EMBROIDERING MACHINE 259 



pleasure, while the sides of course continue of the same length ; the sides b b' and 

 b b" are prolonged, the one to the point d, and the other to the point c, and these 

 points c and d are chosen under the condition that in one of the positions of the 

 parallelogram, the line c d which joins them passes through the point /; this con- 

 dition may be fulfilled in an infinite number of manners, since the position of the 

 parallelogram remaining the same, we see that if we wished to shift the point d fur- 

 ther from the point b', it would be sufficient to bring the point c near enough to b", 

 or vice versa ; but when we have once fixed upon the distance b' d, it is evident that 

 the distance b" c is its necessary consequence. Now the principle on which the 

 construction of the pantograph rests is this : it is sufficient that the three points d,f, 

 and c be in a straight line, in one only of the positions of the parallelogram, in order 

 that they shall remain always in a straight line in every position which can possibly 

 be given to it. 



We see in the figure that the side b c has a handle B" with which the workman puts 

 the machine in action. To obtain more precision and solidity in work, the sides of the 

 pantograph are joined, so that the middle of their thickness lies exactly in the vertical 

 plane of the piece of goods, and that the axes of the joints are truly perpendicular to 

 this plane, in which consequently all the displacements are effected. We arrive at this 

 result by making fast to the superior great cross-bar D" an elbow-piece d", having a 

 suitable projection, and to which is adapted in its turn the piece d', which receives in 

 a socket the extremity of the side b d ; this piece d'is made fast to d'' by a bolt, but it 

 carries an oblong hole, and before screwing up the nut, we make the piece advance or 

 recede, till the fulcrum point comes exactly into the plane of the web. This condition 

 being fulfilled, we have merely to attach the frame to the angle/ of the parallelogram, 

 which is done by means of the piece F". 



It is now obvious that if the embroiderer takes the handle B" in his hand and makes 

 the pantograph move in any direction whatever, the point / will describe a figure 

 similar to the figure described by the point c, and six times smaller, but the point / 

 cannot move without the frame, and whatever is upon it, moving also. Thus in the 

 movement of the pantograph, every point of the web describes a figure equal to that 

 described by the point/, and consequently similar to that described by the point c, but 

 six times smaller; the embroidered object being produced upon the cloth in the position 

 of that of the pattern. It is sufficient therefore to give the embroidering operative who 

 holds the handle B" a design six times greater than that to be executed by the machine, 

 and to afford him at the same time a sure and easy means of tracing over with the 

 point c, all the outlines of the pattern. For this purpose he adapts to c, perpendicularly 

 to the plane of the parallelogram, a small style terminated by a point c', and he fixes 

 the pattern upon a vertical tablet K, parallel to the plane of the stuff and the parallelo- 

 gram, and distant from it only by the length of the style c d' ; this tablet is carried by 

 the iron rod e r , which is secured to a cast-iron foot E', serving also for other purposes, 

 as we shall presently see. The frame, loaded with its beams and its cloth, forms a 

 pretty heavy mass, and as it must not swerve from its plane, it needs to be lightened, 

 in order that the operative may cause the point of the pantograph to pass along the 

 tablet without straining or uncertainty in its movements. M. Heilmann has accom- 

 plished these objects in the following way. A cord e attached to the side b c of the 

 pantograph passes over a return pulley, and carries at its extremity a weight which 

 may be graduated at pleasure ; this weight equipoises the pantograph, and tends 

 slightly to raise the frame. The lower side of the frame carries two rods H and H, 

 each attached by two arms h h, a little bent to the left ; both of these are engaged in 

 the grooves of a pulley. Through this mechanism a pressure can be exercised upon 

 the frame from below upwards which may be regulated at pleasure, and without pre- 

 venting the frame from moving in all directions, it hinders it from deviating from the 

 primitive plane to which the pantograph was adjusted. The length of the rods H 

 ought to be equal to the amount of the lateral movement of the frame. Two guides 

 i t, carried by two legs of cast iron, present vertical slits in which the lower part of the 

 frame F' is engaged. 



3. Disposition of the carriages. The two carriages, which are similar, are placed 

 the one to the right, and the other to the left of the frame. The carriage itself is 

 composed merely of a long hollow cylinder of cast iron L, carrying at either end 

 a system of two grooved castors or pulleys i/, which roll upon the horizontal rails 

 K ; the pulleys are mounted upon a forked piece I', with two ends to receive the 

 axes of the pulleys, and the piece I' is itself bolted to a projecting car I cast upon the 

 cylinder. 



This assemblage constitutes, properly speaking, the carriage, resting in a perfectly 

 stable equilibrium upon the rails K, upon which it may be most easily moved back- 

 wards and forwards, carrying its train of needles to be passed or drawn through tho 

 cloth. 



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