US3813626A

US3813626A - Fuse retainer and extractor

Info

Publication number: US3813626A
Application number: US00315323A
Authority: US
Inventors: H Cetola; T Crosby
Original assignee: Robertshaw Controls Co
Current assignee: Robertshaw Controls Co
Priority date: 1972-12-15
Filing date: 1972-12-15
Publication date: 1974-05-28
Anticipated expiration: 1991-05-28

Abstract

A fuse holder constructed from a dielectric material which is also elastic or partly elastic, such as plastic, formed to provide a cylinder split longitudinally and chamfered at either end to receive a cartridge fuse, such cylinder having attached thereto a handle to facilitate grasping of the fuse holder. At the distal ends, the handle extends to form insulating chambers partly surrounding the respective connector end caps of the fuse and opening along one lateral surface thereof to receive the corresponding spring clips of a fuse clip. The distally opposite surfaces of the respective housings are pierced to form openings concentric with the axis of the cylinder, said openings being sized to pass the fuse into the interior cavity of the cylinder. In another embodiment, the handle is formed to provide a second fuse holder substantially shaped in a similar manner as the first fuse holder, for holding a spare fuse for replacement.

Description

United States Patent 1191 'Cetola et a1.

111 3,813,626 May 28, 1974 FUSE RETA INER AND EXTRACTOR Inventors: Henry A. Cetola, Yorba Linda;

Timothy J. Crosby, Anaheim, both of Calif.

Robertshaw Controls Company, Richmond, Va.

Filed: Dec. 15, 1972 Appl. No.: 315,323

Assignee:

US. Cl. 337/245, 174/138 F, 174/138 G, 337/186, 337/213, 337/215, 337/264 Int. Cl. H0lh 85/14 Field of Search 337/186, 194, 215, 245, 337/202, 209, 138,213,264; 174/138 G,

References Cited I UNITED STATES PATENTS FOREIGN PATENTS OR APPLICATIONS;

6/1941 Fenske et al....

18,276 8/1914 Great Britain 337/245 1,109,610 9/1955 France ..337/264 3/1955 Australia....; 337/245 11/1935 Baker ..337/245x 3/1966 Melia 174/138 G Primary Examiner-Bernard A. Gilheany Assistant Examiner-Fred E. Bell A Attorney, Agent, or FirmFulwider, Patton, Rieber, Lee & Utecht [57] ABSTRACT A fuse holder constructed from a dielectric material which is also elastic or partly elastic, such as plastic, formed to provide a cylinder split longitudinally and chamfered at either end to receive a cartridge fuse, such cylinder having attached thereto a handle to facilitate grasping of the fuse holder. At the distal ends, the handle extends to form insulating chambers partly surrounding the respective connector end caps of the fuse and opening along one lateral surface thereof to receive the corresponding spring clips of a fuse clip. The distally opposite surfaces of the respective housings are pierced to form openings concentric with the axis of the cylinder, said openings being sized topass the fuse into the interior cavity of the cylinder. In another embodiment, the handle is'formed to provide a second fuse holder substantially shaped in a similar manner as the first fuse holder, for holding a spare fuse for replacement.

I 9 Claims, 5 Drawing Figures PATENTEDIM 2a 1914 Pam FIG..2

l FUSE RETAINER AND EXTRACTOR I BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to fuse holders, and more particularly to fuse holders adapted to receive fuses of thecartridge type for a manual installation and extraction thereof in corresponding fuse clips.

2. Description of the Prior Art In the electrical art it has been the common practice to provide fuse protection to various elements of a circuit in order to insure that any current overload in the circuit will first destroy the fuse, thereby opening the circuit and protecting other more critical or expensive items on the line. Very often such critical components are designed to operate at different power levels, thus cal circuit. Furthermore, very often such circuits include a plurality of circuit elements drawing in parallel power from a common power source and separate fuse protection of each circuit element is required in order to limit the element to a safe current load. Thus, it has been the general practice in the prior art to provide a plurality of fuses in any-one circuit, conveniently located in one centralized location, for protection and diagnosis. Physical space considerations, particularly in circuits having a large number of circuit elements and therefore a large number of fuses, often dictates small fuse dimensions, and for such applications, fuses of the cartridge type have had most prevailing application. Such cartridge fuses generally comprise an insulator tube closed at both ends by conductive end caps, having disposed therebetween a fuse bus connecting the end caps. The end caps engage respective fuse clips connected to the ends of respective leads. In this manner, the fuse closes the circuit betweenthe respective end clips and upon removal thereof at least one of the end clips is usually energized, presenting a hazard of shock and injury to the manual installer. Thus, there have been many prior art devices developed in the past which are specifically adapted to provide a means for insulated manual grasping of the cartridge fuse without unnecessarily exposing the installer to shock hazard. Heretofore, all such devices provided extensions or handles by which the cartridge fuse could be grasped without providing any insulation or protection between the installer and the exposed clips, thus presenting a hazard of shock and shorting across the adjacent clips during installation. Since most usually when a fuse is removed it is for diagnosis purposes, it is generally desirable to have in convenient arrangement a replace ment fuse of the same rating and dimensions to replace the removed fuse if such fuse appears to have burned out. Heretofore, the prior art devices generally did not provide such a replacement, thus requiring that the installer carry an inventory of assorted fuses for replacement.

SUMMARY OF THE INVENTION staller from the exposed terminals of the fuse clips.

Other objects of the invention are to provide within the 2 general confines or dimensions of the fuse holder, a second or replacement fuse disposed for immediate insertion in the fuse clip.

Briefly these and other objects are accomplished within the present invention by forming of a resilient or partly resilient material having high dielectricor insulating properties a fuse holder including a fuse holding hollow cylinder having the interior diameter-thereof confonned to receive the-insulated portion of a standard cartridge fuse, the interior opening being further chamfered at either end and split longitudinally to per mit expansion thereof, thus allowing the larger diameter end caps to be passed therethrough. Formed along one side 'of the cylinder, and in longitudinal alignment therewith, is a handle for manual grasping. Formed at the distal ends thereof are end shields which are disposed to surround the respective end caps of the fuse when such fuse is inserted. The end shields are open at the bottom to permit insertion of the fuse for retention thereof by fuse clips. The distally opposed surfaces of the respective end shields are pierced to form circular openings in concentric relationship with the central axis of the cylinder, the diameters thereof conforming to the largest diameter of the cartridge fuse.

In one other embodiment of the present invention, the handle has formed thereon a second cylinder, also split and chamfered to receive a cartridge fuse includ- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view in partial cross section of a fuse holder embodying the present invention;

FIG. 2 is a bottom view of the fuse holder shown in FIG. 1;

FIG. 3 is a cross sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a side view in partial cross section of yet another embodiment of a fuse holder of the present invention; and

FIG. 5 is a cross sectional view taken along line 5-5 of FIG. 4.

DESCRIPTION OF THE PREFERRED I EMBODIMENTS As shown in FIG. I, a fuse holder 10, formed of an elastic or partly elastic material having high dielectric or insulating properties, such as plastic and the like, comprises a fuse retaining cylinder 11 enclosing a cylindrical cavity 12 sized to conform with the dimensions of the insulator barrel of a conventional cartridge fuse 15. At either end the cavity 12 forms chamfered

annular surfaces

17 and 18 diverging at the outer edges thereof to a diameter greater than the diameter of end caps 15 a and 15b of fuse l5. Fuse 15, at end caps 15a and 15b, is insertable into associated terminals or spring clips 19a and 1% attached to the mounting structure of a conventional fuse clip 19. Formed on 3 one side of cylinder 11, in longitudinal alignment therewith and in substantial opposing relationship with fuse clip 19 is a handle 20, shaped substantially as planar structure projecting radially away from cylinder 11. At the free edge, and proximate the ends thereof, handle 20 expands to form in perpendicular arrangement surfaces or

lips

21 and 22 to facilitate grasping of the fuse holder and for removal of fuse from fuse clip 19 and to provide surfaces for exerting pressure during installation. At the juncture with cylinder 11 handle 20, at both ends thereof, extends to form insulator housings a and 20b, forming walls to surround the exposed end caps of fuse l5 and opening at the surface adjacent fuse clip 19 to receive spring clips 19a and 19b. The distally opposed surfaces of housings 20a and 20b are pierced to form circular openings 23a and 23b aligned concentrically with the central axis of cavity 12 and sized to pass fuse 15 into cavity 12.

As shown in more detail in FIGS. 2 and 3, cylinder 11 is split longitudinally to form a separation thereby allowing circumferential expansion of the cylinder to allow passage of the larger end caps of fuse 15 therethrough. The respective insulator housings20a and 20b are sized substantially to accommodate the respective ends of fuse 15 and the correspondingfuse clips (not shown in this figurelallowing for successive replacement of fuses where one fuse expells the preceding fuse. In this manner, housings 20a and 20b, when installed, provide shielding in all areas at which spring clips 19a and 19b would be accessible by the installer during installation of an adjacent fuse.

Yet another embodiment of the present invention is illustrated in FIG. 4 showing a fuse holder 30 including a first and second

fuse retaining cylinder

31 and 32 constructed substantially similar to cylinder 11 of FIG. 1.

Cylinders

31 and 32 extend from a central planar member 33 in a substantially parallel alignment, where the distal ends of member 33 extend to form a first and second opposed insulative shield housing 330 and 33b forming

opposing chambers

34a, 35a and 34b and 35b across respective common walls 36a and 36b. Walls 36a and 36b form a plane across the ends of member 33 in a substantially equidistant position from the central axes of

cylinders

31 and 32, separating the respective chambers 34a and-34b and chambers 35a and 3512 from each other. v

As previously described, cylinder 31 forms a cavity 44 dimensioned to conform with the insulator barrel of a first cartridge fuse 38, the respective end caps of fuse 38 engaging spring clips 40a and 40b of a conventional fuse clip 40. Similarly, cylinder 32 encloses a spare fuse 39, of a size and power rating equal to fuse 38, providing an immediately replacement available upon failure of fuse 38. The distally opposite surfaces of chambers 34a and 34b and-chambers 35a and 35b are pierced with circular openings 41a and 41b and

openings

42a and 42b each respectively formed in concentric alignment with the central axes of the

corresponding cylinders

31 and 32.

Openings

41a and 41b and 42a and 42b are sized to pass the end caps of the

fuses

38 and 39, allowing for insertion of the fuses into

cylinders

31 and 32. As shown in more detail in FIG. 5,

cylinders

31 and 32 are split longitudinally to form separations 31a and 32a, allowing the respective cylinders to expand or enlarge while passing the end caps of

fuses

38 or 39. In a similar manner to that shown in FIG. 1, the distal ends of

cylinders

31 and 32 are chamfered to a diameter greater than the diameter of the respective end caps, accommodating insertion of the fuse and expanding of the respective cylinder chambers.

In operation, the respective clinders 31 and 32 receive fuses through the coaxial opening formed in the distally opposed walls of the shield housings 33a and 33b being pressed to a position where the respective end caps of the fuses are exposed for insertion into the corresponding spring clips. The removal and reinsertion of any fuse can be accomplished by any conventional tool such as a round bar (not shown) of sufficiently small diameter to pass through the openings. Furthermore, the concentric alignment of the openings and the respective cylinders allows for a sequential replacement of successive fuses where one fuse is used to force out the previous fuse. Installation and withdrawal of the fuse retained in the first fuse holder is facilitated by lips or surfaces 21 and 22 extending from the handle. Similarly, withdrawal and installation of fuses contained in the second fuse holder is facilitated by the enlargements of the respective cylinders, where one cylinder can be used as a handle to force installation or withdrawal of the fuse contained in the other cylinder.

Some of the many advantages of the present invention should now be readily apparent. In one of its embodiments, the present invention provides for a fuse holder, easily manufactured or cast from any partly elastic or elastic material, such as plastic and the like, which also has a high dialectric or insulative quality, providing the insulator shielding around the exposed spring clips and thereby protecting the installer from shock or any possibility of shorting. Furthermore, the expansive character of the respective cylinders of the fuse holders allows for a relatively low accuracy method of construction such as, for example, a casting while at the same time providing a convenient method of installation of a cartridge fuse.

Various modifications and changes may be made with regard to the foregoing detailed description without departing from the spirit of the invention.

What is claimed is:

l. A fuse holder for receiving cartridge fuses disposed for insertion in fuse clips, comprising in combination:

a first resilient cylinder incuding a first central cavity conformed to longitudinally receive the insulative cylinder of a first cartridge fuse;

handle means attached to said cylinder and disposed longitudinal therewith in radial projection for providing insulative manual grasping and pressing surfaces; and

first end insulator means attached to said handle means at both ends thereof formed to partly surround the exposed ends of the first fuse receivable in said cylinder and adapted to receive corresponding terminals of a fuse clip disposed for attachment with said first fuse for providing insulative walls thereabout, said walls including openings for passing said first fuse into said first central cavity.

2. A fuse holder according to claim 1, wherein:

said first end insulator means is formed with an opening disposed in substantially opposing relationship with said handle means for receiving the terminals of said fuse clip.

3. A fuse holder according to claim 2, wherein:

said first resilient cylinder further includes annular chamfers formed in the distal ends of said first cen- 'tral cavity and diverging to a diameter greater than the end diameter of the receivable fuse at the end surfaces of said first cylinder, and a separation formed longitudinally in the wall of said first cylinder.

4. A fuse holder according to claim 3 wherein:

said openings further include circular apertures formed in the distally opposed walls of said first end insulator means in concentric alignment with said first cylinder and of a diameter greater than the exterior diameter of said fuse.

5. A fuse holder according to claim 4, wherein:

said handle means further includes a first insulative planar member attached at one edge thereof to said cylinder and projecting readially therefrom and a second planar member attached in substantially normal alignment with said first planar member proximate the distal ends of the other edge thereof? 6. A fuse holder according to claim 2, wherein:

said handle means further includes a second resilient cylinder formed in parallel alignment with said first resilient cylinder and including a second central cavity conformed to longitudinally receive the insulative cylinder of a second cartridge fuse and second insulator means attached to said handle means at both ends thereof formed to surround the exposed ends of the second fuse receivable in said second cylinder including openings on the distally '6 opposed surfaces thereof for passing said fuse into said first and'second cavity and adapted to receive corresponding terminals of a fuse clip in substantially opposing relationship with said first end insulator means for providing insulative walls thereabout.

7. A fuse holder according to claim 6, wherein:

said first and second end insulator means is formed 9. A fuse holder according to claim 8, wherein: said openings in said first and second end insulator means further include circular apertures formed in the distally opposed walls thereof in concentric alignment with said first and second cylinders and of a diameter greater than the exterior diameter of said fuse.

Claims

1. A fuse holder for receiving cartridge fuses disposed for insertion in fuse clips, comprising in combination: a first resilient cylinder incuding a first central cavity conformed to longitudinally receive the insulative cylinder of a first cartridge fuse; handle means attached to said cylinder and disposed longitudinal therewith in radial projection for providing insulative manual grasping and pressing surfaces; and first end insulator means attached to said handle means at both ends thereof formed to partly surround the exposed ends of the first fuse receivable in said cylinder and adapted to receive corresponding terminals of a fuse clip disposed for attachment with said first fuse for providing insulative walls thereabout, said walls including openings for passing said first fuse into said first central cavity.

2. A fuse holder according to claim 1, wherein: said first end insulator means is formed with an opening disposed in substantially opposing relationship with said handle means for receiving the terminals of said fuse clip.

3. A fuse holder according to claim 2, wherein: said first resilient cylinder further includes annular chamfers formed in the distal ends of said first central cavity and diverging to a diameter greater than the end diameter of the receivable fuse at the end surfaces of said first cylinder, and a separation formed longitudinally in the wall of said first cylinder.

4. A fuse holder according to claim 3 wherein: said openings further include circular apertures formed in the distally opposed walls of said first end insulator means in concentric alignment with said first cylinder and of a diameter greater than the exterior diameter of said fuse.

5. A fuse holder according to claim 4, wherein: said handle means further includes a first insulative planar member attached at one edge thereof to said cylinder and projecting readially therefrom and a second planar member attached in substantially normal alignment with said first planar member proximate the distal ends of the other edge thereof.

6. A fuse holder according to claim 2, wherein: said handle means further includes a second resilient cylinder formed in parallel alignment with said first resilient cylinder and including a second central cavity conformed to longitudinally receive the insulative cylinder of a second cartridge fuse and second insulator means attached to said handle means at both ends thereof formed to surround the exposed ends of the second fuse receivable in said second cylinder including openings on the distally opposed surfaces thereof for passing said fuse into said first and second cavity and adapted to receive corresponding terminals of a fuse clip in substantially opposing relationship with said first end insulator means for providing insulative walls thereabout.

7. A fuse holder according to claim 6, wherein: said first and second end insulator means is formed with an opening disposed in substantially opposing relationship for receiving the terminals of said fuse clip.

8. A fuse holder according to claim 7, wherein: said first and second resilient cylinders further include annular chamfers formed in the distal ends of said first and second central cavities diverging to a diameter greater than the end diameter of the receivable fuse at the end surfaces of said first and second cylinders and a separation formed longitudinally in the wall of said first and second cylinders.

9. A fuse holder according to claim 8, wherein: said openings in said first and second end insulator means further include circular apertures formed in the distally opposed walls thereof in concentric alignment with said first and second cylinders and of a diameter greater than the exterior diameter of said fuse.