US1712738A

US1712738A - Attachment-plug cap

Info

Publication number: US1712738A
Application number: US282357A
Authority: US
Inventors: Arthur S Spidel
Original assignee: E A HAMILTON
Current assignee: E A HAMILTON
Priority date: 1928-06-02
Filing date: 1928-06-02
Publication date: 1929-05-14
Anticipated expiration: 1946-05-14

Description

y 14, 1929- A. s. SPIDEL ATTACHMENT PLUG CAP Filed June 1928 fltoz, S pide/ I ammq Patented May 14, 1929,

UNITED STATES 1,712,133 PATENT OFFICE.

ARTHUR S. SPIDEL, OF BREWSTER, OHTO, A SSIGNOR 0F ONE-HALF TO B. A. HAM- ILTON, OF NAVARRE, OHIO.

ATTACHMENT -'.PLUG CAP.

Application filed June 2, 1928. Serial No. 282,357.

My invention relates to the caps of separable attachment plugs for electric cables and the like, and more particularly to caps including an inneraoontact blade mounting member of relatively rigid insulating material, and an outer protective covering therefor of relatively resilient material,

- whereby the cap may be dropped without breaking. I

Such plug caps as ordinarily made 1nclude for the blade mounting member, a rigid disk of insulating material, which may be bakelite, andwhich is provided with a relatively large central opening through which the cord is inserted for attachment to the binding screws of the contact blade base plates.

The usual resilient cover for the disk is made of soft rubber and is in the shape of a dome having a central aperture at its crown forreceiving the cord, and is internally secured near its base to the periphery of the disk. A

The central openings in the disks of attachment plug caps thus constructed, very materially weaken the same. Moreover such plug caps, while being adapted for the proper connection of the cable cords by leading or snubbing' the cords around the contact blades and passing them over the top of the contact blade base plates to the binding screws, are also adapted for improper connection of the cable cords with the contact blades by leading the cords directly to the binding screws from the center of the cap without snubbing the cords around the contact blades and without passing them over the top of the contact blade base plates in the proper manner.

It is desirable to snub the cords around the contact blades and lead them over the top of the contact blade base plates to the binding screws to avoid short circuits, and to minimize the strain on the binding screws caused by applying a tension to the cable attached to the plug cap.

Accordingly the objects of the present improvements include the provision of an at tachment plug cap including a rigid blade mounting member and a resilient dome cover therefor and in which the blade mounting member is in a form which is structurally much stronger than the usual apertured disk, and is also provided with cord guide members which will permit the attachment of the cable cords to the contact blades of the plugs only by the proper method of snubbing vthe cords about the contact blades and leading'them over the top of the base plates to the binding screws.

These and ancillary objects are attained in the present improvements by a construction and arrangement which will be hereinafter set forth in detail and claimed.

Preferred embodiments of the invention are illustrated in the accompanying drawing formingpart hereof, in which Figure 1 is a blade end view of one em bodiment of the improved plug cap;

Fig. 2, a vertical cross section thereof as on line 2-2, Fig. 1;

Fig. 3, a detachedsectional view of the improved blade mounting member therefor, as on line 3+3, Fig. 4;

Fig. 4, an elevation view thereof as in the direction of the arrows 4-4:, Fig. 3; and

Fig. 5, a View similar to Fig. 2 of a modified embodiment of the improved plug cap.

Similar numerals refer to similar parts throughout the drawing.

The improved attachment plug cap indicated generally at 10 includes a rigid blade mounting member 11, which may be made of insulating material such as bakelite, and which is secured at its periphery 12 in an internal annular groove 13 of a dome 14, which may be molded of a soft rubber or other resilient material.

Contact blades 15 having base plates 16 are secured in a usual manner upon one side of the blade mounting member 11. The blade mounting member 11 may be in the form of a disk 17 having a propeller-like cord guide member 18 secured at the side of the disk upon which the contact blades are mounted and which may be preferably molded integral with the disk.

The disk is provided with spaced apertures 19 having formed inner surfaces 20 which merge with surfaces of the cord guide member 18 for forming guideways for the cords 21 of a cable 22. An axial aperture 23 is provided in the crown of the dome 1a through which the cords 21 extend-before passing through the mounting member apertures 19.

The propeller-like cord guide member 18 is centrally wide enough to act as a spacer for the contact blades 15, and opposite sides of the opposite ends, of the guide member guide member provides an eflicient insulation between the bare ends 26 of the cords. It is to be understood that the particular type of attachment plug ca herein set forth,

and including the soft ru ber dome, is de signed for rough usage where the cap is likely to be dropped on a hard floor, when the cap would break if the dome were made of the usual bakelite material or similar composition.

I claim:

1. An attachment plug cap including an outer protective cover of relatively resilient material, and an inner contact blade mounting member of relatively rigid material secured within the cover, the mounting member having spaced cord apertures therein.

2. An attachment plug cap including an outer protective cover of relatively resilient material, and an inner contact blade mounting member of relatively rigid material secured within the cover, contact blades including base plates secured on the mounting member, and the mounting member havin spaced cord apertures therein, and the cor apertures having faces forming guideways for snubbing cord wires about the contact blades and directing them over the base plates.

3. An attachment plu cap including an outer protective cover of relatively resilient material, and an inner contact blade mounting member of relatively rigid material secured within the cover, the mounting member having spaced cord apertures therein, and contact blades secured on the mounting member.

4. An attachment plug cap including an outer protective cover of relatively resilient material, and an inner contact blade mounting member of relatively rigid material secured within the cover, contact blades including base plates and binding means secured on the mounting member, and the mounting member having spaced cord apertures therein, and the cord apertures havin faces forming guideways for snubbing cord wires about the contact blades and directing them over the base plates.

In testimony that I claim the above, I have hereunto subscribed my name.

ARTHUR S. SPIDEL.