pantograph

Abstract

To provide a pantograph PG provided with squeezing means 7, installed in an air flow passage 5, which adjusts a flow rate of compressed air that is supplied from a compression air source 4 to suppress a framework 2 from rapidly moving up and moving down, which makes the framework 2 move down as quickly as possible when the framework is broken, without arranging control means for performing control based on sensed pressure by pressure sensing means, even if the squeezing means 7 is installed therein.SOLUTION: A pantograph PG is provided with: a bypass air passage 9, connected to a compressed air source 4, through which compressed air is directly supplied to an air actuator 6 without passing through squeezing means 7; a breakage sensing passage 10, connected to the bypass air passage 9, whose inner pressure drops due to breakage of the pantograph; and a switching valve 11 through which the compressed air source 4 is communicated with the air actuator 6 through the bypass air passage 9, when the inner pressure of the breakage sensing passage 10 drops.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pantograph in which a freely elevatable frame supporting a current collector shoe is raised by a mechanical biasing force such as a coil spring. [Background technology]

[0002] Conventionally, a pantograph of this type is known that includes the above-mentioned frame, a freely rotatable pivot shaft to which the frame is connected, a spring that generates a biasing force that raises the frame, an air actuator that is connected to a compressed air source via an air flow path and that applies a pressing force to the pivot shaft that resists the biasing force of the spring, thereby lowering the frame, and a throttle means that is interposed in the air flow path and adjusts the flow rate of compressed air supplied from the compressed air source to suppress sudden raising and lowering of the frame (see, for example, Patent Document 1).

[0003] The pantograph described in Patent Document 1 also includes a pressure detection means for detecting the pressure of an air chamber formed in the current collecting shoe to which compressed air is supplied from a compressed air source, a current breaker for controlling the connection and disconnection between the pantograph and a power converter installed on the train, and a control means for controlling the operation of the current breaker and the supply and discharge of compressed air to a cylinder provided as an air actuator based on the pressure in the pressurizing chamber detected by the pressure detection means.In the pantograph described in Patent Document 1, if the current collecting shoe is damaged and compressed air leaks from the pressurizing chamber, causing the pressure in the pressurizing chamber to fall below a predetermined set pressure, which is a failure detection pressure, the pressure detection means will be turned off and the control means will open the current breaker and discharge compressed air from inside the cylinder. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-11784 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the pantograph described in Patent Document 1, a throttle means is provided in the air flow path that supplies compressed air from the compressed air source to the air actuator, so when the current collector shoe is damaged, the speed at which the frame descends is the same as the normal speed, and the current collector shoe does not immediately detach from the overhead wire. Therefore, the above-mentioned control means is indispensable for the pantograph described in Patent Document 1.

[0006] In view of the above, an object of the present invention is to provide a pantograph that can lower the frame as much as possible in the event of damage, even if a throttling means is provided in the air flow path connected to a compressed air source, without providing a control means that performs control based on the pressure detected by the pressure detection means. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a current collector shoe including a frame that can be raised and lowered to support the current collector shoe, a rotatable pivot shaft to which the frame is connected, a spring that generates a biasing force to raise the frame, and an air actuator that is connected to a compressed air source via an air flow path and applies a pressing force to the pivot shaft against the biasing force of the spring to lower the frame. The aforementioned It is installed in the air flow path, The aforementioned a throttle means for adjusting the flow rate of compressed air supplied from a compressed air source to suppress abrupt ascent and descent of the frame, The aforementioned Connected to a compressed air source, The aforementioned Compressed air The aforementioned Without using a throttling means The aforementioned a bypass air flow path that directly supplies air to the air actuator; and a bypass air flow path connected to the bypass air flow path. Applicable A damage detection channel where the internal pressure drops as the pantograph breaks, and when the internal pressure of this damage detection channel drops, The aforementioned Compressed air source , the above Through the bypass air passage The aforementioned The present invention is characterized in that a switching valve is provided to communicate with an air actuator.

[0008] According to the present invention, when the internal pressure of the breakage detection flow path drops, the compressed air source is switched off by the switching valve. , Ba The frame is connected to the air actuator via the bypass air flow path, and compressed air is supplied to the air actuator without passing through the throttling means. Therefore, in the event of damage to the pantograph, the frame descends as quickly as possible, minimizing the extent of damage to the overhead wire. Therefore, even if a throttling means is provided in the air flow path connected to the compressed air source, there is no need to provide a control means for controlling the air based on the pressure detected by the pressure detection means, simplifying the structure of the pantograph. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing an embodiment of a pantograph of the present invention. [Figure 2] 2 is a schematic diagram showing the pantograph shown in FIG. 1 in a normal state. [Figure 3] 2 is a schematic diagram showing the pantograph shown in FIG. 1 when broken; DETAILED DESCRIPTION OF THE INVENTION

[0010] A pantograph PG, one embodiment of the present invention, will be described with reference to Figure 1. The pantograph PG includes a frame 2 that can be raised and lowered and supports a current collector shoe 1, and a pivot shaft 3 to which the frame 2 is connected and that can be rotated. The pantograph PG also includes a spring (not shown), such as a coil spring, that generates a biasing force to raise the frame 2, and an air actuator 6 that is connected to a compressed air source 4 via an air flow path 5 and applies a pressing force to the pivot shaft 3 against the biasing force of the spring, thereby lowering the frame 2. The pantograph PG also includes a throttle means 7 that is disposed in the air flow path 5 and that adjusts the flow rate of compressed air supplied from the compressed air source 4 to prevent the frame 2 from rising or falling suddenly.

[0011] Specifically, the pivot shaft 3 is provided on an underframe 8 that is installed on the roof of the train car body. The framework 2 is composed of an upper frame 21 that supports the current collector shoe 1 at one end, and a lower frame 22 that supports the other end of the upper frame 21 at one end and has the other end connected to the pivot shaft 3. The framework 2 is generally provided with a bridge support 23 that helps support the current collector shoe 1 at one end of the upper frame 21, a balancing link 24 that connects the bridge support 23 to the other end of the lower frame 22 to keep the elevation angle of the current collector shoe 1 horizontal, and a balancing link 25 that connects the other end of the upper frame 21 to the underframe 8.

[0012] Furthermore, the air actuator 6 is composed of a hollow cylinder 61 fixed to the frame 8, and a piston rod 62 that is pushed out toward the rotary shaft 3 when compressed air is supplied to the inside of the cylinder 61, and is retracted in the opposite direction from the rotary shaft 3 when compressed air is discharged from the inside of the cylinder 61. The rotary shaft 3 is provided with a lever 31 that comes into contact with the tip of the piston rod 62 when it is pushed out, and the pressing force of the compressed air acts against the biasing force of a spring. When the piston rod 62 is pushed out from the cylinder 61 toward the rotary shaft 3, it comes into contact with the lever 31, and the pressing force of the compressed air acts on the rotary shaft 3, suppressing the biasing force of the spring.

[0013] Furthermore, the throttle means 7 is provided with a fixed throttle 71 for adjusting the descending speed of the framework 2, which is disposed in a portion of the air flow path 5 located on the upstream side, and a speed controller 72 for adjusting the ascending speed of the framework 2, which is disposed in a portion of the air flow path 5 located downstream of the fixed throttle 71. The speed controller 72 is disposed in the air flow path 5 and is composed of a check valve 72a that allows compressed air to only flow into the air flow path 5, and a variable orifice 72b that is connected to the air flow path 5 in parallel with the check valve 72a.

[0014] The pantograph PG is connected to a compressed air source 4 and has a bypass air flow path 9 that supplies compressed air directly to the air actuator 6 without passing through the throttling means 7, a damage detection flow path 10 that is connected to the bypass air flow path 9 and whose internal pressure decreases as the pantograph PG is damaged, and a breakage detection flow path 10 that detects the pressure drop in the damage detection flow path 10 when the internal pressure of the breakage detection flow path 10 decreases. , BaA switching valve 11 is provided to communicate with the air actuator 6 via the bypass air flow path 9.

[0015] Specifically, the damage detection flow path 10 branches off from a portion of the bypass air flow path 9 located upstream of the switching valve 11 and is connected to a compressed air supply unit 12, such as an air chamber, formed inside the current collector 1. The compressed air supply unit 12 is not limited to the air chamber, and may be any portion where compressed air leaks from the damage detection flow path 10 and reduces the internal pressure of the damage detection flow path 10 when the pantograph PG is damaged. Therefore, the position of the damage detection flow path 10 in the pantograph PG is not particularly limited as long as it is connected to the compressed air supply unit 12. Furthermore, a restrictor 13 is provided in the damage detection flow path 10 at a portion located closer to the portion where it branches off from the bypass air flow path 9 than the compressed air supply unit 12. The restrictor 13 reduces the amount of compressed air leaking from the damage detection flow path 10.

[0016] The bypass air flow path 9 branches off at a portion of the air flow path 5 located upstream of a fixed throttle 71, which is one of the throttle means 7, and is connected to a portion of the air flow path 5 located downstream of a speed controller 72. A solenoid valve 14 is provided in the upstream portion of the bypass air flow path 9, which switches between supplying, discharging, and stopping compressed air from the compressed air source 4 to the air actuator 6. A check valve 15 is also provided in the bypass air flow path 9, located downstream of the switching valve 11 and upstream of the portion where the bypass air flow path 9 is connected to the air flow path 5. The check valve 15 only allows compressed air to flow from the bypass air flow path 9 to the air actuator 6.

[0017] A solenoid valve 16 similar to the solenoid valve 14 provided in the bypass air flow path 9 is provided in the air flow path 5, at a location downstream of the branch point of the bypass air flow path 9 and upstream of the fixed throttle 71. A switching valve 17 is also provided in the air flow path 5, at a location downstream of the speed controller 72 and upstream of the connection point of the bypass air flow path 9 to the air flow path 5. The switching valve 17 switches between communication and cut-off between the air flow path 5 and the air actuator 6 depending on the internal pressure in the portion of the bypass air flow path 9 from the switching valve 11 to the check valve 15. A pilot valve such as an external pilot air operated valve is preferably used for the switching valves 11 and 17.

[0018] In the pantograph PG described above, the current collector shoe 1, frame 2, pivot shaft 3, air actuator 6, underframe 8, and the air flow path 5 located on the air actuator 6 side are installed on the roof of the train car body. On the other hand, the compressed air source 4, solenoid valves 14 and 16, and the air flow path 5 and bypass air flow path 9 located around them are not installed on the roof of the train car body. In contrast, the bypass air flow path 9 from the solenoid valve 14 to the check valve 15 and the air flow path 5 from the solenoid valve 16 to the connection of the bypass air flow path 9 can be installed not only on the roof of the train car body but also inside the car body. Therefore, by incorporating or replacing the bypass air flow path 9 from the solenoid valve 14 to the check valve 15 and the air flow path 5 from the solenoid valve 16 to the connection of the bypass air flow path 9 into or replacing the above-mentioned vehicle accessories with an existing pantograph, the pantograph PG of this embodiment can be improved.

[0019] Also, reference numeral 18 shown in FIG. 1 denotes a hook means for holding the lowered framework 2 in a folded state.

[0020] In this pantograph PG, as shown in FIG. 2, when the frame 2 is raised and the current collector shoe 1 is brought into contact with the overhead wire, the solenoid valve 16 is demagnetized, and the exhaust port of the solenoid valve 16 is connected to the air actuator 6 via the air flow path 5. Therefore, compressed air from the air supply source 4 is not supplied to the air flow path 5. Therefore, the switching valves 11 and 17 connect the air actuator 6 to the exhaust ports of the solenoid valves 14 and 16. Then, the folding of the frame 2 by the hook means 18 is released, and the biasing force of the spring acts on the rotating shaft 3, causing the frame 2 to rise. At this time, as the rotating shaft 3 rotates in the direction to raise the frame 2, the lever 31 attached to the rotating shaft 3 comes into contact with the tip of the piston rod 62 of the air actuator 6 and presses the piston rod 62 toward the opposite side from the rotating shaft 3. Air remains inside the cylinder 61 of the air actuator 6 and the air flow path 5. Because fixed throttle 71 is provided in air flow path 5, this residual air is compressed inside air flow path 5 as framework 2 rises. As a result, the pressure of the compressed residual air increases and is adjusted by variable orifice 72b, generating a pushing force in the direction of pushing piston rod 62 out. This pushing force acts to push back lever 31. Therefore, the biasing force of the spring acting on rotary shaft 3 is weakened by the above pushing force, and framework 2 rises gently. Note that the compressed residual air does not flow into bypass air flow path 9 because check valve 15 is provided.

[0021] To release the current collector shoe 1 from contact with the overhead wire, the solenoid valve 16 is energized, and the solenoid valve's air inlet port connects the compressed air source 4 to the air actuator 6 via the air flow path 5. The switching valve 17 connects the air actuator 6 to the solenoid valve's air inlet port. Compressed air from the compressed air source 4 passes through a fixed orifice 71 and, thanks to the check valve 72, flows through the variable orifice 72b and down the air flow path 5 toward the air actuator 6. As a result, compressed air from the compressed air source 4 is quickly supplied to the inside of the cylinder 61 of the air actuator 6, pressurizing the inside of the cylinder 61. This generates a pressing force on the air actuator 6 in a direction pushing the piston rod 62 toward the pivot shaft 3. This pressing force is set to a magnitude sufficient to offset the spring's biasing force. Therefore, the pushed-out piston rod 62 pushes the lever 31 back in the opposite direction from when the frame 2 was raised. As a result, the pressing force generated by the air actuator 6 acts on the rotating shaft 3, causing the framework 2 to descend. However, since the compressed air supplied to the air flow path 5 passes through the fixed throttle 71, the framework 2 does not suddenly descend, but rather descends gently in the same way as it rose.

[0022] In the pantograph PG, the spring force raises the frame 2, bringing the current collector shoe 1 into contact with the overhead wires. While the train is running, including during operating hours when the train is stopped or traveling to a stopping position, the solenoid valve 16 is de-energized, halting the supply of compressed air from the compressed air source 4 to the air actuator 6 via the air flow path 5. Meanwhile, the solenoid valve 14 is energized, causing compressed air from the compressed air source 4 to flow into the bypass air flow path 9. Some of the compressed air flowing into the bypass air flow path 9 is supplied to the compressed air supply unit 12 via the damage detection flow path 10. In this state, if the current collector shoe 1 of the pantograph PG is not damaged and the internal pressure of the damage detection flow path 10 is maintained at a predetermined pressure, the switching valve 11 cuts off communication between the bypass air flow path 9 and the air actuator 6. Therefore, compressed air from the compressed air source 4 is not supplied to the air actuator 6, and the frame 2 remains raised. Since no compressed air flows into the bypass air flow path 9 , the switching valve 17 keeps the exhaust port of the solenoid valve 16 and the air actuator 6 in communication.

[0023] On the other hand, if the pantograph PG is damaged, the compressed air supplied to the compressed air supply unit 12 leaks, and the internal pressure of the damage detection channel 10 drops, as shown in FIG. 3 . The switching valve 11 switches to connect the bypass air channel 9 to the air actuator 6. Furthermore, the increase in the internal pressure of the bypass air channel 9, located downstream of the switching valve 11, causes the switching valve 17 to switch to block the air channel 5. In conjunction with the presence of the check valve 15, the compressed air supplied from the compressed air source 4 through the bypass air channel 9 is directly supplied to the air actuator 6 because no throttle means 7 is provided in the bypass air channel 9. Therefore, the rate at which the internal pressure of the cylinder 61 of the air actuator 6 rises increases, and accordingly, the pushing speed at which the piston rod 62 is pushed toward the rotating shaft 3 also increases. As a result, the rotation speed of the rotating shaft 3 in the direction of lowering the frame 2 due to contact with the lever 31 also increases, causing the frame 2 to descend faster than the normal descent speed. In this way, in the case of damage to the pantograph PG, the framework 2 descends as much as possible without the need for a control means that performs control based on the pressure detected by the pressure detection means. This makes it possible to minimize the extent of damage to the overhead wire. Furthermore, by omitting the control means, the configuration of the pantograph PG is simplified.

[0024] Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited thereto. For example, the current collector 1, frame 2, and air actuator 6 may have a variety of configurations and structures. While the single-arm frame 2 is illustrated, it may also have a diamond shape. Furthermore, a mechanical biasing force generating means, such as a coil spring, that generates a biasing force that pulls the piston rod 62 toward the opposite side of the pivot shaft 3 may be installed inside the cylinder 61 of the air actuator 6. Furthermore, the spring that raises the frame 2 is not limited to a coil spring, as long as it generates a mechanical biasing force. [Explanation of symbols]

[0025] PG...pantograph, 1...collector boat, 2...frame, 3...rotating shaft, 4...compressed air source, 5...air flow path, 6...air actuator, 7...throttling means, 9...bypass air flow path, 10...breakage detection flow path, 11...switching valve.

Claims

[Claim 1] A pantograph comprising: a liftable frame supporting a current collector shoe; a rotatable pivot shaft connected to the frame; a spring generating an urging force for raising the frame; an air actuator connected to a compressed air source via an air flow path and applying a pressing force to the pivot shaft against the urging force of the spring to lower the frame; and throttle means interposed in the air flow path and regulating the flow rate of compressed air supplied from the compressed air source to suppress a sudden rise and fall of the frame, a bypass air flow path connected to the compressed air source for supplying the compressed air directly to the air actuator without passing through the throttling means; a damage detection flow path connected to the bypass air flow path, the internal pressure of which decreases as the pantograph is damaged; and a switching valve for connecting the compressed air source to the air actuator via the bypass air flow path when the internal pressure of the damage detection flow path decreases.

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