US4057700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid level indicator
Assignee: Aisin Corp
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Filing: 1976-02-20
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Granted: 1977-11-08
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Expires: 1996-02-20
Abstract
Abstract A fluid level indicator for a reservoir of a brake tandem master cylinder includes a pair of partition walls extending vertically upwardly from the bottom of the reservoir and thereby dividing the reservoir into three chambers. One chamber is in fluid communication with one brake circuit, another chamber is in fluid communication with the other brake circuit, and the third or middle chamber defined between the two partition walls is utilized for sensing and indicating the fluid level of brake oil within the reservoir.
Inventors
- 👤 Katsushi Nakashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:02
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/30; G01F23/64; G01F23/72; G01F23/74; H; H01; H01H; H01H36/00; H01H36/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
205 words
A fluid level indicator for a reservoir of a brake tandem master cylinder, comprising: a pair of vertically extending partition walls provided within said reservoir and defining three chambers; float means disposed within the middle chamber defined by said partition walls, said float means being reciprocated in response to changes in the level of the brake fluid within said chamber; fluid level indicating circuit means for indicating the fluid level in response to the movement of said float means when the fluid level attains a predetermined level; said fluid level indicating circuit means including a reed switch positioned at said predetermined fluid level and actuated by means of a magnet incorporated within said float means; said pair of partition walls being provided with communication bores at a position just below said predetermined fluid level for communicating said three chambers with one another; wherein, said reservoir is provided with a first cap member detachably mounted upon the top of said reservoir and a second and third cap member detachably mounted to said reservoir adjacent to and located on opposite sides of said first cap member, respectively; said first cap member being provided with a dependent cylindrical stepped projection extending into said middle chamber of said reservoir;
Claim 2
Dependent Claim
205 words
A fluid level indicator for a reservoir of a brake tandem master cylinder, comprising: a pair of vertically extending partition walls provided within said reservoir and defining three chambers; float means disposed within the middle chamber defined by said partition walls, said float means being reciprocated in response to changes in the level of the brake fluid within said chamber; fluid level indicating circuit means for indicating the fluid level in response to the movement of said float means when the fluid level attains a predetermined level; said fluid level indicating circuit means including a reed switch positioned at said predetermined fluid level and actuated by means of a magnet incorporated within said float means; said pair of partition walls being provided with communication bores at a position just below said predetermined fluid level for communicating said three chambers with one another; wherein, said reservoir is provided with a first cap member detachably mounted upon the top of said reservoir and a second and third cap member detachably mounted to said reservoir adjacent to and located on opposite sides of said first cap member, respectively; said first cap member being provided with a dependent cylindrical stepped projection extending into said middle chamber of said reservoir;
Claim 3
Dependent Claim
89 words
said fluid level indicating circuit means being disposed within said projection of said first cap member; said float means is slidably engaged with said projection of said first cap member; said projection of said first cap member is provided with two shoulder portions between which said float means is movable; and, said partition walls are formed integrally with said reservoir and extending vertically upwardly from the bottom of said reservoir and displaced from the top of said reservoir so as to form an opening which connects said three chambers.
Claim 4
Dependent Claim
89 words
said fluid level indicating circuit means being disposed within said projection of said first cap member; said float means is slidably engaged with said projection of said first cap member; said projection of said first cap member is provided with two shoulder portions between which said float means is movable; and, said partition walls are formed integrally with said reservoir and extending vertically upwardly from the bottom of said reservoir and displaced from the top of said reservoir so as to form an opening which connects said three chambers.
Claim 5
Dependent Claim
38 words
A fluid level indicator as set forth in claim 1, wherein: said remaining two chambers of said reservoir are respectively in fluid communication with the respective fluid brake circuits of said vehicle for independently supplying brake pressure thereto.
References Cited (Backward Citations)
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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) | 1980-11-07 | 1981-05-09 | 1981-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-07 | 1985-05-09 | 1985-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-07 | 1989-05-09 | 1989-11-08 | $7700.00 | Window Closed / Lapsed |