Patent US3654689A successfully refreshed from Google Patents.
US3654689A
Expired / Lapsed
US
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Method and apparatus of assembling and disassembling hydraulic disc brake calipers
Assignee: Standard Motor Products Inc
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Filing: 1970-06-03
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Granted: 1972-04-11
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Expires: 1990-06-03
Abstract
Abstract A method and apparatus for releasing frozen pistons from a disc brake caliper assembly by removing said assembly from a vehicle, removing the brake pads therefrom and placing it on a work table. The work table has a self-contained hydraulic system and a vacuum line is also provided. A spacer block of predetermined thickness is placed between the opposed pistons, and a pressure line connected to the caliper assembly. A hand pump is used to increase system pressure until all the hydraulic pistons, including any frozen pistons, move out of their bores to engage the spacer block. The hydraulic pressure is then released by a manual valve, and the hydraulic line disconnected so that the spacer block can be removed and the defective pistons removed from the caliper assembly. The defective piston, or pistons, are replaced by operable ones, and the vacuum line used to drawn them into their bores, after which the caliper assembly is prefilled with hydraulic fluid and pressure tested prior to reinstallation in the vehicle.
Inventors
- 👤 Maurice L Schwarz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:51
CPC Classifications
F; F16; F16D; F16D65/00; F16D65/0043; B; B25; B25B; B25B27/00; B25B27/02; B25B27/026; F16D55/00; F16D55/02; F16D55/22; F16D55/228; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49249; Y10T29/4925; Y10T29/49718; Y10T29/49721; Y10T29/4973; Y10T29/53; Y10T29/53796; Y10T29/5383
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
128 words
Apparatus for removing frozen pistons from an automotive type disc brake caliper assembly which includes at least one piston in a bore, said apparatus comprising a work table, a source of hydraulic fluid, a hydraulic manifold, manually operated pump means for pressurizing said manifold, a pressure line for pressurizing the caliper assembly from said manifold, a pressure release valve in said manifold, and a spacer block for use with said caliper assembly to provide a reaction member against which a piston can act, said spacer block having a thickness such that the piston must move through a displacement considerably greater than required when the caliper assembly is in use on a vehicle but less than the displacement required to cause a loss in pressure in the piston bore.
Claim 2
Dependent Claim
128 words
Apparatus for removing frozen pistons from an automotive type disc brake caliper assembly which includes at least one piston in a bore, said apparatus comprising a work table, a source of hydraulic fluid, a hydraulic manifold, manually operated pump means for pressurizing said manifold, a pressure line for pressurizing the caliper assembly from said manifold, a pressure release valve in said manifold, and a spacer block for use with said caliper assembly to provide a reaction member against which a piston can act, said spacer block having a thickness such that the piston must move through a displacement considerably greater than required when the caliper assembly is in use on a vehicle but less than the displacement required to cause a loss in pressure in the piston bore.
Claim 3
Dependent Claim
54 words
Apparatus according to claim 1 further characterized by a vacuum source of air pressure associated with said work table, a vacuum line connectible with said caliper assembly for evacuating trapped air therein, and for use in reassembling the pistons in their associated bores so that the pistons are properly aligned therein during said reassembly.
Claim 4
Independent Claim
150 words
A method for releasing frozen pistons from an automotive type disc brake caliper assembly which includes at least one piston mounted in a bore for engaging an associated brake pad, said method comprising placing the caliper assembly on a work table which includes a self-contained hydraulic system, removing the brake pads, placing a spacer block in the space formerly occupied by said brake pads, connecting the caliper assembly to said hydraulic system, applying hydraulic pressure to the hydraulic system by a manual pump to cause the piston to travel through a displacement considerably greater than that possible when the caliper assembly is installed in the vehicle, said piston travel being limited only by engagement with the spacer block, which block is thin enough to achieve said displacement but thick enough so as to preclude loss of hydraulic system pressure due to fluid leakage between the piston and the piston bore.
Claim 5
Independent Claim
150 words
A method for releasing frozen pistons from an automotive type disc brake caliper assembly which includes at least one piston mounted in a bore for engaging an associated brake pad, said method comprising placing the caliper assembly on a work table which includes a self-contained hydraulic system, removing the brake pads, placing a spacer block in the space formerly occupied by said brake pads, connecting the caliper assembly to said hydraulic system, applying hydraulic pressure to the hydraulic system by a manual pump to cause the piston to travel through a displacement considerably greater than that possible when the caliper assembly is installed in the vehicle, said piston travel being limited only by engagement with the spacer block, which block is thin enough to achieve said displacement but thick enough so as to preclude loss of hydraulic system pressure due to fluid leakage between the piston and the piston bore.
Claim 6
Dependent Claim
99 words
The method according to claim 3 further characterized by the successive steps of depressurizing the hydraulic system following the procedure outlined in claim 3, removing the now unfrozen piston and the spacer block, removing the pressure line and allowing the fluid in the caliper assembly to drain onto the work table, connecting the caliper to a vacuum pressure source, and placing a piston together with its associated seals and other component parts adjacent each of the bores in the caliper assembly so that each piston is drawn into its associated bore by suction supplied by said vacuum pressure source.
Claim 7
Dependent Claim
124 words
The method according to claim 4 further characterized by the steps of disconnecting the vacuum line following the completion of the procedure outlined in claim 4, connecting the caliper assembly to said hydraulic system, placing said spacer block in the space defined above and adding shimming means to said spacer block to increase the effective thickness thereof and reduce the possible displacement of the piston, applying hydraulic pressure to the hydraulic system to cause the piston to travel through a displacement substantially equal to that possible when the caliper assembly is installed in the vehicle, continuing to apply pressure by said hand pump to a predetermined test pressure, inspecting the caliper assembly for leaks, and check the pressure gage for loss of system pressure.
References Cited (Backward Citations)
US3058207A
Cited
US1883662A
Cited
US2033906A
Cited
US2234819A
Cited
US2439692A
Cited
US2557619A
Cited
US3137060A
Cited
US3413709A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |