US4173750A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Incandescent lamp monitoring device
Assignee: Individual
•
Filing: 1977-12-27
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Granted: 1979-11-06
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Expires: 1997-12-27
Abstract
Abstract A monitoring device for monitoring incandescent lamps, especially in motor vehicles, is provided. A measuring resistor is connected in series with an incandescent lamp to be monitored. Means for monitoring the voltage drop at the measuring resistor are provided. The monitoring means comprises an operational amplifier to one input of which the connection between the measuring resistor and the incandescent lamp is connected and to the other input of which a voltage divider is connected which is mounted in parallel with the measuring resistor and the incandescent lamp. The voltage divider is formed of ohmic resistors, and the output of the operational amplifier controls an indicator means for generating an indication signal upon missing or excessively low voltage drop at the measuring resistor.
Inventors
- 👤 Jutta Riba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 01:18
CPC Classifications
B; B60; B60Q; B60Q11/00
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
179 words
In a device for monitoring lamps, in particular lamps of motor vehicles, comprising a measuring resistor connected in series with a lamp to be monitored and means for monitoring the potential drop at the measuring resistor, said monitoring means comprising an operational amplifier and said monitoring device comprising indicator means controlled by said operational amplifier for providing an indication in case of absence of or excessively low potential drop at said resistor, the improvement wherein said operational amplifier comprises a first input and a second input, said first input connected with the junction between said measuring resistor and said lamp to be monitored, and wherein said monitoring means comprises a voltage divider including a first ohmic resistor connected in series with a second ohmic resistor, said series connection of said first ohmic resistor and said second ohmic resistor being connected in parallel with the serial connection of said measuring resistor and said lamp to be monitored, and said second input of said operational amplifier being connected with the junction between said first ohmic resistor and said second ohmic resistor.
Claim 2
Dependent Claim
179 words
In a device for monitoring lamps, in particular lamps of motor vehicles, comprising a measuring resistor connected in series with a lamp to be monitored and means for monitoring the potential drop at the measuring resistor, said monitoring means comprising an operational amplifier and said monitoring device comprising indicator means controlled by said operational amplifier for providing an indication in case of absence of or excessively low potential drop at said resistor, the improvement wherein said operational amplifier comprises a first input and a second input, said first input connected with the junction between said measuring resistor and said lamp to be monitored, and wherein said monitoring means comprises a voltage divider including a first ohmic resistor connected in series with a second ohmic resistor, said series connection of said first ohmic resistor and said second ohmic resistor being connected in parallel with the serial connection of said measuring resistor and said lamp to be monitored, and said second input of said operational amplifier being connected with the junction between said first ohmic resistor and said second ohmic resistor.
Claim 3
Dependent Claim
37 words
Monitoring device of claim 1, wherein a malfunction simulating arrangement connected between one of said inputs of said operational amplifier and one terminal of the supply voltage is provided for testing the operativeness of said monitoring device.
Claim 4
Dependent Claim
45 words
Monitoring device of claim 2, wherein said malfunction simulating arrangement comprises a diode, a switch connected in series with said diode, said serially connected switch and diode being connected between said one terminal of the supply voltage and said one input of said operational amplifier.
Claim 5
Dependent Claim
27 words
Monitoring device of claim 1, wherein an electronic switch controlled by the output of said operational amplifier is provided between said operational amplifier and said indicator means.
Claim 6
Dependent Claim
24 words
Monitoring device of claim 4, wherein said electronic switch is controllable by switching means which may be manually operated, for testing the supply voltage.
Claim 7
Dependent Claim
29 words
Monitoring device of claim 1, wherein a plurality of said monitoring means are combined in a constructional unit for monitoring a plurality of incandescent lamps with separate current circuits.
Claim 8
Dependent Claim
46 words
Monitoring device of claim 6, wherein each of said monitoring means includes a failure simulating arrangement for testing the operativeness of said monitoring device and having one control input, and wherein the control inputs of several failure simulating arrangements are connected with a common operating switch.
Claim 9
Dependent Claim
41 words
Monitoring device of claim 6, wherein each monitoring means has one output for controlling the indicator means and said control outputs of said monitoring means are respectively connected through a diode to a common control output for a common indicator means.
Claim 10
Dependent Claim
65 words
Monitoring device of claim 6, wherein for each of said monitoring units said constructional unit has one terminal for a light switch, one terminal for a lamp circuit to be monitored, one control output for an indicator means as well as one control terminal common to the monitoring units and intended for said failure simulating arrangements, and a control output for a common indicator means.
Claim 11
Dependent Claim
48 words
Monitoring device of claim 3, wherein said voltage divider includes a series resistor, said diode connects between said series resistor and a resistor of said voltage divider, and wherein a further diode for forming a second control input is connected directly with one input of said operational amplifier.
Claim 12
Dependent Claim
82 words
Monitoring device of claim 3, comprising in addition a switching means connected between said one terminal of the supply voltage and the output of said operational amplifier, a common two-step operating means connected to said switch of said malfunction simulating means and also connected to said switching means, said switch being closed by said operating means at the first step for malfunction testing and said switching means being closed by said operating means at the second step for testing the supply voltage.
Claim 13
Dependent Claim
22 words
Monitoring device of claim 11, wherein said switching means comprises a second switch and a resistor serially connected to said second switch.
Claim 14
Dependent Claim
30 words
Monitoring device of claim 1, wherein a fuse is interconnected between the junction of said measuring resistor and one of said inputs of said operational amplifier and said incandescent lamp.
Claim 15
Dependent Claim
83 words
The improvement of claim 1, wherein said motor vehicle comprises a power supply voltage, a lamp operating switch serially connected with said lamp to be monitored, said serial connection of said lamp operating switch and lamp being connected between said measuring resistor and one terminal of said supply voltage, and said monitoring device is connected between the positive and the negative terminals of said power supply voltage to be thereby energized and operative independently of the switching state of said lamp operating switch.
Claim 16
Dependent Claim
64 words
The improvement of claim 1, wherein said monitoring means comprises switch means operated by an ignition switch of said motor vehicle, said switch means, in the switched-off position of said ignition switch, connecting one of said inputs of said operational amplifier with a potential of such level as to bias said operational amplifier to its state driving said indicator means to generate said indication.
Claim 17
Dependent Claim
35 words
The improvement of claim 1, wherein at least one diode is connected in parallel with said measuring resistor, said diode limiting the voltage drop at said measuring resistor in the forward direction of said diode.
Claim 18
Dependent Claim
18 words
The improvement of claim 16, wherein a plurality of diodes is connected in parallel with said measuring resistor.
Claim 19
Dependent Claim
37 words
The improvement of claim 16, wherein said diode has a current conducting threshold voltage in its forward direction which is in excess of the voltage drop generated at said measuring resistor without the presence of any malfunction.
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) | 1982-11-05 | 1983-05-07 | 1983-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-05 | 1987-05-07 | 1987-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-05 | 1991-05-07 | 1991-11-06 | $7700.00 | Window Closed / Lapsed |