US3619093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gear-type hydraulic machine
Assignee: FURSTLICH HOHENZOLLERNSCHE HUTTENVERWATTUNG LAUCHERTHAL
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Filing: 1969-11-13
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Granted: 1971-11-09
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Expires: 1989-11-13
Abstract
Abstract A gear-type hydraulic machine, wherein fluid is conveyed between gear teeth of two mating gearwheels, includes an internal gear rotatably mounted in the machine and a smaller inner external gear mounted in the machine on journals and meshing with the internal gear. The pressure and the suction sides formed between the cooperating gear teeth are separated exclusively by the mating or meshing teeth. The numbers of teeth of the two gears differ sufficiently that a substantial part of the gear peripheries run out of engagement to define a crescent-shaped zone between the gears. This crescent-shaped zone communicates, through suitably dimensioned leakage passages or gaps, with the respective pressure and suction sides of the machine in order for intermediate pressure to build up in the crescent-shaped zone. This intermediate pressure operates to reduce substantially the radial thrust applied to the smaller inner gear by the pressure on the pressure side.
Inventors
- 👤 Hermann Harle
- 👤 Siegfried Eisenmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:21
CPC Classifications
F; F04; F04C; F04C14/00; F04C14/04; F04C14/08; F04C15/00; F04C15/0057; F04C15/0061; F04C2/00; F04C2/08; F04C2/082; F04C2/084; F04C2/10; F04C2/102
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
167 words
In a gear-type hydraulic machine, wherein fluid is conveyed between gear teeth of two mating gearwheels, one of which is an internal gear rotatably mounted in the machine and the other of which is a smaller diameter inner external gear mounted in the machine on journals, and wherein the pressure side and the suction side, formed between the intermeshing teeth of the two gears, are separated solely by the mating teeth: the improvement comprising the numbers of teeth of said two gears differing sufficiently for a substantial part of the gear peripheries to run out of engagement with each other to define a crescent-shaped zone between said gears and in which the gear teeth are not in engagement; and suitably dimensioned leakage paths connecting said crescent-shaped zone with the pressure side and with the suction side to build up, in said crescent-shaped zone, an intermediate pressure operating substantially to reduce the radial thrust applied to said smaller diameter inner gear by the pressure on the pressure side.
Claim 2
Dependent Claim
167 words
In a gear-type hydraulic machine, wherein fluid is conveyed between gear teeth of two mating gearwheels, one of which is an internal gear rotatably mounted in the machine and the other of which is a smaller diameter inner external gear mounted in the machine on journals, and wherein the pressure side and the suction side, formed between the intermeshing teeth of the two gears, are separated solely by the mating teeth: the improvement comprising the numbers of teeth of said two gears differing sufficiently for a substantial part of the gear peripheries to run out of engagement with each other to define a crescent-shaped zone between said gears and in which the gear teeth are not in engagement; and suitably dimensioned leakage paths connecting said crescent-shaped zone with the pressure side and with the suction side to build up, in said crescent-shaped zone, an intermediate pressure operating substantially to reduce the radial thrust applied to said smaller diameter inner gear by the pressure on the pressure side.
Claim 3
Dependent Claim
84 words
In a gear-type hydraulic machine, the improvement claimed in claim 1, in which the fluid inlet and fluid outlet regions are separated peripherally, by at least a half tooth division, from the point where the pitch circles of said two gears make contact; at least one of said fluid inlet and fluid outlet regions extending peripherally, in a direction away from said point, to a point that is spaced slightly less than one tooth division from the adjacent peripheral end of said crescent-shaped zone.
Claim 4
Dependent Claim
18 words
In a gear-type hydraulic machine, the improvement claimed in claim 1, wherein said machine is a gear pump.
Claim 5
Dependent Claim
16 words
In a gear-type hydraulic machine, the improvement claimed in claim 1, wherein said machine is reversible.
Claim 6
Dependent Claim
51 words
In a gear-type hydraulic machine, the improvement claimed in claim 4, in which said machine has inLet and outlet ports; the space in which said gears revolve, including said inlet and outlet ports, having a symmetrical configuration with reference to a symmetry plane including the axes of rotation of said gears.
Claim 7
Dependent Claim
29 words
In a gear-type hydraulic machine, the improvement claimed in claim 1, in which said internal gear has gear teeth with circular arc tooth flanks meeting at a common tip.
Claim 8
Dependent Claim
27 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which said tooth flanks meet at said tip at an angle of 80* to 140*.
Claim 9
Dependent Claim
27 words
In a gear-type hydraulic machine, the improvement claimed in claim 7, in which said tooth flanks meet at said tip at an angle of 100* to 110*.
Claim 10
Dependent Claim
46 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the radius of the circular arc of said tooth flanks of said internal gear is about from 75 percent to 90 percent of the radium of the addendum circle of said internal gear.
Claim 11
Dependent Claim
46 words
In a gear-type hydraulic machine, the improvement claimed in claim 9, in which the radium of the circular arc of said tooth flanks of said internal gear is about from 80 percent to 85 percent of the radium of the addendum circle of said internal gear.
Claim 12
Dependent Claim
36 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the height of said teeth of said internal gear is approximately equal to half the pitch of said teeth of said internal gear.
Claim 13
Dependent Claim
51 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the width of the gaps between the teeth at the roots of said teeth of said internal gear is equal to about from 40 percent to 60 percent of the thickness of said teeth at the roots thereof.
Claim 14
Dependent Claim
31 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the shape of the external teeth of said inner gear is generated by rolling on said internal gear.
Claim 15
Dependent Claim
33 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the number of teeth of said internal gear is one more than the number of teeth of said inner gear.
Claim 16
Dependent Claim
33 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the number of teeth of said internal gear is two more than the number of teeth of said inner gear.
Claim 17
Dependent Claim
33 words
In a gear-type hydraulic machine, the improvement claimed in claim 6, in which the relatively remote tooth flanks of adjacent gear teeth of said internal gear from parts of a common cylinder surface.
Claim 18
Dependent Claim
123 words
In a gear-type hydraulic machine, the improvement claimed in claim 1, including a casing in which said gears are rotatably mounted, said casing having a sidewall member engaging corresponding first sides of said gears; a thrust member mounted in said casing and engaging corresponding second sides of said gears; at least one of said members being formed with annular grooves communicating with the clearances at the side faces of said gears, to collect fluid forced into said clearances; said casing and said thrust member having bearing recesses defining, with said gears, hydraulic bearing recesses; ducts communicating with said hydraulic recesses; and bores connecting said annular grooves to said ducts to supply the collected fluid to said hydraulic bearing recesses at a limited pressure.
Claim 19
Dependent Claim
26 words
In a gear-type hydraulic machine, the improvement claimed in claim 17, in which said bores include bores extending radially of said wall member of said casing.
Claim 20
Dependent Claim
23 words
In a gear-type hydraulic machine, the improvement claimed in claim 17, in which said bores include bores extending axially of said internal gear.
Claim 21
Dependent Claim
90 words
In a gear-type hydraulic machine, the improvement claimed in claim 17, including a cover plate secured to said casing and engaging with the outer side of said thrust member; said outer side of said thrust member being formed with pressurized areas defined by O-rings, for urging said thrust member against the second sides of said gears; and axial ducts formed in said thrust member and connecting said pressurized areas with working chambers, inlet and outlet ports, or said crescent-shaped zone of said machine then axially aligned with said pressurized areas.
Claim 22
Dependent Claim
20 words
In a gear-type hydraulic machine, the improvement claimed in claim 17, including a pressure relief valve communicating with said bores.
Claim 23
Dependent Claim
20 words
In a gear-type hydraulic machine, the improvement claimed in claim 20, including a pressure-equalizing device communicating with said crescent-shaped zone.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |