Hydraulic damper

Abstract

A hydraulic damper includes: a cylinder containing liquid; a piston part configured to be connected to a rod moving in an axial direction and configured to move inside the cylinder; a channel forming part including a first channel in which the liquid flows along with movement of the piston part in one direction, and a second channel in which the liquid flows parallel to the first channel along with the movement of the piston part in the one direction; a valve part configured to control flow of the liquid in the first channel and the second channel; and a single advancing/retracting part configured to advance and retract the valve part to and from the first channel and the second channel.

1 . A hydraulic damper comprising:
 a cylinder containing liquid;   a piston part configured to be connected to a rod moving in an axial direction and configured to move inside the cylinder;   a channel forming part including a first channel in which the liquid flows along with movement of the piston part in one direction, and a second channel in which the liquid flows parallel to the first channel along with the movement of the piston part in the one direction;   a valve part configured to control flow of the liquid in the first channel and the second channel; and   a single advancing/retracting part configured to advance and retract the valve part to and from the first channel and the second channel.   
     
     
         2 . The hydraulic damper according to  claim 1 , wherein
 the valve part includes a first channel facing portion and a second channel facing portion, the first channel facing portion being of a planar shape and facing the first channel, the second channel facing portion being of a planar shape and facing the second channel.   
     
     
         3 . The hydraulic damper according to  claim 2 , wherein
 the valve part includes a planar member integrally formed with the first channel facing portion and the second channel facing portion.   
     
     
         4 . The hydraulic damper according to  claim 3 , wherein
 the planar member at least includes an opening between the first channel facing portion and the second channel facing portion.   
     
     
         5 . The hydraulic damper according to  claim 2 , wherein
 the first channel protrudes more than the second channel toward the valve part, and   the advancing/retracting part is configured to bring the valve part close to the first channel and the second channel by contacting the second channel facing portion of the valve part.   
     
     
         6 . The hydraulic damper according to  claim 1 , wherein
 the channel forming part is integrally formed with the first channel and the second channel.   
     
     
         7 . The hydraulic damper according to  claim 1 , further comprising:
 a second channel forming part configured to form a third channel in which the liquid flows parallel to the first channel and the second channel along with the movement of the piston part in the one direction;   another valve part configured to control flow of the liquid in the third channel; and   a pressing part including an accommodation chamber for accommodating the liquid and configured to press the another valve part against the third channel by pressure of the liquid in the accommodation chamber, wherein   the first channel is a channel configured to adjust the pressure of the liquid in the accommodation chamber.   
     
     
         8 . The hydraulic damper according to  claim 7 , wherein
 the advancing/retracting part is configured to advance and retract the valve part to and from the first channel and the second channel according to an energization state of the advancing/retracting part, and   the advancing/retracting part includes a restricting part, the restricting part being configured to restrict the liquid from flowing out from the accommodation chamber through the first channel when the advancing/retracting part is not energized.   
     
     
         9 . The hydraulic damper according to  claim 1 , wherein
 the valve part includes:
 a held portion configured to be held by the channel forming part; 
 a first supporting portion configured to be connected to the held portion and to support a first controlling portion, the first controlling portion being configured to control flow of the liquid in the first channel; and 
 a second supporting portion configured to be connected to the first controlling portion and to support a second controlling portion, the second controlling portion being configured to control flow of the liquid in the second channel. 
   
     
     
         10 . The hydraulic damper according to  claim 9 , wherein
 at least one of the first supporting portion and the second supporting portion includes a portion extending along a circumferential direction.   
     
     
         11 . The hydraulic damper according to  claim 9 , wherein
 a width of the first supporting portion is larger at a portion thereof near the held portion than at a portion thereof farther from the held portion, and   the width of the first supporting portion is larger at a portion thereof near the first controlling portion than at a portion thereof farther from the first controlling portion.   
     
     
         12 . The hydraulic damper according to  claim 9 , wherein
 a width of the second supporting portion is larger at a portion thereof near the first controlling portion than at a portion thereof farther from the first controlling portion, and   the width of the second supporting portion is larger at a portion thereof near the second controlling portion than at a portion thereof farther from the second controlling portion.   
     
     
         13 . The hydraulic damper according to  claim 9 , wherein
 the first supporting portion is provided at an outside in a radial direction of an opening formed in the valve part and having a largest opening area.   
     
     
         14 . The hydraulic damper according to  claim 9 , wherein
 the first controlling portion is provided at a center of the valve part, and   the second controlling portion is supported by an end of the second supporting portion extending from the first controlling portion toward an outside in a radial direction.   
     
     
         15 . A hydraulic damper comprising:
 a cylinder containing liquid;   a piston part configured to be connected to a rod moving in an axial direction and configured to move inside the cylinder;   a first valve part configured to throttle one channel in which the liquid flows along with movement of the piston part;   a pressing part including an accommodation chamber for accommodating the liquid and configured to press the first valve part against the one channel by pressure of the liquid in the accommodation chamber; and   a second valve part configured to throttle another channel provided parallel to the one channel and in which the liquid flows along with movement of the piston part, and to throttle a pressure channel provided separately from the another channel and configured to change the pressure of the liquid in the accommodation chamber.