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* these operations should be performed by distinct machines, in order that the number of each kind in the factory may bear such proportion to the others as will keep them all constantly employed. The operations of cutting off and heading the blank should be performed by one machine, dressing or turning the head by another, nicking by a third, and cutting the thread by a fourth. Patents have been granted during the year for improvements in machinery for each of these operations. One patent has been granted for a machine for cutting off and heading the blank. This machine operates upon the same principle with rivet machines, and is capable of general application where similar operations are required. Heretofore, in machines of this character, each cutter has been combined with a separate header, the two operating alternately; the header, therefore, is in operation while the cutter is cutting and carrying the blank to it, and also while the cutter is going back for another cut. It is evident, therefore, that the header might perform double its usual duty. The inventor of the above-mentioned patented machine has so arranged the parts as to combine each header with two cutters, each operating upon a different rod or reel of wire, and each of which brings the blank it has cut to the header as the other cutter is withdrawn. Thus each cutter performs its usual duty without the loss of time, and the header performs double duty. It is evident that by this device each machine will produce nearly double the number of headed blanks that would be produced in the same time by the ordinary machine. There is some novelty in the mechanism by which the combination is effected, but is not of such importance as to require particular notice. - A patent has been granted for a machine for dressing, and another for nicking the heads of screws, which possess considerable novelty; but, as the principal novelty consists in the parts and combinations of parts which are found in a machine patented by the same inventor for cutting threads on screws, it is not necessary to describe them here. They will be described when the patent last mentioned is noticed. Five patents have been granted for improvements in cutting threads on screws. One of them is a reissue of a very old patent, which is too well known to require notice in this report. One of the above-mentioned patents is for cutting the threads on screws and nuts. The cutters are placed at the opposite ends of a revolving shaft. In cutting the thread on the screw this shaft is made to advance, endwise, the distance to which the thread extends upon the shank. In order to disengage the screw from the cutter or die, the motion of the shaft must be reversed. The blank nuts are placed in a self-acting feeder, near the opposite end of the shaft, which feeds one at each advance of the shaft into a position to be reached by the tap on the end, which is intended to cut the thread in the nut at the return of the shaft. As the shaft returns to disengage the screw, the tap at the opposite end enters the nut and cuts the thread in it. When another screw-blank is placed at the screw end, the shaft advances to cut the thread on it, the tap drawing the nut after it till it comes over an opening; and as the shaft advances, the tap is screwed out of the nut, which falls into a proper receptacle. Thus the time which would be lost in withdrawing the finished screw is devoted to cutting the screw in the nut; and the one is sure to fit the other, and the feeding and clearing the nut are effected in a simple and convenient manner. In another of the patented machines for cutting screws, the rod upon
which the thread is to be cut is held by a self centring clamp attached to a sliding carriage. The end of the rod is seized by divided revolving dies, which are pressed upon it by self-centring clamps. Thus, in every adjustment the centres are preserved. The dies are of the ordinary kind for cutting screws, but have an additional cutter combined with them too finish the thread. The bolt or rod is received by the dies, is by them smoothed, and the thread partially cut and fed to the finishing cutter. The machine, hereinbefore alluded to, for cutting the threads on pointed screws, possesses some peculiarities which are worthy of notice, and which, it is believed, will be fully understood by a perusal of the following extract from the patent: “Screws have heretofore been formed gradually tapering at the core from where the thread starts to the end, by dressing the thread at each turn; and tapering screws have also been formed, but they have been found not to hold as well as those of common construction, by reason of the taper of the main part of the core; but the nature of my improved screw consists in forming on a screw of the ordinary shape a conical point, and extending the thread of the screw with the same pitch, but gradually diminishing in width to the end of said point, by which means the screw can be entered into the wood without boring, unless the wood is very hard ; in which case it follows better, works straight, and holds more firmly than any other heretofore made. “The nature of my invention consists in moving the cutters which cut the thread of a pointed wood screw alternately with an accelerated and retarded motion as they approach the point, so as to leave the thread of the proper form down to the point and at a regular distance apart. “The construction of our modification of machinery for this purpose is as follows: The series of cutters act one at a time consecutively on the screw blank; they are all so attached to a frame or carriage that slides parallel with the screw blank as to be brought up against the blank at the proper point; this is effected by a curved stationary plate or groove, in which the rests that the tools are fastened in slide. This plate, or stationary cam, is so curved as to bring each tool up to the work as it arrives at the proper point by the progressive motion of the carriage, and thence runs parallel with the screw blank to the conical point. It is then gradually pushed forward till it arrives at the extreme apex of the point, where it leaves the blank. Each succeeding cutter is made to move forward by the regular progression of the carriage corresponding with the gain of the thread to be cut, till it arrives at the conical part of the revolving blank. At this point the first cutter is somewhat retarded as it moves along to the point. When the second cutter arrives at the conical point its motion is accelerated, and so on successively each alternate cutter is accelerated or retarded, the effect of which is to cut a fine and even thread to the apex of the conical point, and maintaining them (the threads) equidistant all the way. The motion is effected by a cam that acts upon the end of the carriage, where there is a friction roller interposed; this cam moves the carriage forward regularly. There is a small indentation in the cam, by which the motion is retarded till the first tool leaves and the second is brought into action, thence the cam is regularly progressive to the point, where, by a projection from the face of the cam, the motion is accelerated till the second cutter leaves, and so on through the series, the number corresponding to the number of cutters used. r
o “It is necessary in working a series of tools, though sufficient to cut the thread, to bring one only on to the blank at a time, and at the instant the other leaves, so as to keep a continued action upon the blank above named. If the attempt is made to cut a screw by having the blank surrounded by cutters, as in some machines, a perfect thread cannot be made, as some of the cutters will be sharper than others; and if one tool only is used, all its defects are transferred to the screw thread, which is not the case when a number of cutters are used.” * The screw-cutting machine, to which allusion has been made, for the manufacture of common wood screws, and as possessing several of the features found in the machines above mentioned for dressing and nicking screw heads, possesses much novelty, and is too complicated to be fully understood without drawings. It ought not, however, to be omitted, and it is believed that the following extracts from the patent will give a general idea of its characteristics: “The nature of my invention consists, first, in arranging the screw blanks in a continuous row when thrown promiscuously into a hopper, and delivering them one by one without the necessity of an attendant, which is effected by means of two inclined rollers, placed far enough apart to permit the shanks of the screws to hang vertically between them, so that by their rotation and inclination they cause the blanks to arrange themselves side by side, with the heads resting on and the shanks hanging between them, and thus gradually to force them towards the delivery end. “My second improvement consists in taking the blanks from the ends of the rollers and delivering them into a vertical conveying tube, by means of a slide which has an aperture in it that admits the blank, and by its motion and the oblique side of the aperture faces it horizontally and in a vertical position to the aperture of the delivery tube, down which it descends, at the same time checking the further descent of the blanks between the rollers until its return, the aperture being so formed as to permit the descent of the blanks into it from the rollers before the repetition of the delivery operation. “My third improvement consists of a pair of spring conveying fingers, which are presented to the lower end of the vertical tube down which the blanks descend, and slightly opened by coming in contact with a projection from the lower end thereof to receive the end of the blanks as it descends, and which is griped by the fingers as they are moved away; the conveying fingers projecting from a shaft, so operated by a slide and a series of cams and levers that it rotates through a part of a circle to bring the blank in a horizontal position, and then horizontally to present the head of the blank to the gripers preparatory to cutting the threads. “My fourth improvement relates to the employment of gripers jointed to a chuck or head on the end of a hollow mandrel, and connected to one end of a sliding rod within the mandrel, the other end being connected with a slide governed by a cam, the sliding of which causes the gripers to take hold of the blank just within the head, to rotate it whilst under the operation of the chasing tool, when this is used in combination with a turn-screw that slides within or on the sliding rod, and forced towards the head of the screws by a spring, so that if the blank should turn in the gripers, in consequence of the bite of the chasing or threading tool, the turn-screw will be forced into the nick in the head, and there hold it. - “My fifth improvement relates to the arrangement of the thread-cutter or chaser, and the sliding rest, the latter of which is secured to a sliding chasing frame or carriage, for the purpose of preventing the shanks of the screw from yielding while under the action of the chaser; which latter is . also properly secured in an adjustable tool holder or head, jointed by its lower end to the chasing sliding frame, the upper end sliding on a rod secured to a sway bar, one end of which is jointed to an adjusting slide, and the other governed by a cam which gives the requisite taper and point to the screw. The chasing frame is governed in its motion by a chasing cam groove on a cylinder, the groove being so formed as to move the chasing slide to carry the cutter gradually from the commencement of the thread towards the point, with a motion so regulated relatively to the rotation of the mandrel as to give the pitch of the thread, and then moved back again for another cut, one part of the groove crossing the other for this purpose ; and that part of the groove which moves the chasing slide for chasing the thread is in the form of a helix, and at the end thereof it crosses the helix with a sudden curve to run back the chaser, and at the end of the helix the groove runs into another groove, the junction of these two being provided with a sliding switch, connected with a sliding rod within the chasing camshaft, and so governed by another cam, called the index cam, that when the thread is chased the switch is shifted, which opens this latter groove to draw the chasing frame and chaser far enough out of the way to admit of the operation of the conveying fingers to supply a new blank. “My sixth improvement relates to the method of adjusting the motions of the chaser to the varying lengths of blanks, and to the different form of points, so as to insure the formation of good points on the screws by making the cam which governs the motions of the sway bar adjustable on its shast. “And my last improvement relates to the mode of changing the cams that operate the conveying fingers—the griping cam and the chasing cam— by means of an index cam, which operates sliding twitches, through the intervention of sliding rods, within the hollow mandrel and the cam shafts. “By means of these improvements I constitute an automatic machine, which performs all the operations of arranging the blanks in regular order, supplying them one by one, conveying them to the gripers, chasing the thread with any desired taper and point, and discharging the chased screw, with no other human labor than is necessary to keep the mechanism in order, and to throw a large quantity of blanks into the hopper at given intervals.” The feeding apparatus of the above described machine is used in the machines patented by the same inventor for nicking and dressing the heads, with such modifications as are necessary to adapt them thereto. The screw machinery of this country has already attained a degree of perfection which is truly enviable, especially as it gives character to so important a branch of our manufactures; and it is highly gratifying to perceive that the genius of our inventors is still rapidly adding important improvements to a department of machinery already highly elaborated and refined.
Sheet metal-Eight patents have been granted this year for improvements in machinery for working in sheet metal. Operations in this branch of manufactures are necessarily of a simple character; and after so much has been done, it does not appear to furnish room for inventions possessing striking novelty. - Three of these patents are for shears for cutting tin, &c. One of these is for cutting oval shapes, the tin being guided in its motion towards the cutters by a pattern somewhat upon the principle of turning irregular shapes. The other two patented machines have a double lateral bend at the middle of the main bow, and the cutters are connected with an additional .# bow, adjustable and sliding upon the main bow. The shafts of the cutters are both inclined to the surface of the sheet to be cut, and the bend mentioned in the main bow allows these shafts to be always nearly in the same plane with the axis of the metal holders, or clamp. The points of novelty are divided between the two patentees, the machines being substantially the same. In making vessels, such as cups, pails, &c., of that material, it has always been difficult to do the double seaming by machinery. Several patents have already been granted for improvements in double seamers, and this year, two more have been granted. The following extract from the patent will, give an idea of the one of them which seems to possess the most novelty: “I proceed to describe the working machinery; noticing, first, the two arbors, which are connected by cog wheels and turned by the crank. Two heads are affixed to the ends of these arbors, and between these heads the double seaming is performed. A pan is placed over the head on the lower arbor, so as to bring the upper edge, which is to be seamed, down between the head and a small roller hereafter described. The shape of the head should be carefully noticed. This head consists of a flanch projecting from a cylindrical surface, similar to some other machines now in use. This cylindrical surface is terminated by a shoulder that connects with a conical moulding. The level surface of the head bears first upon the edge of the pan, which is sustained by the head, (the shoulder above named coming against the bottom,) and the edge is forced to yield to the level of the head, as this is screwed down upon it by means of the screw ; and should any part of it be inclined to slip out towards the top of the pan, (as this edge is always composed of three thicknesses,) it is prevented from so doing by the little roller attached to a collar that surrounds the arbor near the head. At this stage of the operation the crank \ is turned, the pan revolves in the machine, and the edge is turned down as far as the level part of the head will turn it, while the shoulder prevents the edge of the pan from bending too far down towards the centre. After this the head must be raised a little by turning a screw attached to its box, and then the lever is brought into use to move the arbor inwards, by which the cylindrical part of the head, which is parallel with the outer surface of the lower head, is brought over the same, and then screwed down towards it by said screw, when by again turning the crank the work is completed. The outside shoulder of the upper head keeps the bottom of the pan close against the lower head. The lever passes through an aperture in the top of the frame, where it has room to be moved back and forth, and places are fitted to receive it when so moved, into which it is thrown by a spring or by its own elasticity. It also passes between