JPH048234Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention comprises a plurality of slats supported vertically at regular intervals, and a cord that hangs down from the head box through a lifting cord insertion hole provided in each slat. This invention relates to a lifting cord used in a horizontal blind of the type in which the slats are raised and lowered by winding up and lowering the lifting cord connected to the lower plate at the lower end.

[Advanced technology] As the above-mentioned type of horizontal brand slat lifting cord, one in which a plurality of threads are braided around a core material is generally used.

Such conventional lifting cords generally use polyester yarn, an example of which is shown in FIG. 21. This lifting cord 1 is made by braiding surface threads 3 around a core material 2, and in the illustrated example, four surface threads 3 are braided around the core material 2.

Threads used for such core materials and surface yarns include left-twisted yarn as shown in Figure 3 A, right-twisted yarn as shown in B, and non-twisted yarn as shown in C. In this case, as the core material 2, Fig. 3A,
Alternatively, the twisted yarn shown in B is used, and the surface yarn 3
As shown in FIG. 3C, untwisted yarn is used.

Such a lifting cord hangs down from the head box (not shown) of the blind through a lifting cord insertion hole provided in each slat, and is connected to the lower plate at the lower end, and can be rolled up and lowered. Then move the slats up and down. In FIG. 4, 1 is a lifting cord, 4 is a slat, 5 is a lifting cord insertion hole, and 6 is a ladder-shaped support cord that supports a plurality of slats vertically at regular intervals.

[Problems to be solved by the invention] In such a structure, when hoisting the lifting cord 1, the load of each slat is sequentially applied to the lifting cord 1, and finally the total weight of the slats is applied to the lifting cord 1. This requires high tensile strength and low elongation, but polyester yarns cannot provide sufficient strength and cannot be made into large-sized blinds. Alternatively, the lifting cord becomes thicker, and the lifting cord insertion hole in the slat needs to be enlarged, which has the disadvantage that the strength of the slat becomes weaker. Furthermore, when the slat is raised and lowered by winding up and lowering the lifting cord 1, the surface thread 3 rubs against the edge of the lifting cord insertion hole 5. Thread 3
As shown in Fig. 3C, untwisted yarn is used, which is wound spirally around the core material 2, and as shown in Fig. 5, the surface yarn 3 is aligned with the axis X of the lifting cord. - It is oblique to X at an angle θ. Consequently, when the slat is raised and lowered, the surface thread 3
When the thread rubs against the edge of the lifting cord insertion hole 5 of the slat, the fibers of the surface yarn come into diagonal contact with the edge of the lifting cord insertion hole of the slat, so the fibers of the surface yarn are turned over by the edge of the lifting cord insertion hole. Alternatively, there is a high possibility that it will be hooked, initially protrude from the surface in a loop shape, and eventually be worn out by repeated lifting and lowering operations.

As a result, there were problems such as the lifting cord breaking in a relatively short period of time due to the fraying of the surface braided yarn and the cutting of the core material due to the tensile force applied to the core material.

[Purpose of invention]

The purpose of the present invention is to eliminate the drawbacks of the conventional lifting cords as described above, to provide a lifting cord with high tensile strength and low elongation, and more preferably to reduce fraying of the surface braided yarn. To provide a lift cord for a blind that has a longer lifespan than conventional ones.

[Means for solving problems]

The present invention, as a means of solving the above-mentioned problems with lifting cords for blinds, includes a plurality of slats supported vertically at regular intervals, hangs down from the head box, and connects to the lower plate at the lower end of the slats. A lifting cord for horizontal blinds in which slats are raised and lowered by connected lifting cords, characterized in that a braided layer of polyester yarn is provided around a core material made of aromatic polyamide fiber yarn. More preferably, the knitting yarns in the above-mentioned braided layer are right-twisted yarns for the yarns that are braided in the left rotation, and left-handed yarns are used for the yarns that are braided in the right rotation. The present invention provides a lifting cord for a blind, which is characterized in that it is used.

Here, the aromatic polyamide fiber used as the core material has excellent characteristics such as high tensile strength and low elongation rate, and the present invention is based on the use of this fiber as the core material of the lifting cord. Therefore, the following advantages can be achieved as a lift cord for blinds.

(1) Since large tensile strength can be obtained, the cord can be prevented from breaking in a short period of time, and large-sized blinds can be manufactured.

(2) A thinner cord is required to obtain the same strength, so
In conjunction with this, the lifting cord insertion hole formed in the slat can be made smaller, thereby making it possible to manufacture a blind with excellent light-shielding properties and an excellent appearance.

(3) Generally, the brine has two lifting cords on the left and right, and the upper end of the cord is extended towards one end within the headbox, and the two lifting cords are tied together and downward from the end of the headbox. The left and right lifting cords have different lengths because the lifting operation cord is hung from the window and is pulled to raise and lower the blind. As a result, as the blind is used, the lifting cord stretches, causing an imbalance in the lengths of the left and right lifting cords of the blind, causing the entire blind to tilt left and right. However, by using the above-mentioned fibers as the core material of the lifting cord, the difference in elongation between the left and right cords is reduced, and it is possible to prevent the blind from tilting to the left or right.

(4) Furthermore, since the above-mentioned aromatic polyamide fiber has excellent heat resistance, it will not be adversely affected even if it is used in a place exposed to considerable high temperatures.

As mentioned above, the lifting cord for blinds according to the present invention can obtain an excellent lifting cord by using aromatic polyamide fiber yarn as a core material, but the disadvantage of this fiber yarn is that it has poor abrasion resistance. Therefore, there is a high possibility that the lifting cord will wear out while the blind is in use. In order to compensate for these drawbacks, the present invention provides a braided layer of polyester yarn around the core material. Furthermore, in this braided layer, the knitting yarns to be braided around the above-mentioned core material are right-twisted yarns for yarns that are braided by rotating counterclockwise with respect to the core material, and left-twisted yarns for yarns that are braided by rotating clockwise with respect to the core material. It is used.

As a result, as shown in FIG. 6, each fiber of all the surface yarns of the obtained lifting cord is almost parallel to the axis X-X of the lifting cord, and the lifting cord is made as shown in FIG. 4. When passed through the elevating cord insertion hole of the slat, each fiber of the elevating cord contacts the edge of the elevating cord insertion hole 5 in an almost perpendicular direction, and when the slat is moved up and down, the fibers of the surface yarn contact the edge of the elevating cord insertion hole of the slat. The possibility of the fibers being cut by being turned over by the paper is extremely reduced.

〔Example〕

FIG. 1 shows an embodiment of a lifting cord for a blind according to the present invention. In the figure, 1 is the core material, 3a, 3
b shows the surface threads braided around the core material.

As the core material 1, two 1500d aromatic polyamide fibers manufactured by DuPont were used. As the yarn for the surface braided layer, 16 500d polyester yarns made by Unitika were used. The manufacturing method of this lifting cord for blinds is as follows.
Apply tension to eliminate slack in the core material. Next, the surface polyester thread 500d, S twisted thread, Z twisted thread
Add 37.5g of tension to 16 strands and braid as above. On top of that, a coating of tetrafluoroethylene resin manufactured by Mitsui Fluorochemical Co., Ltd. was applied.

The quality of the product obtained by subjecting the lift cord for blinds manufactured as described above to inspection according to inspection standards was as follows.

(1) Shrinkage rate 1% or less (2) Elongation rate 0.5% or less (3) Tensile strength 50Kgf or more (4) Light resistance 120 hours, grade 4 or higher (5) Abrasion resistance 2000 times or more As described above, this invention By changing the twisting direction of the core material and the surface threads knitted around it, loop-shaped fluffing is prevented on the outer circumferential surface of the lifting cord, and the cord is also prevented from being cut. To provide a lifting cord for a blind which has an extremely long life compared to the previous one.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an example of a lifting cord for blinds according to the present invention, Fig. 2 is a side view showing an example of a conventional lifting cord for blinds, and Fig. 3 A, B, and C are for blinds. Figure 4 is a perspective view showing the relationship between the lifting cord and the slats of the blind, and Figures 5 and 6 are diagrams showing the three types of threads used to construct the lifting cord and the book. FIG. 3 is an enlarged view comparing and showing the structure of the invented lifting cord. 1... Lifting cord, 2... Core material, 3, 3a, 3
b... surface thread, 4... slat, 5... insertion hole,
6...Support code.

Claims (1)

[Claims for Utility Model Registration] (1) A slat system comprising a plurality of slats supported vertically at regular intervals, suspended from a head box, and connected to a lower plate at the lower end of the slats by a lifting cord. 1. A lifting cord for a horizontal blind, which lifts and lowers a horizontal blind, characterized in that a braided layer of polyester yarn is provided around a core material made of aromatic polyamide fiber. (2) The knitting yarn in the above braided layer is attached to the core material,
The lifting cord for a blind according to claim (1) of the utility model registration, characterized in that the threads to be braided in the left rotation are right-twisted yarns, and the threads to be braided in the right rotation are left-handed yarns. .