EP0046591A2

EP0046591A2 - Method of and apparatus for gathering end portions of wrapping tubes

Info

Publication number: EP0046591A2
Application number: EP81106585A
Authority: EP
Inventors: Eiichi Sato
Original assignee: OSAKA KAGAKU GOKIN KK
Current assignee: OSAKA KAGAKU GOKIN KK
Priority date: 1980-08-26
Filing date: 1981-08-25
Publication date: 1982-03-03
Also published as: JPS5746718A; AU7435881A; DE3167474D1; EP0046591B1; ZA815791B; KR830006070A; ATE10471T1; JPS6317690B2; EP0046591A3

Abstract

A circular open end portion of a ham-wrapping tube, before clipping the same with rings, is compressed by regulating elements at two diametrically opposite regions thereof toward the center of a cross section of the tube-end, until the distance between these regions has been shortened to a level equal to the width of each of folds to be formed in the tube-end.

Thereafter, the narrowed tube-end is compressed by gathering rods at two opposite corner regions thereof at once toward the center of a cross section of the narrowed tube-end.

Thus, the tube-end can be gathering in zigzags.

Description

This invention relates to a method of and an apparatus for gathering in zigzags open end portions of a tube consisting of a comparatively soft material and, more particularly, to a method of and an apparatus for gathering in zigzags conveniently open ends of a ham-wrapping tube before clipping the same with rings.
A single-layer tube or a multi-layer tube consisting of film of a thermally contractible synthetic resin, such as saran film, is used in a ham-wrapping operation. In order to bind both of open mouth portions of such a tube, each of the mouth portions is drawn to the center of a cross section thereof, and both of the resulting centralized mouth portions are held firmly with U-shaped clips so as to prevent the air from entering the tube.
Such tube-end gathering operations have mostly been put into the hands of workers. This hinders the speed-up of a ham-wrapping operation, and makes it difficult to carry out the mass production of wrapped ham. Moreover, such a manual tube-end gathering operation has been an obstacle to the automation of a series of ham-packaging steps including a ham-sacking step and a tube-end seal-cutting step. A mouth portion of a ham-wrapped tube, which has been gathered randomly, cannot be sealed well. The reason is that a randomly gathered mouth portion of a sack has too many pleats or folds, through narrow spaces among which a small amount of air leaks to cause the freshness of the ham in the sack to be decreased. Therefore, in order to seal a ham-wrapped tube reliably, it is necessary to reduce the number of folds at mouth portions thereof to as great an extent as possible. It is desirable that each mouth portion be folded in zigzags in good order in such a manner that each of the folds has the same and the largest possible width, which is, however, small enough to allow the mouth portion to be inserted through a U-shaped clip. However, a tube-end gathering method, in which orderly folds may be obtained at end portions of a tube, and in which a circular end portion of a tube is gathered centripetally in all directions at once, would not have a good effect. In such a method, folds in an end portion of a tube would collide with one another irregularly in a final stage of a tube-end gathering operation.
A primary object of the present invention is to provide a novel, automatic tube-end gathering apparatus which permits gathering mouth portions of a wrapping tube in a regularly folded state in such a manner that each of the folds has a predetermined width, and which permits no leakage of air to occur at mouth portions of the resulting sack after the mouth portions of the sack have been bound.
A second object of the present invention is to provide a novel tube-end gathering apparatus capable of gathering mouth portions of a wrapping tube automatically, easily and reliably, which permits being constructed very simply at a low cost, and which is free from being erroneously operated.
A third object of the present invention is to provided a novel tube-end gathering apparatus which can be utilized easily for carrying out one step, for example, a ham-sacking step, among a series of ham-packaging steps.
The gist of the idea of the present invention resides in the following. The tube-end gathering method according to the present invention is not such that a circular open end portion of a wrapping tube is drawn centripetally in all directions at once, nor is it such that a circular open end portion of a wrapping tube is pressed at two diametrically opposite regions thereof against each of these regions to thereby cause the end portion of the tube to be closed completely in a straight line with the resulting closed end portion of the tube thereafter folded to a predetermined width. According to the present invention, a circular open end portion of a wrapping tube is compressed at two diametrically opposite regions thereof toward each of these regions as the opposite regions are kept parallel to each other, until the distance between the opposite regions, i.e. the width of the narrowed opening in the end portion thus compressed of the tube has become equal to the width of each of folds to be formed in this end portion of the tube; and then, the narrowed end portion of the tube is compressed at two opposite corner regions thereof at once toward the center of the narrowed opening in the end portion of the tube, i.e. in a direction at right angle to the direction in which the first tube-end compressing step has been carried out.
The above and other objects as well as advantageaus features of the invention will become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings.

Fig. 1 is a front elevational view of a first embodiment of the present invention;
Fig. 2 is a front elevational view in section of a second embodiment of the present invention; and
Fig. 3-6 are front elevational view of the embodiment shown in Fig. 1, illustrating the procedure of an automatic tube-end gathering operation.

The construction of the present invention will be described in detail with reference to an embodiment thereof.
A pair of parallel machine frames 7, 8 are provided, and. another pair of machine frames 9, 10 between opposite ends of the machine frames 7, 8. A rectangular frame is thus formed with these four machine frames, and a wrapping tube is inserted into the rectangular frame with a circular open end portion 11 of the tube positioned in the central portion of the rectangular frame.
Regulating elements 12, 13 are provided on the inner side of the machine frames 7, 8, and front end portions of piston rods 16, 17 in air cylinders 14, 15 are secured to outer surfaces of the regulating elements. The air cylinders 14, 15 are joined to the machine frames 7, 8, respectively. In order that the regulating elements 12, 13 can be displaced parallel to each other with both end surfaces of both thereof moving along the machine frames 9, 10, guide rods 18, 19, which are parallel to the piston rods 16, 17, are extended from the outer surfaces of the regulating elements 12, 13. The guide rods 18, 19 are supported in guide bores 20, 21 provided on the machine frames 9, 10.
Each of the second machine frames 9, 10 is provided with a bore in the central portion thereof. Gathering rods 22, 23 are provided in an opposed relationship in the bores in the machine frames 9, 10 in such a manner that the gathering rods can be extended toward the center of the circular open end portion 11. The gathering rods 22, 23 are connected at their respective outer ends to piston rods 26, 27 in air cylinders 24, 25.
Both of the regulating elements 12, 13 employed in the embodiment shown in Fig. 1 are movable. Only one 12 of the regulating elements 12, 13 movable with the other 13 consisting of a stationary regulating element.
The operation of the present invention will now be described.
When a circular open end portion 11 of a wrapping tube is inserted in the rectangular frame consisting of the machine frames 7, 8, 9, 10, the insertion is detected by a sensor (not shown). The air cylinders 14, 15 are then actuated in accordance with an instruction given by a detection signal from the sensor, so that the piston rods 16, 17 are extended. As a result, the regulating elements 12, 13, which are joined to the piston rods 16, 17, respectively, are moved toward each other. The movements of the regulating elements 12, 13 are stopped when the distance therebetween has been shortened to a level equal to the width of each of folds to be formed on the end portion 11 of the wrapping tube. While the regulating elements 12, 13 are thus displaced, the end portion 11 of the wrapping tube, which has been in a circularly opened state (refer to Fig. 3), is narrowed in an elongated half-opened state 11a as shown in Fig. 4.
The completion of displacement of the regulating elements 12, 13 is detected by a sensor (not shown). The air cylinders 24, 25 are actuated in accordance with an instruction given by a detection signal from the sensor to allow the piston rods 26, 27 to be extended. As a result, the gathering rods 22, 23, which are joined to the piston rods 26, 27, are displaced toward each other as shown in Fig. 5, along a space which has been formed by the regulating elements 12, 13 and which has a width equal to the width of each of the folds to be formed.
Owing to the displacements of the gathering rods 22, 23 toward each other, the end of the tube in an elongated half-opened state 11a is compressed from both sides thereof at an equal pressure. As a result, the end portion of the tube is narrowed within the limited width defined by the regulating elements 12, 13 as the end portion of the tube is held between these elements 12, 13. Accordingly, the end portion of the tube is folded in zigzags 11b while forming pleats of a constant width (refer to Fig. 5).
When the displacement of the gathering rods 22, 23 toward each other has further progressed, so that the gathering rods 22, 23 reach their limit position as shown in Fig. 6, the adjacent pleats in the end portion folded in zigzags lib of the tube get close to one another. In other words, the end portion of the tube looks like a folded fan, in which the pleats are in close contact with one another with no gaps left among them (refer to Fig. 6).
After the tube-end gathering operation has been completed, the gathered end portion of the tube is knotted or bound. A description of a gathered-end knotting or binding operation will be omitted since such an operation is out of the scope of the present invention.
As soon as a gathered-end knotting or binding operation has been completed, air is introduced into opposite ports of the air cylinders 14, 15, 24, 25, so that parts of this tube-end gathering apparatus are returned to their original positions shown in Fig. 1.
In the tube-end gathering apparatus according to the present invention having the above-mentioned construction and operation, a circular open end portion of a wrapping tube is compressed initially at two diametrically oppsite regions thereof toward each of these regions until the distance between these two regions has been shortened to a level which is equal to the width of each of folds to be formed in the end portion of the tube, and thereafter compressing the end portion thus narrowed of the tube at two corner regions thereof toward each of the regions within the narrowed space having a width equal to folds to be formed. As a result, the end portion of the tube is folded in good order with the pleats contacting one another in the manner of a folded fan. Thereafter, after the gathered end portions of the tube have been bound, the air in the sack does not leak through the bound end portions thereof. This allows a decrease in the quality of the content, especially, ham, in the sack, which is ascribable to the leakage of air through the bound end portions of a sack, to be prevented substantially perfectly. Moreover, such gathered end portions of a ham-wrapping tube can be obtained by using an apparatus shown in the drawings, which can be constructed very simply at a low cost. This tube-end gathering apparatus can be operated very simply and understandably, so that a tube-end gathering operation can be carried out without fail. In fact, this apparatus permits obtaining desired effect reliably. In addition, this apparatus has many other remarkable effects; it can be connected operatively with ease to a knotting means, or employed for carrying out one of a series of automatic packaging steps.
The present invention is not, of course, limited to the above embodiments; it may be modified in various ways within the scope of the appended claims.

Claims

1. A method of gathering end portions of wrapping tubes, comprising the steps of compressing a circular open end portion of a wrapping tube at two diametrically opposite regions thereof toward the center of a cross section of the end portion of the tube while keeping these regions parallel to each other, until the distance between these regions has been shortened to a level equal to the width of each of folds to be formed in the end portion of the tube; and thereafter compressing the end portion thus narrowed of the tube at two opposite corner regions thereof at once toward the center of a cross section of the narrowed end portion of the tube.

2. A tube-end gathering apparatus comprising a rectangular frame having an open space inside thereof which is large enough to insert therethrough a circular open end portion of a wrapping tube, regulating elements provided on the inner side of two parallel opposite beams, respectively, of said rectangular frame, actuator means capable of parallel-displacing said pair of regulating elements toward each other to positions in which the distance between said regulating elements is shortened to a level equal to the width of each of folds to be formed in the end portion of the tube, a pair of gathering rods extended toward the center of said rectangular frame from intermediate portions of the remaining two parallel opposite beams of said rectangular frame, and means capable of displacing said gathering rods toward each other by utilizing said regulating elements as guides when said regulating -elements are in the closest positions with respect to each other.

3. A tube-end gathering apparatus according to claim 2, wherein both of said regulating elements are displaceable.

4. A tube-end gathering apparatus according to claim 2, wherein only one of said regulating elements is displaceable.