Stepped hollow wheel

Abstract

A gear set for an internal gear machine. Both front areas of the first gearwheel include respectively one running area, which are axially spaced apart by a first gearwheel thickness, and the second gearwheel includes a thickness-reduced region which has a reduced gearwheel thickness in relation to the first gearwheel thickness.

1 . A gear set for an internal gear machine, formed of two gearwheels each having two axial front areas,
 wherein both front areas of the first gearwheel comprise respectively one running area, which are axially spaced apart by a first gearwheel thickness, and   wherein the second gearwheel comprises a thickness-reduced region which has a gearwheel thickness that is reduced in relation to the first gearwheel thickness.   
     
     
         2 . The gear set according to  claim 1 , wherein
 the thickness-reduced region of the second gearwheel is a planar region, and/or   both surfaces of the thickness-reduced region of the second gearwheel respectively have the greatest axial height of the respective front area, and/or   the thickness-reduced region extends over the entire second gearwheel, and/or   a thickness reduction of the thickness-reduced region is in a range between 2 μm and 50 μm or between 3 μm and 30 μm or between 4 μm and 10 μm.   
     
     
         3 . The gear set according to  claim 1 , wherein both front areas of the second gearwheel comprise a surface of the thickness-reduced region and a running area or consist thereof,
 wherein the running areas of the two front areas of the second gearwheel are axially spaced apart by the first gearwheel thickness, and wherein
 the running areas respectively have the greatest axial height of the respective front area, and/or 
 the thickness-reduced region of the second gearwheel is a planar region, and/or 
 a thickness reduction of the thickness-reduced region amounts to at least 2, 4, 6, 10, 50, 100, 200 or 500 μm or is in a range between 2 μm and 50 μm or between 3 μm and 30 μm or between 4 μm and 10 μm, and/or 
 an axial height difference between the surface of the thickness-reduced region and the running area is identical on both front areas and/or amounts to one half of the thickness reduction. 
   
     
     
         4 . The gear set according to  claim 1 , wherein
 on one or both front area(s) of the first gearwheel the running area respectively has the greatest axial height of the respective front area, and/or   one or both front area(s) of the first gearwheel consist of the respective running area, or   the first gearwheel comprises a thickness-reduced region, so that the front areas of the first gearwheel comprise the respective running area and a surface of the thickness-reduced region or consist thereof, wherein preferably   the thickness-reduced region of the first gearwheel is a planar region, and/or   a thickness reduction of the thickness-reduced region amounts to at least 2, 4, 6, 10, 50, 100, 200 or 500 μm or is in a range between 2 μm and 50 μm or between 3 μm and 30 μm or between 4 μm and 10 μm, and/or   an axial height difference between the surface of the thickness-reduced region and the running area on both front areas is identical and/or amounts to one half of the thickness reduction.   
     
     
         5 . The gear set according to  claim 1 , wherein
 both running areas of the first gearwheel respectively have the greatest axial height of the respective front area and preferably both running areas respectively form the front areas of the first gearwheel, and   the thickness-reduced region of the second gearwheel is a planar, thickness-reduced region, the frontal surfaces of which respectively have the greatest axial height and/or respectively form the front areas of the second gearwheel, and   
       wherein preferably a thickness reduction is in a range between 2 μm and 50 μm or between 3 μm and 30 μm or between 4 μm and 10 μm. 
     
     
         6 . The gear set according to  claim 1 , wherein
 the running areas on one gearwheel or respectively on both gearwheels are arranged in the axial direction in overlapping manner and/or congruently or mirror-symmetrically and/or the first gearwheel thickness is present continuously in the overlap region and/or on the entire running area(s), and/or   the first gearwheel thickness is the maximal thickness of the respective gearwheel or of the gear set, and/or   one or each running area is continuously rotationally symmetric or discretely rotationally symmetric and/or   one or each running area comprises the front areas of the gearwheel teeth.   
     
     
         7 . The gear set according to  claim 1 , wherein
 the first and/or the second gearwheel is configured to be mirror-symmetric and/or has an n-fold discrete rotational symmetry with reference to the rotation axis, wherein n is the number of teeth of the gearwheel.   
     
     
         8 . The gear set according to  claim 1 , wherein at least one or all running areas and/or planar surfaces of thickness-reduced regions are grinded surfaces and/or have constant axial heights. 
     
     
         9 . The gear set according to  claim 1 , wherein the first gearwheel is the inner sprocket and the second gearwheel is the hollow wheel or the first gearwheel is the hollow wheel and the second gearwheel is the inner sprocket. 
     
     
         10 . The gear set according to  claim 1 , wherein the first and/or second gearwheel is configured in one-piece or single-piece manner and/or the first and second gearwheel consist of different materials or of the same material. 
     
     
         11 . The gear set according to  claim 1 , wherein
 the inner sprocket has a diameter between 5 and 100 mm, in particular of 30 mm, and has 10 to 30 teeth, in particular 15 teeth, and/or   the hollow wheel has an outer diameter between 20 and 150 mm, in particular of 52 mm, an inner diameter between 10 and 140 mm, in particular 40 mm, and has 12 to in particular 20 teeth, and/or   the ratio of the number of teeth of the inner sprocket to the hollow wheel amounts to between 2:3 and 4:5 and in particular is 3:4, and/or   the first gearwheel thickness is between 5 and 50 mm and in particular amounts to 13 mm.   
     
     
         12 . An internal gear machine, comprising:
 a gear set according to  claim 1 , and   axial sealing elements, in particular one or two axial sealing disks or axial housing parts, and preferably further comprising   a housing with hydraulic connectors, and/or   a hydraulic fluid, in particular a gear oil and/or Pentosin CHF 11S and/or with a viscosity between 500 and 3×10 −6  m 2 /s in a temperature range between −30° C. and 150° C.   
     
     
         13 . A motor-pump unit, comprising:
 an internal gear machine according to  claim 12 , and   a shaft which connects the inner sprocket to a motor,   wherein the motor-pump unit is preferably adapted for reversing operation and/or the motor is an electric motor generator.   
     
     
         14 . A method for manufacturing a gear set according to  claim 1 , comprising the steps of:
 supplying the first and the second gearwheel, the axial front areas of which comprise respectively one running area or consist thereof, wherein the running areas are axially spaced apart by the first gearwheel thickness and wherein preferably the supplying takes place through joint frontal grinding of both gearwheels, and   grinding in certain regions or over the full area of the second gearwheel for configuring the thickness-reduced region of the second gearwheel.   
     
     
         15 . The method according to  claim 14 , comprising the further step of grinding in certain regions of the first gearwheel for configuring the thickness-reduced region of the first gearwheel.