US2062352A - Apparatus for grinding serrated cutting blades - Google Patents

Description

H. J. CRINER APPARATUS FOR GRINDING SERRATED CUTTING BLADES 2 Sheets-Sheet 1 Filed March 4, 1935 INVENTZDR.

Dec. 1, 1936.. H. J. CRINER 2,062,352

APPARATUS FOR GRINDING SERRATED CUTTING BLADES Filed March 4, 1955 2 Sh eets-Sheet 2 INVENTOR.

ATTORNEY:

Patented Dec. 1, 1936 UNITED STATES PATENT omen APPARATUS FOR GRINDING SERRATEID' cur'rme an mus Harry J. Criner, Davenporfllowa, assignor of one-half to A. G. Bush, Davenport, Iowa Application March 4, 1935, Serial No. 9,260

8 Claims.. (01. 51-72) My invention relates to new and useful improveor from serrated strips of metaland for sharpeningold blades. I I attain these objects by the means illustrated in the accompanying drawings, in which,. Figure 1 is an end elevation of my apparatus; Figure 2 isa plan view of the same; I

Figure 3 is an enlarged cross-sectional detail of a part of the tilting table, blade support and grinding wheel on the line 3-3 of Figure 2;

' Figure 4 is an enlarged detail showing one of the guidingkeys and grooves engaging same in section on the line 4-4 of Figure 1;

Figure 5 is an enlarged detail of a blade mount-v ed in the blade support and showing a portion of the grinding wheel in section;

5 Figure 6 is a plan view of an'alternate form of my invention employing a plurality of grinding preferably made of a heavy flat casting adapted to seat upon a bench, table-or other support'and may be cast-hollow if desired, to reduce weight.

, At the rear of the base a projecting boss, 2,is'

formed integral with the base and the boss and base are bored out to receive a post or column, 23. I A collar, 24, is slidingly mounted upon the post,

"23,- with a set screw, 24, by which it may berigidly secured at any desired height upon the '.column, 23.

A sleeve, 22, is slidingly and revolvably mounted upon the-column, 23,above the collar, 24, and is provided with a set screw, 22', by which it may' be locked in a given position.

This arrangement of a lockable sleeve combined with. a lockable collar, has great advantages in'the way of adjustability. In the grindi1 g of blades, it is necessary to adjust the height )f' the grinding wheel to 'a nicety relative to the position of the blade. With the arrangement I have shown, if it is desired to lower the grinding wheel say one one-hundredth of an' inch, the set screw, 24', upon the collar, 24. may be loosened and the collar moved downward far enough to insert a feeler gauge one one-hundredth of an inch in thickness between'the collar,- 24, and the sleeve, 22, The collar may then be pushed upward against the feeler gauge and held in that 5 2 position while the set screw, 24, is tightened.

.The set screw, 22, may then be'loosened, the

.feele'r, gauge withdrawn'and the sleeve, 22, allowed to slide down one one-hundredth of an inch so as to rest upon the collar, 24 The set screw, 22', 10

may then be tightened and the grinding wheel will have been lowered one one-hundredth of an,

.inch.

Simflarly, if it is desired to raise the grinding wheel acne-hundredth of an inch, the set screw, 15 22', is loosened, the sleeve, 22, raised slightly and a feeler gauge inserted between the sleeve, 22, and collar, 24. The sleeve may then be lowered to rest upon the feeler gauge and the set screw, 22',

tightened. The set screw, 24', may then be 0 loosened,,the feeler gauge withdrawn, and the collar, 24, moved upward in contact with the sleeve, 22, and the set screw, 24', again tightened.

. In this way, the grinding wheel willhave beenraised one-hundredth of an inch.

It is understood, of course, that the contacting surfaces of'the collar, 24, and the sleeve, 22, must be ground and polished to 'a very high degree to permit of such fine adjustments. It is obvious,

also, that the use of the collar,, 24, with the set 30 screw, 24', combined with the set screw, 22', forms a double locking means to secure the sleeve, 22,

at the desired height. A bracket, 2 I, is formed integral with the sleeve,

- 22." A motor, i8, has its; foot, J8, bolted to the 35 bracket, 2|, with bolts or cap screws 20 and 20', The bracket and foot of themotor are made .heavy enough to furnish a rigid support for the motor and the motor shaft, 26, is elongated and I made heavy enough to support oneor more grind- 4o 26, threaded upon the outer end of. the shaft, 26.

Upon the base, I, I form lugs. 2, which maybe cast integral with the base. Upon the lugs, 3,

I mount pivotally, lugs, 6,which are .formedintegral with the table, 5. The-lugs,- 6, are secured to the lugs, 3, by a'pivotbolt, 8, which permits the table, 5, to tilt, and the nuts, 8'. upon the as The upper face of the support, 9, is beveled at desired angle to the top of the base, I.

'Uponthe table, 5, I mount a blade support, 9. The top of the table, 5, and the bottom of the support, 9, are ground to smooth faces so that the support, 9, will slide readily upon the table, 5.

a suitable angle to assist in forming the proper angle or bevel at the cutting edges of the blades.

Pins, l and II, are rigidly secured in the,sup' port, hand spaced apart the necessary distance to accommodate the desired cutting blade, ll,/to

be ground. In mounting the blade, I 3, upon thesupport, 9, the usual hole in one end of the blade,

I3, is placed over the pin, 10, and the hole in the opposite end of the blade, i3,- is engaged by a hook, l3, formed upon an extended end of a tension spring, 12, the opposite end of which is hooked over the pin, Ii. The spring, I2, is made of sumcient strength and size to apply the necessary strain to the cutting blade while being ground inorder to hold it rigidly upon the support, 9-.

A plurality of dowel pins, 0', are secured in the support,9, spaced on opposite sides of the grinding wheel and contact with the rear edge of the blade, i3, being ground so as to prevent displacement thereof rearwardly. The dowel pins, 9', are mounted in suitable openings in the upper face of the support, 0, and a pluralityof open nfl 9", may be provided positioned as required for blades of different widths.

In order to properly gauge the support, 9, for

the successive serrations to be ground in the blades, ",1 provides. plurality of rectangular grooves, I, extending laterally in the bottom face thereof. Rectangular keys, I, are rigidly united grooves, 1'.

to the upper face of the table, I, extending parallel to the grinding wheels, II, and to the v grinding the blades at high speed, it is necessary to provide some means for In order to permit cooling. same and I mount on my machine a waterpipe, I1, with a nozzle formed at the end thereof to project the water to the point of contact between the grinding wheels and the blades. This waterpipe, l1, may belocated at a point which will project vthe water to the point of contact between the grinding wheel and the blade,

.tothebestadvantage. Imake no claimtoany particular position of the wa'terpipe, l1, and it is obvious that either water or any other suitable coolingifluid may be employed.

In the operation of my machine, the support, Q, is 'slidback upon the table, I, to the'position shown in dotted lines in Figure 2,'and the blade placed thereon asalready described.

The support is then slid along the top of the table, I, in position to grind the first serration' or scallop and the support is then pushed under the grinding wheel, l5, until it'is ready to contact with the wheel. The table, -'i,-is then adjusted j to the desired angle and the motor started. The

support, will then be guided by the keys, I,

'- and then slidforward againupon the keys, 1,

ttii-grind the next succeeding scallop or serraon, llf.-. I The grinding wheels have a curved periphery,

any

ll, of thedesired'configuration. The grinding wheels may be made of emery or carborundum or faced with diamond dust or other abrasive so as to stand long wear without requiring redressing, but may be redressed as necessary in the usual wellknown manner.

with both front and rear edges straight or if desired, the cutting edge may be stamped out into scallops of the desired configuration before being ground.

The points between the scallops will form teeth, i4, and the scallops will be uniformly beveled on both sides by the grinding process. When the blade has been entirely ground upon one side, the support, 9, will be slid back and the blade turned over and replaced, and then ground upon the opposite side in the same manner as above described. The number of keys, I, may be varied to suit the requirements of each particular case. In many instances, a single key centrally placed, will be suf- The blanks forthe blades, l3, may be formed flcient, but in any event, the keys should be so" formed and the number'of them so arranged as to insure parallel travel of the support forwardly in its different adjusted positions and to insure uniformity in the scallops or serrations, ll;

In order to speed up the operation of grinding,

a plurality of similar wheels may be mounted upon the shaft, 26, either directly or by mounting them upon a sleeve, it, which in turn may be rigidly secured upon the shaft, 26.

when two adjacent scallops, M, are ground at grinding operations for each side of the blade, but

they may be arranged to grind alternate scallops,

so that-only two grinding operations will be necessary for-each side and when driven at a more moderate speed, they may be arranged to cut all of the scallops on one side ofthe blade at a single grinding operation. The eifect of cutting all the scallopsat once, will more than make up for the 'loss of time in slowing down the speed of the grinding wheels. I I Y The upper corner of the support, l, may be groundsuflicient to accommodate the grindingwheel before the blades are placed thereon if desired or it may be ground at the same time that the blade placed thereon is ground.

It is obviousthat various equivalent means of gauging or positioning the support, 9, may be utilized and various modifications may be made in-my apparatus without departing from the spirit of my invention'and I do not limit my claims to the precise forms shown in the drawings.-

It is obvious that this process permits blades to be ground while'heldin a straight position and 'without any bending and will obviate the delays incident to placing a bladeupona curved support and in grinding a single time.

I claim: p I v 1. A blade grinding machine comprising a-fixed base, a column united-thereto,- a bracket adjustably mounted upon the column and slidable thereon, a collar adjustably mounted upon the column below and adjacent the bracket and slidable on 7; curved to cut a scallo or the column, a motor with extended shaft mounted serration or scallop at a ing ground in a succession of uniformly progres sive longitudinal positions.

2. A blade grinding machine comprising a base,

a column united thereto, a bracket adjustably mounted upon the column carrying a motor with extended shaft, a plurality of spaced grinding wheels keyed to theshaftreach having a convex periphery, means adapted to support and carry a I blade into engagement with the periphery, a table tiltably mounted upon the base, a blade support slidable upon the table, and means coacting between the table and the blade support adapted to guide 'the support in predetermined successive, uniformly spaced parallel lanes of travel to the grinding wheels.

3. A blade grinding machine comprising a base, a fixed vertical column united thereto, a bracket adjustably mounted upon the column with means permitting fine vertical adjustment thereof and adapted to rigidly secure such bracket in its adjusted position upon the column, a motor mounted upon said bracket with anextended horizontal shaft having a grinding wheel with convex periphery keyed to such shaft, and means supported above the base adapted to rigidly support and to carry a slicing blade into engagement with the peripheryo-f the grinding'wheel in a plurality of uniformly spaced successive positions longitudinally of the blade and at a right angle td the plane of rotation of the grinding wheel, and to hold such blades straight while being ground.

4. A blade grinding machine comprising a base,

a fixed vertical column united thereto, a bracket adjustably. mounted upon the column with'means permitting both coarse and fine adjustment thereof and adapted to rigidly secure such bracket in its adjusted *position upon the column, a motor mounted upon said bracket with an extended horizontal shaft having a grinding wheel with convex periphery keyed to such shaft,- and means supported above the base adapted to support and uniformly spaced successive horizontal positions and at right angles to the plane of rotation of the grinding wheel and to hold such blade straight while being ground. I Y.

5. A blade grinding machine comprisinga horizontal base, a fixed vertical column united there-' to, a bracket adjustably mounted upon the column with means permitting fine adjustment thereof vertically and adapted to rigidly secure suc bracket in its adjusted position upon the column, amotor mounted upon said bracket with an extended horizontal shaft having a grinding wheel with convex periphery keyed to such shaft, a tiltable table pivotally mounted upon the base under and spaced from the grinding wheel, an

extended wedge-shaped support manually slidable upon the table and means united to the support adapted to secure a blade "upon the upper face thereof and to hold said blade under tension in progressive contact with the grinding wheel while being ground. v 6. A blade grinding machine comprising a-horizontal base, a fixed vertical column united thereto, a bracket adjustably mounted upon the column with means permitting fine adjustment thereof vertically and adapted to rigidly secure such bracket in its adjusted position upon the column,

a motor mounted uponsaid bracket with an extended horizontal shaft having a grinding wheel with convex periphery keyed to such shaft, a tiltable table pivotally mounted upon the base under and spaced from the grinding wheel, an extended wedge-shaped support manually slidable both longitudinally and transversely upon the table, and means united to the support adapted to secure a blade upon the upper face thereof and to hold said blade under tension in progressive con-.

tact with the grinding wheel while being ground.

7. A blade grinding machine comprising a horizontalbase, a fixed vertical column united thereto,a bracket adjustably mounted upon the column with means permitting fine adjustment thereof vertically and adapted to rigidly secure such bracket in its adjusted position upon the column, a motor mounted upon said bracket with an extended horizontal shaft having a grinding wheel with convex periphery keyed to such shaft, a tiltable table pivotally mounted upon the base under and spaced from the grinding wheel, an extended wedge-shaped support manually slidable upon the table, and means united to the support adapted to secure a blade upon the upper face thereof and to hold said blade under tension in progressive contact with the grinding wheel while being ground, and guiding means adapted to guide the support in a plurality of uniformlyspaced progressive lines of travel parallel to the plane of the grinding wheel.

8. A blade grinding machine comprising a horizontal base, a fixed vertical column united there to, a. bracket adjustably mounted upon the column with means permitting fine adjustment thereof shaped support manually slidable both longitudinally and transversely upon the table, and means united to the supp rt adapted-to secure a blade upon the upper face thereof and to hold said blade under tensionin progressive contact with the grinding wheel while being ground.

HARRY J. CRINER.

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