Displacement pump with variable volume flow

Abstract

A displacement pump with variable volume flow having a casing; a chamber with an inlet opening on a low pressure side and an outlet opening on a high pressure side for a fluid; an internal rotor capable of rotation about a rotational axis (D I ); a ring having a central ring axis (D A ) surrounding the internal rotor and forming together with the ring, at least one delivery cell in which fluid is delivered from a low pressure side to a high pressure side of the pump; and an adjusting device which, during an adjusting movement, rolls off on the casing without slipping is provided. The internal rotor is fixed to the adjusting device and rotatble about the rotational axis (D I ), and the position of the rotational axis (D I ) relative to the central ring axis (D A ) of the ring is adjusted by the adjusting movement of the adjusting device.

1 . A displacement pump with variable volume flow, comprising: 
 a.) a casing;    b.) a chamber defined by the casing and which comprises an inlet opening on a low pressure side and an outlet opening on a high pressure side for a fluid;    c.) an internal rotor which is accommodated in the chamber and can be rotated about a rotational axis (D I );    d.) a ring which is accommodated in the chamber, has a central ring axis (D A ), surrounds the internal rotor and forms, together with the ring, in the case of rotary driving, at least one delivery cell in which the fluid is delivered from the low pressure side to the high pressure side; and    e.) an adjusting device which, during an adjusting movement, rolls off on the casing without slipping, wherein 
 i.) the internal rotor is fixed to the adjusting device such that it can be rotated about the rotational axis (D I ), and wherein  
 ii.) the position of the rotational axis (D I ) relative to the central ring axis (D A ) of the ring is adjusted by the adjusting movement of the adjusting device.  
   
   
   
       2 . The displacement pump as set forth in  claim 1 , wherein the adjusting device comprises a toothing which is in toothed engagement with a toothing of the casing during the adjusting movement.  
   
   
       3 . The displacement pump as set forth in  claim 2 , wherein the toothing of the adjusting device is a round-flank toothing.  
   
   
       4 . The displacement pump as set forth in  claim 2 , wherein a centre point of a flank circle of a tooth of the adjusting device toothing approximately describes a hypocycloid when rolling off on the casing.  
   
   
       5 . The displacement pump as set forth in  claim 1 , wherein the adjusting device is an adjusting plate.  
   
   
       6 . The displacement pump as set forth in  claim 1 , wherein the adjusting device is arranged axially adjacent to the internal rotor.  
   
   
       7 . The displacement pump as set forth in  claim 1 , wherein the adjusting device forms sealing stays to hydraulically partition the high pressure side from the low pressure side.  
   
   
       8 . The displacement pump as set forth in  claim 5 , wherein during the adjusting movement, cylindrical surfaces which roll off on each other are formed on the adjusting plate and on the casing.  
   
   
       9 . The displacement pump as set forth in  claim 5 , wherein a difference in the diameters of the casing and the adjusting plate, underlying the cylindrical surfaces, is twice an eccentricity (e) between the rotational axis (D I ) of the internal rotor and the ring axis (D A ).  
   
   
       10 . The displacement pump as set forth in  claim 1 , wherein at least one of a magnitude and a rotational angular position of an eccentricity (e) between the rotational axis (D I ) of the internal rotor and the central ring axis (D A ) of the ring is adjusted by the adjusting movement.  
   
   
       11 . The displacement pump as set forth in  claim 10 , wherein the magnitude of the eccentricity (e) is constant.  
   
   
       12 . The displacement pump as set forth in  claim 1 , wherein the adjusting device is adjusted by an adjusting force against the force of an elastic component.  
   
   
       13 . The displacement pump as set forth in  claim 12 , wherein the adjusting force is formed from at least one of two hydraulic adjusting forces which act on the adjusting device and the internal rotor.  
   
   
       14 . The displacement pump as set forth in  claim 1  further comprising an elasticity plane spanned by the rotational axis (D I ) and the ring axis (D A ), wherein the elasticity plane is rotated about the ring axis (D A ) by a rotational angle which is a multiple of the rotational angle of the adjusting device arising as a result of rolling off.  
   
   
       15 . The displacement pump as set forth in  claim 1  further comprising an amount of fluid delivered by the displacement pump which increases roughly in proportion to a fluid pressure with which the adjusting device is charged.  
   
   
       16 . The displacement pump as set forth in  claim 1 , wherein a pressure of the fluid of the high pressure side of the pump is tapped at a location outside the displacement pump and the adjusting device is charged with the pressure in order to vary the volume flow.  
   
   
       17 . The displacement pump as set forth in  claim 16 , wherein the pressure is tapped at a crankshaft main gallery of a motor.  
   
   
       18 . The displacement pump as set forth in  claim 1 , wherein the displacement pump is at least one of an internal gear pump, a pendulum slider pump, or a wing cell pump.  
   
   
       19 . A displacement pump with variable volume flow, comprising: 
 a.) a pump casing;    b.) a rotary-driven ring which is mounted in the pump casing and comprises an internal toothing;    c.) a rotatably mounted internal rotor which meshes with the ring and comprises an external toothing;    d.) a gear ring running set comprising the ring and the internal rotor, and having a difference in a number of teeth equal to at least one, wherein the teeth have a tooth shape with which a number of expanding and compressing delivery cells sealed against each other, arise by contact of tips of the teeth;    e.) inlet and outlet openings arranged in the casing adjacent the delivery cells which are partitioned from each other by sealing stays;    f.) wherein an angular position of an elasticity plane of the gear ring running set with respect to the casing is varied; and    g.) an adjusting device including at least one of a pitch circle or pitch circle segment which can be rolled off on at least one of a pitch circle or pitch circle segment of the casing without slipping, wherein 
 i.) the adjusting device is arranged on one side of the gear ring running set viewed axially, and  
 ii.) the internal rotor is fixed to the adjusting device such that it can be rotated about a rotational axis (D I ).  
   
   
   
       20 . The displacement pump as set forth in  claim 19 , wherein a difference between the adjusting device pitch circle diameter and the casing pitch circle diameter is equal to twice an eccentricity (e) of the gear ring running set.  
   
   
       21 . The displacement pump as set forth in  claim 19 , wherein the inlet and outlet openings are provided in the adjusting device and are partitioned from each other by sealing stays which substantially overlap with the inlet and outlet openings arranged in the casing.  
   
   
       22 . The displacement pump as set forth in  claim 19 , wherein the at least one pitch circles or pitch circle segments which roll off on each other without slipping are formed by pitch circles of an adjusting transmission formed by at least one of a complete or partial internal transmission.  
   
   
       23 . The displacement pump as set forth in  claim 22 , wherein the adjusting transmission has an eccentricity (e) which corresponds to an eccentricity between the ring and the internal rotor.  
   
   
       24 . The displacement pump as set forth in  claim 22 , wherein an inner cylinder guide is provided on the casing and an outer cylinder guide is provided on the adjusting device and the outer cylinder guide rolls off on the inner cylinder guide during the adjusting movement.  
   
   
       25 . The displacement pump as set forth in  claim 24 , wherein each cylinder guides have a constant radius of curvature, and a difference between two radii of the curvature is equal to an eccentricity (e) between the ring and the internal rotor.  
   
   
       26 . The displacement pump as set forth in  claim 19 , further comprising an internal transmission formed by an external toothing of the adjusting device and an internal toothing of the casing, wherein the internal toothing of the casing comprises at least one of a partial toothing or one tooth more than the external toothing of the adjusting device, and wherein a difference in the number of teeth of at least the partial toothing is circumferential.  
   
   
       27 . The displacement pump as set forth in  claim 19 , wherein the internal toothing in the casing is manufactured by a path-controlled HSC (high speed cutting) drill spindle.  
   
   
       28 . The displacement pump as set forth in  claim 1  further comprising a slaving disc shrunk onto a shaft forming a fixed rotational connection between a drive shaft of the pump and the ring, and wherein the slaving disc comprises an external toothing which is exactly fitted into the internal toothing of the ring, forming an axial and allowing axial movement.  
   
   
       29 . The displacement pump as set forth in  claim 1  further comprising a bearing journal of the internal rotor formed as a hollow shaft, wherein a size of the inner diameter of the hollow shaft is such that a drive shaft is connected rotationally fixedly to the ring and freely rotates in the hollow shaft despite the eccentric movement.  
   
   
       30 . The displacement pump as set forth in  claim 1  wherein a magnitude of the adjusting movement of the adjusting device is defined in accordance with the working pressure of the high pressure side of the pump by the characteristic of a variable spring.  
   
   
       31 . The displacement pump as set forth in  claim 30 , wherein the variable spring is formed as a screw pressure spring having a line of application arranged at a distance from the moment pivots (M 1 , M 2 ) of the adjusting device to generate the moment pivots (M 1 , M 2 ).  
   
   
       32 . The displacement pump as set forth in  claim 1 , wherein at least one of the internal rotor, the ring, and the adjusting device is manufactured in a powder metallurgical method.  
   
   
       33 . The displacement pump as set forth in  claim 28 , wherein the slave disk is rotationally and axially fixed by a gear shaft spline.  
   
   
       34 . The displacement pump as set forth in  claim 19 , wherein the difference in the number of teeth is exactly equal to one.