Working machine and method for operating working machine

• US 9,624,646 B2
• Filed: 09/18/2014
• Issued: 04/18/2017
• Est. Priority Date: 11/13/2013
• Status: Active Grant

• Current Assignee: Kubota Corporation
• Original Assignee: Kubota Corporation
• Inventors: Kuroda, Masahiro, Kinugawa, Ryosuke, Saijo, Naohiro
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): GOLDMAN, RICHARD A
• Application Number:
  US14/489,947
• Publication Number:
  US 20150132094A1
• Time in Patent Office: 943 Days
• Field of Search: 60421, 60486, 60422, 701 50, 701 2, 701 99
• CPC Class Codes: E02F 3/3414 the arms being pivoted at the rear of the vehicle chassis, e.g. skid steer loader
• CPC Class Codes: E02F 9/2004 Control mechanisms, e.g. control levers control levers per se G05G
• CPC Class Codes: E02F 9/2228 including an electronic controller
• CPC Class Codes: E02F 9/2282 Systems using center bypass type changeover valves
• CPC Class Codes: E02F 9/2285 Pilot-operated systems

Abstract

A working machine includes: a first switch operable to set an operation amount; a second switch operable by being pressed; a control unit capable of detecting an operation of the first switch and an operation of the second switch, the control unit outputting a control signal based on the operation amount of the first switch and continuously outputting the control signal when the operation of the first switch is detected after detecting a release of the operation of the second switch under a state where the operation of the second switch is detected; an actuator configured to be activated by a hydraulic operation fluid; a solenoid valve capable of controlling, based on the control signal, a pilot pressure; and a control valve configured to supply, based on the pilot pressure, the hydraulic operation fluid to the actuator.

Claims

1. A working machine comprising:

a machine frame;

a cabin disposed on the machine frame;

a boom disposed on a side of the cabin;

an auxiliary attachment configured to be attached to and detached from a tip end portion of the boom;

an actuator configured to be activated by an operation fluid and to activate the auxiliary attachment;

a solenoid valve having a solenoid and being configured to control, based on a control signal outputted to the solenoid, a pilot pressure being a pressure of a pilot fluid different from the operation fluid;

an auxiliary control valve configured to supply, based on the pilot pressure controlled by the solenoid valve, the operation fluid to the actuator;

an operation member having a head portion;

a first switch being disposed on the head portion of the operation member and being operable to set an operation amount;

a second switch being disposed on the head portion of the operation member and being operable by being pressed, the second switch being configured to automatically return to an initial position; and

a control unit configured to detect an operation of the first switch and an operation of the second switch, the control unit further being configured to;

output a control signal based on the operation amount of the first switch,

continuously output the control signal to the solenoid of the solenoid valve when the operation of the first switch is detected after detecting a release of the operation of the second switch under a state where the operation of the second switch is detected, and

release a continuous mode by further performing the operation of the second switch under a state where the control unit is in the continuous mode or to release the continuous mode by further performing the operation of the first switch under a state where the actuator is activated in the continuous mode.

2. The working machine according to claim 1, wherein

the control unit continuously outputs the control signal to the solenoid valve when the operation amount of the first switch reaches a maximum extent after detecting an operation of the first switch under a state where the release of the operation of the second switch is detected.

3. The working machine according to claim 2, wherein

the control unit continuously outputs a control signal, the control signal being to maximize the pilot pressure to the solenoid valve when the operation amount of the first switch reaches the maximum extent.

4. The working machine according to claim 1, wherein

the control unit continuously outputs a control signal, the control signal being to maximize the pilot pressure, to the solenoid valve when an operation of the first switch is detected after detecting the release of the operation of the second switch.

5. The working machine according to claim 1, further comprising:

a first pump configured to discharge the operation fluid;

a second pump configured to discharge the pilot fluid;

a discharge path configured to connect the auxiliary control valve and the first pump to each other to enable the auxiliary control valve to receive the operation fluid;

a pilot fluid path configured to connect the solenoid valve and the second pump to each other to enable the solenoid valve to receive the pilot fluid;

a connection unit disposed on the boom and configured to be connected to a hydraulic hose connected to the actuator; and

a hydraulic operation fluid supply path configured to connect the connection unit and the auxiliary control valve.

6. The working machine according to claim 1, wherein the control unit has:

the continuous mode to continuously output the control signal; and

a discontinuous mode to output the control signal when the first switch is operated.

7. The working machine according to claim 1, wherein

the second switch is disposed opposed to the first switch on the head portion of the operation member.

8. A working machine comprising:

a machine frame;

a cabin disposed on the machine frame;

at least one boom disposed on a side of the cabin;

an auxiliary attachment configured to be attached to and detached from an attachment portion of the boom;

an actuator configured to be activated by an operation fluid and to activate the auxiliary attachment;

a solenoid valve having a solenoid and being configured to control, based on a control signal outputted to the solenoid, a pilot pressure;

an auxiliary control valve configured to supply, based on the pilot pressure controlled by the solenoid valve, the operation fluid to the actuator;

an operation handle;

a first switch disposed on the operation handle and being a rocker switch or a three-position switch;

a push-button switch being disposed on the operation handle and being configured to automatically return to an initial position when not pressed; and

a control unit connected to the first switch and to the push-button switch and being configured to change operation between a discontinuous mode and a continuous mode,

wherein, when the continuous mode is activated, the control unit continuously outputs the control signal to the solenoid of the solenoid valve,

wherein the continuous mode is activated when;

the push-button switch is pressed;

then, the push-button switch returns an initial position; and

then, activation of the first switch is detected, and

wherein the continuous mode is released when;

the operation of the push-button switch is further performed under a state where the control unit is in the continuous mode;

or

the operation of the first switch is further performed under a state where the actuator is activated in the continuous mode.

9. The working machine according to claim 8, wherein the discontinuous mode is a default mode.