JPH09156616A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent wrinkles from remaining in a packing body after a bag is formed, by avoiding wrinkles to be generated in a resin film at the time of fixing by a pressing material and a receiving material without making a structure extremely complicated. SOLUTION: In each of a pair of pinching bodies 12 and 22 which are arranged in an opposing arrangement by pinching a cylindrical resin film 31b, tension means 17 and 27 are provided. When the pinching bodies 12 and 22 approach, two parts of the resin film 31b in the cross direction is fixed by the tension means 17 and 27 before a pressing material 45 and a receiving material 55 fix the resin film 31b. When the pinching bodies 12 and 22 approach further, the fixed interval between the tension means 17 and 27 is extended, so that the resin film 31b is tensioned in the cross direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device used for sealing an open end of a tubular resin film.

[0002]

2. Description of the Related Art A packaging machine for continuously forming a bag-shaped package from a sheet-shaped resin film and storing an article to be packaged such as a machine component therein has been put into practical use. As shown in FIG. 8, this packaging machine uses a sheet-shaped resin film (31
(a: Fig. a) is rounded (Fig. b), and the overlapped ends are welded to each other to form a tubular resin film (31b) (Fig. c), and the lower opening of the tubular resin film (31b) is welded and sealed. The item to be stored (32) is thrown into the inside (Fig. D), the upper opening is welded and sealed (Fig. E), and the sealed portion is cut along the width direction of the bag to be packaged. A package (33) of the article (32) is obtained (Fig. F).

In each of the steps of sealing the upper and lower openings of the tubular resin film (FIGS. D and e), the horizontal sealing device (40) shown in FIG. 6 is used. The sealing device (40) includes a pair of holding bodies (42) with a tubular resin film (31b) intermittently transferred from the upper side to the lower side sandwiched therebetween.
(52) are arranged opposite to each other, and the holding bodies (42) (52) are horizontally driven by drive mechanisms (60) (61) arranged on both sides thereof to weld and cut the tubular resin film (31b). Is.

The drive mechanism (60) (61) is formed by connecting two drive chains (62) (63) and two connecting bodies (64) (65) interposed therebetween in a loop shape. It Both chains (62) (63) are meshed with two sprockets (66) (67) arranged on the sides of the holding body (42) (52), respectively. The chains (62) (63) and the sprocket The drive mechanisms (60) and (61) rotate in the forward and reverse directions within the range where the (66) and (67) mesh with each other. Drive mechanism (6
0) (61), the lower connecting body (64) is connected to one holding body (first holding body (42)), and the upper connecting body (6).
5) is connected to the other holding body (the second holding body (52)).

A rotary drive source (68) such as a motor is connected to one (60) of the two drive mechanisms (60) (61), and the rotary drive source (68) is activated. The drive mechanism (60) rotates in one direction, for example, counterclockwise to slide the two holding bodies (42) (52) in the approaching direction. Along with this, the upper connecting body (65) and the base (6
The spring (70) arranged between the spring and (9) expands and stores elastic force. When the rotary drive source (68) is stopped, the elastic force accumulated in the spring (70) causes the drive mechanisms (60) (61) to reverse clockwise, and as a result, the two holding bodies (42) (52) are It separates and returns to the initial position.

As shown in FIGS. 7A and 7B, of the two holding bodies (42) and (52), the first holding body (42) is the second holding body (42).
The heater (43) (43) vertically spaced apart is provided on the surface facing the holding body (52). This heater (43) (43)
Are attached to the front end surfaces of the bifurcated portions of the bifurcated heater body (44) that is branched up and down, and are connected to a power supply device (not shown). Pressing members (45) (45) supported so as to be slidable parallel to the sliding direction (horizontal direction) of the holding bodies (42) (52) are provided on the upper and lower surfaces of the heater body (44). The elastic member (46) (4) (4) (4) is formed between the pressing member (45) and the base of the heater body (44).
6) are installed respectively. Both holding bodies (42) (52)
When they are separated from each other, the tip surfaces of the two pressing members (45) are located at a position projecting toward the tubular resin film (31b) side with respect to the heater (43).

The second holding body (52) is the first holding body (4).
It has a cutter (53) at the portion facing 2). This cutter (53) is the heater (43) (43) of the heater body (44).
Aiming at the storage space (47) formed between them, the cutter body (5
It is mounted on 4) and follows the horizontal reciprocating motion of the cutter body (54) to perform the reciprocating motion in the horizontal direction. At the upper and lower corners on the tip side of the cutter body (54), L-shaped receiving members (55) (55) (55) are supported so as to be slidable in parallel with the approaching / separating directions of the holding bodies (42) (52). ) Is placed,
The elastic member (56) (56) such as a coil spring interposed between the receiving member (55) and the cutter body (54) causes the receiving member (55) to elastically move to the second holding body (52). Supported by the public. Both of the receiving members (55) are arranged so that a part thereof covers the upper and lower ends of the front surface of the cutter body (54), and the lower ends of the upper receiving member (55) and the lower receiving member (55) are The cutter (53) projects from the gap between the lower end.

The upper holding member (45) and the receiving member (55), and the lower holding member (45) and the receiving member (55) form a holding mechanism (49), respectively. This pressing mechanism (49) is intended to facilitate these operations by positioning and fixing the film so that it will not be displaced during welding and cutting of the resin film.

In the above structure, the two holding bodies (42) (5
When 2) is approached, first, the upper and lower holding members (45) and the receiving members (55) of the two holding bodies (42) (52) come into contact with each other, and the tubular resin film (31b) is placed at the two upper and lower positions. Also, it is fixed in the entire width direction. Further, when the holding bodies (42) (52) are brought closer to each other, the elastic members (46) (56) are respectively compressed, and the holding material (45) and the receiving material (55) are tubular resin films (31b).
Heater body (44) and cutter body (54) while being in pressure contact with
Retreat relative to.

Along with this, the heater (43) approaches or contacts the tubular resin film (31b) to heat the resin film and weld the overlapped films together. This allows
The tubular resin film (31b) is sealed at two upper and lower positions, and the upper opening of the packaging body (33: see FIG. 8) and the lower opening of the tubular resin film (31b) following it are simultaneously sealed.
At the same time, the cutter (53) cuts the resin film (31b) in the width direction between the upper and lower sealing portions to cut out the package (33).

[0011]

In the bag making process, when the pressing material and the receiving material approach each other, the tubular resin film pressed by the pressing material gradually deforms into a flat shape. At this time, since there is a large difference in the approaching amount of the resin films between the portion that comes into contact with the pressing material and the receiving material and the portion that does not come into contact therewith, axial wrinkles are likely to be formed in the film. Since the conventional sealing device does not take special measures against wrinkles, a large number of wrinkles may remain in the packaged product, which may reduce the airtightness at the sealing part or cause a gap in the sealing part. This caused problems such as the packaged items leaking to the outside.

Therefore, an object of the present invention is to reliably prevent the generation of wrinkles at the time of sealing the openings at both ends of the tubular resin film and to ensure the airtightness of the package.

[0013]

In order to achieve the above object,
In the present invention, a pair of holding bodies provided to be able to approach and separate at opposing positions sandwiching the tubular resin film, and a holding member provided on any one of the holding bodies and provided on the other holding body. A holding mechanism that consists of a receiving material and holds the tubular resin film by the holding material and the receiving material when both holding bodies approach each other, and a holding mechanism, and the opening of the tubular resin film fixed by the holding mechanism in the width direction. And a closing means for closing the holding means, the first tensioning means is provided on one holding body and the second tensioning means is provided on the other holding body, and both tensioning means are provided when the holding bodies approach each other. Prior to fixing the resin film by the pressing member and the receiving member, the resin film is fixed at two positions in the width direction, and when the two holding bodies are further approached, the fixing interval is expanded to tension the resin film in the width direction. To let It was.

Here, as an example of the "sealing means", in addition to the above-mentioned heater that is heat-welded, any means that can seal the opening of the resin film, such as one that uses an adhesive, is applicable. .

Specifically, the first tensioning means is provided with the first contact material which is spaced apart at two positions in the width direction of the resin film and precedes the pressing material on the approaching direction side, and at the same time,
The second contact member is provided in the tensioning means of the second contact member in opposition to the first contact member and ahead of the receiving member in the approaching direction side, and the width direction interval between the two contact members is increased when the two contact members are pressed against each other. It is elastically supported so that

More specifically, the first contact member is supported by the first support member having the pair of first elastic portions, and the second contact member is also provided with the pair of second elastic portions. It is supported by the second supporting member that is provided, and both supporting members are arranged such that the distance between the first elastic portions and the distance between the second elastic portions are increased toward the approaching side.

Further, the first and second support members are formed by bending a long metal plate so as to draw a U-shape with its edge portion widening, and its longitudinal direction is the width direction of the resin film. It may be attached to both holding bodies while standing upright and vertically.

In addition, each of the first and second support members may be attached to each holding body via a mounting member arranged so as to cover the upper space of both holding bodies.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to FIG.
A description will be given based on FIGS.

1 and 2 show the entire structure of the packaging machine (1). As shown in the figure, this packaging machine (1) has a loading port (3) for an object to be packed (32) including machine parts, a loading chute (4) connected to the loading port (3), a film roll ( 5) Sheet-shaped resin film (31)
a) for rounding a), a vertical sealing device (9) for welding the ends of the rolled resin film (31a) to each other, and a horizontal side for sealing the open end of the tubular resin film (31b) A sealing device (10) is provided. The lower end of the chute (4) extends right above the lateral sealing device (10),
The object to be packaged (32) charged into the charging port (3) is supplied into the cylindrical resin film (31b) through the chute (4).

The former (7) is in the shape of a cylinder having upper and lower openings (7a) and (7b) each having a substantially rectangular cross section, and a chute (4) is inserted into the inner diameter of the former. When the resin film (31a) pulled out from the film roll (5) reaches the upper end of the former (7), the resin film (31a) is curved according to the upper end shape, and the inner diameter of the former (7) is overlapped at both ends. It is guided to the portion and becomes a tubular shape (step of FIG. 8B). The cylindrical resin film (31b) passes through the gap between the inner diameter portion of the former (7) and the outer diameter portion of the chute (4), and during this passage, the vertical sealing device (9) is used. The overlapped ends are continuously welded in a strip shape (FIG. 8).
(Step (c)).

The tubular resin film (31b) pulled out from the lower end of the former (7) is transferred to the horizontal sealing device (10), where the opening is sealed and the dividing work is performed (FIGS. 8 (d)-(d)). (Step (f)). This horizontal seal device (10) has the same basic structure as the conventional device,
A cylindrical resin film (31
b) The first holding body (12) and the second holding body which are opposed to each other with the second holding body sandwiched therebetween.
While holding the holding body (22) of the holding body (22), the holding mechanism (49) fixes the resin film (31b), the holding body (12) (22)
The opening of the tubular resin film (31b) is sealed by the heater (43) and the cutter (53) provided on the opposing surfaces of the above, and divided in the width direction to obtain a package. The configuration will be described below focusing on the difference from the conventional device.

In the following description, the "width direction" of the tubular resin film (31b) means the opening end (when the tubular resin film is pressed in the diametrical direction and deformed into a flat plate shape ( It becomes a straight line). The “approaching direction” means the direction in which the two holding bodies (12, 22) approach each other.

As shown in FIGS. 3 and 4, the first holding member (12) has a first tensioning means (17) composed of a first supporting member (15) and a first contact member (16). ) Is the mounting member (1
8) is attached via. The first support member (15) is formed by bending a long thin metal plate (steel plate or the like) so that its edge draws a U-shape with a divergent edge, and its longitudinal direction is the resin film (31b). Is mounted on the front surface of the mounting member (18) in a state of standing vertically in the width direction of the mounting member (18). At this time, the two inclined portions (19) of the first support member (15) (the portion inclined with respect to the width direction of the tubular resin film: hereinafter, referred to as “first elastic portion”) are The distance between the two is arranged so as to increase toward the approach direction side.

The first contact material (16) is made of a material that is not slippery with respect to the resin film, such as rubber, and is formed in a rectangular thin plate shape. The resin film (31b) is provided on both ends of the first support member (15). It is installed parallel to the width direction of. The first contact member (16) is arranged at a position preceding the holding member (45) toward the approaching direction when the holding bodies (12) and (22) are separated from each other. From this positional relationship, the holding body is held. When the (12) and (22) approach each other, the first contact material (16) contacts the resin film (31b) prior to the pressing material (45).

The mounting member (18) is formed by bending a thin steel plate in a step shape. The base end portion of the attachment member (18) is attached to the back surface of the heater body (44), and the tip end portion thereof extends above the heater body (44) and extends to the vicinity of the heater (43). It covers the entire upper space of the first holding body (12). As a result, it is possible to prevent the packaged object from falling into the space between the pressing member (45) and the heater body (44), the storage space (47) between the heaters (43), etc. and being caught between the members, A malfunction can be avoided.

The second tensioning means (27) is provided with a mounting member (2
It is attached to the second holding body (22) via 8). The structure and attachment method of the second tensioning means (27) are the same as those of the first tensioning means (17), and the second supporting member (25) and the second contact members () attached to both ends thereof ( 26) and are composed of. The second contact member (26) is arranged at a position ahead of the receiving member (55) in the approaching direction side when the two holding bodies (12) and (22) are separated from each other, and the two holding bodies (12) and (22). ) Is provided at the opposite position of the first contact material (16) so that the resin film (31b) can be held by the cooperation with the first contact material (16). The two inclined portions of the second support member (25) become the second elastic portion (29), respectively.

The operation of the sealing device according to the present invention will be described below.

When the tubular resin film (31b) passing through the vertical sealing device (9) is fed downward by a predetermined amount by a feeding device (not shown), the rotary drive source (68: see FIG. 6) is activated, and the drive mechanism is driven. (60) (61) is driven to bring both holding bodies (12) (22) close to each other. As a result, the first contact material (16) and the second contact material (26) first contact the tubular resin film (31b) and press it to gradually bring the opposing film inner diameter portions closer to each other. . Next, the holding mechanism (49) including the holding material (45) and the receiving material (55) presses the resin film (31b) in the opposite direction over the entire width direction. Eventually, the inner diameter portions of the resin film (31b) pressed by the first and second contact materials (16) (26) come into contact with each other, and both contact materials (16) (26) strongly adhere to the resin film (31b). It is pressed and restrained at two points in the width direction. Further holding body (12)
When the (22) is brought close to it, as shown in FIGS. 5 (a) and 5 (b), the first and second elastic portions (19) and (29) are deformed to the outside, and both the contact members (16) and (26). The resin film (31b) is held in a tensioned state by widening the distance in the width direction. As a result, a large number of wrinkles in the axial direction (vertical direction) caused by the approaching movement of the pressing member (45) and the receiving member (55) disappear. afterwards,
Further, when the holding bodies (12) (22) are brought closer to each other, the pressing material (45) and the receiving material (55) are pressed against each other with the resin film (31b) sandwiched therebetween, and the resin film (31b) is fixed at the upper and lower two positions. To do. After that, the holding bodies (12) (22) are brought closer to each other, so that the tubular resin film (31b) is welded at the upper and lower two places by the heater (43), and the portion between them is widthwise by the cutter (53). Divided. As a result, the package (33: see FIG. 8 (f)) is separated from the film and discharged to the outside of the device by a chute (not shown).
At the same time, a cylindrical resin film (31
The article (32) to be packed is loaded into the b) from the loading chute (4), and then the tubular resin film (31b) is transferred downward by a predetermined amount, and thereafter, the same procedure is repeated to repeat the package (33).
To make continuous bags.

Thus, according to the present invention, the pressing member (45)
Since the resin film (31b) is tensioned by pulling the resin film (31b) in the width direction by the first and second tensioning means (17) (27) before fixing the resin film (31b) with the receiving member (55). Wrinkles do not occur in the resin film during fixing with the holding material (45) and the receiving material (55), and no wrinkles remain in the package after bag making. Therefore, the airtightness of the package can be ensured, and problems such as leakage of the packaged object can be reliably prevented.

In the above description, the case where the above sealing device is incorporated in the packaging machine (1) having the former, the vertical sealing device and the like has been illustrated, but the scope of application of the present invention is not limited to this, and the former and the former can be used. The present invention is also applicable to the case where the horizontal sealing device is used alone without installing the vertical sealing device.

[0032]

EFFECTS OF THE INVENTION According to the present invention, it is possible to avoid the wrinkles that occur in the resin film during fixing with the pressing material and the receiving material without significantly complicating the structure, and wrinkles remain in the package after bag making. Nor. Therefore, the airtightness of the package can be ensured, and problems such as leakage of the packaged object can be reliably prevented.

Further, both tensioning means are supported by a mounting member which extends from the rear of the both holding bodies to the vicinity of the heater and the cutter, and covers the entire space above the both holding bodies. It is possible to reliably prevent a situation in which the object to be packaged is caught in the internal space of the body, and it is possible to avoid malfunction.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a packaging machine including a sealing device according to the present invention.

FIG. 2 is a side view showing a schematic structure of the packaging machine.

FIG. 3 is a perspective view showing an attachment method when attaching the first tensioning means to the first holding body.

FIG. 4 is a vertical cross-sectional view of a sealing device according to the present invention.

FIG. 5 is a plan view showing the operation of the sealing device according to the present invention.

FIG. 6 is a perspective view of a conventional sealing device.

FIG. 7 is a vertical cross-sectional view showing the operation of a conventional sealing device.

FIG. 8 is a perspective view showing steps of obtaining a package from a sheet-shaped resin film.

[Explanation of symbols]

 12 1st holding body 15 1st support member 16 1st contact material 17 1st tension means 18 Attachment member 19 1st elastic part 22 2nd holding body 25 2nd support member 26 2nd contact material 27 Second tensioning means 28 Mounting member 29 Second elastic part 31b Cylindrical resin film 43 Sealing means (heater) 45 Holding material 49 Holding mechanism 53 Cutter 55 Receiving material

Claims (5)

[Claims] 1. An opposing position sandwiching a tubular resin film,
It consists of a pair of holding bodies that can be approached and separated from each other, a holding material that is provided on one of the holding bodies, and a receiving material that is provided on the other holding body. A cylindrical resin film is clamped by a material to fix the cylindrical resin film, and a sealing means for sealing the opening of the cylindrical resin film fixed by the pressing mechanism in the width direction thereof. The first tensioning means is provided on the body, and the second tensioning means is provided on the other holding body, and both tensioning means are provided before the fixing of the resin film by the pressing material and the receiving material when the two holding bodies approach each other. A sealing device, characterized in that a resin film is fixed at two positions in the width direction thereof, and the fixing interval is expanded when the two holding bodies are further approached to tension the resin film in the width direction. 2. The first tensioning means is provided with a first contact material spaced apart at two positions in the width direction of the resin film and ahead of the pressing material in the approaching direction side, and at the same time, the second tensioning means is provided. , A second contact member is provided so as to face the first contact member and precede the receiving member in the approach direction side, and both contact members are elastic so as to widen the widthwise interval between them when they are pressed. The sealing device according to claim 1, wherein the sealing device is supported mechanically. 3. The first contact member is supported by a first supporting member having a pair of first elastic portions, and the second contact member is also supported by a second supporting member having a pair of second elastic portions. 3. The sealing device according to claim 2, wherein the sealing device is supported by members, and the two supporting members are arranged such that the distance between the first elastic portions and the distance between the second elastic portions are increased toward the approaching side. 4. The first and second support members are formed by bending a long metal plate so as to draw a U-shape with its edge portion widening, and its longitudinal direction is the width direction of the resin film. The sealing device according to claim 3, wherein the sealing device is attached to both holding bodies in a state of standing upright and vertically. 5. Each of the first and second support members,
The sealing device according to claim 3 or 4, wherein the sealing device is attached to each holding body through a mounting member arranged so as to cover each upper space of both holding bodies.