JPH072379B2 - Manufacturing method of heat-shrinkable sponge rubber tube - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a heat-shrinkable rubber tube for coating various pipes such as automobiles, heaters, various pipes and handles for the purpose of cushioning, heat insulation and heat retention .

[0002]

Conventionally, a suitable method for producing heat-shrinkable rubber tube was no <br/>. Conventionally, a simple rubber tube having no heat shrinkability was used and the tube was covered by force. The inner diameter of the rubber tube was slightly larger than the outer diameter of the tube to allow a margin .

In the market, there is a method in which two half-split cylinders having a hollow structure are combined, a rubber tube is stretched therein, and cold water is poured into the hollow section to mold the tube .

[0004]

The friction between rubber pipes is very large, and the coating operation requires a great deal of time and physical strength. To reduce friction, or to improve the slip detergent, or infeed to see expanded compressed air, Dari screwed, but have been made various devices is very hard work.

The coated rubber tube may be extremely dense and dense in the longitudinal direction to move after being coated, or a gap may be formed between the tubes to reduce the heat insulation effect, and wrinkles may be formed in the bent portion of the bent tube. It also spoils the beauty of the product. If there is a heat-shrinkable rubber tube, the above problems can be solved.
Until now, there was no suitable manufacturing method.

It is possible to manufacture using two half-split cylinders having a hollow structure, but the length is only about 5 m. In addition, the joint of the half-split cylinder remains as a vertical streak, which is not aesthetic. Also, we have to produce each one,
It is troublesome and not economical. Further, the length is limited by the length of the two half-split cylinders , and is about 5 m at best. Also,
Because it stretches at the internal pressure before it is heated uniformly,
Good quality due to heat-shrinkable rubber tube that causes uneven shrinkage
Absent. In particular, sponge-like rubber tubes have low thermal conductivity.
Has a strong tendency.

[0007]

The present invention is directed to unstretched rubber.
A feeding step of feeding the pipe while applying internal pressure with compressed air;
A preheating step of uniformly heating the unstretched rubber tube to 60 ° C to 100 ° C, preferably 65 ° C to 85 ° C , and further heating the unstretched rubber tube to 100 ° C to 160 ° C, preferably 120 ° C to 150 ° C. as a stretching step of heating and expanding, the regulation of the expansion of the stretched rubber tube and a forming step of the outer diameter cooler with regulating ring for the purpose of holding the to inscribed passes, stretched rubber tube with cold water from showering In conjunction with the fixing process of washing and cooling
The present invention relates to a method for producing a heat-shrinkable rubber tube , which comprises a series of continuous steps of a heat-shrinkable rubber tube take-off step.

[0008]

First, compressed air 2 is sent to the unstretched rubber tube 1 to apply an internal pressure. No stretching has occurred yet at this stage. Deliver while applying internal pressure.

[0009] Preferably 100 ° C. The unstretched rubber tube 1 from 60 ° C. is heated so as to be 85 ° C. from 65 ° C.. This is not
Until the material inside the stretched rubber tube 1 is raised to a uniform constant temperature, which is preheated to provide smoothly further heating stretching declined immediately.

The preheated unstretched rubber tube 1 is further treated with 100
℃ to 160 ℃, preferably 120 ℃ to 150 ℃
To heat. Since it is preheated, the temperature rises to the inside in a short time, so it is stretched uniformly. As a heat source, the far-infrared ceramic heater mounted circumferentially, hot-air generator, the steam has a high temperature wet heat body such as silicone, silicone
Oil is the most suitable. The unstretched rubber tube 1 expands by the internal pressure and stretches in the radial direction.

The expansion of the stretched rubber tube 3 must be regulated while maintaining a predetermined outer diameter dimension. Expanded rubber
When the tube 3 is inscribed in the restriction ring 4 with a cooler, the stretched rubber tube 3 is stretched and molded in a regulated shape.

[0012] The stretched rubber which has come out of the regulation ring 4 with a cooler.
The tube 3 is kept stretched on the surface. However, since the stretched rubber tube 3 has a high heat insulating property, it may contract if the inside thereof is not completely cooled, and the finished size may become smaller than a predetermined size. Therefore, cold water is sprayed from the shower ring 5 to stabilize the stretched state for both complete cooling and surface cleaning. This allows heat shrinkability
The finished dimensions of the rubber tube 6 are highly accurate.

Finally, the heat shrinkage is linked with the delivery speed.
The rubber tube 6 is removed. These two are operated at a fixed ratio of approximately 1: 1 and can be continuously produced. This allows unstretched
Since the tube 1 is stretched only in the radial direction, the stretching ratio in the radial direction can be increased accordingly. That is, the heat-shrinkable rubber tube 6 having a large shrinkage ratio in the radial direction can be obtained.
Therefore, the covering work becomes easy. Since the density in the radial direction is uniform, when heat treatment is applied, it shrinks uniformly in the radial direction. When the shrinkage rate was actually calculated, it was 3.
The numerical values of 5% and 50.0% in the radial direction were obtained. According to experiments, it was found that when the shrinkage ratio in the vertical direction is small, when the curved pipe is covered and shrunk, wrinkles are hardly formed on the surface and the finished appearance is beautiful.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to this embodiment.

In the figure, reference numeral 1 is fed from the winding frame 7 by the delivery roll 8 while receiving the internal pressure of the compressed air 2.
It is an unstretched rubber tube . Rubber tube is spongy and non-sponge
It doesn't matter which one.

Reference numeral 9 in the drawing denotes large and small guide rolls arranged at various places in order to smoothly transfer the rubber tube .

In the figure, 10 is a high temperature silicone oil 12
It is a preheating tank that stores. While dive該予thermal bath 10, non-rolled
The inside of the material of the rubber elongation rubber tube 1 is uniformly heated to 85 ° C.

Reference numeral 11 in the drawing is a heating ring for heating the temperature of the unstretched rubber tube 1 to 150 ° C. necessary and sufficient for stretching. Make sure that the temperature of the rubber tube 1 pulled up from the preheating tank 10 does not fall when exposed to the outside air.
A cover is provided integrally with the heating ring 11 to prevent the oil 12 from scattering. In order to improve heating efficiency, the heating ring 11 is provided in upper and lower two stages. Hot silicone oil 12 is sprayed from the heating ring 11.

Silicone heated by a heater (not shown)
The oil 12 circulates between the heating ring 11 and the preheating tank 10 . Since the temperature in the preheating tank 10 releases heat to the atmosphere, it is maintained at a slightly lower suitable temperature. Heating ring 1
1 and the temperature of the preheating tank 10 are controlled by the heater.
You can make clauses.

Reference numeral 4 in the drawing denotes a cooler-equipped restriction ring for restricting the high temperature stretched rubber tube 3 to a predetermined outer diameter and molding it to a finished size by cooling to some extent. The cooler regulating ring 4 has a hollow structure, and cold water 13 circulates inside. The expanded rubber tube 3 which expands is a restriction ring 4 with a cooler.
Inscribed in, cooling progresses while moving. The silicone oil 12 on the surface of the rubber tube 3 serves as a lubricant to smoothly pass through.

Reference numeral 5 in the drawing denotes a shower ring for directly spraying the cold water 13 onto the rubber tube 3 . The cover formed integrally with the shower ring 5 has a role of preventing the scattering of the cold water 13 and at the same time, guiding water into the drainage receiving ring 14 in which the stretched rubber tube 3 is inscribed.

The above-mentioned preheating tank 10, heating ring 11,
The restriction ring with cooler 4, the drainage receiving ring 14, and the shower ring 5 are arranged vertically. In each of the steps of stretching, molding and fixing, the influence of gravity was taken into consideration in order to achieve uniform stretching.

Reference numeral 15 in the drawing is a winder for pulling the heat-shrinkable rubber tube 6 . The operation is always performed at a constant ratio in association with the speed of the delivery roll 8. In this embodiment, 1: 1 or ± 1
It can be variably adjusted with an increase / decrease ratio of 0%. In this embodiment, the tape is wound as it is long, but it may be cut to a regular length by a cutting machine. The heat-shrinkable rubber tube 6 looks thin in the figure because there is no air inside.

[0024]

As described above, the heat absorption according to the present invention
The manufacturing method of the shrinkable rubber tube has the following unique effects.

First, since the inside of the unstretched rubber tube can be uniformly heated by the two-step process of preheating and heating , uniform stretching can be performed. That is, it is possible to manufacture a heat-shrinkable rubber tube having a good quality that uniformly shrinks.

Since the heat-shrinkable rubber tube can be continuously manufactured, the length is not limited, and a free tube can be manufactured.

Since the heat-shrinkable rubber tube can be manufactured without interrupting the operation, it is economically excellent.

Since it is cooled by the cold water of the cooling ring with the cooler and the shower ring, the inside of the rubber tube can be completely cooled, and the precision of the finished dimension is very high.

Since the draw ratio in the machine direction is small, the shrinkage ratio in the same direction is very small, and accordingly, the draw ratio in the radial direction can be made large and the shrinkage ratio in the same direction can be made large. Therefore, the covering work becomes very easy.

There are no vertical stripes on the surface, and it is very smooth and beautiful in appearance.

Since the shrinkage ratio in the longitudinal direction is small, wrinkles cannot be formed on the surface even when the curved pipe is covered and shrunk. The finished appearance is beautiful.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

[Explanation of symbols]

1 unstretched rubber tube 2 compressed air 3 stretched rubber tube 4 regulating ring with cooler 5 shower ring 6 heat-shrinkable rubber tube

Claims (1)

[Claims] 1. A I to non-stretching rubber tube and delivery step of paying out while the internal pressure was added with compressed air, 85 ° C. The unstretched rubber tube from the uniform 100 ° C. preferably 65 ° C. from 60 ° C. to the inside
Preheating process to heat so that the unstretched rubber tube is 100
℃ to 160 ℃, preferably 120 ℃ to 150 ℃
As a stretching step of heating and expanding, the regulation of the expansion of the stretched rubber tube and a forming step of the outer diameter cooler with regulating ring for the purpose of holding the to inscribed passes, stretched rubber tube with cold water from showering It is characterized by comprising a series of continuous steps of a fixing step of washing and cooling the resin and a drawing step of drawing the heat-shrinkable rubber tube in conjunction with the feeding step.
Manufacturing method of heat-shrinkable rubber tube .