JP2595453B2 - Push-pull control cable - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a push-pull control cable. More specifically, controls that reduce the clearance between the conduit and the inner cable without reducing the transmission efficiency and durability of the operating force in the pushing and pulling directions, thereby reducing backlash and improving buckling load About the cable. 2. Description of the Related Art A control cable generally comprises a flexible conduit and a single flexible inner cable inserted into the conduit. By performing a push-pull operation, a rotation operation, or a combination thereof, a driven device attached to the other end of the inner cable is remotely controlled. Of the control cables, the inner cable of the control cable dedicated to pulling operation is mainly made of flexibility, so that a cable obtained by twisting only metal strands without using a core is used. Since a compressive force acts on the inner cable of the pulling operation control cable, a buckling load is increased, and as shown in FIGS. What used the core metal 3 and wound many wires 5 around the core metal 3 is used. In a push / pull operation control cable, a clearance (in between a conduit and an inner cable is required to ensure smooth sliding of the inner cable having a higher rigidity than that of an inner cable dedicated to pulling. (Inner diameter of conduit)-(outer diameter of inner cable)). For example, in a conventional push-pull control cable, for a conduit having a liner having an inner diameter of 3.7 mm, a force transmission efficiency and durability that can withstand practical use cannot be obtained unless a clearance of 0.5 mm or more is provided. [0005] In the conventional push-pull control cable, the clearance is large, so that the backlash (that the driven side does not accurately follow the push-pull operation amount) becomes large and manual push-pull control cables are used. The play in the pulling operation is large, and the input operation is not accurately transmitted to the driven side, resulting in a poor operation feeling. Further, there is a problem that the buckling load is not sufficiently large because the clearance is large. That is, in the inner cable of the conventional structure, if the clearance is reduced, the power transmission efficiency and the like are reduced, so that the disadvantage that the backlash is large is inevitably accepted. An object of the present invention is to solve such a conventional problem and to provide a push-pull control cable which does not decrease the power transmission efficiency even if the clearance is reduced. A control cable according to the present invention will be described with reference to FIG. 1. According to the present invention, an inner cable 2, which is inserted into a conduit 1 and has good linearity, has a single cored bar. And a normally twisted strand 4 wound around the cored bar 3 so that the direction of the wire 5 appearing on the surface is substantially parallel to the longitudinal direction of the inner cable.
Swing control after winding
A cable between the inner cable and the conduit
Is 0.2 mm . The strand 4 refers to a strand of several strands 5 twisted. The normally twisted strand 4 is, for example, as shown in FIG. 2 in the direction in which the inner cable 2 is twisted (the winding of the strand 4). Direction (arrow A direction)) and strand 4
A strand whose direction of twist (the direction of winding the element wire 5 (direction of arrow B)) is opposite to each other. In this case, the strand 5 appears substantially parallel to the longitudinal direction of the inner cable 2. In the case of the rung twist in which the twist direction of the inner cable 2 and the twist direction of the strand 4 itself are the same direction, as shown in FIG. 11, the strand 5 intersects the longitudinal direction of the inner cable 2. As can be seen, such a Lang twist is not used in the present invention. The winding direction of the strand 4 around the core 3 may be Z twist as shown in FIG. 3 or S twist as shown in FIG. Conventionally, as an inner cable of a push-pull control cable, there is no known cable in which strands are formed by twisting strands, and the strands are wound in a normal twist around a cored bar. [0011] In the case of a general pulling rope, in the case of rung twist, the length of the wire appearing on the surface is long and the surface of the rope is smooth, so that the contact area is large and the friction is small. It is also known that the angle formed by the strand with the center axis of the rope is much larger than in the case of a normal twist, so that the resistance to bending is small and the flexibility is high.
In the case of ordinary twisting, the strands appearing on the rope surface are largely bent and have relatively many irregularities. As a result, it is known that the contact area is small, and the strand is locally liable to be painful, which tends to result in poor durability. As for the inner cable of the push-pull control cable, the fact that there was no cable having a normally twisted strand at all was based on the knowledge about the above-mentioned general rope as it was, and therefore, the conventional twisted cable was not used. It is presumed that the inner cable using the strand was not adopted. However, when the present inventors conducted experiments on the inner cable according to the present invention using a normally twisted strand and having undergone swaging, it was surprisingly found that the inner cable was inserted into a control cable conduit and used. Is
High transmission efficiency can be achieved even if the clearance is reduced,
The result showed that the durability was also excellent. Next, the control cable of the present invention will be described in detail with reference to examples. FIG. 1 is an explanatory view of the configuration of the control cable of the present invention, FIG. 2 is an explanatory view showing the types of twisting of the strands 4, and FIGS. 3 to 4 show the twisting direction of the inner cable 2 (ie, the winding direction of the strand 4). 5 and 6 are a cross-sectional view and a side view of the inner cable 2 according to the first embodiment, respectively.
7 to 9 are cross-sectional views of the inner cable 2 according to Examples 2 to 4, respectively. FIGS. 10 to 11 are cross-sectional views and side views of the inner cable of Comparative Example 1, and FIGS. 14 and 15 are a cross-sectional view and a side view of a conventional inner cable described as Comparative Example 3, respectively.
16 to 19 are explanatory diagrams of an apparatus for measuring the mechanical performance of the inner cable. As the core metal 3 in the present invention, a conventionally used metal core can be used without any particular limitation, but one having good linearity is preferable. As such a core metal 3, for example, a metal wire such as a steel wire, a stainless steel wire, an oil-tempered wire, a bluing wire, or a non-metal wire such as a ceramic wire or an FRP wire is suitable. The core metal 3 may be composed of only one core wire as shown in FIG. 5, or several core wires around one core wire 3a as shown in FIG. The core 3 may be formed by winding the element wire 3b. As the core wire 3a and the element wire 3b, any of those conventionally used can be adopted. As the strand 4, a conventionally used strand obtained by twisting a strand 5 can be used without any particular limitation. For example, a steel wire, a stainless steel wire, or a zinc or nickel plated one thereof is used. Can be The number of the wires 5 constituting the strand 4 is not particularly limited, and is usually used in the range of about 5 to 22 wires such as 7 wires, 12 wires, and 19 wires, but more wires 5 are used. You may. The strand 4 is wound around the cored bar 3 in a direction opposite to the twisting direction, and the inner cable 2 having the normally twisted strand 4 is formed. Strand 4
If the twisting direction and the winding direction are opposite to each other, Z twisting or S twisting may be used. And
After the strand 4 is wound, swaging is performed. The inner cable 2 obtained as described above is shown in FIG.
As shown in (1), it is inserted into the conduit 1 and assembled into one control cable. The conduit 1 has a liner 6 made of a synthetic resin having excellent self-lubricating properties and abrasion resistance formed therein. Examples of the synthetic resin include polytetrafluoroethylene, polybutylene terephthalate, polyacetal, and polyethylene. Next, the control cables according to the first to third embodiments configured as described above will be described in comparison with comparative examples 1 to 3. Example 1 (See FIGS. 5 and 6) One oil-tempered wire having a diameter of 1.6 mm was used as the cored bar 3, and seven strands of galvanized steel wire having a diameter of 0.35 mm were used as the strands 4. Using strands twisted together, seven strands 4 are wound around the core 3 at a pitch of 17.5 mm.
The inner cable 2 shown in FIGS. After swaging, the diameter of the inner cable 2 was 3.5 mm. Inner diameter molded of polytetrafluoroethylene as conduit 1
A liner having a 3.7 mm liner 6 was prepared, and silicone grease was applied around the inner cable 2 and inserted into the inside of the conduit 1. Example 2 (see FIG. 7) The inner cable 2 shown in FIG. 7 was formed in the same manner as in Example 1 except that the strand 4 was formed from 12 galvanized ropes 5 having a diameter of 0.27 mm. I got 3.5 diameter after swaging
mm. The conduit 1 is the same as in the first embodiment, and the liner 6
With an inner diameter of 3.7 mm was used. Example 3 (see FIG. 8) Six strands each having a diameter of 0.22 mm were wound around a 0.24 mm diameter core wire made of galvanized steel wire as strands 4 as a lower stranded wire. Example 1 except that the wire was configured by winding 12 wires as a top stranded wire
In the same manner as in the above, an inner cable 2 shown in FIG. 8 was obtained. The diameter after swaging was 3.5 mm. The conduit 1 was the same as that in Example 1, and the inner diameter of the liner 6 was 3.7 mm. Comparative Example 1 (See FIGS. 10 to 11 ) The inner cable 2 shown in FIGS. 10 to 11 was manufactured in the same manner as in Example 1 except that the strand 5 and the strand 4 were both twisted into a Z twist to form a Lang twist. I got The same conduit 1 as in Example 1 was used. COMPARATIVE EXAMPLE 2 (See FIGS. 12 and 13) The core 3 is a single oil-tempered wire having a diameter of 2.0 mm, and 12 strands 5 of 0.6 mm in diameter are S-stranded around the core 3 . The inner cable 2 shown in FIGS. The diameter of the inner cable 2 is 3.2 mm. The conduit 1 was the same as that in Example 1, and the inner diameter of the liner 6 was 3.7 mm. Comparative Example 3 (See FIGS. 14 and 15) The core 3 is a single oil-tempered wire having a diameter of 1.6 mm, and 15 strands 5a having a diameter of 0.35 mm are Z-twisted around the core 3. 14 and the inner wire 2 shown in FIGS. 14 to 15 was obtained by winding 16 strands 5b having a diameter of 0.5 mm around the outer periphery in the S twist direction. The inner cable 2 after swaging has a diameter of 3.2 mm. The conduit 1 is the same as in Example 1,
The inner diameter of the liner 6 was 3.7 mm. With respect to the control cables of Examples 1 to 3 and Comparative Examples 1 to 3, force transmission efficiency, no-load sliding resistance, backlash, buckling load, and cutting load were measured. The measurement of the force transmission efficiency, the no-load sliding resistance, and the backlash were performed using the measuring devices shown in FIGS. In this example, a control cable having a conduit 1 having a length of 1400 mm on a base 10 is bent by 180 ° at a radius R1 of 152.4 mm (6 inches) and further bent by 180 ° at a radius of R2 of 203.2 mm (8 inches) and fixed. The load 2 serving as a reference is connected to one end 2e of the inner cable 2 via pulleys 11, 12 and a lever 13, and a push-pull force measuring device is connected to the other end 2f. First, the force transmission efficiency was measured by measuring one end 2 of the inner cable 2.
6.8 kg of push / pull load W was applied to each of the e. F1 and tensile operation force F2 were measured.
As shown in FIG. 17, the applied load W was changed by a pulley 11 at the time of a pulling operation, and by a weight connected in a different direction by a lever 13 and a pulley 11 at the time of a pushing operation. The described data is the average value of the measured values obtained by performing three push and pull operations on each of five samples and measuring three times each. The force transmission efficiency η _W was determined by the formula: (load W / operating force F) × 100 (%). Table 1 shows the results. The no-load sliding resistance was measured by the apparatus shown in FIGS.
The other end 2e was pushed or pulled by the pushing / pulling force measuring instrument, and the pushing force and the pulling force were measured. After pushing and pulling each of the five samples about 10 times,
Table 1 shows the average value of the operating force measured each time. The backlash is measured by fixing the other end 2f of the inner cable 2 to the pulleys 11, 12 and the lever 13 in the same manner as described above in the apparatus shown in FIGS.
A 2 kgf pushing / pulling load was applied through the above, and the amount of movement at that time was measured. Each of the lengths L1 indicating the fixed position of the inner cable 2 is 20 mm, and the movement amount is obtained by measuring the reference distance L2 with a caliper. Table 1 shows the average values measured three times for each of the five samples. As shown in FIG. 18, the buckling load of the inner cable is measured according to the rod-guide pipe method generally used as a method for connecting the ends of the push-pull control cable. The inner cable 2 is inserted into a pipe 14 having a diameter of 1 mm, and one end 2e of the inner cable 2 is fixed by a chuck 15 and the other end 2f is fixed to a member 16 which is pierced by a rod. The pressing force was measured. The gripping margins C1 and C2 at both ends of the inner cable 2 are 15 mm and 20 mm, respectively, and the effective length L5 of the inner cable 2 is 75 mm.
mm. Table 1 shows the average values measured for the three samples. The cutting load is measured by gripping both ends of the inner cable 2 having a length of 350 mm with a margin of 50 mm (ie, an effective length of 250 mm) with a chuck of an Amsler testing machine and pulling the cable. The load was measured. Wires were previously wound around the grips at both ends of the inner cable and soldered to prevent slipping. The durability was measured using an apparatus shown in FIG. One end 2e of the inner cable 2 is held by a spring 17,
A double swing load F3 of 0 to 40 kgf was applied to the other end 2f, and the number of times until the inner cable 2 was cut due to bending fatigue was measured. In FIG. 19, the radius of curvature of the curved portion R3 is
The length of conduit 1 was 850 mm. [Table 1] As is clear from the results in Table 1, the control cable of the present invention has good force transmission efficiency and no load even though the clearance is reduced to about 1/2 or less as compared with the conventional control cable. Since the sliding resistance is reduced to about 1/2, it can be seen that the friction is small and the durability is high. In addition, the backlash has been greatly reduced due to the smaller clearance. Therefore, transmission of the operating force is ensured, and operability is improved. Moreover, the buckling load and the cutting load are also better than the conventional example. An outer diameter having a sectional shape shown in FIG.
A 3.5 mm inner cable was manufactured as in Example 4 and this was
The following data were obtained when the measurement was carried out in the same manner as described above with the sample inserted into a mm liner, that is, with a clearance of 0.2 mm. Force transmission efficiency Pushing force 74.7% Pulling force 78.2% No-load sliding resistance Pushing force 0.3 kg Pulling force 0.32 kg Backlash 1.7 mm Cutting load 1250 kgf Durability More than 1,000,000 times Clearance between inner cable and conduit It can be seen that, despite the reduction in The push-pull control cable of the present invention has a small clearance and therefore has a small backlash, so that there is little backlash during manual push-pull operation and a good feeling. In addition, there is an effect that the buckling load is improved as a secondary effect. Further, despite the small clearance, the force transmission efficiency is excellent, and the durability and the like are not reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration explanatory view of a control cable of the present invention. FIG. 2 is an explanatory diagram showing types of twists of a strand 4; FIG. 3 is an explanatory diagram showing a twisting direction of the inner cable 2. FIG. 4 is an explanatory diagram showing a twisting direction of the inner cable 2. FIG. 5 is a sectional view of the inner cable 2 according to the first embodiment. FIG. 6 is a side view of the inner cable 2 according to the first embodiment. FIG. 7 is a cross-sectional view of an inner cable 2 according to a second embodiment. FIG. 8 is a sectional view of an inner cable 2 according to a third embodiment. FIG. 9 is a cross-sectional view of an inner cable 2 according to a fourth embodiment. FIG. 10 is a cross-sectional view of the inner cable of Comparative Example 1. FIG. 11 is a side view of the inner cable of Comparative Example 1. FIG. 12 is a cross-sectional view of a conventional inner cable described as Comparative Example 2. FIG. 13 is a side view of a conventional inner cable described as Comparative Example 2. FIG. 14 is a cross-sectional view of a conventional inner cable described as Comparative Example 3. FIG. 15 is a side view of a conventional inner cable described as Comparative Example 3. FIG. 16 is an explanatory diagram of a measuring device. FIG. 17 is an explanatory diagram of a measuring device. FIG. 18 is an explanatory diagram of a measuring device. FIG. 19 is an explanatory diagram of a measuring device. [Description of Signs] 1 conduit 2 inner cable 3 core 4 strand 5 strand

Continuation of front page    (56) References Japanese Utility Model Application No. Sho 51-139194               No. 64755) and the specification attached to the application               Microfilm of the contents of the drawing               (JP, U)                 Japanese Utility Model Application No. 58-85377 (Japanese Utility Model Application No. 59-85377)               189924) and the specification attached to the application               Microfilm of the contents of the drawing               (JP, U)                 Japanese Utility Model Application No. 56-19113               131621) and the specification attached to the application               Microfilm of the contents of the drawing               (JP, U)                 JP-B 52-26727 (JP, B2)                 Jiko 48-16008 (JP, Y1)                 48-13769 (JP, Y1)                 Shoko 57-12740 (JP, Y2)

Claims (1)

(57) [Claims] 1. The inner cable to be inserted into the conduit is a single linear cored bar, and the direction of the wire appearing on the surface is substantially parallel to the longitudinal direction of the inner cable. A normally twisted strand wound around the core metal, and a swaging control cable which is subjected to swaging after winding the strand , wherein a clearance between the inner cable and the conduit is provided. 0.2mm
Characteristic control cable . 2. The control cable according to claim 1, wherein the strand is formed by twisting 5 to 22 strands. 3 Claims first claim of control cable, wherein the inner diameter of the conduit is 3.7 mm.