Patent ID: 9726276
Date: 2017-08-08
CPC Classifications: B28C,F15B,F16H

Claim:
1. A mixer drum driving apparatus, comprising: a mixer drum carried on a frame of a concrete mixer truck to be free to rotate; a fluid pressure motor that drives the mixer drum to rotate; a fluid pressure pump that is driven by power from an engine of the concrete mixer truck in order to supply a working fluid to the fluid pressure motor; at least one auxiliary fluid pressure pump that is provided independently of the fluid pressure pump and is capable of supplying the working fluid to the fluid pressure motor so as to cause the mixer drum to perform agitation rotation; a plurality of motors configured to drive the at least one auxiliary fluid pressure pump to rotate; a control unit that controls rotation of the mixer drum, wherein, when the engine is stopped during the agitation rotation of the mixer drum, the control unit drives the at least one auxiliary fluid pressure pump to rotate by operating the plurality of motors selectively so that an agitation rotation speed of the mixer drum comes to be a predetermined speed, wherein, a load of the mixer drum is detected by detecting a pressure of the working fluid discharged from the at least one auxiliary fluid pressure pump, and wherein, the control unit controls a number of the motors selectively driving the at least one auxiliary fluid pressure pump to rotate in accordance with the load of the mixer drum; and a pressure sensor for detecting the pressure of the working fluid discharged from the at least one auxiliary fluid pressure pump to detect the load of the mixer drum.