JPS6311722B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method of manufacturing flat cables.

For example, in the manufacture of twisted flat cables, a plurality of twisted pairs Ct having alternating twist portions and flat portions are sandwiched between two tapes T, and they are heat-sealed using a forming roller R and then cooled naturally or air-cooled. However, during the above-mentioned cooling, due to the repulsion from the twisting of the core wire, each pair is untwisted from the state shown in FIG. 1A, as shown in FIG. 1B, and the cable C is twisted as shown in FIG. Part Tw
The total width of is decreased. In the flat part where the tape is still in a softened state, it may be dragged by this and the core wire pitch of the flat part F of the cable C may not be constant.

The reduction in the width of the twisted portion Tw mentioned above varies depending on the number of core wires, so even if the pitch of the grooves on the forming roll R is increased by a certain factor, the dimension after shrinking will be the regular dimension. It is difficult to do so.

The above-mentioned reduction in width upon cooling is caused by the fused tape shrinking itself when it cools and becomes individual, which sometimes makes it difficult to connect the one-touch connector.

Such shrinkage also occurred in the manufacture of cables in which conductors were arranged in parallel and plastic tape was extruded on both sides.

The present invention was made based on the above circumstances, and
To provide a flat cable manufacturing method that does not cause width fluctuations after manufacturing.

The invention will be explained in detail below with reference to the drawings. FIG. 3 shows a twisted flat cable manufacturing apparatus for carrying out the present invention. The core wire 1 is made into a twisted pair having alternating twist portions and flat portions via a rotating perforated plate 2, and is sent via a guide roller 3 to a gap between a pair of heat forming rollers 4. Two strips of PVC are placed in the gap between the heat forming rollers 4 so as to sandwich the rows of core wires 1 from above and below.
A film 5 is supplied, and the PVC film is heat-sealed across the rows of core wires 1 by heating and pressure bonding by rollers 4.

The belt-shaped PVC film and the array of core wires 1 that are heat-sealed by the heat forming roller 4 become a twisted flat cable 6, which is rapidly cooled and solidified by the water-cooled cooling roller 5'. Reference numeral 7 indicates a presser roller for pressing the twist flat cable 6 against the cooling roller 5'.

In the above device, each roller has the following shape. That is, as shown for the cooling roller 5' in FIG. 4, the roller 5' has a circumferential length equal to the sum of the length of the flat part and the length of the twisted part of the core wire 1, and For the circumferential surface with the same circumferential length, grooves 8 for inserting each core wire 1 of the flat part are provided as many as the number of single wires, and for the circumferential surface with the circumferential length equal to the length of the twisted part, one /2 number of grooves 9 and twice the groove width are provided.

The guide roller 3 and the pressure forming roller 4 are installed in a press-contact relationship by adjusting their angular positions so that the number of grooves equal to the number of core wires completely oppose each other when the rollers rotate. In addition, the cooling roller 5' is connected to the twist flat cable 6.
The angular position is adjusted so that the groove 8 is engaged with the circumferential surface of the flat part of the groove 8.

As described above, in the present invention, the flat cable immediately after being pressurized and heated is rapidly cooled and solidified by the cooling roller 5' having the grooves 8 and 9 for regulating the pitch, so that the twisting by untwisting the twisted part is prevented. There is no imbalance in the team. Therefore, the width of the twisted part of the cable as shown in Fig. 2 can be reduced.
The core wire pitch in the flat portion will not be disturbed.

FIG. 5 shows an example in which the present invention is applied to the manufacture of a simple flat cable having no twist portion. In this example, the rows of core wires 1 are formed by grooves 10a in the circumferential direction provided at intervals equal to the arrangement pitch of the core wires 1.
The PVC film 5 is fed together with two strips of PVC film 5 into the gap between a pair of heat-forming rollers 10 having the same diameter, and the PVC film 5 is sandwiched between the rows of core wires 1 and heat-sealed to form a flat cable 6'.

The flat cable 6' has circumferential grooves 11a provided at intervals equal to the core wire arrangement pitch, and is passed through a gap between a pair of water-cooled or air-cooled cooling rollers 11. During this passage, the flat cable is arranged so that the core wire arrangement pitch is set in one circumferential groove.
Since it is rapidly cooled and solidified under the conditions regulated by 1a, it will not be difficult to connect the one-touch connector due to a decrease in cable width or disorder of the core wire arrangement pitch after manufacturing.

[Brief explanation of the drawing]

Figure 1A is a cross-sectional view of the heat-forming roller part during the production of a twisted flat cable, Figure B is a cross-sectional view for explaining the reason why the width of the twisted part of the twisted flat cable is reduced, and Figure 2 is a cross-sectional view of the A plan view of the twist part, FIG. 3 is a schematic diagram of an embodiment of the present invention,
Figure 4A is a plan view of the heat forming roller, Figure 4B
5 is a sectional view thereof, and FIG. 5 is a schematic perspective view of another embodiment of the present invention. 1... Core wire, 5'... Cooling roller, 6... Twisted flat cable, 6'... Flat cable, 8, 9,... Groove.

Claims (1)

[Claims] 1. A flat cable immediately after being formed by a heat forming roller is brought into contact with a cooling roller having a circumferential groove formed at the core wire arrangement pitch, and the core wire arrangement pitch is regulated by the circumferential groove while being rapidly cooled. A flat cable manufacturing method characterized by: