Abstract: A working machine includes a working device, a hydraulic system including an actuator, and a hydraulic pump to supply a hydraulic fluid to the actuator, an electric device, a power generator to generate electric power to be directly or indirectly supplied to the electric device, a first cooling system to cool the electric device with a first cooling medium, and a second cooling system to cool the power generator with a second cooling medium. The first cooling system includes a first heat exchanger to cool the hydraulic fluid through heat exchange with the first cooling medium, a second heat exchanger to cool the second cooling medium through heat exchange with the first cooling medium, and a third heat exchanger to cool the first cooling medium through heat exchange with outside air to a temperature lower than temperatures before the heat exchange of the hydraulic fluid and the second cooling medium.

Abstract: An electric working machine includes an electric device, electric circuitry electrically connected to the electric device, battery packs to be connected to the electric device via the electric circuitry, and a controller. The controller is configured or programmed to, in a driving mode, if a voltage difference between the battery packs is greater than a predetermined reference, connect one of the battery packs having a highest voltage to the electric device to drive the electric device.

Abstract: An electric working machine includes an electric device, battery packs, and a controller. The electric circuitry includes external relays corresponding to the respective battery packs. The controller is configured or programmed to perform an external relay test process to examine whether contacts of a corresponding external relay which corresponds to a second battery pack to be connected to second or later are locked, and, in the external relay test process, if a voltage between the positive and negative external terminals of the battery pack is equal to or more than a threshold, determine that the contacts of the external relay are locked, and, if the voltage between the positive and negative external terminals of the battery pack is less than the threshold, determine that the contacts of the external relay are normal.

Abstract: An electric working machine includes an electric device, electric circuitry, battery packs to be connected sequentially to the electric device via the electric circuitry to parallelly connected, the battery packs including internal relay(s) to open/close an internal circuit, and a controller. The electric circuitry includes external relays corresponding to respective battery packs. The controller is configured or programmed to perform a first latter process wherein, while a first battery pack to be connected first to the electric device is in electrical connection with the electric device, the controller brings the internal relay(s) of a second battery pack to be connected second or later to the electric device into a closed state, and a second latter process wherein the controller brings, into the closed state, the external relay corresponding to the second battery pack where the internal relay(s) is in the closed state.

Abstract: An electric working machine includes an electric device, electric circuitry, battery packs to be connected sequentially to the electric device such that they are connected in parallel, and a controller. The electric circuitry includes external relays corresponding to the respective battery packs. The controller is configured or programmed to specify each battery pack as being a battery pack requiring a test process to examine opening and closing actions of internal relay(s) of the battery pack or a battery pack not requiring the test process, and in connecting the battery packs to the electric device, perform the test process on battery pack(s) that have been specified as requiring the test process to examine the opening and closing actions, and not perform the test process on battery pack(s) that have been specified as not requiring the test process to examine the opening and closing actions.

Abstract: A hybrid system includes an engine, a generator to be driven by the engine, an electric actuator to be driven by electricity generated by the generator, a transmission to transmit power from the engine, a hydraulic pump to receive power from the engine through the transmission to deliver hydraulic fluid, and a hydraulic actuator to be driven by the hydraulic fluid. The transmission includes a first transmission path to transmit power from the engine to the hydraulic pump when a rotational speed of the engine is a first rotational speed, and a second transmission path to transmit power from the engine to the hydraulic pump at a speed change ratio at which a rotational speed is increased to a greater degree than at a speed change ratio of the first transmission path when the rotational speed of the engine is a second rotational speed lower than the first rotational speed.

Abstract: A work vehicle includes: a front wheel; a rear travel device; a travel body supported by the front wheel and the rear travel device; a driving section provided in the travel body and having an occupant floor section; a travel power transmission device configured to transmit power to the rear travel device; at least one electric motor coupled to the travel power transmission device; a first inverter connected to the at least one electric motor; and a second inverter connected to the at least one electric motor.

Abstract: A work vehicle including: a front wheel; a rear travel device; a travel body supported by the front wheel and the rear travel device; a driving section provided in the travel body and having an occupant floor section; a transmission configured to output power to the rear travel device; a transmission case housing the transmission; an electric motor coupled to the transmission; and an inverter connected to the electric motor, wherein: the inverter is provided between the front wheel and the rear travel device, under the floor section, and laterally of the transmission case.

Abstract: A work vehicle includes: a travel device; a battery; a motor configured to supply motive power to the travel device; an inverter configured to enable the motor to operate; a first storage section configured to store a first coolant; and a second storage section configured to store a second coolant. The first coolant in the first storage section is supplied to the motor by the first pump, and returns from the motor to the first storage section, and the second coolant in the second storage section is supplied to the inverter by the second pump, and returns from the inverter to the second storage section.

Abstract: A work vehicle includes: a travel device supporting a body; a battery; a motor configured to supply motive power to the travel device; an inverter configured to enable the motor to operate; a cabin supported by the body and housing a driving section that includes a driver seat; and an air conditioner configured to condition air inside the cabin. The inverter is inside the cabin.

Abstract: A work vehicle includes a hybrid transmission to vary power from an engine and output the power to a travel device, the hybrid transmission including an electric transmission including a motor generator and a gear transmission including a gear driver. The work vehicle includes an inverter to drive the motor generator. The work vehicle includes a pump to cool the inverter by supplying, to the inverter, a refrigerant to cool the motor generator.

Abstract: A hybrid transmission includes an electric transmission including a motor generator, and a gear transmission including a gear driver without a motor generator. A transmission case includes an electric transmission chamber in which the electric transmission is accommodated, and a gear transmission chamber in which the gear transmission is accommodated, the electric transmission chamber and the gear transmission chamber being adjacent to each other. The transmission case includes a partition wall separating the electric transmission chamber from the gear transmission chamber in a non-communication manner.

Abstract: A hybrid transmission includes an electric transmission and a gear transmission. The electric transmission includes a first motor generator and a second motor generator. The second motor generator is on a side of the first motor generator on which side the gear transmission is located. An output transmission to transmit the output from the second motor generator to the gear transmission is on the side of the second motor generator on which side the gear transmission is located.