Refrigerant compressor having linear drive

Abstract

A coolant compressor has a hermetically sealed compressor housing, in the interior of which lies a piston cylinder unit that compresses a coolant. The cylinder housing of the piston cylinder unit is closed at the front end thereof by a cylinder head. A linear drive is provided, comprising at least one oscillating body which is surrounded by an excitation winding and which is connected to the piston to move same along a longitudinal axis in an oscillating manner. The piston cylinder unit has at least one first permanent magnet that lies on the piston, and at least one second permanent magnet that lies on the cylinder housing. Both magnets face each other and are oriented in the same magnetic pole direction in order to generate a repelling effect between both magnets to limit the path of the piston in the region of the top or bottom dead center.

1 - 23 . (canceled) 
     
     
         24 . A refrigerant compressor having a hermetically sealed compressor housing, in whose interior a piston-cylinder unit ( 21 ), which compresses a refrigerant, is arranged, whose cylinder housing ( 1 ) is frontally closed by means of a cylinder head ( 4 ), in which a suction opening ( 17 ) and a pressure opening ( 18 ) are provided, via which refrigerant is suctioned in via a suction valve ( 15 ) through the suction opening and compressed via a pressure valve ( 16 ) to the pressure opening, the piston-cylinder unit ( 21 ) having at least one piston ( 3 ) guided in a piston bore ( 2 ) of the cylinder housing ( 1 ), a working space ( 14 ) for compressing a refrigerant being formed between the cylinder head ( 4 ) and a first front side ( 3   a ) of the piston ( 3 ), a linear drive ( 6 ) being provided, comprising at least one oscillating body ( 7 ) enclosed by an exciter winding ( 8 ), which is connected to the piston ( 3 ), in order to move it along a piston longitudinal axis ( 9 ) in oscillating manner, the piston-cylinder unit ( 21 ) being equipped with at least one permanent magnet arrangement, comprising respectively at least one first permanent magnet ( 11 ) arranged on the piston ( 3 ) or on a component connected to the piston ( 3 ), wherein the at least one permanent magnet arrangement comprises at least one second permanent magnet ( 12 ) arranged on the cylinder housing ( 1 ) or on a component connected to the cylinder housing ( 1 ), the first permanent magnet ( 11 ) and the second permanent magnet ( 12 ) pointing toward one another with the same magnetic pole direction in each case, to generate a repelling effect between the two permanent magnets ( 11 ,  12 ) to delimit the piston travel in the region of the top dead center and/or in the region of the bottom dead center upon approach of the first permanent magnet ( 11 ) to the second permanent magnet ( 12 ), the component connected to the cylinder housing ( 1 ), on or in which the at least one second permanent magnet ( 12 ) is arranged, is the cylinder head ( 4 ), a valve plate ( 5 ) is arranged in the cylinder head ( 4 ) and the at least one second permanent magnet ( 12 ) is arranged on the valve plate ( 5 ), preferably at least sectionally countersunk in the valve plate ( 5 ), in order to delimit the piston travel in the region of the top dead center, the permanent magnets ( 11 ,  12 ) are countersunk into the front side ( 3   a,    3   b ) of the piston ( 3 ) and/or the valve plate ( 5 ) so that at least one free space ( 13 ) is provided between permanent magnet and piston or valve plate, which communicates with the working space ( 14 ), and this free space ( 13 ) extends along the entire periphery of the permanent magnets ( 11 ,  12 ). 
     
     
         25 . The refrigerant compressor according to  claim 24 , wherein the component connected to the piston ( 3 ), on which the at least one first permanent magnet ( 11 ) is arranged, is the oscillating body ( 7 ) or a piston shaft ( 22 ) connecting the piston ( 3 ) to the oscillating body ( 7 ). 
     
     
         26 . The refrigerant compressor according to  claim 24 , wherein the at least one second permanent magnet ( 12 ) is arranged inside the piston bore ( 2 ) of the cylinder housing ( 1 ). 
     
     
         27 . The refrigerant compressor according to  claim 24 , wherein the at least one second permanent magnet ( 12 ) is arranged inside the working space ( 14 ) or to delimit the working space ( 14 ). 
     
     
         28 . The refrigerant compressor according to  claim 24 , wherein the at least one first permanent magnet ( 11 ) is arranged in the region of the first front side ( 3   a ) of the piston ( 3 ) facing toward the cylinder head ( 4 ). 
     
     
         29 . The refrigerant compressor according to  claim 28 , wherein the at least one first permanent magnet ( 11 ) is sectionally or entirely countersunk in the front side ( 3   a ) and/or in the piston shaft ( 22 ). 
     
     
         30 . The refrigerant compressor according to  claim 24 , wherein the free space ( 13 ) is implemented as a gap, whose clear opening width widens in the direction of the working space ( 14 ). 
     
     
         31 . The refrigerant compressor according to  claim 29 , wherein the free space ( 13 ) is filled using a non-ferromagnetic material. 
     
     
         32 . The refrigerant compressor according to  claim 24 , wherein the at least one first permanent magnet ( 11 ) is arranged opposite to the at least one second permanent magnet ( 12 ). 
     
     
         33 . The refrigerant compressor according to  claim 24 , wherein the permanent magnets ( 11 ,  12 ) are implemented as essentially ring-shaped, the ring shape preferably extending rotationally-symmetric to the piston longitudinal axis ( 9 ) and/or the free space preferably being implemented as a ring gap. 
     
     
         34 . The refrigerant compressor according to  claim 24 , wherein one front side ( 11   a ) of the at least one first permanent magnet ( 11 ) extends substantially parallel to one front side ( 12   a ) of the at least one second permanent magnet ( 12 ). 
     
     
         35 . The refrigerant compressor according to  claim 29 , wherein the at least one first permanent magnet ( 11 ) has an essentially equal field strength, preferably an essentially equal mass, as the at least one second permanent magnet ( 12 ). 
     
     
         36 . The refrigerant compressor according to  claim 29 , wherein multiple permanent magnets ( 11 ,  12 ) are arranged on a circle extending concentrically to the piston longitudinal axis ( 9 ), the angle spacing of adjacent permanent magnets ( 11 ,  12 ) being essentially equal. 
     
     
         37 . The refrigerant compressor according to  claim 24 , wherein the piston ( 3 ) is implemented as a double piston, comprising two piston sections ( 19 ,  20 ), arranged on opposing end regions of the double piston ( 3 ) and each forming one front side ( 3   a,    3   b ) of the double piston, a first working space ( 14 ) being formed between the first front side ( 3   a ) of the double piston ( 3 ) and a first cylinder head ( 4 ) comprising a first valve plate ( 5 ) and a second working space ( 14 ′) being formed between the second front side ( 3   b ) of the double piston ( 3 ) and a second cylinder head ( 4 ′) comprising a second valve plate ( 5 ′), and the oscillating body ( 7 ) being arranged between the two front side ( 3   a,    3   b ) of the double piston ( 3 ), preferably enclosed by the double piston ( 3 ), and one permanent magnet arrangement according to one of the preceding claims being provided for each cylinder head-piston section pair ( 4 / 19 ,  4 ′/ 20 ).