JP5091438B2 - Inner cable and push-pull control cable using it - Google Patents

Description

  The present invention relates to an inner cable and a push-pull control cable using the inner cable. More specifically, the present invention relates to an inner cable and a push-pull control cable used for connecting an automatic transmission and a shift lever of an automobile to a so-called AT cable or MT cable.

JP 2003-287018 A JP 2004-263818 A JP 2004-19732 A

  Patent Document 1 discloses a push-pull control cable in which an inner cable 100 including a core wire 101 and side wires 102 and 103 spirally wound around the core wire is inserted into an outer casing 104 as shown in FIG. 105 is disclosed. The side lines 102 and 103 are composed of a large-diameter main side line 102 and a small-diameter sub-side line 103, which are alternately arranged. In Patent Document 1, an inner cable having high load efficiency and high buckling load is obtained by appropriately selecting the ratio of the diameters of the core wire 101, the main side wire 102, and the sub side wire 103 in the inner cable 100. It is supposed to be done. Patent Document 2 also discloses a similar inner cable.

  In Patent Document 3, a core composed of a core wire and side strands (side wires) of the same diameter twisted around the core wire, and a ridge that covers the core and extends straight in the axial direction on the outer periphery thereof. An inner cable composed of a plurality of synthetic resin outer layers provided at equal intervals and a push-pull control cable using the inner cable are disclosed. This inner cable can reduce the bending radius, has high load efficiency, low sliding resistance, and low backlash.

  The inner cable 100 of Patent Document 1 has a high buckling load and a minimum bending radius. If the wire diameter is reduced in an attempt to reduce the bending radius, the buckling load decreases. Furthermore, since this inner cable 100 spirally winds around the core wire 101 two types of wire materials having different wire diameters of the main side wire 102 and the sub-side wire 103, the spiral winding process is complicated. Furthermore, since the space ratio is high, backlash is large. The inner cable of Patent Document 2 has a similar tendency.

  On the other hand, since the inner cable of Patent Document 3 has a small minimum bending radius and the core wire and the side strands have substantially the same diameter, the twisting process (spiral winding process) is easy. However, since an outer layer made of a synthetic resin is provided, the material cost of the outer layer and the cost of extrusion molding are high. Moreover, since there is an outer layer of synthetic resin coating, backlash is large.

  An object of the present invention is to provide an inner cable and a push-pull control cable that have higher load efficiency than conventional inner cables, are easy to manufacture, are low in manufacturing cost, have a minimum bend radius, and have low backlash. .

Inner cables for the push-pull control cable of the present invention comprises a substantially circular section core wire, a plurality of lateral line twisted together around the core wire, the side wire is wire of modified cross-section consisting of a single wire the Ri processed torsion beam der twist in the same direction, respectively, wherein a part of the curvature portion of the modified cross-section, twist direction of the lateral line is a spiral direction opposite to the direction of twisting for lateral line of the core wire, it curvature of the lateral line is characterized Rukoto appeared substantially parallel to the axis by. The term “irregular cross-section” as used herein means a cross-sectional shape other than a circle, and includes all those that change from the original shape when twisted. Further, the “curvature portion” means a portion that curves outwardly, such as an arc shape or an ellipse shape.

A second aspect of the inner cable for a push-pull control cable according to the present invention (Claim 4 ) comprises a core wire having a substantially circular cross section and a plurality of side wires twisted around the core wire. The side wires of the book are characterized in that a twisted wire obtained by twisting a wire made of a single wire in the same direction and a wire having a circular cross section or a twisted wire of a plurality of strands are alternately arranged .

A push-pull control cable according to the present invention (Claim 7 ) is characterized by comprising any one of the inner cables and an outer casing for slidably guiding the inner cable.

  The inner cable of the present invention (Claim 1) has low sliding resistance and high load efficiency when inserted into the outer casing and pushed and pulled. The reason why the sliding resistance is lowered in this manner is that the side wire twisted around the core wire having a substantially circular cross-sectional shape is formed into a twisted structure obtained by twisting a wire having an irregular cross-section, so that a normal strand inner (side wire) Compared with the inner cable with a circular cross-section of strand or stranded wire), the ratio of the gaps between adjacent side wires (clearance in the circumferential direction), that is, the porosity increased, and the air resistance inside the cable decreased. Also, it is considered that the area in contact with the inner surface of the outer casing is reduced, so that the sliding resistance is lowered. Moreover, since the side line itself is twisted, it is also considered that the void ratio is high and the holding power of a lubricant such as grease is high.

Further, a part of the deformed cross-sectional shape is a curvature portion, and the twist direction of the side line is opposite to the spiral direction of twisting with respect to the core wire of the side line, whereby the curvature portion of the side line of the deformed cross-section is substantially the same as the axis. since to appear in parallel, a portion in contact with the inner surface of the outer casing is substantially parallel to the axis, therefore, a more sliding resistance decreases.

The second aspect of the inner cable for the push-pull control cable of the present invention (Claim 4 ) is slightly lower in load efficiency than the aforementioned inner cable (Claim 1) in which all the side lines are twisted lines. There is an advantage of lowering the sliding resistance by lowering the rigidity, and the sliding resistance is lower and the load efficiency is higher than the conventional strand inner.

The push-pull control cable of the present invention (Claim 7 ) employs the above-described inner cable, so that the minimum bending radius can be reduced.

  Next, embodiments of the inner cable and the push-pull control cable of the present invention will be described with reference to the drawings. 1 is a cross-sectional view showing an embodiment of the inner cable of the present invention, FIG. 2 is an enlarged end view of a side line used for the inner cable, FIG. 3 is a schematic perspective view of the inner cable of FIG. 1, and FIG. Sectional drawing which shows one Embodiment of the outer casing used for a push pull control cable, FIG. 5 a and FIG. 5 b are each the end views which show other embodiment of the inner cable of this invention, FIG. 5 c is an enlarged view of the C section of FIG. 6 is a cross-sectional view showing another embodiment of the outer casing according to the present invention, FIGS. 7a, 7b, and 7c are cross-sectional views of the inner cables of Comparative Examples 1, 2, and 3, respectively, and FIG. FIG. 9 is a schematic side view showing a measuring device for measuring a buckling load.

  An inner cable 10 shown in FIG. 1 includes a core wire 11 and side wires 12 twisted in a spiral manner around the core wire 11. The core wire 11 can be substantially the same as that used for a conventional inner cable. Although it depends on the force to be transmitted, the diameter of the core wire 11 is usually about 0.8 to 3 mm, preferably about 1.2 to 1.6 mm. In the case of an AT cable that transmits a force of 100 to 300 N, the diameter of the core wire 11 is about 1 to 1.6 mm, and the diameter of the inner cable 10 as a whole is about 2 to 3.5 mm. The core wire 11 has a circular cross section, and a single metal wire such as an oil tempered wire (such as JIS G 3560), a galvanized steel wire galvanized on a hard steel wire (such as JIS G 3506), or stainless steel (such as JIS G 4314). Used. However, it may be a stranded wire.

  The side line 12 has a substantially oval cross section and is twisted (see FIG. 3). In the case of FIG. 1, both ends are semicircular and the middle is a substantially rectangular oval shape in which the semicircles are connected by straight lines, and the ratio of the width B to the length L of the rectangular portion 13 is 1: It is about 1.2 to 1: 1.3. The radius R of the semicircular portion 14 at both ends is ½ of the width B of the rectangular portion 13. However, both ends are not limited to semicircles, and may be arcs. The total length L0 including the semicircular portion 14 of the cross-sectional shape of the side wire 12 is about 0.3 to 0.9 times the diameter of the core wire 11, and preferably about 0.35 to 0.5 times. Moreover, the cross-sectional shape of the side line may be an ellipse having no left and right straight portions.

  Such a cross-sectional shape of the side line 12 can be obtained by rolling a commercially available metal wire having a circular cross section. In this case, the semicircular portion 14 or the circular arc portion can be constrained by a mold to specify the shape, or can be a semicircular or circular arc shape that is naturally obtained by rolling in the released state. For the rolling process, for example, cold roll rolling that passes between rolls at normal temperature is employed. However, hot rolling may be used. It can also be formed by drawing using an oval die.

  As shown in FIG. 3, the pitch P1 of the twist (side twist) of the side wire 12 is 0.2 to 0.4 times the pitch P2 of the spiral (parent twist) when twisted around the core wire 11. Specifically, it is about 3.5 to 15 mm. When the side twisting pitch P1 is matched with the parent twisting pitch P2, the center line C of the oval shape always faces the radial direction of the core wire 11, but the side twisting pitch P1 is usually the parent twisting. Is smaller than the pitch P2. The material of the side wire 12 may be the same as that of the core wire 11 described above, or may be a combination of different metal materials.

  The direction of twisting of the main twist and the side twist can be the same, but it is preferable to make them reverse. For example, the parent twist is S twist and the side twist is Z twist. Thus, by making it reverse, the semicircle part 14 of the side line 12 becomes substantially parallel to the axis line T, and sliding resistance decreases (refer FIG. 3). In FIG. 3, the cross section of the side line 12 is represented by an ellipse in order to simplify the drawing. Further, the boundary 15 between the semicircular portion and the rectangular portion is indicated by a solid line. Thus, the boundary 15 is undulating, but is substantially parallel to the axis T.

  In order to manufacture such an inner cable 10, a wire rod having an oval cross section is manufactured in advance by the above-described processing method, and twisted around the core wire 11 while being twisted, or in advance by a dedicated machine or the like. A method of twisting to the core wire 11 with a twisting wire machine and the like is adopted. It should be noted that, after the twisting process, a process of giving a twist of a spiral of a parent twist may be performed, and then twisted together. In that case, there is an advantage that it is difficult to be separated.

  Furthermore, when the side wire 12 is twisted to the core wire 11, a die may be used for the voice portion (portion where the strand is twisted), and the outer diameter may be corrected to a substantially circular shape. Thereby, the deformed shape when twisted can be corrected, and the familiarity with the outer casing is improved. The molding rate of the manufactured inner cable 10 (the ratio of the spiral height of the strands that loosen the rope and the diameter of the rope before unraveling as a percentage) is about 85 to 95%.

  The inner cable 10 configured as described above has a small minimum bending radius and a small backlash. And load efficiency is high and the buckling load is maintaining the conventional level.

  The aforementioned inner cable 10 is applied with grease and then inserted into, for example, the outer casing 20 shown in FIG. The outer casing 20 of FIG. 4 includes a liner 22 at the center, a shield layer 23 made of a large number of metal strands twisted around it, and a covering layer (protective layer) 24 provided on the outer periphery thereof. The liner 22 is a tube made of a synthetic resin having high strength and slipperiness, and is made of high density polyethylene (HDPE), ultra high molecular weight polyethylene (UHMWPE), polybutylene terephthalate (PBT), polyacetal (POM), polyamide (PA), fluorine. Resins or their elastomers are used.

  As the metal wire constituting the shield layer 23, SWO-A or SWO-B carbon steel oil tempered wire of JISG3560 is used as in the conventional one. The coating layer 24 is made of polypropylene (PP) or the like. The outer diameter of the outer casing is about 7 to 10 mm in the case of an AT cable or MT cable.

  The cross-sectional shape of the side line 12 in FIG. 2 is a substantially oval shape in which two opposing sides of a rectangle are projected outward in an arc shape, but the side line 27 used in the inner cable 26 shown in FIG. In addition to projecting the two opposite sides 27a and 27a outward, the other two opposite sides 27b and 27b are recessed inwardly in a circular arc shape, so-called a weight-shaped cross-sectional shape. Yes. The radius of curvature R of the arcuate side 27a protruding outward is substantially matched with the radius of the torsion line. The radius of curvature of the side 27b that is recessed inward is larger than the radius of the torsion line.

  Since the inner cable 26 having the torsion wire having such a recessed surface as the side line 27 has a recessed portion, the void ratio is high and the air resistance is low. In addition, the grease retention is high. Therefore, sliding resistance is low and load efficiency is high. The remaining two opposing sides 27b and 27b may also be projected outward in an arc shape within a range that does not become circular as a whole.

  In the above-described embodiment of the side line, each of the two side portions has a curvature portion in which two opposite sides of a rectangle project in an arc shape, but one to three sides of a triangle project in an arc shape, a pentagon, Some sides of a hexagon or a polygon more than a heptagon may be projected in an arc. In that case, in the shape having an even number of sides, basically every other side is projected in an arc shape, but both adjacent sides may be projected in an arc shape. In a shape having an odd number of sides, either one of the adjacent sides protrudes in an arc shape, or neither protrudes. Moreover, you may make all the sides protrude in a circular arc shape in the range which does not become circular as a whole. The side not to be projected may be recessed inward in a shape such as an arc shape as in the case of FIG.

  Furthermore, not only the above-described cross-sectional shape having an arc-shaped protruding side but also a cross-sectional shape having no side protruding in an arc shape, such as a polygon such as a triangle, a quadrangle, and a pentagon, Included in “cross section”. This is because even when the wire rod having such a cross-sectional shape is a twisted wire, a large gap is formed between adjacent wire rods when spirally wound around the core wire.

  In the above-described embodiment, all the side lines have an irregular cross section. However, like the inner cable 28 shown in FIG. 5B, the irregular cross section side line 12 may be combined with a side line 28a that is not twisted in a circular cross section. In that case, it is preferable to arrange alternately. Furthermore, instead of the side wire 28a having a circular cross section, a side wire (side strand) 28b made of a twisted wire obtained by twisting a plurality of strands as shown by an imaginary line is adopted, and the side wire 12 having a modified cross section and the side wire 28b having a twisted wire are used. May be combined. Further, these three kinds of side edges 12, 28a, 28b can be combined. Also for the inner cable in which these two or three types of side wires are combined, the effects of increasing the load efficiency and reducing the sliding resistance can be obtained as compared with the conventional inner cable. Further, as shown in FIG. 5c, it is preferable to provide a grease groove 27c for the curvature portion that is in sliding contact with the inner surface of the liner of the outer casing, as shown in FIG. 5c. The grease groove 27c is preferably provided in the side line 12 having a modified cross section in FIGS. 1 and 5b.

  FIG. 6 shows another embodiment of the outer casing used for the push-pull control cable of the present invention. This outer casing 29 is obtained by replacing the cross-sectional shape of the inner cavity 22a of the liner 22 of the outer casing 20 of FIG. 4 with a hexagon. It may be a pentagon or a heptagon. When the cross-sectional shape of the inner cavity of the liner 22 is made polygonal in this way, in addition to the gap between the side lines, the porosity between the side line and the liner 22 is increased, the sliding resistance is low, and the load efficiency is increased. .

  Next, the effects of the inner cable of the present invention will be described with reference to examples and comparative examples.

  [Example 1] An oil tempered wire (JIS G 3560) having a wire diameter of 1.2 mm was used as a core wire. As a side wire, a galvanized steel wire obtained by galvanizing a hard steel wire (JIS G3506) having a wire diameter of 0.45 mm is rolled to obtain a thickness (width B in FIG. 2) of 0.3 mm and a length (the whole in FIG. 2). Length L0) of 0.52 mm, a twist (side twist) pitch of 5.4 mm, and a twist (twist) direction Z twist. Ten side wires were twisted to the core wire and twisted to an S twist at a pitch of 17.9 mm to produce an end face-shaped inner cable of Example 1 shown in FIG. Finally, the outer diameter was corrected using a die with an inner diameter of 2.2 mm for the voice part.

  [Example 2] An inner cable of Example 2 was manufactured in the same manner as Example 1 except that the side twist pitch was 6.8 mm and the parent twist pitch was 22.4 mm.

  Example 3 An inner cable of Example 3 was manufactured in the same manner as in Example 1 except that the side twist pitch was 8.1 mm and the parent twist pitch was 26.9 mm.

  [Example 4] An inner cable of Example 4 was manufactured in the same manner as in Example 3 except that the material of the side wire was SUS304WPB.

  [Comparative Example 1] An inner cable 30 having a cross-sectional shape of an outer diameter of 2.2 mm shown in FIG. As the core wire 11, an oil tempered wire having a wire diameter of 1.1 mm and a material of Si—Cr—V steel (SWOSC-V) was used. Ten galvanized steel wires having a wire diameter of 0.46 mm and a material of JIS G3506- (SWRH62A) (galvanized) SW-B were used as the side wires 12a of the first layer. Ten stainless steel wires having a wire diameter of 0.23 mm and a material of SUS304-WPB were used as the side wires 12b of the second layer. The twist pitch was 15 mm and the twist direction was Z twist.

  [Comparative Example 2] An inner cable of Comparative Example 2 was manufactured in the same manner as Comparative Example 1 except that the twist pitch of the main twist (rope twist) was 25 mm.

  [Comparative Example 3] An inner cable 31 having an outer diameter of 2.2 mm shown in FIG. As the stranded wire side strand 32, a stainless steel wire 32a having a wire diameter of 0.2 mm and a material of SUS304-WPB, and six stainless steel wires 32b having a wire diameter of 0.18 mm and a material of SUS304-WPB, a twist pitch Five pieces having an outer diameter of 0.56 mm were used by twisting with 6.2 mm and Z-twisting. As the single side wire 33, five galvanized steel wires having a wire diameter of 0.39 mm and a material of JIS G3506 (SWRH62A) (galvanized) SW-B were used and alternately arranged with the side strands 32 of the stranded wire. Other than that, it was the same as Comparative Example 1.

  [Comparative Example 4] An inner cable of Comparative Example 4 was produced in the same manner as Comparative Example 3, except that the twist pitch of the parent twist was 25 mm.

  [Comparative Example 5] An inner cable 34 having an outer diameter of 2.2 mm shown in FIG. As the stranded wire side strands 35, three stainless steel wires having a wire diameter of 0.26 mm and a material of SUS304 were twisted together by a Z-twist with a twist pitch of 5.8 mm to an outer diameter of 0.58 mm. As the single side wire 36, five stainless steel wires having a wire diameter of 0.39 mm and a material of SUS304 were used. Otherwise, it was the same as Comparative Example 3.

[Load efficiency (only PULL)]
About the inner cable of said Example and a comparative example, load efficiency and no-load sliding resistance were measured with the measuring apparatus 40 shown in FIG. The measuring device 40 is provided with a part 42 of a 700 mm long outer casing (model No. 507W71D) 41 having a radius of 150 mm and inverted 180 degrees, passing an inner cable 43 having a length of 1000 mm, and one end with a force of 200 N by a spring 44. The force applied to the other end was measured with a load cell (load cell) 45.

  The pulling stroke was 30 mm. A silicone grease as a lubricant was applied to the inner cable 43 thinly and uniformly on the surface of the inner cable. The load efficiency ηw was calculated by “(force applied to the other end / 200 N) × 100 (%)”. Table 1 shows the measurement results of Examples 1 to 4 and Comparative Examples 1 to 5.

  The outer casing of the model number 507W71D used for the measurement has a cross-sectional shape of FIG. 4, and a polytetrafluoroethylene (PTFE) tube having an outer diameter of 3.95 mm and an inner diameter of 2.4 mm is used as the liner 22. 20 hard steel wires having an outer diameter of 0.7 mm, spirally wound around the liner 22 at a pitch of 75 mm, and the outer layer 24 is made of polypropylene (PP). 1 mm.

[No-load sliding resistance]
The spring 44 was removed from the measuring device 40 of FIG. 8, the inner cable 43 was pulled in an unloaded state, and the unloaded sliding resistance was measured with a load meter 45. Table 1 shows the measurement results of Examples 1 to 4 and Comparative Examples 1 to 5.

[Backlash]
In the apparatus of FIG. 8, the load meter 45 was removed, one end of the inner cable 43 was fixed, and the back and forth stroke at the other end was measured to measure backlash. The results are shown in Table 1.

[Buckling load]
The buckling load was measured with the measuring device 46 shown in FIG. This measuring device 46 is connected to a load meter 45 after passing through the hole of the seat 47 through the lower part of the inner cable 43 cut so that the lap stroke (reference LS in FIG. 9) is 60 mm, and the guide pipe 48 at the upper part. Then, the load was measured when buckling occurred in the inner cable 43 by pressing the rod 49 with an outer diameter of 5 mm and 6 mm from the upper end at a compression speed of 10 mm / min. Table 1 shows the measurement results for Examples 1 to 4 and Comparative Examples 1 to 5.

  From the above, it can be seen that the inner cables of Examples 1 to 4 have a load efficiency of 88 to 89%, which is superior to the inner cables of Comparative Examples 1 to 5 of 78 to 84%. As for the no-load sliding resistance, the inner cables of Examples 1 to 4 are about 3.5 to 4.5 N, and the inner cables of Comparative Examples 1, 2, 4, and 5 are 5 to 7.5 N. It can be seen that it is superior to that of Comparative Example 3 of 4.5N. On the other hand, the backlash is 1.0 to 1.1 mm in the inner cables of Examples 1 to 4, which is superior to 2.5 to 2.6 mm in Comparative Examples 1 to 5. Further, the buckling load is 700 to 1010 N in the inner cables of Examples 1 to 4, and is equivalent to Comparative Examples 1 to 5.

It is sectional drawing which shows one Embodiment of the inner cable of this invention. It is an expanded end elevation of the side line used for the inner cable of FIG. It is a schematic perspective view of the inner cable of FIG. It is sectional drawing which shows one Embodiment of the outer casing used for the push pull control cable of this invention. 5a and 5b are end views showing another embodiment of the inner cable of the present invention, and FIG. 5c is an enlarged view of a portion C in FIG. 5a. It is sectional drawing which shows other embodiment of the outer casing in connection with this invention. 7a, 7b, and 7c are cross-sectional views of the inner cables of Comparative Examples 1, 2, and 4, respectively. It is a schematic side view which shows the measuring device which measures load efficiency. It is a schematic side view which shows the measuring device which measures a buckling load. It is sectional drawing which shows an example of the conventional inner cable.

Explanation of symbols

10 Inner cable 11 Core wire 12 Side wire 13 Rectangular portion 14 Semicircular portion R Radius B Width L Length L0 Overall length P1 Pitch P2 Pitch C Centerline T Axis 15 Boundary 20 Outer casing 21 Push-pull control cable 22 Liner 22a Cavity 23 Shield layer 24 Cover layer 26 Inner cable 27 Side wire 27a, 27b Side 27c Grease groove 28 Inner cable 28a Side wire 28b Side wire (side strand)
29 Outer casing 30, 31 Inner cable 32 Stranded wire side strand 33 Single wire side wire 34 Inner cable 35 Stranded wire side strand 36 Single wire side wire 40 Measuring device 41 Outer casing 42 Inverted part 43 Inner cable 44 Spring 45 Load meter 46 Measuring device 47 Seat 48 Guide pipe 49 Rod

Claims (7)

It consists of a core wire with a substantially circular cross section and a plurality of side wires twisted around the core wire,
The side wire is a twisted wire obtained by twisting a wire having an irregular cross section made of a single wire in the same direction.
Push-pull in which a part of the deformed cross section is a curvature portion, and the twist direction of the side line is opposite to the spiral direction of twisting with respect to the core wire of the side line, so that the curvature portion of the side line appears substantially parallel to the axis line Inner cable for control cable. The side line has a semicircular shape at both ends and the middle is a straight line connecting the semicircles, or two opposing sides of a rectangle project outward in an arc shape, and the remaining two opposing sides The inner cable for a push-pull control cable according to claim 1, wherein the inner cable has a cross-sectional shape that is recessed in an arc shape .   The inner cable for a push-pull control cable according to claim 1 or 2, wherein the twisting pitch of the single wire constituting the side wire is smaller than the twisting pitch of the side wire with respect to the core wire.   A core wire having a substantially circular cross section and a plurality of side wires twisted around the core wire, wherein the plurality of side wires are twisted in the same direction by twisting a wire made of a single wire, and a circular cross section Inner cable for push-pull control cable, which is an array of alternating wires or multiple strands of strands. The twisted wire has a semicircular shape at both ends and a middle shape connecting the semicircles with a straight line, or two opposing sides of a rectangle project outward in an arc shape, and the remaining two opposing sides The inner cable for a push-pull control cable according to claim 4, wherein the inner cable has a cross-sectional shape that is indented in an arc shape inwardly .   The inner cable for a push-pull control cable according to claim 4 or 5, wherein a twisting pitch of the twisted wire is smaller than a twisting pitch of the side wire with respect to the core wire.   A push-pull control cable comprising the inner cable according to claim 1 and an outer casing that slidably guides the inner cable.