JPS5917233B2 - Wire rope and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wire rope used as a motion transmitting component in various devices such as printers.

In recent years, wire ropes have come into widespread use as motion transmitting parts for printers, XY plotters, various measuring instruments, copying machines, and the like.

By the way, this type of wire rope is generally formed by twisting several steel wires together to form a strand, which is then further Z-twisted or S-twisted.

When such a wire rope is used in a terminal device such as a printer, it is desirable that the wire rope satisfies the following conditions.

In other words, (1) it must have excellent flexibility so that it can be used by bending in any direction, and (2) it must have a spring constant that is small, since sufficient springiness is required even in areas where the tensile load is particularly small. (3) Sufficiently withstand tensile or bending stress caused by repeated loading over a long period of time and do not elongate, that is, have a long life; (4) Between each strand, between strands, and between pulley wires. One of the advantages is that there is no wear due to friction between the ropes, that is, it has excellent wear resistance.

However, in conventional wire ropes of this type, emphasis is placed on the flexibility described in (1) above, and the spring constant, lifespan, and abrasion resistance required for printers, etc. are neglected, and the results are never satisfactory. It wasn't.

In other words, conventional wire ropes are made from wire rods that have been formed through severe cold processing called wire drawing.
Since these wires are twisted together, the residual stress generated by drawing the wire decreases under the influence of the stress generated by repeated loads during subsequent use, causing the wire to soften and become easily elongated.

Another disadvantage is that the spring constant of conventional wire materials is small, and elongation increases due to wear due to friction between each wire, between strands, or between pulleys and wire ropes, which can also cause breakage. there were.

Especially in recent years, the speed of printers used as terminals in information equipment has gradually become faster, so when wire ropes like this are used as a material for conveying the movement of type, the characters may become distorted if the wire rope stretches or wears out. etc., resulting in a decline in printed product a.

For this reason, there has been a strong demand for the development of a wire rope that does not have such runners-up.

The present invention was made in response to such demands.
By forming the wire rope from stainless steel wire, forming an oxide film on its surface, and impregnating the entire wire with oil, we have created a wire rope with excellent flexibility, durability, and abrasion resistance. This is what we provide.

Furthermore, the present invention provides a method for manufacturing the wire rope, in which the spring constant is significantly improved by employing a step of forming an oxide film on the surface of the stainless steel wire by heat treatment.

The configuration etc. will be explained in detail below.

In the wire rope according to the present invention, first, stainless steel such as 18-8 series, 117-7P, and 17-4PH is used for the wire forming the rope.

This material has greater mechanical strength than other materials, and furthermore, as shown in FIG. 1, the springiness is greatly improved by heat treatment as described below.

These strands are then twisted together to form a strand, which is further twisted to form a wire rope. Heat treatment is performed in an atmosphere of 300 to 600° C. to form an oxide film on the surface.

This heat treatment greatly increases the spring constant of the wire rope compared to the untreated wire rope, as shown in FIG.

Generally, such heat treatment increases mechanical strength.
, it is often thought that the flexibility of the wire loaf itself decreases, but in the case of stainless steel, due to the presence of an oxide film formed on its surface, the resiliency constant increases as mentioned earlier. It also improves flexibility.

Furthermore, the oxide film formed on the surface of each wire by this heat treatment not only increases the spring constant as described above, but also has the effect of reducing the gaps between the wires and between the strands.

Furthermore, since countless minute pores are formed on the surface of this oxide film, oil, which will be described later, is effectively captured by these pores.

The wire rope with the oxide film formed on its surface is immersed in oil or coated with oil on its surface, thereby allowing oil to penetrate between the wires and between the strands.

By this oil impregnation treatment, oil as a lubricating oil is trapped in the recessed holes, so that wear caused by friction between wires and between strands is significantly improved.

The wire rope thus formed is further coated with a synthetic resin, if necessary.

That is, when the wire rope is used by being wound around a metal pulley, this coating prevents wear due to friction between the pulley and the wire rope and eliminates slippage.

Next, examples using the manufacturing method of the present invention will be described.

18-8 stainless steel wires with a wire diameter of 0.11 to 0.12 mm are twisted together in a twist configuration of 7 x 18, and the rope diameter is 1.
A wire rope of 6 mm is formed, and this is continuously heat-treated in an atmosphere at a temperature of 550°C while applying a tension of about 5 times the breaking force of the rope to form an oxide film, and then a commonly used lubricating oil is applied. The wire rope was dipped in oil to obtain a wire rope completely covered with a nylon braid.

The mechanical strength, spring constant, and life test results of this wire rope are as follows.

It can be seen that the spring constant has increased and the durability has also been significantly improved.

As explained above, according to the present invention, it is possible to obtain a wire rope that has greater mechanical strength and spring constant, and is superior in durability and abrasion resistance, without any loss in flexibility compared to conventional wire ropes. Can be done.

Furthermore, especially when the wire rope of the present invention is used as a motion transmitting part for terminal devices such as printers and various measuring instruments, which require increasingly higher reliability and higher speed, the effects are extremely significant.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the heat treatment temperature of the stainless steel wire used in the wire rope of the present invention and the spring limit value, and FIG.
The figure also shows the relationship between the heat treatment temperature of the wire rope and the spring constant.

Claims (1)

[Scope of Claims] 1. A wire rope characterized in that the entire wire rope is made of stainless steel wire on which an oxide film is formed by heat treatment and is impregnated with oil. 2. A method for producing a wire rope, which comprises twisting stainless steel wires together, subjecting them to heat treatment to form an oxide film on the surface of the stainless steel wires, and then subjecting them to oil impregnation treatment. 3. A method for producing a wire rope, which comprises subjecting stainless steel wire to heat treatment to form an oxide film on the surface of the stainless steel wire, and then twisting the stainless steel wire and subjecting the wire to oil impregnation treatment.