Permanent magnet linear piston pump

Abstract

A permanent magnet linear piston pump comprises a piston body, a cylinder body, a permanent magnet assembly and an electromagnetic coil. The piston body is arranged in a piston cavity by a liquid sealing movable fit mode. An inner magnetic body and an outer magnetic body are disposed on at least one side surface of the cylinder body. An electromagnetic coil is axially and distributively wound around a coil supporting member which is disposed at an outside surface of the cylinder body. The electromagnetic coil is disposed between the inner magnetic body and the outer magnetic body. By the above structure, the pump needs not subject the electromagnetic coil to a sealing treatment, thereby attaining a simple structure, more convenient manufacture, lower costs, a reliable operation and convenient maintenance.

What is claimed is: 
     
         1 . A permanent magnet linear piston pump comprising a piston body ( 1 ), a cylinder body ( 2 ), a permanent magnet assembly ( 6 ) and an electromagnetic coil ( 3 );
 characterized in that said cylinder body ( 2 ) is in a shape of a polygonal prism, in which a piston cavity ( 201 ) is formed by an axial columnar accommodating cavity, said piston body ( 1 ) being disposed in said piston cavity ( 201 ) by a liquid sealing movable fit mode, a one-way inlet valve ( 4 ) and a one-way outlet valve ( 5 ) being disposed on an end face of said piston cavity ( 201 ) opposite to an end face of a piston, a set of permanent magnet assembly ( 6 ) being disposed on at least one side surface of said cylinder body ( 2 ), said permanent magnet assembly ( 6 ) including an inner mounting plate ( 601 ) and an outer mounting plate ( 602 ) disposed parallel to said side surface of said cylinder body ( 2 ), said inner mounting plate ( 601 ) and said outer mounting plate ( 602 ) being made of a permeability magnetic material, an inner magnetic body ( 603 ) and an outer magnetic body ( 604 ) being respectively disposed on opposite surfaces of said inner mounting plate ( 601 ) and said outer mounting plate ( 602 ), said inner magnetic body ( 603 ) and said outer magnetic body ( 604 ) being disposed oppositely and providing contrary magnetic poles at opposite faces thereof, a coil supporting member being disposed at an outside surface of said cylinder body ( 2 ), said electromagnetic coil ( 3 ) being axially and distributively wound around said coil supporting member into a barrel shape, a barrel wall formed by said electromagnetic coil ( 3 ) being disposed between said inner magnetic body ( 603 ) and said outer magnetic body ( 604 ), an axial sliding slot ( 203 ) being formed on said side surface of said cylinder body ( 2 ) where said permanent magnet assembly ( 6 ) is disposed, a connecting post ( 101 ) being radially disposed on a side surface of said piston body ( 1 ) to fit in with said sliding slot ( 203 ) by a clearance fit mode, said connecting post ( 101 ) penetrating through said sliding slot ( 203 ) to be in connection with and in linkage with said inner mounting plate ( 601 ) and said outer mounting plate ( 602 ).   
     
     
         2 . The permanent magnet linear piston pump according to  claim 1 , wherein two parts of said columnar accommodating cavity in said cylinder body ( 2 ) are disposed symmetrically, said piston body ( 1 ) being disposed at a middle portion of said columnar accommodating cavity, two ends of said piston body ( 1 ) being in cooperation with said two parts of said columnar accommodating cavity by said liquid sealing movable fit mode respectively, whereby said two parts of said columnar accommodating cavity are respectively defined as a first piston cavity ( 2011 ) and a second piston cavity ( 2012 ) and said two ends of said piston body are respectively defined as a first piston body ( 1   a ) and a second piston body ( 1   b ), a first one-way inlet valve ( 4   a ) and a first one-way outlet valve ( 5   a ) being disposed on an end face of said first piston cavity ( 2011 ) opposite to an end face of said first piston body ( 1   a ), a second one-way inlet valve ( 4   b ) and a second one-way outlet valve ( 5   b ) being disposed on an end face of said second piston cavity ( 2012 ) opposite to an end face of said second piston body ( 1   b ), a first inner magnetic body ( 603   a ) and a second inner magnetic body ( 603   b ) being respectively and symmetrically disposed at two ends of said inner mounting plate ( 601 ), a first outer magnetic body ( 604   a ) and a second outer magnetic body ( 604   b ) being respectively and symmetrically disposed at two ends of said outer mounting plate ( 602 ), a first electromagnetic coil ( 3   a ) and a second electromagnetic coil ( 3   b ) being respectively and correspondingly disposed on ribs ( 202 ) at two sides of said cylinder body ( 2 ). 
     
     
         3 . The permanent magnet linear piston pump according to  claim 1 , wherein one set of permanent magnet assembly ( 6 ) is arranged at each side surface of said cylinder body ( 2 ). 
     
     
         4 . The permanent magnet linear piston pump according to  claim 1 , wherein ribs ( 202 ) are disposed on edges of said cylinder body ( 2 ), said ribs ( 202 ) constructing said coil supporting member, said inner mounting plate ( 601 ) and said inner magnetic body ( 603 ) being disposed in a recess between said ribs ( 202 ) at two sides of a same side surface of said cylinder body ( 2 ). 
     
     
         5 . The permanent magnet linear piston pump according to  claim 1 , wherein said cylinder body ( 2 ) includes a barrel unit and lids at two ends thereof, sealing rings being respectively disposed between said lids at said two ends and two end faces of said barrel unit, said barrel unit and said lids at said two ends being connected with each other by a plurality of axial shanks and nuts around an outer periphery of said barrel unit, said shanks constructing said coil supporting member. 
     
     
         6 . The permanent magnet linear piston pump according to  claim 1 , wherein said cylinder body ( 2 ) is a prism having four to six sides. 
     
     
         7 . The permanent magnet linear piston pump according to  claim 1 , wherein said cylinder body ( 2 ) is a quadrangular prism, a cross-section of which is in a rectangular shape. 
     
     
         8 . The permanent magnet linear piston pump according to  claim 1 , wherein said inner mounting plate ( 601 ) and said outer mounting plate ( 602 ) are made of a permeability magnetic material, a magnetizing coil ( 7 ) being sleeved on said inner mounting plate ( 601 ) or/and said outer mounting plate ( 602 ), a magnetic field line created by said magnetizing coil ( 7 ) being formed in a closed annular shape along said inner mounting plate ( 601 ), said inner magnetic body ( 603 ), said outer magnetic body ( 604 ) and said outer mounting plate ( 602 ).