US4570849A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fan drive, particularly for cooling installation of vehicles
Assignee: Mahle Behr GmbH and Co KG
•
Filing: 1984-11-16
•
Granted: 1986-02-18
•
Expires: 2004-11-16
Abstract
Abstract Disclosed is a fan drive, in particular one for cooling installations of rail vehicles. The fan drive comprises a hydraulic motor and a control valve which regulates a bypass as a function of temperature, thus affecting the flow of a pressure medium driving the motor. The control valve comprises a control piston subjected to a control pressure in the direction of closing the bypass, and a counterbalancing pressure in the opposite direction from the source of the pressure medium. The control valve also comprises a control spring which biases the control piston in the direction of closing the valve, and a pilot valve which affects the control pressure. The pilot valve is actuated by an electromechanical servo component. The pilot valve is located in an insert which is arranged within the control piston. A central bore of the control piston is slidingly guided on the convex surface of the insert so as to form a seal.
Inventors
- 👤 Thomas Klaucke
- 👤 Franz Pigisch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:31
CPC Classifications
F; F01; F01P; F01P7/00; F01P7/02; F01P7/04; F01P7/044
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
263 words
A fan drive suitable for a cooling installation of a vehicle, comprising: (a) a hydraulic motor which is actuated by a pressure medium; (b) a bypass for detouring the flow of pressure medium around the hydraulic motor; (c) a control valve which regulates the flow of pressure medium to the bypass and to the hydraulic motor wherein said control valve comprises a control piston for opening and closing said bypass and having a central bore, an insert upon which the central bore of the control piston is slidingly arranged so as to form a seal, a front surface of the control piston facing the direction of closing said bypass which is acted upon by the pressure medium, a back surface of the control piston facing away from the direction of closing said bypass which is also acted upon by the pressure medium wherein the pressure acting on the front side of the control piston is the full pressure of the pressure medium called the high-pressure, and the pressure of the pressure medium acting on the back side of the control piston is called the control pressure, a control spring for biasing the control piston in the direction of closing said bypass, and a control cylinder for slidably containing the control piston which is divided by said piston into a high-pressure section in front of said front surface and a control chamber in back of said back surface; (d) a pilot valve, arranged in said insert, which functions to regulate said control pressure; and (e) an electromechanical servo element for actuating said pilot valve.
Claim 2
Dependent Claim
263 words
A fan drive suitable for a cooling installation of a vehicle, comprising: (a) a hydraulic motor which is actuated by a pressure medium; (b) a bypass for detouring the flow of pressure medium around the hydraulic motor; (c) a control valve which regulates the flow of pressure medium to the bypass and to the hydraulic motor wherein said control valve comprises a control piston for opening and closing said bypass and having a central bore, an insert upon which the central bore of the control piston is slidingly arranged so as to form a seal, a front surface of the control piston facing the direction of closing said bypass which is acted upon by the pressure medium, a back surface of the control piston facing away from the direction of closing said bypass which is also acted upon by the pressure medium wherein the pressure acting on the front side of the control piston is the full pressure of the pressure medium called the high-pressure, and the pressure of the pressure medium acting on the back side of the control piston is called the control pressure, a control spring for biasing the control piston in the direction of closing said bypass, and a control cylinder for slidably containing the control piston which is divided by said piston into a high-pressure section in front of said front surface and a control chamber in back of said back surface; (d) a pilot valve, arranged in said insert, which functions to regulate said control pressure; and (e) an electromechanical servo element for actuating said pilot valve.
Claim 3
Dependent Claim
25 words
A fan drive according to claim 1, wherein said control spring is supported on its side facing away from the control piston by the insert.
Claim 4
Dependent Claim
19 words
A fan drive according to claim 1, wherein the control valve is in the form of a seat valve.
Claim 5
Dependent Claim
19 words
A fan drive according to claim 1, wherein the control valve is in the form of a slide valve.
Claim 6
Dependent Claim
29 words
A fan drive according to claim 1, wherein said central bore extends over the entire length of the control piston, and wherein the insert projects through said central bore.
Claim 7
Dependent Claim
17 words
A fan drive according to claim 1, wherein the high pressure and the control pressure are counterbalanced.
Claim 8
Dependent Claim
16 words
A fan drive according to claim 1, wherein the electromechanical servo element comprises a control magnet.
Claim 9
Dependent Claim
16 words
A fan drive according to claim 1, wherein the electromechanical servo element comprises a step motor.
Claim 10
Dependent Claim
77 words
A fan drive according to claim 1, wherein the pilot valve is an analog valve, and wherein said pilot valve comprises: a valve cone having a tip; a valve seat onto which the valve cone fits so as to make a seal; a coil spring for biasing the valve cone against the valve seat; and a ball which interacts with the tip of the valve cone so as to lift the valve cone from the valve seat.
Claim 11
Dependent Claim
18 words
A fan drive according to claim 9, wherein the biasing force of the coil spring may be adjusted.
Claim 12
Dependent Claim
20 words
A fan drive according to claim 10, further comprising a screw for adjusting the biasing force of the coil spring.
Claim 13
Dependent Claim
34 words
A fan drive according to claim 10, further comprising a slidably introducable support element, which may be immobilized in any desired position and which serves to adjust the biasing force of the coil spring.
Claim 14
Dependent Claim
51 words
A fan drive according to claim 1, further comprising a first choke which connects the high-pressure section of said control cylinder with said control chamber; and a second choke which has a cross-section greater than the cross-section of the first choke and which connects said control chamber with said pilot valve.
Claim 15
Dependent Claim
27 words
A fan drive according to claim 1, wherein the control piston and the pilot valve are disposed in a connector or closure plate of a hydraulic motor.
Claim 16
Dependent Claim
15 words
A fan drive according to claim 1, wherein the hydraulic motor is a gear motor.
Claim 17
Dependent Claim
24 words
A fan drive according to claim 1, wherein the pilot valve is in its closed position when said electromechanical servo element is without power.
Claim 18
Dependent Claim
39 words
A fan drive according to claim 1, wherein said fan drive is incorporated into a liquid cooling system, and wherein said electromechanical servo element is actuated according to the temperature of a cooling medium in the liquid cooling system.
Claim 19
Dependent Claim
38 words
A fan drive according to claim 1, wherein said fan drive is incorporated into the cooling system of an electrical motor, and wherein said electromechanical servo element is actuated according to the temperature of an electrical motor winding.
Claim 20
Dependent Claim
31 words
A fan drive according to claim 3, wherein the surface area of said front surface exposed to pressure is equal to the surface area of said back surface exposed to pressure.
Claim 21
Dependent Claim
31 words
A fan drive according to claim 4, wherein the surface area of said front surface exposed to pressure is equal to the surface area of said back surface exposed to pressure.
References Cited (Backward Citations)
US2673706A
Cited
US2758811A
Cited
US2893680A
Cited
US3118648A
Cited
US3198204A
Cited
US3297047A
Cited
US3415269A
Cited
US3664129A
Cited
US4009860A
Cited
US4065052A
Cited
US4283009A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-17 | 1989-08-19 | 1990-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-17 | 1993-08-19 | 1994-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-17 | 1997-08-19 | 1998-02-18 | $7700.00 | Window Closed / Lapsed |