US5073082A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic screw pump
Assignee: Individual
•
Filing: 1990-04-16
•
Granted: 1991-12-17
•
Expires: 2010-04-16
Abstract
Abstract In a hydraulic screw pump, a sealing element for the peripheral edge of the rotary screw. The sealing element is formed with a channel along its length to fit over this edge of the rotary screw. The channel may be varied in depth to adjust the gap between the rotary screw and a water-carrying trough for the pump. The width of the channel may also be adjusted to accommodate rotary screws of varying thicknesses. The sealing element, thus, retains the desired width of the gap even though the edges of the rotary screw are chipped or worn away.
Inventors
- 👤 Karl-August Radlik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:33
CPC Classifications
F; F04; F04B; F04B19/00; F04B19/08; F04B19/12; F04D; F04D29/00; F04D29/18; F04D29/181; F04D3/00; F04D3/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
83 words
A hydraulic screw pump for feeding waste water comprising: a screw body; a rotary screw helically attached to the screw body; a trough, the screw body being positioned in relation to the trough to form a gap of fixed width between an outer periphery of the rotary screw and the trough; and a sealing element attached to the outer periphery of the rotary screw along its entire length, the dimensions of the sealing element being such as to maintain the gap width constant.
Claim 2
Dependent Claim
83 words
A hydraulic screw pump for feeding waste water comprising: a screw body; a rotary screw helically attached to the screw body; a trough, the screw body being positioned in relation to the trough to form a gap of fixed width between an outer periphery of the rotary screw and the trough; and a sealing element attached to the outer periphery of the rotary screw along its entire length, the dimensions of the sealing element being such as to maintain the gap width constant.
Claim 3
Dependent Claim
52 words
The hydraulic screw pump of claim 1, wherein the sealing element includes a channel extending along the length of the sealing element, the depth of the channel being dimensioned to receive the outer periphery of the rotary screw and maintain the gap constant even where the diameter of the rotary screw varies.
Claim 4
Dependent Claim
23 words
The hydraulic screw pump of claim 1, in which the sealing element is adapted to accommodate any varying thicknesses of the rotary screw.
Claim 5
Dependent Claim
30 words
The hydraulic screw pump of claim 3, wherein the sealing element includes a channel extending along its length, the channel adapted to accommodate the greatest thickness of the rotary screw.
Claim 6
Dependent Claim
28 words
The hydraulic screw pump of claim 1, wherein the sealing element is placed on the outer periphery of the rotary screw after the screw body is ready made.
Claim 7
Dependent Claim
51 words
The hydraulic screw pump of claim 1, wherein the sealing element is formed of a thermoplastic, the sealing element placed on the rotary screw in an elastic condition, thereafter to be permanently affixed to the rotary screw through plastic deformation of the sealing element by means of heat and subsequent cooling.
Claim 8
Dependent Claim
20 words
The hydraulic screw pump of claim 6, wherein the sealing element is manufactured by the treatment of a semi-finished material.
Claim 9
Dependent Claim
44 words
The hydraulic screw pump of claim 6, wherein cavities in the sealing element resulting from variations in the diameter of the rotary screw are filled with plastic material to assure proper fit of the sealing element along the entire length of the rotary screw.
Claim 10
Dependent Claim
38 words
The hydraulic screw pump of claim 1, wherein the sealing element comprises a casting resin coated onto the peripheral edges of the rotary screw by use of a movable casting mold and adhering after setting of the resin.
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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) | 1994-12-16 | 1995-06-17 | 1995-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-16 | 1999-06-17 | 1999-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-16 | 2003-06-17 | 2003-12-17 | $7700.00 | Window Closed / Lapsed |