Variable displacement dual vane pump

Abstract

The present invention is a variable displacement pump having an inner rotor rotatable about a first axis and having at least two slots. The pump also has at least two vanes, each located in a distinct one of the at least two slots. The pump also has an outer rotor rotatable about a second axis, operably associated with the inner rotor, the outer rotor having two or more recesses, each configured to receive one of the vanes. The pump also includes an expandable chamber formed by the outer rotor and the inner rotor, an eccentric ring surrounding the outer rotor, and a housing. The eccentric ring is located within the housing for adjusting the relative relationship between the first axis and the second axis in order to vary the displacement of the pump.

1 . A variable displacement pump, comprising:
 an inner rotor rotatable about a first axis having at least two slots, said at least two slots substantially extending diametrically through the width of said inner rotor;   at least two vanes, each located in a distinct one of said at least two slots;   an outer rotor rotatable about a second axis and operably associated with said inner rotor, said outer rotor having two or more recesses, each configured to received one of said at least two vanes;   an expandable chamber formed by said outer rotor and said inner rotor;   an eccentric ring surrounding said outer rotor; and   a housing having said eccentric ring located within said housing for adjusting the relative relationship between said first axis and said second axis in order to vary the displacement of said pump.   
   
   
       2 . The variable displacement pump of  claim 1 , further comprising:
 a flange formed as part of said eccentric ring;   a pivot hole formed as part of said eccentric ring; and   a pivot pin formed as part of said housing such that said pivot pin is disposed within said pivot hole of said eccentric ring such that a force is applied to said flange, thereby causing said eccentric ring to pivot about said pivot pin and the position of said first axis to become aligned with or offset from said second axis.   
   
   
       3 . The variable displacement pump of  claim 1 , further comprising:
 an inlet port formed as a portion of said housing; and   an outlet port formed as a portion of said housing such that when said inner rotor rotates, said at least two vanes will apply force to said at least two recesses of said outer rotor, causing said outer rotor to rotate, and when said first axis is offset from said second axis, said at least two vanes and said expandable chamber will transfer fluid from said inlet port to said outlet port.   
   
   
       4 . The variable displacement pump of  claim 1 , wherein each of said at least two vanes is further comprised of:
 a first side offset and parallel to a second side;   a third side connected to said first side and said second side;   a fourth side connected to said first side and said second side, with either of said third side or said fourth side forming at least one flat engagement; and   an extension of a reduced width in relation to the width of said third side and said fourth side, and said flat engagement is positioned at an angle relative to said first side and said second side, and is engaged with one of said at least two recesses of said outer rotor.   
   
   
       5 . The variable displacement pump of  claim 4 , wherein said flat engagement of each of said at least two vanes is slidably engaged with one of said at least two recesses of said outer rotor. 
   
   
       6 . The variable displacement pump of  claim 5 , wherein each of said at least two recesses is positioned at an angle which corresponds to said angle of said flat engagement, allowing said at least two vanes to transfer rotational force to said outer rotor. 
   
   
       7 . The variable displacement pump of  claim 6 , wherein said extension of one of said at least two vanes is adjacent to said extension of another of said at least two vanes, placing said at least two vanes in a stacked configuration. 
   
   
       8 . The variable displacement pump of  claim 1 , wherein said inner rotor is a straddle support inner rotor, comprising:
 a first hub portion;   a series of vane supports connected to said first hub portion;   a second hub portion connected to said series of vane supports on the opposite side of said vane supports in relation to said first hub portion; and   said at least two slots further comprising at least two elongated slots, each of said at least two elongated slots extending into a portion of either said first hub portion or said second hub portion.   
   
   
       9 . The variable displacement pump of  claim 8 , one of said at least two vanes further comprising a multi-piece vane which is received into one of said at least two slots. 
   
   
       10 . The variable displacement pump of  claim 1 , further comprising;
 a piston;   a flange formed as a portion of said eccentric ring;   a recess formed as a portion of said piston, said flange of said eccentric ring partially disposed in said recess;   a substantially flat portion formed as a portion of said piston;   a hollow portion formed as a portion of said piston; and   a return spring at least partially disposed in said hollow portion of said piston such that said return spring biases said first axis to be aligned with said second axis, and fluid pressure is applied to said substantially flat portion to overcome the force of said return spring such that said piston moves cause said flange to pivot said eccentric ring, thereby causing said first axis to become offset from said second axis.   
   
   
       11 . The variable displacement pump of  claim 1 , wherein said at least two vanes will remain substantially stationary relative to said at least two recesses, when said first axis is substantially aligned with said second axis. 
   
   
       12 . A sliding vane pump, comprising:
 a housing;   an inner rotor having a series of slots, said inner rotor operably positioned in said housing and rotatable about a first axis;   said housing having an inlet port and an outlet port;   a series of vanes, each of said series of vanes having a first side offset and parallel to a second side, a third side connected to said first side and said second side to form a flat engagement, and a fourth side connected to said first side and said second side to form a flat engagement, and an extension of a reduced width in relation to said the width of said third side and said fourth side, said series of vanes received by said series of slots;   an outer rotor having a series of recesses, each for receiving one of said series of vanes;   an expandable chamber located between said inner rotor and said outer rotor; and   an eccentric ring which circumscribes said outer rotor and is located within said housing, said eccentric ring having a flange, and a pivot hole, and when said inner rotor rotates, said series of vanes will rotate and drive said recesses of said outer rotor, causing said outer rotor to rotate, and when said first axis is offset from said second axis, said expandable chamber will transfer fluid from said inlet port to said outlet port, and when said first axis is aligned with said second axis, said expandable chamber will not transfer fluid from said inlet port to said outlet port.   
   
   
       13 . The sliding vane pump of  claim 12 , said housing further comprising a pivot pin formed as a portion of said housing, wherein said pivot pin is inserted through said pivot hole such that a force is applied to said flange, thereby causing said eccentric ring to pivot about said pivot pin, changing the position of said first axis in relation to said second axis. 
   
   
       14 . The sliding vane pump of  claim 12 , further comprising:
 an angle between said flat engagement of said third side in relation to said first side and said second side; and   an angle between said flat engagement of said fourth side in relation to said first side and said second side.   
   
   
       15 . The sliding vane pump of  claim 14 , wherein said series of recesses are positioned at said angle to slidably engage said flat engagement of said first end and said flat engagement of said second end. 
   
   
       16 . The sliding vane pump of  claim 12 , wherein said inner rotor is a straddle support inner rotor, further comprising:
 a series of vane supports, said series of slots formed by said series of vane supports;   a first hub portion connected to said series of vane supports; and   a second hub portion connected to said series of vane supports on the opposite side of said series of vane supports in relationship to said first hub portion.   
   
   
       17 . The sliding vane pump of  claim 16 , said series of slots further comprising:
 at least two elongated slots formed by said series of vane supports, wherein two of said series of vanes are disposed within said at least two elongated slots.   
   
   
       18 . The sliding vane pump of  claim 16 , said series of vanes further comprising at least two multi-piece vanes, wherein said at least two multi-piece vanes are disposed within two of said at least two slots. 
   
   
       19 . The sliding vane pump of  claim 12 , further comprising:
 a piston having a recess formed as a portion of said piston, said recess receives a portion of flange of said eccentric ring;   a substantially flat portion formed as a portion of said piston; and   a hollow portion formed as a portion of said piston, said hollow portion operable for receiving a portion of a return spring such that said return spring biases said first axis of said inner rotor to be aligned with said second axis of said outer rotor, and said piston applies a force to said flange to cause said eccentric ring to pivot about said pivot hole and said first axis to become offset from said second axis when fluid pressure is applied to said substantially flat portion.   
   
   
       20 . The sliding vane pump of  claim 12 , further comprising said flat engagement of said first end of said series of vanes and said flat engagement of said second end of said series of vanes will slide in said recesses when said series of vanes rotate said outer rotor, and said first axis is offset from said second axis. 
   
   
       21 . The sliding vane pump of  claim 12 , further comprising said flat engagement of said first end of said series of vanes and said flat engagement of said second end of said series of vanes will remain substantially stationary relative to said recesses when said series of vanes rotate said outer rotor, and said first axis is substantially aligned with said second axis. 
   
   
       22 . A sliding vane pump which is used for pumping fluid, comprising:
 an inner rotor rotatable about a first axis, said inner rotor having a series of slots;   a first vane received into one of said series of slots;   a second vane received into another of said series of slots;   a third vane received into another of said series of slots;   a fourth vane received into another of said series of slots;   each of said first vane, said second vane, said third vane, and said fourth vane having a first side, a second side, an extension, a third side having a flat engagement, and a fourth side having a flat engagement;   an outer rotor having a series of recesses, each of said series of recesses for receiving one of said flat engagement of said third side or said flat engagement of said fourth side, said outer rotor rotatable about a second axis;   an expandable chamber formed between said inner rotor and said outer rotor;   a housing having an inlet port and an outlet port; and   an eccentric ring which circumscribes said outer rotor and is located within said housing, said eccentric ring having a flange and a pivot hole, and said inner rotor rotates about said first axis, driving said first vane, said second vane, said third vane, and said fourth vane, and said outer rotor rotates about said second axis, causing said first vane, said second vane, said third vane, and said fourth vane to drive said series of recesses of said outer rotor, thereby rotating said outer rotor.   
   
   
       23 . The sliding vane pump which is used for pumping fluid of  claim 22 , further comprising a pivot pin formed as a portion of said housing, said pivot pin being disposed within said pivot hole such that said flange of said eccentric ring receives a force to cause said eccentric ring to pivot about said pivot pin, and the position of said inner rotor to change in relation to outer rotor. 
   
   
       24 . The sliding vane pump which is used for pumping fluid of  claim 22 , further comprising said first axis to be substantially aligned with said second axis to cause said first vane, said second vane, said third vane, and said fourth vane to remain stationary relative to said series of recesses. 
   
   
       25 . The sliding vane pump which is used for pumping fluid of  claim 22 , further comprising said first axis to be offset from said second axis to cause said expandable chamber, said first vane, said second vane, said third vane, and said fourth vane to transfer fluid from said inlet port to said outlet port. 
   
   
       26 . The sliding vane pump which is used for pumping fluid of  claim 22 , further comprising said first side of each of said first vane, said second vane, said third vane, and said fourth vane to be offset and parallel to said second side of each of said first vane, said second vane, said third vane, and said fourth vane. 
   
   
       27 . The sliding vane pump which is used for pumping fluid of  claim 25 , further comprising an angle between said flat engagement of said third side in relation to said first side and said second side, and said angle is also between said flat engagement of said fourth side in relation to said first side and said second side. 
   
   
       28 . The sliding vane pump which is used for pumping fluid of  claim 26 , further comprising said series of recesses to be positioned at said angle of said flat engagement of said third side and said flat engagement of said fourth side. 
   
   
       29 . The sliding vane pump which is used for pumping fluid of  claim 22 , further comprising said first vane, said second vane, said third vane, and said fourth vane are stacked such that said extension of said first vane is adjacent to said extension of said second vane, said extension of said second vane is adjacent to said extension of said first vane and said extension of said third vane, said extension of said third vane is adjacent to said extension of said second vane and said extension of said fourth vane, and said extension of said fourth vane is adjacent to said extension of said third vane. 
   
   
       30 . The sliding vane pump which is used for pumping fluid of  claim 22 , wherein said inner rotor is a straddle support inner rotor, comprising:
 a first hub portion;   a plurality of vane supports, said first hub portion being connected to said plurality of vane supports;   a second hub portion, said second hub portion being connected to said plurality of vane supports on the opposite side of said plurality of vane supports in relation to said first hub portion; and   two of said series of slots further comprise at least two elongated slots, wherein said first vane is inserted through one of said at least two elongated slots, and said fourth vane is inserted through another of said at least two elongated slots.   
   
   
       31 . The sliding vane pump which is used for pumping fluid of  claim 22 , each of said second vane and said third vane further comprising:
 a multi-piece vane divided along said extension, wherein said multi-piece vane is inserted into one of said series of slots.   
   
   
       32 . The sliding vane pump which is used for pumping fluid of  claim 22 , further comprising:
 a piston having a substantially flat portion and a hollow portion;   a recess formed as a portion of said piston, said recess receiving a portion of said flange of said eccentric ring; and   a return spring partially disposed in said hollow portion, and in contact with a portion of said housing such that said return spring biases said piston to locate said flange of said eccentric ring and said eccentric ring position said first axis substantially in alignment with said second axis, and said first axis will become offset from said second axis when a force is applied to said flat portion of said piston that is greater than the force applied to said piston by said return spring.