US1633629A - Drafting machine - Google Patents

Description

. l .June 28 927 A.1.0. FORTIN DRAFTING MACHINE Original Filed May 23, 1925 3 Sheets-Sheet 1 n@ QW. en oos /n ventor:

r lo sul une 28, 1927.

J. o. FoRTm l DRAWING MACHINE original Fileduay 2s, 1925 s shuts-snm, 2

Fig. 9

by l l?" or ya.

June 28,1921. 1,633,629

- J.o. FoRTlN v DRAFTIN'Q maxima original Filed May 25, 192s s sheets-snm 3 Patented .lune 28, 1927.

JOSEPH' OVILA FORTIN, OTTAWA, ONTARIO, CAITADA..v

:DRAWING MACHINE.

Application ined Mayes, 1e25', serial No. 32,364, and in lGreat Britain This invention relates to drafting machines and more particularly to machines of the class comprising a plurality of connected parallelograms, one of which has a short link attached to the anchoring device and another has a short link carrying the drafting appliance, which is such as a pair of rules securedvat right angles, or a protractor. It is the chief object of the present invention to extend the range of usefulness'of such instruments,'to render them as light and as simple in construction as possible and to enable them to be folded into a small space for transport purposes.

The invention consists inthe arrangement and combination of parts `to be described hereinafter and more particularly pointed out in the appended claims.

Referring non7 to the accompanying drawings which illustrate by way of example certain convenient embodiments of the inven tion,

F 1 is a. plan, and Fig. 2 an elevation of the device'shown in Figure 1.

Fig. 3 isa plan of a slightly modied parallelogram. member.

. Fig. 4 isV a plan of a modied drafting memb er.

Fig. 5 is a section through the anchor member joint online 5-5 of Figure 1.

Fig. 6 is a section through the intermediate joint on line 66 of'Figure 1. f

Fig. 7 is a section through the drafting member joint .on line 7-7 of Figure 1.-

Fig. 8 is a view of the drafting member plate reversed.

Fig. 9 a plan of a form of plate showing the vernier scale. f

Fig. 10 is a plan with one rule and bracket separated, showingthe method of'securing the rule to the bracket. Y

Fig. 11 is a side elevation partially in section on line 11--11 of Figure 10. f Y

Fig. 12 is a section on the line XII--XII of Figure 3. e f

Fig. 13 is an enlarged view of part of Figure 12.

Referring first to Figures. 1- and 2, the

' main part of the machine consists oftwo jointed parallelogram shaped structures 1 and 2, (hereinafter referred to as parallelograms). The parallelogram 1 comprises a pair (of short links 3, 4 and a pair of long links 5. The `parallelogram 2 comprises similar pairs of links 6, 7 and 8. Owing tothe improved .Tune 24, 1924.. Renewed October 1926. L l f v method of support, these links are prefer'- abl'y made of -metal and nickel plated for finish and may be made considerably lighter than has hithertobeen possible. The paral-l lelogram 1 is securedvby means of the link 3 to the anchor plate 9, which may be made in the form of a bracket with screw holes 9a forA permanently attachingl it to the drawing board or drafting table. and-6 are secured together by a clamping screw 1 0 while the circular plate 11, carrying thel drafting attachment is similarly clamped to the link .7 by turning the head 12 of a screw. For cheapn'ess and simplicity all three clamps have their -main partsmade of the same` construction. Figures 5, 6`and 7 .sh-ow sections through the joints.

' ln Figure 5 the anchor plate carries a hollow truncated conical or male member, which is engaged by a hollou7 truncated conical or female member' 14. rllhese are drawn together by a clamping screw 15 which forms an extension of .a pillar 16, Ato be referred to later. The shank end of the screw 15 makes a good lit through plane holes in the link 3', and the clamp member 14. By loosening the clamping screw 15, the link 3 may be adjusted-easily-into any required angular position, relative to the anchor plate 9.l

Similarly inA YFigure 6V the intermediate joint comprises a male member 17 carried on link 6, a female member 18, carried on link 4,

and a clamping screw 19, formed with a large head 10; while the drafting joint, Fig. 7,.comprises a male member 2O carried by the circular plate 11a female member 21, carried vby the link 7, and a clamping screw 22, Vover which lits an internally threaded tubular nut 23, having an enlargedhead, 12.

In .each case by this method of construction, the clamping members are of such a size that the top surface of the male member does 'not reachthe inner flat surface of the hollow together at each of the three joints are thus easily angularly adjustable relatively to each other,vand turn truly about the centre point. Referring now particularlyto Figures f1,

The links 4v 7, 10gand 11, the drafting appliancecomprisesa supporting plate 2 5, having the bracket yarms 26 rigidly` secured to it by ,meansY .of a.' bar 27. The graduated circular plate 1l, )feviouslv referred to, may rotate on the supporting plate 25, or may be clamped thereto by means of a clamping screw 28. The bar 27 also carries a segment 29, which may bear a Zero mark, as shown in Figure l, or may have a Vernier scale as shown in Figure 9. ln order to iX the Zero mark accurately' at certain common anofles, for example 300, 45O and 600, holes 30 Hsee Fig. 8.) are made in the supporting plate 25. In addition to the examples given abo-Ve a hole is made (though it is notshown in the drawings) at OO. rlhe graduated plate 1l carries a plunger 3l (see Fig. 7) fitting the holes accurately, which is normally mai`ntained out otl contact with the supporting plate 25 by a `spring 32 inside a cap 83. When it is desired to draw lines at say 30 to the zero line, the supporting plate 25 is rotated relatively to the plate 11, and simultaneously the cap '33 is pressed downwards. When the bracket is at 30o to its initial'position, the plunger will sink into the hole 30,

Vwhen the screw 28 may be vclamped and apparatus lined. j

It is found with some sizes ot machines that it the circular plate 1l has its pivot eX- actly 'halt way along the link 7, this link and the rods 8 -are apt to obscure the scale. In order to avoid this it is preferable to secure the clamp nearer to one end of the link 7 than the other, asis shown in Figure l,

rlhe means for supporting the intermedi.- ate joint and tor preventing it 'from sagging when it -is oit` the board, are shown in Figures 2, 5 and 6, and comprisethe pillar 16, and a thin circular tie rod 34. The lower end ot this tie rod is formed with. a ring 35, which en'gagge's with the reduced or neck portion of an upstanding stud on the top 'of the clamp V19 at the intermediate joint. The tie rod 34 is made slightly longer than is necessary and thefup'per .endy is 'screwthreaded An inverted cup'SG, which engages the head ot' the pillar 16, tits over this screw-'threaded portion and is'held in position between two nuts, 37; by-adjusting these, the intermediate joint can'be held at any desired distance above the drawing paper.

In order to prevent the tie rod 34 pulling some oit thejoi'nts between the links apart, these latterare formed by means ot upstanding `pins B8 (Figure which tit accurately within holes in the members with which they make joint. rlhese pins have upper reduced ends, and Yare furnished with milled nuts 39 to prevent the joints coming apart.

Referring now to Figs. l() and ll the supporting bracket for the rules is formed with a pair of arms 26,"extendingiat right angles.

These are designed to llit over the rules 4() which are provided with metal plates 41, having two Ahemispherical projections or studs 42, 43. These studs tit into corresponding ' depressions 44, 45 in the bracket arms.

This connection ensures accurate location of the.' rule by means ot' the stud 42 and hole 44 and allows, by means ot the groove 45t`or slight variations Ain distancebetween the studs 42 and 43. The rules and bracket arms are drawn together and clamped by means ot screws 4G passing tlnough'holes 47 in the bracket arms 'and screwing into tapped holes in the plates on the' rules.

In order to' avoid distortion or' the rules during clamping, the depression 44 is made slightly'less than a hemisphere and the depression y45 is slightly'lessthan a semicircle in cross sectionthroughoutits length. This allows ot a` slight rockin'gotthe rule relative Atothe plate and as'the holes 47 in the` bracket arm are made larger than is necessary, the rule can be clamped either `parallel with the bracket arm or elseinclined at a small angle thereto. rlhis allows the rules always to be set in the same plane as the surface ot the drafting table. rIlhe meta-l plates 4l are'secured to the rules '40 inthe following way: At one end `Ot each plate there is'a screw 42 passing into the wood ot the rule. The head of this lscrew forms one of the hen'ii'spherical studs; at the other end a second screw 49 passing through a slot 5U cut in the lplate 4l, which screw and slot lie beyond the bracket arm 26. By loosening the screw 49, slight angular adjustment ot the rule relative to theplate can be mad-e, the screw 42 acting as a hinge. The second hemispherical stud 43 has a shank which does not Ipassiinto the'wood and therefore does not interfere with this adjustment. Both the rules 40 are provided with two metal plates 4l, one at each end, so that the rulesl are'reversible. This is 'of great convenience as a metric scale can' be used 'on one edge, andl an inch'sc'ale on the other. With the construction described therev is no difficulty in reversing the rules, all that is needed being to loosen the screws Rules secured in this way are. accuratelylocated, and there are no large projecting parts to interfere with the drattsmans work.

Although one particular machine has been described, considerable variations may be made 'without departing from the scope of the invention. F or example, the metal bracket arms 26 may be formed as partial tubes, each having a section slightly less than a semi-circle, instead ot having two hemispherical depressions to receive the studs ontheplates. Again, only one screw A46 maybe used to'clamp the rule to the bracket.

In yet" another variation, the means for eiigagmg' the tie rod withA intermediate oint may comprise, 1nv place of the ring 35,'an in- Airai those already described.

verted cup engaging with a correspondingly shaped undercut recess in the clamp.

In 'Figure 4 the drafting vmember comprises a substantiallyl U-shaped plate 67 which is pivoted to the short link 7 and can be clamped thereto by means' of apair of coacting cone members21 and 68 similar to One limb of the plate 67 has a rule detachably connected directly to it and the other limbhas pivoted to it at 71 a graduated sector 70 which detachably carries a rule and may be clamped in adjusted position by means of aclamping screw 7 3 which is arranged to press a small plate 74 into frictional engagement with a flange on the plate 7 O'.

Figures 3 and l2 are respectively plan and partial section of an attachment sultable for use by a surveyor. In this form a plate 53 is pivot-ally attached to link 7 by means of co-acting cone members 51 and 5l which 'may beclamped by a screw 52, the plate 53 being secured to cone 51 by screws 54. The plate 53 is approximately triangular and a graduated ring 55 is attached to it by means of screws 56. The ring 55 is supported in horizontal position as by means of feet 57. A flange on an annular graduated plate 58 lies in a recess in the inside of plate 55 and may be clamped to plate 55 by means of a nut and bolt 60, the bolt having a flange engaging the underside of ring 55 and keyed to ring 58 by a pin 62. rl`wo elbows 63 are -carried by the ring 5S and a graduated rule 64 is attached to the elbows by means of screws 65, engaging slots in the brackets which permits adjustment of the rule. i

lt will be'understood that various changes may be made in the details of the construction and in the drafting attachments without depating from the scope of the invention as defined in the appended claims. For example, any number of parallelogram structures may be connected together as may be necessary to move the drafting attachment to the position where the drawing work is to be done.A

What I claim is:

l. A drafting machine comprising, in combination, a pair of pivotally connected parallelogram-shaped structures each consisting of a pair of parallel short links pivotally connected by a pair of parallel longer links, an anchoring device pivoted to the short link at one end of the machine, and a drafting member carried by the short link at the other end of the machine, said drafting member comprising a pair of rules, a

bar pivoted to the last mentioned short link and carrying one of the rules and a graduated member pivoted on the bar and carrying the other rule.

2. A drafting machine comprising, in combination, a pair of pivotally connected parallelogram-shaped structures each consisting of a pair of parallel short links pivk otally connected by a pair of parallel longer links, an r anchoring device pivoted to the short link at one endv of the machine and a drafting member carried by the short link at the other end of the machine, said draft- `ing member comprising ,a bar pivoted vto the vlast mentioned short link and having two yarms, a rulezA detachably'carried by one of the arms, a graduated member pivoted to theother of the arms and detachably carrysubstantially hemispherical studs adapted to lit into'corresponding holes in the said arm andmeniber respectively, to which they are attached, and screws for clamping said rules in adjusted position, Y

4. A drafting machine, as defined in claim 2, whereinthe rules are provided with plates for the purpose of securing them to the arm and graduated member, saidplates having substantially hemispherical studs adapted to fit into corresponding holes in the said arm and member respectively, to which they are attached, and screws for clamping saidrules in adjusted position, said holes being formed substantially as a hemispherical recess and as a groove of semi-circular cross section respectively, so that accurate fitting may be obtained even when the distance between the studs varies, substantially as described.

5. A drafting machine, as defined in claim 2, wherein the rules are provided with plates for the purpose of securing them to the arm and graduated member, said plates having' substantially hemispherical studs adapted to fit into corresponding holes in the said members, .to which they are attached, and screws for clamping said rules in adjusted position, said holes being formed substantially as a hemispherical recess and as a groove of semi-circular cross section respectively, so thataccurate fitting may be obtained even when the distance between the studs varies, wherein provision is made for rocking the rules relative to their respective carrying members by making the said holes in the latter slightly less than hemispheres or than half cylinders, respectively, and by making holes which receive the screws in the said carrying members of greater diameter than the said screws, as herein described.

6. A drafting machine, as defined in claim 2, wherein the rules are provided with plates for the purpose of securing them to the arm and graduated member, said plates having substantially hemispherlcal studs adapted to ico lit into corresponding holes in the said niemhers, to which they are attached, and screws for clamping said rules in adjusted position, and wherein each rule has two similar plates, one at each end, and is thereby niade reversible.

7. A drafting machine, as defined in claini l, having a graduated disc on said bar and capable olf rotation with respect thereto, an

10 index device coacting with the graduations on the dise and carried `by the bar, means for clamping the disc to the link, means for clamping the bar to the disc, a` plunger carried by thediso and a plate between Ysaid disc andhar, fixed to the har and having a hole adapted to be engaged by said plunger when the .latter is depressed.

In testimony whereofl I afiX my signature.

JosnPH oViLA ronrn

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