US2701347A

US2701347A - Electrical socket having a movable cover

Info

Publication number: US2701347A
Application number: US387453A
Authority: US
Inventors: Davidsson Tage Arnold
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-12-23
Filing date: 1953-10-21
Publication date: 1955-02-01
Anticipated expiration: 1972-02-01
Also published as: NL83345C; BE524383A; CH316003A; FR1086683A; GB732027A

Description

Feb. 1, 1955 T. A. DAVIDSSON 2,701,347

ELECTRICAL SOCKET HAVING A MOVABLE COVER Filed Oct. 21, 1953 IN VEN TOR.

ATTORNEYS United States Patent ELECTRICAL SOCKET HAVING A MOVABLE COVER Tage Arnold Davidsson, Gothenburg, Sweden Application October 21, 1953, Serial No. 387,453

Claims priority, application Sweden December 23, 1952 3 Claims. (Cl. 339-40) The present invention relates to electrical pin-andsocket couplings of the kind provided with a cover plate situated in front of a pair of socket tubes adapted to receive the pins of a plug and provided with openings registering with the socket tubes, and in which there is provided a movable spring-actuated shutter mechanism behind the cover plate and adapted to uncover the socket tubes by being simultaneously actuated on the insertion of the two plug pins.

The object of devices of this character is to prevent children and others from making contact with live parts of the coupling.

Devices of this kind already known, in which the openings in the front plate have the form of circular holes conforming with the plug pins, suffer from the disadvantage that they must of necessity be comparatively thick owing to the fact that an axial movement of the plug pins is required for operating the shutter mechanism.

The object of the present invention is to overcome this disadvantage, and said invention is broadly characterised in that the openings in the cover plate consist of elongated parallel slots each having one end in register with one of the socket tubes, the shutter mechanism being so disposed in relation to the slots, that it is brought to a position uncovering the socket tubes by moving the plug pins along the slots in a direction towards the ends thereof which are disposed over the socket tubes.

In such a device the socket coupling can be constructed with a comparatively small dimension in a direction perpendicular to the plane of the cover plate, and in addition the further advantage is obtained, viz: that it is easy to find the socket tubes with the plug pins by using the slots as guides.

In the accompanying drawing there is shown an embodiment of the invention, and in said drawing:

Figure 1 shows a front view of a socket coupling according to the invention with the shutter mechanism in the safety position;

Figure 2 shows the shutter mechanism as seen from the back, also in the safety position;

Figure 3 is a view mainly corresponding to Figure 2 but with the shutter mechanism in a position uncovering the socket tubes;

Figure 4 is a cross section through the device along the line IV--IV in Figure 2, and

Figure 5 is a perspective view of a detail of the shutter mechanism.

The base plate carrying the socket tubes is not shown in the drawing and can be of any suitable design.

In the drawing 1 denotes a cover plate securable to a base plate by means of screws 2 and provided on its front face with a circular recess 3, the bottom of which is pierced with two elongated, parallel slots 4 and 5, each having one end in register with one of the socket tubes 6, 6a (indicated by dotted lines in Figure 4). In a roughly U-shaped recess in the back of the cover plate there are housed two similar shutters 7 and 7a respectively, which are slidable in a direction perpendicular to the axis of the slots 4, 5. As shown in Figure 5 the shutters consist of thin U-shaped plates with parallel shanks 9, l0 and 9a, 10a respectively of unequal length, of which the longer 9 (9a) is obliquely cut off at its free 2,701,347 Patented Feb. 1, 1955 Ice end so as to form a slopping edge 11 and 11a respectively. The bases and short shanks of the shutters overlap each other and are guided by opposite walls 12 and 12:: respectively, of the recess A. Each shutter is pressed by a spring 13 and 13a respectively, which normally hold the shutters in the position shown in Figures 1 and 2 in which position the shank 9 of the shutter 7 covers the socket tube 6 and the shank 10 of the same shutter covers the socket tube 6a, while the shanks 9a and 10a of the shutter 7a in a similar way also cover the socket tubes. In this covering or safety position of the shutters the sloping edges 11, 11a of the longer shanks 9, 9a cross the two slots 4, 5 obliquely at a distance from the ends situated on the periphery of the recess 3, so that by inserting the plug pins (indicated by dotted lines 14 in Figure 3) in said ends of the slots 4, 5 and sliding the same along the slots to their opposite ends the shutters 7, 7a will be moved against the action of the springs 13, 13a to the position shown in Figure 3. By this displacement of the shutters 7, 7a their shanks uncover the socket tubes 6, 6a, so that the plug pins 14 can be pushed home in the socket tubes 6, 6a. Behind the cover plate 1 there is secured a bottom plate 15, which is partly broken away in Figure 2 and entirely removed in Figure 3, and which is provided with holes 16 registering with the socket tubes 6, 6a.

The invention is not limited to the embodiment described above and shown in the drawing but may be varied in detail without departing from the spirit of it. For instance, the shutters may be pivotally mounted instead of slidable.

What I claim is:

1. An improvement in cover plates for electrical plug and socket couplings wherein said socket has tubes for receiving pins of said plug comprising a cover plate having elongated substantially parallel slots positioned for having one end thereof registering with the tubes of said socket, when said cover plate is mounted thereon, a pair of plates each slidably mounted on said cover plate for movement substantially parallel to said cover plate laterally of said slots, each of said plates having a shoulder extending from an end thereof, resilient means tending to position said plates covering the tube registering portion of said slots with each shoulder extending diagonally of one of said slots for being engaged by said plug pins when moving longitudinally of said slots whereby said plates are moved from their tube covering position.

2. An improvement in cover plates for electrical plug and socket couplings wherein said socket has tubes for receiving the pins of said plug comprising a cover plate having elongated substantialy parallel slots each for being in register at one end with one of said tubes when said cover plate is mounted over said socket, a pair of fiat substantially U-shaped plates slidably mounted on said cover plate with one leg extending longitudinally of one of said slots covering the tube registering portion thereof and having the end of said leg thereof extending diagonally of its corresponding slot, resilient means tending to retain said plate legs in their slot covering position whereby said diagonal end can be contacted by said plug pins when moving longitudinally of said slots displacing said plates laterally and opening said slots.

3. An improvement in cover plates as claimed in claim 1, wherein said cover plate has recesses provided therein for guiding said plates to and from their slot covering positions.

References Cited in the file of this patent UNITED STATES PATENTS 1,736,269 Lawrence Nov. 19, 1929 FOREIGN PATENTS 508,415 Great Britain June 30, 1929