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Publication numberUS382705 A
Publication typeGrant
Publication dateMay 15, 1888
Filing dateOct 31, 1887
Publication numberUS 382705 A, US 382705A, US-A-382705, US382705 A, US382705A
InventorsBlackboard And Wiping
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Blackboard and wiping and dust-collecting apparatus
US 382705 A
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Description  (OCR text may contain errors)

(No- Model.) K 2 Sheet-s-Sheet JpKAND; BDAGKBDADD AND WIPING AND DUST DDLLDGTIDG'APDADAfDsg-f` i No.. 382,705. Patented May `1.5, -1888.



SPECIFICATION forming part of Letters Patent No. 382,705, dated May 15, 1888.

.l i Application filed October 3l, 1887. Serial No. 253,835. (No model.)

To all whom t may @onorari/t:`

Be it knownthat I, JOHN KANE, a citizen of the United States, residing at Green Isle, in the county of Sibley andStateof Minnesota, have invented an Improved 'Blackboard and Wiping and Dust-Oollecting Apparatus connected therewith; and I do hereby declare that the following is afull and exact description of the same, reference being had to the accompanying drawings, making part of this specication. y

My invention consists, first, in a movable blackboard; second, in a blackboard forming an endless movable belt and provided with a crank and roller for4 moving the same; third, in a wiper vvor wiping Vdevice for cleaning! the surface of a movable blackboard orbelt; fourth, in a dustcollecting and holding devicein connection with the traveling blackboard or belt and wiper; fifth, in certain special features of construction in the apparatus. v y

In the accompanying drawings,Figure l represents a' front view of. a blackboard forming an endless movable belt, and of a wiper and dnstcollector in connection therewith in accordance with my invention; Fig. 2,a top view of the same; Fig. 3, a bottomV view thereof; Fig. 4, a horizontal longitudinal section of the same in a planeindicated by the line l 1,Fig. l.

Like letters designate corresponding parts in all of the figures.

Upon a suitable frame, A,which may be built upon the wall of the room or made separate and attachable to any wall, is mounted the back board or plane firm surfaced backing B. The separately-constructed frame and back board, as represented in the drawings, is preferred, and this may be of any desired length and of proper width. If too long for convenient transportation, the frame may be jointed for folding up in any known manner y for other frames or structures. This frame comprises or may comprise a shelf or box, G, for holding chalk or crayons. At or near'the two extremities of the frame are mounted two rollers, DE, as shown, or in any other equivaf lent manner. Upon these rollers is mounted anendless belt or apron, G, of canvas or any other suitable exible material,which serves as the blackboard proper-that is, furnishes the writing-surface of the blackboard. For

this purpose it'has theA proper finish for a surface to write with ohalk'or crayons upon,pre pared in lany way known y to those skilled in the art.` This endless belt or, apron also is to have sufficient firmness and rigidity to keep its position and shape when it is properly stretched upon its rollersD E vertically edgewise, and not to sag down out of proper form and place, generally with the assistance lof a hem or thickness at the upper edge. VIt-s front or exposed portion is located closely in frontr of the back board, B, as shown in Fig. 4, so 7 that the canvas belt may present a firm surface to the chalk by means of this backing.

.One ofthe carrying-rollers, as D, is mounted' Ain* suitable bearings, r vr, which are adjustable longitudinallyon the frame for tighten- :ingnthe 4canvas.' sufficiently upo'n'the rollers. The means of adjusting the bearings isor Amay be byl slots a a in the bearings andi setscrews `b b, passed through the slots and screwed into the frame, this being a suitable and Well-known device for such a purpose. The other roller, as E, on which the endless belt is' mounted, has its periphery covered with a thickness, c, of india-rubber, or any other material which furnishes a frictional surface sufficient to cause v vthe belt to move as the said roller is turned around. In addition to this, I provide, when necessaryordesirable,anoutsidecounter-press ure roller, I, the bearings d d of which turn in ibearings H H, which slide in slots e ein some .parts of the frame, whereby .the roller maybe pressed against the carrying-roller E, so as tof f press the canvas or fabric ofthebelt between the two rollerswith sufficient pressure to prevent the slipping ofthe belt as the carrying-roller is turned. Suitable springs are employed to press the roller I toward the roller E. I have shown two springlevers,J J ,or somewhat iiexi =ble and elastic rods, as shown, each pivotedf at one end at one side of the slotted bearing,

and the other end having aghook or projection, f, to take into one of a 'series of adjusting-holes, g g, in the frame, as shown inFg's. 2 and 3,0r otherwise. Thesprings are suitably adjusted in tension by means of these holes, either one being adapted to receive the'hook end of the spring. Y

The belt-moving rollerEis caused to revolve for moving the endless belt alongby any suitable mechanism. I have shown a gearing by which the roller is made to revolve by means of a crank or winch, K, situated in a suitable place on the frame of the blackboard and turned by hand. On the shaft of the crank is a gear-wheel, h, gearing into a pinion, t', on a shaft, L, and on this shaft, preferably at the other end, is a sprocketwheel, j, around which a belt-chain, M, travels, as also around another sprocket-wheel, 7c, on the shaft or extended bearing of the said driving-roller E. In order to cause the counterlroller I to turn in unison with the roller E, two pinions, Z m, of equal size, are mounted on the respective shafts or extended bearings of the two rollers. The gearwheel and pinion h and t are preferably bevel gearwheels of such degree of bevel that the shaft of the crank may incline somewhat from a horizontal position and allow the gear-wheel h to incline downwardly backward, as shown in Fig. 3, so that the crank may rest as far backward as possible when it is in its lowest position, and thus be out of the way of persons using the blackboard.

In connection with this movable blackboard or blackboard-belt I employ a wiper,

so that as the belt is caused to move along by rotating the driving-roller E its surface may be cleanly wiped. For this purpose I prefer -to make use of a revolving wiper, N, its revolving motion being in the opposite direction to that of the be1t,against which it rubs. To effect this result, the wiper is mounted on the shaft L, above specified as gearing with the crankshaft, and, this shaft being located back of the endless belt where the said endless belt travels behind the back board, B, or counterroller B', the desired direction of motion is thereby obtained. The surface of the wiper should be of sheeps or lambs pelt or sheeps or lambs wool or equivalent fibrous or soft substance, and it is caused to press elastically against the surface of the endless belt. rlhis wiper or eraser is located in a close chamber, so that the chalk-dust is closely confined therein while the belt is being wiped, and afterward,as the dust accumulates in the chamber, it is from time to time withdrawn therefrom through an outlet covered by a removable door or slide, O, Fig. 3. Provision is or may be made for getting access to the wiper and removal of the saine for repair or renewal of its covering in any suitable manner. The means shown is as follows: The bearings P P of the wiper are of hookA form and pivoted at n n, Figs. 2 and 3, to the frame. These bearings the springs J J the outer ends of the bearings lPMP are swung forward, at the same time unhooking the journals of the wiper from the bearings. To furnish suficient room for the removable of the wiper,one side is or may be removable.

In order to keep the upper edge of the endless belt close to the back board and prevent its stretching and inclining forward out of proper position,it is best to haveits upper edge, hem,or border,p,run behind alip or flange, Q, at the upper edge of the back board. This lip or flange may be of sheet met-al and holds under the hem. The belt where it bends outward in swinging the bearings P P forward is held in place at the upper edge by an overlapping spring-plate, R.

I do not confine my invention to the exact special construction herein set forth.

I claim as my inventionl. The combination of a movable blackboard and automaticallyrotating wiper, for the purpose herein set forth.

2. The combination of a movable endless belt blackboard or blackboard-surface and an automatically-rotating wiper, for the purpose herein specified.

` 3. Amovable blackboard and a wiper therefor located in a close chamber, the said chamber being provided with a covered dischargeopening for the accumulated chalk-dust.

4. The combination of a movable endless belt blackboard, a revolving wiper, a turning handle or crank for driving the said rollers, belt,and wiper located in an oblique position, and gearing connecting the said handle, wiper, and endless belt, substantially as herein specified.

5. The pivoted hook-bearings P P, in combination with the revolving wiper N and the revolving rollers E I, substantially as and for the purpose herein specified.

6. In combination with the endless belt blackboard and fixed back board, the lip or flange Q and spring-plate R, whereby the npper edge of the endless belt is held straight and in position, substantially as and for the purpose herein specified.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.



LoUrs FEEsER, Jr., S. G. L. ROBERTS.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3163943 *Aug 17, 1962Jan 5, 1965Bell John WMechanical blackboard eraser
US3284924 *Mar 8, 1965Nov 15, 1966Parmenter Morgan DTeaching aid
US5607312 *Jan 13, 1995Mar 4, 1997Zhou; Jie-ZhangWriting board with an automatic erase device
US8100697Mar 11, 2009Jan 24, 2012Zipboard, Inc.Portable retractable erasable writing surface
US20120183943 *Jan 23, 2012Jul 19, 2012Zipboard, Inc.Portable retractable erasable writing surface
Cooperative ClassificationB43L1/08