JP2008075818A - Pull gas spring and pull gas spring unit for railway wires - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize the unit by shortening the balancer length without enlarging the diameter of an outer casing unnecessarily. <P>SOLUTION: The unit is furnished with the middle side plate 70 which blocks an opening of a fixed side of an outer casing 40 and an opening of an input side of a bellows outer cylinder 50, the piston cylinder 32 which is accommodated in the outer cylinder 40, the seal part side plate 60 which blocks the outer cylinder 40 and the opening of the piston cylinder 32, the rod 20 which the input side end is arranged for the input side to the seal part side plate 60 and the fixed side end is arranged in the piston cylinder 32, a piston 23 which divides the inside of the piston cylinder 32 into a cylinder oil chamber 27 and a low pressure gas chamber, the bellows 51 which is accommodated in the bellows outer casing 50 and makes a bellows oil chamber 54 and a bellows high pressure gas chamber and the hydraulic fluid communication channel 74 which guides the hydraulic fluid in between the cylinder-oil chamber 27 and the bellows oil chamber 54. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tension gas spring device used for tension adjustment of railway overhead wires, industrial machines, building members, and the like, and a tension gas spring device for railway overhead wires, and more particularly to one that can be miniaturized.

A tension gas spring device is used to adjust the tension of railway overhead lines, industrial machines, building members, and the like. As a tension gas spring device, for example, a bellows type gas spring has been proposed in which a tensile force is obtained by a structure in which a bellows is attached to a gas spring attachment side plate and a gas chamber is provided in the bellows (see, for example, Patent Document 1). In general, the gas spring device is small, has a high initial load, and can have a low spring constant as compared with a coil spring device. In addition, a structure in which a high pressure gas chamber is provided outside the bellows and a cylinder is provided inside the bellows has been proposed (see, for example, Patent Document 1).
JP 2001-20987 A

  The tension gas spring device described above has the following problems. That is, in the structure in which the bellows is attached to the gas spring attachment side plate and the gas chamber is provided in the bellows, the cylinder and the bellows are arranged in series, so that the bellows is secured in order to secure a gas chamber corresponding to the required spring constant. As a result, there is a problem that the total length of the gas spring becomes long. Furthermore, since there is no low-pressure gas sealing part outside, after the low-pressure gas is sealed in the cylinder, the cylinder has to be assembled to the outer cylinder, resulting in a complicated manufacturing process.

  On the other hand, in the structure in which the outside of the bellows is a high pressure gas chamber and the cylinder is provided in the bellows, the total length is short, but the tip of the cylinder cannot be fixed. There was a problem of lack.

  Accordingly, an object of the present invention is to provide a tension gas spring device capable of shortening the overall length and improving the permanent reliability against the lateral vibration input.

  In order to solve the above-described problems and achieve the object, the tension gas spring device and the railway gas tension gas spring device of the present invention are configured as follows.

  In a tension gas spring device arranged between an input side to which a tensile force is inputted and a fixed side, an outer cylinder arranged with an axis connecting the input side and the fixed side as its axis, and the axis A bellows outer cylinder disposed on the fixed side of the outer cylinder, an opening on the fixed side of the outer cylinder, and an intermediate plate that closes the input-side opening of the bellows outer cylinder, A piston cylinder that is housed in an outer cylinder and that is arranged with the axis as its axis and whose fixed side opening is closed by the middle plate, and an input side opening of the outer cylinder and the piston cylinder And a seal part side plate having an opening hole in the center part, and the axis line is disposed as an axis of the seal part side plate so as to be slidable in the opening hole of the seal part side plate. Input side, fixed side end against the part side plate A rod arranged inside the piston cylinder, a bellows side plate that closes the fixed side of the bellows outer cylinder, and a fixed side end portion side of the rod, and the input side in the piston cylinder is fixed to a cylinder oil chamber A piston that divides the side into a low-pressure gas chamber, and is housed in the bellows outer cylinder, the input side end is fixed to the middle plate, the fixed side end is closed by a partition member, and the inside is a bellows oil chamber, A bellows having an external bellows high-pressure gas chamber, a hydraulic fluid communication channel for communicating hydraulic fluid between the cylinder oil chamber and the bellows oil chamber, an inner side of the outer cylinder, and an outer side of the piston cylinder And a high-pressure gas communication channel for communicating the high-pressure gas between the high-pressure gas chamber in the outer cylinder and the bellows high-pressure gas chamber.

  According to the present invention, it is possible to reduce the size by reducing the balancer length without increasing the outer cylinder diameter more than necessary.

  FIG. 1 is a cross-sectional view showing the structure of a tension gas spring device 10 according to an embodiment of the present invention. The tension gas spring device 10 has a structure (outer gas structure) in which a high-pressure gas chamber is provided outside the bellows 51. In FIG. 1, D indicates a utility pole, K indicates an overhead wire, S indicates a support bar, and Q indicates a mounting bracket.

  The tension gas spring device 10 includes a rod 20, an inner cylinder 30, an outer cylinder 40, and a bellows outer cylinder 50 that are arranged coaxially with the rod 20.

  The rod 20 has an end 21 on the left side in FIG. 1 attached to the overhead line K, and an end 22 on the right side in FIG. 1 disposed in a piston cylinder 32 described later of the inner cylinder 30. A piston 23 is attached to the outer peripheral portion of the end portion 22 so as to reciprocate on the inner peripheral surface of the piston cylinder 32. On the outer periphery of the piston 23, a piston part seal 24 that seals working oil and low-pressure gas and a piston bearing 25 that guides the piston 23 are provided. Thereby, a low-pressure gas chamber 26 is formed in the space on the right side of the piston 23 in FIG. 1, and a cylinder oil chamber 27 is formed in the space on the left side. In FIG. 1, reference numeral 28 denotes a hollow part constituting a part of the low-pressure gas chamber, and 29 denotes a rod cover.

  The inner cylinder 30 includes a cylindrical cylinder body 31 and a piston cylinder 32 that is coaxially arranged with a gap formed inside the cylinder body 31. A passage 33 through which the working oil flows is formed in a gap between the inner periphery of the cylinder body 31 and the outer periphery of the piston cylinder 32, and is located at the left end of the piston cylinder 32 in FIG. A communication hole 34 for communicating the inside of the piston cylinder 32 and the flow path 33 is formed. The cylinder oil chamber 27 and a bellows oil chamber 54 described later communicate with each other through the flow path 33. The opening on the right side in FIG. 1 of the piston cylinder 32 is closed by an intermediate plate 70 described later.

  An opening on the left side in FIG. 1 of the outer cylinder 40 is closed with a seal side plate 60, and an opening on the right side in FIG. An outer cylinder high-pressure gas chamber 41 is formed between the outer side of the inner cylinder 30 and the inner side of the outer cylinder 40. In FIG. 1, reference numeral 42 denotes a support bar joint.

  An opening on the left side of the bellows outer cylinder 50 in FIG. 1 is closed by the middle plate 70, and an opening on the right side in FIG. 1 is closed by the bellows side plate 80. A bellows 51 made of a thin metal material is disposed inside the bellows outer cylinder 50, and the left end in FIG. 1 is closed by an inner side plate 70, the right end is closed by a partition member 52, and a guide bellows 53 is disposed on the outer periphery of the partition member 52. It is attached. Inside the bellows 51, a bellows oil chamber 54 in which operating oil is accommodated is formed. The guide bellows 53 is configured to slide on the inner peripheral surface of the bellows outer cylinder 50 so as to reciprocate. The bellows oil chamber 54 communicates with the flow path 33 via a through-passage 74 described later. A high-pressure gas chamber 55 is formed inside the bellows outer cylinder 50 and outside the bellows 51.

  The seal part side plate 60 includes an opening hole 61 for allowing the rod 20 to reciprocate, a dust seal 62 for sealing the working oil provided facing the inner periphery of the opening hole 61, and a rod part for sealing the working oil. A seal 63 and a rod bearing 64 for guiding the rod 20 are provided.

  The middle plate 70 is provided in the disc-shaped plate body 71, the low pressure gas sealing hole 72 for sealing the low pressure gas in the piston cylinder 32, and the low pressure gas sealing hole 72. A low-pressure gas sealing plug 73, a through-passage 74 for allowing operating oil to flow, an oil injection hole 75 connected to the through-passage 74, an oil injection plug 76 for closing the oil injection hole 75, and an outer cylinder A high-pressure gas communication hole 77 that allows high-pressure gas to flow between the internal high-pressure gas chamber 41 and the high-pressure gas chamber 55 is provided.

  The bellows side plate 80 includes a disc-shaped plate main body 81, a high-pressure gas sealing hole 82 provided through the plate main body 81, a high-pressure gas sealing plug 83 for closing the high-pressure gas sealing hole 82, 1 and a joint 84 that is swingably supported with respect to the mounting bracket Q.

  Low-pressure gas is injected into the tension gas spring device 10 configured as described above from the low-pressure gas sealing hole 72 of the middle side plate, and sealed with a low-pressure gas sealing plug 73. Alternatively, the atmosphere may be enclosed or communicated with the atmosphere. The gas pressure in the low-pressure gas chamber 26 is preferably a low pressure of about atmospheric pressure. By providing the hollow portion 28 constituting a part of the low-pressure gas chamber 26 in the rod 20, the volume of the low-pressure gas chamber can be increased, and the rod can be expanded and contracted. The accompanying increase in the low pressure gas pressure can be kept low.

  Further, high pressure gas is injected from the high pressure gas sealing hole 82 and sealed with a high pressure gas sealing plug 83. The high-pressure gas encloses a dry inert gas such as nitrogen gas at a pressure that satisfies the required load and the required spring constant. Part of oil may be injected into the outer cylinder high-pressure gas chamber 41 and the high-pressure gas chamber 55 for adjusting the spring constant.

  The hydraulic oil injected into the cylinder oil chamber 27 and the bellows oil chamber 54 is preferably a mineral oil having excellent low temperature fluidity.

  The tension gas spring device 10 is attached to the utility pole D by the mounting bracket Q, and the weight gas spring device 10 is attached to the utility pole D so that the weight is received by the support rod S.

  A support rod joint 42 is assembled to the lower portion of the outer cylinder 40, the inner side plate 70, or the bellows outer cylinder 50, and the support rod S from the utility pole D is attached to the support rod joint 42 so that the overhead wire K and the rod 20 are parallel to each other. The support bar S receives the weight of the gas spring device 10.

  In the tension gas spring device 10 configured in this way, the bellows 51 has a thin plate thickness and has no pressure resistance itself and can expand and contract. Therefore, the pressure in the bellows oil chamber 54 is sealed in the high-pressure gas chamber 55. It becomes equivalent to pressure. Accordingly, the tension is always applied to the overhead wire K by the piston 23 via the rod 20.

  When the temperature decreases and the overhead line K contracts, the rod 20 moves to the left in FIG. 1 and the piston 23 expands the low-pressure gas. At this time, the operating oil moves from the cylinder oil chamber 27 into the bellows oil chamber 54, and the partition member 52 moves to the right in FIG.

  When the temperature rises and the overhead line K is extended, the piston 23 is applied with a force in the right direction in FIG. 1 due to the action of the low-pressure gas, and the operating oil moves from the bellows oil chamber 54 into the cylinder oil chamber 27. 1 moves to the left in FIG. 1, returns to the original position, and applies a constant tension to the overhead line K.

The high-pressure gas sealed in the high-pressure gas chamber 55 is {(P × V) / T} = constant (1), where P is the pressure, V is the volume, and T is the absolute temperature.
It becomes the relationship. As a result, the pressure P or the volume V changes due to a change in temperature, so the expansion / contraction amount of the rod 20 obtained from the volume change of the high-pressure gas chamber 55 due to the temperature change and the extension / contraction amount of the overhead wire K due to the temperature change are set to be the same. By doing so, the tension of the overhead wire K can be made constant regardless of the temperature change.

The conditions for making the tension constant regardless of the temperature change are as follows: the volume V of the gas sealed in the high-pressure gas chamber 55 is A (piston cross-sectional area−rod cross-sectional area), A is the overhead wire length, and L is the linear expansion coefficient. If α and absolute temperature are T,
V = A × L × α × T (2)
The value obtained by. However, as a rough design, it is assumed that the load due to the pressure of the low-pressure gas and the expansion of oil can be ignored.

  On the other hand, stress is generated in the peaks and valleys of the bellows 51 by expansion and contraction. The number of times this stress and expansion / contraction can be repeated is determined by a durability test. The generated stress is determined by the bellows shape and the number of bellows peaks. Therefore, the required number of bellows is determined from the number of use durability.

  As described above, according to the tension gas spring device 10 according to the present embodiment, the gas satisfying the volume V of the gas sealed in the high pressure gas chamber 55 is formed by configuring the high pressure gas chamber 55 outside the bellows 51. The chamber volume can be secured regardless of the number of bellows. Further, by forming the space between the inner cylinder 30 and the outer cylinder 40 or the space between the outer cylinder 40 and the piston cylinder 32 as the high-pressure gas chamber 55, the outer cylinder diameter can be configured without increasing more than necessary. .

  In addition, in the tension gas spring using the structure (internal gas structure) in which the high-pressure gas chamber is provided in the bellows, the high-pressure gas chamber has a volume in the bellows gas chamber determined by determining the required number of bellows from the number of use durability described above. The required gas chamber volume with a constant tension obtained by the equation of the volume V of the gas sealed in cannot be secured. For this reason, it is necessary to secure the number of bellows more than the number of bellows obtained from the durability condition, and the balancer length becomes long.

  Specifically, the overhead wire tension is 3500 kgf, the overhead wire length is 800 m, the overhead wire temperature elongation coefficient is 0.0000142 / ° C, the rod diameter is φ50 mm, the piston diameter is φ75 mm, the bellows effective diameter is φ74.5 mm, and the bellows allowance for 10,000 times The required bellows length in the inner gas structure and the outer gas structure when the displacement is 2.53 mm / peak, the bellows minimum pitch is 2.45 mm / peak, and the bellows end length is 4.5 mm is shown.

The gas volume (at 15 ° C.) V for which the tension is constant is obtained as V = 8025 cm ³ . In the inner gas structure, when the bellows length is obtained from the gas volume, the bellows length is 1842 mm. When the bellows length is obtained from the durability in the outer gas structure like the tension gas spring device 10 according to the present embodiment, the bellows length is 387 mm, and the difference from the inner gas structure is 1454 mm. The change in overhead wire length with respect to a temperature change of 30 ° C. is 304.8 mm, and it can be seen that the outer gas structure can be significantly shortened compared to this value.

  As described above, according to the tension gas spring device 10 according to the present embodiment, the overall length can be shortened and the permanent reliability against the lateral vibration input can be increased. Further, it is possible to reduce the size by shortening the balancer length without increasing the outer cylinder diameter more than necessary.

  In addition, about the tension | pulling gas spring apparatus 10, you may change a part of structure mentioned above. For example, the high-pressure gas sealing plug may be provided on the inner side plate, the outer cylinder, and the seal portion side plate. The oil injection plug may be provided on the seal portion side plate. Further, a hydraulic pressure detector may be attached to the oil filler plug so that the tensile force can be monitored. Moreover, you may use a suspension bar instead of a support bar (refer FIG. 2).

  FIG. 2 is a cross-sectional view showing the configuration of a tension gas spring device 10A according to the second embodiment of the present invention. 2 that are the same as those in FIG. 1 are assigned the same reference numerals, and detailed descriptions thereof are omitted. Note that R in FIG. 2 indicates a hanging rod.

  In the tension gas spring device 10A according to the present embodiment, a bottomed cylindrical stay 90 is provided inside the bellows oil chamber 54 and on the right side in FIG. 2 of the middle plate 70, and the center of the stay bottom plate 91 of the stay 90 is provided. A stay oil passage 92 is formed in the bottom. A stay oil chamber 93 is formed inside the stay 90. The bellows oil chamber 54 communicates with the stay oil passage 92.

  Further, an oil pipe 100 that connects the cylinder oil chamber and the middle side plate oil flow path is provided instead of the cylinder main body 31 to communicate between the cylinder oil chamber 27 and the bellows oil chamber 54.

  A self-sealing member 56 made of rubber is attached to the surface of the partition member 52 on the stay 90 side. When the hydraulic oil in the bellows inner oil chamber 54 is reduced to a specified amount, the self-sealing member 56 comes into contact with the stay bottom plate 91 and has a function of confining the hydraulic oil between the bellows 51 and the stay 90 and the self-sealing member 56. Have.

  A suspension rod joint 43 is attached to the upper portion of the outer cylinder 40, the middle plate 70, or the bellows outer cylinder 50, and the suspension rod R from the utility pole D is attached to the suspension rod joint 43 so that the overhead wire K and the rod 20 are parallel to each other. The weight of the tension gas spring 10A is received by the suspension rod suspension rod R.

  The tension gas spring device 10A configured in this way also operates in the same manner as the tension gas spring device 10 described above. The bellows 51 does not have a length less than the specified length by the stay 90, and since no differential pressure is applied to the bellows 51, even if the operating oil is insufficient to the specified amount due to leakage of the operating oil. The damage of the bellows 51 can be prevented. Moreover, the length of the bellows 51 can be defined by the length of the stay 90 at the time of gas filling, and the high pressure gas filling volume can be filled accurately.

  By receiving the weight of the tension gas spring with the suspension rod, the swinging of the overhead wire and the lateral load on the rod 20 from the weight of the tension gas spring can be reduced, so that the sliding resistance of the rod 20 can be reduced and smooth operation can be obtained. . Furthermore, oil leakage from the seal can be prevented and high durability can be secured.

  As described above, according to the tension gas spring device 10A according to the present embodiment, the same effects as those of the tension gas spring device 10 described above can be obtained, and the durability and size can be reduced.

  In addition, about the tension | pulling gas spring apparatus 10A, you may change a part of structure mentioned above. For example, the outer cylinder 40 of the tension gas spring, the bellows outer cylinder 50, the seal part side plate 60, and the outside of the bellows side plate 80 are wrapped with a strong outer cylinder cover, and a support rod joint or a suspension is hung on the outer surface of the outer cylinder cover cylinder. A structure may be adopted in which a rod joint is assembled and a fitting joint is assembled on the outer surface of the outer cylinder cover side surface on the bellows side plate side to protect the tension gas spring. Moreover, you may use a support bar instead of a suspension bar (refer FIG. 1).

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

The longitudinal cross-sectional view which shows the tension | pulling gas spring apparatus which concerns on the 1st Embodiment of this invention. The longitudinal cross-sectional view which shows the tension | pulling gas spring apparatus which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10,10A ... tension | pulling gas spring apparatus, 20 ... rod, 23 ... piston, 30 ... inner cylinder, 32 ... piston cylinder, 40 ... outer cylinder, 50 ... bellows outer cylinder, 51 ... bellows, 60 ... seal part side plate, 70 ... middle plate, 80 ... bellows side plate, 90 ... stay.

Claims (6)

In the tension gas spring device arranged between the input side where the tensile force is inputted and the fixed side,
An outer cylinder arranged with its axis connecting the input side and the fixed side as its axis;
A bellows outer cylinder disposed on the fixed side of the outer cylinder, the axial line as the axis,
An opening on the fixed side of the outer cylinder and an inner side plate for closing the opening on the input side of the bellows outer cylinder;
A piston cylinder that is housed in the outer cylinder, is disposed with the axis as its axis, and a fixed-side opening is closed by the middle plate;
A seal side plate that closes the opening on the input side of the outer cylinder and the piston cylinder and has an opening in the center;
The seal part side plate is slidable in the opening hole, and the axis line is arranged as its axis, the input side end is the input side with respect to the seal part side plate, and the fixed side end is inside the piston cylinder. A rod arranged in
A bellows side plate for closing the fixed side of the bellows outer cylinder;
A piston provided on the fixed side end of the rod, and dividing the input side in the piston cylinder into a cylinder oil chamber and the fixed side into a low-pressure gas chamber;
A bellows which is accommodated in the bellows outer cylinder, the input side end is fixed to the middle plate, the fixed side end is closed by a partition member, the inside is a bellows oil chamber, and the outside is a bellows high pressure gas chamber; ,
A hydraulic fluid communication channel for communicating hydraulic fluid between the cylinder oil chamber and the bellows oil chamber;
A high-pressure gas communication channel that communicates high-pressure gas between the high-pressure gas chamber in the outer cylinder and the bellows high-pressure gas chamber provided between the inner side of the outer cylinder and the outer side of the piston cylinder; A tension gas spring device. Inside the bellows is provided a cylindrical stay with a bottom plate on the fixed side,
A stay oil passage is provided on the bottom plate of the stay,
The tension gas spring device according to claim 1, wherein the partition member is provided with a seal member that closes the stay oil passage when the bellows contracts.   3. The tension gas spring device according to claim 1, wherein the hydraulic oil communication channel is provided inside a high-pressure gas chamber in the outer cylinder. An inner cylinder is provided coaxially between the piston cylinder and the outer cylinder,
The hydraulic fluid communication channel is a space between the piston cylinder and the inner cylinder,
The tension gas spring device according to claim 1 or 2, wherein the high pressure gas chamber in the outer cylinder is a space between the inner cylinder and the outer cylinder.   The tension gas spring device according to any one of claims 1 to 4, wherein a low-pressure gas sealing plug for sealing the low-pressure gas into the low-pressure gas chamber is provided in the middle side plate portion. The input side end of the rod is connected to the railway overhead line,
The tension gas spring device for a railway overhead wire according to any one of claims 1 to 5, wherein the bellows side plate is connected to an attachment portion connected to the ground.

Images