JP4313877B2 - Push-pull control cable for automobile transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a push-pull control cable for an automobile transmission used in a vehicle or the like.
[0002]
[Prior art]
As a control cable for connecting a transmission and a shift lever of an automobile, a conduit formed by covering the outer periphery of a liner made of a resin pipe with a strand wound with a fine metal wire, and covering the outer periphery of the strand with a jacket, and a core wire And a push-pull control cable comprising a side wire composed of a number of steel wires wound around the outer periphery of the core wire at a predetermined winding pitch angle and combined with a wire slidably inserted into the liner. in use.
[0003]
[Problems to be solved by the invention]
The conventional push-pull control cable does not consider the relationship between the winding pitch angle of the steel wire constituting the side wire and the load efficiency, and the steel wire is mainly used from the viewpoint of preventing the spiral winding of the side wire from being unraveled. It was larger than 25 degrees and spirally wound at a winding pitch angle of 30 degrees ahead. The inventor has found that when the winding pitch angle is large, the contact area between the side line and the liner increases, the sliding resistance increases, and the load efficiency, which is the ratio of the output load to the input load, decreases. In addition, the sliding resistance increases when the contact area is large, mainly because the sliding surface of the liner wears, so that the contact area increases at an accelerated rate. Decrease in acceleration.
[0004]
If the load efficiency is low, the operating force increases, so the sensitivity quality deteriorates , the durability decreases, and the push-pull control cable needs to be replaced. In recent years , durable consumer goods such as automobiles are required to be improved in sensitivity quality and maintenance-free for a long time close to the product life.
An object of the present invention is to provide a push-pull control cable for an automobile transmission that has high load efficiency, excellent sensibility quality, and enables long-term maintenance-free operation.
[0005]
[Means for Solving the Problems]
The present invention comprises a conduit having a liner formed of a resin pipe, a core wire, and a side wire composed of a number of steel wires wound around the outer periphery of the core wire at a predetermined winding pitch angle. In a push-pull control cable for an automobile transmission combined with a wire slidably inserted in the steel wire, the winding pitch angle of the steel wire is set to 13 degrees or more and 25 degrees or less, and the diameter of the steel wire is set to 0. 0. 2mm or more, to 0.6mm or less, Lateral line, is configured by Nishimaki singlet steel wire on the outer periphery of the core wire 5μm or more, 20 [mu] m are subjected to galvanizing treatment follows, 200 ± 30 mm Newton load It is characterized in that a load efficiency of 70% or more can be ensured after a repeated endurance test of 1 million times with a stroke of .
Further, in the present invention, it is characterized in that the Material roughness was 0.2μm or less in Ra display.
[0006]
[Operation and effect of the invention]
In this invention, since the winding pitch angle of the steel wire is set to 13 degrees or more and 25 degrees or less in the present invention, the contact area between the side line and the liner is reduced, and sliding friction is reduced. For this reason, load efficiency becomes high, operation force reduces, and it is excellent in sensitivity quality and durability. Therefore, when the push / pull control cable for an automobile transmission according to the present invention is used for connecting an automobile transmission and a shift lever, the cable is practically not required to be replaced, and the labor and cost for maintenance can be reduced.
Further, wires, lateral line to 5μm or more, because it was subjected to the following galvanized 20 [mu] m, since the sliding friction is reduced, which contributes to reduce the operating force increases the loading efficiency. That is, it is possible to ensure a load efficiency of 70% or more after one million cycles of endurance tests with a stroke of ± 30 mm at a load of 200 Newtons.
[0007]
In addition, when the diameter of the steel wire is 0.2 mm or more and 0.6 mm or less, there are advantages such as satisfying rigidity and durability and ensuring flexibility in bending and routing. Also, the side tracks by forming a steel wire with Nishimaki singlet the outer periphery of the core wire, that Do advantageous from the viewpoint of allowing the cost while ensuring rigidity.
The conduit is usually formed by covering the outer periphery of a liner made of a resin pipe with a strand wound with a fine metal wire and covering the outer periphery of the strand with a jacket.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Figure 1 is an automobile transmission for push-pull control cable 1 (hereinafter, simply push-pull control cable hereinafter) of the present invention shows a, and connects the vehicle transmission and the gearshift lever (both not shown) . The push-pull control cable 1 includes a conduit 2 having a liner 21 made of a polybutylene terephthalate pipe, and side wires 33 formed by winding a large number of small-diameter steel wires 32 around the outer periphery of a core wire 31. The wire 3 is slidably inserted into the liner 21 with a predetermined gap.
[0009]
The conduit 2 includes a strand 22 formed by winding a steel wire group having a diameter of 0.83 mm around the outer periphery of the liner 21 and a waterproof jacket 23 covering the outer periphery of the strand 22. The liner 21 can also use a fluororesin, a polyolefin resin, or a polyether resin. The steel wires of the steel wire group constituting the strand 22 can have a diameter of 0.6 mm to 1.0 mm.
[0010]
As for the wire 3, a steel wire having a diameter of 1.4 mm is used for the core wire 31, and the steel wire 32 constituting the side wire 33 has a diameter of 0.2 mm or more and 0.6 mm or less, and a predetermined winding pitch around the outer periphery of the core wire 31 It is spirally wound at the angle α. The diameter of the steel wire 32 is desirably 0.2 mm or more in order to ensure rigidity and satisfy durability, and is practically 0.6 mm or less in order to ensure bending and routing.
[0011]
It is practical to use a steel wire having a diameter of 1.2 to 1.6 mm as the core wire 31 from the viewpoint of obtaining rigidity of pushing and pulling and keeping the wire size within a predetermined diameter. The side wire 33 is preferably a single layer (single) winding of the steel wire 32 from the viewpoint of ensuring rigidity and cost reduction, but may be a multilayer (multiple) winding.
[0012]
The steel wire 32 is galvanized on a bare metal, and each steel wire 32 is covered with a plating layer. The surface roughness of the plating layer is Ra: 0.06 μm. The base metal and liner 21 have a static friction coefficient of 0.32, whereas the galvanized layer and liner 21 have a static friction coefficient of 0.26. That is, the plating layer has an effect of smoothing the surface of the steel wire 32 and reducing sliding friction between the side wire 33 and the liner 21 when the wire 3 slides in the longitudinal direction in the liner 21. The surface roughness of the plating layer is practically acceptable if Ra: 0.2 μm or less.
[0013]
The plated layer 35 has an action of smoothing the surface of the steel wire 32 and reducing sliding friction between the side wire 33 and the liner 21 when the wire 3 slides in the liner 21 in the longitudinal direction. Therefore, the plated layer 35 may be facilities on the entire surface of the steel wire 32 before being wound around the core wire 31, as shown in FIG. 2, after being wound around the core wire 31, to the outside of the wire 3 it may be facilities only to the portion facing.
[0014]
The lower limit of the thickness of the plating layer 35 was determined as follows. With the experimental device shown in FIG. 3, the push-pull control cable 1 having a length of 50 cm and a stroke of ± 30 mm with a load of 200 Newton are 1 million times (corresponding to about 10 years of use in an automobile transmission) The results of repeated durability tests are shown in FIG. As the durability test products, seven products having a thickness t of the plating layer 35 of 4.5 μm or less and seven products having a thickness of 6.0 μm or more are used. In any case, the surface roughness of the plating layer 35 is Ra: 0.06 μm.
[0015]
As shown in FIGS. 4 and 5, the relationship between the thickness t of the plated layer 35 and the load efficiency is practical even after one million repeated tests when the thickness t is 5 μm or more as in the present invention. It is possible to secure a load efficiency of about 70% or more without any problem. For this reason, it is not necessary to replace the push-pull control cable 1 even after 1 million repetitive operations.
[0016]
On the other hand, if the thickness t of the plating layer 35 is smaller than 5 μm, the plating layer 35 partially disappears in the curved portion having a small curvature with a large amount of sliding wear, and the base metal 34 is exposed. For this reason, load efficiency falls to 60% or less, and replacement | exchange of the push-pull control cable 1 is needed. The upper limit of the thickness t of the plating layer 35 is set to 20 μm or less because the plating layer 35 thicker than 20 μm is not necessary in practice and increases the cost.
[0017]
The method of galvanization may be either electrogalvanization or hot dip galvanization, and the plating layer 35 may be Fe—Zn alloy plating or Sn—Zn alloy plating. Needless to say, load efficiency is improved when grease is interposed between the sliding surfaces of the side wires 33 and the liner 21.
[0018]
The steel wire 32 constituting the side wire 33 is uniformly applied to a bus bar having a diameter of 1.5 mm to 2 mm with a galvanization of 25 μm to 60 μm, and the plated bus bar is drawn and elongated to be manufactured to the above dimensions. . In this case, there is an advantage that the structure can be hardened by stretching and the surface of the plated layer can be smoothed, and the galvanized layer after the drawing is uniform and the durability against wear is improved.
The conditions for drawing the dies during the drawing process are as follows.
Number of passes: 19 (preferably 18-22)
Die angle: 17 degrees (possible in the range of 15-20 degrees)
[0019]
In this embodiment, as shown in FIG. 6, the steel wire 32 is wound with a winding pitch angle α of 15 degrees. FIG. 7 is a graph showing the relationship between the winding pitch angle α and the load efficiency, and FIG. 8 is a graph showing the relationship between the winding pitch angle α of the steel wire 32 and the contact area between the side line 33 and the liner 21. is there. If the winding pitch angle α is smaller than 13 degrees, a problem that the steel wire 32 is peeled off from the core wire 31 occurs. Further, it is found that as the winding pitch angle α increases, the contact area between the side line 33 and the liner 21 increases and the load efficiency decreases. Therefore, it is necessary that 13 degrees ≦ winding pitch angle α ≦ 25 degrees, and preferably 15 degrees ≦ winding pitch angle α ≦ 20 degrees.
[0020]
Using the test device shown in FIG. 3, the push-pull control cable 1 having a length of 50 cm is subjected to a reciprocating motion of ± 30 mm stroke at a load of 200 Newton 1 million times (corresponding to about 10 years of use in an automobile transmission). The results of repeated endurance tests are shown in FIG. In addition, the endurance test product includes three comparative products with a winding pitch angle α of the steel wire 32 of 27 degrees, 29 degrees, and 31 degrees, and 13 degrees, 15 degrees, 17 degrees, 19 degrees, 21 degrees, 23 degrees, and 25 degrees. Seven of the present invention products are used.
[0021]
As shown in FIG. 7, the relationship between the winding pitch angle α and the load efficiency of the steel wire 32 is practical even after 1 million repetition tests when the winding pitch angle α is 25 degrees or less as in the present invention. It is possible to secure a load efficiency of about 70% or more without any problem. For this reason, it is not necessary to replace the push-pull control cable 1 even after 1 million repetitive operations.
[0022]
On the other hand, when the winding pitch angle α is larger than 25 degrees, the liner 21 is worn in a curved portion having a small curvature with a large amount of sliding wear, the load efficiency is reduced to 60% or less, and the push-pull control cable 1 can be replaced. Necessary. Note that the winding pitch angle α of the steel wire 32 is preferably as small as possible. However, if the winding pitch angle α is smaller than 13 degrees, the state in which the steel wire 32 is wound around the core wire 31 cannot be maintained, and the side wires 33 are separated from the core wire 31. ≦ Limited to winding pitch angle α.
[0023]
As described above, when the steel wire 32 is subjected to surface treatment such as galvanization and the winding pitch angle α is set to 13 degrees or more and 25 degrees or less, the sliding resistance is greatly reduced due to a synergistic effect. Efficiency is dramatically improved.
[Brief description of the drawings]
FIG. 1 is a perspective view of a push / pull control cable for an automobile transmission .
Figure 2 is a expansion large cross-sectional view of the wire.
FIG. 3 is a side view of the durability test apparatus.
FIG. 4 is a graph showing load efficiency before an endurance test.
FIG. 5 is a graph showing load efficiency after an endurance test.
FIG. 6 is an enlarged side view of a wire.
FIG. 7 is a graph showing the relationship between the winding pitch angle α and the load efficiency.
FIG. 8 is a graph showing a relationship between a winding pitch angle α and a contact area.
[Explanation of symbols]
1 Automotive transmission push / pull control cable 2 Conduit 3 Wire 21 Liner 31 Core wire 32 Steel wire 33 Side wire 35 Plating layer α Winding pitch angle

Claims (2)

Consists of a conduit having a liner formed of a resin pipe, a core wire, and a side wire composed of a number of steel wires wound around the outer periphery of the core wire at a predetermined winding pitch angle, and is slidable within the liner In the push-pull control cable for automobile transmissions combined with the wire inserted in
The winding pitch angle of the steel wire is set to 13 degrees or more and 25 degrees or less, the diameter of the steel wire is set to 0.2 mm or more and 0.6 mm or less, and the side wire is formed on the outer circumference of the core wire. singlet to Nishimaki to configured 5μm or more, 20 [mu] m have been subjected to zinc plating below 200 after repetition durability test of one million times by the stroke of ± 30 mm in load Newtons, more than 70% of the load A push-pull control cable for automobile transmissions, which can ensure efficiency . The push-pull control cable for an automobile transmission according to claim 1,
Push-pull control cable for an automobile transmission, characterized in that the Material roughness was 0.2μm or less in Ra display.

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