CN110405306A - Pressure-applying mechanism, stringer and pressure-applying method - Google Patents

Abstract

This application discloses a kind of pressure exerting arrangement, string welding machine and pressure methods, the pressure exerting arrangement includes driving portion, driving section and pressure unit, the driving end of driving portion is connected by the first end of pin shaft and driving section, driving section is mounted in shaft, and the second end of driving section is connected by the first end of installation axle and pressure unit；The first end of the driving end pushing tow driving section of driving portion, so that driving section is rotated around shaft, the second end of driving section pushes the first end of pressure unit, so that pressure unit presses to the object that is pressed being located at the second end position of pressure unit.The application is when the driving end of driving portion drives, the first end of pushing tow driving section, rotate driving section around shaft, the second end of driving section pushes the first end of pressure unit during rotation, and then pressure unit is made to be pressed object pressure to the second end of pressure unit, it realizes and is pressed object because of the effect of pressure deformation.

Description

Pressure-applying mechanism, stringer and pressure-applying method

technical field

The invention belongs to the technical field of battery component production, and relates to a pressure applying mechanism, a string welding machine and a pressure applying method.

Background technique

In the production process of battery components, there is a step of connecting battery sheets in series by using ribbons. Two adjacent cells are connected together by a set of ribbons. The first part of the ribbon is welded to the front busbar of the previous cell, and the second part of the ribbon is welded to the busbar on the back of the next cell. .

At present, there is a production method that stacks two connected cells. Since the ribbons have a certain thickness, the cells are also thin and brittle. When lamination is processed into a battery panel assembly, damage is prone to occur between two adjacent battery sheets.

Therefore, it is necessary to add a process of flattening and deforming the welding ribbon and the corresponding structure in the equipment for battery string production, so as to flatten and deform the middle part of the welding ribbon used to connect two adjacent battery pieces in series, and then adapt to the battery. Lamination requirements.

Contents of the invention

The invention provides a pressure-applying mechanism, a stringer and a pressure-applying method. The technical solution is as follows:

In the first aspect, the present application provides a pressure applying mechanism, which includes a driving part, a transmission part and a pressure applying part, the driving end of the driving part is connected to the first end of the transmission part through a pin shaft, and the transmission part is installed on On the rotating shaft, the second end of the transmission part is connected to the first end of the pressing part through the installation shaft; the driving end of the driving part pushes the first end of the transmission part to make the transmission part rotate around the rotating shaft, and the second The end pushes the first end of the pressing part, so that the pressing part presses the pressed object located at the second end of the pressing part.

By connecting the driving end of the driving part with the first end of the transmission part, the transmission part is installed on the rotating shaft, the second end of the transmission part is connected with the first end of the pressing part through the installation shaft, and the driving end of the driving part When driving, push the first end of the transmission part to make the transmission part rotate around the rotating shaft, and the second end of the transmission part pushes the first end of the pressure application part during the rotation process, so that the pressure application part moves toward the pressure application part. The object to be pressed at the second end exerts pressure to realize the effect that the object to be pressed is deformed due to pressure.

Optionally, the pressing mechanism provided by the present application further includes a supporting seat, and the pressing part is located in the guide groove of the supporting seat.

By arranging the support seat with the guide groove, the pressure exerting part is arranged in the guide groove, and the guide groove can guide the pressure exerting part in the process of realizing the pressure exerting action, so as to ensure the precise pressure exerted on the object to be pressed.

Optionally, the first end of the transmission part or the driving end of the driving part is provided with a first waist-shaped hole, the pin shaft is accommodated in the first waist-shaped hole, and the driving end of the driving part is connected to the first waist-shaped hole through the pin shaft and the first waist-shaped hole. The first end of the transmission part is connected.

By setting the first waist-shaped hole for receiving the pin on the first end of the transmission part or the driving end of the driving part, when the driving end of the driving part drives the first end of the transmission part, the transmission part can The stroke of rotating around the rotating shaft realizes the rotation of the transmission part.

Optionally, the first end of the pressing part or the second end of the transmission part is provided with a second waist-shaped hole, the installation shaft is accommodated in the second waist-shaped hole, and the second end of the transmission part passes through the installation shaft and the second waist. The type hole is connected with the first end of the pressing part.

By setting the second waist-shaped hole for receiving the installation shaft on the first end of the pressing part or the second end of the transmission part, when the driving end of the driving part drives the first end of the transmission part, the transmission part There is a stroke that can rotate around the rotating shaft to realize the rotation of the transmission part.

Optionally, the pressure applying mechanism provided in the present application further includes a base, which is used to bear the object to be pressed.

Optionally, the pressed object is an elongated object, and the base is provided with a groove for accommodating the elongated object.

By providing a base with a groove for accommodating the object to be pressed to fix the object to be pressed, the pressing effect is ensured.

Optionally, the groove includes a pressure application area and a non-pressure application area, the pressure application area is opposite to the second end of the pressure application part, and the height of the pressure application area is higher than that of the non-pressure application area.

By setting the height of the groove to be different, a bending effect can be produced when pressing the pressed object.

Optionally, the pressurized area transitions to the non-pressurized area through the downslope.

By transitioning the pressure-applying area and the non-pressure-applying area through the downhill surface, the bending effect of the object to be pressed can be met when it is pressed to form a bend, and the bending effect of the object to be pressed can be reduced after being pressed and bent. probability of being damaged.

Optionally, the side of the second end of the pressing part away from the downhill surface is recessed inwardly.

By arranging the second end of the pressing part as an inner recess, when the object to be pressed is bent by pressure, the part opposite to the second end of the pressing part can be tilted to meet the bending of the object to be pressed. Require.

Optionally, the pressed object is a welding ribbon.

In the second aspect, the present application also provides a stringer, the stringer includes the pressing mechanism provided in the first aspect and various optional modes of the first aspect, the stringer also includes a ribbon supply Mechanism, cell feeding mechanism, welding mechanism, wherein: the ribbon feeding mechanism provides the ribbon to the second end position of the pressure applying part of the pressure applying mechanism, and the pressure applying mechanism applies pressure to deform the ribbon, and the battery sheet supply The material mechanism and the ribbon feeding mechanism work together to stack the battery slices and the pressed ribbons, and the welding mechanism heats the stacked ribbons and battery slices to weld the ribbons to the corresponding batteries on-chip to form battery strings.

By setting the pressure applying mechanism, the deformation of the welding ribbon can be realized, and through the cooperation of the welding ribbon feeding mechanism and the cell feeding mechanism, the sequential stacking of the deformed welding ribbon and the battery sheet can be realized, and the welding mechanism can be used to realize the The deformed ribbon is welded to the battery sheet to complete the welding of the battery string, which can reduce the probability of damage when the battery sheet is stacked while achieving the effect of lamination between adjacent battery sheets.

In a third aspect, the present application also provides a method for applying pressure, which includes:

The controller controls the driving end of the driving part to perform a driving action at the first predetermined timing according to the way the ribbon is connected to the battery sheet;

The driving end of the driving part drives the first end of the pushing transmission part, the transmission part rotates around the rotating shaft, the second end of the transmission part pushes the first end of the pressing part, and the pressing part is located at the second end of the pressing part. The welding ribbon at the place is put under pressure;

The controller controls the driving end of the driving part to reset at the second predetermined timing, and the driving end drives the transmission part to reset, and the transmission part drives the pressing part to retreat to complete a pressure shaping of the welding strip.

The drive and reset of the driving part is controlled by the controller. When the driving end of the driving part is driven, the transmission part is driven, and the transmission part is used to apply force to the pressing part, thereby completing the pressing of the object to be pressed and realizing the pressure The effect of deforming an object due to pressure.

It is to be understood that both the foregoing general description and the following detailed description are exemplary only and are not restrictive of the invention.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

Fig. 1 is a structural schematic diagram of a pressure applying mechanism provided by an embodiment of the present application;

Fig. 2 is a schematic cross-sectional view of a pressure applying mechanism provided by an embodiment of the present application;

Fig. 3 is a schematic diagram of a base provided by an embodiment of the present application.

Wherein, the reference signs are as follows:

10, driving part; 11, driving end; 20, transmission part; 21, first end of transmission part; 211, first waist hole; 22, rotating shaft; 23, second end of transmission part; 231, second waist Type hole; 30, pressure application part; 31, the first end of pressure application part; 41, pin shaft; 42, installation shaft; 50, pressed object; 60, support seat; 70, base; 71, groove ; 711 , the pressurized area; 712 , the non-pressurized area.

Detailed ways

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention as recited in the appended claims.

In the production of battery components, in order to increase the production capacity of the battery per unit area, it is usually used to reduce the coverage area of the front side of the battery or to reduce the gap between the batteries. For the battery assembly formed by connecting the battery slices with a ribbon, since the ribbon has a certain thickness, and the battery slice is relatively thin and fragile, when the ribbon connects two battery slices, there will be a certain gap between the two battery slices. This will reduce the production capacity of the cells per unit area. Therefore, in order to solve this problem, two adjacent cells can be stacked, but the welding strips between the stacked parts need to be crushed and deformed. Aiming at the flattening and deformation of the welding strip, the present application provides a pressing mechanism, the specific structure of which can be seen in Fig. 1-Fig. 3 .

Fig. 1 is a structural schematic diagram of a pressure applying mechanism provided by an embodiment of the present application. The pressure applying mechanism provided by the present application includes a driving part 10, a transmission part 20 and a pressing part 30, and the driving end 11 of the driving part 10 connects with the pin shaft 41 The first end 21 of the transmission part is connected by transmission, the transmission part 20 is installed on the rotating shaft 22, the second end 23 of the transmission part is connected with the first end 31 of the pressing part through the installation shaft 42; the driving end 11 of the driving part 10 pushes The first end 21 of the transmission part, so that the transmission part 20 rotates around the rotating shaft 22, and the second end 23 of the transmission part pushes the first end 31 of the pressing part, so that the pressing part 30 moves toward the first end 31 of the pressing part. The pressurized objects 50 at the two end positions pressurize.

In a possible implementation manner, the position where the transmission part 20 is installed on the rotating shaft 22 may be close to the second end 23 of the transmission part, or close to the first end 21 of the transmission part, or located in the middle of the transmission part 20 .

Optionally, the positions of the first end 21 of the transmission part and the second end 23 of the transmission part relative to the installation shaft 22 may form bends in the same direction. For example, the transmission part 20 may be a U-shaped structure or a structure similar to a U-shaped structure.

The driving unit 10 mentioned here can be a driving mechanism such as an air cylinder or an electric cylinder. The driving end 11 of the driving part 10 can be a component driven by the driver of the driving part 10. Taking the driving part 10 as an example of an air cylinder, the driving end 11 of the driving part 10 can be understood as a telescopic rod of the air cylinder.

In practical applications, in order to connect the driving end 11 of the driving part 10 with the first end 21 of the transmission part through the pin shaft 41, some structures can be made on the driving end 11 of the driving part 10 or the first end 21 of the transmission part. Designed to facilitate the installation of the pin shaft 41.

In a possible implementation, in order to enable the transmission part 20 to rotate around the rotating shaft 22 driven by the driving part 10, a first waist-shaped hole 211 may also be provided at the first end 21 of the transmission part, as shown in FIG. As shown, the pin shaft 41 is accommodated in the first waist-shaped hole 211 , and the driving end 11 of the driving part 10 is connected to the first end 21 of the transmission part through the pin shaft 41 and the first waist-shaped hole 211 . Apparently, a first waist-shaped hole can also be provided on the driving end 11 of the driving part 10 , so that the first end 21 of the transmission part is connected to the driving end 11 of the driving part 10 through the pin shaft 41 and the first waist-shaped hole.

In this way, by setting the first waist-shaped hole 211 for accommodating the pin shaft 41 at the first end 21 of the transmission part, the drive end 11 of the drive part 10 can make the transmission part 20 when driving the first end 21 of the transmission part. There is a stroke that can rotate around the rotating shaft 22 to realize the rotation of the transmission part 20 .

In order to connect the second end 23 of the transmission part with the first end 31 of the pressing part through the installation shaft 42, some structural designs can be carried out on the second end 23 of the transmission part or the first end 31 of the pressing part so as to facilitate Install the above-mentioned installation shaft 42 .

In a possible implementation, in order to enable the transmission part 20 to rotate around the rotating shaft 22 driven by the driving part 10, a second waist-shaped hole 231 may also be provided at the second end 23 of the transmission part, as shown in FIG. As shown, the installation shaft 42 is accommodated in the second waist-shaped hole 231 , and the second end 23 of the transmission part is connected to the first end 31 of the pressing part through the installation shaft 42 and the second waist-shaped hole 231 . Apparently, a second waist-shaped hole can also be provided on the first end 31 of the pressing part, so that the second end 23 of the transmission part passes through the installation shaft 42 and the second waist-shaped hole 231 and the first end 31 of the pressing part. connect.

In this way, by setting the second waist-shaped hole 231 for accommodating the mounting shaft 42 at the second end 23 of the transmission part, the driving end 11 of the driving part 10 can make the transmission part 20 when driving the first end 21 of the transmission part. There is a stroke that can rotate around the rotating shaft 22 to realize the rotation of the transmission part 20 .

Generally speaking, in order to ensure that the pressing direction of the pressing part 30 is accurate, the pressing mechanism provided in the present application may further include a support seat 60 , and the pressing part 30 is located in a guide groove of the support seat 60 . By setting the support seat 60 with a guide groove, the pressure exerting part 30 is arranged in the guide groove, and the guide groove can guide the pressure exerting part 30 in the process of realizing the pressure applying action, so as to ensure precise pressure on the pressed object 50 .

The pressing mechanism provided by the present application may also include a base 70, as shown in FIG. 3 , which is a schematic diagram of a base provided by an embodiment of the present application. The pressing object 50 is a strip-shaped object, such as a welding ribbon, a bus bar, etc., and a groove 71 for accommodating the strip-shaped object is provided on the base 70 .

The pressing mechanism provided in the present application is provided with a base 70 having a groove 71 for accommodating the object 50 to be pressed, so as to fix the object to be pressed, so as to ensure the pressing effect.

Optionally, the groove 71 may include a pressing area 711 and a non-pressing area 712 , the pressing area 711 is opposite to the second end of the pressing portion 30 , and the height of the pressing area 711 is higher than that of the non-pressing area 712 . Further, in order to realize the pressure exerted by the second end of the pressing part 30 on the pressed object 50 in the groove 71, the shape of the pressing area 711 in the groove 71 usually matches the shape of the second end of the pressing part 30, so as to accommodate the second end of the pressing part.

In this way, by setting the height of the groove 71 to be different, a bending effect can be generated when pressing the object 50 to be pressed.

Further, the pressurized area 711 transitions to the non-pressurized area 712 through a downward slope. By transitioning the pressing area 711 and the non-pressing area 712 through a downward slope, it is possible to make the pressed object 50 meet the desired bending effect when it is pressed to form a bend, and reduce the pressure on the pressed object 50. The probability of being damaged after bending.

In practical applications, according to the pressure deformation requirements of the object 50 to be pressed, the side of the second end of the pressure applying portion away from the downhill surface can be recessed inward, as shown in FIG. 2 . By arranging the second end of the pressing part to be inwardly recessed, when the pressed object 50 is pressed and bent, the part opposite to the second end of the pressing part can be tilted to meet the requirements of the pressed object. 50 bending requirements.

Optionally, both ends of the groove 71 may be designed to open outwards, as shown in FIG. 3 , to facilitate the introduction and export of the pressed object 50 .

To sum up, the pressure applying mechanism provided by the present application connects the driving end of the driving part with the first end of the transmission part, the transmission part is installed on the rotating shaft, and the second end of the transmission part passes through the installation shaft and the pressure application mechanism. When the driving end of the driving part is driven, the first end of the transmission part is pushed to make the transmission part rotate around the rotating shaft, and the second end of the transmission part pushes the first end of the pressing part during the rotation. One end, and then make the pressure exerting part exert pressure on the object to be pressed at the second end of the pressure exerting part, so as to achieve the effect that the object to be pressed is deformed due to the pressure.

The present application also provides a stringer. The stringer includes a pressure applying mechanism. The stringer may also include a ribbon feeding mechanism, a cell feeding mechanism, and a welding mechanism. Wherein, the pressure applying mechanism is the pressure applying mechanism shown in Fig. 1-Fig. 3, for details, please refer to the description of Fig. 1-Fig.

Here, the ribbon feeding mechanism can be used to supply the ribbon to the second end of the pressing part of the pressing mechanism. Usually, the ribbon provided by the ribbon feeding mechanism can be a flat ribbon or a cylindrical ribbon. Generally, the ribbon feeding mechanism may include a ribbon reel, a ribbon pulling device, a cutter, a ribbon feeding device, etc., a ribbon is installed on the ribbon reel, and the ribbon pulling device pulls the welding ribbon from the ribbon reel. Ribbon, the cutter set at the predetermined position cuts the ribbon drawn by the ribbon pulling device to form a ribbon of predetermined length, and the ribbon feeding device feeds the cut ribbon to the pressure of the pressure mechanism at the second end position of the section.

The pressing mechanism applies pressure to deform the welding ribbon provided by the welding ribbon feeding mechanism.

The cell feeding mechanism and the ribbon feeding mechanism work together to stack the cells and the ribbons after pressure. The stacking process here is carried out according to the order of the cells and ribbons required for the battery string welding overlay processing. The cell feeding mechanism may include a magazine and a battery feeding device, the magazine is used to carry the battery, the battery feeding device sucks the battery from the magazine, and feeds the battery to the conveying device. In practical application, the cell sheet feeding mechanism and the ribbon feeding mechanism cooperate together to stack the cell sheet and the solder ribbon after pressure is applied to the conveying device.

The welding mechanism heats the stacked ribbons and battery sheets to weld the ribbons to the corresponding battery sheets to form a battery string. The heating here can be infrared heating.

To sum up, the stringer provided by this application realizes the pressure deformation of the ribbon by setting the pressure applying mechanism, and realizes the deformation of the ribbon and the welded ribbon through the cooperation of the ribbon feeding mechanism and the cell feeding mechanism. The cells are stacked in order, and the deformed ribbon is welded to the cells through the welding mechanism, and then the welding of the battery strings is completed. While the effect of stacking adjacent cells can be achieved, the stacking of cells is reduced. Probability of chip damage.

When using the pressure applying mechanism provided by the application to apply pressure to the welding strip, the application also provides a method for applying pressure, which can be applied to the pressure applying mechanism shown in Figures 1-3, or by The pressing mechanism shown in Fig. 1-Fig. 3 is implemented. The method of applying pressure may include the steps of:

S1. The controller controls the driving end of the driving part to perform a driving action at the first predetermined timing according to the way the ribbon is connected to the battery sheet;

In practical applications, in order to realize the control of the driving timing of the driving end of the driving part, the pressure applying mechanism may include a controller, or be electrically connected with the controller, or connected with the controller in communication, and the controller is preset with a code to control The processing module of the controller executes these codes to control the driving timing of the driving part.

When the controller controls the driving end of the driving part to extend out at the first predetermined timing according to the way the ribbon is connected to the battery slice, the driving end of the driving part drives the first end of the transmission part, that is, step S2 is executed.

S2. The driving end of the driving part drives the first end of the pushing transmission part, the transmission part rotates around the shaft, the second end of the transmission part pushes the first end of the pressing part, and the pressing part moves toward the second end of the pressing part Pressure is applied to the ribbon at the end position;

S3. The controller controls the driving end of the driving part to reset at the second predetermined timing, and the driving end drives the transmission part to reset, and the pressing part retreats to complete a pressure shaping on the welding strip.

When the controller controls the driving end of the driving part to retract at the second predetermined timing according to the way the welding ribbon is connected to the battery, the driving end of the driving part resets, and the driving end drives the transmission part to reset, and the pressing part retreats to complete the bonding of the welding ribbon. A pressure shaping. Then continue to perform the step of applying pressure to the next pressure application position of the welding ribbon or the next pressure application position of the welding ribbon, so as to realize the function of automatically applying pressure and deforming the continuous feeding of multiple welding ribbons.

Obviously, in practical applications, the pressure applying mechanism can also apply pressure to deform different positions of the same welding ribbon, and only need to press one position of the welding ribbon to drive the welding ribbon to move, so that the next welding ribbon needs to be applied. The pressing part may be the second end of the pressing part, so that the second end of the pressing part can press and deform the next part of the welding ribbon that needs to be used.

In summary, the pressure application method provided by this application controls the driving and reset of the driving part through the controller, and when the driving end of the driving part is driven, the transmission part is driven to apply force to the pressure application part by the transmission part, and then completes Apply pressure to the object to be pressed to achieve the effect that the object to be pressed is deformed by the pressure.

Other embodiments of the invention will be readily apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present invention. These modifications, uses or adaptations follow the general principles of the present invention and include common knowledge or conventional technical means in the technical field not described in the present invention . The specification and examples are to be considered exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It should be understood that the present invention is not limited to the precise constructions which have been described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims (10)

1. A pressure applying mechanism, characterized in that, the pressure applying mechanism comprises a driving part, a transmission part and a pressure applying part, and the driving end of the driving part is connected with the first end of the transmission part through a pin shaft, so The transmission part is installed on the rotating shaft, and the second end of the transmission part is connected with the first end of the pressure applying part through the installation shaft; The driving end of the driving part pushes the first end of the transmission part to make the transmission part rotate around the shaft, and the second end of the transmission part pushes the first end of the pressing part , so that the pressing part presses the object to be pressed at the second end of the pressing part. 2 . The pressure applying mechanism according to claim 1 , further comprising a support seat, and the pressure applying part is located in a guide groove of the support seat. 3 . 3. The pressing mechanism according to claim 1, wherein the first end of the transmission part or the driving end of the driving part is provided with a first waist-shaped hole, and the pin is accommodated in the first In a waist-shaped hole, the driving end of the driving part is connected to the first end of the transmission part through the pin shaft and the first waist-shaped hole. 4. The pressing mechanism according to claim 1, characterized in that, the first end of the pressing part or the second end of the transmission part is provided with a second waist-shaped hole, and the installation shaft is accommodated in the In the second waist-shaped hole, the second end of the transmission part is connected to the first end of the pressing part through the installation shaft and the second waist-shaped hole. 5 . The pressure applying mechanism according to claim 1 , further comprising a base for carrying the object to be pressed. 6 . 6. The pressing mechanism according to claim 5, wherein the object to be pressed is a strip-shaped object, and the base is provided with a groove for accommodating the strip-shaped object, and the The groove includes a pressure application area and a non-pressure application area, the pressure application area is opposite to the second end of the pressure application part, and the height of the pressure application area is higher than the non-pressure application area. 7. The pressure applying mechanism according to claim 6, characterized in that, the pressure application area transitions to the non-pressure application area through a downslope; the second end of the pressure application part is far away from the side of the downslope One side is sunken inwardly. 8. The pressing mechanism according to claim 1, wherein the object to be pressed is a welding ribbon. 9. A stringer, characterized in that, the stringer includes the pressure applying mechanism as claimed in any one of claims 1-8, and the stringer also includes a ribbon feeding mechanism, a cell supply A material mechanism and a welding mechanism, wherein: the welding ribbon feeding mechanism provides the welding ribbon to the second end position of the pressure applying part of the pressure applying mechanism, and the pressure applying mechanism applies pressure to deform the welding ribbon, The cell sheet feeding mechanism and the ribbon feeding mechanism cooperate together to stack the cell sheets and the pressed ribbons, and the welding mechanism heats the stacked ribbons and the cell sheets, A battery string is formed by welding the ribbon to the corresponding battery sheet. 10. A method of applying pressure, characterized in that, the method of applying pressure comprises: The controller controls the driving end of the driving part to perform a driving action at the first predetermined timing according to the way the ribbon is connected to the battery sheet; The driving end of the driving part drives the first end of the pushing transmission part, the transmission part rotates around the shaft, the second end of the transmission part pushes the first end of the pressing part, and the pressing part The welding ribbon located at the second end of the pressure applying part applies pressure; The controller controls the driving end of the driving part to reset at the second predetermined timing, the driving end drives the transmission part to reset, and the transmission part drives the pressure applying part to retreat to complete one application of the welding ribbon. Pressure shaping.