JP2003004020A - Control cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pushing/pulling control cable which is capable of cable arranging of small curvature, and, is excellent in buckling strength and endurance fatigue limit. SOLUTION: The control cable is constituted of an outer cable, and, an inner cable which is movably in the axial direction and internally inserted inside the outer cable. The inner cable has a core wire, and, side wires which are twisted around the core wire in a prescribed direction and arranged, and, surface compressive residual stress of 500 MPa-800 MPa is imparted to at least one of the element wires constituting the core wire and the side wires.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to transmission of operating force,
For example, the present invention relates to a control cable used for transmitting an operation force input to a shift lever in an automobile to a transmission.

[0002]

2. Description of the Related Art A push-pull control cable constructed so that an inner cable moves axially in an outer cable is used, for example, as an operation cord for connecting a select lever and a transmission in an automobile or the like. That is, when each range such as parking (P), reverse (R), neutral (N), drive (D) is selected by the select lever, the inner cable is pushed and pulled in the outer cable in the axial direction according to the selection. Switch the transmission range by pushing and pulling the inner cable.

In such a push-pull control cable, since it is necessary to transmit the operating force even when the inner cable is pushed, it is necessary to thicken the core wire of the inner cable to increase the buckling strength. On the other hand, with the recent reduction in the location of the control cable (for example, in the case of the above-described transmission control cable for automobiles, the location of the control cable is reduced by making the engine room of the automobile smaller), the control cable has a curvature. It is necessary to install with a small radius (hereinafter referred to as small bend installation). However, when an inner cable with a thick core wire is routed in a small bend, there is a problem that the bending moment acting on the core wire is large and the core wire is fatigued and broken due to long-term use. Therefore, various proposals have been made in order to enable a small bending arrangement and to satisfy high buckling strength and durability (Japanese Patent Laid-Open No. 09-088934 (hereinafter, referred to as Prior Art 1) and Japanese Patent Laid-Open No. 2000). -1304
27 (hereinafter, referred to as prior art 2)). Prior art 1 discloses an inner cable in which six side wires are arranged around one core wire and coated with a synthetic resin. In this inner cable, since the synthetic resin layer is provided around the core wire and the side wire, it is prevented from swelling like a lantern when a compressive load acts on the core wire and the side wire. Therefore, the buckling strength can be improved without increasing the diameter of the core wire and / or the side wire, and the diameter of the core wire and the side wire is not increased, so that the durability can be improved. The above-mentioned conventional technique 2 discloses a core material made of a stranded metal wire having spiral irregularities on its surface, and an inner cable coated with a synthetic resin in a state where the irregularities appear on the core material. . Also in this inner cable, as in the case of the above-mentioned conventional technique 1, the synthetic resin layer is provided around the core material to suppress an increase in the diameter of the core wire, thereby improving the buckling strength and the durability.

[0004]

However, in both of the above-mentioned conventional techniques, the buckling strength of the inner cable is improved by coating it with a synthetic resin. Therefore, the mechanical properties of the resin change due to heat and the inner cable of the inner cable changes. It has a problem that mechanical properties change.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a control cable which satisfies sufficient buckling strength and durability and which can be routed in a small bend. .

[0006]

Means for Solving the Problems and Effects In order to solve the above problems, the invention according to claim 1 is composed of an outer cable and an inner cable inserted inside the outer cable so as to be axially movable. Push-pull control cable, the inner cable is a core wire,
And a side wire arranged around the core wire in a predetermined direction. A surface compressive residual stress of 550 MPa to 800 MPa is applied to each of the strands of the core wire and / or each of the strands of the side wire. In such a control cable, the surface compressive residual stress of 550 MPa to 800 MPa is applied to each of the strands of the core wire and / or each of the strands of the side wire. Therefore, by imparting the surface compressive residual stress, the durability can be improved until the wire diameters of the core wire and the side wire are large. Since the wire diameter is large, the second moment of area is also large, so that the buckling strength can be improved. Further, the buckling strength and durability of the inner cable can be improved without coating the resin layer, and the problem that the mechanical characteristics of the inner cable change due to heat does not occur.

In the control cable according to the present invention, a resin layer is not coated on the outer circumferences of the core wire and the side wires of the inner cable, and a resin liner is arranged on the inner circumference surface of the outer cable. It is preferable. In such a control cable, since the outer periphery of the core wire and the side wire of the inner cable is not coated with the resin layer, the inner cable can be thinned as much as the resin layer is not coated. It is possible to omit the step of coating the resin layer on. Further, even if the outer circumferences of the core wire and the side wires of the inner cable are not coated with a resin layer, the inner peripheral surface of the outer cable that comes into contact with the inner cable is made of resin, so that it has excellent slidability and the contacting portion is different. As it is a material, no sticking occurs due to contact.

In the control cable according to the first or second aspect, it is preferable that the thickest wire among the core wire and the side wire is provided with the surface compressive residual stress. The largest bending stress acts on the thickest wire rod among the core wire and the side wire, and the durability is the most required. Therefore, the problem of durability can be solved by applying the surface compressive residual stress to the thickest wire among the wires forming the inner cable.

In the control cable according to any one of claims 1 to 3, the diameter of the thickest wire material forming the inner cable may be 1.0 mm to 1.8 mm. In such a control cable, the diameter of the thickest wire constituting the inner cable is 1.0 mm to 1.
Since it is 8 mm, the inner cable has sufficient buckling strength, and a large operating force can be transmitted even when the inner cable is pushed.

In the control cable according to the first aspect, the surface compressive residual stress applied to the core wire or the side wire is preferably applied by shot peening treatment. When the surface compressive residual stress is applied by the shot peening treatment, the surface compressive residual stress can be continuously applied in a short time as compared with other treatments such as nitriding treatment.
In addition, the nitriding treatment is not preferable from the environmental aspect such that the scale of equipment becomes large and harmful substances are discharged. However, the shot peening process reduces the scale of equipment,
It is also an effective method because it is harmless to the environment. The shot peening process has a shot projection density of 40.
It is preferably applied under the condition of 300 Kg / m ² . When the shot projection density is in the above range, the surface compressive residual stress imparted by shot peening can be increased.

According to the present invention, the input device for inputting the operating force of the operator, the input / output device for transmitting the operating force of the operator, and one end of which is connected to the input device An operation force transmission device, the other end of which is connected to an output device and which transmits an operation force input to an input device to the output device, wherein the control cable is an outer cable and an inner cable. Is composed of an inner cable that is inserted so as to be movable in the axial direction. And the inner cable is a core wire,
And a side wire that is arranged around the core wire in a predetermined direction by twisting,
Or 550MPa-800MPa for each wire that constitutes the side wire
The surface compressive residual stress is applied, and the outer cable is routed under the condition that the minimum bending radius is 60 mm to 140 mm. In such an operation force transmission device, the element wire forming the core wire and / or the element wire forming the side wire has 5
Since the surface compressive residual stress of 50 MPa to 800 MPa is applied, it has sufficient durability. Therefore, since the installation can be performed under the condition that the minimum radius of curvature is 60 to 140 mm, the operating force transmission device can be made compact and can be installed in a small space. In this case, it is preferable that the diameter of the thickest wire rod is 1.0 mm to 1.8 mm among the wires forming the core wire and / or the wires forming the side wire. With such a configuration, the inner cable has sufficient buckling strength, so that the operating force can be reliably transmitted. Further, in the range where the diameter of the thickest wire material constituting the inner cable is 1.2 to 1.6 mm, the effect of reducing the minimum radius of curvature (70 mm to 120 mm) is great, and particularly in the vicinity of the core wire diameter of 1.4 mm.
The minimum radius of curvature (about 80 mm) can be dramatically reduced.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The control cable of the present invention is preferably manufactured as follows and can be used as follows. The control cable of the present invention can be suitably implemented in the form shown in FIG. That is, the control cable A includes an outer cable C and an inner cable B that is inserted in the outer cable C so as to be axially movable. The inner cable B may include a core wire 40 and a plurality of side wires 42 arranged on the outer circumference of the core wire 40. The core wire 40 is formed to have an appropriate length according to the length of the wiring route. The wire diameter of the core wire 40 is
It can be appropriately determined according to the magnitude of the force transmitted when the inner cable B is pushed (transmitting force), and preferably in the range of 1.0 mm to 1.8 mm. If it is less than 1.0 mm, the buckling strength will decrease if the wire diameter is smaller than 1.0 mm, and a large number of twisted structures are required to have stable buckling strength, which leads to an increase in the diameter of the inner cable. Is. Also, if it exceeds 1.8 mm, the bending moment acting on the core wire 40 at the time of small bending installation becomes too large. As the material of the core wire 40, various materials conventionally used as the core wire of the inner cable can be used, and for example, a hard steel wire, a stainless wire, an oil temper wire, a brewing wire or the like can be used. Surface compression residual stress is preferably applied to the core wire 40 within a range of 550 MPa to 800 MPa. If it is less than 550 MPa, sufficient durability cannot be obtained, and if it exceeds 800 MPa, the process for applying the surface compressive residual stress becomes complicated and the surface compressive residual stress cannot be applied by a simple method. Is.

The treatment for imparting the surface compressive residual stress to the core wire 40 is preferably shot peening treatment. This is because the shot peening treatment can give the surface compressive residual stress within the above range in a short time. This shot peening process, for example,
The method and conditions described below can be suitably used.
FIG. 2 is a diagram schematically showing a method according to an embodiment for subjecting the wire rod 6 (the wire rod used for the core wire 40 of the inner cable B) to the shot peening process. As shown in FIG. 2, in the method according to this embodiment, the wire rod 6 is continuously fed in the direction of the arrow by rotating the pair of rollers 2a and 2b provided at a predetermined interval. The wire rod 6 that is continuously fed includes a pair of rollers 2.
Shot particles 8 are projected from a nozzle 4 provided between a and 2b, and the shot particles 8 collide with the wire rod 6, whereby surface compressive residual stress is imparted. In the shot peening process, it is preferable that tension is applied to the wire 6 by using the rollers 2a and 2b as tension rollers. Accordingly, even if the shot particles 8 collide with the wire rod 6, the straightness of the wire rod 6 is maintained, and the wire rod 6 can be continuously subjected to the shot peening treatment. Wire rod 6
It is preferable to apply a tension of 10 N or more. Further, the hardness of the shot particles 8 projected from the nozzle 4 is about the same as the hardness of the wire rod 6, and the diameter is preferably 0.1 to 0.3 mm. This is because when the hardness of the shot particles 8 is smaller than that of the wire rod 6, or when the shot particles 8 are less than 0.1 mm, the load applied to the wire rod 6 is small and sufficient surface compressive residual stress cannot be given. This is because, if the hardness is made higher than that of the wire rod 6, or if the shot particles 8 are larger than 0.3 mm, the wire rod 6 is damaged and deformed by the shot particles 8 being projected. It is preferable that a plurality of nozzles 4 that project the shot particles 8 onto the wire 6 be provided as shown in FIG. This is because the surface compressive residual stress is uniformly applied to the surface of the wire 6. It is preferable to provide four or more nozzles 4 and project the shot particles 8 onto the wire rod 6 from four or more directions. Further, it is preferable that the nozzles 4 are arranged at equal intervals. Also, the coverage of the shot peening process is preferably maintained at 60% or more. This is because if the coverage is maintained at 60% or more, a constant surface compressive residual stress can be applied to all parts of the wire rod 6. Here, the coverage is a value for determining the shot peening working strength, and is obtained from the ratio of the sum of the projected scratch area of the shot material to the worked area. When the shot particles 8 are projected from a plurality of directions (for example, four directions), the shot particles 8 can be applied to most of the wire rod 6 and coverage can be increased. Also, shot grains 8
It is preferable to perform processing at a projection speed of 20 to 60 m / sec, and a shot projection density of 40 to 300 m / sec.
It is preferably kg / m ² . Projection speed is 20 per second
In the case of m or less or the projection density of 40 kg / m ² or less, sufficient surface compressive residual stress is not given, and the projection speed of 60 m or more per second or the projection density of 300 kg / m ²
This is because in the above case, the impact when the shot particles 8 collide is too large and the wire rod is damaged and deformed.

The inner cable B is the core wire 40 described above.
Has a plurality of lateral lines 42 disposed outside the. Lateral line 4
2 is preferably arranged so as to tightly cover the core wire 40 by twisting the periphery of the core wire 40 in a predetermined direction. Lateral line 4
As the twisting method of 2, for example, single twisting, multiple twisting, Z twisting, or the like can be adopted. The wire diameter of the side wire 42 can be appropriately designed according to the wire diameter of the core wire 40, and is, for example, 0.3 to
The thing of about 0.38 mm can be used conveniently. Lateral line 4
The number of 2 can be appropriately determined by those skilled in the art according to the wire diameter of the core wire 40 and the wire diameter of the side wire 42, and in the example shown in FIG.
Fifteen lateral lines 42 are arranged. The material of the lateral line 42 is
Similar to the core wire 40 described above, a hard steel wire, a stainless wire, an oil temper wire, a brewing wire, etc. which have been conventionally used can be adopted. In this case, similar to the core wire 40 described above, surface compressive residual stress may be applied by shot peening or the like. Further, as the material of the side wire 42, in addition to the above-mentioned metal element wire, an element wire of fiber reinforced resin reinforced with glass fiber, carbon fiber or the like may be used.

The outer cable C is a cylindrical member into which the inner cable B can be inserted, and the liner layer 4
6 and a shield layer 48 disposed outside the liner layer 46.
And the coating layer 50.
The liner layer 46 is preferably formed of a resin in order to reduce the sliding resistance with the inner cable B. For example, polytetrafluoroethylene, polybutylene terephthalate, polyethylene, polyamide, polyacetal, a fluororesin, or a material thereof is used. An elastomer or the like can be used. When the liner layer 46 is made of resin, usual additives such as an antioxidant, a heat stabilizer, a lubricant, a crystal nucleating agent, a UV inhibitor, a colorant and a flame retardant are added to the liner layer 46. May be. The shield layer 48 is
It is formed by twisting a steel wire on the outside of the resin liner 46 in a predetermined direction. The twisting method of this steel wire is single twist, double twist,
Conventionally used twisting methods such as Z twisting can be adopted. Further, a galvanized steel wire or the like can be used for this steel wire. The coating layer 50 may be made of polyethylene, polyamide, or the like. Coating layer 50
Also, as with the resin liner 46, additives such as an antioxidant, a heat stabilizer, a lubricant, a crystal nucleating agent, an anti-UV agent, a colorant, and a flame retardant may be added.

The control cable A according to one embodiment of the present invention has been described above in detail, but this is merely an example, and the present invention is implemented in various modified and improved forms based on the knowledge of those skilled in the art. can do. For example, for the inner cable of the control cable A, the configuration of the core wire, the number of side wires, the twisting method, and the like should be implemented in various forms so as to satisfy the buckling strength, durability, etc. required according to the purpose. You can Other structures of the inner cable are shown in Figs.
Shown in. The inner cable G shown in FIG.
Are twisted together to form one side wire 102, and the side wire 102 is further twisted around the core wire 100. Specifically, one core wire 100 is provided with a (1 + 6) × 7 structure in which seven side wires 102 obtained by twisting seven thin wires 101 are twisted together. In such a case, it is preferable that the thickest core wire 100 of the wire materials forming the inner cable G is subjected to the shot peening process described above. The inner cable H shown in FIG. 4 has a plurality of (six) wire members 103 around the wire member 105.
Are twisted together to form one core wire 104, and 18 side wires 106 are twisted around the core wire 104. In this inner cable H, the core wire 104
The wire diameter of the wire rod 103 and the wire rod 105 constituting the wire is larger than that of the side wire 106. Therefore, these wire rods 103,
It is preferable that the shot peening process described above is performed on each of 105. Inner wire I shown in FIG.
The core wire 110 includes seven wire rods 1 as in FIG. 4 described above.
07 are twisted together, and eight side wires 108 are twisted and arranged outside the core wire 110. In this inner cable I, the side wire 108 has a larger wire diameter than the wire material 107 that constitutes the core wire 110. In such a case, it is preferable to perform the above-mentioned shot peening process on the side wire 108 having a large wire diameter.

[0017]

EXAMPLES Next, examples of the control cable according to the present invention will be described. As the control cable according to the example, the control cable A having the cross-sectional shape shown in FIG. 1 described above was manufactured. The core wire 40 of the inner cable B is made of hard steel wire (SWRH-67AorB).
~ 82AorB), cold-worked, and then oil tempered carbon steel oil tempered wire type B (hereinafter SW)
OB) was used. The diameter of the core wire 40 is 1.6 mm
And As the side wire 42, 15 strands of wire (SWRH62A) having a diameter of 0.38 mm were used as a single strand. The resin liner 46 of the outer cable C uses a polyamide liner, and the shield layer 48 uses a single strand of 18 steel wires (SWRH62A) with a diameter of 0.83 mm.
Polyamide resin was used for the coating layer. Regarding the control cable A having the above configuration, the core wire 40 is subjected to shot peening treatment under various conditions, and the relationship between each condition of the shot peening treatment and the surface compressive residual stress applied to the core wire 40 and the core wire 40 are applied. The relationship between the surface compressive residual stress and the endurance fatigue limit (MPa) was investigated. Further, the relationship between the core wire diameter and the minimum radius of curvature when the core wire 40 of the inner cable B having the structure of FIG.

FIG. 6 shows the relationship between the grain size of the shot grains and the surface compressive residual stress applied to the core wire 40. The core wire 40
Shot peening treatment was performed at a shot speed of 40 m / s and a shot density of 100 Kg / m ² . As is apparent from FIG. 6, the shot grains having a grain size of 0.
When it is smaller than 10 mm, the surface compressive residual stress applied to the core wire 40 becomes low, and the grain size of shot particles is 0.
The surface compressive residual stress was low even when it became larger than 30 mm. In particular, even if the grain size of the shot grains exceeds 0.30 mm, the surface compressive residual stress imparted does not increase.
It was about 0 MPa. As a result, in order to increase the surface compressive residual stress, the shot grain size should be 0.10 mm.
It has been found that it is preferable to set it in the range of 0.30 mm. FIG. 7 shows the relationship between the projection density and the surface compressive residual stress applied to the core wire 40. The shot speed of the shot particles on the core wire 40 was 40 m / s, and the particle size of the shot particles was 0.
Shot peening treatment was performed at 30 mm. As is clear from FIG. 7, when the projection density is lower than 40 Kg / m ^{2, the} surface compressive residual stress applied to the core wire 40 is 500.
When the projection density exceeds 300 Kg / m ² , the surface compressive residual stress applied to the core wire 40 is 50 MPa.
It was as low as 0 MPa. Thereby, in order to increase the surface compressive residual stress, the projection density is 40 Kg / m ² ~
It has been found that the range of 300 Kg / m ² is preferable.

Next, the endurance fatigue limit was measured by changing the magnitude of the surface compressive residual stress applied to the core wire 40. The measurement result is shown in FIG. The measurement of the endurance fatigue limit was performed by the pulley endurance machine shown in FIG. In FIG. 13, a connecting portion 6 for holding the inner cable B is provided at one end of the spring 64.
3 is attached. The other end of the spring 64 is attached to a wall surface (not shown) as a fixed end. The inner cable B whose one end is held by the connecting portion 63 is
It is pressed by the guide roller 60 and is in close contact with the pulley 65 having a radius of curvature R. The other end of the inner cable B is held by the holding portion 67. Then, the holder 67 is shown in FIG.
The inner cable B was oscillated by applying a one-sided repeated load F in the leftward direction of the arrow 3 and the maximum value of the test stress that cleared the number of times of endurance of 2 million times was defined as the endurance fatigue limit. As is clear from FIG. 8, the endurance fatigue limit drastically changes at the surface compression residual stress of 550 MPa, and when the surface compression residual stress becomes lower than 550 MPa, the endurance fatigue limit becomes 500.
When the pressure exceeds about 550 MPa, the endurance fatigue limit exceeds 650 MPa. As a result, it was found that the endurance fatigue limit sharply improved when the surface compression residual stress was 550 MPa. FIG. 9 shows the relationship between endurance fatigue limit and coverage. As is clear from FIG. 9, the endurance fatigue limit was as low as about 500 MPa in the range where the coverage was lower than 60%, and the endurance fatigue limit exceeded 600 MPa when the coverage was 60% or more.

Next, the results of evaluation of durability and buckling strength during small-bend installation will be described. First, a durability test method and a buckling strength measuring method will be described. At first,
A durability test method will be described with reference to FIG. In the durability test, as shown in FIG. 10, first, both ends of the outer cable C were fixed to a mounting base 80, and a curved pipe portion 78 was formed in the middle thereof to bend the outer cable C at 90 degrees. Next, the inner cable B was inserted into the outer cable 78 fixed to the mount 80, and the spring 82 was connected to one end thereof. Then, a double swinging load F1 was applied to the other end of the inner cable B, and the number of times until the inner cable B was cut due to bending fatigue was measured.
In addition, here, in order to evaluate the durability at the time of small bend installation, the radius of curvature R of the curved pipe portion 78 is variously changed, and the minimum radius of curvature that is not cut even if the repeated load F1 is applied 1 million times. R (hereinafter, simply referred to as minimum bending R) was used as the evaluation value. Next, FIG. 11 shows the method for measuring the buckling strength.
Will be described with reference to. As shown in FIG. 11, the inner diameter is 5 mm
A chuck 90 holds one end of the inner cable B inside the pipe 86. The metal fitting 92 provided at one end of the control cable A is fixed to the pipe 86. The inner cable B has a predetermined length L from the metal fitting 92.
Only (L = 40 mm in this experiment) was exposed. To the other end of the control cable A, a rod member 91 that is guided by the outer cable C and moves back and forth in the axial direction is connected. Then, by gradually pushing in the rod member 91, the load F2 acting on the inner cable B is measured,
The maximum load until the load F2 first fell significantly was recorded as the buckling strength.

Minimum bend R measured by the method described above
Table 1 shows the results of buckling strength. In Table 1, in Example 1, the inner cable B was connected to the core wire 40 (wire diameter φ1.6
mm) and 15 side wires 42 (wire diameter φ0.38 mm), and a core wire 40 having a surface compressive residual stress of 780 MPa was used. The inner cable B having the same structure as that of the first embodiment is used for the first comparative example, except that the core wire 40 is not subjected to the shot peening treatment and the surface compressive residual stress is 9
The thing of 3 MPa was used. In the second embodiment, the inner cable B is connected to the core wire 40 (wire diameter φ1.4 mm) and
The core wire 40 was composed of six side wires 42 (wire diameter φ0.30 mm), and a surface compressive residual stress of 780 MPa was applied to the core wire 40. In Comparative Example 2, the inner cable B having the same structure as in Example 2 was used, and the core wire 40 was not subjected to shot peening treatment and had a surface compression residual stress of 93 MPa.

[0022]

[Table 1]

As shown in Table 1, the control cables according to Example 1 and Example 2 in which the surface compressive residual stress of 780 MPa is applied to the core wire 40 are the smallest as compared with those of Comparative Example 1 and Comparative Example 2, respectively. It was confirmed that the bending R was small. Further, in both Example 1 and Example 2, no reduction in buckling strength due to application of surface compressive residual stress to the core wire 40 was confirmed, and both had the same buckling strength as Comparative Example 1 and Comparative Example 2. It was confirmed to be prepared.

Next, FIG. 14 shows the relationship between the core wire diameter and the minimum bend R when the core wire 40 of the inner cable B having the structure shown in FIG. 1 is shot peened. Figure 1
As shown in 4, when the core wire diameter is 1.0 mm or more, the minimum bending R can be reduced by performing shot peening treatment. In particular, the core wire diameter is 1.2 mm
It can be confirmed that the improvement rate of the minimum bend R is high in the range of 1.6 mm, and the minimum bend R can be dramatically improved in the vicinity of 1.4 mm. Also, the core wire diameter is 1.0 mm
It was also confirmed that if the ratio is less than the above, the effect on the minimum bending radius R is small.

As is clear from the above description, by applying the surface compressive residual stress of 550 MPa or more to the core wire of the inner cable, it was possible to dramatically improve the endurance fatigue limit. In addition, by appropriately adjusting the conditions of the shot peening treatment, the surface compression residual stress of 550 MPa to 800 MPa could be applied to the core wire only by the shot peening treatment. Therefore, it becomes possible to continuously apply the surface compressive residual stress to the core wire (steel element wire that is the material of the core wire) by the shot peening treatment as shown in FIG. 2, and to easily manufacture the core wire of the inner cable. You can

Further, as is clear from the description of the above-described first and second embodiments, the control cable according to the present embodiment has improved durability by imparting surface compressive residual stress to the core wire. The minimum bending R (durability; minimum radius of curvature that satisfies 1,000,000 cycles) can be made smaller than that of the conventional one. In particular, an operation force transmission device that requires safety (for example, a transmission device of an automobile)
When using a control cable for the
Clearing ten thousand times is an essential condition. Therefore,
According to the control cable of the present embodiment, it is possible to perform small-bend routing for a device that requires safety.
Further, in the control cable of this example, the buckling strength was maintained at the same level as that without the surface compressive residual stress even when the surface compressive residual stress was applied. In particular, the inner cable does not have improved buckling strength due to the coating of the resin material, unlike the prior art described above, so the buckling strength does not change due to temperature change due to heat. In addition, since the inner cable is not coated with the resin material, the diameter of the inner cable does not increase, and the space of the distribution cable can be made compact. Also, the core wire diameter is 1.0 m
When the length is m or more, the minimum bend R can be reduced by the shot peening process, so that a small bend routing with a radius of curvature which has been impossible in the past can be performed.

An example of an operating force transmission device which requires strict durability (duty count: 1 million times) will be briefly described with reference to FIG. FIG. 12 is a side view of a cart vehicle shift lever device using a control cable. As shown in FIG. 12, the vehicle shift lever device 20
Is the center boss 17 on the back of the steering wheel 10.
The shift lever 21 is swingably attached to the. One end of a control cable 22 is attached to the shift lever 21. Specifically, the outer cable of the control cable 22 is held by a cable holder 26 attached to a bracket 25 extending from the center boss 17, and the tip of the inner cable is guided by the cable holder 26 and is attached to one end of a rod 29a that moves back and forth. Connected. The other end of the rod 29a is connected to the shift lever 21, and when the shift lever 21 swings, the rod 29a moves back and forth. The position of the grip portion 21a of the shift lever 21 is set by the driver who operates the steering wheel 10 in the normal wheel portion 10a.
It is a position corresponding to the position where the hand is put on a, and is a position where the hand can reach the grip portion 21a if the finger is extended in that state. A change lever 24 on the transmission 19 side is connected to the other end of the control cable 22.
Specifically, the outer cable of the control cable 22 is held by a cable holder 28 attached to the vehicle body mount portion 27, and the tip of the inner cable is guided by the cable holder 28 and is moved forward and backward by a rod 29.
It is connected to one end of b. A change lever 24 is connected to the other end of the rod 29b via a ball joint 23, and the change lever 24 swings when the rod 29b moves back and forth. Then, the shift lever 21
The control cable 22 connecting the side of the transmission 19 to the side of the transmission 19 is routed by appropriately restraining the intermediate portion thereof.

In the above-described device, when shifting up, the right grip portion 21a of the shift lever 21 is swung so as to approach the wheel portion 10a. When the shift lever 21 swings, the rod 29a makes a stroke movement in the direction in which it projects from the cable holder 26, whereby the rod 29b makes a stroke movement in the direction accommodated in the cable holder 28. As a result, the transmission 19 sequentially shifts up. Also, when shifting down, the grip portion 21a on the left side of the shift lever 21
Is swung so as to approach the wheel portion 10a. When the shift lever 21 swings, the rod 29a strokes in the direction of being housed in the cable holder 26, which causes the rod 29b to move in the direction of protruding from the cable holder 28, contrary to the case of shifting up. As a result, the transmission 19 is downshifted in sequence.

As is apparent from the above description, in the above transmission, the control cable 22 (specifically,
Push and pull the inner cable) to shift lever 2
The operation No. 1 is transmitted to the transmission 19, and upshifting and downshifting are performed. Therefore, when the control cable according to the present embodiment is used as the control cable 22 of the above device, the control cable has sufficient buckling strength, so that the operation of the shift lever 21 is reliably transmitted to the transmission 19 and a reliable shift up operation is achieved.・ You can shift down. In addition, the control cable of the present embodiment has improved durability, so that it can be routed in a small bend, and since its outer diameter is not large, it can be installed in a narrow space, and the installation location of the transmission 19 is small. The degree of freedom of can be expanded.

Although the above-described example is an example in which the control cable according to the present invention is used in the transmission for a cart vehicle, the application example of the control cable according to the present invention is not limited to such an example. For example, the invention can be applied to a transmission (automatic device, manual transmission device) of a general private automobile.

[Brief description of drawings]

FIG. 1 is a sectional view of a control cable according to an embodiment of the present invention.

FIG. 2 is a perspective view schematically showing shot peening processing.

FIG. 3 is a sectional view of an inner cable according to another embodiment of the present invention.

FIG. 4 is a sectional view of an inner cable according to another embodiment of the present invention.

FIG. 5 is a cross-sectional view of an inner cable according to another embodiment of the present invention.

FIG. 6 is a graph showing the relationship between the diameter of shot grains and the surface compressive residual stress.

FIG. 7 is a graph showing the relationship between shot projection density and surface compressive residual stress.

FIG. 8 is a graph showing the relationship between surface compressive residual stress and endurance fatigue limit.

FIG. 9 is a graph showing the relationship between coverage and endurance fatigue limit.

FIG. 10 is a diagram schematically showing an apparatus for testing durability during small-bend installation.

FIG. 11 is a diagram schematically showing an apparatus for performing a buckling strength test.

FIG. 12 is a side view of a cart vehicle shift lever device in which the control cable according to the present invention can be preferably used.

FIG. 13 is a diagram schematically showing an apparatus for measuring endurance fatigue limit.

FIG. 14 is a graph showing the relationship between the core wire diameter and the minimum radius of curvature.

[Explanation of symbols]

A .. Control cable B .. Inner cable C .. Outer cable 2 ··· Tension roller 4 ... Nozzle 6 ·· Wire 8 ... Shot grains 40 ・ ・ Core wire 42 ・ ・ Side line 46 .. Resin liner 48..Shield layer ..Coating layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masami Wakita             68 Kamishiota, Narumi-cho, Midori-ku, Nagoya-shi, Aichi               Chuojo Co., Ltd. F term (reference) 3J032 AB33 AB40 BA01 BA06 BB04

Claims (7)

[Claims] 1. A push-pull control cable comprising an outer cable and an inner cable inserted inside the outer cable so as to be movable in the axial direction, wherein the inner cable has a core wire and a predetermined circumference around the core wire. And a side wire that is arranged in a twisted manner in the direction of, and a surface compressive residual stress of 550 MPa to 800 MPa is applied to each of the wires that form the core wire and / or each wire that forms the side wire. Control cable to do. 2. The core wire and side wires of the inner cable are not coated with a resin layer on the outer periphery thereof, and a resin liner is arranged on the inner peripheral surface of the outer cable. The control cable shown. 3. The thickest wire rod among the core wire and the side wire,
The control cable according to claim 1 or 2, wherein a surface compressive residual stress is applied. 4. The control cable according to claim 1, wherein the diameter of the thickest wire material forming the inner cable is 1.0 mm to 1.8 mm. 5. The control cable according to claim 1, wherein the surface compressive residual stress applied to the core wire or the side wire is applied by shot peening treatment. 6. The control cable according to claim 5, wherein the shot peening treatment is performed under the condition that the shot projection density is 40 to 300 kg / m ² . 7. An input device for inputting an operating force of an operator, an output device for transmitting the operating force of the operator, one end of which is connected to the input device and the other end of which is connected to the output device, In an operation force transmission device including a control cable for transmitting an operation force input to an input device to an output device, the control cable is an outer cable and an inner cable inserted inside the outer cable so as to be axially movable. The inner cable is composed of a core wire and a side wire twisted around the core wire in a predetermined direction, and each of the wires and / or the side wires forming the core wire is formed. A surface compressive residual stress of 550 MPa to 800 MPa is applied to the wire, and the outer cable is routed under the condition that the minimum radius of curvature is 60 mm to 140 mm. Operating force transmitting apparatus characterized by there.