US3907470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gear machine
Assignee: HOHENZOLLERN HUETTENVERWALT
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Filing: 1973-12-26
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Granted: 1975-09-23
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Expires: 1993-12-26
Abstract
Abstract A gear machine (either a pump or a motor) having a housing, an internally-toothed, annular gear wheel rotatably positioned in the housing and having from 9 to 15 teeth, an externally-toothed pinion adapted to mesh with the annular gear wheel and having two teeth less than the annular gear wheel, the diameter of the addendum circle of the annular gear wheel being smaller than the diameter of the addendum circle of the pinion, and a generally crescent-shaped filler piece radially filling and extending over a predominant portion of the length of the free space between the addendum circle surface of the pinion and the addendum circle surface of the annular gear wheel on the side of the machine opposite the point of deepest tooth mesh of the pinion and the annular gear wheel, the filler piece having one cylindrical surface, on the annular gear wheel side thereof, defined by the addendum circle surface of the annular gear wheel and its other cylindrical surface, on the pinion side thereof, defined by the addendum circle surface of the pinion, whereby the addendum surfaces of the annular gear wheel and the pinion sealably glide along the corresponding cylindrical surfaces of the filler piece and at least the end of the filler piece which is pointing in the direction of rotation is shortened and terminates at a point at which the trailing end of the addendum surface of each tooth of the annular gear wheel comes out of contact with the corresponding cylindrical surface of the filler piece simultaneously with the trailing end of the addendum surface of one tooth of the pinion. The outermost flanks of two adjacent teeth of the annular gear wheel are defined by a circular arc or an arc of a curve equidistant from a hypocycloid. In the latter case, the ratio of the diameter of the rolling circle to the diameter of the fixed circle, by which the hypocycloid is generated, is an aliquant fraction in which the denominator of the fraction is equal to the number of teeth of the annular gear wheel and the numerator of the fraction is at least two and not more than the number of teeth in the annular gear wheel minus two.
Inventors
- 👤 Hermann Harle
- 👤 Siegfried Eisenmann
- 👤 Kurt Sickinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:02
CPC Classifications
F; F01; F01C; F01C1/00; F01C1/08; F01C1/082; F01C1/084; B; B23; B23F; B23F15/00; B23F15/08; B23F23/00; B23F23/12; B23F23/1293; F01C1/10; F01C1/102
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
264 words
A gear machine comprising a housing, an internally-toothed, annular gear wheel rotatably positioned in said housing and having from 9 to 15 teeth, an externally-toothed pinion adapted to mesh with said annular gear wheel and having two teeth less than said annular gear wheel, the diameter of the addendum circle of said annular gear wheel being smaller than the diameter of the addendum circle of said pinion, and a generally crescent-shaped filler piece radially filled and extending over a predominant portion of the length of the free space between the addendum circle surface of said pinion and the addendum circle surface of said annular gear wheel on the side of said machine opposite the point of deepest tooth mesh of said pinion and said annular gear wheel, said filler piece having one cylindrical surface, on the annular gear wheel side thereof, defined by said addendum circle surface of said annular gear wheel and its other cylindrical surface, on the pinion side thereof, defined by said addendum circle surface of said pinion; whereby said addendum surfaces of said annular gear wheel and said pinion sealably glide along said cylindrical surfaces of said filler piece, respectively, and at least the end of said filler piece which is pointing in the direction of rotation is shortened and terminates substantially at a position at which the trailing end of said addendum surface of one tooth of said annular gear wheel and the trailing end of said addendum surface of one tooth of said pinion simultAneously come out of contact with the corresponding cylindrical surfaces of said filler piece.
Claim 2
Dependent Claim
264 words
A gear machine comprising a housing, an internally-toothed, annular gear wheel rotatably positioned in said housing and having from 9 to 15 teeth, an externally-toothed pinion adapted to mesh with said annular gear wheel and having two teeth less than said annular gear wheel, the diameter of the addendum circle of said annular gear wheel being smaller than the diameter of the addendum circle of said pinion, and a generally crescent-shaped filler piece radially filled and extending over a predominant portion of the length of the free space between the addendum circle surface of said pinion and the addendum circle surface of said annular gear wheel on the side of said machine opposite the point of deepest tooth mesh of said pinion and said annular gear wheel, said filler piece having one cylindrical surface, on the annular gear wheel side thereof, defined by said addendum circle surface of said annular gear wheel and its other cylindrical surface, on the pinion side thereof, defined by said addendum circle surface of said pinion; whereby said addendum surfaces of said annular gear wheel and said pinion sealably glide along said cylindrical surfaces of said filler piece, respectively, and at least the end of said filler piece which is pointing in the direction of rotation is shortened and terminates substantially at a position at which the trailing end of said addendum surface of one tooth of said annular gear wheel and the trailing end of said addendum surface of one tooth of said pinion simultAneously come out of contact with the corresponding cylindrical surfaces of said filler piece.
Claim 3
Dependent Claim
96 words
A gear machine in accordance with claim 1 wherein the end edges of the cylindrical surfaces of the filler piece pointing in the direction of rotation terminate substantially on a plane parallel to the axes of the annular gear wheel and the pinion and passing through a point midway between said axes of said annular gear wheel and said pinion; said plane being further passed by the trailing end of the addendum surface of each tooth of said pinion simultaneously with the trailing end of the addendum surface of a tooth of said annular gear wheel.
Claim 4
Dependent Claim
72 words
A gear machine in accordance with claim 1 wherein the trailing end of the addendum surface of a tooth of the pinion passes the trailing end of a fluid opening in the housing after it has overtaken the leading end of the addendum surface of a tooth of the annular gear wheel which has, simultaneously with said tooth of said pinion, come out of contact with the end of the filler piece.
Claim 5
Dependent Claim
21 words
A gear machine in accordance with claim 1 wherein both ends of the filler piece are shortened by the same amount.
Claim 6
Dependent Claim
28 words
A gear machine in accordance with claim 1 wherein the outermost flanks of two neighboring teeth of the annular gear wheel are defined by a common circular arc.
Claim 7
Dependent Claim
16 words
A gear machine in accordance with claim 1 wherein the annular gear wheel has eleven teeth.
Claim 8
Dependent Claim
16 words
A gear machine in accordance with claim 1 wherein the annular gear wheel has nine teeth.
Claim 9
Dependent Claim
26 words
A gear machine in accordance with claim 1 wherein the filler piece is fixedly seated in at least one of the end walls of the housing.
Claim 10
Dependent Claim
24 words
A gear machine in accordance with claim 1 wherein the filler piece is fixedly seated in both of the end walls of the housing.
Claim 11
Dependent Claim
16 words
A gear machine in accordance with claim 1 wherein the pinion is provided with axially-disposed passages.
Claim 12
Dependent Claim
30 words
A gear machine in accordance with claim 1 wherein at least the effective portions of the tooth flanks of the annular gear wheel and the pinion are hardened and ground.
Claim 13
Dependent Claim
39 words
A gear machine in accordance with claim 1 which includes a drive shaft operatively coupled to the pinion, a fluid inlet and a fluid outlet and the shortened end of the filler piece is located adjacent said outlet opening.
Claim 14
Dependent Claim
39 words
A gear machine in accordance with claim 1 which includes a driven shaft operatively coupled to the pinion, a fluid inlet and a fluid outlet and the shortened end of the filler piece is located adjacent said inlet opening.
Claim 15
Dependent Claim
42 words
A gear machine in accordance with claim 1 wherein said machine is symmetrical with respect to a plane of symmetry through the axis of the annular gear wheel and the axis of the pinion, whereby the operation of said machine is reversible.
Claim 16
Dependent Claim
54 words
A gear machine in accordance with claim 1 wherein the filler piece is provided with a pair of projections, extending from at least one side and along about one-third of each end of said filler piece, and said projections are fixedly seated in complementary openings in at least one end wall of the housing.
Claim 17
Dependent Claim
31 words
A gear machine in accordance with claim 15 wherein the projections extend from both sides of the filler piece and are seated in openings in both end walls of the housing.
Claim 18
Dependent Claim
45 words
A gear machine in accordance with claim 1 wherein at least one edge of the teeth of the pinion has a shallow cut-out portion extending along the addendum surface thereof and forming a sharp-edged shoulder at a point along the length of said addendum surface.
Claim 19
Dependent Claim
22 words
A gear machine in accordance with claim 16 wherein the cut-out portion has a radial dimension of a fraction of a millimeter.
Claim 20
Dependent Claim
36 words
A gear machine in accordance with claim 1 wherein the diameter of the addendum circle of the pinion is 0.5 to 0.8 modules greater than the diameter of the addendum circle of the annular gear wheel.
Claim 21
Dependent Claim
34 words
A gear machine in accordance with claim 19 wherein the diameter of the addendum circle of the pinion is 0.7 modules greater than the diameter of thE addendum circle of said annular gear wheel.
Claim 22
Dependent Claim
19 words
A machine in accordance with claim 1 wherein the teeth of the annular gear wheel have a trochoidal form.
Claim 23
Dependent Claim
40 words
A gear machine in accordance with claim 21 wherein the diameter of the addendum circle of the pinion is at least one annular gear wheel tooth height smaller than the diameter of the dedendum circle of the annular gear wheel.
Claim 24
Dependent Claim
121 words
A gear machine in accordance with claim 21 wherein at least the effective portions of the tooth flanks of the annular gear wheel are defined by a curve equidistant from a hypocycloid and wherein the ratio of the diameter of the rolling circle to the diameter of the fixed circle, by which the hypocycloid is generated, is an aliquant fraction whose denominator is equal to the number of teeth of the annular gear wheel and whose numerator is at least two and not more than the number of teeth of the annular gear wheel minus two and the effective tooth flanks of the pinion are at least approximately determined by the rolling off of the pinion in the annular gear wheel.
Claim 25
Dependent Claim
142 words
A gear machine in accordance with claim 21 wherein the effective portions of the tooth flanks of the pinion are determined by rolling off of the pinion in an auxilliary, annular gear wheel, having effective tooth flanks defined by circular arcs, said circular arcs touch the tooth flanks of the annular gear wheel, which actually meshes with the pinion, at least approximately at the addendum, the radii of the circular arcs are at least equal to or slightly larger than the radius of curvature of the equidistant curve at the point of contact, the effective portions of the outermost tooth flanks of two adjacent teeth of said auxilliary, annular gear wheel, which face the tips of the cycloidal arc that enclose the same, are defined by said circular arcs and the effective portions of the tooth flanks of said pinion are ground.
Claim 26
Dependent Claim
30 words
A gear machine in accordance with claim 21 wherein the number of teeth of the annular gear wheel and the number of teeth of the pinion have no common divider.
Claim 27
Dependent Claim
73 words
A gear machine in accordance with claim 21 wherein one of the left-hand tooth flanks and right-hand tooth flanks of the annular gear wheel is defined by a first curve equidistant from a first hypocycloid and the other of said left-hand and right-hand tooth flanks is defined by an equidistant curve from a second, like hypocycloid angularly displaced from said first hypocycloid said hypocycloids having a common center and rotating against one another.
Claim 28
Dependent Claim
52 words
A gear machine in accordance with claim 26 wherein the distance of the equidistant curve from the hypocycloid is slightly less than half the linear distance between the ground portions of facing flanks of a pair of neighboring teeth of the annular gear wheel at the point where said portions are closest.
Claim 29
Dependent Claim
45 words
A gear machine in accordance with claim 26 wherein the distance between two facing tooth flanks of a pair of neighboring teeth of the annular gear wheel at the fixed circle is approximately equal to the width of a tooth flank at said fixed circle.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |