# US 2014/0196628 A1 · Railcar damping device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0196628 A1 - Document ID: US20140196628A1 - Status: Published application - Kind: A1 - Application number: 14/127,916 - Filed: 2012-06-19 - Published: 2014-07-17 - Earliest claimed: 2011-06-20 - Assignees: Kayaba Industry Co., Ltd. - Inventors: Takayuki Ogawa; Jun Aoki; Masaru Uchida; Chie Yabuki - Web page: https://patentgrep.com/patent/US20140196628A1 ## CPC - B61F 5/24: Means for damping or minimising the canting, skewing, pitching, or plunging movements of the underframes - B61F 5/245: {by active damping, i.e. with means to vary the damping characteristics in accordance with track or vehicle induced reactions, especially in high speed mode} - F15B 7/006: {Rotary pump input} - F15B 2211/7053: Double-acting output members - F15B 2211/785: Compensation of the difference in flow rate in closed fluid circuits using differential actuators - B61F: RAIL VEHICLE SUSPENSIONS, e.g. UNDERFRAMES, BOGIES OR ARRANGEMENTS OF WHEEL AXLES; RAIL VEHICLES FOR USE ON TRACKS OF DIFFERENT WIDTH; PREVENTING DERAILING OF RAIL VEHICLES; WHEEL GUARDS, OBSTRUCTION REMOVERS OR THE LIKE FOR RAIL VEHICLES (for vehicles in general B60; axles or wheels B60B; vehicle tyres B60C) - F15B: SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR ## Abstract A railcar damping device includes: a tank storing a liquid; a first opening/closing valve provided in a first passage connecting a rod side chamber and a piston side chamber, which are defined by a piston, to be capable of opening and closing the first passage; a second opening/closing valve provided in a second passage connecting the piston side chamber and the tank to be capable of opening and closing the second passage; a pump that is driven to rotate at a predetermined normal rotation speed in order to supply the liquid from the tank to the rod side chamber; and a temperature determination unit that determines a temperature of the liquid supplied to the actuator, wherein a rotation speed of the pump is reduced below a normal rotation speed when the temperature determination unit determines that the temperature of the liquid is lower than a predetermined temperature. ## Claims ### Claim 1 A railcar damping device that suppresses vibration of a vehicle body by controlling an actuator, wherein the actuator comprises: a cylinder coupled to one of a truck and a vehicle body of a railcar; a piston inserted into the cylinder to be free to slide; a rod inserted into the cylinder and coupled to the piston and the other of the truck and the vehicle body; and a rod side chamber and a piston side chamber defined within the cylinder by the piston, wherein the railcar damping device comprises: a tank that is configured to store a liquid that is supplied to and discharged from the cylinder; a first opening/closing valve provided in a first passage connecting the rod side chamber to the piston side chamber to be capable of opening and closing the first passage; a second opening/closing valve provided in a second passage connecting the piston side chamber to the tank to be capable of opening and closing the second passage; a pump that is configured to be driven to rotate at a predetermined normal rotation speed in order to supply the liquid from the tank to the rod side chamber; and a temperature determination unit that is configured to determine a temperature of the liquid supplied to the actuator, wherein a rotation speed of the pump is reduced below the normal rotation speed when the temperature determination unit determines that the temperature of the liquid is lower than a predetermined temperature. ### Claim 2 (depends on 1) The railcar damping device as defined in claim 1, wherein the temperature determination unit that is configured to determine whether or not the temperature of the liquid is lower than the predetermined temperature on the basis of date information. ### Claim 3 (depends on 1) The railcar damping device as defined in claim 1, wherein the temperature determination unit that is configured to determine whether or not the temperature of the liquid is lower than the predetermined temperature on the basis of air temperature information in a travel region of the railcar. ### Claim 4 (depends on 1) The railcar damping device as defined in claim 1, wherein the temperature determination unit that is configured to determine whether or not the temperature of the liquid is lower than the predetermined temperature on the basis of a travel position of the railcar. ### Claim 5 (depends on 1) The railcar damping device as defined in claim 1, wherein the temperature determination unit that is configured to determine whether or not the temperature of the liquid is lower than the predetermined temperature on the basis of time information. ### Claim 6 (depends on 1) The railcar damping device as defined in claim 1, wherein the temperature determination unit that is configured to determine whether or not the temperature of the liquid is lower than the predetermined temperature on the basis of an operation duration. ### Claim 7 (depends on 1) The railcar damping device as defined in claim 1, further comprising: an exhaust passage connecting the rod side chamber to the tank; and a variable relief valve that is provided midway in the exhaust passage and has a modifiable valve opening pressure. ### Claim 8 (depends on 7) The railcar damping device as defined in claim 7, wherein a thrust of the actuator is controlled by adjusting the valve opening pressure of the variable relief valve. ### Claim 9 (depends on 1) The railcar damping device as defined in claim 1, wherein, during an expansion operation of the actuator, a thrust is controlled by opening the first opening/closing valve and opening and closing the second opening/closing valve, and during a contraction operation of the actuator, the thrust is controlled by opening the second opening/closing valve and opening and closing the first opening/closing valve. ### Claim 10 (depends on 1) The railcar damping device as defined in claim 1, further comprising: a suction passage that is configured to allow the liquid to flow only from the tank toward the piston side chamber; and a rectifying passage that is configured to allow the liquid to flow only from the piston side chamber toward the rod side chamber.