Patent US4376490A successfully refreshed from Google Patents.
US4376490A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Observing window device for liquid tanks
Assignee: Astemo Ltd
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Filing: 1980-10-31
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Granted: 1983-03-15
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Expires: 2000-10-31
Abstract
Abstract A flanged cup-shaped transparent pane member is fitted in a window opening formed in the tank wall and held liquid-tight against the latter by means of a pane retainer plate which is inserted along the wall inside into the pane member through slit means provided therein. The retainer plate fully inserted abuts against a shoulder formation on the wall inside and serves to hold the pane member against inadvertent rotation as well as against falling off the tank wall. That portion of the retainer plate which extends across the follow interior of the cup-shaped pane member serves as a light reflector means for enabling the user to observe the liquid level in the tank with ease and accuracy. A minimum level indicator is formed on the closed end wall of the pane member and a maximum level indicator on the retainer plate at its top for convenience in replenishing the liquid tank.
Inventors
- 👤 Yoshinobu Mizusaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:37
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/02; B; B60; B60T; B60T11/00; B60T11/10; B60T11/26; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2186
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
270 words
An observation window device for a liquid tank having a window opening formed in a side wall thereof, said window device comprising a generally cup-shaped transparent pane member including a side wall having an outer periphery with an abutment flange therearound, said side wall of the cup-shaped member being provided with slit means, said pane member having an open end extending into the interior of said liquid tank and including an integral lower limit level indicating portion for defining the lowest level of liquid in said liquid tank, pane retainer plate means engaged in said slit means and held in abutting engagement with an inside surface of said side wall of said liquid tank for resiliently urging said pane member inwardly of said liquid tank to place said abutment flange in fluid-tight contact with an outside surface of said side wall of said liquid tank and rotation-restraining means integrally formed with said pane retainer plate means for holding said pane member and said pane retainer plate means in place against rotation thereof relative to said liquid tank, said slit means including a pair of slits in opposition in said side wall of said cup-shaped pane member, said pane retainer plate means comprising a retainer plate including a pair of spaced, parallel grip legs respectively in fitting engagement in said slits and a bridge portion interconnecting said grip legs at the top thereof, said tank having a removable cover member, said bridge portion of said pane retainer plate being held in abutting engagement with said cover member so that said retainer plate is prevented from inadvertent disengagement from said pane member.
Claim 2
Dependent Claim
270 words
An observation window device for a liquid tank having a window opening formed in a side wall thereof, said window device comprising a generally cup-shaped transparent pane member including a side wall having an outer periphery with an abutment flange therearound, said side wall of the cup-shaped member being provided with slit means, said pane member having an open end extending into the interior of said liquid tank and including an integral lower limit level indicating portion for defining the lowest level of liquid in said liquid tank, pane retainer plate means engaged in said slit means and held in abutting engagement with an inside surface of said side wall of said liquid tank for resiliently urging said pane member inwardly of said liquid tank to place said abutment flange in fluid-tight contact with an outside surface of said side wall of said liquid tank and rotation-restraining means integrally formed with said pane retainer plate means for holding said pane member and said pane retainer plate means in place against rotation thereof relative to said liquid tank, said slit means including a pair of slits in opposition in said side wall of said cup-shaped pane member, said pane retainer plate means comprising a retainer plate including a pair of spaced, parallel grip legs respectively in fitting engagement in said slits and a bridge portion interconnecting said grip legs at the top thereof, said tank having a removable cover member, said bridge portion of said pane retainer plate being held in abutting engagement with said cover member so that said retainer plate is prevented from inadvertent disengagement from said pane member.
Claim 3
Dependent Claim
44 words
An observing window device as claimed in claim 1 in which said rotation-restraining means includes a first shoulder on the inside of said side wall of said liquid tank and a second shoulder on said pane retainer plate for engagement with said first shoulder.
Claim 4
Dependent Claim
44 words
An observing window device as claimed in claim 1 in which said rotation-restraining means includes a positioning shoulder on the inside of said side wall of said liquid tank and engageable with said two grip legs of said pane retainer plate at end thereof.
Claim 5
Dependent Claim
32 words
An observing window device as claimed in claim 1 in which said pane retainer plate includes level indicator means thereon for defining the upper limit of liquid level in said liquid tank.
Claim 6
Dependent Claim
51 words
An observing window device as claimed in claim 4 in which said level indicator means include a top surface of a horizontal bent portion of said pane retainer plate which is held in engagement with a horizontal shoulder formed on the inside surface of said side wall of said liquid tank.
Claim 7
Dependent Claim
52 words
An observing window device as claimed in claim 1 in which said grip legs of said pane retainer plate have ends with detent pawls protruding therefrom toward one another engaged with said cup-shaped transparent pane member so that said pane retainer plate is additionally held against inadvertent disengagement from said pane member.
Claim 8
Dependent Claim
39 words
An observing window device as claimed in claim 1 or 6 in which said grip legs of said pane retainer plate include lateral projections extending therefrom toward one another into the hollow interior of said cup-shaped transparent pane member.
Claim 9
Dependent Claim
28 words
An observing window device as claimed in claim 1 wherein said pane member includes a front wall, said lower limit level indicating portion being on said front wall.
Claim 10
Dependent Claim
36 words
An observing window device as claimed in claim 1 wherein said pane retainer plate is made of resilient material and is engaged under stress in said slit means and against said side wall of said tank.
Claim 11
Dependent Claim
42 words
An observing window device as claimed in claim 1 wherein said slit means, said pane retainer plate means and said rotation-restraining means are operatively oriented to position said lower limit level indicating portion in a horizontal attitude across said cup-shaped pane member.
References Cited (Backward Citations)
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Cited
US3248946A
Cited
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Cited
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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) | 1986-03-14 | 1986-09-13 | 1987-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-14 | 1990-09-13 | 1991-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-14 | 1994-09-13 | 1995-03-15 | $7700.00 | Window Closed / Lapsed |