Rankine cycle system

Abstract

In a configuration in which a first shaft portion configured to drive a pump mechanism and a second shaft portion configured to drive an expansion mechanism are coupled to each other, a Rankine cycle system which is capable of continuing the circulation of working fluid by an expansion machine even when the pump mechanism is locked is provided. This Rankine cycle system of the invention employs a pump and an expansion machine coupled in a tandem manner. A first shaft of the pump and a second shaft of the expansion machine are concentric and the first shaft is capable of transmitting power to the second shaft. A pump torque limiter is provided between the first shaft and a main gear. A one-way clutch is provided between a sensing shaft and the second shaft.

1 . A Rankine cycle system comprising: a pump; a boiler; an expansion machine; a condenser; and pipes;
 the pipes are connecting the pump to the condenser via the boiler and the expansion machine for circulating the working fluid, wherein   the pump includes a first shaft portion coupled to a drive source, and a pump mechanism capable of being rotated by the first shaft portion,   the expansion machine includes a second shaft portion coupled to the first shaft portion, and an expansion mechanism rotatable by the second shaft portion, and   a pump torque limiter is provided between the first shaft portion and the pump mechanism.   
     
     
         2 . The Rankine cycle system according to  claim 1  wherein
 the first shaft portion and the second shaft portion are concentric, 
 a one-way clutch is provided between the first shaft portion and the second shaft portion so as to block power transmission between the second shaft portion and the first shaft portion if the rotational speed of the second shaft portion is smaller than the rotational speed of the first shaft portion, and allow the power transmission between the second shaft portion and the first shaft portion if the rotational speed of the second shaft portion reaches to exceed the rotational speed of the first shaft portion, 
 the pump is provided with a sensing shaft configured to rotate when the pump mechanism is in operation, and 
 the one-way clutch allows the power transmission between the second shaft portion and the first shaft portion even when the rotational speed of the second shaft portion is smaller than the rotational speed of the first shaft portion when the rotation of the sensing shaft is stopped. 
 
     
     
         3 . The Rankine cycle system according to  claim 2 , wherein
 the sensing shaft is a cylindrical shape concentric with the first shaft portion,   the one way clutch includes:   an outer race configured to rotate integrally with the second shaft portion and formed with a cylindrical inner peripheral rolling surface;   an inner race configured to rotate integrally with the first shaft portion and formed with a polygonal outer peripheral rolling surface;   rollers configured to be stored between the inner peripheral rolling surface and the outer peripheral rolling surface;   stators provided as many as the rollers and fixed to the inner race;   forward urging springs provided between the stators and the rollers respectively, and having a forward urging force which causes the respective rollers to be positioned on the front side in the direction of rotation of the first shaft portion;   a holder configured to hold the respective rollers between the inner peripheral rolling surface and the outer peripheral rolling surface; and   a sensing spring provided between the sensing shaft and the holder.   
     
     
         4 . The Rankine cycle system according to  claim 3 , wherein
 the one-way clutch includes rearward urging springs provided between the respective stators and the respective rollers and having a rearward urging force which causes the respective rollers to be positioned on the rear side of the first shaft portion in the direction of rotation, and   the rearward urging force is weaker than the forward urging force.   
     
     
         5 . The Rankine cycle system according to  claim 1 , wherein
 the first shaft portion and the second shaft portion are concentric, and   an expansion machine torque limiter is provided between the second shaft portion and the first shaft portion.