JPH0729472Y2 - Cable tension measuring device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a cable tension measuring device for measuring the tension at the time of laying / removing a cable in the work of laying / removing a power cable.

[Problems to be solved by conventional techniques and devices]

In general, when laying or removing power cables,
In order to prevent excessive tension from being applied to the cable, it is necessary to measure the resistance of the pipeline, which increases due to the bends and steps of the pipeline.
Conventionally, a device as shown in Japanese Utility Model Publication No. 56-38883 has been used, and this device is as shown in FIG. 9, in which a is a vehicle and b is a wire winding. Catch, c
Indicates a capstan, and d indicates a guide wheel. The capstan c is supported on the turntable e,
The guide wheel d is attached to the tip of an arm g protruding from the turntable e. f is a vertically movable leg attached to the rear end of the vehicle. A tension detecting tool h using a strain gauge is provided between the lower part of the leg body f and the ground, and the tension detecting tool h measures the cable tension. Furthermore, in order to check the relationship between the position of the wire (cable) and the cable tension, the length of the wire was measured from the rotation amount of the capstan c. However, there is a problem that a measurement error occurs when the capstan c idles due to excessive tension applied to the wire. Also, the actual exploitation 62
A tension measuring device described in No. 26109 is known, and this device has a winch for pulling up a wire and a winch attached to a vehicle, and one end thereof is pivotally supported by a pivot shaft so as to be vertically swingable. It was equipped with a fine movement frame and a load cell that receives the middle of the fine movement frame and measures the tension of the wire. However, in this tension measuring device, since the wire is pulled up by the winch in a state close to horizontal, the difference between the wire tension and its vertical component force becomes extremely large, and the accuracy of wire tension measurement by the load cell becomes poor. There was a problem. Moreover, in order to correct the difference between the wire tension and the vertical component force, the load cell is slid to adjust the horizontal position of the load cell. Therefore, the load cell was easily damaged.

Then, this invention aims at solving the said problem.

[Means for Solving the Problems]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a winch for pulling up a wire connected to a cable on a vehicle, and a fine movement in which the winch is attached and one end of which is pivotally supported by a pivot shaft. A frame, a winding drum that winds the wire from the winch, and a measuring device that measures the length of the wire are mounted, and the wire is suspended between the winding drum and the winch to wind the wire. The measuring pulley is provided with a measuring pulley that also functions as a traverser that reciprocates in the axial direction of the drum, and a load cell that receives the other end of the fine movement frame and measures the tension of the wire is installed on the vehicle. And the horizontal position of the winch is arranged intermediate between the load cell and the pivot, and the horizontal distance from the pivot to the winch is shorter than the horizontal distance from the pivot to the load cell. Constant, and the wire to be pulled up to the winch, in which was suspended from between the load cell and pivot shaft.

[Action]

When the wire is pulled up by the winch, the tension applied to the wire is converted into a force (load) applied to the load cell by the fine movement frame with the pivot as the fulcrum, and measured by the load cell. Since the horizontal distance from the pivot shaft to the winch and the horizontal distance from the pivot shaft to the load cell are known, the tension applied to the wire can be calculated by converting the load applied to the load cell by calculation. Since this wire is pulled up with a winch from between the load cell and the pivot shaft vertically or slightly inclined from the vertical, the difference between the wire tension and the vertical component force becomes zero or negligibly small, and the load cell load Does not need to be corrected.
Further, since the horizontal distance from the pivot to the winch is set shorter than the horizontal distance from the pivot to the load cell, the load applied to the load cell can be made smaller than the wire tension. Further, when the winch spins due to excessive tension applied to the wire, the running of the wire is stopped and the rotation of the measuring pulley is stopped, so that there is no error in measuring the length of the wire.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

1 and 2 show an embodiment of the cable tension measuring device according to the present invention. The cable tension measuring device comprises a rectangular base frame 1 in a plan view, a fine movement frame 2 pivotally supported by the horizontal pivot shaft 3 on the base frame 1, and a winch 5 attached to the fine movement frame 2.
And a load cell 4 for measuring the tension of the wire 6 connected to the cable, and the entire cable tension measuring device is mounted on the vehicle 7. Furthermore, on the vehicle 7,
A wire winding device 9 having a winding drum 16 for winding the wire 6 from the winch 5 and a measuring device 22 for measuring the length of the wire 6 are mounted, and the measuring device 22 is a winding device. A measuring pulley 10 that doubles as a traverser that suspends a wire 6 between a drum 16 and a winch 5 and reciprocates in the axial direction of the winding drum 16 is provided. A hole through which the wire 6 passes is formed below the winch 5 (since the winch 5 pulls the wire 6 linked to the cable) on the base frame 1, the fine movement frame 2, and the loading platform of the vehicle 7. 7a are outriggers for fixing the vehicle 7 at a predetermined position, and are provided at four positions on both front and rear sides of the vehicle 7.

As shown in FIG. 3, the base frame 1 and the fine movement frame 2 are held substantially parallel to each other, and one end of the fine movement frame 2 is pivotally supported on the base frame 1 by a pivot shaft 3 so as to be vertically swingable. The other end of the fine movement frame 2 is
It is received by the load cell 4 for measuring the wire tension, which is fixed on the vehicle 7. In the illustrated example, the load cell 4 is attached to the base frame 1. Also, the horizontal position of the winch 5 is arranged in the middle of the load cell 4 and the pivot shaft 3, and the horizontal distance r ₁ from (the axis center point of) the pivot shaft 3 to the winch 5 is set to the pivot shaft 3 ( horizontal distance r ₂ from the Jikukokoroten) to the load cell 4
Set shorter than. Here, the horizontal distance r ₁ is from the vertical line 1 (on the side of the pivot 3) contacting the winch 5 to the pivot 3
Is the horizontal distance to. Further, the wire 6 pulled up by the winch 5 is hung from between the load cell 4 and the pivot 3 in a vertical state or a state in which the wire 6 is slightly inclined.
Further, the supporting projections 17, 17 and the holding member 1 are provided outside the load cell 4.
A lock mechanism 8 composed of 8, 18 is provided. Support protrusion
17, 17 are fixed to the fine movement frame 2, and the holding members 18, 18 are composed of a bolt pivotally attached to the base frame 1 and two nuts screwed to the bolt. The lock mechanism 8 is used for the load cell 4 such as when the vehicle 7 travels.
This is to prevent unnecessary load such as vibration from being applied to the load cell 4 when it is not used.

1 to 3, the wire 6 connected to the cable
Is taken up by the drum 16 of the wire take-up device 9 from the manhole through the winch 5 and the measuring pulley 10. The winch 5 pulls up the wire 6.

Here, θ is an angle formed by the wire 6 with respect to the vertical line 1-called a "wire exit angle"-, F ₁ is a cable tension, F is a vertical component of the tension F ₁ , F ₂ is a load cell load, and F _{3 is} Is the winding tension. Since the winding tension F ₃ is so small as to be negligible as compared with the cable tension F ₁ (F ₃ << F ₁ ), the following equation is derived in FIGS. 1, 3, and 5.

In this way, the cable tension F ₁ is obtained from the equation. Then, a load of F ₂ = r ₁ / r ₂ · F is applied to the load cell 4. The cable tension F ₁ can be directly read by converting the load F ₂ applied to the load cell 4 and the wire exit angle θ (or the correction value 1 / cos θ) into an electric signal, converting the electric signal, and displaying the electric signal.

Fig. 4 shows a block diagram of the measuring method using this cable tension measuring device, and shows the load F ₂ applied to the load cell 4.
Is converted into an electric signal V ₂ ′, and this is converted into a load cell amplifier 25
Amplify with, input to the calculator 24 as the signal V ₂ , and output angle θ or its correction value (1 / cos θ) to the calculator 24 manually or automatically by the angle detector. , Is input, the arithmetic unit 24 calculates the following equation.

That is, This is converted and displayed on the display 20, and simultaneously recorded by the recorder 21. The formula is based on the formula described above.

In this way, the load cell amplifier 2
5, calculator 24, input device or angle detector for the exit angle θ,
A display 20, a recorder 21, etc. are also installed. Further, as shown in FIGS. 1 and 2, a measuring device 22 having a measuring pulley 10 is provided to measure the length of the wire 6 and thus the length of the cable connected to it.

FIG. 8 shows the case where the recording of the recorder 21 is output to the chart paper 26, and the cable tension F ₁ is displayed.
Further, the measuring pulse line 27 is displayed simultaneously with the display of the cable tension F ₁ . As shown in the block diagram of FIG. 4, the pulse line 27 transmits a pulse from the measuring device 22 for each predetermined cable length (wire length) and displays it on the recorder 21 and on the display 20. Displays the product of the set value of how many meters per pulse corresponds to the pulse count number, and displays the scale value.

As described above, the load cell load F ₂ is measured by the load cell 4, and this value F ₂ and the wire exit angle (θ) or the correction value (1 / cos θ) therefor are input to the calculator 24, The cable tension F ₁ is calculated and displayed, and in parallel with this, the pulse from the scale unit 22 is counted to perform the scale measurement, and the recorder 21 and further (if desired) the display unit 20.
Is displayed (see FIG. 4).

The display device 20 is a display such as an LED display device, and it is convenient that the cable tension can be checked at the same time as the work of laying or removing the cable is proceeding. Also recorder
Simultaneously with or immediately after the above-mentioned construction, 21 can check the cable tension and its relationship with the position, is convenient for guiding the conduit resistance, and is also convenient for record keeping.

Actual usage conditions are shown in FIGS. 6 and 7. FIG. 6 shows the installation of the cable 19, and FIG. 7 shows the removal of the cable 19 for reuse. In the case of laying, as shown in Fig. 6, a worker enters the manhole 15 on the cable 19 side and the cable 19
Is pulled into the manhole 15, is connected to the grip portion 12 of the wire 6, and the cable tension is measured while pulling the wire 6 with the winch 5. In the case of removal, as shown in FIG. 7, an operator enters the manhole 15, connects the gripping part 12 of the wire 6 to the cable 19, and makes the size of the cable 19 from the ground to the pipeline 14 one stroke, When the wire 6 goes up to the ground, disconnect it from the cable 19 and re-manhole 15
Then, the cable 19 is connected to the conduit outlet portion of the cable 19 and pulled up. While repeating this operation, the cable tension is also measured until the cable 19 is removed. In both works, the cable tension measurement and the measurement of the cable 19 by the measuring device 22 are performed at the same time, so the work can be performed while monitoring the tension.

It should be noted that the present invention is not limited to the above-described embodiments, and design changes can be freely made without departing from the scope of the present invention. For example, either a case where an angle measuring device for measuring the angle θ is attached, or a case where the operator visually measures the angle θ and manually inputs the approximate value to the calculator 24 may be used.

[Effect of device]

Since the present invention is configured as described above, it has the great practical effects described below.

Since the wire 6 is pulled up by the winch 5 vertically or slightly inclined from the vertical, the difference between the tension F _{1 of the} wire 6 and its vertical component force F becomes zero or negligibly small, and at the load cell 4. The tension F ₁ of the wire 6 (cable) can always be measured accurately.

Due to the lever action, the load F ₂ applied to the load cell 4 is
The tension F ₁ can be reduced to r ₁ / r ₂ . for that reason,
Since the load cell 4 having a small capacity can be used, the cost can be reduced.

Since the position of the load cell 4 is fixed, the load cell 4 is unlikely to be damaged by abrasion and has a long life.

When excessive tension is applied to the wire 6 (cable), the winch 5 spins idle, and the running of the wire 6 stops, the measurement pulley 10 also stops rotating, so that the measurement error of the length of the wire 6 does not occur. The relationship between the position of 6 (cable) and the cable tension can be accurately checked. Further, since the measuring pulley 10 is also used as the traverser, the number of parts can be reduced.

[Brief description of drawings]

1 is a side view showing an embodiment of the present invention, FIG. 2 is a plan view, FIG. 3 is a side view of essential parts, FIG. 4 is a block diagram, FIG. 5 is an explanatory view, FIG. 6 and FIG. FIG. 7 is a simplified use explanatory diagram, and FIG. 8 is a plan view showing an example of a chart paper. FIG. 9 is a simplified explanatory view showing a conventional example. 1 ... Base frame, 2 ... Fine movement frame, 3 ... Pivot shaft, 4 ... Load cell, 5 ... Winch, 6 ... Wire, 7 ... Vehicle.

Continuation of the front page (56) Reference JP-A-3-259723 (JP, A) Actual opening Sho 62-26109 (JP, U) Actual opening Sho 62-25836 (JP, U) Actual opening Sho 60-137338 (JP , U) Showa 54-166381 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A winch for pulling up a wire linked to a cable on a vehicle, a fine movement frame having one end pivotally attached to the winch and being vertically swingable by a pivot shaft, and a winch from the winch. A winding drum for winding the wire and a measuring device for measuring the length of the wire are mounted, and the wire between the winding drum and the winch is suspended to reciprocate in the axial direction of the winding drum. A measuring pulley that also serves as a moving traverser is provided in the measuring device, a load cell that receives the other end of the fine movement frame and measures the tension of the wire is fixed on the vehicle, and A horizontal position is arranged between the load cell and the pivot shaft, and the horizontal distance from the pivot shaft to the winch is set shorter than the horizontal distance from the pivot shaft to the load cell. A cable tension measuring device characterized in that the pulled wire is hung from between the load cell and a pivot.