US2749677A - Sharpener for planing machine cutter-block blades - Google Patents

Description

2 Sheets-Sheet l D. E. BURGESS SHARPENER FOR PLANING MACHINE CUTTER BLOCK BLADES June 12, 1956 Filed Nov. 18, 1952 June 12, 1956 D u ss 2,749,677

SHARPENEIR FOR PLANING MACHINE CUTTER BLOCK BLADES Filed Nov. 18, 1952 2 Sheets-Sheet 2 Fig.

@0214 701 Fee bu Qess United States Patent SHARPENER FOR PLANING MACHINE CUTTER-BLOCK BLADES Donald Eric Burgess, New Southgate, London, England Applicafion November 18, 1952, Serial No. 321,196

Claims priority, application Great Britain November 22, 1951 1 Claim. (Cl. 51173) This invention relates to devices for grinding, sharpening or honing and more especially to an electrically operated device particularly suitable for sharpening the blades of planing machines.

The invention consists of a hand grinding, sharpening or honing device comprising a motor-driven grinding, sharpening or honing wheel and a frame by which the grinding, sharpening or honing wheel may be held in grinding, sharpening or honing relation to a cutter blade on a cutter block of a planing or like machine.

Conveniently the grinding, sharpening or honing wheel is held by the frame resting on the cutter block and is checked from rotating therearound.

Conveniently also, the frame is made adjustable, e. g. for different diameters of cutter block, or angles of grinding etc.

Also the position of the grinding, sharpening or honing wheel in relation to the frame may be made to be finely adjustable in the direction of the axle of rotation of the wheel, e. g. by a micrometer screw adjustment.

In operation the hand device or tool is held in its set position by hand pressure and is pushed in the axial direction of the cutter along the blade which is to be ground, sharpened or honed.

An embodiment of the invention will be described with reference to the accompanying drawings.

Figure 1 is an end elevation;

Figure 2 a side elevation;

Figure 3 is a longitudinal section of the micrometer adjuster; and

Figure 4 shows the method of adjustment for different cutter block diameters.

In the embodiment an electric motor 1 is supported on a frame 2 and over a V-pulley 3 fitted on its output shaft and a V-belt 4, drives a grinding wheel 5.

The grinding wheel 5 is carried on a shaft 5a supported in ball bearing races 6 located in a cylindrical shell 7 which slides but does not rotate on a cylindrical support 8.

The position of the grinding wheel is adjusted by means of a micrometer screw 9 the position of which is controlled by a knurled head 10 mounted so that it may rotate in relation to the support 8 but cannot move axially in relation thereto.

The frame 2 carries an extension frame 11 having a hinged part 11a secured thereto by which the device can be rested on a cutter block of any diameter within a range (see Figure 4).

The axis of the grinding wheel is set in relation to the frame so that when the frame rests on a cutter block the grinding wheel axis is displaced in a plane therethrough and parallel to the axis of the cutter block by around 1.

The frame 11 also carries a slideway or an insert 12 which has slidably mounted therein a T-piece 13. The head of the T-piece is bevelled at 13a to keep it clear of the cutter block and the T-piece is placed with its edge immediately behind the back edge of the cutter blade 15 in the cutter block 14.

Thus by anti-clockwise hand pressure in relation to the view shown in Figure l the grinding wheel 5 may be held up to the blade 15 and the grinding wheel adjusted to sharpen it.

The device may then be slid along in the axial direction of the cutter block to complete the sharpening process over the whole cutter.

Other cutter blades in the block may be similarly sharpened and all will then be at the same position, i. e. with the same amount of cutter blade standing out of the cutter block.

Thus the blades when ground in position in the cutter blade will be set for height and angle and parallel to their length Whereas when ground away from the cutter blade the operation of setting them conveniently back in the cutter blade may be a long and tedious one and furthermore the resulting deviations as between the setting of the different blades of the cutters may be considerable.

Various modifications may be made within the scope of the invention. Thus the device may be used in association with a guide rail secured to the table of a planer.

I claim:

A portable device for grinding the straight edges of the cutter blades mounted upon the rotary cylindrical cutter block of a woodworking machine, said device comprising a frame adapted to rest upon the circumference of the cutter block and having two parallel, spaced-apart bars adapted to rest on the cutter block at opposite sides of a blade, whereby the frame is freely shiftable angularly about the circumference of the cutter block, a hinged connection between one of said bars and the frame to afford pivotal adjustment about an axis parallel with the bars to permit the device to be used upon cutter blocks of different diameters, a grinding wheel of the disc type having a radial operating face mounted upon the frame with said radial operating face disposed in a plane approximately tangential to the cutter block, an electric motor secured to the frame adjacent the grinding wheel and drivingly connected to the grinding wheel, a cylindrical support upon the frame, a shell slidable longitudinally within the cylindrical support, a shaft suspended by the shell and supporting the grinding wheel for rotation and projecting outwardly through the lower end of the cylindrical support, a screw afixed to the shell and projecting outwardly through the upper end of the cylindrical support, a nut threaded on the screw and abutting the upper end of the cylindrical support to afford micrometrie adjustment of the operating face of the grinding wheel in a direction to and from a cutter blade, a slideway upon the frame, and a slidepiece mounted for slidable adjustment in the slideway, said slidepiece being disposed below and approximately parallel to the operating face of the grinding wheel and having one end engageable with the back edge of the blade in the cutter block for checking rotation of the frame around the cutter block in one direction whereby to hold the fiat operating face of the grinding wheel in sharpening relation to the blade.

References Cited in the file of this patent UNITED STATES PATENTS 1,085,876 Redden Feb. 3, 1914 1,443,150 Schimmel Jan. 23, 1923 2,338,995 Burns Jan. 11, 1944 2,549,147 Walters Apr. 17, 1951 FOREIGN PATENTS 258,375 Switzerland May 2, 1949 501,975 Belgium Apr. 14, 1951 804,070 Germany Apr. 16, 1951

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