Improvements in the Mounting and Equipment of Continuous Draw- ing or Writing Surfaces, or other Forms of " Black-boards."
Year: 1896

page_text: Date of Application, 10th Dec., 1896
Complete Specification Left, 10th Sept., 1897-Accepted, 4th Dec., 1897
PROVISIONAL DIT
Improvements in the Mounting and Equipment of Continuous Draw-
ing or Writing Surfaces, or other Forms of " Black-boards."
We, JOHN CHARLES TARVER, M.A., Head Master of the School of The Red
House, and ARTHUR HAWARD, Cabinet Maker and Upholsterer, of Northgate, both
of Darlington, in the County of Durham, do hereby declare the nature of said
invention to be as follows:-
Our invention relates specially to those forms of "black-boards" for educational
purposes, in which a continuous sheet is mounted upon rollers so that any part
may be brought into position for drawing or writing upon, and to the equipment
of such continuous "black-boards," or of any other forms of "black-boards," with
appliances which will enable diagrams, geographical, or geometrical figures to
be drawn to scale; to enable them to be reproduced upon an enlarged scale upon
the "black-board" from a smaller diagram attached to the frame-work by means
of a "pentagraph" and to afford facilities for suspending maps or charts on one
or both sides of the "black-board" to which reference can be made whilst the
lecturer or demonstrator still requires to refer to, or use, the continuous drawing
or writing surface or the "black-board."
The mounting of a continuous sheet drawing or writing surface, may be in
a frame supported like an easel by rests at the back, or on a movable platform or,
it may be, attached to a wall. The front portion of this frame is formed of two
pairs of parallel struts one pair being at each end of the rollers round which the
continuous sheet moves, the bearings of which rollers are supported in blocks
which fit into guides formed in the struts and the bearings of the lower roller
are fitted with screws or equivalent means for adjusting the tension of the sheet,
at each side independently. The struts are stiffened or braced together at
suitable intervals by lattice work which gives them both rigidity and lightness
of appearance.
The front pair of struts project at each end forward from the drawing or writing
surface of the sheet and are parallel to its surface and a scale of linear measures
is marked upon or affixed to the front edge of one or both struts, to mark parallel
horizontal lines, spaced as required, by means of a parallel ruler extending across
the sheet movable upward or downward, always in parallel lines, by means of
link work, or equivalent parallel action, below and having its ends guided in
grooves in the front pair of struts and furnished at one or both sides with a catch
working on the edge of each or either strut fixing it in position at any desired
height. Alongside of this ruler and parallel to it is a bar having a groove along
its length and sliding in this groove is a pivoted arm, which may be turned to
any angle to 90° one side or other of the vertical (above or below the grooved
bar) which angle is indicated upon a protractor which slides with it in the groove
or the pivoted arm may in some cases be applied directly to the frame instead of
to the ruler. This pivoted arm is slotted along its length and carries a cross arm
(which may also be slotted) sliding in said slot and turning on a pivot so that

page_text: it may be used to extend the length of the slotted arm or, by adjustment by a set
screw, its ends may describe various radii, as compasses, and may be fixed at any
angle to the slotted arm to which may be fitted a protractor to indicate such angles.
Both the ruler and the pivoted arms will also be marked to linear scale on their
front edge or edges. The whole of these appliances fold over each other and may
may be enclosed when not in use, within a flap and locked therein, and this flap may
be turned upward upon hinges supported by brackets or stays to form a flat shelf
upon which models may stand for teaching solid geometry, or such a shelf may
be provided upon the front of the parallel ruler.
A smaller drawing board may also be attached to either side of the main frame,
upon which board diagrams may be fixed to be enlarged on the continuous surface
or "black-board" by means of a "pentagraph." In order to enable maps, charts,
or the like, to be shewn for reference at one or both sides of the continuous surface
or "black-board" a movable rod is so arranged that it can be extended at either
side to attach the map and supported by a light stay from the frame.
Dated this 10th day of December 1896.
Improvements in the Mounting and Equipment of Continuous Draw-
ing or Writing Surfaces, or other Forms of "Black-boards."
We, JOHN CILARLES TARVER, M.A. Head Master of the School of The Red
House, and ARTHUR HAWARD, Cabinet Maker and Upholsterer of Northgate, both
of Darlington in the County of Durham, do hereby declare the nature of said
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement.
Our invention relates specially to those forms of."black-boards" for educational
purposes described in Tarver's Patent No. 21,993 dated Oct. 5, 1896 to which we
beg leave to refer in which a continuous sheet is mounted upon rollers so that
any part may be brought into position for drawing or writing upon, and further
to the equipment of such continuous "black-boards," or of any other forms of
"black-boards," with appliances which will enable diagrams, geographical or
geometrical figures to be drawn to scale, to enable them to be reproduced upon
an enlarged scale upon the "black-board" from a smaller diagram attached to
the framework by means of a "pentagraph" and to afford facilities for suspend-
ing maps or charts on one or hoth sides of the black-board" to which reference
can be made whilst the lecturer or demonstrator still requires to refer to, or use,
the continuous drawing or writing surface or the "black-board."
The mounting of a continuous sheet, drawing or writing surface may be in
a frame supported like an easel by rests at the back, or on a movable platform or,
it may be, attached to a wall. The front portion of this frame is formed of two
pairs of parallel struts one pair being at each end of the rollers round which the
continuous sheet moves, the bearings of which rollers are supported in blocks
which fit into guides formed in the struts and the bearings of the lower roller
are fitted with screws or equivalent means for adjusting the tension of the sheet,
at each side independently. The struts may be stiffened or braced together at
suitable intervals by lattice work which gives them both rigidity and lightness
of appearance.

page_text: The front pair of siruts project at each end forward from the drawing or writing
surface of the sheet and are parallel to its surface and a scale of linear measures
is marked upon or affixed to the front edge of one or both struts to space parallel
horizontal lines, spaced as required, by means of a parallel ruler extending across
the sheet movable upward or downward, always in parallel lines, by means of
link work, or equivalent parallel action, below and having its ends guided in
grooves in the front pair of struts, and furnished at one or both sides with a catch
working on the edge of each or either strut, fixing it in position at any desired
height. Alongside of this ruler and parallel to it is a bar having a groove along
its length and sliding in this groove is a pivoted arm, which may be turned to
any angle to 90° one side or other of the vertical, which angle is indicated upon
a protractor which slides with it in the groove or the pivoted arm may in some
cases be applied directly to the frame instead of to the ruler. This pivoted arm
is slotted along its length and carries a cross arm (which may also be slotted)
sliding in said slot and turning on a pivot so that it may be used to extend the
length of the slotted arm or by adjustment by a set screw its ends may describe
various radii, as compasses, and may be fixed at any angle to the slotted arm
to which may he fitted a protractor to indicate such angles. Both the ruler and
the pivoted arms will also be marked to linear scale, on their front edge or edges.
The whole of these appliances fold over each other and may be enclosed, when
not in use, within a flap and locked therein and this flap may be turned upward
upon hinges supported by brackets or stays to form a flat shelf upon which models
may stand for teaching solid geometry or such a shelf may be provided upon
the front of the parallel ruler.
A smaller drawing board may also be attached to either side of the main frame,
upon which board diagrams may be fixed to he enlarged on the continuous surface
or "black-board" by means of a "pentagraph." In order to enable maps, charts,
or the like, to be shewn for reference at one or both sides of the continuous surface
or "black-board" a movable rod is so arranged that it can be extended at either
side to attach the map and supported by a light stay from the frame.
DESCRIPTION OF DRAWINGS.
On the accompanying sheet we illustrate our invention in one form in which
we propose to carry it into practical application. Fig. 1 representing a perspec-
tive elevation of a continuous writing surface mounted and partially equipped,
Fig. 2 shewing a partial elevation with a shelf for models in teaching solid
geometry, and Figs. 3, 3 an apparatus fitted with a slotted pivoted arm and
cross arm pivoted thereto for producing angles describing circles or ellipses or
like figures. The same letters indicate the same or equivalent parts on all the
Figs.
A A'. are the parallel struts forming the main frame, like an easel, inserted in
the base B and supported by back stays C. At top the struts A A. unite and
form a cleft to receive the bearing 1) which carries the upper roller E the lower
roller E. being fitted in adjustable bearings as described in Patent No. 21,993
and being revolved so as to move the flexible sheet F upward or downward by a
crank handle G, Lattice work, not shewn, may be inserted between the struts A 'A'.
which will enable them to be made lighter-The front pair of struts A at each
side of the surface F project forward from said surface parallel with it and either,
or both, has a vertical scale of linear measures H marked upon or attached to the front
edge to space parallel horizontal lines across the sheet by means of the parallel
ruler J which is movable upward or downward in parallel lines by link work K
sliding in a groove in the lower rail L and a corresponding one in the parallel
ruler J. The ends of the ruler are guided in grooves in the front pair of struts A A
and it may be fitted at one or both ends with a catch to retain it at any desired
height. Along the length of the lower rail L is a groove provided with a slide
movable to right or left into which is centred the pivoted arm M which may be
turned to any angle (to 90°) with the vertical, on one side or other indicated upon
a protractor N sliding with it in the groove in the lower rail L in which groove

page_text: it can be fixed by a jam screw at any angle, The arm M may be slotted along
its length and carries a cross arm 0 which may also be slotted and by the adjust-
ment of a fixing screw P may be fixed at any angle to the arm M. Both the
parallel ruler J and the arm M may be marked with a linear scale on their edge
or edges. The pivoted arm M with cross arm 0 the protractor N may be attached
to a groove in the parallel ruler J if desired so as to rise and fall with the parallel
ruler. The whole of these appliances viz: the parallel ruler J the link work K
the slotted arm M and the cross arm O with the protractor may be covered up
when not in use by a hinged flap which may when turned up form a shelf to
carry models when teaching solid geometry. A box Q may be formed below the
lower rail L for the safe keeping of instruments crayons or like articles in which
they may be locked. The slotted arm M and the cross.arm O with the protractor
will preferably be detachable from the lower rail L or the parallel ruler J so
that, when not in use, they may be removed. Maps, charts or other diagrams
may be exhibited for reference by means of a folding bracket R supported, at one
or both sides of the frame by a diagonal stay to which bracket the map may be
suspended by a clip S. The maps when not in use may be rolled and stored at
the back of the frame supported by a cross rail provided for the purpose at the
back of the frame and resting in a shelf W in the base. The book rest T may
be fastened to either side of the frame and at a convenient height and a spring
"clip" is provided to hold the book and keep the place or, when required, the
book rest may be used for exhibiting diagrams and may also be attached to
the parallel ruler so as to form a shelf for exhibiting models when it is not required
as a book rest.
A pentagraph may be attached to either side of the frame to produce upon the
writing surface an enlarged copy of a drawing or diagram fixed on a drawing
board but it has not been thought necessary to illustrate this as it will be readily
understood and only forms a part of our invention in combination with other
portions of the equipment. When the apparatus is to be suspended from or fixed
against a wall the frame will preferably be constructed so as to slope the writing
surface outward at bottom and for lightness lattice work will carry the front
struts A and the base B and back stays C will be dispensed with.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is:-
1st. A continuous writing or drawing surface mounted on rollers in a frame so
constructed relatively to said surface as to provide for the equipment with a
parallel ruler to produce lines spaced according to a linear scale on the edge or
edges of the front struts of the frame, projecting beyond the surface of the con-
tinuous sheet.
2nd. The fitting to such a continuous writing or drawing surface of slotted
bars to produce primary angles indicated by a protractor or secondary angles
thereto or to describe circles, ellipses or the like, with provision for displaying
maps charts or diagrams and a book rest for ready reference of the lecturer or
demonstrator with a shelf for exhibiting models against the black surface.
3rd. The method of mounting and equipment of a continuous writing or draw-
ing surface comprising the various parts in combination for effecting the said
operations substantially as hereinbefore described and illustrated on the drawings
herewith or any mere modification of details to effect such operations.
Dated this 10th day of September 1897.
T. J. DANSON
Agent for Applicants
New Castle upon Tyne.