JPH06122406A - Bag mouth folding method - Google Patents

Abstract

PURPOSE:To fold flatly the opening of a gusset bag of which the opening surface is square, without being twisted. CONSTITUTION:A pair of inhibiting members 13, 14 which are inserted in a bag along the inner sides of the front surface and back surface of the bag have an elastic restoring force which tries to separate from each other to a compelling force from the outside. When folding pleats at the centers on both side surfaces of the bag are pushed in by a pair of push-in members 24, 25 to the inside of the bag, the pair of the inhibiting members try to separate by the nearing of the front and back surfaces of the bag, the bag mouth can be folded under a stretched condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for folding an open mouth portion of a gusset bag into an empty bag state, and more particularly to a method for flatly folding an opening portion of a gusset bag filled with an article to be sealed for sealing. Regarding

[0002]

2. Description of the Related Art As shown in FIG. 5, a gusset bag (1) having folding folds (2) and (3) at the center of both sides has a habit of restoring to its original shape when it is an empty bag. Although no problem occurs, in the case of a gusset bag filled with an object to be packaged, the habit of restoring its original shape to the opening is lost. Therefore, as disclosed in Japanese Patent Publication No. 60-13882, a pair of holding plates (4) are provided from the front and the back of the bag to fold the opening of the gusset bag filled with the object to be packaged.
Simultaneously with approaching (5), it is necessary to approach the pair of spatula plates (6) (7) toward the folding folds (2) (3). Also, in Japanese Utility Model Publication No. 46-7015, the suction force of the air cylinder (8) is applied while the bag surface is attracted to both pressing plates by the vacuum suction force acting on the opposing surfaces of the pressing plates (4) and (5). It discloses that the front and back of the bag are brought close to each other.

[0003]

However, in the case of the above-mentioned conventional method, the timings and speeds of approaching the pressing plates (4) (5) and the spatula plates (6) (7) must correspond to each other. However, if these requirements are deviated, the bag mouth may be twisted and folded because the object to be packaged is filled. That is, when the pair of pressing plates (4) (5) are brought close to each other at a constant speed, the folding folds (2) (3) on both sides are initially gentle and gradually accelerate to be folded. The approaching speed of the spatula plates (6) (7) must also be gradually accelerated according to the speed of the folding folds (2) (3), so it is very difficult to control the corresponding speed between the pressing plate and the spatula plate. There was a drawback. This problem becomes more difficult especially when the size of the bag changes.

[0004]

SUMMARY OF THE INVENTION In view of the above points, the present invention is such that the gusset bag front and rear approaching speeds and the folding fold folding speeds on both sides always correspond to each other, and the object to be packaged is inflated. A method for folding a bag mouth of a gazette bag without twisting, which is a method of folding a folding fold at the center of each of the both side surfaces of a gazette bag having four sides including a front surface, a back surface, and both side surfaces. A pair of suppressing members that match the respective widths of the front surface and the back surface of the bag and exhibit an elastic restoring force in the direction of separating against the forcing force are inserted along the inside of each of the front surface and the back surface, The folding folds at the center of both side surfaces of the bag are pushed into the bag by a pair of pushing members against the elastic restoring force of the restraining members.

[0005]

The pair of restraining members inserted inside the front and back sides of the bag have a characteristic that they always open due to the elastic restoring force, so that the pair of pushing members resist the elastic restoring force and the folding folds of the bag. By pushing in, the pair of restraining members approach each other so as to follow the movement of the pushing members, and the elastic restoring force acts on the bag mouth as a reaction force, so that the pair of restraining members are folded flat in a tense state.

[0006]

[Example] As shown in FIG.
(11) A pair of leaf spring restraining members (13) (14) vertically suspended from the support bar (12) in a gusset bag (10) filled with
Insert. If a forcing force (15) (16) is applied to these restraining members (13) (14) from the outside, the restraining members (13) (14) will restore to their original state against these forcing forces. It has the property of exhibiting elastic restoring force (17). As shown in FIG. 2, the widths (21) of the restraining members (13) and (14) are slightly smaller than the widths (20) of the front (18) and the back (19) of the gusset bag (10). A notch (22) is formed in the center of the lower surface of the suppressing member. As shown in FIG. 1, a part (23) of both restraining members is narrowly curved outward, and the curved leaf spring part (2
3) exhibits resilience. In this state, the pair of spatula-shaped pushing members (24) (25) are brought close to each other, and the folding folds (2
6) When (27) is pushed into the inside, the front surface and the back surface of the bag come close to each other while pressing both restraining members having a restoring force in the separating direction. Therefore, the bag mouth can be flatly folded in a tense state. In this case, when the elastic member (30) is interposed between the pushing members (24) and (25) as shown in FIG. 2, it is possible to prevent the pushing member from breaking through the bag due to its cushioning action. After that, as shown in Fig. 4, the holding member (3) with a length that overlaps the folding folds (26) (27) on both sides at the notch
After the mouth of the bag (10) is flatly sandwiched by 1) and the restraining member (13) and the pushing members (24) and (25) are retracted, the bag mouth can be heat-sealed and sealed.

[0007]

[Effect] When the folding folds on both sides of the bag are pushed into the inside of the bag by the pair of pushing members, the pair of suppressing members having elastic restoring force in the separating direction are pushed toward the bag surface. These control members move automatically following the movement of the pushing member, and the movements of both members always correspond while tensioning the bag, so the bag mouth is folded flat without twisting, resulting in wrinkling. It has the effect of creating a beautiful seal.

[Brief description of drawings]

FIG. 1 is a perspective view showing a folded state.

FIG. 2 is an explanatory diagram of a previous step of the previous figure.

FIG. 3 is a side view.

FIG. 4 is a front view.

FIG. 5 is an explanatory diagram of a conventional example.

[Explanation of symbols]

(13) (14) ... Suppression member (24) (25) ... Pushing member
(31)… Clamping material

Claims (2)

[Claims] 1. A method for folding a folding fold at the center of each of the two side surfaces of a gusset bag having four surfaces, a front surface, a back surface, and both side surfaces, wherein the width of each of the front and back sides of the bag is equal to the width of the bag. And a pair of restraining members that exert elastic restoring force in the direction of separating against the forcing force are inserted along the inside of each of the front surface and the back surface, and a pair of fold folds at the center of both side surfaces of the bag are pushed in. A method for folding a bag mouth, wherein the member is pushed into the bag against the elastic restoring force of the both restraining members. 2. A method for folding a folding fold at a central portion of each of both side surfaces of a gusset bag having a front surface, a back surface and both side surfaces, the width of each of the front and back surfaces being equal to each other. And a pair of restraining members that exert elastic restoring force in the direction of separating against the forcing force are inserted along the inside of each of the front surface and the back surface, and a pair of fold folds at the center of both side surfaces of the bag are pushed in. After pushing the bag inside the bag against the elastic restoring force of the both restraining members, the holding member that overlaps the folded folds is used to hold the bag from the front and back while pressing the restraining member and the pushing member. How to fold the bag mouth so that it can be retracted to the outside.