Patent US3828894A successfully refreshed from Google Patents.
US3828894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telescopic piston for added brake wear adjustment
Assignee: Goodyear Tire and Rubber Co
•
Filing: 1972-12-27
•
Granted: 1974-08-13
•
Expires: 1992-12-27
Abstract
Abstract Disclosed is a telescopic brake piston and return mechanism which provides a means for compensating for the wear affectuated reduced thickness of the brake disk stack of an aircraft braking system. Fundamentally, the telesopic brake piston comprises two interfitting pistons received within a brake housing. The smaller of the two pistons brings the brake disks of the brake disk stack into frictional engagement with each other at which time the second piston causes the application of the working brake force. The smaller piston is provided with a sufficient travel distance to be capable of causing such frictional engagement regardless of reduced thickness of the brake disk stack due to wear. When the smaller piston causes such engagement and the second piston begins to apply the braking force, the smaller piston becomes sealed so as to constitute a solid hydraulic column. The telescopic return mechanism associated with the telescopic piston is such as to return the pressure plate of the brake disk stack a predetermined distance after each braking operation, such distance being independent of the amount of wear experienced in the brake disk stack. Consequently, the return mechanism guarantees that the free travel distance of the pressure plate will be consistent throughout the life of the brake disk stack. Fundamentally, this return mechanism comprises a slotted tubular threaded spring follower which receives a tubular threaded sleeve which in turn receives a still smaller slotted tubular threaded member. The various threads on the elements of the return mechanism interlock and provide the means for compensating for brake disk wear.
Inventors
- 👤 R Crossman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:09
CPC Classifications
F; F16; F16D; F16D65/00; F16D65/38; F16D65/40; F16D65/52; F16D65/54; F16D55/00; F16D55/24; F16D55/26; F16D55/36; F16D55/40; F16D65/14; F16D65/16; F16D65/18; F16D2055/0004; F16D2055/0058; F16D2121/00; F16D2121/02
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
204 words
A braking system associated with a brake system housing and the pressure plate of a brake disk stack, comprising: a telescopic brake piston subassembly fixedly attached to the brake system housing and in operative engagement with the pressure plAte, the piston subassembly comprising at least two pistons, a smaller piston slidably received within a larger piston, the larger piston being slidably received in a sleeve housing, and wherein a cavity exists between the two pistons, the cavity containing at least one spring in operative separating engagement between the two pistons and at least one spring in operative separating engagement between the smaller piston and a control probe, the control probe providing a valve to control the flow of braking fluid into and out of the cavity, the piston subassembly causing frictional engagement of the disks of the brake stack upon actuation thereof; and a telescopic return mechanism fixedly attached to the brake system housing and in operative engagement with the pressure plate such that upon release of the actuation of the piston subassembly the return mechanism acts to relieve the frictional engagement of the disks of the brake disk stack, the piston subassembly and return mechanism being operationally unaffected by brake disk stack wear.
Claim 2
Dependent Claim
204 words
A braking system associated with a brake system housing and the pressure plate of a brake disk stack, comprising: a telescopic brake piston subassembly fixedly attached to the brake system housing and in operative engagement with the pressure plAte, the piston subassembly comprising at least two pistons, a smaller piston slidably received within a larger piston, the larger piston being slidably received in a sleeve housing, and wherein a cavity exists between the two pistons, the cavity containing at least one spring in operative separating engagement between the two pistons and at least one spring in operative separating engagement between the smaller piston and a control probe, the control probe providing a valve to control the flow of braking fluid into and out of the cavity, the piston subassembly causing frictional engagement of the disks of the brake stack upon actuation thereof; and a telescopic return mechanism fixedly attached to the brake system housing and in operative engagement with the pressure plate such that upon release of the actuation of the piston subassembly the return mechanism acts to relieve the frictional engagement of the disks of the brake disk stack, the piston subassembly and return mechanism being operationally unaffected by brake disk stack wear.
Claim 3
Dependent Claim
47 words
The braking system as recited in claim 1, wherein the pistons and sleeve housing are characterized by the presence of complementary ring shoulders providing a means for restricting the motion of the smaller piston within the larger piston and of the larger piston within the sleeve housing.
Claim 4
Dependent Claim
77 words
The braking system as recited in claim 1, wherein the telescopic return mechanism comprises a plurality of progressively smaller inter-engaging tubular members, each such tubular member contained within the immediately larger tubular member, the largest such tubular member being received in a return mechanism casing, each of the tubular members having a plurality of threads thereon which are complementary to and in engagement with the plurality of the threads on each of the immediately adjacent tubular members.
Claim 5
Dependent Claim
58 words
The braking system as recited in claim 1 wherein the spring in operative engagement between the two pistons causes a biasing force against the larger piston so as to prevent any movement thereof within the sleeve housing until the hydraulic brake pressure with the braking system acting on the base of the larger piston reaches a predetermined level.
Claim 6
Dependent Claim
53 words
The braking system as recited in claim 1 wherein the spring in operative engagement between the smaller piston and the control probe presents a biasing force upon the control probe causing the control probe to engage with a valve seat when the larger piston has moved a predetermined distance within the sleeve housing.
Claim 7
Dependent Claim
33 words
The braking system as recited in claim 3 wherein the smallest interengaging tubular member is adapted to fixedly engage with the pressure plate and the largest interengaging tubular member is a spring follower.
Claim 8
Dependent Claim
34 words
The braking system as recited in claim 6 wherein there are three interengaging tubular members, the largest and smallest having spring gripping characteristics and the third such member comprising a substantially rigid tubular sleeve.
Claim 9
Dependent Claim
90 words
A telescopic brake piston assembly, comprising at least two interfitting pistons, a smaller piston being received in a larger piston, the larger piston being received in a sleeve housing, and wherein a cavity is created between the two pistons, the cavity containing at least one spring in operative engagement between the two pistons and at least one spring in operative engagement between the smaller piston and a control probe, the control probe serving as a valve means for regulating the flow of braking fluid into and out of the cavity.
Claim 10
Dependent Claim
90 words
A telescopic brake piston assembly, comprising at least two interfitting pistons, a smaller piston being received in a larger piston, the larger piston being received in a sleeve housing, and wherein a cavity is created between the two pistons, the cavity containing at least one spring in operative engagement between the two pistons and at least one spring in operative engagement between the smaller piston and a control probe, the control probe serving as a valve means for regulating the flow of braking fluid into and out of the cavity.
Claim 11
Dependent Claim
48 words
The telescopic brake piston assembly as recited in claim 8 wherein the smaller piston is adapted to be in operative engagement with the pressure plate of the brake disk stack and the larger piston is adapted to provide the braking force working area of the brake piston assembly.
Claim 12
Dependent Claim
42 words
The telescopic brake piston assembly as recited in claim 9 wherein the pistons and sleeve housing are provided with ring shoulders for restricting the movement of the smaller piston within the larger piston and of the larger piston within the sleeve housing.
Claim 13
Dependent Claim
47 words
The telescopic brake piston assembly as recited in claim 8 wherein the spring in operative engagement between the two pistons presents a force against the larger piston restraining movement thereof within the sleeve housing until the brake pressure within the brake piston assembly reaches a predetermined level.
Claim 14
Dependent Claim
62 words
The telescopic brake piston assembly as recited in claim 11 wherein the spring in operative engagement between the smaller piston and the control probe forces the probe to come into sealing engagement with a valve seat when the larger piston has moved a predetermined distance within the sleeve housing, such sealing causing the cavity and smaller piston to comprise a hydraulic column.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-12 | 1978-02-11 | 1978-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-12 | 1982-02-11 | 1982-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-12 | 1986-02-11 | 1986-08-13 | $7700.00 | Window Closed / Lapsed |