Fuse blowing detector

• US 4,281,322 A
• Filed: 09/12/1979
• Issued: 07/28/1981
• Est. Priority Date: 10/04/1978
• Status: Expired due to Term

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Nasu, Tetsuji, Nagayama, Mitsuyoshi
• Primary Examiner(s): Brigance, Gerald L.
• Application Number:
  US06/075,181
• Time in Patent Office: 685 Days
• Field of Search: 340/639, 340/638, 339/150 F, 339/252 F, 339/253 F, 339/262 F, 361/341, 361/349, 337/206, 337/212, 337/241, 337/242, 337/196, 200/61.7
• US Class Current: 340/638
• CPC Class Codes: H01H 85/32 Indicating lamp structurally associated with the protective device

Abstract

A device for detecting whether any of a plurality of fuses has blown out. The fuses are connected between a first terminal of an electrical source and a number of loads, the loads also being connected to the other terminal of the source. The device comprises one light emitting element for each fuse. One end of the light emitting element is connected to a junction between the fuse and its load. The other ends of the light emitting elements are all connected together to one terminal of a switch, having another terminal connected to the other terminal of the electrical source. When the switch is closed, the light emitting element corresponding to any fuse which has blown out is not lit.

Claims

1. In an electrical circuit wherein a first terminal of an electrical source is connected to first terminals of a plurality of fuses, and the second terminal of the fuses are connected to the first terminals of the same number of loads, the other terminals of the loads being connected to the other terminal of the electrical source, whereby the loads are supplied with electrical power via their respective fuses,

a device for detecting the blowing of any one of the fuses, comprising:

(a) for each fuse, a light emitting element, one terminal of which is connected to the second terminal of the fuse,

(b) a switch, one terminal of which is connected to all the other terminals of all the light emitting elements, and the other terminal of which is connected to the said other terminal of the electrical source, and

(c) an electrically insulating housing for each fuse, each fuse being mounted in its housing between two spaced electrically conductive strips, one of the strips being connected, via the light emitting element which corresponds to the fuse, to a third electrically conductive strip mounted within the housing, the light emitting element being received in a groove on said housing, the third strips all being connected together to the switch, the one strips all being each connected to the load corresponding to this fuse, the remaining strips being connected to the electrical source.

2. A device according to claim 1, wherein the strips are formed with shoulders which act as stops and abut on the housings.

4. A device according to claim 1 or 2 or 3, wherein the light emitting elements are light emitting diodes, and the polarities of the source and the diodes are such that, if the switch is closed, and a fuse is intact, its corresponding diode may light.

5. A device according to claim 1 or 2 or 3, wherein the light emitting elements are electric lamps.

6. A device according to claim 1 or 2 or 3, further including a block in which the fuses and light emitting elements are arranged in an easy-to-see way in one-to-one correspondence with one another.

3. A fusing device for connecting an electrical source to plural loads, comprising:

(a) a fuse for each load;

(b) a light emitting element for each fuse;

(c) a separate, electrically insulating housing for each of said fuses, said housing having a groove for receiving one of the light emitting elements;

(d) each housing receiving a pair of spaced first and second electrically conductive strips for each of said fuses, one of said fuses being mounted in bridging relation between said first and second strips of each housing whereby current flows between the first and second strips via the fuse associated with the housing, said first strip being adapted to be connected to said electrical source, said second strip being adapted to be connected to a corresponding load;

(e) each housing receiving a third electrically conductive strip spaced from the first and second electrically conductive strips of the housing, said third strip being electrically connected through the light emitting element of the housing to the second strip of the housing; and

(f) a switch having one terminal connected to all said third strips and another terminal adapted to be connected to said electrical source.

7. A fusing device for connecting an electrical source and a plurality of loads, comprising:

(a) a fuse for each load, each fuse connecting a corresponding load and one terminal of the electrical source;

(b) a light emitting element for each fuse, each light emitting element having first and second terminals, said terminals of each element being connected to a junction between the load and fuse corresponding to the light emitting element;

(c) a single pole, single throw switch having one terminal connected to the second terminal of all of said light emitting elements and another terminal of said switch being selectively connected to a second terminal of said electrical source; and

(d) a box-like block having an outer surface on which said fuses and light emitting elements are arranged in visible one-to-one correspondence with one another.

8. The device of claim 7 wherein the terminals of said switch, electrical source and light emitting elements are connected in circuit with said fuses so that closure of the switch contacts results in current flow through operable fuses and corresponding light emitting elements, whereby the elements corresponding to the operable fuses are lit in response to the switch closure.

9. A device according to claim 7, wherein the switch is mounted in the block.

10. A device according to claim 9, wherein the switch is a switch which is normally on, and further comprising a cover for the block, which when fitted to the block presses on the switch so that it is held off;

so that when the cover is removed the switch is automatically connected.

11. A device according to claim 10, wherein the block is provided in the instrument panel of an automobile, and the cover is an instrument panel cover.

12. A circuit for independently indicating the status of fuses of branch circuits powered by a single source in response to closure of a single pole, single throw switch, each of the branch circuits including a fuse and load electrically connected across opposite terminals of the source and an intermediate terminal between the load and fuse, said circuit comprising the single pole, single throw switch, said switch having one terminal connected to the one terminal of the source connected to the load, and a separate current responsive light source for each branch, one terminal of each light source being connected to the intermediate terminal of the branch associated with the light source, one terminal of each light source being connected to a second terminal of the switch, whereby closure of the switch contacts results in current flow through each of the light sources connected to branches having operative fuses causing the light sources connected to the branches having operative fuses to be lit, a common block in which all of said light sources are positioned to enable the sources to be viewed while the switch is closed.

13. The circuit of claim 12 further including a cover for said block, said cover including a face for engaging an actuator for the switch contacts to maintain the contacts in an open circuited condition and for obscuring the light sources while the cover is on the block, the contacts being closed when the cover is off the block and the light sources are not obscured by the cover.

14. The circuit of claim 12 wherein each branch is contained in an electrical insulating housing adapted to be mounted in the block, each of said housings having:

a top with first, second and third openings, first, second and third electrically conducting strips having first ends respectively secured in said first, second and third openings and extending from the openings in generally the same direction, the fuse bridging the first and second strips, the light source being mounted in the housing between and electrically connected to said second and third strips, the other ends of said first, second and third strips being respectively electrically connected to one terminal of the source, one terminal of the load and one terminal of the switch.

15. The circuit of claim 14 wherein the single source is a DC power supply and the light source is a light emitting diode polarized to pass current from the DC power supply in response to the switch contacts being closed and the fuse being operative, each housing being easily removed and inserted in the block and asymmetrically arranged to assure proper polarization of the diode in the circuit.

16. A circuit for independently indicating the status of fuses of branch circuits powered by a single source in response to closure of a single pole, single throw switch, each of the branch circuits including a fuse and load electrically connected across opposite terminals of the source and an intermediate terminal between the load and fuse, said indicator circuit comprising the single pole, single throw switch, said switch having one terminal connected to one terminal of the source and a separate current responsive light source for each branch, one terminal of each light source being connected to the intermediate terminal of the branch associated with the light source, one terminal of each light source being connected to a second terminal of the switch, whereby closure of the switch contacts results in current flow through the light sources to indicate which of the fuses are operative, a common block in which all of said light sources are positioned, said block having an outer surface on which said fuses and light sources are arranged in visible one-to-one correspondence with one another.

17. The circuit of claim 16 wherein each branch is contained in an electrical insulating housing adapted to be mounted in the block, each of said housings having:

a top with first, second and third openings, first, second and third electrically conducting strips having first ends respectively secured in said first, second and third openings and extending from the openings in generally the same direction, the fuse bridging the first and second strips, the light source being mounted in the housing between and electrically connected to said second and third strips, the other ends of said first, second and third strips being respectively electrically connected to one terminal of the source, one terminal of the load and one terminal of the switch.

18. The circuit of claim 17 wherein the single source is a DC power supply and the light source is a light emitting diode polarized to pass current from the DC power supply in response to the switch contacts being closed and the fuse being operative, each housing being easily removed and inserted in the block and asymmetrically arranged to assure proper polarization of the diode in the circuit.