US2946864A

US2946864A - Locking apparatus

Info

Publication number: US2946864A
Application number: US802115A
Authority: US
Inventors: Kenneth J Marien
Original assignee: Square D Co
Current assignee: Schneider Electric USA Inc
Priority date: 1959-03-26
Filing date: 1959-03-26
Publication date: 1960-07-26
Anticipated expiration: 1977-07-26

Description

July 26, 19 60 K. J. MARIEN 2,946,864

LOCKING APPARATUS Filed March 26. 1959 2 Sheets-Sheet 1 Fl 7 l INVENTOR.

KENNETH J MARIEN July 26, 1960 K. J. MARIEN 2,946,864

LOCKING APPARATUS Filed March 26. 1959 2 Sheets-Sheet 2 III! I IIIA E i Y N Q s i g .1

M Q 1 iv n g I. a

INVENTOR.

KENNETH J. MARIEN United States Patent t) LOCKING APPARATUS Kenneth J. Marien, Milwaukee, Wis., assignor tosquare D Company, Detroit, Mich., a corporation of Michigan Filed Mar. 26, 1959, Ser. No. 802,115

6 Claims. (Cl. 200-42) This invention relates to a locking arrangement for switch boxes which will prevent operation of the switch, and entry into the switch box, as well as partial and complete removal of the cover from the box. It is well recognized in the electrical industry that operation of an electrical switch by unauthorized personnel must be guarded against. It is also recognized that entry to the current conductive parts of the switch niust be prevented so that unauthorized persons will not be endangered.

In the past various types of locking devices, which use padlocks, have been incorporated to prevent complete removal 'of the cover of a switch box. Other locking devices have been designed which would lock the operating handle to the switch box so that the handle could not be moved relative to the box for operation of the switch when the padlock was attached thereto. In those prior devices wherein the cover was locked to the box, it was possible to operate the switch,'if the switch operating member extended through the cover, and in those devices wherein the-switch operating lever was locked, it was possible to at least partially remove the cover from the box. When the cover can be partially removed from the box an unauthorized person can poke a wire or tool between the cover and box, and either pry the cover away and bend it, or hit one of the live terminals in the switch and get a shock;

The present invention has for one of its objects the provision of a simple, inexpensive, and fool-proof arrangement of cooperative parts, which provide a switch box with locking features to prevent unauthorized operation of, the switch, and unauthorized entry into the box, as well as unauthorized partial and complete removal of the cover.

Another object of the invention is to provide a switch box for pushbutton type switches with a cover which is secured to the box by an element, and also to provide the cover with a latch rotatable to an operatively aligned position at least partially overlying that element and one of the pushbuttons.

Another object of the invention is to provide the cover of a pushbutton type switch box with a latch which may be positioned to simultaneously interfere with operation of the pushbutton and removal of the cover.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings in which:

Figure 1 is a front view of a switch box incorporating the features of the present invention;

Figure 2 is a fragmentary enlargement of that portion of the box supporting the latch member; and

Figure 3 is a sectional view taken approximately along the line 3-3 of Figure 2.

The description, drawings, and claims jointly set forth one or more embodiments of the present invention, and the present contribution to the art of making electrical apparatus safe.

As illustrated, the switch comprises a box 10 having a cover 11 removably attached to the box and cooperating therewith to enclose a suitable switching device 12. The details of construction of the switching device or switch 12 will not be described other than to point out that the switch 12 has one or more suitable switch operating means, such as a pushbutton 13, which extends through an opening 14 in the cover '11.

The box 10 includes a wall 10 which supports a hasp receiver 15'. The hasp receiver 15 extends through an opening 16 in one edge of the cover and terminates in an outwardly extending hasp receiving portion 17 provided with a hasp receiving hole 18. The portion 17 is aligned substantially parallelwith the wall 10' of the box 10. In

hasp receiver 15 with a U-shaped center portion 19 providing spaced parallel portions 20 and 20' which extend transverse to the wall 10 of the box It), and which are provided with bolt or element receiving holes 21 and 21' respectively. The cover 11 is also provided with an element receiving hole 23 which is aligned with these holes 21 and 21' so that a threaded bolt or other suitable fastening element 24 may be inserted through the cover and into the

holes

21 and 21 to secure the cover onto the box 10. In this instance bolt 24 extends through

holes

23 and 21 and is threaded into hole 21'.

Referring to Figures 2 and 3, it is noted that the hasp receiving opening 18 of the hasp portion 1'7, element or bolt 24 and the pushbutton 13 are aligned so that a single latch member 25 may be pivoted on the cover to a position wherein it Will be operative to prevent unauthorized entry into the box, as well as unauthorized operation of the pushbutton 13. To accomplish this feature the latch member 25 is pivotably mounted by means of a rivet 26, or other suitable element, to the cover at a position between the pushbut-ton opening 14 and the element receiving hole 23; H-asp receiving member 17, pushbutton 13, and the point of pivotal connection of latch member 25 to cover 11, are disposed in a single plane. This latch member 25 has one end 27 engageable with the pushbutton 13 to prevent operation of the pushbutton and has an opposite end 28 provided with a hasp receiving opening 29 alignable with the hasp receiving opening 18.

, When the latch member 25 is in the operatively aligned position, as indicated in the solid lines in Figures 2 and 3, the hasp of a lock (not illustrated for purposes of clarity) may be inserted through the

hasp receiving openings

18 and 29 to prevent turning of themember 25 relative to the cover 11. In the description and claims, the term operatively aligned means that position in which the member 25 is in the line of movement of bolt 24 during its insertion or removal into holes 21 and 21', as Well as in the line of movement of the operating means or member, 13, during its function of operating the switch 12. While the latch member 25 is in this operatively aligned position, the end portion 27 at least partly overlays, and thereby interferes with or prevents operation of the pushbutton 13, and the end 29, or a hasp inserted therethrough, at least partly overlays and thereby interferes with or prevents removal of the bolt or element 24. Since the element 24 cannot easily be removed, the cover cannot easily be lifted from the box, regardless of the length, size or configuration of the hasp on the padlock.

Operation of the switch or entry to the box is readily made possible by simply removing the padlock and then turning the member 25 out of the operatively aligned position so that the end portion 27 is free of and not overlaying the pushbutton 13 and so that the end 28 is inoperatively aligned with and thus not interfering with the removal of the element 24. In addition, the padlock hasp may be inserted through hasp receiving hole 18 to secure the cover 11 on the box while the latch member 25 is in the position indicated by dash-dot lines 25 to thereby permit authorized operation of button 13 while preventing unauthorized entry into the box It In the present instance it has been further found advisable to provide the cover 11 with a recess in the front surface thereof so that raised cover portions =30 and 31 are disposed on opposite sides of the button 13 and the latch member 25'. This recessed portion is further defined by a bottom wall 33, which pivotally supports latch member 25, and by spaced opposing and tapered side walls 34 and 35' which are spaced apart so that latch member 25 can be rotated between its operatively aligned and inoperative position. In addition the end 28 of the latch member 25 is bent and positioned at an angle to the recessed bottom wall 33 to facilitate insertion of the hasp through the

openings

18 and 28 when the latch member 25 is in operative alignment and to facilitate turning member 25 in the recess between

side walls

34 and 35.

The raised

portions

30 and 31 extend outwardly from the box a distance greater than the pushbutton 13, the end portion 28, and the hasp receiving portion 17 so that they protect these working parts as well as the latch member 25 against damage.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. In combination with a switch box and cover enclosing a switch having a switch operating pushbutton extending through the cover, the provision of a hasp receiving member secured to and carried by a wall of said box, said hasp receiving member having a free end portion extending outwardly beyond said cover and provided with a hasp receiving opening and also having another portion extending parallel with said cover in a general direction from said free end portion towards said pushbutton and provided with a threaded opening, a threaded element carried by said cover between said pushbutton and said hasp receiving member and threaded in said opening and thereby releasably fastening said.

cover to said hasp receiving element to releasably hold said cover on said box, a latch member carried by and pivoted to said cover at a location between said pushbutton and said threaded element and rotatable relative to the cover to a first position and to a second position,

said member having one end overlaying said-pushbutton and an opposite end overlaying said threaded element when the member is in said first position, said ends being free of and removed from said pushbutton and said element when the latch member is in said second position whereby said pushbutton and said threaded element are rendered usable.

2. The structure as defined in claim 1 wherein said hasp receiving member, pushbutton and location are in a straight line.

3. The structure as defined in claim 1 wherein said opposite end of said latch member, which overlays said element when said latch member is in said first position, is provided with a hasp receiving opening aligned with said hasp receiving member to simultaneously receive a hasp therewith to prevent pivotal movement of said latch member from said first position.

4. The structure as defined in claim 1 wherein said cover has raised portions on opposite sides of said latch member and said button, and extending outwardly beyond said button, and said opposite end of said latch member extends at an angle to said cover and lies along side one of and within the extremities of said raised portions when said lattch member is in said second posi-' tion.

5. In combination with a switch box and cover enclosing a switch having switch operating means, the provision of hasp means secured to said box, an element carried by said cover and engageable to said hasp means to releasably hold said cover on said box, a latch member pivoted to said cover at a point between said operating means and said element and rotatable to a first position and to a second position, said member having one end interfering with said operatiing means and an opposite end cooperative with said hasp means and therewith aligned with said element when the member is in one of said positions to interefere with disengagement of said element from said hasp means, said ends being free of said operating means and saidelement and hasp means when the member is in the other of said positions.

6. The structure as defined in claim 1 wherein said hasp means, pushbutton, and point are in straight line.

References Cited in the file of this patent UNITED STATES PATENTS 2,370,877 Robbins Mar. 6, 1945 2,484,424 Rosing Oct. 11, 1949 2,659,780 Berger Nov. 17, 1953 2,673,259 Appleton et a1. Mar. 23, 1954 2,752,440 Robbins Mar. 18, 1956 2,850,587 Nolden et a1 Sept. 2, 1958