Patent ID: 8277364
Filing Date: 2012-10-02
Classification: F16H,Y10T

Abstract:
1. A clutch control device for hydraulically driven vehicle, comprising: a hydraulic pump that is driven by an engine; a first variable displacement hydraulic motor that is connected to the hydraulic pump in a closed-circuit and is driven by pressure oil from the hydraulic pump; a second hydraulic motor, which is one of a variable displacement type and a fixed displacement type, that is connected in parallel to the first hydraulic motor and is driven by pressure oil from the hydraulic pump; a travel drive shaft that is driven by outputs of the first hydraulic motor and the second hydraulic motor; a displacement control device that controls displacement of the first hydraulic motor between zero and a maximum displacement in accordance with load; a clutch device that engages or disengages a drive-train between the first hydraulic motor and the travel drive shaft; an engine speed detection unit that detects rotational speed of the engine; a vehicle speed detection unit that detects vehicle speed; and a clutch control unit that controls the clutch device in response to detected engine speed and vehicle speed, wherein: the clutch control unit controls the clutch device when vehicle speed increases so as to disengage the drive-train at a first vehicle speed in the case where a first engine speed has been detected, and so as to disengage the drive-train at a second vehicle speed, which is less than the first vehicle speed, in the case where a second engine speed, which is less than the first engine speed, has been detected.