JP2926018B2 - Wire tension detecting device and wire tension detecting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for detecting a wire tension in a wire drawing apparatus used for construction of a transmission line.

[0002]

2. Description of the Related Art In recent overhead wire construction work, it is required to more accurately manage wire drawing conditions in order to improve the quality of wire drawing. In particular, the necessity of accurately managing the wire tension applied to the cable during wire drawing has increased, and therefore, it is necessary to detect the wire tension with high accuracy. For this reason, for example, Japanese Patent Application Laid-Open No. 56-155160 and Japanese Utility Model Publication No. 57-10
A wire drawing device incorporating a tension detecting mechanism as disclosed in Japanese Patent Publication No. 176 has been widely used.

[0003] On the other hand, many of the extension devices currently used for overhead line construction of transmission lines were manufactured in an era when there was little interest in managing the extension tension, and were provided with a tension detecting mechanism. There is also the fact that there is not. When using a wire drawing device that is not equipped with such a tension detection mechanism, it is necessary to install a wire tension meter or the like on a steel tower or the like to detect the wire tension. For some reason, it hasn't really been implemented. In other words, although the necessity is recognized, it is a fact that the wire tension is not sufficiently managed in the wire drawing work using the wire drawing device without the tension detecting mechanism.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances. Even when a wire drawing device without a wire tension detecting mechanism is used, the present invention is not applicable to the case where a wire tension detecting mechanism is provided. It is an object of the present invention to be able to detect the extension tension under the same conditions as in the wire apparatus. More specifically, it is an object of the present invention to provide a wire tension detecting device capable of detecting wire tension with high accuracy simply by placing a wire drawing device without a wire tension detecting mechanism thereon.

[0005]

According to the present invention, there is provided a wire tension detecting device, wherein an upper frame is movably combined with a lower frame, a load transmitting section is provided on the upper frame, and a load receiving section is provided on the lower frame. Further, a load detecting means interposed between the load transmitting unit and the load receiving unit is provided, and a wire drawing device is mounted on the upper frame and used. The wire tension of the wire drawing device mounted on the upper frame is increased. Due to the mobility of the frame, the load is transmitted from the load transmitting section to the load receiving section via the load detecting means.

[0006] The tension detection in this extension wire tension detection device is performed as follows. When the wire drawing device is placed on the upper frame and fixed in a state where movement before and after the wire drawing device is regulated, a tension load applied to the wire drawing device is transmitted to the upper frame. Since the upper frame is movable with respect to the lower frame, the upper frame tends to move in the load direction according to the tension load. Accordingly, the tension load is transmitted from the load transmission unit to the load receiving unit via the load detection unit, and as a result, the tension load can be detected by the load detection unit.

[0007] According to such a wire tension detecting device, the wire stretching device is placed on the upper frame while the device is placed on the ground of a work place, and only a fixed state where movement before and after the wire stretching device is restricted is set. Thus, the wire tension can be detected with high accuracy. That is, the wire tension detecting device according to the present invention can be used only by performing the same work as preparing the ground for installing the wire drawing device, and does not substantially increase the work load. In other words, the wire tension detecting device according to the present invention also functions as a base of the wire drawing device, so to speak, and is used in such a manner that the base is also used.
A high-precision wire tension detecting function can be given to a wire drawing device not equipped with a tension detecting mechanism. This makes it possible to more effectively utilize an existing wire drawing device without a tension detection mechanism. That is, it is possible to use a wire drawing device without a tension detecting mechanism as necessary in the same manner as a wire drawing device with a tension detecting mechanism.

The movable combination structure of the upper frame and the lower frame in the above-described wire tension detecting device can have two structures, a shaft structure and a slide structure.
In the shaft structure, the upper frame is provided with a connecting shaft and a slide connecting portion, and the lower frame is configured to hold the first bearing so as to be slidable and to hold load detecting means abutting on the first bearing. A load receiving block, a self-aligning second bearing paired with the first bearing, and a slide receiving portion are provided, and the first and second bearings support the connecting shaft and the slide connecting portion. The upper frame and the lower frame are combined so that the upper frame is movable with respect to the lower frame with the self-aligning second bearing as a fulcrum by the slidable connection in the front-rear direction with the slide receiving portion, and The connecting shaft functions as a load transmitting unit, and the load receiving block functions as a load receiving unit.

With this structure, it is possible to eliminate the influence of the back tension applied to the wire drawing device, and thus it is possible to detect the tension with higher accuracy. The reason will be described below. The wire drawing device applies a brake to a cable supplied from, for example, a drum mount provided at a rear portion thereof, and feeds the cable. The braking force is applied by winding the cable around the wire drawing drum. In order to effectively generate the braking force of the wire drawing drum, it is necessary to apply an appropriate back tension to a cable supplied from a drum mount or the like. However, this back tension acts on the wire drawing device in the direction opposite to the wire drawing tension. In other words, the load on the wire drawing device due to the back tension acts to offset the load on the wire drawing device due to the wire tension. Therefore, when the back tension fluctuates, the detection accuracy of the wire drawing tension decreases due to this effect. I will. However, with the above structure, the cable from the drum mount passes over the second bearing, which is the movable fulcrum of the upper frame, so that the load due to the back tension can be prevented from being transmitted to the load detecting means. . As a result, it is possible to prevent the back tension from affecting the tension detection.

On the other hand, in the slide structure, a slide connection portion is provided on the upper frame, a slide receiving portion is provided on the lower frame, and the slide connection portion and the slide receiving portion are slidably connected in the front-rear direction. The upper frame and the lower frame are combined so that is movable with respect to the lower frame.

This structure cannot eliminate the influence of the back tension unlike the above-mentioned shaft structure, but has the advantage that the position of the wire drawing device on the upper frame can be freely set. . This can be seen by comparison with the shaft structure.

FIG. 7 schematically shows the principle of tension detection in a shaft structure. The connecting shaft S is automatically adjusted to the second position in accordance with the load caused by the wire tension F applied to the cable C.
Going to move as arrows and the bearing B ₂ as a fulcrum. Along with this, the first bearing B ₁ presses against the load detecting means D,
Thus, the load detecting means D detects a load corresponding to the extension tension F. The distance between the second bearing B ₂ and the load detecting means D is defined as La, and the distance between the second bearing B ₂ and the load point, that is, the position P at which the cable C is unreeled from the extension drum is L.
b, R = (Lb / L) is set between the extension tension F applied to the cable C and the load R detected by the load detection means S.
a) · F, from which the extension tension can be determined. Therefore, if La and Lb are not constant, it is necessary to change the set value of the wire tension calculation processing circuit each time, but this is not practical. Therefore, assuming that La which is structurally fixed is not a problem, the mounting position of the wire drawing device on the upper frame is fixed in order to keep Lb which varies depending on the position where the wire drawing device is mounted on the upper frame. Need to be

On the other hand, since the slide structure transmits the extension tension load to the load detecting means by the overall sliding movement of the upper frame with respect to the lower frame, the influence of the mounting position of the extension device on the upper frame. Therefore, the mounting position of the wire drawing apparatus on the upper frame can be freely set. This is of high practical value in view of general on-site working conditions.

[0014]

Embodiments of the present invention will be described below. FIG. 1 shows a schematic structure of a wire tension detector according to a first embodiment.
4 to FIG. As can be seen from these drawings, the extension wire tension detecting device according to the present embodiment has a structure in which an upper frame 1 and a lower frame 2 each formed in a rectangular flat plate structure are movably combined by a shaft structure.

The upper frame 1 has a connection shaft 3 and a pair of left and right slide connection portions 4 on the lower surface thereof. The connecting shaft 3 is fixed in a state of being floated from the lower surface of the upper frame 1 by a pair of left and right fixing brackets 5 and 5 as shown in the example in the figure, or is closely attached to the upper frame 1 or penetrates the upper frame 1. Fix it. As shown in FIG. 4, the slide connection portion 4 has a structure in which a roller 7 for sliding is provided at a distal end portion of a connection bracket 6 protruding from the lower surface of the upper frame 1.

On the other hand, the lower frame 2 has a load receiving block 8 and a self-aligning second bearing 9 (FIG. 2 and FIG. 3) having, for example, a pillow block structure, and a pair of left and right slide receiving portions 11 fixed to the upper surface thereof. Have. The load receiving block 8 is a block housing 1 formed in a square square shape.
2 has a structure in which a first bearing 13 paired with the second bearing 9 and a load cell 14 as load detecting means are held. The first bearing 13 is slidable inside the block housing 12 as indicated by an arrow X in FIG. 1, and the load cell 14 is fixed to the block housing 12 and the load button 14 b is fixed to the first bearing 13. So that The slide receiving portion 11 has a structure having a guide groove 15 corresponding to the roller 7 of the slide connecting portion 4 of the upper frame 1.

The upper frame 1 and the lower frame 2 allow the connecting shaft 3 to be supported by the first bearing 13 and the second bearing 9 and the sliding rollers 7 of the slide connecting portion 4 to be guided by the slide receiving portion 11. The upper frame 1 is movable relative to the lower frame 2 with the self-aligning second bearing 9 as a fulcrum, as shown by an arrow Y in FIG.

As shown in FIGS. 1 and 2, the wire tension detecting device includes a wire drawing device E such as a shoe chain type wire drawing vehicle on an upper frame 1 and a drum D.
The incoming cable C is placed so as to be directly above the second bearing 9, and is used in a state where movement before and after the cable C is restricted. When a tension load is applied to the wire drawing device E in this state, this is transmitted to the upper frame 1. Then, since the upper frame 1 is movable with respect to the lower frame 2 as described above, the upper frame 1 tends to move in the load direction according to the tension load. Along with this, a tension load is transmitted from the connection shaft 3 as a load transmission unit to the load cell 14 as load detection means via the first bearing 13. As a result, the principle that the tension load can be detected by the load cell 14 is shown in FIG.
Is as described above.

The wire tension detector according to the second embodiment slides an upper frame 21 and a lower frame 22 similar to those in the first embodiment, as schematically shown in FIGS. It is a structure that is movably combined depending on the structure.

The upper frame 21 has a load transmitting portion 23 fixed at the center of the lower surface thereof, and has slide connecting portions 24 fixed at four corners. Load transmission unit 23
Is formed so as to protrude from the lower surface of the upper frame 21 with a structure having sufficient bending strength. The slide connecting portion 24
The lower frame 22 has a guide groove 27 corresponding to a roller 26 of a slide receiving portion 25 of the lower frame 22 described later.

On the other hand, the lower frame 22 has a load receiving portion 28 fixed at the center of the upper surface thereof, and has slide receiving portions 25 fixed at four corners. The load receiving portion 28 is formed in the same manner as the load transmitting portion 23, and the load cell 29 is fixed thereto. The slide receiving portion 25 has a structure in which a roller 26 for sliding is provided at a distal end portion of a connection bracket 30 protruding from the upper surface of the lower frame 22, similarly to the slide connection portion 4 in the first embodiment.

The upper frame 21 and the lower frame 22 are combined by supporting the roller 26 of the slide receiving portion 25 in the guide groove 27 of the slide connecting portion 24. It becomes slidable as indicated by the arrow Z in the middle.

As in the case of the first embodiment, this extension wire tension detecting device mounts the extension device E on its upper frame 21 and uses it in a state where its movement before and after is restricted. When a tension load is applied to the wire drawing device E in this state, the tension load is transmitted to the upper frame 21. Then upper frame 2
Since 1 is movable with respect to the lower frame 22 as described above, the upper frame 21 tends to move in the load direction in response to this tension load. Along with this, a tension load is transmitted from the load transmitting unit 23 to the load receiving unit 28 via the load cell 29. As a result, the tension load can be detected by the load cell 14.

[0024]

As described above, the present invention makes it possible to use an existing extension device without a tension detection mechanism in the same manner as an extension device with a tension detection mechanism, thereby increasing the number of wire work. Can contribute to improving the extension quality.

[Brief description of the drawings]

FIG. 1 is a side view of a wire tension detecting device according to a first embodiment.

FIG. 2 is a plan view seen from the direction of an arrow DA in FIG. 1;

FIG. 3 is a side view as viewed from a direction of an arrow DB in FIG. 1;

FIG. 4 is a side view including a partial break seen from the direction of arrow DC in FIG. 1;

FIG. 5 is a side view of a wire tension detecting device according to a second embodiment.

FIG. 6 is a plan view seen from the direction of arrow DE in FIG. 5;

FIG. 7 is an explanatory diagram of a principle of detecting tension in a shaft structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper frame 2 Lower frame 3 Connecting shaft (load transmitting part) 4 Slide connecting part 8 Load receiving block (load receiving part) 9 Second bearing 11 Slide receiving part 13 First bearing 14 Load cell (load detecting means) 21 Upper part Frame 22 Lower frame 23 Load transmitting part 24 Slide connecting part 25 Slide receiving part 28 Load receiving part 29 Load cell (load detecting means) E Wire drawing device

Continuation of front page (56) References JP-A-49-39090 (JP, A) JP-A-59-56133 (JP, A) JP-A-4-25801 (JP, A) JP-B-33-8632 (JP, A) , B1) (58) Field surveyed (Int. Cl. ⁶ , DB name) H02G 1/00-1/06

Claims (2)

(57) [Claims] An upper frame is movably combined with a lower frame, a load transmitting section is provided on the upper frame, a load receiving section is provided on the lower frame, and a load transmitting section is interposed between the load transmitting section and the load receiving section. Provide load detection means, and use the wire drawing device mounted on the upper frame,
A wire tension detecting device adapted to transmit a wire tension in a wire drawing device mounted on the upper frame from a load transmitting unit to a load receiving unit via a load detecting unit by movability of the upper frame, A load bearing block provided with a connection shaft and a slide connection portion in the upper frame, and a load bearing block for holding the first bearing in a slidable manner in the lower frame and holding a load detecting means contacting the first bearing; , A self-aligning second bearing paired with the first bearing, and a slide receiving portion, and a connection shaft supported by the first and second bearings, a slide connecting portion and a slide receiving portion. Slidable connection in the front-rear direction with the self-aligning second bearing so that the upper frame is movable with respect to the lower frame with the fulcrum as a fulcrum.
A wire tension detecting device in which an upper frame and a lower frame are combined, a connecting shaft functions as a load transmitting unit, and a load receiving block functions as a load receiving unit. 2. A wire tension detecting method performed by using the wire tension detecting device according to claim 1, wherein a cable supplied to the wire stretching device is provided on an upper frame of the wire tension detecting device. A method of detecting a wire tension in which a wire drawing device is placed in a state where the wire drawing device passes just above the bearing of the wire drawing, and the wire drawing tension is detected in that state.