JPH0732576Y2 - Clamp for pulling cables - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is intended for use in pulling cables such as cables and wire ropes in bridge construction work such as suspension bridges and other construction work. It is about clamps.

[Conventional technology]

It is often necessary to grasp and pull the cable at a position other than the end of the cable in the overhead wire work when constructing a bridge such as a suspension bridge. For example, in the main cable overhead line construction of a suspension bridge, the prefabricated strand drawn on the catwalk (suspension scaffolding) must be moved from the drawing line to a predetermined line, and sag adjustment must be performed between the main towers and between the main tower and the spray saddle. I have to.

Conventionally, various types of clamps have been proposed for use in cable pulling work.
There is a tensioning clamp disclosed in Japanese Patent Publication No. 41213. Explaining the structure of this tension clamp,
As shown in FIG. 10 and FIG. 11, a movable hardware 28 having a large number of upper tapered planes 27 is placed on the upper portion of a gripping hardware 26 having a semi-circular groove 25 for fitting a cable in the lower portion, and its movement is performed. A washer 30 having a large number of lower tapered planes 29 and reinforcing ribs 35 is placed on the upper part of the metal fitting 28, and the semicircular groove 25
The upper part of the cable 1 is fitted to the lower part of the cable 1, and a large number of U-shaped metal fittings 31 are fitted to the lower part of the cable 1, and a large number of U bolts 32 are fitted to the U-shaped metal fitting 31. 26,
The movable nut 28 and the washer 30 are inserted, and the fastening nuts 33 that engage with the upper surface of the washer 30 are screwed onto both ends of the U bolt 32. The shackle engagement holes are provided on the pulling side of the movable metal 28.
A tow section 14 having 34 is provided.

In the case of this cable pulling clamp, a constant tightening force is applied to the upper tapered flat surface 27 of the moving hardware 28 and the lower tapered flat surface 29 of the washer 30 by the U bolt 32 set across the cable 1, and then the moving hardware By pulling 28, the upper tapered plane 27 of the moving hardware 28 is moved relative to the lower tapered plane 29 of the washer 30, and the wedge effect of each tapered plane increases the tightening force of the cable to improve the clamping performance. It is what makes the work.

[Problems to be solved by the device]

The above-mentioned conventional cable tension clamp can be applied to a cable to which a relatively small tensile force acts, but when the tensile force acting on the cable becomes large, the clamping performance cannot be sufficiently exerted, and the cable 1 Since the lower part is partially tightened via the U-shaped metal member 31 by the U bolts 32 arranged at intervals in the longitudinal direction of the cable, a local compressive force acts on the cable, which may damage the cable. There is.

Further, in the case of the conventional tension clamp, since the taper plane is simply subjected to the usual chrome plating treatment, the frictional resistance is large, and therefore the taper plane 27, 29
Before the relative movement of the
There was a case where sliding occurred between 31 and the cable 1 and the tightening force increase due to the wedge effect could not be sufficiently exerted.

Also, if you want to obtain a large cable pulling force, U bolt
The tightening force of 32 must be increased, which is why the U bolt
It is necessary to increase the number of 32 used or increase the size of the U bolt 32. However, if the size of the U bolt 32 is increased, it becomes difficult to perform the tightening work by human power, and if the tightening force by the U bolt 32 is further increased, U
Even if the shape-matching member 31 is provided, a large local compressive force acts on the cable 1 and the cable 1 may be locally bent and deformed or damaged.

Furthermore, in the case of the above-mentioned conventional tension clamp, since the taper in the moving metal piece 28 and the washer 30 is flat, the shape of the clamp becomes large.

An object of the present invention is to eliminate the drawbacks of the above-mentioned conventional tension clamps, and to provide a compact tension clamp for cables, which is capable of exhibiting sufficient clamp performance even with a large tension force. .

[Means for Solving the Problems]

To achieve the above object, in the cable tensioning clamp according to the present invention, a circular hole 24 is provided inside an inner cylinder 20 divided into a plurality of parts by an axially extending dividing part. On the outside of the outer cylinder 10, a large number of tapered outer surfaces 21 whose radii change in the inner cylinder axial direction are provided side by side in the inner cylinder axial direction, and inside the outer cylinder 10 divided into a plurality of by axially extending dividing portions. , A large number of tapered inner surfaces 11 that match the tapered outer surface are provided side by side in the axial direction of the outer cylinder, and each tapered inner surface 11 of the outer cylinder 10 is in surface contact with each tapered outer surface 21 of the inner cylinder 20 and is divided. The divided parts of the outer cylinder 10 are connected by a connector 13, and a solid coating lubricant is provided on at least one of the tapered inner surface 11 and the tapered outer surface 21,
A traction member engaging portion 14 is provided on the traction member 10.

[Action]

When a tensile force is applied to the outer cylinder 10, the taper inner surface of the outer cylinder 10
11 slides on the tapered outer surface 21 of the inner cylinder 20, and the circular hole 24 of the inner cylinder 20 causes the circular hole 24 of the inner cylinder 20 to move to the outer surface of the cable 1 due to the wedge action of the outer cylinder 10 having the tapered inner surface 11 and the inner cylinder 20 having the tapered outer surface 21. It is strongly tightened against.

〔Example〕

 Next, the present invention will be described in detail with reference to the illustrated example.

1 to 9 show an embodiment of the present invention, in which a cable tensioning clamp according to the present invention comprises a metal inner cylinder 20, a metal outer cylinder 10, and inner and outer cylinders thereof. And a connecting tool 13 for connecting.

As shown in FIGS. 4 to 6, the inner cylinder 20 is divided into two by an axially extending dividing portion and is provided with a pair of inner cylinders having a semicircular cross-section groove 2 that matches the outer shape of the cable. It is composed of units 3 and 4, and each inner cylinder configuration unit 3 and 4
A circular hole 24 is formed by the groove 2 having a semicircular cross section. Outside each inner cylinder unit 3, 4, there are a number of semicircular tapered outer surfaces 2
1 are arranged in series in the axial direction of the inner cylinder, the tapered outer surfaces 21 thereof have the same radius of curvature R over the entire length, and the center point 0 of the radius of curvature R is the axis of the inner cylinder constituting units 3 and 4. It is deviated to the outer side of the central portion in the width direction of the semicircular cross-section groove 2 toward the pulling side in the direction.

The reason that a large number of tapered outer surfaces 21 are arranged in series is to make the clamp shape compact. That is, when a single-step tapered outer surface extending over substantially the entire length of the inner cylinder constituting units 3 and 4 is provided, the wall thickness of the end of the inner cylinder constituting units 3 and 4 on the taper outer surface protruding side is considerably increased due to the taper gradient. However, by providing a large number of tapered outer surfaces 21 side by side in series, it is possible to suppress an increase in the wall thickness of the inner cylinder constituent units 3 and 4, and to obtain the same wedge effect as in the case where a single-step tapered outer surface is provided. Can be demonstrated.

At one end of the inner cylinder forming unit 3 in the circumferential direction,
A plurality of shift-preventing recesses 5 are provided, and a plurality of shift-preventing projections 6 that are fitted into the shift-preventing recesses 5 are provided at an end portion of the other inner cylinder structural unit 4 in the circumferential direction. When setting the outer cylinder 10 at the end of the inner cylinder constituent units 3 and 4 on the opposite side to the pulling side, a stopper 22 for preventing the outer cylinder 10 from slidingly moving to the opposite side to the pulling side is integrated. When the cable 1 is covered with the inner cylinder 20 formed of a pair of inner cylinder constituent units 3 and 4, the inner cylinder constituent units 3 and 4 are prevented from slipping between the end faces in the circumferential direction and the bottom surface of the shift preventing recess 5. When a cable is clamped, a tightening force (compressive force) acts in the radial direction of the cable 1 to reduce the cross section of the cable 1, In order not to press the circumferential ends of the inner cylinder constituent units 3 and 4 against each other, The size of the serial gap is set. Further, the engagement between the shift preventing concave portion 5 and the shift preventing protruding portion 6 prevents the relative shift movement of the inner cylinder constituent units 3 and 4 when the cable tension acts on the clamp.

As shown in FIGS. 7 to 9, the outer cylinder 10 is divided into two by a dividing portion extending in the axial direction, and the inner cylinder 20 is divided.
It is composed of a pair of outer cylinder constituent units 7 and 8 having a large number of taper inner surfaces 11 that match the taper outer surface 21 of each of the outer cylinder constituent units 7 and 8. A recess 16 and a plurality of shift-preventing projections 17 that are fitted into the shift-preventing recess 16 are provided, and flanges 15 are provided on both sides in the width direction of each of the outer-cylinder constituent units 7 and 8, and the outer cylinder is provided. A large number of connecting tool insertion through holes 12 arranged at intervals in the axial direction are provided, and a pulling part having pulling tool engagement holes 9 on both sides in the width direction at the pulling side end of the outer cylinder 10 ( Eye plate) 14 is provided, and when the outer cylinder 10 is covered with the inner cylinder 20, the space between the end faces in the circumferential direction of the outer cylinder constituent units 7 and 8, the bottom surface of the deviation preventing recess 16 and the top of the deviation preventing protrusion 17 are provided. A gap is provided between the surface.

Each tapered outer surface 21 of the inner cylinder 20 and each tapered inner surface 11 of the outer cylinder 10 are precisely machined, and one or both of the tapered outer surface 21 and the tapered inner surface 11 are integrally coated with a solid coating lubricant. The solid film lubricant reduces the sliding resistance between the inner cylinder 20 and the outer cylinder 10. As the solid film lubricant, graphite or molybdenum disulfide can be used, and as a material suitable for outdoor use,
It is preferable to employ a base material such as nickel plating and a fluororesin that has been baked on.

Next, the inner cylinder 20 and the outer cylinder 10 configured as described above are used to assemble and construct the cable tensioning clamp of the present invention, and the cable tensioning work is performed using the tensioning clamp. The procedure for performing the procedure will be described with reference to FIGS.

First, the semi-circular cross-section groove 2 of the pair of inner cylinder constituent units 3 and 4 is fitted to an arbitrary position of the cable (cables) 1, and the shift prevention recess 5 of each inner cylinder constituent unit 3 and 4
And the protrusions 6 for preventing slippage, and then the outer cylinder forming units 7 and 8 are covered on the outer side of the inner cylinder 20 composed of the pair of inner cylinder forming units 3 and 4, and each outer cylinder is formed. Composition unit
The shift preventing recesses 16 and 7 of the shift stoppers 7 and 8 are fitted to each other, and the taper inner surface 11 of each of the outer cylinder constituent units 7 and 8 is fitted.
Are overlapped with the taper outer surface 21 of each inner cylinder constituent unit 3, 4, and both side portions in the width direction of the pair of outer cylinder constituent units 7, 8 constituting the outer cylinder 10 are inserted into the connector insertion through holes 12. The inner cylinder 20 and the outer cylinder 1 are tightened evenly over the entire length of the outer cylinder by a large number of connecting tools 13 made up of bolts and nuts.
A clamp consisting of 0 and a connector 13 is integrally attached to the cable 1. The connecting tool 13 may be a hydraulic jack previously assembled in the outer cylinder without using the bolt and nut, and the outer cylinder may be tightened by the hydraulic jack.

Next, a pulling member connected to a rope of a pulling device (not shown) such as a winch is engaged with a pulling portion 14 formed of an eye plate provided on the pulling side end of the outer cylinder 10 to pull the pulling member. When the outer cylinder 10 is pulled by the device in the direction of arrow C, the tapered inner surfaces 11 of the outer cylinder 10 slightly slide on the tapered outer surfaces 21 of the inner cylinder 20.

In this case, due to the wedge effect of the taper outer surface 21 and the taper inner surface 11, a spreading force is generated between the inner cylinder 20 and the outer cylinder 10, but the expansion deformation of the outer cylinder 10 is restrained by the connector 13. Therefore, the reaction force of the pushing force is transmitted from the circular hole 24 of the inner cylinder 20 to the peripheral surface of the cable 1, and the cable tightening force of the inner cylinder 20 is increased. The cable 1 can be clamped and pulled by the frictional force due to the cable tightening force.

Since the cable surface and the inner cylinder are metal-touch, the coefficient of friction is about 0.2 to 0.3. On the other hand, in the clamp of the present invention, the taper inner surface 11 of the outer cylinder 10 and the taper outer surface of the inner cylinder 20
The friction coefficient of the sliding surface with respect to 21 is 0.1 or less because at least one or both of the tapered inner surface 11 and the tapered outer surface 21 are coated with the solid coating lubricant. Therefore,
When a tensile force is applied to the outer cylinder, slippage occurs between the taper inner surface 11 and the taper outer surface 21 having a small coefficient of friction, but no slippage occurs between the cable 1 and the inner cylinder 20. Since the cable gripping force by the clamp increases as the relative sliding amount between 11 and the tapered outer surface 21 increases,
A large tensile force can be applied to the cable 1.

Although the inner cylinder 20 and the outer cylinder 10 are divided into two in the above embodiment, they may be divided into three or four, or the outer cylinder 10 may be divided into two and the inner cylinder 20 may be divided into three. Alternatively, it may be divided into four.

[Effect of device]

Since the present invention is configured as described above, it has the following effects.

Multiple tapered outer surfaces provided outside the divided inner cylinder 20
21 and a large number of tapered inner surfaces 11 provided inside the divided outer casing 10 exert a wedge effect, so that it is lighter and more compact than a conventional tension clamp having a tapered flat surface. Can be a clamp and inner cylinder
The circular hole 24 of 20 tightens the cable 1, so the cable 1
On the other hand, a surface compressive force acts on the cable, so that a local compressive force does not act on the cable unlike a conventional tension clamp that clamps the cable by using a U bolt. Since the solid coating lubricant is provided on at least one of the tapered outer surface 21 of the inner cylinder 20 and the tapered inner surface 11 of the outer cylinder 10 without damaging the cable 1, the tapered outer surface 21 of the inner cylinder 20 is provided. The friction coefficient between the outer cylinder 10 and the taper inner surface 11 of the outer cylinder 10 can be reliably kept small, so that when the tensile force is applied to the outer cylinder 10 of the clamp, the outer cylinder 10 smoothly slides with respect to the inner cylinder 20. As a result, the wedge effect can be reliably exerted, so that a large cable gripping force can be exerted and the occurrence of slippage between the cable 1 and the clamp can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 9 show an embodiment of the present invention, wherein FIG. 1 is a partial vertical side view of a tension clamp for cables and FIG. A plan view and FIG. 3 are A- of FIG.
A line enlarged sectional view, FIG. 4 is an exploded side view of the inner cylinder, FIG. 5 is a front view thereof, FIG. 6 is an assembled lateral sectional view of the inner cylinder, FIG. 7 is an exploded side view of the outer cylinder, and FIG. The drawing is a front view thereof, and FIG. 9 is an assembled transverse sectional view of an outer cylinder. FIG. 10 is a side view showing a conventional tension clamp, and FIG. 11 is an enlarged sectional view taken along the line BB in FIG. In the drawing, 1 is a cable, 2 is a groove having a semicircular cross section, 3 and 4 are inner cylinder constituent units, 5 is a shift preventing concave portion, 6 is a shift preventing protrusion, 7 and 8 are outer cylinder constituting units, 10 is an outer cylinder, Reference numeral 11 is a tapered inner surface, 12 is a through hole for inserting a connecting tool, 13 is a connecting tool, 14 is a pulling portion, 15 is a flange, 16 is a recess for retaining, 17 is a protruding portion for retaining, 20 is an inner cylinder, and 21 is a tapered outer surface. 22 is a stopper, and 24 is a circular hole.

Claims (1)

[Scope of utility model registration request] 1. A circular hole 24 is provided inside an inner cylinder 20 divided into a plurality of parts by a dividing portion extending in the axial direction.
On the outside of the outer cylinder 10, a large number of tapered outer surfaces 21 whose radii change in the inner cylinder axial direction are provided side by side in the inner cylinder axial direction, and inside the outer cylinder 10 divided into a plurality of by axially extending dividing portions. ,
A large number of tapered inner surfaces 11 adapted to the tapered outer surfaces are provided side by side in the axial direction of the outer cylinder, and each tapered inner surface 11 of the outer cylinder 10 is provided.
Is in surface contact with each tapered outer surface 21 of the inner cylinder 20, and the divided parts of the divided outer cylinder 10 are connected by a connector 13, and at least one of the inner taper surface 11 and the outer taper surface 21 has a solid coating lubrication. A pulling clamp for cables, in which a material is provided and a traction material engaging portion 14 is provided on the outer cylinder 10.