Heat pump

Abstract

A heat pump ( 100 ) with an evaporator ( 50 ) for evaporating a fluid in order to obtain evaporated fluid is described; with a condenser ( 60 ) for condensing a compressed fluid; with a compressor having a first compressor stage ( 10 ) and a second compressor stage ( 20 ), the compressor being arranged in the flow direction of the evaporated fluid during operation of the heat pump ( 100 ) between the evaporator ( 50 ) and the condenser ( 60 ) and being designed to compress the evaporated fluid in order to obtain compressed fluid; and with a bridging duct ( 62 ) between the first compressor stage ( 10 ) and the condenser ( 60 ) in order to bridge the second compressor stage ( 20 ), a cross-section reducing element ( 70 ) being arranged in the bridging duct ( 62 ) in order to adjust a cross section of the bridging duct ( 62 ) so as to control a flow of compressed fluid from the first compressor stage ( 10 ) to the condenser ( 60 ). Furthermore, methods for operating and producing the heat pump are described.

1 . A heat pump having the following features:
 an evaporator for evaporating a fluid, in order to obtain evaporated fluid;   a condenser for condensing a compressed fluid;   a compressor having a first compressor stage and a second compressor stage, wherein the compressor is arranged in the flow direction of the evaporated fluid, during operation of the heat pump, between the evaporator and the condenser, and is configured to compress the evaporated fluid, in order to obtain the compressed fluid; and   a bridging channel between the first compressor stage and the condenser, in order to bridge the second compressor stage, wherein   a cross-section reducing element is arranged in the bridging channel, in order to set a cross-section of the bridging channel for controlling a through-flow of compressed fluid out of the first compressor stage to the condenser.   
     
     
         2 . The heat pump according to  claim 1 , wherein the first compressor stage and the second compressor stage are connected via a vapour duct. 
     
     
         3 . The heat pump according to  claim 1 , wherein the bridging channel comprises an opening into the first compressor stage, wherein the first compressor stage comprises an suction manifold for suctioning the evaporated fluid, and a conducting chamber for conducting the vaporous compressed fluid into the bridging channel. 
     
     
         4 . The heat pump according to  claim 1 , wherein the condenser comprises a pipe bundle or a helical pipe arrangement, through which liquid to be heated can flow, wherein the pipe bundle or the helical pipe arrangement is arranged laterally with respect to a further opening of the bridging channel, and wherein an suction manifold of a compressor of the second compressor stage is arranged above the pipe bundle or the helical pipe arrangement. 
     
     
         5 . The heat pump according to  claim 4 , wherein the further opening of the bridging channel is arranged such that vaporous fluid which enters the condenser through the further opening strikes the pipe bundle or the helical pipe arrangement laterally. 
     
     
         6 . The heat pump according to  claim 1 , wherein the cross-section reducing element is configured to assume a closed position or an open position, depending on the operation of the second compressor stage, wherein the cross-section reducing element is configured
 to assume the closed position when the second compressor stage is activated, or   to assume the open position when the second compressor stage is deactivated.   
     
     
         7 . The heat pump according to  claim 6 , wherein the cross-section reducing element is preloaded by means of a spring element in the closed position. 
     
     
         8 . The heat pump according to  claim 1 , wherein the cross-section reducing element is a flap or an orifice or a leaf door or a check valve. 
     
     
         9 . The heat pump according to  claim 6 , wherein the heat pump comprises a controller for controlling the cross-section reducing element into the open position or the closed position. 
     
     
         10 . The heat pump according to  claim 6 , wherein the first compressor stage is configured to build up a maximum achievable pressure, and the cross-section reducing element is configured to assume the open position when a pressure ratio between the condenser pressure and the evaporator pressure is smaller than the maximum achievable pressure of the first compressor stage, in order to conduct compressed fluid out of the first compressor stage, via the bridging channel, to the condenser. 
     
     
         11 . The heat pump according to  claim 6 , wherein the cross-section reducing element is configured to assume the closed position when the pressure ratio between the condenser pressure and the evaporator pressure is greater than the maximum achievable pressure of the first compressor stage, in order to conduct compressed fluid out of the first compressor stage, via the vapour duct, to the second compressor stage. 
     
     
         12 . The heat pump according to  claim 1 , wherein the first compressor stage is operable with N further compressor stages, wherein N is a natural number greater than or equal to two. 
     
     
         13 . The heat pump according to  claim 12 , wherein the first compressor stage and the N further compressor stages are arranged in a series connection, wherein in the case of N compressor stages two neighbouring compressor stages are in each case connected via a vapour duct. 
     
     
         14 . A method for operating a heat pump comprising an evaporator for evaporating a fluid, in order to obtain evaporated fluid; a condenser for condensing a compressed fluid; a compressor having a first compressor stage and a second compressor stage, wherein the compressor is arranged in the flow direction of the evaporated fluid, during operation of the heat pump, between the evaporator and the condenser, and is configured to compress the evaporated fluid, in order to obtain the compressed fluid; and a bridging channel between the first compressor stage and the condenser, wherein the method comprises:
 bridging the second compressor stage by setting a cross-section of a cross-section reducing element in the bridging channel, in order to control a through-flow of compressed fluid out of the first compressor stage to the condenser.   
     
     
         15 . A method for producing a heat pump comprising an evaporator for evaporating a fluid, in order to obtain evaporated fluid; a condenser for condensing a compressed fluid; a compressor having a first compressor stage and a second compressor stage, wherein the compressor is arranged in the flow direction of the evaporated fluid, during operation of the heat pump, between the evaporator and the condenser, and is configured to compress the evaporated fluid, in order to obtain the compressed fluid; wherein the method comprises:
 arranging a bridging channel between the first compressor stage and the condenser, in order to bridge the second compressor stage;   arranging a cross-section reducing element in the bridging channel, in order to set a cross-section of the bridging channel, in order to control a through-flow of compressed fluid out of the first compressor stage to the condenser.