CN210100736U

CN210100736U - Ultrasonic welding device

Info

Publication number: CN210100736U
Application number: CN201920795106.3U
Authority: CN
Inventors: 龚志龙; 李大柱
Original assignee: Huangshan Futian Precision Manufacturing Co Ltd
Current assignee: Huangshan Futian Precision Manufacturing Co Ltd
Priority date: 2019-05-30
Filing date: 2019-05-30
Publication date: 2020-02-21
Anticipated expiration: 2029-05-30

Abstract

The utility model discloses an ultrasonic welding device, which is provided with an ultrasonic welding head and an anvil roller matched with the ultrasonic welding head, wherein the anvil roller is provided with a rotating center, and the ultrasonic welding head is provided with an end surface giving welding energy to materials; the ultrasonic welding head further comprises a first structure intersection line passing through the rotation center and perpendicular to the end face of the ultrasonic welding head, and a second structure intersection line located in the middle of the end face of the ultrasonic welding head and perpendicular to the end face of the ultrasonic welding head, wherein the first structure intersection line and the second structure intersection line are parallel to each other, and the first structure intersection line is offset towards the downstream side relative to the second structure intersection line. The utility model discloses do the appropriate skew with anvil roll position for ultrasonic bonding tool central line to make the material when the clearance between ultrasonic bonding tool and anvil roll, have great initial compression clearance in the entrance, effectively prevented the risk of cuting of material in welding process, help improving welding strength simultaneously, the outage rate of reduction equipment.

Description

Ultrasonic welding device

Technical Field

The utility model relates to a disposable hygienic articles equips the manufacture field, especially relates to an ultrasonic welding device that prevents that material from being truncated.

Background

Conventionally, as a disposable sanitary product, for example, a disposable sanitary product having a front abdominal portion, a back portion, and a crotch portion, and in which the front abdominal portion and the back portion are ultrasonically welded by a pair of side seal portions (or weld portions) is known. In forming the side seal, a method is employed in which a thermoplastic sheet material constituting the front abdominal section and the back section is continuously supplied to an anvil roller rotatable about a predetermined axis and is disposed between ultrasonic horns opposed to the outer peripheral surface of the anvil roller in cooperation with the anvil. The thermoplastic sheets are supplied between the anvil roller and the ultrasonic horn in a state of facing each other, and the thermoplastic sheets continuously supplied between the anvil roller and the ultrasonic horn are subjected to ultrasonic welding intermittently at a period in which the anvil roller approaches the ultrasonic horn. Thus, a welded portion is formed in which the thermoplastic sheets facing each other are welded to each other.

Since the conventional ultrasonic horn is arranged concentrically with the anvil roll, specifically, if a perpendicular line L1 is made from the center O1 of rotation of the anvil roll to the end face of the ultrasonic horn, the perpendicular line L1 coincides with the center line L2 of the end face of the ultrasonic horn, since the gap B1 between the material entering the ultrasonic horn and the anvil roll is small (as shown in fig. 9), the risk of the material being cut off during the welding process is greatly increased, and the equipment downtime is increased.

Meanwhile, the problem of product code changing is often involved in the production process, and the common method is as follows: the diameter of a welding mechanism of the welding device is changed to increase or decrease the arc length of the circumference, so that the purpose of changing the size is achieved, and therefore the whole welding mechanism needs to be changed for the welding device, namely, the welding device is provided with various types of welding mechanisms corresponding to products with different sizes, so that the traditional device has the defects of high manufacturing cost, long consumed time, influence on-site production efficiency and the like.

In addition, in the conventional ultrasonic welding device, since no material clamping mechanism is arranged before and after the welding station, when the ultrasonic welding head works, the ultrasonic energy load applied to the anvil roller is large, the welded material is easy to shake, the precision of the welding position is reduced, and the quality of the welding part is reduced.

SUMMERY OF THE UTILITY MODEL

In order to overcome the problems, the utility model provides an ultrasonic welding device, the material of solving the traditional device existence easily blocks, leads to the higher problem of equipment outage rate.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: an ultrasonic welding device for intermittently welding a plurality of pre-welding areas arranged at equal intervals on a sheet material strip, which comprises an ultrasonic horn and an anvil roller matched with the ultrasonic horn, wherein the sheet material strip is continuously conveyed to a gap between the ultrasonic horn and the anvil roller from an upstream side to a downstream side to be welded with each other, the anvil roller has a rotation center, and the ultrasonic horn has an end face for giving welding energy to materials; the ultrasonic welding head further comprises a first structure intersection line passing through the rotation center and perpendicular to the end face of the ultrasonic welding head, and a second structure intersection line located in the middle of the end face of the ultrasonic welding head and perpendicular to the end face of the ultrasonic welding head, wherein the first structure intersection line and the second structure intersection line are parallel to each other, and the first structure intersection line is offset towards the downstream side relative to the second structure intersection line. Adopt as above technical scheme, through with first structure intersecting line for second structure intersecting line towards the offset setting of low reaches side direction, increased the initial compression clearance when welding material gets into the welding area, effectively prevented the risk of cutting of material in welding process, help improving welding strength simultaneously, reduce the outage rate of equipment.

Further, the first configuration intersection line has an offset characteristic relative to the second configuration intersection line, the offset direction is the traveling direction of the sheet material strip, and the offset distance is 2-5 mm. In addition, the anvil roll has a slight gap to the end face of the ultrasonic horn, the gap being 0.01 to 0.1 mm.

In order to solve the problems of high code changing cost, time and labor waste of the traditional device, N pattern parts are correspondingly arranged on the anvil roll, the pattern parts are matched with an ultrasonic welding head to weld the pre-welding areas of the sheet strips, and the device also comprises a servo driving mechanism for driving the anvil roll to rotate at a constant speed or at a periodic variable speed; when the pattern on the anvil roll passes through the end face of the ultrasonic welding head, the linear speed of the surface of the anvil roll is equal to the linear speed of the sheet material strip under the action of the servo driving mechanism. By adopting the technical scheme, when the product is changed, the ultrasonic welding of a plurality of product sizes can be realized by adopting one anvil roller through the periodical speed change design of the servo driving mechanism, so that the manufacturing cost and the labor intensity of workers are greatly reduced. N may be any integer of 1, 2, or 3 … ….

Furthermore, the servo driving mechanism comprises a servo motor, a speed reducer and a coupler, and the servo motor is connected with the anvil roller through the speed reducer and the coupler, so that the anvil roller performs constant-speed or periodic variable-speed rotary motion.

Further, when the anvil roll rotates at a periodic variable speed, the anvil roll performs N variable speed cycles each time the anvil roll rotates one circle, each variable speed cycle includes a constant speed interval and a variable speed interval, and the angle of the constant speed interval is 20 to 50 degrees. Furthermore, an angle bisector of the uniform speed interval coincides with the intersection line of the first structure.

Further, the anvil roll rotates one round with a circumference of S0 and the interval between adjacent pre-welding areas is S1; when S0/N is equal to S1, the anvil roller rotates at a constant speed, and when S0/N is not equal to S1, the anvil roller rotates at a periodically variable speed. Specifically, when S0/N > S1, the anvil roll performs N speed change cycles per rotation of the anvil roll, each speed change cycle comprises a low speed uniform section and a speed change section, the pattern part passes through the end face of the ultrasonic welding head in the low speed uniform section in the speed change cycle, the angle g1 of the low speed uniform section is 20-50 degrees, and the angle of the speed change section is 360 degrees/N-g 1. When S0/N < S1, the anvil roll performs N variable speed cycles every time the anvil roll rotates, each variable speed cycle comprises a high-speed constant speed section and a variable speed section, the pattern part passes through the end face of the ultrasonic welding head in the high-speed constant speed section in the variable speed cycle, the angle g1 of the high-speed constant speed section is 20-50 degrees, and the angle of the variable speed section is 360 degrees/N-g 1.

Further, the anvil roll rotates a number of speed variation cycles equal to the number of pattern portions on the anvil roll. The product formed by welding is a disposable sanitary product, such as baby pull-ups, adult pull-ups, female menstrual pants, and the like.

In order to solve the problems of easy material shaking, low welding position precision and low quality of the traditional device, the ultrasonic welding device is provided with a welding station consisting of the ultrasonic welding head and an anvil roller and a clamping station for holding the sheet material strip. The clamping stations are respectively arranged at the upstream side and the downstream side of the welding station and are provided with belt pressure feeding mechanisms for ensuring the flatness and the tension of the sheet material strips.

Furthermore, the belt pressure feeding mechanism comprises an upper pressure belt and a lower pressure belt, the rotation of the upper pressure belt and the rotation of the lower pressure belt are both driven by power, and the surface linear velocities of the upper pressure belt and the lower pressure belt are the same. For the same group of belt pressing and conveying mechanisms, the upper pressing belt and the lower pressing belt can be respectively connected with the driving motor, and the linear velocities of the surfaces of the upper pressing belt and the lower pressing belt are ensured to be consistent by controlling the rotating speed of the driving motor; the upper pressing belt and the lower pressing belt can be connected with a synchronizing mechanism, and the purpose is achieved through one motor.

In order to prevent more effectively that product shake and fold problem from giving the harmful effects that ultrasonic bonding brought, go up and press the belt down and preferably adopt the sponge belt, so can the tension of absorbent material, when guaranteeing the welding effect, promote the outward appearance nature of product. Furthermore, the upper pressing belt can move up and down in a vertical plane relative to the lower pressing belt, and exerts pressure on the lower pressing belt during operation, and the pressure is adjustable. Through pressing the belt for pressing the belt down in vertical plane up-and-down motion on, and then can look at concrete operating mode and carry out corresponding adjustment to this pressure value.

As a further preference of the present invention, the belt pressure feed mechanism is provided with two sets, which include a first belt pressure feed mechanism located on the upstream side of the welding station and a second belt pressure feed mechanism located on the downstream side of the welding station. The belt surface line speed of the second belt pressing and conveying mechanism is greater than or equal to the belt surface line speed of the first belt pressing and conveying mechanism.

The utility model has the advantages that:

1. the utility model discloses do the appropriate skew with anvil roll position for ultrasonic bonding tool central line to make the material when the clearance between ultrasonic bonding tool and anvil roll, have great initial compression clearance in the entrance, effectively prevented the risk of cuting of material in welding process, help improving welding strength simultaneously, the outage rate of reduction equipment.

2. The utility model discloses a servo actuating mechanism changes the rotation rate of hammering block roller, and then realizes the production speed that can match different size products according to the hammering block roller of certain diameter design, adapts to the welding production of many size products, has greatly reduced workman's intensity of labour, has reduced the manufacturing cost of device.

3. The utility model discloses can guarantee that the product has good roughness and tension characteristic when passing through the ultrasonic bonding station to make the slice thing strip more be favorable to implementing ultrasonic bonding, when guaranteeing the welding effect, promote the pleasing to the eye degree of product, prevent the product shake and the harmful effects that the fold problem brought for ultrasonic bonding.

Drawings

Fig. 1 is a schematic view of the present invention.

Fig. 2 is a schematic diagram of the present invention.

Fig. 3 is a schematic structural diagram of the present invention.

Fig. 4 is a partial enlarged view of the present invention, illustrating the offset of the first structural intersection relative to the second structural intersection.

Fig. 5 is a graph of angular displacement versus time for the anvil roll of example 1.

Fig. 6 is a graph of angular velocity versus time for the anvil roll of example 1.

Fig. 7 is a graph of angular displacement versus time for an anvil roll according to example 2.

Fig. 8 is a graph of angular velocity versus time for an anvil roll of example 2.

Fig. 9 is a schematic view of the material entering between the ultrasonic horn and the anvil roll in the conventional apparatus.

Figure 10 is a schematic view of the modified material of the present invention entering between the ultrasonic horn and the anvil roll.

Detailed Description

The present invention will be described below with reference to the drawings of embodiments of the present invention.

As shown in fig. 1 to 2, an ultrasonic welding apparatus for intermittently welding a plurality of pre-welding regions 102 arranged at equal intervals on a plurality of sheet material strips 101 includes an ultrasonic horn 1 and an anvil roll 2 fitted thereto, the anvil roll 2 being provided with N patterns 3, and the sheet material strips 101 being continuously conveyed from an upstream side MD1 toward a downstream side MD2 to a gap between the ultrasonic horn 1 and the patterns 3 of the anvil roll 2 to be welded to each other. The arrows in fig. 1 illustrate the direction of travel of the material.

The anvil roll 2 is also provided with a servo driving mechanism for driving the anvil roll 2 to rotate at a constant speed or at a periodically variable speed, the servo driving mechanism comprises a servo motor 4, a speed reducer 5 and a coupling 6, and the servo motor 4 is connected with the anvil roll 2 through the speed reducer 5 and the coupling 6.

When the pattern part 3 on the anvil roll 2 passes through the end face 7 of the ultrasonic horn 1, the linear speed of the surface of the anvil roll 2 is equal to the linear speed of the traveling sheet material 101 under the action of the servo motor 4.

The circumference of one rotation of the anvil roll 2 is S0, and the interval between adjacent pre-welding areas 102 is S1.

1) When S0/N is equal to S1, the anvil roll 2 rotates at a constant speed.

2) When S0/N is not equal to S1, the anvil roll 2 rotates at a periodic speed change, and at the time, the anvil roll 2 performs N speed change cycles each time the anvil roll 2 rotates one turn, each speed change cycle comprises a constant speed section g1 and a speed change section, the angle of the constant speed section g1 is 20-50 degrees, and the angle of the speed change section is 360 degrees/N-g 1.

Specifically, when S0/N > S1, the anvil roll performs N speed change cycles every time the anvil roll rotates, each speed change cycle comprises a low speed uniform section and a speed change section, the pattern part passes through the end face of the ultrasonic welding head in the low speed uniform section in the speed change cycle, the angle g1 of the low speed uniform section is 20-50 degrees, and the angle of the speed change section is 360 degrees/N-g 1;

when S0/N < S1, the anvil roll performs N variable speed cycles every time the anvil roll rotates, each variable speed cycle comprises a high-speed constant speed section and a variable speed section, the pattern part passes through the end face of the ultrasonic welding head in the high-speed constant speed section in the variable speed cycle, the angle g1 of the high-speed constant speed section is 20-50 degrees, and the angle of the variable speed section is 360 degrees/N-g 1.

More specifically, as shown in fig. 4 and 10, an ultrasonic welding apparatus is used for intermittently welding a plurality of pre-welding areas 102 arranged at equal intervals on a sheet material strip 101. Wherein the anvil roll 2 has a centre of rotation O1 and the ultrasonic horn has an end face 7 which imparts welding energy to the material. Further comprising: a first structural intersection line L1 passing through the rotation center O1 and perpendicular to the ultrasonic-tip end face 7, and a second structural intersection line L2 located at a middle position O3 of the ultrasonic-tip end face 7 and perpendicular to the ultrasonic-tip end face 7, the first structural intersection line L1 and the second structural intersection line L2 being parallel to each other, and the first structural intersection line L1 being offset in the downstream direction with respect to the second structural intersection line L2. By arranging the first construction intersection line L1 to be offset towards the downstream side relative to the second construction intersection line L2, the initial compression gap B2 when the welding material enters the welding area is increased, and B2> B1, so that the risk of cutting off the material in the welding process is effectively prevented, and meanwhile, the welding strength is improved.

The first construction intersection L1 is offset from the second construction intersection L2 by a distance X of 2-5 mm. The distance Y from the anvil roll 2 to the end face of the ultrasonic horn 1 is 0.01 to 0.1 mm.

The angle bisector of the uniform velocity interval g1 coincides with the first structural intersection line L1. The uniform speed intervals g1 are symmetrically distributed by taking the first structure intersection line L1 as a symmetrical line. When the first construction intersection line L1 coincides with the second construction intersection line L2, the center of rotation O1 of the anvil roll, the center point O2 of the pattern part, and the center point O3 of the ultrasonic horn end face 7 are on the same straight line, which, although enabling welding, risks the material being cut off during welding. Therefore, the first construction intersection L1 is preferably offset with respect to the second construction intersection L2.

In order to prevent the product from shaking and the adverse effect of wrinkle on ultrasonic welding, belt pressing mechanisms are respectively arranged before and after the welding station of the sheet material strip 101, and the sheet material strip passes through the belt pressing mechanism at the inlet side, then passes through the ultrasonic welding station and then is output through the belt pressing mechanism at the outlet side in the advancing process.

The ultrasonic welding device is further described below with reference to fig. 3.

As shown in fig. 3, an ultrasonic welding apparatus for intermittently welding a plurality of pre-welding areas 102 arranged at equal intervals on a sheet material strip 101 has a welding station 103 and a holding station 104 for holding the sheet material strip.

The clamping station is described in detail below.

The clamping stations 104 are respectively arranged at the upstream side and the downstream side of the welding station 103, and are provided with belt press-feeding mechanisms for ensuring the flatness and the tension of the sheet material strip 101, the belt press-feeding mechanisms comprise an upper pressing belt 8 and a lower pressing belt 9, the rotation of the upper pressing belt 8 and the rotation of the lower pressing belt 9 are both driven by power, and the surface linear velocities of the upper pressing belt 8 and the lower pressing belt 9 are the same. The upper pressing belt 8 can move up and down in a vertical plane relative to the lower pressing belt 9, and during operation, the upper pressing belt 8 applies a pressure to the lower pressing belt 9, and the pressure is adjustable.

The two belt press-feed mechanisms are provided, and include a first belt press-feed mechanism 105 located on the upstream side of the welding station 103 and a second belt press-feed mechanism 106 located on the downstream side of the welding station. Wherein the belt surface line speed of the second belt pressure feeding mechanism 106 is greater than or equal to the belt surface line speed of the first belt pressure feeding mechanism 105.

In the case of the example 1, the following examples are given,

when the number of pattern portions N on the surface of the anvil roll is 2, the circumferential length S0 of one rotation of the anvil roll is 800mm, the pitch S1 of the pre-welded region on the surface of the sheet material strip is 300mm, and g1 is 40 °, the angular displacement-time curve and the angular velocity-time curve required for the speed change of the anvil roll at a production speed of 600 sheets per minute are shown in fig. 5 to 6.

In the case of the example 2, the following examples are given,

the angular displacement-time curve and angular velocity-time curve required for the anvil roll shift are shown in fig. 7 to 8, taking the interval S1 between the welding areas on the surface of the sheet strip as 500mm, and the rest of the parameters are the same as in example 1.

The above description and the drawings only show the preferred embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can appreciate that the technical solutions and the inventive concepts of the present invention can be equally replaced or changed within the technical scope of the present invention.

Claims

1. An ultrasonic welding device for intermittently welding a plurality of pre-welding areas arranged at equal intervals on a sheet material strip, which comprises an ultrasonic horn and an anvil roller matched with the ultrasonic horn, wherein the sheet material strip is continuously conveyed to a gap between the ultrasonic horn and the anvil roller from an upstream side to a downstream side to be welded with each other, the anvil roller has a rotation center, and the ultrasonic horn has an end face for giving welding energy to materials; the method is characterized in that: the ultrasonic welding head further comprises a first structure intersection line passing through the rotation center and perpendicular to the end face of the ultrasonic welding head, and a second structure intersection line located in the middle of the end face of the ultrasonic welding head and perpendicular to the end face of the ultrasonic welding head, wherein the first structure intersection line and the second structure intersection line are parallel to each other, and the first structure intersection line is offset towards the downstream side relative to the second structure intersection line.

2. An ultrasonic welding apparatus as defined in claim 1, wherein: the first construction intersection is offset from the second construction intersection by a distance of 2-5 mm.

3. An ultrasonic welding apparatus as defined in claim 1, wherein: the distance from the anvil roll to the end face of the ultrasonic welding head is 0.01-0.1 mm.

4. An ultrasonic welding apparatus as defined in claim 1, wherein: the anvil roll is correspondingly provided with N pattern parts and also comprises a servo driving mechanism for driving the anvil roll to rotate at a constant speed or at a periodic variable speed; when the pattern on the anvil roll passes through the end face of the ultrasonic welding head, the linear speed of the surface of the anvil roll is equal to the linear speed of the sheet material strip under the action of the servo driving mechanism.

5. An ultrasonic welding apparatus as defined in claim 4, wherein: the servo driving mechanism comprises a servo motor, a speed reducer and a coupler, and the servo motor is connected with the anvil roll through the speed reducer and the coupler.

6. An ultrasonic welding apparatus as defined in claim 4, wherein: when the anvil roll rotates at a periodic variable speed, the anvil roll performs N variable speed cycles every time the anvil roll rotates for one circle, each variable speed cycle comprises a constant speed interval and a variable speed interval, the angle of the constant speed interval is 20-50 degrees, and the bisector of the constant speed interval coincides with the intersecting line of the first structure.

7. The ultrasonic welding apparatus of any one of claims 4 to 6, wherein: the circumference of one rotation of the anvil roll is S0, and the distance between the adjacent pre-welding areas is S1; when S0/N is equal to S1, the anvil roller rotates at a constant speed, and when S0/N is not equal to S1, the anvil roller rotates at a periodically variable speed.

8. An ultrasonic welding apparatus as defined in claim 1, wherein: the ultrasonic welding device is provided with a welding station consisting of an ultrasonic welding head and an anvil roller, and a clamping station for holding the sheet material strip; the clamping stations are respectively arranged at the upstream side and the downstream side of the welding station and are provided with belt pressure feeding mechanisms for ensuring the flatness and the tension of the sheet material strips.

9. An ultrasonic welding apparatus as defined in claim 8, wherein: the belt pressure feeding mechanism comprises an upper pressure belt and a lower pressure belt, the rotation of the upper pressure belt and the rotation of the lower pressure belt are both driven by power, and the surface linear velocities of the upper pressure belt and the lower pressure belt are the same.

10. An ultrasonic welding apparatus as defined in claim 9, wherein: the upper pressing belt can move up and down in a vertical plane relative to the lower pressing belt, and exerts pressure on the lower pressing belt in the working process, and the pressure is adjustable.