JP4309741B2 - Overhead wire tension balancer - Google Patents

Description

  The present invention relates to an overhead wire tension balancer used for maintaining the tension of an overhead wire such as a train wire.

Overhead lines, especially train lines (suspended / auxiliary suspended / trolley lines) are affected by sag tension due to expansion / contraction due to temperature changes, elastic elongation due to creep and trolley wire wear, and inclination of the support over time. Therefore, it is necessary to keep the tension of the train line constant. A spring-type tension balancer is known as an apparatus for that purpose (for example, Patent Document 1). The tension balancer includes a cylindrical casing connected to the support column, an inner member that is coaxially received in the casing and can be protruded and retracted in the axial direction, and is connected to the overhead wire. The coil spring is coaxially interposed between the casing and the inner member so as to be elastically biased in the direction. This tension balancer is installed with each coil spring being compressed and deformed to some extent under standard installation conditions. Therefore, for example, when the temperature drops and the train line contracts, the inner member protrudes from the outer casing against the repulsive force of the coil spring, and when the temperature rises and the train line extends, the inner member is caused by the resilient restoring force of the coil spring. Can be absorbed in the casing, so that the displacement due to expansion and contraction of the train line can be absorbed.
JP 2000-158981 A

However, the tension change range of the train line that can be handled by the conventional overhead wire tension balancer is ± 10% of the standard tension, and there is a problem that it cannot cope with a large extension / contraction of the train line due to a temperature change.
Accordingly, an object of the present invention is to provide an overhead wire tension balancer that can maintain a constant tension in response to a large extension / contraction of an overhead wire that cannot be absorbed only by extension / contraction of a spring. It is said.

  In order to solve the above problems, in the present invention, an outer casing 3 is interposed between the cylindrical casing 1 in the spring tension balancer and a support member that supports the cylindrical casing 1, and the cylindrical casing 1 is disposed in the outer casing 3. Is received so that it can appear and disappear in the axial direction. Between the outer casing 3 and the cylindrical casing 1, a screw rod 15 and a nut 12 that are screwed together to convert the relative displacement in the axial direction of both into a rotational motion are interposed. A motor 18 is fixed to the outer casing 3 so as to rotationally drive the screw rod 15 or the nut 12 rotatably supported by the outer casing 3 so as to relatively displace the outer casing 3 and the cylindrical casing 1 in the axial direction. Between the cylindrical casing 1 and the inner member 2, a position detection means for detecting the relative position in the axial direction is interposed. Based on the relative position information of the cylindrical casing 1 and the inner member 2 detected by the position detecting means, the rotation of the motor 18 is controlled so as to always arrange them at a predetermined relative position.

  In this way, for example, the limit wire 19a, 19b, 20a, and the like before the hollow wire 2 as an inner member extends into the cylindrical casing 1 due to an increase in temperature, and the spring 5 is fully extended. A position detection means such as 20b detects that the relative position of the cylindrical casing 1 and the inner member 2 is outside a predetermined range, and drives the motor 18 via the control device, for example, to rotate the screw rod 15. Then, the cylindrical casing 1 is pulled and the spring 5 is returned to a predetermined compression deformation state. Conversely, when the train line contracts excessively due to a decrease in temperature, the cylindrical casing 1 is pushed out by the reverse operation, and the spring 5 is returned to a predetermined compression deformation state. Therefore, the predetermined tension of the train line is always maintained. Depending on the length of the screw rod 15, a balancer having a long allowable stroke can be configured in a small size.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 is a longitudinal front view showing an overhead wire tension balancer to which the present invention is applied, FIG. 2 is a plan view with the same part cut away, FIG. 3 is a side view thereof, and FIG. 4 is a sectional view taken along line IV-IV in FIG. FIG. 5 is a longitudinal sectional front view of a part of the tension balancer.

  In the illustrated embodiment, one end side of a hollow rod 2 as an inner member is coaxially received in a cylindrical casing 1 in a nested manner. The hollow rod 2 can protrude and retract in the axial direction with respect to the cylindrical casing 1. The cylindrical casing 1 is received in an outer casing 3 having a rectangular parallelepiped box shape at one end side. The cylindrical casing 1 can protrude and retract in the axial direction with respect to the outer casing 3. The other end of the hollow rod 2 is connected to the train line through the handle 4.

  A coil spring 5 is concentrically interposed between the casing 1 and the hollow rod 2. One end of the coil spring 5 in the axial direction is locked to the outward flange 6 at one end of the hollow rod 2, and the other end is locked to the inward flange 7 at the other end of the cylindrical casing 1. Further, it is assembled in a state where a predetermined initial load is applied.

  An end plate 8 that closes the opening is provided on one end side of the casing 1 (left side in FIG. 1). The end plate 8 has an octagonal shape and extends in a radial direction in a flange shape with respect to the casing 1, and two opposite sides of the end plate 8 are opposed to the opposite side walls 10 of the outer casing 3 via sliding members 9, respectively. Is slidable in the axial direction. A plurality of rollers 11 are interposed between the casing 1 and the inner side of the outer casing 3 to restrict the relative position of the casing 1 in the radial direction within the outer casing 3. A ball nut 12 is attached to the center of the end plate 8.

  An end plate 13 is provided on one end side (the left side in FIG. 1) of the outer casing 3, and a puller 14 for connecting to a support body such as a utility pole is attached to the end plate 13. Inside the outer casing 3, a screw rod 15 that is screwed into the ball nut 12 is provided concentrically with the casing 1. One end side (the left side in FIG. 1) of the screw rod 15 is received so that a rotational force is transmitted into a gear box 16 attached in the outer casing 3. The drive shaft of the gear box 16 is connected to a motor 18 via a speed reducer 17. Therefore, the screw rod 15 is rotated by forward / reverse rotation of the motor 18, and the casing 1 is displaced relative to the outer casing 3 in the axial direction via the ball nut 12. The ball nut 12 may be rotated to move the screw rod 15 in the axial direction.

  As means for detecting the relative position of the hollow rod 2 with respect to the cylindrical casing 1, limit switches 19 a, 19 b, 20 a, 20 b, and 21 and an operating rod 22 that activates the limit switches are provided. The limit switches 19a, 19b, 20a, 20b, and 21 are supported on the operation rod 22 supported by the end plate 8 of the cylindrical casing 1 at a predetermined interval. The attachment rod 23 is supported near the outer periphery of the end plate 8 and extends into the outer casing 3 in parallel with the axis of the cylindrical casing 1.

  The limit switches 24a and 24b are for detecting the relative position (movement limit position) of the cylindrical casing 1 with respect to the outer casing 3, and are fixed to the outer casing 3 so as to extend in parallel with the axis of the cylindrical casing 1. They are mounted on the mounting rod 25 at intervals. The limit switches 24 a and 24 b are operated by being pushed by the end plate 8 of the cylindrical casing 1.

  This tension balancer always absorbs the expansion and contraction of the train line due to temperature change or the like by the expansion and contraction of the spring 5 and keeps the tension constant. However, the train line extends excessively for some reason, and the hollow rod 2 which is an inner member Is pulled into the cylindrical casing 1 and the operating rod 22 activates the limit switch 19a before the standard tension is obtained. As a result, the motor 18 is rotated forward, the screw rod 15 is rotated forward, the cylindrical casing 1 is drawn into the outer casing 3 (leftward in FIG. 1), and the operating rod 22 activates the home position limit switch 21. Controlled to stop at position. With this, the standard tension can be obtained. On the contrary, when the train line contracts excessively for some reason, the hollow rod 2 as the inner member is pulled out from the cylindrical casing 1, but before the spring 5 is compressed more than a predetermined value, that is, before excessive tension is generated. The operating rod 22 activates the limit switch 20a. As a result, the motor 18 is reversed, the screw rod 15 is reversed, and the cylindrical casing 1 is pushed outward (rightward in FIG. 1) from the outer casing 3, and the operation rod 22 activates the home position limit switch 21. Controlled to stop at position and return to normal tension. The rate of tension change can be freely adjusted by the positions of the limit switches 19a and 20a. The limit switches 19b and 20b are reserved, and the starting position of the motor 18 can be changed by selection with the limit switches 19a and 20a.

  The limit switches 24a and 24b are for detecting the movement limit of the cylindrical casing 1, and when the cylindrical casing 1 moves, the relative movement distance from the hollow rod 2 does not reach a predetermined value and the limit switches 19a and 20a do not operate. Further, the limit switches 24a and 24b are operated by the end plate 8 to stop the rotation of the motor.

  This invention absorbs changes in sag tension due to expansion and contraction due to temperature changes of train lines (suspended lines, auxiliary suspended lines, trolley lines), elastic elongation due to creep and trolley line wear, and inclination of the support over time. This is effective when applied to a tension balancer for keeping the tension of the train line constant.

It is a vertical front view which shows the tension balancer for overhead wires of this invention. It is the top view which notched a part which shows the tension balancer for overhead wires of this invention. It is a side view which shows the tension balancer for overhead wires of this invention. It is IV-IV sectional drawing in FIG. It is a partial vertical front view which shows the tension balancer for overhead wires of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylindrical casing 2 Hollow rod 3 Outer casing 4 Pull handle 5 Coil spring 6 Outward flange 7 Inward flange 8 End plate 9 Sliding member 10 Side wall 11 Roller 12 Ball nut 13 End plate 14 Pull plate 15 Screw rod 16 Gear box 17 Reduction gear 18 Motor 19a Limit switch 19b Limit switch 20a Limit switch 20b Limit switch 21 Limit switch 22 Operating rod 23 Mounting rod 24a Limit switch 24b Limit switch 25 Mounting rod

Claims (3)

A cylindrical casing connected to the support so as to keep the tension of the overhead wire constant, and a hollow rod member that is received in the casing so as to be able to protrude and appear coaxially and connected to the overhead wire. And an overhead wire tension balancer having a coil spring coaxially interposed between the casing and the hollow rod member so as to elastically bias the hollow rod member in the immersion direction,
An outer casing that is interposed between the cylindrical casing and the support member and receives the cylindrical casing so as to be able to appear and disappear in the axial direction;
It is interposed between the outer casing and the cylindrical casing, and is screwed together so that the relative displacement in the axial direction between the outer casing and the cylindrical casing is rotated through an end plate provided in the cylindrical casing. Screw rods and nuts to convert,
A plurality of cylindrical casings are supported inside the outer casing so as to surround the cylindrical casing, are in rolling contact with the outer periphery of the cylindrical casing, and the axis of the cylindrical casing matches the axis of the screw rod. A roller that supports
A motor fixed to the outer casing for rotationally driving a screw rod or nut rotatably supported by the outer casing to relatively displace the cylindrical casing and the hollow rod member in an axial direction;
A plurality of limit switch means interposed between the outer casing and the hollow rod member at predetermined intervals to detect a relative position in the axial direction of each other;
Based on the relative position information of the cylindrical casing and the hollow rod member detected by the position detecting means, the motor is rotated so as to always arrange the cylindrical casing and the hollow rod member at a predetermined relative position. And an overhead wire tension balancer. The nut is fixed to the cylindrical casing, and a screw rod screwed to the nut is rotatably supported on the outer casing,
2. The aerial system according to claim 1, wherein the screw rod is rotatably connected to a motor fixed to the outer casing so as to relatively displace the cylindrical casing and the inner member in the axial direction. Tension balancer for wire.   The position detecting means includes a limit switch attached to the cylindrical casing, and an operating rod having one end fixed to the inner member, and the operating rod is arranged to be able to start the limit switch. The overhead wire tension balancer according to claim 1.

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