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Publication numberUS1810305 A
Publication typeGrant
Publication dateJun 16, 1931
Filing dateJun 29, 1929
Priority dateJun 29, 1929
Publication numberUS 1810305 A, US 1810305A, US-A-1810305, US1810305 A, US1810305A
InventorsScherer Francis R, Tracy John M
Original AssigneeProse Maco Mfg Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Locking device for blackboards
US 1810305 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

June 16, 1931. J. M. TRACY ETAL 1,810,305

LOCKING DEVICE FOR BLACKBOARDS Filed June 29, 1929 Ill I y Fmmms R,5 3 2 ,4/





The present invention, relates to locking devices for movable exhibitors and consists in the combinations and arrangements of elements hereinafter described and particularly set forth in the accompanying claims.

The invention has for its purpose to provide a locking device for hinged. frame structures, but more particularly for swinging blackboards, to the end that the same may be securely held in their closed or. concealed position and therefore the matter written or otherwise exhibited thereon may not be left liable to unauthorized inspection, erasure, or for other interference.

The invention is designed as an improvement for use in connection with our U. S. patent on Blackboard, described in Patent No. 1,5.96,d57, dated August 17, 1926, and from-an inspection of which the applicability of the present invention will be apparent.

The ,inventionis shown by way of illuss tration in the accompanying drawings, wherein:

Figure 1 is aperspective view showing the locking device in applied position.

Figure 2 a detailed view showing the locking device in releasedposition.

Figure 3 a detailed view showing the looking device, per $6.:

Figure 4 a side .elevational view thereof, and;

Figures 5 and 6 illustrate a modified construction. 7

Referring to the construction in further detailthe invention consists of a hollow post 5 suitably secured to a base plate 6 adapted to be fastened to the wallorfother structure on which the several blackboard frames or panels A are hingedly mounted and immediatelyadjacent thereto as shown in F igure 1.

A stud 7 is screw threaded in the hollow post portion 5 and has its adjusted position secured therein by theset screw 8 as shown in Figures 3 and 4. The outer end of stud .7 is reduced as at .9 to receive the bifurcated end 10 of the swingin arm 11 which is constructed preferably 0 fiatlike metal as shown.

LOCKING DEVICE ron. BLAc BoAnns 1$ J29. Serial No. 374,778.

tangular shaped aperture 13 adapted to receive the boss 14 that forms an integral part of the bracket 15 that is securedto the lower and outer corner of the frame B of the black board A as indicated in Figure 1. Said corner bracket 15 may be located on either the-upper or lower corner of the frame and the boss 14; thereof may project from the side of said bracket :if preferred.

When the several frames or blackboards are swung to one side as shown in Figure 1 the swinging arm 11 is brought to engage the boss 14 and in this position the hasp 16 of the padlock 17 is passed through the aperture of the boss and thus the sevoral leaves or frames of the blackboard are secured free from disturbance for reasons heretofore stated.

Referring to Figures 5 and6 the device consists of a similar hollow post .5, having a stud or arm/7 screw-threaded thereon as in .the former construction, and the free end of said'post or arm 7 is apertured as at 18 to engage the boss of the innermost frame or blackboard section. A plurality of, hinged link members 19 have hinged support 20 with the rigid arm 7 and the opening in each link is adapted to receive the boss 14- of the bracket frame 15 as above described.

It will therefore be seen that with this modified construction the locking device is adapted to engage and secure one, two, three or four of the blackboards, as desired, and thus leave the remainder free. In allother respects the construction of device and its manner of operation are identical with that above described. i

It will be understood by those skilled in the art that changes may be made in our device without departing from the spirt of the invention andtherefore we do not limit ourselves to the precise construction shown in the drawings and described in the specification but only asindicated in the appended claims.

What. is claimed as new is:

1. The combination with a plurality of for comprising a fixedly mounted socket piece, an arm rigidly mounted in the socket piece, and a plurality of links on said arm adapted to engage with said exhibitors, for the purpose set forth.

2. A device of the character described comprising a socket piece adapted to be fixedly mounted on a support, a rigid arm screw-threaded into said soc-ket'piece, and a plurality of link members mounted on said rigid arm for the purpose set forth.

3. The combination with a plurality of hingedly mounted frames or panels, and a support; of a locking device for said frames comprising a socket piece mounted on the support, a hasp mounted on the socket piece, and a lug on the outermost frame adapted to engage said hasp and hold all of the frames against swinging movement, substantially as set forth.

In Witness whereof, we have hereunto set our hands at Rochester, N. Y., this 14th day of June, A. D. nineteen hundred and twentynine.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2860224 *Oct 28, 1955Nov 11, 1958St Joe Machines IncPortable utility
US5722268 *Apr 23, 1996Mar 3, 1998Samsung Electronics Co., Ltd.Burglar-proofing device for a personal computer
U.S. Classification434/414, 70/57
International ClassificationB43L1/04, B43L1/00
Cooperative ClassificationB43L1/04
European ClassificationB43L1/04