US3919689A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle speed indicator system
Assignee: Caterpillar Industrial Inc
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Filing: 1974-06-03
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Granted: 1975-11-11
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Expires: 1994-06-03
Abstract
Abstract A series of differently colored lights are attached to a fork lift truck or the like to indicate the speed of the vehicle to bystanders as well as to the operator. A magnetic sensing device is disposed adjacent a toothed gear in the vehicle drive train to produce electrical pulses at a rate dependent on speed and a compact solid state circuit analyzes pulse rate to actuate a different colored light at each of a series of progressively higher speed ranges. Portions of the route along which the vehicle travels may be marked with matching colors indicative of maximum safe speed so that it is immediately apparent if a vehicle is being operated in an unsafe manner.
Inventors
- 👤 James E Despain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:00
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/4802; G01P3/4805; B; B60; B60Q; B60Q1/00; B60Q1/26; B60Q1/50; B60Q1/54; B66; B66F; B66F17/00; B66F17/003; G01P1/00; G01P1/07; G01P1/08; G01P1/10; G01P1/103
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
337 words
In combination with an industrial lift truck vehicle which is to be driven along a predetermined route wherein different maximum safe speeds exist at different portions of said route, a speed-indicating system for said veHicle comprising: a plurality of electrical lamps each producing a different colored light; means for attaching said plurality of lamps on said vehicle in position to be observable from viewpoints outside said vehicle; means for magnetically sensing rotation of a rotary element coupled to the drive system of said vehicle and for producing a DC signal having a magnitude which is a function of the rotary speed of said element, werein said rotary element of said vehicle is a gear having teeth thereon and which is formed of ferromagnetic material and wherein said means for magnetically sensing rotation of said element comprises a magnet having an end situated adjacent the path of travel of said teeth of said element and having an electrical coil disposed in the magnetic field of said magnet to produce electrical pulses having a repetition rate which is a function of the speed of said element, said coil being coupled to means for averaging said electrical pulses to produce said DC signal, circuit means for detecting when said DC signal reaches each of a plurality of different magnitude ranges and for energizing different colored ones of said lamps when said DC signal is within different ones of said magnitude ranges each of said DC signal magnitude ranges having an end point corresponding to a separate one of said maximum safe speeds to light a different one of said lamps as speed rises above each of said maximum safe speeds, and indicator means disposed at least at intervals along said predetermined route of travel and being colored to indicate the maximum safe speed range of the adjacent portion of said route, the color of said indicator means corresponding to the color of the one of said lamps which is lighted as said lift truck reaches said maximum safe speed range.
Claim 2
Dependent Claim
337 words
In combination with an industrial lift truck vehicle which is to be driven along a predetermined route wherein different maximum safe speeds exist at different portions of said route, a speed-indicating system for said veHicle comprising: a plurality of electrical lamps each producing a different colored light; means for attaching said plurality of lamps on said vehicle in position to be observable from viewpoints outside said vehicle; means for magnetically sensing rotation of a rotary element coupled to the drive system of said vehicle and for producing a DC signal having a magnitude which is a function of the rotary speed of said element, werein said rotary element of said vehicle is a gear having teeth thereon and which is formed of ferromagnetic material and wherein said means for magnetically sensing rotation of said element comprises a magnet having an end situated adjacent the path of travel of said teeth of said element and having an electrical coil disposed in the magnetic field of said magnet to produce electrical pulses having a repetition rate which is a function of the speed of said element, said coil being coupled to means for averaging said electrical pulses to produce said DC signal, circuit means for detecting when said DC signal reaches each of a plurality of different magnitude ranges and for energizing different colored ones of said lamps when said DC signal is within different ones of said magnitude ranges each of said DC signal magnitude ranges having an end point corresponding to a separate one of said maximum safe speeds to light a different one of said lamps as speed rises above each of said maximum safe speeds, and indicator means disposed at least at intervals along said predetermined route of travel and being colored to indicate the maximum safe speed range of the adjacent portion of said route, the color of said indicator means corresponding to the color of the one of said lamps which is lighted as said lift truck reaches said maximum safe speed range.
Claim 3
Dependent Claim
68 words
The combination defined in claim 1 wherein said industrial lift truck vehicle has an overhead guard structure above the operator''s compartment including upwardly extending overhead guard supporting posts at each side of said vehicle and forward fom said operator''s compartment, and wherein said means for attaching said plurality of lamps on said vehicle secures said plurality of lamps to at least one of said upwardly extending posts thereof.
Claim 4
Dependent Claim
34 words
A speed-indicating system as defined in claim 2 wherein said lamps are mounted on said vehicle to be visible from the operator''s compartment thereof as well as being visible from viewpoints outside said vehicle.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |