US3543282A - Drawing board - Google Patents

Description

NOW 1970 L. E. F. SAUTEREAU 3,543,282

DRAWING BOARD Filed April 4, 1968 4 Sheets-Sheet l Nov. 24, 1970 SAUTEREAU 3,543,282

DRAWING BOARD 4 Sheets-Sheet 2 Filed April 4, 1968 L. E. F. SAUTEREAU DRAWING BOARD Nov. 24, 1970 Filed April 4, 1968 4 Sheets-Sheet 5 L. E. 4F. SAUTEREAU 3,543,282

Nov. 24, 1970 DRAWING BOARD 4 Sheets-Sheet 4 Filed April 4, 1968 United States Patent 3,543,282 DRAWING BOARD Lucien Emile Frangois Sautereau, 16 Avenue Montaigne, Paris, France Filed Apr. 4, 1968, Ser. No. 718,726 Claims priority, application France, Apr. 11, 1967, 102,323 Int. Cl. A47b 27/18 U.S. Cl. 108144 4 Claims ABSTRACT OF THE DISCLOSURE A- drawing board with adjustment in height, orientation, inclination and lateral translation, comprising a vertical body of rectangular section open on one side so as to form a U, and a pillar sliding in said body and having a closed section forming an irregular octagon or a rectangle with chamfered corners, each chamfer being arranged to roll on a pair of vertically-displaced rollers mounted in the bisecting line of each angle of the rectangular body, play between the body and puller being cleminated by nonelastic screw means eifecting a slight deformation of the arms of the U-section.

The present invention relates to a drawing board, pro vided, separately or in any combination, with a plurality of improved devices which render it adjustable in height, in inclination, in orientation and in lateral translation with respect to its base. More precisely, the invention has for its object a drawing board provided with adjustments in height, in orientation and in inclination, which do not introduce any play or any elasticity in spite of variations of weight which the draughtsman appiles to the table during his work, to which such play and elasticity would be prejudicial. In particular, the invention has for its object an adjustment in height or vertical sliding movement, without any play and without any elasticity.

Briefly, the vertical sliding movement of the drawing board according to the invention is obtained by means of a body and a pillar arranged to slide one in the other, one of these two members having a closed profile and the other having an open profile substantially parallel to that preceding, these two profiles surrounding each other, while the exact elimination of play is obtained without elasticity by a slight deformation of the open profile actuated by non-elastic means.

The said profiles are preferably sufliciently dilferent from a circle or from a rounded curve to prevent the possibility of any undesired rotation of the pillar in the body, and on the contrary in order to position it in rotation without play or elasticity.

According to a preferred form of embodiment of the invention, the vertical sliding device comprises a ver tical body of U-section rigidly fixed to the base and provided with a device for regulating the distance apart of the arms of the U, and a pillar having the section of an irregular octagon (a rectangle with chamfered corners), sliding vertically in the body, each chamfer r011- ing on a pair of rollers mounted on a bisecting line of an angle of the body.

It will be observed that the said device for adjusting the distance apart of the arms of the U permits the rolling movement of the chamfers on the rollers to be precisely regulated without play, that is to say regulates the vertical sliding movement of the pillar in the body Without introducing any elasticity.

Briefly, the device for regulating the height according to the invention comprises means for locking the said sliding movement, constituted by a plate coated for ex- 3,543,282 Patented Nov. 24, 1970 ice ample with rubber, sliding on studs in the body, applied by a spring against one side of the pillar, and by a re.- leasing pedal which moves said plate away from the pillar against the action of the said spring.

The device for regulating the height according to the invention further comprises a balancing of the moving portion (pillar, drawing board proper and associated members), comprising a spring, for example pneumatic, actuating vertically a pulley over which passes a cable going from the base of the body to the base of the pillar.

According to the invention, this pulley is double, namely a pulley on which is wound a cable going to the base of the body and a cam pulley with a variable profile, on which is wound a cable going to the base of th pillar. It will be observed that the variable profile of the cam pulley makes it possible to compensate for the variation of the force supplied by the pneumatic spring during the course of its operation. It will further be noted that, in order to balance moving systems of different weights, it is only necessary to change the diameter of the ordinary pulley, the same pneumatic spring and the same cam pulley being siutable for all moving svstems.

The device for adjusting the orientation according to the invention briefly comprises, at the top of the pillar, a vertical trunnion, on which is pivoted a yoke rigidly fixed to the drawing board, provided with a friction system and locking by screw, bringing together two parts tangential to the trunnion.

The device for regulating the inclination according to the invention briefly comprises, at the top of the said yoke, a horizontal shaft on which is pivoted the drawing board proper, and a system with balancing by spring and locking by coaxial screw.

The lateral translation device according to the invention comprises, between the said inclination-regulating device and the drawing board, two transverse parallel rails rigidly fixed to the board and permitting its sliding movement.

One preferred form of embodiment of the invention, relating to a drawing board provided with all the improved devices according to the invention, will now be described with reference to the accompanying drawings, given by way of non-limitative examples, in which:

FIG. 1 is a general side elevation with parts broken away;

FIG. 2 is a general vertical cross-section, taken along the broken line II-II of FIG. 1;

FIG. 3 is a horizontal section taken along the broken line III-III of FIG. 2;

PG. 4 is an explanatory detail on a larger scale of the central portion of FIG. 3, showing the device for sliding in height;

FIG. 5 is a side elevation, similar to FIG. 1, showing diagrammatically the balancing of the moving portion;

FIG. 6 is a side view and FIG. 7 is an axial section of a vertical balancing cam-pulley;

FIG. 8 is a detail in cross-section taken along the line VIII-VIII of FIG. 2, showing the orientation locking device.

This preferred construtcion of the drawing board according to the invention (see FGS. 1 and 2) rests on the ground by means of a base 1 with an adjustable foot 2, comprising a vertical body 3. The horizontal section of this body (FIG. 3 and the detail shown in FIG. 4) is generally rectangular with rounded corners, but one of the large sides of the rectangle is open, and is only closed by a thin plate 4. The structural section has thus the shape of a U, in which the distance apart of the legs can be regulated by one or several pairs of threaded hori zontal rods 5 placed behind the plate 4 and joined together in pairs by a diflerential nut 6. In the legs of the U are fixed, at two different levels, two pairs of yokes 7 each supporting a pair of rollers 8 on ball bearings, mounted in the bisecting planes of the angles of the body 3.

In the body 3, there is adapted to slide vertically a pillar 11, the section of Which is an irregular octagon, that is to say a rectangle, parallel to the rectangle of the body 3, but in which the corners have been rounded-off by the chamfers 12, which roll on the rollers 8. One pair of rods is preferably placed at the same height, or at least close to it, of each set of rollers 8. The said chamfers 12 may be fiat but they are preferably rounded as shown, and the rollers 8 have a concave profile with a curvature slightly smaller.

There is thus obtained a bearing surface for the pillar along four vertical generator lines which are clearly defined from the geometrical point of view. In consequence, by adjustment of the rod 5, there is obtained a vertical sliding movement with out any play and without any elasticity, and positioning in rotation is also obtianed without any play and without elasticity.

The locking of the vertical sliding movement of the pillar 11 in the body 3 is obtained by the application against a large face of the pillar 11 of a plate 21 provided with an adherent sheet 22, for example of rubber and sliding on studs 23 on the body 3' by the action of a pushrod 24 actuated by a screw 25 controlled in rotation by a toothed wheel 26, a chain 27 and a tension spring 28 fixed at 29 to the body 3, as shown in FIG. 2. The position of the pushrod 24 and the screw 25 is of course adjustable by means of a nut 30 (see FIG. 4). Release is obtained by depressing a pedal 32 mounted on the base 1, the arm 33 of which acts through a cable 34 on the chain 27 in opposition to the spring 28. This pedal 32 may be fixed in the released position by the co-operation of the arm 33 with a pawl 35 (FIG. 1).

The balancing of the vertical sliding movement comprises a pneumatic spring (see FIG. 5), the cylinder 41 of which is mounted on the base 1, and in which the piston rod 42 carries a horizontal shaft 43. It is known that a pneumatic spring of this kind supplies a force which decreases with its elongation, and the invention provides a compensation for this decrease. Preferably, but not necessarily, the shaft 43 carries two keyed pulleys 44 and 45; on the pulley 44 is attached and wound a cable 46 fixed at 47 to the foot of the clylinder 41. On the pulley 45 is attached and wound a cable 48 fixed at 49 to the foot of the pillar 11. The pulley 44 is cylindrical but the pulley 45 has a variable profile, thus producing the desired compensation.

If it is desired to balance the system by means of a symmetrical arrangement, the pulley 45 may be placed between two pulleys 44, each provided with a cable 46. Another arrangement of these members is shown in FIGS. 1 and 2. The cylinder is fixed inside and at the top of the pillar 11 and ts rod 42 carries at its lower extremity a triple pulley 51 (see FIGS. 6 and 7). This pulley 51 is provided with two circular symmetrical grooves 52, in each of which is attached and wound a cable 53 coming from a fixed point 54 of the body 3 (see FIG. 2), and with a groove 55 having a variable radius, in which is attached and wound a cable 56 coming from a fixed point 57 of the pillar 11, as shown in FIG. 2.

For the orientation of the drawing board, the pillar 11 is provided at its upper portion (see FIG. 2) with a vertical trunnion 61 keyed at 6 2 in a bush 63. On the trunnion 61 is pivoted a yoke or cap 64 which is bored slightly oversize as shown in FIG. 8. The orientation locking lever 65 actuates a screw 66 which grips tangentially on the trunnion 61 by a nut 67 with a counter support 68.

For the inclination of the drawing board, the cap 64 is provided at its upper portion (see FIG. 2) with two bearings 71 and 72, in which rotates a horizontal shaft 73, keyed at 74 in a slide 75. The inclination locking 4 lever 76 actuates a screw 77, coaxial with the shaft 73 and clamping against the side of the cap '64 an end-plate 78 provided with a friction lining 79. A coaxial spring 81 at the other extremity of the shaft 73 ensures the balance in inclination of the drawing board.

The lower part of the structure of the drawing board proper comprises two rails 83 (see FIGS. 1 and 2), mounted transversely and fixed to two vertical metallic members 84 mounted under the drawing board 85, the sliding of the rails 83 on the slide 75 permitting the lateral translation movement of the board.

What I claim is:

1. A drawing board with adjustment in height comprising two members constituted as a vertical body and a pillar adapted to slide in said body, one of these two members having a closed section and the other an open section substantially parallel to the first, said sections being adapted one to enclose the other, non-elastic means for producing a slight deformation of said open section to eliminate play between said sections, a balancing device for the vertical sliding movement of the pillar including a pneumatic spring which comprises a jack, a rod for said jack, a pulley mounted on said rod on an extremity there' of, a cable attached and wound on said pulley, a cam pulley with a variable profile mounted on the extremity of said rod and fast with said first pulley, and a second cable attached and wound on said cam pulley, one of said cables having a free extremity attached to the body, the other cable having a free extremity attached to said pillar.

2. A drawing board as claimed in claim 1, in which said open section is that of said body and is of rectangular shape openon one side so as to form a U, said non-elastic means regulating the distance apart of the arms of said U, said body further comprising a pair of rollers mounted along each bisecting line of an angle of said rectangle, said closed section being that of said pillar and forming an irregular polygon with chamfered corners, each chamfer rolling on one pair of said rollers.

3. A drawing board as claimed in claim 2, in which each said chamfer is of rounded convex form and each said roller has a concave rounded profile having a curvature slightly less than the curvature of said chamfer.

4. A drawing board with adjustments in height, in orientation, in inclination and in lateral translation with respect to its base, and comprising a vertical body of rectangular section open on one side, threaded rods with differential nuts adapted to regulate the opening of said rectangular section, at two different levels, a set of four rollers mounted along the bisecting lines of the angles of said rectangle, a pillar of polygonal section with chamfered corners, the chamfers being convex and the associated rollers concave with a curvature slightly less than that of said chamfers, said pillar being slidably movable in said vertical body by rolling of the chamfers on the rollers, means for locking the vertical sliding movement comprising, opposite one face of said pillar, a plate lined' with a sheet of rubber and a pedal returned to the locking position by a spring with a holding pawl and adapted to actuate said plate, means for balancing said vertical sliding movement comprising a pneumatic jack mounted inside said pillar, a rod for said jack, a triple pulley mounted at the extremity of said rod and having two circular grooves and a groove of varying radius, in each circular groove, a cable attached and wound on said pulley and connected to the body, in said groove of varying radius, a cable attached and wound on the pulley and connected to said pillar, an orientation device comprising at the top of said pillar, a vertical trunnion and a cap adapted to be locked by two tangential locking parts, a screw for bringing said two parts closer together and a lever for actuating said screw, an inclination device comprising two trunnions on said cap, a shaft in said trunnions, a friction lining, a screw applying said lining against said cap and a lever actuating said screw, a bal- 5 6 ancing device comprising a coaxial spring, a lateral trans- 3,194,187 7/ 1965 Linder, et. a1. 108146 lation device comprising two transverse rails rigidly fixed 3,285,207 11/1966 Hagen 108-144 to two metal members secured under said drawing-board, 3,358,620 12/ 1967 Parigi 1086 and between said two rails, a slide fast with the shaft of 3,380,405 4/1968 Brecki 108--136 said inclination device. 5

BOBBY R. GAY, Primary Examiner References c'ted GLENN o. FINCH, Assistant Examiner UNITED STATES PATENTS 744,613 11/1903 Reimold 108-144 XR U.S. C1.X.R. 2,469,896 5/1949 Schaef ..108-148 10 108-6, 141

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