Patent US3924705A successfully refreshed from Google Patents.
US3924705A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power steering mechanism
Assignee: Aisin Corp
•
Filing: 1972-11-28
•
Granted: 1975-12-09
•
Expires: 1992-11-28
Abstract
Abstract A power steering mechanism for a vehicle comprising a fluid releasing mechanism interposed within a passage means communicating a pair of fluid chambers respectively arranged on opposite sides of a servo piston for controlling the fluid flow between said chambers and ultimately releasing the power steering function according to either or both increase of a vehicle speed and or a rotation angle of a steering wheel.
Inventors
- 👤 Masakazu Sugisawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:58
CPC Classifications
B; B62; B62D; B62D6/00
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
184 words
A power steering mechanism comprising, a housing provided with a cylinder, a piston fitted within said cylinder for axial sliding movement therein, operably connected to a steering wheel and defining a pair of opposed fluid chambers within said cylinder, a sector mounted within said cylinder for operative connection with steering road wheels of a vehicle and operatively connected to said piston, a reservoir for a fluid, a pump for the fluid, a changeover control valve for selectively connecting said reservoir through a first passageway to one of said fluid chambers and said pump through a second passageway to the other of said fluid chambers depending on the direction of turning of the steering wheel to provide an assist for turning said steering road wheels, a third passage means connecting said two fluid chambers together, at least one fluid control valve disposed within said third passage means, and means for opening said at least one fluid control valve in proportional response to increases in at least one operational characteristic of the vehicle while in motion to decrease the assist for turning the steering road wheels.
Claim 2
Dependent Claim
184 words
A power steering mechanism comprising, a housing provided with a cylinder, a piston fitted within said cylinder for axial sliding movement therein, operably connected to a steering wheel and defining a pair of opposed fluid chambers within said cylinder, a sector mounted within said cylinder for operative connection with steering road wheels of a vehicle and operatively connected to said piston, a reservoir for a fluid, a pump for the fluid, a changeover control valve for selectively connecting said reservoir through a first passageway to one of said fluid chambers and said pump through a second passageway to the other of said fluid chambers depending on the direction of turning of the steering wheel to provide an assist for turning said steering road wheels, a third passage means connecting said two fluid chambers together, at least one fluid control valve disposed within said third passage means, and means for opening said at least one fluid control valve in proportional response to increases in at least one operational characteristic of the vehicle while in motion to decrease the assist for turning the steering road wheels.
Claim 3
Dependent Claim
35 words
A power steering mechanism as claimed in claim 1 wherein said means for opening said at least one fluid control valve is proportionately responsive to an increase in the rotation angle of the steering wheel.
Claim 4
Dependent Claim
154 words
A power steering mechanism as claimed in claim 2 wherein said at least one fluid control valve includes a control cylinder sealably disposed in a bore in said housing and having opposed openings in the wall of said control cylinder opening into said third passage means for communication with said two chambers respectively, and a control piston slidably fitted in said control cylinder to control flow of the fluid between said opposed openings, one end of said control piston projecting from said cylinder, connecting rod means pivotally connected at one end to the projecting end of said control piston and at the other end to said sector, the other end of said control piston having a tapered cross-section, whereby said control piston gradually opens or closes communication between the opposed openings in said control cylinder wall to control flow of fluid through said third passage means proportionately to the rotational movement of said sector.
Claim 5
Dependent Claim
50 words
A power steering mechanism as claimed in claim 3 and further comprising means cooperating with the outer end of said control cylinder for adjusting the relative position of the opposed openings in the wall of the control cylinder in said bore with respect to said control piston and said housing.
Claim 6
Dependent Claim
55 words
A power steering mechanism as claimed in claim 4 wherein said outer end of said control cylinder extends outwardly from the bore in said housing and wherein said adjusting means comprises a nut member threadedly engaged with the outer end of said control cylinder for adjusting the position of said control cylinder in said bore.
Claim 7
Dependent Claim
62 words
A power steering mechanism as claimed in claim 4 and further comprising washer means disposed in the bottom of the bore in said housing for adjusting the position of said control cylinder in said bore and a nut member threadedly engaged with the inner surface of the outer end of said bore for locking said control cylinder in position in said bore.
Claim 8
Dependent Claim
91 words
A power steering mechanism as claimed in claim 1 wherein said at least one fluid control valve comprises a first control valve and a second control valve disposed in series in said third passage means, and said means for opening said at least one fluid control valve comprises a first means for opening said first control valve in proportional response to increase in the speed of the vehicle and a second means for opening said second control valve in proportional response to increases in the rotation angle of the steering wheel.
Claim 9
Dependent Claim
143 words
A power steering mechanism as claimed in claim 7 wherein said first control valve includes a control cylinder having two opposed openings in the wall thereof opening into said third passage means for communication with said two chambers respectively and a third opening at one end thereof, a control piston slidably mounted within said control cylinder and having a tapered groove along the outer periphery thereof, biasing means disposed between one end of said control piston and the other end of said control cylinder, and a pump actuated by the output of the vehicle engine for supplyinG pressurized fluid through said third opening to move said control piston against said biasing means, whereby said control piston gradually opens and closes communication between said two opposed openings to control flow of fluid through said third passage means proportionately to the speed of the vehicle.
Claim 10
Dependent Claim
151 words
A power steering mechanism as claimed in claim 8 wherein said second control valve includes a control cylinder sealably disposed in a bore in said housing and has opposed openings in the wall of said control cylinder opening into said third passage means for communication with said two chambers respectively, and a control piston slidably fitted in said control cylinder to control flow of the fluid between said opposed openings, one end of said control piston projecting from said cylinder, connecting rod means pivotally connected at one end to the projecting end of said control piston and at the other end to said sector, the other end of said control piston having a tapered cross-section, whereby said control piston gradually opens or closes communication between the opposed openings in said control cylinder wall to control flow of fluid through said third passage means proportionately to the rotational movement of said sector.
Claim 11
Dependent Claim
151 words
A power steering mechanism as claimed in claim 7 wherein said second control valve includes a control cylinder sealably disposed in a bore in said housing and having opposed openings in the wall of said control cylinder opening into said third passage means for communication with said two chambers respectively, and a control piston slidably fitted in said control cylinder to control flow of the fluid between said opposed openings, one end of said control piston projecting from said cylinder, connecting rod means pivotally connected at one end to the projecting end of said control piston and at the other end to said sector, the other end of said control piston having a tapered cross-section, whereby said control piston gradually opens or closes communication between the opposed openings in said control cylinder wall to control flow of fluid through said third passage means proportionately to the rotational movement of said sector.
Claim 12
Dependent Claim
178 words
A power steering mechanism comprising; a housing provided with a cylinder, a piston fitted within said cylinder for axial sliding movement therein, operably connected to a steering wheel and defining a pair of opposed fluid chambers within said cylinder, a sector mounted within said cylinder for operative connection with steering road wheels of a vehicle and operatively connected to said piston, a reservoir for a fluid, a pump for the fluid, a changeover control valve for selectively connecting said reservoir through a first passageway to one of said fluid chambers and said pump through a second passageway to the other of said fluid chambers depending on the direction of turning of the steering wheel to provide an assist for turning said steering road wheels, a third passage means connecting said two fluid chambers together, at least one fluid control valve disposed within said third passage means, and means for opening said at least one fluid control valve in proportional response to increases in the speed of the vehicle to decrease the assist for turning the steering road wheels.
Claim 13
Dependent Claim
178 words
A power steering mechanism comprising; a housing provided with a cylinder, a piston fitted within said cylinder for axial sliding movement therein, operably connected to a steering wheel and defining a pair of opposed fluid chambers within said cylinder, a sector mounted within said cylinder for operative connection with steering road wheels of a vehicle and operatively connected to said piston, a reservoir for a fluid, a pump for the fluid, a changeover control valve for selectively connecting said reservoir through a first passageway to one of said fluid chambers and said pump through a second passageway to the other of said fluid chambers depending on the direction of turning of the steering wheel to provide an assist for turning said steering road wheels, a third passage means connecting said two fluid chambers together, at least one fluid control valve disposed within said third passage means, and means for opening said at least one fluid control valve in proportional response to increases in the speed of the vehicle to decrease the assist for turning the steering road wheels.
Claim 14
Dependent Claim
143 words
A power steering mechanism as claimed in claim 11 wherein said fluid control valve includes a control cylinder having two opposed openings in the wall thereof opening into said third passage means for communication with said two chambers respectively and a third opening at one end thereof, a control piston slidably mounted within said control cylinder and having a tapered groove along the outer periphery thereof, biasing means disposed between one end of said control piston and the other end of said control cylinder, and a pump actuated by the output of the vehicle engine for supplying pressurized fluid through said third opening to move said control piston against saiD biasing means, whereby said control piston gradually opens and closes communication between said two opposed openings to control flow of fluid through said third passage means proportionately to the speed of the vehicle.
Claim 15
Dependent Claim
22 words
A power steering mechanism as claimed in claim 12, wherein said control cylinder is sealably disposed in a bore in said housing.
Claim 16
Dependent Claim
51 words
A power steering mechanism as claimed in claim 13 and further comprising means cooperating with the outer end of said control cylinder for adjusting the relative position of the two opposed openings in the wall of the control cylinder in said bore with respect to said control piston and said housing.
Claim 17
Dependent Claim
55 words
A power steering mechanism as claimed in claim 14 wherein the outer end of said control cylinder extends outwardly from the bore in said housing and wherein said adjusting means comprises a nut member threadedly engaged with the outer end of said control cylinder for adjusting the postion of said control cylinder in said bore.
Claim 18
Dependent Claim
62 words
A power steering mechanism as claimed in claim 14 and further comprising washer means disposed in the bottom of the bore in said housing for adjusting the position of said control cylinder in said bore and a nut member threadedly engaged with the inner surface of the outer end of the bore for locking said control cylinder in position in said bore.
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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |