and controls the welding power supply through a plurality of independent circuits and dozens of electric signal lines, therefore, the regulating and controlling device and preset function keys in the prior art need to be arranged on the main machine together with the spot welding power supply, electric appliances on the machine head feed electricity through the main machine, and the machine head of the spot welder can be electrically connected with a matched main machine. The invention redesigns the welding power supply regulating and controlling device, realizes that the preset function key output by the welding power supply and the feeding structure of the host computer to the electric appliance are both arranged on the electric control box, and only the electric signal for triggering the welding power supply is provided for the host computer, so that the spot welding machine head with the electric control box can work, and the spot welding machine head with the electric control box becomes an independent and universal machine head. The invention makes the production, installation and maintenance of the spot welding machine head simple and convenient, and further has further profound technical progress in the aspects of establishment of industry standards, quality management and the like.

The most common structure for presetting power supply parameters by a spot welding power supply is presetting by a code switch mode and presetting by a key in a display screen mode, and the structure of a spot welding machine head with an electric control box is described in the following by combining an attached figure 3 and an attached figure 4.

FIG. 3 is a diagram showing the presetting of output voltage and output pulse width by means of a toggle switch for the output of a spot welding power supply;

in fig. 3, the head of the spot welding machine is 301, a welding force display 302 is arranged on the front outer side of the head, an electromagnet structure 303 of a welding force breaking device is arranged above the head, an electric control box 304 is fixedly arranged on the outer side surface of the head of the spot welding machine, the electric control box and the head are an integrated installation structure, the electric control box provides a power supply circuit for feeding or/and regulating and controlling electricity consumption for various electric appliances of the head, an electric socket or/and electricity consumption regulating and controlling knob 305 for various electric appliances of the head is arranged on the upper side surface of the electric control box, the electric appliances including the welding force display 302, the electromagnet structure 303, a CCD307, a ring lamp 308, a liquid crystal display screen 309 of a micro-optical device and the like are electrically connected with the electric control box, a code pulling switch 306 with two function keys for presetting output pulse amplitude and pulse width of a spot welding power supply is arranged in front of the electric control box, and a cable and an external market are arranged on the rear side surface of the An electrical power line.

Fig. 4 shows presetting of output current amount and current time by pressing a button in a display screen manner for output of a spot welding power source.

In fig. 4, the head of the spot welding machine is 401, there is a welding force display 402 on the front outer side of the head, there is an electromagnet structure 403 of the welding force breaking device above the head, there is an electric control box 404 on the outer side of the head of the spot welding machine, the electric control box and the head are integrated, the electric control box provides a power circuit for feeding or/and regulating the power consumption of various electric appliances of the head, there is an electric socket or/and power consumption regulating knob 405 on the upper side of the electric control box for various electric appliances of the head, the electric appliances including the welding force display 402, the electromagnet structure 403, a CCD407, a ring lamp 408, a liquid crystal display 409 of a micro-optical device, etc. are all electrically connected with the electric control box, there are a display 406 for presetting the electrical parameters of the spot welding power supply and a function key 410 preset according to the display in front of the electric control box, there are cables electrically connected with the host machine equipped with the spot welding power supply and the spot welding power supply regulating device and a .

Thirdly, the invention provides a structure of a plastic machine head frame. The following describes the inventive content of the plastic head frame.

The machine head frame in the prior art adopts a metal machine head frame, in order to ensure the accuracy of spot welding, the resistance welding spot welding has strict requirements on the verticality and radial swing of a welding head, otherwise, welding instability or welding part slippage can easily occur during welding, the invention is more difficult in this respect because firstly, the invention is often used for spot welding wires such as enameled wires and cylindrical wires are easier to slide, secondly, the invention mainly adopts one-side welding with parallel gaps, two electrodes are both arranged on the same welding head clamp, because the welding head clamp and the sliding shaft are both made of metal, therefore, the welding head clamp and the sliding shaft of the frame of the machine head can be connected only by adding an insulating material interval, so that the verticality of the welding head is easily influenced, particularly if a user adjusts the welding head by himself, the perpendicularity of the welding head cannot be controlled, and how to ensure the perpendicularity of the welding head and reduce radial swing is important technical content for further improving the welding quality.

The invention gets rid of the inertia thinking, and uses plastic to manufacture the frame of the machine head to replace the original metal frame of the machine head. The plastic machine head frame is produced by the die, so that the processing precision is greatly improved, the radial swing of the sliding shaft can be reduced, more importantly, the plastic machine head frame is adopted, the sliding shaft and the welding head clamp can be directly connected by metal without an insulating material interval, and the practical significance for improving and ensuring the perpendicularity of the welding head clamp is achieved.

It should be noted that the present invention proposes that the sliding shaft and the welding head clamp are directly connected between metal and metal, including welding, riveting, tight fitting, or screwing.

Fourth, the present invention provides a step-like tip holder structure. The structure of the step-like horn holder will be described below.

Resistance welding spot welding must ensure that pressurization and pressure relief are rapid and flexible. When one welding operation is finished, the structures of the reset spring of the machine head and the like are beneficial to pressure relief, so that the welding stroke returns to the original position, and the next welding operation is convenient to enter. In order to ensure that the spot welding machine can perform the reciprocating spot welding operation, the pressurizing and pressure-relieving operations are rapid and flexible, and besides the structure of the head of the spot welding machine, the pressurizing and pressure-relieving operations are also very important for whether the output cable on the head clamp influences the pressurizing and pressure-relieving operations. Because resistance welding micro-welding adopts the mode of low voltage heavy current, output cable is all bigger, generally all is more than phi 10mm, but for the convenience of operation, the welding head presss from both sides and requires very small and exquisite again, and the width of welding head clamp front end is only about 30 mm. In addition, in order to ensure the accuracy of output energy, two feedback lines are required to be arranged on a welding head clamp close to two electrodes for acquiring feedback signals, two large output cables are required to be arranged on a small welding head clamp, and two feedback lines are required to be arranged.

The precision electrode force pressurization system can only ensure that the electrode force remains constant when welding is performed a second time. In practical application, the electrode force of each welding is kept constant when continuous welding is carried out. It is necessary to further examine the two output cables mounted on the tip holder, and if the output cables mounted on the tip holder affect the pressurization and depressurization of the electrode force, it is not advantageous to provide an accurate electrode force, which is not considered by the prior art tip holder.

The invention relates to a welding head clamp, which comprises a welding head clamp fixing part and a movable part, wherein the welding head clamp fixing part and the movable part are formed by two metal clamping blocks, and the welding head clamp fixing part and the movable part are connected with a machine head sliding shaft through the fixing part and are arranged on a hot press head.

The front vertical surface, the rear vertical surface, the left vertical surface and the right vertical surface of a machine head and a machine head frame of the spot welding machine are required to be described, when a welding head clamp fixing part and a machine head sliding shaft are connected and installed on the machine head, a spacing seam and an electrode interface which are formed between the welding head clamp fixing part and a movable part are generally vertical to the front vertical surface of the machine head, the electrode interface can perform left-right opening and closing movement in the direction of the left vertical surface and the right vertical surface of the machine head, the welding head clamp is called as a longitudinal clamping type welding head clamp, and the longitudinal clamping type welding head clamp with the structure is adopted; the invention provides a spacing seam formed between a fixed part and a movable part of a welding head clamp and an electrode interface which are generally parallel to the front vertical surface of a machine head, wherein the electrode interface can perform front and back opening and closing movement in the direction of the front and back vertical surfaces of the machine head.

The welding head clamp comprises a welding head clamp fixing part, a welding head clamp moving part, a spacing seam between the welding head clamp moving part and the welding head clamp moving part, and an electrode interface, wherein the welding head clamp fixing part is connected with a machine head sliding shaft and installed on the machine head, the electrode interface can perform front-back opening and closing movement in the direction of the front vertical surface and the back vertical surface of the machine head of the spot welding machine, and the parallel electrode welding head is installed on the electrode interface.

In the invention, the electrode interface of the welding head clamp is arranged at the front side end of the welding head clamp closer to an operator, so that the exposure of a weldment and the welding operation are more facilitated.

In order to further enhance the verticality of the transverse welding head clamp installed on the machine head sliding shaft, in the invention, for the connection of the transverse clamping welding head clamp and the machine head sliding shaft, the welding head clamp can be further fixedly designed to be provided with an arc interface, and the sliding shaft is sleeved and locked by virtue of another metal piece with the arc interface and the welding head clamp fixing part.

The invention also provides a structure of the stepped welding head clamp, wherein stepped bulges are respectively arranged at the top ends of the welding head clamp movable part and the welding head clamp fixed part which are adjacent to the electrode interface, and two thick output cables cross two sides of the sliding shaft and straddle over the welding head clamp to be installed, so that rapid and flexible spot welding pressurization and pressure relief are realized, and the guarantee is provided for keeping the electrode force unchanged during each welding; in addition, the invention also further sleeves two feedback lines in the insulating outer sleeve of the output cable, the leading-out terminal of the feedback lines is connected with the leading-out terminal of the output cable and shares the same terminal, not only two feedback lines are reduced in appearance, but also two terminal ends and wiring screws are reduced on the welding head clamp, and the structure is also beneficial to the rapidness and flexibility of pressurization and pressure relief.

The solder head clip of the present invention is further described below with reference to fig. 5.

As shown in fig. 5, the solder holder 500 is formed by processing two copper materials with good electrical conductivity into a solder holder fixing portion 501 and a solder holder moving portion 502, respectively, a connecting port 504 connected with a head sliding shaft 503 is provided at a corner of the solder holder, and the solder holder is fastened on the head sliding shaft 503 through the connecting port 504; the movable part 502 of the weld holder is at the front position facing the operator, the movable part 502 of the weld holder can be opened and closed relative to the fixed part 501 of the weld holder by an adjustable screw 505 and a plastic movable positioning pin 506, the movable part 502 and the fixed part 501 are locked at ordinary times, and the operation is carried out by adjusting the adjustable screw 505 when the parallel electrode welding head needs to be replaced.

In order to fix the welding head clamp and the head sliding shaft more reliably and ensure the vertical degree of the welding head clamp and the head sliding shaft, the connecting port 504 is realized by adopting two metal piece locking structures 507 with semicircular interfaces respectively, namely the fixing part is used as a metal piece, a metal piece is additionally arranged, the two metal pieces are butted at the side edges, the semicircular interfaces are arranged at the opposite side edges, and the two metal pieces can be locked by screws, so that the connecting port 504 is formed and the locking sliding shaft is sleeved by the connecting port 504.

To facilitate exposing the weldment and performing the welding operation, an electrode interface 508 is provided at the front side of the weld head holder, closer to the operator, and a conventional electrode interface is provided at the center of the front side of the weld head holder. The electrode interface 508 is realized by the joint fit of the weld holder fixing part 501 and the weld holder moving part 502, specifically, opposite arc interfaces are respectively arranged on the side edges installed oppositely, and a through hole is formed by the joint fit of the two interfaces, thereby forming the electrode interface 508.

In order to ensure that the electrode force is uniform and consistent in each welding operation, the welding head clamp adopts a step-shaped welding head clamp, and the structure of the welding head clamp is that step-shaped protruding parts 509 and 510 are respectively arranged at the top ends of a welding head fixing part 501 and a welding head clamp moving part 502 which are adjacent to an electrode interface 508, two output cables 511 and 512 are installed on the step-shaped protruding parts through cable ends to realize the electrical connection of a resistance welding power supply and the step-shaped welding head clamp, feedback wires 513 and 514 are sleeved in an insulating sleeve of the output cables and welded on the cable ends, and a parallel electrode welding head 515 is installed on the electrode interface 508, so that the two output cables and the feedback wires cross a sliding shaft and are installed at the top end of the step-shaped welding head clamp in a straddling manner.

It should be noted that the requirement of micro welding on the verticality and reliability of the welding head clamp installation is very high, the existing welding head clamp and the machine head sliding shaft are connected and fixed by 1-3 locking screws, the connection is only a 'point' fixing mode, and the verticality of the welding head clamp after connection is difficult to guarantee. It should be noted that, each of the circular arc interfaces includes two semicircular arc interfaces or a small circular arc interface and a large circular arc interface, the connection ports may be disposed on the left and right sides of the welding head holder fixing portion, or on the rear side of the welding head holder fixing portion, and it is only necessary to pay attention to the separation from the parallel electrode welding head, and these structures similar to the technical means disclosed in the present invention all belong to the equivalent structure of the present claims, and fall into the protection scope of the present invention.

It should be noted that, as an alternative technical means, the electrode interface 307 may be in a longitudinal-clamping type configuration as shown in fig. 3, or may be in a transverse-clamping type configuration, and the longitudinal-clamping type configuration or the transverse-clamping type configuration of the electrode interface falls within the protection scope of the present invention as set forth in the claims.

The effect of the output cable on the electrode force during spot welding was analyzed below for the different configurations of the tip holder of the spot welder according to the invention and patent No. (ZL 011148314).

The output cables are arranged on two sides of the welding head clamp in a patent (ZL 011148314), and the connection of the output cables and the welding head clamp respectively has three conditions of downward deviation, upward deviation or no deviation. Because the output cable is certainly provided with an elastic force when being bent, if the connection of the output cable and the welding head clamp deviates downwards, the pressurizing of spot welding is influenced; and the connection of the output cable is deviated upwards, which affects the voltage relief. Even if the output cable is installed without deviation, the dead weight of the thick output cable causes the rear section cable to bend and draw the welding head due to the output cable arranged behind the sliding shaft, and further influences the pressurization and pressure relief and the accuracy of the electrode force.

The step-shaped welding head clamp is characterized in that the output cable crosses two sides of the sliding shaft and is arranged above the welding head clamp, so that the position of the output cable connected to the welding head clamp is in an approximately horizontal position (relative to the height of a lead of a resistance welding power supply) without deviation, the influence of the elastic force of bending deformation of the cable on the electrode force is reduced, the sliding shaft is a main shaft of a welding acting force conduction structure, the output cable crosses two sides of the sliding shaft and is arranged above the welding head clamp, the cable and the welding head clamp can be ensured to be kept in the same horizontal direction, and the pulling force generated by bending of the cable is greatly reduced. When welding operation is carried out, the sliding shaft drives the cable in the horizontal direction to do reciprocating movement with a short stroke together with the welding head clamp, only the dead weight of the cable is left due to the influence of the output cable on the electrode force, the dead weight of the cable is the same as that of the welding head clamp and can be overcome by the reset spring of the machine head, and therefore the influence on the electrode force is small.

It should be noted that the step-like pad holder in the figures is only one of the structures that implement the mounting of the output cable straddling over the pad holder across both sides of the slide shaft. The ladder bellying of utensil cable interface both can form for the whole processing of inseparable same metal with the bonding tool holder, the ladder bellying also can be two metal blocks of separation with the bonding tool holder, process two little metal block liners in addition in the below of cable end, again with fastening screw output cable connection in the preceding top of bonding tool holder, these structures belong to the equivalent structure that ladder appearance bonding tool pressed from both sides, belong to the equivalent structure of striding the output cable and riding in bonding tool holder top installation beyond the sliding shaft both sides.

Fifthly, the structure that the spot welding machine head and the micro-optical device are integrally installed is described.

The resistance welding micro-welding spot welder is also provided with a micro-optical device. The micro-optical device comprises an optical head and a bracket, wherein the bracket is required by micro-welding operation to adjust the front and back directions, the left and right directions and the angle of the optical head during focusing and to adjust the rough adjustment and the fine adjustment of the focal length during adjusting, so the bracket of the traditional micro-optical device is arranged beside the head of a spot welding machine in an independent structure, and thus, the upright post of the bracket inevitably hinders the welding operation. The invention provides a structure for mounting a spot welder head and a micro-optical device into an integral structure, wherein a cantilever beam is mounted at the top end of a head frame and connected with a bracket of the micro-optical device, and the problems that the original stand column hinders welding operation and the micro-optical device is focused and focused are solved.

Referring to fig. 6, a cantilever beam 602 is mounted at a suitable position on the top end of a handpiece frame 601, the left outer side of the cantilever beam is provided with a column connecting hole, a column 603 of a micro-optical device support is mounted on the outer side of the cantilever beam 602 through the column connecting hole, the column 603 and a cross column 604 are respectively mounted on a cross-hole frame 605, a frame 606 with fine adjustment of angle and focal length is connected with the cross column 604, and an optical handpiece 607 is mounted on the frame 606 with fine adjustment of angle and focal length.

It should be noted that the optical head proposed in this embodiment may be a stereoscopic microscope head, or may be a monocular microscope with a CCD camera or other microscope heads, such as a three-channel microscope head or a CCD camera with image recognition, and it should be noted that electrical appliances related to the microscope optical device, such as an illumination lamp and a liquid crystal display, may also be provided by a low-voltage dc power supply of the electronic control box.

During operation, the height of the upright post can be adjusted on the cantilever beam through the upright post connecting hole, so that the requirement of the optical head on coarse focusing is met; the cross column can be adjusted on the cross hole frame, so that the requirement of the optical machine head on front and back direction adjustment is met; because the upright post can rotate on the upright post connecting hole, the requirement of the optical head on the left-right direction adjustment is realized, the bracket of the micro-optical device is arranged at the top end of the head frame, so that the spot welding machine head and the micro-optical device form an integrated structure, and the technical problem that the upright post obstructs welding operation is solved.

Summarizing the five contents of the invention, the invention firstly provides a mechatronic precise electrode force pressurization system and introduces a great deal of description on installing the precise electrode force pressurization system on a machine head frame; then, a spot welding machine head with an electric control box is provided, the electric control box is used for feeding power or/and regulating and controlling the power consumption of the spot welding machine head, the output of a spot welding power supply is preset and is also arranged on the electric control box, and the electromechanical integration of the spot welding machine head is realized; in order to ensure the accuracy of the welding force in the whole moment conduction, the structure of a plastic machine head frame and a step-shaped welding head clamp is also provided; finally, the invention also installs the spot welder head and the micro-optical device into a whole, which makes the invention become a resistance welding micro-welding spot welder with a spot welder head with the unique optical, mechanical and electrical integration.

Claims

1. The utility model provides a resistance welds micro-welding spot welding machine, includes spot welder aircraft nose and spot welding power, its characterized in that:

the spot welding machine head is provided with a machine head frame, the machine head frame is provided with an accurate electrode force pressurizing system, and the accurate electrode force pressurizing system comprises a welding acting force conduction device, an accurate electrode force presetting device and a welding force breaking device;

the welding acting force conduction device comprises a welding force conduction structure, an electrode force conduction structure and a welding force buffer structure; the welding force conduction structure comprises a welding force guide shaft and a welding force conductor; the electrode force conducting structure comprises an electrode force guide shaft and a welding head clamp; the welding force buffer structure comprises at least one compression spring acting between the welding force transmission structure and the electrode force transmission structure;

the precise electrode force presetting device comprises a precise electrode force presetting structure and an electrode force circuit; the electrode force circuit is electrically connected with the resistance welding power supply so that the electrode force circuit controls the on-off of the welding current;

the welding force breaking device comprises an electromagnet structure and an electromagnet circuit, wherein the electromagnet structure comprises an electromagnet and an adsorption iron block; the electromagnet and the adsorption iron block are respectively arranged on a fixed component and a movable component of the machine head; the movable component is provided with a resetting element which enables the movable component to be reset; the electromagnet circuit is electrically connected with the electromagnet and the electrode force circuit respectively;

the electrode force is maintained and kept relatively constant within a preset range in the whole welding period through the accurate electrode force pressurization system;

2. A resistance welding micro-welding spot welder as claimed in claim 1, characterized in that:

the machine head frame is a plastic machine head frame.

3. A resistance welding micro-welding spot welder according to claim 2, characterized in that:

the connection between the electrode force guide shaft of the plastic machine head frame and the welding head clamp is direct connection of metal and metal.

4. A resistance welding micro-welding spot welder according to claim 3, characterized in that:

the welding head clamp is connected with the electrode force guide shaft through a connecting port formed by butt joint of the welding head clamp fixing part with each arc-shaped interface and the other metal piece in opposite directions at the side edges of each other, so that the sliding shaft sleeve is locked.

5. A resistance welding micro-welding spot welder as claimed in claim 1,

the spot welding machine head is provided with an electric control box, and the electric control box is provided with a structure for feeding electricity to an electric appliance of the machine head.

6. A resistance welding micro-welding spot welder as claimed in claim 5,

the electric control box is provided with a structure for presetting the electric parameter output of the spot welding power supply, and the structure for presetting the electric parameter output comprises a structure preset in a code pulling switch mode or a structure preset in a key mode through a display screen mode.

7. A resistance welding micro-welding spot welder as claimed in claim 1,

the welding head clamp is a step-shaped welding head clamp, the welding head clamp comprises a welding head clamp fixing part, a welding head clamp moving part, a gap between the welding head clamp moving part and the welding head clamp moving part, and an electrode interface, the welding head clamp fixing part is installed on a machine head through connection with a sliding shaft on the machine head, the electrode interface is opened and closed in the direction of the front and rear vertical faces of the machine head or in the direction of the left and right vertical faces of the machine head, and a parallel electrode welding head is installed on the electrode interface.

8. A resistance welding micro-welding spot welder as claimed in claim 7,

an electrode interface is arranged between the movable part and the fixed part of the welding head clamp, stepped bosses are respectively arranged at the top ends of the fixed part and the movable part of the welding head clamp block adjacent to the electrode interface, and an output cable of the spot welding power supply is arranged on the stepped bosses.

9. A resistance welding micro-welding spot welder according to claim 7 or 8,

the electrode interface is arranged at the front side end of the welding head clamp movable part and the welding head clamp fixed part.

10. A resistance welding micro-welding spot welder as claimed in claim 1,

the spot welding machine head and the microscopic optical device are fixedly integrated, the microscopic optical device comprises a microscopic optical bracket and a microscopic optical lens, the microscopic optical lens comprises a stereoscopic microscope head type single-barrel microscope and a CCD camera, and the microscopic optical lens is arranged on the microscopic optical bracket.

11. A resistance welding micro-welding spot welder as claimed in claim 10,

the micro-optical support comprises a cantilever beam fixedly arranged on a machine head frame, a stand column, a cross hole frame, a cross column and a frame with angle and focal length fine adjustment, wherein the stand column, the cross hole frame, the cross column and the frame with angle and focal length fine adjustment are mechanically connected with each other, and a micro-optical lens is arranged on the frame with angle and focal length fine adjustment.