JPS636435B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-sealing device, and more particularly to a belt-type heat-sealing device for heat-sealing the mouth end of a pouch.

2. Description of the Related Art As a heat sealing device for heat sealing the mouth end of a pouch (ie, a bag body) filled with juices, soup, etc., a type using a seal belt as shown in FIG. 1 is usually used. In FIG. 1, 1a and 1b are a pair of opposing first heat bars, which are usually made of brass.
Electric resistance heating elements 1a ₁ and 1b ₁ are built-in. 2
Second heat bars a and 2b are provided to ensure heat sealing, and similarly have built-in electric resistance heating elements 2a ₁ and 2b ₁ .

3a and 3b are a pair of cooling bars facing each other, cooling pipes (for example, water cooling pipes) 3a ₁ and 3b ₁
is built-in. First heat bar 1a, 1b
and the second heat bar 2a, 2b, and the second
heat bars 2a, 2b and cooling bars 3a, 3b
In between, first crimping rolls 4a, 4b and second crimping rolls 5a, 5b are provided, respectively, and the crimping rolls are usually made of stainless steel.

6a and 6b are a pair of endless circulation seal belts, and drive rolls 7a and 7b and guide roll 8
a, 8b, the first heat bar 1a, 1b
, between the first pressure rolls 4a and 4b, between the second heat bars 2a and 2b, and between the second pressure rolls 5
a, 5b and between the cooling bars 3a, 3b, and are arranged so as to move in the direction of the arrow in contact with each other and in contact with each other.

A pouch 9 filled with contents is placed on a conveyor (not shown) via a holder or gripped at both side edges by a gripper and conveyed at the same speed as the seal belts 6a and 6b. The mouth end 9a is sandwiched between the seal belts 6a and 6b in the gap between the guide rolls 8a and 8b, and is heated to a heat-sealable temperature and crimped twice while being conveyed together with the seal belts 6a and 6b. After being repeatedly heat-sealed, it is cooled by cooling bars 3a and 3b to a temperature lower than the heat-sealable temperature, and then sent to the next process.

The seal belts 6a, 6b are usually made of stainless steel, and their widths are usually the same as the heat bars 1a, 1b;
2b, pressure rolls 4a, 4b; contact portions of each of 5a, 5b and cooling bars 3a, 3b (for example, 1
a ₂ , 4a ₁ , 3a ₂ ), that is, approximately equal to the height, and also equal to the width of the heat-sealed portion of the pouch mouth end 9a, which is usually about 10 mm. The thinner the material, the smaller the heat capacity and the higher the heating and cooling rate, so it is preferable, but if it becomes too thin, the strength will decrease, so the thickness is usually about 100 to 300 μm, preferably
It is set at around 150μm.

By the way, each of the seal belts 6a, 6b has a loop shape capable of endless circulation, and this loop is formed by welding both ends of a stainless steel ribbon having the above-mentioned cross-sectional dimensions. However, due to the thin thickness, it is impossible to obtain a durable weld by butt welding. Therefore, in the past, an overlap welded part 10 having a stepped part 10a as shown in FIG.
(By electric resistance welding, the overlapping width is usually 1.0~
1.5mm) was formed by lap welding. Although it is possible to obtain a flat welded part by removing protruding parts such as burrs after fusion welding by electron beam welding, etc., in this case, the welded part becomes brittle and easily breaks, making it impractical.

If there is an overlap weld 10 in the seal belt, as shown in FIG.
- The pressing force applied by the crimping rolls 4a and 4b (the same applies to the crimping rolls 5a and 5b) is not satisfactorily applied to the portion of the mouth end 9a corresponding to the section of y and the section of z-w, and as a result, the part concerned The heat seal strength is weak and it peels easily, and when internal pressure is applied during retort heat sterilization, the part may peel off and the contents leak, or there may be pores from the beginning and outside air may enter the inside. Troubles such as intrusion and spoilage of contents are likely to occur.

It is an object of the present invention to solve the problems of the prior art described above.

To achieve the above object, the present invention includes at least one pair of opposing heat bars, a pressure roll provided downstream of the heat bar, a cooling bar provided downstream of the pressure roll, and the heat bar, the pressure roll, and the pressure roll. A pouch heat sealing apparatus comprising a pair of opposing endlessly circulating metal sealing belts passing between and in contact with each of the cooling bars, the endlessly circulating sealing belts sealing the opposite ends of the metal ribbon. It is formed by joining reinforcing materials to both side edges of the inner surface of the both ends, and the width of the part between the reinforcing materials is the same as that of the heat bar, the pressure roll, and the cooling bar. The present invention provides a pouch heat sealing device characterized in that the width of the pouch is slightly larger than the width of each contact portion.

The present invention will be described below with reference to the drawings which are examples.

The heat sealing device of the present invention includes a seal belt 1
The difference from the conventional device is that the joint portions 15a and 15b of the heat bar 6a and 16b are not overlap welded portions, and the structure of the other heat bars is the same as that of the conventional heat bar.

As shown in FIGS. 3, 4, and 5, the seal belt 16a is made by abutting the end surfaces of both ends 16a ₁ and 16a ₂ of a metal ribbon (usually made of stainless steel, approximately 100 to 300 μm thick). (Butt welding may be performed at that time, but a durable joint cannot _be obtained by butt welding _alone .) heat bar 1a
An endless circulation belt is formed by joining reinforcing materials 17 to the upper and lower edges of the surface (the side that contacts the belt) by spot welding or fillet welding. The seal belt 16b is also formed in the same manner.

The reinforcing material 17 is preferably made of the same metal material as the metal ribbon (to facilitate welding and ensure sufficient welding strength), and its thickness t is also approximately equal to that of the metal ribbon. The width d and length l are also determined to be as small as possible within the range that ensures durable joint strength, approximately 2 to 6 mm and approximately 5 to 20 mm, respectively, to prevent an increase in heat capacity due to the reinforcing material 7. is desirable.

As shown in FIGS. 6 and 7, the seal belt 1
Portion 18 between upper and lower reinforcing members 17 of 6a and 16b
The seal belt 16 is in contact with the contact portions 1a ₂ and 1b ₂ of the first heat bar and the contact portions (i.e. roll surfaces) 4a ₁ and 4b ₁ of the first pressure roll.
a and 16b are transferred. Therefore, the width h of the portion 18
is set to be slightly larger than the width (ie, height) of the contact portions 1a ₂ , 1b ₂ ; 4a ₁ , 4b ₁ . Similarly, the width h of the portion 18 is the same as that of the second heat bar 2a,
2b, the width is set to be slightly larger than the width of the contact portion of the second pressure rolls 5a, 5b and the cooling bars 3a, 3b. Usually, the widths of these contact parts are equal to each other and equal to the width of the heat-sealed part 9a ₁ of the mouth end 9a (usually about 10 mm).

Note that in FIGS. 3, 6, and 7, the reinforcing members 17 of the seal belts 16a and 16b are facing each other, but this is an example of an extreme case.
Usually not facing each other.

According to the present invention, as described above, the seal belt 1
Since the surfaces of the joints 15a, 5b of the joints 15a, 16b that contact the mouth end 9a and the surfaces that contact the contact portions of the heat bar, pressure roll, and cooling bar are flat, there is no incomplete heat sealing based on the joints. This has the effect that there is no risk of this occurring.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an example of a conventional heat sealing device and the present invention. FIG. 2 is an enlarged plan view of the vicinity of the first pressure roll when a conventional sealing belt is used. FIG. 3 is a plan view showing an example of the heat sealing device of the present invention. FIG. 4 is a front view of the outer surface of the joint of the seal belt in FIG. 3, and FIG. 6 is a longitudinal cross-sectional view taken along line - in Fig. 3, and Fig. 7 is a main part taken along line - in Fig. 1 when the seal belt shown in Fig. 3 is used. It is an enlarged longitudinal cross-sectional view. 1a, 1b...first heat bar, 2a, 2b
...Second heat bar, 3a, 3b...Cooling bar, 4a, 4b...First pressure roll, 5a, 5
b...Second pressure roll, 9...Pouch, 16
a, 16b...Infinite circulation seal belt, 16a ₁ ,
16a ₂ ; 16b ₁ , 16b ₂ ... end, 17 ... reinforcing material, 18 ... portion between reinforcing materials.

Claims (1)

[Claims] 1 at least one pair of opposing heat bars, a pressure roll provided downstream of the heat bar, a cooling bar provided downstream of the pressure roll, and between each of the heat bar, the pressure roll, and the cooling bar, A pouch heat sealing apparatus comprising a pair of opposing infinitely circulating metal sealing belts passing in contact therewith, the endlessly circulating sealing belts abutting opposite ends of the metal ribbon to It is formed by joining reinforcing materials to both side edges of the inner surface, and the width of the part between the reinforcing materials is slightly larger than the width of the contact portion of each of the heat bar, the pressure roll, and the cooling bar. A pouch heat sheet device characterized by a large size.