US 11,873,894 B2
Working machine
Yuji Fukuda, Osaka (JP); Jun Tomita, Osaka (JP); Yuya Konishi, Osaka (JP); Fumitaka Fujisawa, Osaka (JP); Daiki Abe, Osaka (JP); Kohei Kurachi, Osaka (JP); Yudai Koga, Osaka (JP); and Yuya Tanabe, Osaka (JP)
Assigned to KUBOTA CORPORATION, Osaka (JP)
Filed by KUBOTA CORPORATION, Osaka (JP)
Filed on Aug. 9, 2021, as Appl. No. 17/397,168.
Claims priority of application No. 2020-137183 (JP), filed on Aug. 15, 2020; and application No. 2020-171638 (JP), filed on Oct. 12, 2020.
Prior Publication US 2022/0049727 A1, Feb. 17, 2022
Int. Cl. F16H 61/47 (2010.01); F16H 61/431 (2010.01); E02F 9/22 (2006.01); F15B 11/17 (2006.01); F16H 61/456 (2010.01); F16H 61/438 (2010.01); E02F 3/34 (2006.01)
CPC F16H 61/47 (2013.01) [E02F 9/2235 (2013.01); E02F 9/2253 (2013.01); E02F 9/2282 (2013.01); E02F 9/2285 (2013.01); E02F 9/2289 (2013.01); E02F 9/2292 (2013.01); E02F 9/2296 (2013.01); F15B 11/17 (2013.01); F16H 61/431 (2013.01); B60Y 2400/85 (2013.01); E02F 3/3414 (2013.01); E02F 9/2228 (2013.01); F15B 2211/20576 (2013.01); F15B 2211/6355 (2013.01); F15B 2211/7135 (2013.01); F16H 61/438 (2013.01); F16H 61/456 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A working machine comprising:
a machine body;
a left traveling device provided on a left portion of the machine body;
a right traveling device provided on a right portion of the machine body;
a left traveling motor configured to output power to the left traveling device;
a right traveling motor configured to output power to the right traveling device;
a left traveling pump, including a first pressure-receiving portion and a second pressure-receiving portion, configured to
normally rotate the left traveling motor when operation fluid is applied to the first pressure-receiving portion, and
reversely rotate the left traveling motor when operation fluid is applied to the second pressure-receiving portion;
a right traveling pump, including a third pressure-receiving portion and a fourth pressure-receiving portion, configured to
normally rotate the right traveling motor when operation fluid is applied to the third pressure-receiving portion, and
reversely rotate the right traveling motor when operation fluid is applied to the fourth pressure-receiving portion;
a traveling operation device, including a traveling operation member and a plurality of operation valves actuated according to operation of the traveling operation member, configured to apply the operation fluid to at least any one of the first, second, third and fourth pressure-receiving portions according to operation of the traveling operation member;
a first traveling fluid passage fluidly connecting an output port of a first high-pressure selector valve to the first pressure-receiving portion and configured so that the operation fluid to be applied to the first pressure-receiving portion flows through the first traveling fluid passage when the traveling operation member is operated;
a second traveling fluid passage fluidly connecting an output port of a second high-pressure selector valve to the second pressure-receiving portion and configured so that the operation fluid to be applied to the second pressure-receiving portion flows through the second traveling fluid passage when the traveling operation member is operated;
a third traveling fluid passage fluidly connecting an output port of a third high-pressure selector valve to the third pressure-receiving portion and configured so that the operation fluid to be applied to the third pressure-receiving portion flows through the third traveling fluid passage when the traveling operation member is operated;
a fourth traveling fluid passage fluidly connecting an output port of a fourth high-pressure selector valve to the fourth pressure-receiving portion and configured so that the operation fluid to be applied to the fourth pressure-receiving portion flows through the fourth traveling fluid passage when the traveling operation member is operated;
a fifth traveling fluid passage on which the first, second, third and fourth high-pressure selector valves are disposed, the fifth traveling fluid passage connecting the plurality of operation valves, the first, second, third and fourth traveling fluid passages to each other;
first, second, third and fourth drain fluid passages connected to the first, second, third and fourth traveling fluid passages, respectively, and configured so that the operation fluid drains;
a restrictor provided on each of the first, second, third and fourth drain fluid passages; and
a connection fluid passage fluidly connecting at least two of the first, second, third and fourth traveling fluid passages directly to each other without utilizing the first, second, third and fourth drain fluid passages.