JPH0529849Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Detailed Description of the Invention] The present invention is a cable drive device for a wire saw that is used to circulate a cutting cable at a required running speed and tension when wire sawing reinforced concrete structures, etc. Regarding.

[Conventional technology]

The wire sawing method is a method of cutting the object by wrapping a cutting cable around the object and circulating it while pulling it with a cable drive device. This is a cutting method that was used in some parts of the world.

An example of such a cutting cable is one in which cutting beads having a layer of diamond abrasive grains and coil springs or other spacers are alternately fitted into a wire rope, and stoppers made of steel rings or the like are crimped at required intervals. used.

The wire sawing method includes a cable drive pulley and its rotational drive mechanism that frictionally runs the wound cutting cable at a required speed, and a tension applying means that applies the required tension to the running cutting cable. A cable drive for a wire saw comprising at least one cable drive is usually used.

As the tension applying means, a mechanism is generally adopted in which the cutting cable is pulled while circulating by winding it up with a winch, applying weight with a counterweight, or the like. However, especially in wire sawing of reinforced concrete structures, the cable drive device is used to pull the cutting cable along pre-installed rails or racks, because the power can be obtained according to the cutting situation and it is easy to control. It is preferable to adopt a mechanism that allows the device to move by itself in the direction in which it is stretched.

[Problem that the invention attempts to solve]

In the above-mentioned wire sawing method for reinforced concrete structures, the worker does not have to engage in cutting work on the side of the object to be cut unlike in the case of normal cutting methods that use blades, etc. The cable drive device at a remote location can be manually operated, remotely operated, or automatically operated with or without intervention.

In the above wire sawing, when the cutting cable is circulated at a running speed of 15 to 40 m/sec and a tension of 50 to 200 kg on the tension side, when the object to be cut is stone, which is the object of conventional wire sawing. The cutting cable is generally made of a granular aggregate of relatively low hardness, such as limestone, and is generally a unitary structure, so the tensile load applied to the cutting cable is relatively small, and the variation in the tensile load is also small. Therefore, in this case, the cutting cable circulates at a substantially constant running speed and tension during wire sawing, and the cable drive device also operates steadily and stably. Furthermore, in this case, the diamond beads are consumed before the wire rope breaks due to fatigue, so there is almost no interruption in the operation of the cable drive device due to wire rope breakage during wire sawing.

However, when the object to be cut is a reinforced concrete structure, it is composed of a concrete layer and reinforcing bars arranged vertically and horizontally within it, so the situation is different from that when cutting a homogeneous stone with low hardness. On the other hand, the tensile load applied to the cutting cable increases and decreases irregularly during cutting, and increases dramatically when the cutting moves from the concrete layer to the reinforcing steel or when the cutting cable gets caught in the reinforcing steel. So,
The cable drive device repeats intermittent and irregular movements, and the cutting cable also tends to cause wavy movements while running. Such a phenomenon makes steady operation of the cable drive device difficult, places an excessive load on the device itself and guide pulleys placed in the middle, and causes wavy irregularities and steps on the cut surface of the workpiece. However, there were problems such as the need to chisel and rework the cut surface after wire sawing. Furthermore, if a running cutting cable is exposed to abnormal tensile loads or fluctuations in tensile loads as mentioned above, the wire ropes that make up the cable will stretch and metal fatigue will occur, and even a small amount of tension during cutting may cause There were also problems such as easy breakage.

Therefore, it is preferable and necessary that the operation of the cable drive device, that is, the rotation of the cable drive pulley and the adjustment of the tensile force of the tensioning means, etc., be made to respond immediately to the above-mentioned fluctuations in the tensile load. The cable drive device for the saw is
Since there is no means for quantitatively grasping the tensile load applied to the cutting cable and its fluctuations, it has been difficult to use, especially for wire sawing of reinforced concrete structures.

An object of the present invention is to provide a cable drive device for wire sawing of reinforced concrete structures, etc., which can be operated appropriately according to the tensile load applied to the cutting cable during wire sawing.

[Technical means to solve problems]

The cable drive device for wire sawing of reinforced concrete structures, etc. according to the present invention includes a cable drive pulley that frictionally runs a wound cutting cable, a rotation drive mechanism thereof, and a tension force that applies a required tension to the running cutting cable. The apparatus is characterized in that it includes at least a applying means, further comprising a strain detecting means for detecting displacement of the rotating shaft of the cable drive pulley that occurs in response to a tensile load applied to the cutting cable.

[Effect of invention]

During wire sawing, the cutting cable circulates between the cable drive pulley of the cable drive device and the object to be cut at the required running speed and tension, bending via guide pulleys along the way as necessary. At the same time as the cutting cable is pulled by the cable drive pulley, the cable drive pulley is also constantly pulled by the reaction force to the tension of the cutting cable. When the cutting cable moves from cutting the concrete layer to cutting the reinforcing steel, the tensile load increases and at the same time the tension increases, so the cable drive pulley is pulled even harder by the cutting cable.

The strain detection means in the present invention detects the displacement of the rotating shaft of the cable drive pulley that occurs based on the tensile force received by the cable drive pulley, and therefore, the tension applied to the cutting cable can be determined from the detected value. It is possible to grasp the load quantitatively and immediately.

As a specific example of the above-mentioned strain detection means, for example, the displacement of the rotation shaft of the cable drive pulley itself that occurs in response to the tensile load applied to the cutting cable, and therefore the displacement or rocking of the rotation shaft of the cable drive pulley with respect to the device frame. In these cases, the bearing on the side of the rotation axis of the cable drive pulley close to the cable drive pulley is mounted so as to be able to be slightly displaced with respect to the device frame, and the movable bearing A strain detector may be attached as a bridge between the cable drive pulley and the device frame, or the strain detector may be attached to the rotating shaft of the cable drive pulley itself. There is no limitation on the type of strain detector used in these cases, whether it is a contact type or a non-contact type, or the type of detection principle.

In addition, in order to always maintain good conditions for wire sawing, an alarm is issued based on the detected value from the strain detection means, and the displacement of the rotation axis of the cable drive pulley is kept within a set range. To this end, an automatic control system may be introduced that automatically rotates the cable drive pulley, adjusts the tensioning force of the tensioning means, etc.

〔Example〕

Hereinafter, the present invention will be specifically explained based on embodiments shown in the drawings. In FIGS. 1 and 2, which are a schematic plan view with the lid opened and a schematic side view with the lid opened, respectively, of an example of the cable drive device for wire sawing of reinforced concrete structures, etc. according to the present invention, the cable drive device for wire sawing of reinforced concrete structures, etc. A cable drive pulley rotating shaft 3 is rotatably mounted on the apparatus frame 2 of 1 through bearings 4a and 4b at both ends, and a cable drive pulley 5 is attached to one end of the shaft, and a driven pulley 6 is attached to the other end. Further, the bearing 4a on the cable drive pulley 5 side is attached to the device frame 2 so as to be movable within a minute range of 2 to 3 mm. Furthermore, a strain detector 7 is attached to the front and back of the movable bearing 4a and the device frame 2 with screws 8a, 8b so as to bridge them, and the detected value is displayed on a display 9 on the top surface of the device frame 2. Ru. In the device frame 2, in front of the cable drive pulley 5,
A tension side tension pulley 10 and a slack side tension pulley 11 are rotatably arranged vertically adjacent to each other in the same plane.

In addition, there are axles 12 at the front and rear of the bottom of the device frame 2.
a, 12b are rotatably mounted on axles, and chain gears 13a, 13 are mounted at intermediate portions of these axles 12a, 12b.
b. Wheels 14...14 are attached to both ends, and a conduction chain 15 is suspended between the front and rear chain gears 13a, 13b via a tension gear 34. In addition, a torque limiter 1 is attached to the front axle 12a.
6 output side is fitted.

Furthermore, the device frame 2 includes an electric motor 17, a hydraulic continuously variable transmission 35, and an electromagnetic two-stage switching speed reducer 18.
is mounted, and the drive pulley 19 of the electric motor 17
A transmission belt 21 is hooked between the drive pulley 6 at the end of the rotation shaft 3 of the cable drive pulley via a tension pulley 20, and the drive pulley 19 of the electric motor 17 and the pulley 37 on the input side of the transmission 35. Transmission belts 24 and 39 are also placed between the transmission belt 35 output side pulley 38 and the reducer 18 input side pulley 22, respectively. A conduction chain 27 is connected between the chain gear 26 on the input side of the machine 16 and the chain gear 26 .

On the other hand, as shown in FIG. 3, which is a schematic side view illustrating the usage state of the cable drive device for wire sawing of reinforced concrete structures, etc. according to the present invention, the cable drive device 1 for wire saws described above is shown in FIG.
is installed so that its front, rear, left and right wheels 14...14 fit into a rail 29 laid on a road surface 28, and a guide pulley stand 30 is anchored to the end of the road surface 28. The guide pulley stand 30
The vertical guide pulleys 31a and 3 are arranged in upper and lower two stages.
1b. A horizontal girder 32 protrudes into the sea below in the direction of the paper. Further, the cutting cable 33 is connected to guide pulleys 31a and 31b on the way.
It is endlessly hung on the cable drive pulley 5 and the horizontal girder 32 via the tension pulley 10 on the tight side and the tension pulley 11 on the loose side.

In the above configuration, when the electric motor 17 is rotated, the rotation is caused by the driving pulley 19, the driven pulley 6, and the cable drive pulley rotating shaft 3.
etc., to rotate the cable drive pulley 5, while at the same time, the rotation is transmitted to the main drive pulley 19, transmission 35, reduction gear 18, torque limiter 1.
6, etc., to the front and rear axles 12a, 12b.
And the wheels 14...14 are rotated to urge or move the cable drive device 1 rearward along the rail 29. When the cable drive device 1 is operated in this manner, the cutting cable 33 circulates at the required running speed and is pulled backward with the required tension, so that the horizontal girder 32 in the sea can be easily cut. be done.

During wire sawing as described above, the cable drive pulley 5 receives a reaction tensile force that corresponds to the strength of the tensile load applied to the cutting cable 33, so the cable drive pulley rotation shaft 3 is connected to the fixed bearing on the driven pulley 6 side. 4b as the center, within the movable range of the movable bearing 4a on the cable drive pulley 5 side, and the displacement of the rotation axis is detected by the strain detector 7, and the detected value is determined, for example, by the length, weight, etc.
It is displayed digitally or analogously on the display 9 depending on the ratio and the like. Since this detected value corresponds to the tensile load applied to the cutting cable 33 that is running, the operator can check the running status of the cutting cable 33 that cannot be easily seen from the outside from the detected value and its changes. It is possible to grasp the wire sawing situation including the cutting progress of the object to be cut, the cutting situation of the reinforcing bar, and the degree of wear of the cutting beads, etc., which can be effectively utilized for the appropriate operation of the cable drive device 1. .

In addition, the torque limiter 16 controls the tension of the cutting cable 33 and the rearward biasing force of the cable drive device 1, that is, the axle 12, so that the tensile load applied to the cutting cable 33 does not become excessive.
a, 12b is used to limit the rotational torque within a set range, and if such torque limiting means and load limiting means are adopted in the cable drive device 1 for wire sawing of reinforced concrete structures, etc. according to the present invention, it will be more excellent. Wire sawing becomes possible.

Note that the above embodiments do not limit the present invention. For example, instead of a rail-type self-propelled feeding mechanism as a means of applying tension to the cutting cable,
The cable drive device may be biased or moved rearward by a self-propelled feeding mechanism consisting of a rack and pinion or a counterweight type biasing mechanism,
In addition, by winding the cutting cable with a winch without moving the cable drive pulley,
The cutting cable may be pulled backwards. In those cases, when introducing torque limiting means or load limiting means, use a suitable torque limiting device, load limiting device, etc. between the cutting cable tensioning means and its drive source in the same way as above. It is sufficient to intervene.

[Effect of idea]

As described above, in the cable drive device for wire sawing of reinforced concrete structures, etc. according to the present invention, the tensile load applied to the cutting cable during wire sawing is detected by the displacement of the rotating shaft of the cable drive pulley, and the Based on the value, the rotation of the cable drive pulley in the cable drive device, the tensile force of the tension applying means, etc. can be adjusted manually or automatically as appropriate, so it is possible to adjust the rotation of the cable drive pulley in the cable drive device, the tensile force of the tension applying means, etc. as appropriate, so that it is possible to adjust the rotation of the cable drive pulley in the cable drive device, the tensile force of the tension applying means, etc. as appropriate. It can be suitably used for intermittent wire sawing due to sudden changes in cutting load when cutting from reinforcing bars to concrete or from concrete to reinforcing bars.

Therefore, in that case, efficient and stable wire sawing and a good cut surface can be obtained, and the load on the cutting cable is reduced, making it possible to prevent premature breakage. Unforeseen accidents caused by scattering can be prevented.

[Brief explanation of the drawing]

1 and 2 are a plan view and a schematic side view of an example of a cable drive device for wire sawing of reinforced concrete structures, etc. according to the present invention, respectively, with the lid opened, and FIG. FIG. 2 is a schematic side view illustrating a usage state of the cable drive device for wire sawing. Explanation of main symbols, 1...Cable drive device, 2
...Device frame, 3...Cable drive pulley rotating shaft, 4a, 4b...Bearing, 5...Cable drive pulley, 7...Strain detector, 12a, 12b...
...Axle, 14...Wheel, 16...Torque limiter,
17...Electric motor, 18...Reducer, 33...Cutting cable, 35...Transmission.

Claims (1)

[Claims for Utility Model Registration] 1. A device equipped with a cable drive pulley that frictionally runs a wound cutting cable, its rotational drive mechanism, and a tension applying means that applies a required tension to the running cutting cable. A cable drive device for wire sawing of reinforced concrete structures, etc., characterized in that it is equipped with strain detection means for detecting displacement of the rotating shaft of a cable drive pulley that occurs in response to a tensile load applied to a cutting cable. 2. The wire for reinforced concrete structures, etc., according to claim 1 of the utility model registration claim, wherein the strain detection means detects the displacement of the cable drive pulley rotating shaft relative to the device frame, which occurs in response to a tensile load applied to the cutting cable. Cable drive for sawing. 3. A utility model in which the strain detection means is constructed by attaching a bearing near the cable drive pulley of the rotation axis of the cable drive pulley so that it can be displaced with respect to the device frame, and attaching a strain detector between the movable bearing and the device frame. A cable drive device for wire sawing of reinforced concrete structures, etc. as claimed in claim 2.