Electrode conversion device and nut projection welding machine comprising same

Abstract

The invention discloses an electrode conversion device and a nut projection welding machine comprising the same. The electrode conversion device comprises a rotating member (1), the rotating member is provided with more than two electrode arm assembly installation parts, the electrode arm assembly installation parts are located at different angle positions of the rotating member, the electrode arm assembly installation parts are used for installing electrode arm assemblies (2), and different electrode arm assemblies are provided with electrodes of the same or different specifications; and the rotation driving mechanism is connected with the rotating part and is used for driving the rotating part to rotate so as to realize switching of the electrode arm assemblies. According to the electrode conversion device, welding of various projection welding nuts can be achieved on one welding device, manual electrode replacement, debugging and the like are not needed, the production efficiency is greatly improved, the number of nut projection welding machines needed by a production line is reduced, and the cost is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of welding equipment, and in particular to an electrode conversion device and a nut projection welding machine including the electrode conversion device. Background Art

[0002] Nut projection welding machines play an extremely important role in the modern vehicle manufacturing industry. This equipment uses the principle of resistance welding to achieve a firm connection between the nut and the body or control cabinet, etc. by applying pressure and current to the welding point at the same time. When the nut projection welding machine is working, the nut is placed in the predetermined position, and then pressure is applied to the nut and the plate through the welding head. Subsequently, the current is passed through the welding area, and the metal is locally heated to a molten state using the principle of resistance heat to complete the welding process. The process of nut projection welding only takes a few seconds, which greatly improves production efficiency. The correct welding parameters can ensure a firm metal connection between the nut and the plate, enhancing the overall stability of the structure. When the welding process is properly controlled, the weld point is flat and smooth, with a beautiful appearance, and no additional surface treatment is required.

[0003] The application advantages of nut projection welding machines include improving production efficiency, reducing production costs, enhancing vehicle safety and strong adaptability. Fast welding speed means completing more production tasks in a shorter time, which is particularly important for mass production. Compared with traditional bolt connections or other complex fixing methods, nut projection welding technology simplifies the production process and reduces material and labor costs. The firm welding of nuts improves the fixing strength of various vehicle components and helps to improve the stability and safety of the vehicle during driving. Nut projection welding machines can be used for welding plates of different materials and thicknesses and have a wide range of applicability.

[0004] Existing nut projection welding machines have many limitations, which seriously restrict production efficiency and product quality. For example, existing nut projection welding machines can only be installed with a pair of upper / lower electrodes, can only adapt to one specification of nuts and one type of stamping opening method, and can only match an automatic conveyor for one specification of nuts. Therefore, when combined into an automatic projection welding line, one process generally requires the use of two nut projection welding machines at the same time to weld nuts of different specifications, which will seriously limit production efficiency.

[0005] Generally speaking, there are 2 to 4 types of nuts distributed on the panels of the body-in-white / frame of a passenger car. The opening directions and sizes of nuts of different specifications are also different when welding. This means that each panel needs to be produced using multiple nut projection welding machines at least at 2 to 4 stations, which requires frequent transportation and buffering of semi-finished products, and multiple loading and unloading of materials at the material frame, making the time required for product transportation and circulation much longer than the welding time, seriously reducing production efficiency. In addition, the production line with multiple welding machines and conveyor lines requires a large area, high investment cost, and requires more operators and high labor costs, which will further affect production efficiency and product quality. Summary of the invention

[0006] In view of this, an embodiment of the present disclosure provides an electrode conversion device and a nut projection welding machine including the electrode conversion device to eliminate or improve one or more defects existing in the prior art.

[0007] The technical solution of the present disclosure is as follows:

[0008] In a first aspect, an electrode conversion device comprises: a rotating member, on which are provided more than two electrode arm assembly mounting parts, each of the electrode arm assembly mounting parts being located at a different angular position of the rotating member, the electrode arm assembly mounting parts being used to mount the electrode arm assembly, and different electrode arm assemblies being installed with electrodes of the same or different specifications; a rotation driving mechanism, the rotation driving mechanism being connected to the rotating member and used to drive the rotation of the rotating member to realize the switching of the electrode arm assembly.

[0009] In some embodiments, the rotary drive mechanism includes a rotational drive source, a hollow spindle, and a first linear actuator;

[0010] The first linear actuator includes a slide cylinder, a first piston, at least one first transmission rod and a closing cover, wherein the closing cover is arranged at one end of the slide cylinder facing the rotating part, the first piston is arranged in the slide cylinder, one end of the first transmission rod is fixedly connected to the first piston, the first transmission rod extends outward from the slide cylinder at the closing cover, and the other end thereof is fixedly connected to the rotating part; the rotation driving source is fixedly connected to the hollow main shaft, the hollow main shaft is fixedly connected to the slide cylinder of the first linear actuator, the slide cylinder is fixedly connected to the closing cover, and the first transmission rod is slidably connected to the closing cover, so that the first transmission rod can not rotate when it is axially translated relative to the closing cover; the rotation driving source drives the hollow main shaft to rotate, thereby driving the slide cylinder, the closing cover and the first transmission rod to rotate, thereby realizing the rotation of the rotating part and the switching of the electrode arm assembly.

[0011] In some embodiments, the electrode conversion device further includes a supporting shell, the first linear actuator is installed in the supporting shell, and an auxiliary supporting structure is provided between the supporting shell and the rotating member for cooperating with the first transmission rod to jointly support the rotating member.

[0012] In some embodiments, the auxiliary support structure includes a first toothed positioning block and a second toothed positioning block, wherein the first toothed positioning block is fixedly arranged on the end surface of the rotating member facing the support shell, and the second toothed positioning block is fixedly arranged on the end surface of the support shell facing the rotating member, and the first toothed positioning block and the second toothed positioning block have mutually engaging positioning tooth surfaces on their facing end surfaces, which are used for positioning and supporting the rotating member; and / or,

[0013] The auxiliary support structure includes at least one set of positioning pins and positioning holes. One of the rotating part and the supporting shell is provided with a positioning pin, and the other corresponding position is provided with a positioning hole. When the rotating part is in the state of non-switching electrode arm assembly, the positioning pin is inserted into the positioning hole to realize the positioning and support of the rotating part.

[0014] In some embodiments, the first toothed positioning block and the second toothed positioning block are annular, arc-shaped or polygonal structures arranged along the circumferential direction, the cross-sectional shape of the positioning teeth of the positioning tooth surface is triangular, trapezoidal or curved arc-shaped, and the top surface shape of the positioning teeth of the positioning tooth surface is fan-shaped, trapezoidal or curved arc-shaped.

[0015] In some embodiments, the supporting shell includes a bearing seat, the bearing seat having a first bearing mounting portion at an end facing the rotating member, for mounting a first bearing, and the slide cylinder of the first linear actuator is rotatably arranged in the bearing seat through the first bearing; the bearing seat has a second bearing mounting portion at an end away from the rotating member, for mounting a second bearing, and the hollow main shaft is rotatably arranged on one side of the bearing seat through the second bearing.

[0016] In some embodiments, the first bearing is a radial bearing, the inner ring of the first bearing is connected to the outer circumferential surface of the slide cylinder, and the outer ring of the first bearing is connected to the bearing seat;

[0017] The second bearing is an axial bearing, the inner ring of the second bearing is connected to the end surface of the hollow main shaft, and the outer ring of the second bearing is connected to the bearing seat.

[0018] In some embodiments, the first piston of the first linear actuator can be driven to move axially, so as to promote the axial movement of the rotating member through the first transmission rod; in the switching state of the electrode arm assembly, the rotating member is configured to extend so that the auxiliary support structure is separated; in the non-switching state, the rotating member is configured to retract so that the auxiliary support structure is combined to realize the positioning and support of the rotating member; and / or,

[0019] A first elastic member is arranged in the slide cylinder of the first linear actuator, and two ends of the first elastic member respectively abut against the closing cover and the first piston, and are used for resetting the first piston, the first transmission rod and the rotating member.

[0020] In some embodiments, the rotary drive mechanism further comprises a second linear actuator for locking the rotating member to prevent axial movement thereof;

[0021] The second linear actuator comprises a cylinder body and a second piston disposed in the cylinder body, and the second piston can be driven to move axially;

[0022] The first linear actuator further includes a second transmission rod, one end of which is fixedly connected to a side of the first piston away from the first transmission rod, and the second transmission rod extends into the cylinder body of the second linear actuator;

[0023] Wherein, the second piston is provided with a locking structure on a side facing the second transmission rod, which is used to lock the second transmission rod, thereby locking the first piston, the first transmission rod and the rotating part to prevent their axial movement.

[0024] In some embodiments, when the electrode arm assembly is in a welding state, the second linear actuator is configured to lock the rotating member; when the electrode arm assembly is in a switching state, the second linear actuator is configured to unlock the rotating member; and / or,

[0025] A second elastic member is disposed in the cylinder body of the second linear actuator, and two ends of the second elastic member respectively abut against the end surface of the second piston away from the second transmission rod and the cylinder body, so as to lock the second transmission rod by its own elasticity; and / or,

[0026] The locking structure of the second piston is a flared groove, and the second transmission rod is formed with an annular groove on the shaft section extending into the flared groove, and a plurality of balls are arranged in the annular groove. The axial movement of the second piston causes the side wall of the flared groove to press or loosen the balls in the annular groove to achieve locking or unlocking.

[0027] In some embodiments, the first linear actuator and the second linear actuator are hydraulic cylinders, pneumatic cylinders or linear motors; and / or,

[0028] The first linear actuator and the second linear actuator are single-acting cylinders, and the electrode conversion device is equipped with an air source and a rotary air distribution structure, and the air source supplies air to the first linear actuator and the second linear actuator through the rotary air distribution structure;

[0029] Wherein, the rotary air distribution structure comprises a first air supply pipeline, a second air supply pipeline and a pneumatic control pipeline located in the hollow main shaft;

[0030] The first air supply pipeline is connected to the cavity of the slide cylinder of the first linear actuator away from the rotating member, and is used to extend the rotating member when air is supplied;

[0031] The second air supply pipeline is connected to the cavity of the cylinder body of the second linear actuator close to the rotating member, and is used to unlock the rotating member when air is supplied;

[0032] The pneumatic control pipeline is connected to the cavity of the cylinder of the second linear actuator away from the rotating member, and is used to set a logic valve to achieve sequential action logic control of the first linear actuator and the second linear actuator.

[0033] In some embodiments, a first reversing valve is disposed on the first air supply pipeline, and the first reversing valve has an exhaust port for pressure relief;

[0034] The second air supply pipeline is provided with a second reversing valve, and the second reversing valve has an exhaust port for pressure relief;

[0035] The logic valve includes a dual-pressure valve and a shuttle valve, which are used to control the first linear actuator and the second linear actuator to realize the action sequence of "second linear actuator unlocking→first linear actuator extending→rotating member rotating→first linear actuator retracting→second linear actuator locking".

[0036] In some embodiments, the electrode arm assembly includes an electrode and an electrode support, and the electrode support is L-shaped or extends outwardly, so that the electrode is located outside the axial projection of the rotating member; and / or,

[0037] The connection of the electrode arm assembly on the rotating member is a detachable connection or a position-adjustable connection; and / or,

[0038] The number of the electrode arm assemblies is set to 2-10, and they are evenly or unevenly arranged on the rotating member; and / or,

[0039] The electrode shape of each electrode arm assembly matches nuts of different specifications; and / or,

[0040] The supporting shell further comprises a fixed rear seat, wherein the hollow main shaft is arranged in the rear seat; and / or,

[0041] The rotary drive source further includes a reducer, which is at least one of a planetary gear reducer, a cycloid pinwheel reducer, an RV reducer, a conical friction transmission reducer and a worm reducer; and / or,

[0042] The rotation driving source is a pneumatic rotary motor, a hydraulic rotary motor or an electric motor.

[0043] In a second aspect, the present disclosure also provides a nut projection welding machine, comprising the above-mentioned electrode conversion device.

[0044] After the electrode conversion device and the nut projection welding machine in the disclosed embodiments are industrialized, during the production process, no matter it is projection welding of nuts of different specifications on the same plate or projection welding of nuts of different specifications on different plates, there is no need for manual participation in replacing electrodes and debugging parameters, which can greatly shorten the mold change time, realize small batch flexible production, greatly improve production efficiency, greatly reduce the number of operators, greatly reduce the floor space, and greatly reduce production costs.

[0045] Additional advantages, purposes, and features of the present disclosure will be described in part in the following description, and will become apparent to those of ordinary skill in the art after studying the following, or may be learned from the practice of the present disclosure. The purposes and other advantages of the present disclosure may be achieved and obtained by the structures specifically indicated in the written description and claims and the accompanying drawings.

[0046] Those skilled in the art will understand that the objectives and advantages that can be achieved by the present disclosure are not limited to the above specific description, and the above and other objectives that can be achieved by the present disclosure will be more clearly understood from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings described herein are used to provide a further understanding of the present disclosure, constitute a part of the present application, and do not constitute a limitation of the present disclosure. The drawings are only for illustrating the principles of the present disclosure, and the actual structure may vary due to factors such as process and cost. In order to facilitate the illustration and description of some parts of the present disclosure, the corresponding parts in the drawings may be enlarged, that is, they may become larger relative to other parts in the exemplary device actually manufactured according to the present disclosure. In the drawings:

[0048] Figure 1 It is a cross-sectional view of a partial structure of an electrode conversion device in one embodiment of the present disclosure.

[0049] Figure 2 1 is a side view of an electrode conversion device in an embodiment of the present disclosure.

[0050] Figure 3 for Figure 1 A partial enlarged schematic diagram of .

[0051] Figure 4 1 is a pneumatic principle diagram of an electrode conversion device in one embodiment of the present disclosure.

[0052] Reference numerals:

[0053] 1. Rotating parts;

[0054] 2. electrode arm assembly; 21. electrode; 22. electrode bracket;

[0055] 3. Rotation driving source; 31. Motor; 32. Speed ​​reducer;

[0056] 41. Hollow spindle;

[0057] 42, first linear actuator; 421, slide cylinder; 422, closing cover; 423, first piston; 424, first transmission rod; 425, first elastic member; 426, second transmission rod;

[0058] 43. Second linear actuator; 431. Cylinder body; 432. Second piston; 433. Second elastic member;

[0059] 441, flared groove; 442, annular groove; 443, sphere;

[0060] 51. first tooth-shaped positioning block; 52. second tooth-shaped positioning block; 53. bearing seat; 54. first bearing; 55. second bearing; 56. rear seat; 57. motor mounting seat;

[0061] 61. First air supply pipeline; 62. Second air supply pipeline; 63. Pneumatic control pipeline;

[0062] 71. First reversing valve; 72. Second reversing valve; 73. Double pressure valve; 74. Shuttle valve. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the present disclosure more clear, the present disclosure is further described in detail below in combination with the embodiments and the accompanying drawings. Here, the illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure, but are not intended to limit the present disclosure.

[0064] It should also be noted here that in order to avoid obscuring the present disclosure due to unnecessary details, only structures and / or processing steps closely related to the scheme according to the present disclosure are shown in the accompanying drawings, while other details that are not closely related to the present disclosure are omitted.

[0065] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0066] It should also be noted that, unless otherwise specified, the term “connection” herein may refer not only to a direct connection but also to an indirect connection involving an intermediate.

[0067] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0068] The present invention provides an electrode conversion device and a nut projection welding machine including the electrode conversion device, which can realize the welding of various projection welding nuts on a single welding device without the need for manual participation in electrode replacement and debugging, thereby greatly improving production efficiency and reducing the number of nut projection welding machines required for the production line, thereby reducing costs.

[0069] It can be understood that the "nut" in the so-called "nut projection welding equipment / nut projection welding machine" or "projection welding nut" is a continuation of the traditional naming. In fact, it not only includes nuts connected to plates using the projection welding process, but also includes other fasteners connected to plates using the projection welding process, including studs, bolts and pins.

[0070] In a first aspect, the present disclosure provides an electrode conversion device, such as Figures 1 to 3 As shown, the electrode conversion device includes a rotating member 1 and a rotation driving mechanism.

[0071] Wherein, the rotating part is provided with more than two electrode arm assembly mounting parts, each of which is located at a different angular position of the rotating part, and the electrode arm assembly mounting part is used to mount the electrode arm assembly 2, and different electrode arm assemblies 2 are mounted with electrodes of the same or different specifications. The different angular positions of the rotating part here refer to different points on the arc that can be marked by degrees, where 0 degrees is usually the starting point of the arc, and different angular positions can also refer to whether the electrode arm assembly mounting part or the electrode arm assembly 2 is distributed in the circumferential direction of the rotating part.

[0072] The rotary drive mechanism is connected to the rotating member 1 and is used to drive the rotating member 1 to rotate so as to switch the electrode arm assembly 2. Different electrode arm assembly mounting parts can be installed with electrode arm assemblies 2 of the same specification. When one electrode arm assembly 2 fails, another electrode arm assembly 2 is switched to perform normal processing to avoid affecting the processing progress; different electrode arm assembly mounting parts can be installed with electrode arm assemblies 2 of different specifications to weld nuts of different specifications.

[0073] In order to realize the one-time welding of nuts of all specifications and stamping parts of all shapes and sizes using a nut projection welding machine, the electrode conversion device of the embodiment of the present invention is integrated with part or all of the electrode arm assemblies 2 of the required specifications on the rotating part 1. When welding nuts of a certain specification on a certain stamping part shape and size, the rotary drive mechanism quickly rotates the rotating part 1 to switch the required upper / lower electrodes to the working position with sufficiently high accuracy, while ensuring that the device can maintain sufficiently high rigidity when subjected to a sufficiently large load.

[0074] It is understandable that the nut projection welding machine is a device specially used to fix nuts and metal plates by welding. This machine achieves welding by generating a strong current between the upper and lower electrodes and using the heat generated by the current to melt the contact part of the nut and the plate. The welding head is the core part of the nut projection welding machine, which includes an upper electrode and a lower electrode. The upper electrode can be designed to be movable to align and press the nut to be welded; the lower electrode is fixed to support the metal plate. The above-mentioned electrode conversion device can be used to install several upper electrode arm assemblies, and can also be used to install several lower electrode arm assemblies. Optionally, the upper and lower electrode arm assemblies are connected using an electrode conversion device, and the conversion and use of the upper and lower electrode arm assemblies should be matched, that is, suitable for projection welding nuts of the same specification.

[0075] In some embodiments, the electrode conversion device uses a rotary switching electrode method. Figure 1 As shown, the rotary drive mechanism includes a rotary drive source 3, a hollow main shaft 41 and a first linear actuator 42. The first linear actuator 42 can not only be used to perform linear motion, but also can be used as a transmission structure for rotary drive.

[0076] Specifically, the first linear actuator 42 may include a slide 421, a first piston 423, at least one first transmission rod 424, and a closing cover 422. The closing cover 422 is disposed at one end of the slide 421 facing the rotating member 1, the first piston 423 is disposed in the slide 421, one end of the first transmission rod 424 is fixedly connected to the first piston 423, the first transmission rod 424 extends outward from the slide 421 at the closing cover 422, and the other end thereof is fixedly connected to the rotating member 1.

[0077] Further, as a feasible method, the first piston 423 and the first transmission rod 424 (including the second transmission rod 426 described below) described herein can form a piston assembly, and the connection relationship thereof can adopt the piston assembly in the prior art, and has sufficient strength, rigidity and stability; the connection between the first transmission rod 424 and the rotating member 1 can be fixedly installed with the help of the threaded structure and the round nut at the end of the connecting rod. When the first transmission rod 424 is provided with one, the connection between the first transmission rod 424 and the rotating member 1 also adopts a key connection to ensure the transmission of the rotational torque; but it is not limited to this, and it can also be a flange connection, etc.

[0078] In another possible implementation, a plurality of first transmission rods 424 are provided, and the first transmission rods 424 are arranged parallel to each other, for example, evenly distributed around the center line of the first piston; when a plurality of first transmission rods 424 are used, the connection between the first transmission rods 424 and the closing cover 422 does not require the use of a guide flat key to transmit torque, and the connection between the plurality of first transmission rods 424 and the rotating member 1 does not require a flat key; more than two first transmission rods 424 are distributed at multiple points on the closing cover 422 and the rotating member 1, and torque transmission can be achieved by only a plug-in relationship.

[0079] As a connection relationship of the rotational drive mode, the installation mode of the first linear actuator 42 adopts a rotatable support. The rotational drive source 3 is fixedly connected to the hollow main shaft 41, the hollow main shaft 41 is fixedly connected to the slide 421 of the first linear actuator 42, the slide 421 is fixedly connected to the closing cover 422, and the first transmission rod 424 is slidably connected to the closing cover 422, so that the first transmission rod 424 can be axially translated relative to the closing cover 422 without rotating, that is, the first transmission rod 424 can be axially translated relative to the closing cover 422 without rotating. The fixed connection described here can be a threaded connector, etc., and the sliding connection between the first transmission rod 424 and the closing cover 422 can be a key connection, such as a flat key or a spline, but is not limited to this, and other sliding connection methods can also be used.

[0080] In the above embodiment, the rotation driving source 3 drives the hollow main shaft 41 to rotate, thereby driving the slide 421, the closing cover 422 and the first transmission rod 424 to rotate, thereby realizing the rotation of the rotating part 1 and the switching of different electrode arm assemblies 2, and different specifications of projection welding electrodes can be used on a nut projection welding machine.

[0081] In some embodiments, the electrode conversion device further includes a support shell, the first linear actuator 42 is installed in the support shell, and an auxiliary support structure is provided between the support shell and the rotating member 1, which is used to cooperate with the first transmission rod 424 to support the rotating member 1. The support shell can provide two functions, not only providing rotation support for the first linear actuator 42, but also providing auxiliary support for the rotating member 1. Optionally, in the case where there is only one first transmission rod 424, the first transmission rod 424 of the first linear actuator 42 is connected to the central part of the rotating member 1, and only the first transmission rod 424 provides support and torque for the rotating member 1, which puts forward requirements for the design of the first transmission rod 424. Therefore, the support shell can also be used to provide certain support at the non-central part of the rotating member 1 with the help of the auxiliary support structure to prevent the rotating member 1 from overturning when a certain pressure is applied to the plate. When multiple first transmission rods 424 are used, the first transmission rods 424 are generally evenly distributed around the circumference of the center line of the first piston. At this time, although the torque and thrust borne by each first transmission rod 424 are relatively dispersed, an auxiliary support structure can also be provided.

[0082] Furthermore, if Figure 1 As shown, as an implementable method, the auxiliary support structure includes a first tooth-shaped positioning block 51 and a second tooth-shaped positioning block 52. Among them, the first tooth-shaped positioning block 51 is fixedly arranged on the end face of the rotating member 1 facing the support shell, and the second tooth-shaped positioning block 52 is fixedly arranged on the end face of the support shell facing the rotating member 1. The first tooth-shaped positioning block 51 and the second tooth-shaped positioning block 52 have mutually engaging positioning tooth surfaces on the end faces facing each other, which are used for positioning and supporting the rotating member 1. The first pressing block described here can be integrally formed with the rotating member 1, or can be a later fixed connection setting, such as welding or threaded connection, etc. The connection between the second pressing block and the support shell can also be integrally formed or other fixed connection settings. However, it is not limited to this. The connection between the first tooth-shaped positioning block 51 and the second tooth-shaped positioning block 52 can also be a detachable connection, so that the entire tooth block can be replaced after the positioning tooth surface is worn. Optionally, the positioning tooth surface is a precision positioning tooth, which not only has a supporting function, but also has a positioning function, so that the electrode welding position is more accurate. The rotating part 1 is slightly extended before rotating, and is retracted after rotating into position so that the teeth are meshed together, thereby ensuring high precision and high rigidity of the rotating part 1 under radial and axial high load conditions.

[0083] In the above embodiment, the first toothed positioning block 51 and the second toothed positioning block 52 are annular, arc-shaped or polygonal structures arranged along the circumferential direction, and the cross-sectional shape of the positioning tooth (single) of the positioning tooth surface is a triangle, a trapezoid or other shapes composed of curves. The top surface shape of the positioning tooth of the positioning tooth surface is a fan-shaped, a trapezoid or other shapes composed of curves. The cross-sectional shape and the top surface shape of the positioning tooth have different structural characteristics and applicable scenarios, and the selection of its specific tooth type can be selected according to factors such as axial radial load, material and different processing standards. Optionally, the distribution shape of the positioning tooth surface of the first toothed positioning block 51 and the second toothed positioning block 52 on the tooth block is a closed ring of the entire circumference to increase the force and support area.

[0084] As another possible implementation, the auxiliary support structure includes at least one set of positioning pins and positioning holes, one of the rotating member 1 and the supporting shell is provided with a positioning pin, and the other corresponding position is provided with a positioning hole, and when the rotating member 1 is in a state of not switching the electrode arm assembly 2, the positioning pin is inserted into the positioning hole to achieve positioning and support of the rotating member 1. In this implementation, the positioning pin can be optionally integrally formed on the rotating member 1 or the supporting shell.

[0085] In some embodiments, the first piston 423 of the first linear actuator 42 can be driven to move axially, so as to promote the axial movement of the rotating member 1 through the first transmission rod 424; in the switching state of the electrode arm assembly 2, the rotating member 1 is configured to extend so that the auxiliary support structure is separated; in the non-switching state, the rotating member 1 is configured to retract so that the auxiliary support structure is combined to achieve the positioning and support of the rotating member 1.

[0086] Furthermore, a first elastic member 425 is provided in the slide cylinder 421 of the first linear actuator 42, and the two ends of the first elastic member 425 respectively abut against the closing cover 422 and the first piston 423, and are used for resetting the first piston 423, the first transmission rod 424 and the rotating member 1. The first elastic member 425 described here can be a spring, and the first elastic member 425 is also conducive to the rotating member 1 to always keep the auxiliary support structure in a locked state, and the locking situation will not occur even if the factory is powered off or the gas is cut off, which fully ensures the safe operation of the equipment.

[0087] In some embodiments, Figure 1 and Figure 3As shown, in order to realize the rotatable support of the first linear actuator 42, the support shell includes a bearing seat 53, and the bearing seat 53 has a first bearing mounting portion at the end facing the rotating member 1, for mounting a first bearing 54, and the slide cylinder 421 of the first linear actuator 42 is rotatably arranged in the bearing seat 53 through the first bearing 54; the bearing seat 53 has a second bearing mounting portion at the end away from the rotating member 1, for mounting a second bearing 55, and the hollow main shaft 41 is rotatably arranged on one side of the bearing seat 53 through the second bearing 55.

[0088] In the above embodiment, the axial limit of the first bearing 54 can be achieved by the step portion of the first bearing mounting portion and the closing cover 422, that is, the diameter of the closing cover 422 is larger than the diameter of the slide cylinder 421 of the first linear actuator 42, and the closing cover 422 not only achieves the cavity sealing function of the slide cylinder 421 of the first linear actuator 42, but also achieves the cavity sealing function of the bearing seat 53. Optionally, the outer peripheral surface of the closing cover 422 is provided with a sealing groove and a sealing ring to prevent external dust from entering the interior of the bearing seat 53.

[0089] Furthermore, the first bearing 54 is a radial bearing, which is mainly used to bear the load perpendicular to the axis direction. For example, deep groove ball bearings, tapered roller bearings, cylindrical roller bearings, angular contact ball bearings and sliding bearings can be used; the inner ring of the first bearing 54 is connected to the outer peripheral surface of the slide cylinder 421, and the outer ring of the first bearing 54 is connected to the bearing seat 53; the connection described here is generally a tight fit connection, which means that their size and geometry are precisely designed to ensure that the inner ring, the outer ring and their matching installation structure have a certain degree of tightness, can rotate freely and bear loads.

[0090] In the above embodiment, the axial limit of the second bearing 55 can be achieved by the step portion of the second bearing mounting portion and the hollow main shaft 41. The second bearing 55 has a certain gap (not in direct contact) with the slide cylinder 421 of the first linear actuator 42. The second bearing 55 is an axial bearing (also called a thrust bearing), which is specially used to bear axial loads (also called thrust loads). The second bearing 55 can be a ball thrust bearing, a roller thrust bearing, a tapered roller thrust bearing or a sliding thrust bearing, etc.; the inner ring of the second bearing 55 is connected to the end face of the hollow main shaft 41, and the outer ring of the second bearing 55 is connected to the bearing seat 53.

[0091] In order to ensure the high reliability and high safety of the electrode conversion device, Figure 1 and Figure 3 As shown, the rotary drive mechanism further includes a second linear actuator 43 for locking the rotating member 1 to prevent the rotating member 1 from axial movement. The second linear actuator 43 is arranged on a side of the first linear actuator 42 away from the rotating member 1 .

[0092] The second linear actuator 43 includes a cylinder body 431 and a second piston 432 disposed in the cylinder body 431, and the second piston 432 can be driven to move axially. The first linear actuator 42 also includes a second transmission rod 426, one end of which is fixedly connected to the side of the first piston 423 away from the first transmission rod 424, and the second transmission rod 426 extends into the cylinder body 431 of the second linear actuator 43; wherein the second piston 432 is provided with a locking structure on the side facing the second transmission rod 426, which is used to lock the second transmission rod 426, thereby locking the first piston 423, the first transmission rod 424 and the rotating member 1 to prevent them from moving axially.

[0093] In the above embodiment, when the electrode arm assembly 2 is in a welding state, the second linear actuator 43 is configured to lock the rotating member 1; when the electrode arm assembly 2 is in a switching state, the second linear actuator 43 is configured to unlock the rotating member 1.

[0094] Furthermore, a second elastic member 433 is provided in the cylinder body 431 of the second linear actuator 43, and both ends of the second elastic member 433 respectively abut against the end surface of the second piston 432 away from the second transmission rod 426 and the cylinder body 431, so as to lock the second transmission rod 426 by its own elasticity; the second elastic member 433 described here can be a spring, and the second elastic member 433 is also conducive to the rotating member 1 always keeping the locked state, and the locking state will not occur even if the factory loses power or gas, thereby fully ensuring the safe operation of the equipment.

[0095] like Figure 3 As shown, as an implementable manner of the locking structure, the locking structure of the second piston 432 is a flared groove 441, and the side wall of the flared groove 441 can be an inclined surface or an arc surface; the second transmission rod 426 is formed with an annular groove 442 on the shaft section extending into the flared groove 441, and a plurality of balls 443 are arranged in the annular groove 442, and the balls 443 can be steel balls. The axial movement of the second piston 432 causes the side wall of the flared groove 441 to press or loosen the balls 443 in the annular groove 442, thereby achieving locking or unlocking. The locking structure can also be implemented in other structures.

[0096] In the above embodiment, the first linear actuator 42 and the second linear actuator 43 can be hydraulic cylinders, air cylinders or linear motors 31, etc., which can perform linear motion. The linear motion of the first linear actuator 42 is used to lift and retract the rotating part 1 so that it can switch the electrode arm assembly 2; the linear motion of the second linear actuator 43 is used to lock and unlock the connecting rod of the first linear actuator 42 to lock and unlock the rotating part 1, ensuring the reliable operation of the equipment and improving the safety. A second linear actuator 43 is set at the rear end of the first linear actuator 42 to provide a sufficiently large axial locking force to the surface teeth, thereby ensuring that the rotating part 1 has a sufficiently high precision and a sufficiently large anti-tilting moment during welding.

[0097] Furthermore, the first linear actuator 42 and the second linear actuator 43 are single-acting cylinders (which may be respectively referred to as clutch cylinders and locking cylinders), and their return motion may be performed with the aid of elastic members, and have a simple structure and are less prone to failure.

[0098] Furthermore, the electrode conversion device is equipped with an air source and a rotary air distribution structure, and the air source supplies air to the first linear actuator 42 and the second linear actuator 43 through the rotary air distribution structure. The two cylinders inside the hollow main shaft 41 supply air through the rotary air distribution structure, so that the rotating part 1 can achieve infinite rotation, so that when switching electrodes, it can always rotate quickly to the position in the shortest path without worrying about pipeline entanglement.

[0099] like Figure 1 , Figure 3 and Figure 4 As shown, the rotary air distribution structure includes a first air supply pipeline 61, a second air supply pipeline 62 and a pneumatic control pipeline 63 located in the hollow main shaft 41. The first air supply pipeline 61 is connected to the cavity of the slide cylinder 421 of the first linear actuator 42 away from the rotating member 1, and is used to extend the rotating member 1 when air is supplied; the second air supply pipeline 62 is connected to the cavity of the cylinder body 431 of the second linear actuator 43 close to the rotating member 1, and is used to unlock the rotating member 1 when air is supplied.

[0100] The pneumatic control pipeline 63 is connected to the cavity of the cylinder 431 of the second linear actuator 43 away from the rotating member 1 and is used to set a logic valve to achieve sequential action logic control of the first linear actuator 42 and the second linear actuator 43 .

[0101] like Figure 4As shown, the first air supply pipeline 61 is provided with a first reversing valve 71, which has an exhaust port for pressure relief; the second air supply pipeline 62 is provided with a second reversing valve 72, which has an exhaust port for pressure relief; the logic valve includes a dual-pressure valve 73 and a shuttle valve 74, the dual-pressure valve 73 is linked with the first reversing valve 71, and the shuttle valve 74 is linked with the second reversing valve 72; it is used to control the first linear actuator 42 and the second linear actuator 43 to realize the action sequence of "the second linear actuator 43 is unlocked → the first linear actuator 42 extends → the rotating member 1 rotates → the first linear actuator 42 retracts → the second linear actuator 43 is locked". In this embodiment, the action of the two cylinders can be controlled by two air-controlled reversing valves and two logic valves, ensuring that their action sequence is logical, solving the problem of state detection and signal transmission of the two cylinders in the spindle when the solenoid valve is controlled.

[0102] When the main control air circuit is supplied with air, the second reversing valve 72 is firstly reversed through the shuttle valve 74, and the second piston 432 moves in the direction away from the rotating member 1 under the drive of air pressure. The flared groove on the second piston 432 no longer compresses the locking steel ball, and the locking steel ball no longer locks the second transmission rod 426. The second linear actuator 43 is in an unlocked state at this time. At this time, the pneumatic control line 63 is blocked to form a high air pressure, thereby reversing the first reversing valve 71 through the logic valve together with the main control air circuit, so that the first air supply line 61 pushes the first piston 423 to compress the first elastic member 425 to move in the direction facing the rotating member 1, thereby extending the rotating member 1 and the first transmission rod 424 together.

[0103] When the rotating part 1 is not welded, the spring of the first linear actuator 42 (clutch cylinder) provides the tension to tighten the rotating part 1 to a pair of facing teeth. At this time, the hollow main shaft 41 is subjected to a small axial force. When the equipment is welded, the electrode is subjected to a large radial force (this radial force can be borne by the facing teeth), causing the rotating part 1 to be subjected to a large overturning moment. At this time, the second linear actuator 43 (locking cylinder) is required to provide a large axial force to resist this overturning moment. When the locking cylinder provides this axial force, the thrust bearing and a pair of facing teeth of the hollow main shaft 41 are under pressure, that is, the thrust bearing bears the axial force.

[0104] like Figure 1 and Figure 2As shown, as an implementable manner, the electrode arm assembly 2 includes an electrode 21 and an electrode holder 22, and the electrode holder 22 is L-shaped or extends outward, so that the electrode 21 is located outside the axial projection of the rotating member 1, which is convenient for the execution of the welding action. The electrode holder 22 can be connected to the rotating member 1 using bolts or the like. Furthermore, the connection of the electrode arm assembly 2 on the rotating member 1 is a detachable connection or a position-adjustable connection, so that the electrode conversion device covers a wider range of machinable parts.

[0105] As an implementable manner, the number of the electrode arm assemblies 2 is set to 2-10, which are evenly or unevenly arranged on the rotating part 1; the electrode shape of each electrode arm assembly 2 matches nuts of different specifications; further, each rotating part 1 is installed with 4, 5 or 6 sets of electrode arm assemblies 2 that are equally divided and arranged in the shape of a plane center ray.

[0106] As an implementable manner, the support housing further comprises a fixed rear seat 56, the hollow main shaft 41 is arranged in the rear seat 56, and the rear seat 56 is used to provide rotation support for the hollow main shaft 41. Optionally, a plurality of sealing rings may also be arranged between the rear seat 56 and the hollow main shaft 41. The rear seat 56 may also be fixedly provided with a motor mounting seat 57 for mounting the rotation drive source 3.

[0107] As an implementable manner, the rotation driving source 3 further includes a reducer 32, and the reducer 32 is at least one of a planetary gear reducer, a cycloidal pinwheel reducer, an RV reducer, a conical friction transmission reducer, and a worm reducer. The rotation driving source 3 is a pneumatic rotary motor, a hydraulic rotary motor, or a motor 31. For example, the rotation driving source 3 is driven by an AC servo motor 31 through an RV reducer to ensure that the indexing can be completed quickly and accurately.

[0108] In a second aspect, the embodiment of the present disclosure also provides a nut projection welding machine, including the above-mentioned electrode conversion device. The nut projection welding machine can also be other welding machines, such as a spot welding machine.

[0109] Compared with the existing nut projection welding machines which can only install a pair of upper and lower electrode structures, the present invention can simultaneously install upper electrodes and lower electrodes of various specifications. Through combined use, the electrode switching can be automatically and quickly completed without human intervention, and can meet the needs of more than 95% of the panel nut projection welding in the body-in-white stamping parts factory.

[0110] The present invention creatively arranges two single-acting clutch cylinders and locking cylinders in the hollow spindle, so that the rotating part can be extended and locked in the spindle, and together with the precision positioning surface teeth, the rotating part is provided with high precision and high rigidity, and can withstand the impact load caused by sufficiently large welding pressure. In addition, the present invention adopts an AC servo motor to drive the spindle and the rotating part to change positions through a planetary reducer, so that the electrode switching is accurate and rapid, meeting the requirements of highly humanized production.

[0111] After the electrode conversion device and the nut projection welding machine in the disclosed embodiments are industrialized, during the production process, no matter it is projection welding of nuts of different specifications on the same plate or projection welding of nuts of different specifications on different plates, there is no need for manual participation in replacing electrodes and debugging parameters, which can greatly shorten the mold change time, realize small batch flexible production, greatly improve production efficiency, greatly reduce the number of operators, greatly reduce the floor space, and greatly reduce production costs.

[0112] In the present disclosure, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or replace features of other embodiments.

[0113] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. For those skilled in the art, the embodiments of the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. An electrode conversion device, characterized in that: The electrode conversion device comprises: A rotating member (1), wherein the rotating member is provided with two or more electrode arm assembly mounting parts, each of the electrode arm assembly mounting parts is located at a different angular position of the rotating member, and the electrode arm assembly mounting parts are used to mount an electrode arm assembly (2), and different electrode arm assemblies (2) are mounted with electrodes of the same or different specifications; A rotary drive mechanism, the rotary drive mechanism is connected to the rotating member (1) and is used to drive the rotating member (1) to rotate so as to achieve the switching of the electrode arm assembly (2).

2. The electrode conversion device according to claim 1, characterized in that: The rotary drive mechanism comprises a rotary drive source (3), a hollow main shaft (41) and a first linear actuator (42); The first linear actuator (42) comprises a slide cylinder (421), a first piston (423), at least one first transmission rod (424) and a closing cover (422), wherein the closing cover (422) is arranged at one end of the slide cylinder (421) facing the rotating member (1), the first piston (423) is arranged in the slide cylinder (421), one end of each first transmission rod (424) is fixedly connected to the first piston (423), and the first transmission rod (424) extends outward from the slide cylinder (421) at the closing cover (422), and the other end thereof is fixedly connected to the rotating member (1); The rotation drive source (3) is fixedly connected to the hollow main shaft (41), the hollow main shaft (41) is fixedly connected to the slide cylinder (421) of the first linear actuator (42), the slide cylinder (421) is fixedly connected to the closing cover (422), and the first transmission rod (424) is slidably connected to the closing cover (422), so that the first transmission rod (424) can be axially translated relative to the closing cover (422) without rotating; The rotation driving source (3) drives the hollow main shaft (41) to rotate, thereby driving the slide cylinder (421), the closing cover (422) and the first transmission rod (424) to rotate, thereby realizing the rotation of the rotating member (1) and the switching of the electrode arm assembly (2).

3. The electrode conversion device according to claim 2, characterized in that: The electrode conversion device also includes a support shell, the first linear actuator (42) is installed in the support shell, and an auxiliary support structure is provided between the support shell and the rotating member (1) for cooperating with the first transmission rod (424) to jointly support the rotating member (1).

4. The electrode conversion device according to claim 3, characterized in that: The auxiliary support structure comprises a first toothed positioning block (51) and a second toothed positioning block (52), wherein the first toothed positioning block (51) is fixedly arranged on the end surface of the rotating member (1) facing the support shell, and the second toothed positioning block (52) is fixedly arranged on the end surface of the support shell facing the rotating member (1), and the first toothed positioning block (51) and the second toothed positioning block (52) have mutually engaging positioning tooth surfaces on their facing end surfaces, and are used for positioning and supporting the rotating member (1); and / or, The auxiliary support structure comprises at least one set of positioning pins and positioning holes, wherein one of the rotating member (1) and the supporting shell is provided with a positioning pin, and the other corresponding position is provided with a positioning hole, and when the rotating member (1) is in a state of not switching the electrode arm assembly (2), the positioning pin is inserted into the positioning hole to achieve positioning and support of the rotating member (1).

5. The electrode conversion device according to claim 4, characterized in that: The first tooth-shaped positioning block (51) and the second tooth-shaped positioning block (52) are annular, arc-shaped or polygonal structures arranged along the circumferential direction, the cross-sectional shape of the positioning teeth of the positioning tooth surface is a triangle, a trapezoid or a curved arc, and the top surface shape of the positioning teeth of the positioning tooth surface is a fan-shaped, a trapezoid or a curved arc.

6. The electrode conversion device according to claim 3, characterized in that: The supporting shell includes a bearing seat (53), and the bearing seat (53) has a first bearing mounting portion at an end facing the rotating member (1), for mounting a first bearing (54), and the slide cylinder (421) of the first linear actuator (42) is rotatably arranged in the bearing seat (53) through the first bearing (54); the bearing seat (53) has a second bearing mounting portion at an end away from the rotating member (1), for mounting a second bearing (55), and the hollow main shaft (41) is rotatably arranged on one side of the bearing seat (53) through the second bearing (55).

7. The electrode conversion device according to claim 6, characterized in that: The first bearing (54) is a radial bearing, the inner ring of the first bearing (54) is connected to the outer peripheral surface of the slide cylinder (421), and the outer ring of the first bearing (54) is connected to the bearing seat (53); The second bearing (55) is an axial bearing, the inner ring of the second bearing (55) is connected to the end surface of the hollow main shaft (41), and the outer ring of the second bearing (55) is connected to the bearing seat (53).

8. The electrode conversion device according to claim 4, characterized in that: The first piston (423) of the first linear actuator (42) can be driven to move axially, so as to promote the axial movement of the rotating member (1) through the first transmission rod (424); in the switching state of the electrode arm assembly (2), the rotating member (1) is configured to extend so that the auxiliary support structure is separated; in the non-switching state, the rotating member (1) is configured to retract so that the auxiliary support structure is combined to achieve the positioning and support of the rotating member (1); and / or, A first elastic member (425) is arranged in the slide cylinder (421) of the first linear actuator (42), and two ends of the first elastic member (425) respectively abut against the closing cover (422) and the first piston (423) to reset the first piston (423), the first transmission rod (424) and the rotating member (1).

9. The electrode conversion device according to claim 8, characterized in that: The rotary drive mechanism further comprises a second linear actuator (43) for locking the rotating member (1) to prevent the rotating member (1) from axial movement; The second linear actuator (43) comprises a cylinder body (431) and a second piston (432) disposed in the cylinder body (431), and the second piston (432) can be driven to move axially; The first linear actuator (42) further comprises a second transmission rod (426), one end of the second transmission rod (426) being fixedly connected to a side of the first piston (423) facing away from the first transmission rod (424), and the second transmission rod (426) extending into a cylinder body (431) of the second linear actuator (43); The second piston (432) is provided with a locking structure on the side facing the second transmission rod (426) for locking the second transmission rod (426), thereby locking the first piston (423), the first transmission rod (424) and the rotating member (1) to prevent axial movement thereof.

10. The electrode conversion device according to claim 9, characterized in that: When the electrode arm assembly (2) is in a welding state, the second linear actuator (43) is configured to lock the rotating member (1); when the electrode arm assembly (2) is in a switching state, the second linear actuator (43) is configured to unlock the rotating member (1); and / or, A second elastic member (433) is arranged in the cylinder body (431) of the second linear actuator (43), and two ends of the second elastic member (433) respectively abut against the end surface of the second piston (432) away from the second transmission rod (426) and the cylinder body (431), so as to lock the second transmission rod (426) by its own elasticity; and / or, The locking structure of the second piston (432) is a flared groove (441), and the second transmission rod (426) is formed with an annular groove (442) on the shaft section extending into the flared groove (441), and a plurality of balls (443) are arranged in the annular groove (442). The axial movement of the second piston (432) causes the side wall of the flared groove (441) to press or loosen the balls (443) in the annular groove (442), thereby achieving locking or unlocking.

11. The electrode conversion device according to claim 10, characterized in that: The first linear actuator (42) and the second linear actuator (43) are hydraulic cylinders, pneumatic cylinders or linear motors (31); and / or, The first linear actuator (42) and the second linear actuator (43) are single-acting cylinders, and the electrode conversion device is equipped with an air source and a rotary air distribution structure, and the air source supplies air to the first linear actuator (42) and the second linear actuator (43) through the rotary air distribution structure; The rotary air distribution structure comprises a first air supply pipeline (61), a second air supply pipeline (62) and a pneumatic control pipeline (63) located in the hollow main shaft (41); The first air supply pipeline (61) is connected to a cavity of the slide cylinder (421) of the first linear actuator (42) away from the rotating member (1), and is used to extend the rotating member (1) when air is supplied; The second air supply pipeline (62) is connected to a cavity of the cylinder body (431) of the second linear actuator (43) close to the rotating member (1), and is used to unlock the rotating member (1) when air is supplied; The pneumatic control pipeline (63) is connected to the cavity of the cylinder (431) of the second linear actuator (43) away from the rotating member (1), and is used to set a logic valve to realize the sequential action logic control of the first linear actuator (42) and the second linear actuator (43).

12. The electrode conversion device according to claim 11, characterized in that: The first air supply pipeline (61) is provided with a first reversing valve (71), and the first reversing valve (71) has an exhaust port for relieving pressure; The second air supply pipeline (62) is provided with a second reversing valve (72), and the second reversing valve (72) has an exhaust port for relieving pressure; The logic valve comprises a dual-pressure valve (73) and a shuttle valve (74), which are used to control the first linear actuator (42) and the second linear actuator (43) to realize the action sequence of "the second linear actuator (43) is unlocked → the first linear actuator (42) is extended → the rotating member (1) is rotated → the first linear actuator (42) is retracted → the second linear actuator (43) is locked".

13. The electrode conversion device according to claim 6, characterized in that: The electrode arm assembly (2) comprises an electrode (21) and an electrode support (22), wherein the electrode support (22) is L-shaped or extends outwardly, so that the electrode (21) is located outside the axial projection of the rotating member (1); and / or, The connection of the electrode arm assembly (2) on the rotating member (1) is a detachable connection or a position-adjustable connection; and / or, The number of the electrode arm assemblies (2) is set to 2-10, and they are evenly or unevenly arranged on the rotating member (1); and / or, The electrode shape of each electrode arm assembly (2) matches nuts of different specifications; and / or, The supporting shell further comprises a fixed rear seat (56), wherein the hollow main shaft (41) is arranged in the rear seat (56); and / or, The rotary drive source (3) further comprises a reducer (32), wherein the reducer (32) is at least one of a planetary gear reducer, a cycloid pinwheel reducer, an RV reducer, a conical friction transmission reducer and a worm reducer; and / or, The rotation driving source (3) is a pneumatic rotary motor, a hydraulic rotary motor or an electric motor (31).

14. A nut projection welding machine, comprising an electrode conversion device as claimed in any one of claims 1 to 13.

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