JPH0717215Y2 - Cable clamp mechanism - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable clamp mechanism having a clamp for holding a cable to be installed.

[0002]

2. Description of the Related Art Conventionally, generally, a plurality of insulated electric wires in which a copper stranded wire made of an electric soft copper wire as an element wire is covered with an insulator such as vinyl are twisted together, and an insulating outer sheath made of rubber or the like is further provided around the wires. There is known a cable clamp mechanism which is used for a cable provided with a cable and which holds a predetermined position of the cable which is installed between devices and the like.

For example, in the excavator disclosed in Japanese Utility Model Publication No. 2-54888, a cable is wound around a cable reel, and a connector attached to one end of the cable pulled out from the cable reel is attached to an excavation bucket. It is connected to the provided connector box.
And in such an excavator, the clamp 20 as shown in FIG. 6 attached to the excavation bucket so that the tensile force of the cable is not directly applied to the connection portion with the connector.
1, the connector and the clamp 201 are provided with a slack to hold the cable 207 at a predetermined position and support the tensile force.

This clamp 201 has two blocks 2
Between 03a and 203b, cushioning rubber 205a and 205b
The cable 207 from both sides via the
The block 203a and 203b are tightened by the nut 211 and the cable 207 is clamped.
On the other hand, the cable reel is provided with a spiral spring, and as the excavation bucket moves, the cable is pulled out from the cable reel against the spiral spring. , The cable is being rewound.

[0005]

However, in such a conventional device, especially when starting to pull out the cable from the cable reel, the length of the cable wound around the cable reel is long, and the weight of the cable reel and the winding of the cable reel. The weight of the combined cables is heavy. Therefore, when the cable reel is started to rotate, the cable is subjected to a large impact force and a tensile force against the force of the spiral spring and an inertial force due to the weight of the cable.

For example, after excavating the excavation hole with the excavation bucket to take in the soil inside, the excavation bucket is pulled up to the outside of the excavation hole, and the excavation bucket is diced up and down to remove the soil from the excavation bucket. It may vibrate. Due to the small vertical vibrations, the large impact force and tensile force described above are repeatedly applied to the cable.

At this time, the insulating jacket of the cable clamped by the clamp 201 and the cushion rubber 2 of the clamp 201
There is a large frictional force between 05a and 205b, and slippage is unlikely to occur. However, due to repeated impact force and tensile force, slippage occurs between the insulating outer sheath and the insulated wire inside it, leaving the insulating outer sheath in the clamped portion by the clamp,
The insulated wire inside moves in the direction in which tensile force is applied.

By moving only the insulated wire, the insulating jacket between the cable reel and the clamp 201 stretches,
Eventually, there was a case where it broke, resulting in poor insulation. Also, the cable 207, which initially had a slack between the connector and the clamp 201, eliminates the slack because the insulated wire moves in the direction in which the tensile force is applied, and the tensile force is connected to the connector. In some cases, the copper stranded wire of the insulated electric wire was broken by being directly applied to the portion, resulting in an electrical connection failure.

SUMMARY OF THE INVENTION Therefore, the present invention has an object to solve the above problems and provides a cable clamp mechanism which prevents damage to a cable and prevents insulation and electrical connection failure.

[0010]

In order to achieve such an object, the present invention has the following constitution as a means for solving the problem. That is, a cable clamp that is used for a cable in which a plurality of insulated electric wires in which copper stranded wires are covered with an insulating material are twisted together, and further has an insulating jacket around the cable, and that has a clamp that holds a predetermined position of the cable to be installed In the mechanism, a structure of a cable clamp mechanism structure is characterized in that a clamp bar is provided at the clamp, the clamp bar extending at right angles to the erection direction of the clamped cable and winding the cable at least once. That is it.

[0011]

In the cable clamp mechanism of the present invention having the above-described structure, when the cable is wound around the clamp bar at least once, the clamp holds the cable at a predetermined holding position, and when a tensile force is applied to the cable. In the part wound around the clamp bar, the insulated wire and the insulation jacket tighten the clamp bar more tightly, and the entire cable receives a tensile force.

[0012]

Embodiments of the present invention will be described in detail below with reference to the drawings. As shown in FIG. 3, the excavator has a sheave 4 rotatably supported at the tip of a boom 2 provided on a self-propelled main body 1, and a wire rope 8 which is unwound or wound up by a winch 6 on the sheave 4. The kelly bar 10 is wound around the wire rope 8 so as to be rotatably suspended by the swivel joint 12 and the winch 6 is driven, so that the kerry bar 10 can be moved up and down.

A rotary drive device 16 is provided at the tip of the arm 14 supported by the boom 2. The kelly bar 10 is inserted into the rotary drive device 16 and driven by the rotary drive device 16. 10 is a rotary drive device 1
It is configured so that it can slide up and down in 6 to move up and down. Further, a bottom expanding bucket 1 having bottom expanding blades 19 is provided at the tip of the kelly bar 10.
8 is attached.

Then, high-pressure hydraulic oil supplied from a hydraulic unit (not shown) provided in the main body 1 through a hydraulic hose 20 is wound on a hose reel 24 arranged on a rotary table 22 of the rotary drive unit 16. The bottom expanding blades 19 can be opened and closed by supplying / discharging to / from a hydraulic cylinder (not shown) of the bottom expanding bucket 18 via a hydraulic hose (not shown).

A control unit 30 is mounted on the rotary table 22 as shown in FIG. 4, and the control unit 30 is connected to a cable 34 described later via a slip ring (not shown) of a cable reel 32. It is electrically connected. The cable reel 32 is rotatably supported by a support base 36 fixed on the rotary table 22 and includes a spiral spring (not shown). The cable reel 32 is rotated so that the cable 34 is paid out. At this time, the spiral spring is configured to be wound up. The rotary table 22 rotates together with the kelly bar 10 but does not move up and down.

As shown in FIG. 5, the cable 34 is provided with a core wire 40 at the center, and insulated wires 42 are twisted around the core wire 40 at a predetermined pitch. This insulated wire 42
Is a copper stranded wire 44 obtained by twisting thin wires such as annealed copper wire or tin-plated annealed copper wire with an insulator 46 such as rubber or vinyl. In this embodiment, the insulated wire 42 is
It is a six-core cable 34 having a book.

On the other hand, the core wire 40 extends more when the same load is applied to the core wire 40 than when the twisted insulated electric wire 42 extends when a load is applied to the cable 34 without the core wire 40. It is formed of a material having low stretchability. At the same time, the core wire 40 is made of an insulating material so as not to deteriorate the insulating property of the cable 34 itself. In this embodiment, one kind of aromatic polyamide fiber having high tensile strength (280 kgf / mm ² ) is also used.

A protective material 48 such as polyester tape is wound around the twisted insulated electric wire 42,
On the outer side of the protective material 48, a shielding layer 50 formed by braiding tin-plated annealed copper wire or the like is provided. Furthermore, the barrier layer 5
An insulating outer skin 52 formed of an insulating material such as rubber is provided on the outside of 0.
Has been applied. The blocking layer 50 does not necessarily have to be applied.

Next, the cable 3 is provided at two predetermined locations which will be described later.
The first clamp 62 and the second clamp 100 that clamp 4 in between.
Will be described. As shown in FIG. 1, the first clamp 62 includes two blocks 64a and 64b, and the facing surfaces 65a and 65b of the blocks 64a and 64b are
Grooves 66a and 66b having a substantially semicircular cross section, which are slightly larger than the outer diameter of the cable 34, are formed in a linear shape.

Then, in each of the grooves 66a and 66b, buffer rubbers 68a and 68b having a substantially semi-cylindrical shape having an inner diameter substantially equal to the outer shape of the cable 34 are mounted.
When the cable 34 is sandwiched between a and 68b, the opposing surface 65
It is configured such that there is a gap between a and 65b. Further, the blocks 64a and 64b are connected to each other by the grooves 66a and 66b.
Fastening bolts 70 and nuts 72 are provided for tightening on both sides.

Further, as shown in FIGS. 1 and 2, the bar fixing portion 74 integrally extending from the one block 64b along the longitudinal direction of the groove 66b has an outer diameter of about 2 of the cable 34. A guide groove 76 having a double width and deeper than the outer diameter of the cable 34 is formed along the longitudinal direction of the groove 66b. On both sides of the guide groove 76, the facing surfaces 65b are provided.
A bar fixing surface 78 parallel to the bar fixing surface 78 is formed.

The clamp bar 80 has a cylindrical winding portion 82 having a length slightly shorter than the width of the guide groove 76.
Is provided in the center, and on both sides of the winding portion 82, there are provided flat fixing surfaces 84 formed by cutting in a bow-shaped cross section. When the fixing surface 84 is brought into contact with the bar fixing surface 78 of the block 64b, the distance between the bottom surface 77 of the guide groove 76 and the winding portion 82 is set to be slightly smaller than the outer diameter of the cable 34.

Further, the clamp bar 80 has grooves 66a, 66.
With the fixing surface 84 and the bar fixing surface 78 in contact with each other so as to extend perpendicularly to the longitudinal direction of b, the clamp bar 80
And a fixing bolt 86 and a nut 88 for fixing the bar fixing portion 78 to each other.

The second clamp 100 includes the first clamp 62.
It has the same configuration as the above, and includes blocks 102a and 102b, cushioning rubbers 103a and 103b, fastening bolts 104 and nuts 106, bar fixing portions 107, clamp bars 108, fixing bolts 110 and nuts 112, and the like.

On the other hand, one end of a spring 92 is engaged with a spring receiving portion 96 provided upright from a flange 94 attached to the bottom expanding bucket 18. And the spring 92
The other end of is fixed to the second clamp 100 by a fixing bolt 110 and a nut 112 via a connecting member 90.

A guide hole 98, which is larger than the outer diameter of the connector 120 at the tip of the cable 34 and smaller than the first clamp 62, is formed in the flange 94. A cylindrical holding member 124 is provided upright around the guide hole 98 so that the first clamp 100 can be housed in the holding member 124. And
A base plate 125 is provided at the lower end of the holding member 124, which is detachable and has a slit 126 through which the cable 34 passes.

After passing the cable 34 through the guide hole 98 of the flange 94, the length to the tip of the cable 34 has a sufficient margin with respect to the length between the flange 94 and the connector box 122. At a predetermined first position of the groove 66 in which the cushion rubbers 68a and 68b of the first clamp 62 are mounted.
It is sandwiched between a and 66b, and fastening bolt 70 and nut 72
The cable 34 is clamped by tightening the blocks 64a and 64b together.

Further, the cable 34 is wound around the winding portion 82 of the clamp bar 80 once, the fixing surface 84 is brought into contact with the bar fixing surface 78, and the fixing bolt 86 and the nut 88 are tightened to fix the clamp bar 80 to the bar fixing portion. It is fixed to 74. The bottom surface 77 of the guide hole 76 and the winding portion 82 sandwich the cable 34 and extend downward.

Then, the first clamp 62 is attached to the holding member 1
After being inserted into 24, the floor plate 125 is fixed to the holding member 124, and the cable 34 is extended downward from the slit 126. Then, the connector 120 at the tip of the cable 34 is connected to the connector box 122.

On the other hand, in the second clamp 100, a predetermined second position closer to the cable reel 32 than the first position is sandwiched between blocks 102a and 102b, and a cable 34 is sandwiched by tightening with a fixing bolt 110 and a nut 112. is doing.

Further, the cable 34 is connected to the clamp bar 108.
Wrap around the clamp bar 108, and attach the clamp bar 108 to the bar fixing portion 10.
It is fixed to 7 and extended downward. Second position and first
The position is sandwiched between the second clamp 100 and the first clamp 62, and the cable 34 is designed to sag when the force of the spiral spring of the cable reel 32 and the force of the spring 92 are balanced and stationary. There is.

As described above, the connector box 122 is attached to the bottom expanding bucket 18 that moves up and down as the kerry bar 10 moves up and down. On the other hand, a hydraulic cylinder (not shown) of the bottom expanding bucket 18 is provided with a detection sensor (not shown) for detecting the amount of movement of the piston or the lot of the hydraulic cylinder. Then, based on various signals and the like input from the detection sensor via the connector box 122, the cable 34, etc., the expansion degree of the bottom expanding blade 19 can be controlled.

Next, the operation of the cable clamp mechanism of this embodiment will be described. The winch 6 is operated by the operator, the wire rope 8 is paid out, and the bottom expanding bucket 18 is lowered together with the kelly bar 10 into the straight hole A. Then, while controlling the expansion degree of the bottom expanding blade 19, the bottom portion of the straight hole A is expanded and excavated. After excavating a predetermined amount of earth and sand, the bottom expanding blade 19 is closed, and the excavated earth and sand is stored in the bottom expanding bucket 18.

Then, the winch 6 is rolled up, and the bottom expanding bucket 18 is pulled up to the ground. Then, the bottom cover (not shown) of the bottom expanding bucket 18 is released, and the earth and sand in the bottom expanding bucket 18 are discharged.

When the bottom expanding bucket 18 descends, the flange 94 also descends as it descends, and the spring receiving portion 96,
The second clamp 1 via the spring 92 and the connecting member 90.
Pull 00 downward. On the other hand, the second clamp 100 is pulled upward by the spiral spring of the cable reel 32,
The cable 34 tightens the clamp bar 108 tighter.

At this time, the insulated wire 42 and the insulating outer skin 52
Respectively, the clamp bar 108 of the second clamp 100.
Since they are tightened more tightly, the clamp bar 80 is less likely to be displaced, and the insulated wire 42 and the insulation outer skin 52 are also less likely to be displaced. Then, the cable 34 as a whole and the second clamp 100
Receives a tensile force between and.

The spring 92 is pulled and gradually extends, and the downward pulling force of the second clamp 100 gradually increases, and finally the cable reel 32 rotates. In addition, the first clamp 62 and the
The cable 34 between the clamp 100 and the clamp 100 also gradually extends and sometimes becomes a straight line.

In this case, the flange 94 also lowers the first clamp 62 and pulls it downward together with the second clamp 100. On the contrary, the second clamp 100 causes the cable reel 3 to move.
The second spiral spring also pulls the first clamp 62 upwards via the spring 92 and the cable 34
Tighten the clamp bar 80 of the clamp 62 more tightly.

At this time, the insulated electric wire 42 and the insulating jacket 52 of the cable 34 tighten the clamp bar 80 more tightly, and the clamp bar 80 is less likely to be displaced. Therefore, the insulated wire 42 and the insulation jacket 5
The two cables are unlikely to be displaced from each other, and the entire cable 34 is subjected to a tensile force.

At the same time, the cable 34 is connected to the first clamp 62.
Tighten the clamp bar 80 of the
2. Since the insulating jacket 52 tightens the clamp bar 108 of the second clamp 100 more tightly, the insulated wire 42 and the insulating jacket 52 are less likely to be displaced from each other,
The entire cable 34 is subjected to a tensile force.

Although the first clamp 62 and the second clamp 100 are provided in this embodiment, the first clamp 6
Only one of the second clamp 100 and the second clamp 100 may be used. The second clamp 100 serves to reduce the tensile force when pulling out the cable 34 by the action of the spring 92 and prevent a large tensile force from being directly applied to the cable 34.

On the other hand, when rising, the cable reel 3
The cable 34 is pulled up by the force of the second spiral spring to return to its original state. In this case, the cable reel 3
Due to the force of the spiral spring 2, the second clamp 100
Is pulled upward and the cable 34 is connected to the second clamp 1
00 clamp bar 108 is tightened more tightly. Then, the insulated wire 42 and the insulating outer skin 52 form the clamp bar 1.
Since 08 is tightened more tightly, the clamp bar 80 is less likely to be displaced from each other, and the insulated wire 42 and the insulation jacket 52 are also less likely to be displaced from each other. Further, the tensile force is received by the entire cable 34.

As described above, when the cable 34 is pulled out or rewound from the cable reel 32, particularly when the pulling out is started, the first clamp 62 and the second clamp 62
The clamp 100 is pulled upwards and the cable 34 tightens the clamp bars 80, 108 tighter. At this time, the insulated wire 42 of the cable 34 and the insulating jacket 52 tighten the clamp bars 80 and 108 more tightly, so that the clamp bars 80 and 108 are less likely to be displaced. Then, the insulated wire 42 and the insulating outer skin 52
It is difficult for the cables 34 to be displaced from each other, and the entire cable 34 receives a tensile force.

Therefore, the insulating outer cover 52 is stretched while being displaced from the insulated electric wire 42, and is not broken or the like, so that the insulation failure can be prevented. In addition, the first clamp 62
In addition, between the connector 120 and the connector 120, slack is maintained in the portion where the cable 34 has slack, and tensile force is not applied to the connection portion with the connector 120, and electrical connection failure due to breakage of the insulated wire 42 is prevented. can do.

The present invention is not limited to such an embodiment as described above, and can be implemented in various modes without departing from the gist of the present invention. For example, it can be effectively implemented even for the cable 34 without the core wire 40.

[0046]

As described in detail above, in the cable clamp mechanism of the present invention, the clamp clamps the cable at a predetermined clamping position, and when a tensile force is applied to the cable, the cable clamps the clamp bar and the insulated wire and Since the gap between the insulating outer skins is unlikely to occur and the tensile force is applied to the entire cable, it is possible to prevent the cable from being damaged and prevent the insulation property and the electrical connection from being defective.

[Brief description of drawings]

FIG. 1 is a perspective view of a cable clamp mechanism according to an embodiment of the present invention.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a schematic configuration diagram of an excavator having a cable clamp mechanism according to the present embodiment.

FIG. 4 is a front view of the excavating device of the present embodiment.

FIG. 5 is a cross-sectional view of the cable of this embodiment.

FIG. 6 is a front view of a conventional cable clamp mechanism.

[Explanation of symbols]

34 Cable 42 Insulated Wire 44 Copper Strand 46 Insulator 52 Insulation Shell 62 1st Clamp 80 Clamp Bar 100 2nd Clamp 108 Clamp Bar

Claims (1)

[Scope of utility model registration request] 1. A cable, which is used for a cable having a plurality of insulated electric wires in which a copper stranded wire is covered with an insulating material, is twisted around each other and has an insulating outer sheath, and which is provided with a clamp for holding a predetermined position of the erected cable. In the clamp mechanism, the cable clamp mechanism is characterized in that the clamp is provided with a clamp bar extending at right angles to the erection direction of the clamped cable and capable of winding the cable at least once.