Uniaxial eccentric screw pump

Abstract

A uniaxial eccentric screw pump includes: a casing 1; a stator 2 having one end portion thereof connected to the casing 1 and having an inner peripheral surface formed into a female threaded shape; a rotor 3 configured to be insertable into the stator 2 and formed of a shaft body having a male threaded shape; and an end stud 4 connected to the other end portion of the stator 2. The stator 2 is formed of: a stator body 10; and an outer sleeve 9 detachably disposed on an outer peripheral portion of the stator body 10. A closure structure which at least prevents intrusion of a foreign material from the outside is provided at a junction between the stator body 10 and the casing 1 and at a junction between the stator body 10 and the end stud 4.

1 . A uniaxial eccentric screw pump comprising:
 a casing;   a stator having one end portion thereof connected to the casing and having an inner peripheral surface formed into a female threaded shape;   a rotor configured to be insertable into the stator and formed of a shaft body having a male threaded shape; and   an end stud connected to a second end portion of the stator, wherein   the stator is formed of: a stator body; and an outer sleeve detachably disposed on an outer peripheral portion of the stator body, and   a closure structure which at least prevents intrusion of a foreign material from the outside is provided at a junctions between the stator body and the casing and at a junctions between the stator body and the end stud.   
     
     
         2 . The uniaxial eccentric screw pump according to  claim 1 , wherein the closure structure is a seal structure which is configured to prevent leakage of a fluid material to the outside from the one end portion and the second end portion of the stator. 
     
     
         3 . The uniaxial eccentric screw pump according to  claim 1 , wherein the stator body is made of rubber or a resin material, and the outer sleeve is made of a metal material. 
     
     
         4 . The uniaxial eccentric screw pump according to  claim 1 , wherein the closure structure includes:
 flange portions formed on connection portions of the end stud and the stator;   a first clamp configured to hold the flange portions in a state where the flange portions are brought into contact with each other;   second flange portions formed on connection portions of the casing and the stator; and   a second clamp configured to hold the second flange portions in a state where the second flange portions are brought into contact with each other.   
     
     
         5 . The uniaxial eccentric screw pump according to  claim 1 , further comprising:
 a stay bolt which connects the casing and the end stud to each other; and   a spacer, which is mounted on the stay bolt from the outside, which is brought into contact with the casing and the end stud, and maintains the casing and the end stud with a fixed distance therebetween.   
     
     
         6 . The uniaxial eccentric screw pump according to  claim 1 , wherein the outer sleeve is formed of a plurality of covers formed by splitting the outer sleeve in a circumferential direction, and
 the uniaxial eccentric screw pump includes an adjusting unit configured to adjust a gap between the covers.   
     
     
         7 . The uniaxial eccentric screw pump according to  claim 6 , further comprising:
 a detection unit configured to detect a degree of expansion of the stator body toward the outer diameter side; and   a control unit configured to automatically adjust the gap between the covers by performing a drive control of the adjusting unit based on a detection value from the detection unit.   
     
     
         8 . The uniaxial eccentric screw pump according to  claim 2 , wherein the stator body is made of rubber or a resin material, and the outer sleeve is made of a metal material. 
     
     
         9 . The uniaxial eccentric screw pump according to  claim 2 , wherein the closure structure includes:
 flange portions formed on connection portions of the end stud and the stator;   a first clamp configured to hold the flange portions in a state where the flange portions are brought into contact with each other;   second flange portions formed on connection portions of the casing and the stator; and   a second clamp configured to hold the second flange portions in a state where the second flange portions are brought into contact with each other.   
     
     
         10 . The uniaxial eccentric screw pump according to  claim 3 , wherein the closure structure includes:
 flange portions formed on connection portions of the end stud and the stator;   a first clamp configured to hold the flange portions in a state where the flange portions are brought into contact with each other;   second flange portions formed on connection portions of the casing and the stator; and   a second clamp configured to hold the second flange portions in a state where the second flange portions are brought into contact with each other.   
     
     
         11 . The uniaxial eccentric screw pump according to  claim 2 , further comprising:
 a stay bolt which connects the casing and the end stud to each other; and   a spacer, which is mounted on the stay bolt from the outside, which is brought into contact with the casing and the end stud, and maintains the casing and the end stud with a fixed distance therebetween.   
     
     
         12 . The uniaxial eccentric screw pump according to  claim 3 , further comprising:
 a stay bolt which connects the casing and the end stud to each other; and   a spacer, which is mounted on the stay bolt from the outside, which is brought into contact with the casing and the end stud, and maintains the casing and the end stud with a fixed distance therebetween.   
     
     
         13 . The uniaxial eccentric screw pump according to  claim 4 , further comprising:
 a stay bolt which connects the casing and the end stud to each other; and   a spacer, which is mounted on the stay bolt from the outside, which is brought into contact with the casing and the end stud, and maintains the casing and the end stud with a fixed distance therebetween.   
     
     
         14 . The uniaxial eccentric screw pump according to  claim 2 , wherein the outer sleeve is formed of a plurality of covers formed by splitting the outer sleeve in a circumferential direction, and
 the uniaxial eccentric screw pump includes an adjusting unit configured to adjust a gap between the covers.   
     
     
         15 . The uniaxial eccentric screw pump according to  claim 3 , wherein the outer sleeve is formed of a plurality of covers formed by splitting the outer sleeve in a circumferential direction, and
 the uniaxial eccentric screw pump includes an adjusting unit configured to adjust a gap between the covers.   
     
     
         16 . The uniaxial eccentric screw pump according to  claim 4 , wherein the outer sleeve is formed of a plurality of covers formed by splitting the outer sleeve in a circumferential direction, and
 the uniaxial eccentric screw pump includes an adjusting unit configured to adjust a gap between the covers.   
     
     
         17 . The uniaxial eccentric screw pump according to  claim 5 , wherein the outer sleeve is formed of a plurality of covers formed by splitting the outer sleeve in a circumferential direction, and
 the uniaxial eccentric screw pump includes an adjusting unit configured to adjust a gap between the covers.