US3825808A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal-seeking, power-driven mast for use in laser beam controls and surveying systems
Assignee: Trimble Inc
•
Filing: 1973-05-10
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Granted: 1974-07-23
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Expires: 1993-05-10
Abstract
Abstract This invention relates to the construction of a power-driven extensible mast for mounting a photocell unit which is utilized to detect a laser beam which is periodically swept over a working area at a known elevation. Suitable circuits are provided between the photocell unit carried by the extensible mast and a motor unit which effects the raising and lowering of the mast to automatically maintain the mast at a height corresponding to exact vertical alignment with the photocell unit with the laser beam. Another feature of the invention is the provision of automatic limit switch means which function to reverse the direction of the driving motor when the mast reaches either the top or bottom extremity of its vertical movement.
Inventors
- 👤 T Teach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:29
CPC Classifications
E; E02; E02F; E02F9/00; E02F9/20; E02F9/2025; E02F9/2045; G; G01; G01C; G01C15/00; G01C15/002; G01C15/004; G01C15/006; Y; Y10; Y10S; Y10S37/00; Y10S37/906
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
200 words
A vertically adjustable mast for mountinG a laser beam detecting unit comprising: 1. a mounting base having a horizontal wall and a depending peripheral flange defining a power transmission chamber; 2. an upstanding cylindrical wall on said base; 3. a tubular housing anchored in said cylindrical wall; 4. a tubular mast slidably mounted in said housing, said mast having an internally threaded nut member rigidly mounted to the lower portion of said mast and concentrically disposed relative to the axis of said tubular mast; 5. an elongated screw engaging the threads of said nut member and having a lower shaft portion journalled in said horizontal wall and projecting into said power transmission chamber; 6. a reversible motor mounted on said horizontal wall and having a vertical driveshaft projecting downwardly into said transmission chamber; 7. speed reduction means interconnecting said motor shaft and said shaft portion of said screw, whereby said motor effects raising or lowering movements of said mast relative to said housing; and 8. limit switch means mounted on the end of said shaft portion of said elongated screw and operably connected to said reversible motor to de-energize same whenever said mast approaches its top or bottom limiting position.
Claim 2
Dependent Claim
200 words
A vertically adjustable mast for mountinG a laser beam detecting unit comprising: 1. a mounting base having a horizontal wall and a depending peripheral flange defining a power transmission chamber; 2. an upstanding cylindrical wall on said base; 3. a tubular housing anchored in said cylindrical wall; 4. a tubular mast slidably mounted in said housing, said mast having an internally threaded nut member rigidly mounted to the lower portion of said mast and concentrically disposed relative to the axis of said tubular mast; 5. an elongated screw engaging the threads of said nut member and having a lower shaft portion journalled in said horizontal wall and projecting into said power transmission chamber; 6. a reversible motor mounted on said horizontal wall and having a vertical driveshaft projecting downwardly into said transmission chamber; 7. speed reduction means interconnecting said motor shaft and said shaft portion of said screw, whereby said motor effects raising or lowering movements of said mast relative to said housing; and 8. limit switch means mounted on the end of said shaft portion of said elongated screw and operably connected to said reversible motor to de-energize same whenever said mast approaches its top or bottom limiting position.
Claim 3
Dependent Claim
7 words
an upstanding cylindrical wall on said base;
Claim 4
Dependent Claim
7 words
an upstanding cylindrical wall on said base;
Claim 5
Dependent Claim
47 words
The combination defined in claim 1, plus an indicating shaft journalled in said base, and gear means for driving said indicating shaft in fixed ratio relationship with said elongated screw, whereby the rotation of said indicating shaft is a linear function of the height of said mast.
Claim 6
Dependent Claim
96 words
The combination defined in claim 1, wherein said limit switch means comprises a horizontally disposed rod journalled in said transmission chamber''s reduction gearing, means interconnecting said lower end of said elongated screw and said rod, said rod having its opposed ends threaded, a pair of internally threaded blocks mounted on said threaded ends of said rod, whereby rotation of said rod effects axial movements of said blocks, and a pair of limit switches respectively actuated by said blocks when said blocks respectively move to positions respectively corresponding to maximum extension or maximum contraction of said mast.
Claim 7
Dependent Claim
8 words
a tubular housing anchored in said cylindrical wall;
Claim 8
Dependent Claim
8 words
a tubular housing anchored in said cylindrical wall;
Claim 9
Dependent Claim
36 words
a tubular mast slidably mounted in said housing, said mast having an internally threaded nut member rigidly mounted to the lower portion of said mast and concentrically disposed relative to the axis of said tubular mast;
Claim 10
Dependent Claim
36 words
a tubular mast slidably mounted in said housing, said mast having an internally threaded nut member rigidly mounted to the lower portion of said mast and concentrically disposed relative to the axis of said tubular mast;
Claim 11
Dependent Claim
28 words
an elongated screw engaging the threads of said nut member and having a lower shaft portion journalled in said horizontal wall and projecting into said power transmission chamber;
Claim 12
Dependent Claim
28 words
an elongated screw engaging the threads of said nut member and having a lower shaft portion journalled in said horizontal wall and projecting into said power transmission chamber;
Claim 13
Dependent Claim
19 words
a reversible motor mounted on said horizontal wall and having a vertical driveshaft projecting downwardly into said transmission chamber;
Claim 14
Dependent Claim
19 words
a reversible motor mounted on said horizontal wall and having a vertical driveshaft projecting downwardly into said transmission chamber;
Claim 15
Dependent Claim
30 words
speed reduction means interconnecting said motor shaft and said shaft portion of said screw, whereby said motor effects raising or lowering movements of said mast relative to said housing; and
Claim 16
Dependent Claim
30 words
speed reduction means interconnecting said motor shaft and said shaft portion of said screw, whereby said motor effects raising or lowering movements of said mast relative to said housing; and
Claim 17
Dependent Claim
35 words
limit switch means mounted on the end of said shaft portion of said elongated screw and operably connected to said reversible motor to de-energize same whenever said mast approaches its top or bottom limiting position.
Claim 18
Dependent Claim
35 words
limit switch means mounted on the end of said shaft portion of said elongated screw and operably connected to said reversible motor to de-energize same whenever said mast approaches its top or bottom limiting position.
References Cited (Backward Citations)
US3002598A
Cited
US3341760A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |