US46843A - Improved saw-grinding machine - Google Patents

Description

J. G. BAKER. SAW GRINDING MACHINE. No. 46,843. l Pate nted Mar. 14, 1865.

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JOHN G. BAKER, OF PHlLADEbPHIA, PENNSYLVANIA, ASSIGNOR., BYMESNE ASSIGNMENTS. TO HENRY DISSTON. OF SAME PLACE yIMFROV'ED SAW-@BINDING MACHINE.

Specification forming part of Letters Patent No. Whg/i3. dated March l-l, 1R65.

To ad whom ib may concern.

v lBe it known thatl, 'JOHN (ln-BAKER, of Philadelphia, Fcnnsylvania, have invented an Imprcvementin Machinery for Grinding Savv- Blades; and Ido hereby declare the following to be a full, clear, and exact description In order to enable others skilled inthe art to make and use my invention, l will now prooecd to describe its construction and operation.

0n reference tothe accompanying. drawing, which forni a part of this specification, Figure 1 is a sectional view of my improved saw-grinding machine; Fig. 2, a plan View, and Figs. 3, 4, and 5 views of the saw to illust-rate the purport of my invention.

Agrepresents a box-frame or trough, on the upper end of which rests a circular casing, B, incl'osing the greater portion of a disk-Wheel,

C, secured to the shaft D, the latter turning in the opposite sidesvof the casing, and one end ,of the shaft being furnished with a suitable hand-Wheel, a, or, in place ofthe saine,-a driving-pulley. The casingI B, with its disk- Wheel, is arranged to slide to and fro in guides b b, and is controlled by screws d d, the threads of'which are adapted to internal threads in lugs e e,projecting from the casing, the screwsl turning in the end of the frame A, onl the outside of which each screw is furnished witli a bevel-wheehf, gearing'into a similar- -wheel on the shaft E, which turns in projectionsv F F of the frame, andwhich is furnished with a hand-Wheel, t'.

" islthe grindstone, and Il its shaft, the ,journals of which turn inthe boxes I and l'. One of the latter rests on each side of the boxframe A, to which each'box'is secured by two set-screws, m nea-chI of which passes through a slot in thebox sothata limited longitudinal be imparted to the same.

Totherear end of the box I is connected 'aV rod', J, and to the rear end of the box l a similar rod,J, the latter beingjoiuted to on'earm of the lever K and the rod J' to the other arm of the same lever, through 'which passes a central pin, '01, secured to the end o f the boxframe A. One end of a link, L, is jointed to the box l', the other-end being connected to theshort arm of the bell-crank lever M, .the 'long arm of which has a forked end, embrac- --ing the curved rim tof the scroll-cani N.

A rapid rotary 'gnotion havin g been imparted to the grindstone, and the' casing B, with its disk-Wheel, having heeninoved back a short distance by means ofthe screws d,a hinged door, m, in the said casin g is opened, and the large end of a saw-blade introduced into the opening andadjusted against an inclined rib, y, .on the periphery of the disk-wheel,

small pins w w on the latter passing throughy holes in the blade, as seen in- Fig. 2. The

disk-Wheel is then turned in the direction of' thearrow, the saw thereby drawn through the opening and occupying a position between the casing B and the'wheel U, and when the latter has been turned until another inclined. rib, y, presents itself at the opening, another blade is adjusted to the Wheel in the manner described above. l

In' the present instance the wheel C is adapted to the reception of two ordinary saw- 'f blades.

TheV door is now closed. and secured, and the'casing B moved ,toward the grindstone, a portion of which projects through an opening in the casing B and bears against the blades ou the disk-wheel, which is now slowly turned in the direction of the arrow by hand or by power. As the shaft D revolves, the

scroll-cam N, through the medium of the bellcrank lever M, link L, rod J', lever K, and rod J, causes .the boxes I and l of 'the grindstone-shaft to move to and fro in ontranydirections to each other, thereby moving-the grindstone laterally and causing it to assume diEerent angles, so that'it must of necessity' grind the saw-blade thinner at some parts .than at others.

The blades ol' hand-saws of the best class areinvariahly-xnade thickeron thetoothededge than at the' back, and are alsomade thicker at thelrge than at the smaller endl of the blade.

The blade, Fig. 3, for instance, should be thickest at the joint 2 and thinnest at the point 3, the blade being thicker at 2 than itis at 5,V and thicker at 4 than it is at 3. It will be evident that the flange t of the scroll-cam N may be sc curved, and that the grindstone may have such a movement imparted to it, that the sew-blade may be reduced to the di sited taper and 'variation in thickness.

Tapering saw-blades have been heretofore ground by placing them on beveled plates secured to a disk-wheel and subjecting them to the action of a `grindstone which always revoI-ved'in the same plane. This plan involved the necessity of changing the beveled `plates to suit diiie'rent blades-an operation which caused much delay and tedious manipulation.

In my improvement the lateral movementA of the grindstone can be readily changed and adapted to different blades by a simple change of the scroll-cam' N.

It will bc evident that devices other than those shownmay be adopted for imparting a lateral motion to the grindstone from the shaft of the disk-Wheel C. Iv therefore do not de sire to confine myself to the system of rods ,and levers herein described for obtaining such Witnesses HENRY HoWsoN, CHARLES HowsoN.

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