US1400767A - Art of grinding cutting edges - Google Patents

Description

F. H. PERRY. ART OF GRINDING CUTTlNG EDGES.

APPLICATION FILED AUG- 21, 1917.

1 ,4003'61 Patented Dec. 20, 1921.

2 SHEETS-SHEET 1.

WWWJE I F. H. PERRY.

ART OF GRINDING CUTTING EDGES.

APPLICATION FILED AUG.21,1917.

Patented Dec. 20, 1921..

2 SHEETS-SHEET 2.

arias FREDERICK PERRY, 011 BEVERLY, ItIASSACHU-SETTS, ASSIGNOR, BY

IVJIESNE ASSIGN- MENTS, T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEV A CORPORATION OF NEW JERSEY.

ART OF GRINDING CUTTING EDGES. I

Monger.

Specification of Letters Patent.

Patented Dec. 20, 1921.

Application filed August 21, 1917. Serial No. 187,402.

of Beverly, in the county of Essex and State of Massachusetts, have invented certain Improvements in the Art of Grinding Cutting Edges, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the several figures.

This invention relates to the sharpening or grinding of cutting edges and more particularly those of cooperating knives of clifferent form such as are used, for example, in jointing machines for trimming the edges of the shanks of shoes. In machines of this class there are, as fully explained in my Patent No. 1,080,605, dated June 25, 1912, a reciprocating trimming knife, having opposite cutting edges, which operates upon the inner and outer edges of the shank portion of a shoe to give it the proper outline, and corresponding knives, called chopping knives, which reciprocate parallel to the breast of the heel, serving to out off the chips left by the trimming knife. As has been pointed out in the previously mentioned patent, the trimming and chopping knives, while different in form, must have one contour common to both to enable the chopping knives to just sever the curved chips of the trimming knife without cutting into the shank. This common line lies along the edges of the trimmingknife, as viewed longitudinally of the body, and along the edges of the chopping knives, seen laterally. Obviously, if these edges are to cut to precisely the same points throughout their lengths, they must be so ground as to preserve always this identity of contour. An important object of this invention is the provision of an improved method Whereby one of a plurality of cooperating knives may be so ground that in their use they will out along their entire edges, point for point, to a common line, and, moreover, that this relation shall be maintained as both knives are ground. This object is attained by employing a templet, for example, one of the knives, to provide a guide for grinding another. Thus, in sharpening the knives of a jointing machine, the edge trimming knife may serve as a templet or in the formation of such a templet for the chopping knives.

The invention also provides novel apparatus by which my improved method may advantageously be carriedinto effect. In this a support for the knife or knives to be sharpened and a grinding surface, as the edge of a rotatable abrasive Wheel, are movable relatlvely to subject the entire cutting edge to the grlndmg action, and the cooperating knife is utilized to determine the path of this feeding movement.

Since some machines,as the jointing mach nes previously referred to, employ two knives operating upon opposite sides of the work, it is desired to furnish means for qulckly and conveniently arranging-for the grinding of both knives. In the illustrated apparatus this is attained by using a single templet, as the trimming knife of the joint mg machine, for grinding both the cooperatmg knives,'this templet being movable, pref erably by reversal, afterone knife has been ground to a position to adapt it for the grinding of the opposite knife. By suitable connections between the templet and knife support the preparation of the cooperating elements to grind the second knife may be and as shown are made automatic.

Various other features are embraced by my invention as will be made evident by the following description and claims.

In the accompanying drawing- Figure 1 is a side elevation of one embodiment of my improved apparatus, shown in position upon a portion of the frame of the machine to which it maybe attached, the latter being in section;

Fig. 2 is a perspective view of the grinding apparatus;

Fig. 3 is a partial top plan view of the knife-holding and guid ngelements. and

Fig. 4 is a detail perspective of a portion of the connections for shifting the stops.

Upon the frame 10 of a machine, the knives of which are to be ground, is secured a bracket 11 furnishing a support for the active elements of the apparatus of the present invention. This bracket carries a table 12 from which rises a standard 13 having journaled in itthe shaft 14; of a suitable grinding wheel 15. Fast upon the grinding wheel shaft is apulley 16 which may be driven by belt gearing from a shaft upon themachine to which, the grindingapparatus is attached- 45 the knivesC and Dginto, contact with the Depending from the under side of the table 12 are projectlons 17 having formed .in their inneredges ways to receive a slide 18. At the rear of the slide 18 is a lug 19 in which is rotatably mounted a screw 20 threaded into an enlargement beneath the table. Carried upon'the front face of the slide are blocks 21, 21 in alined bores in which is mounted a guide rod 22 having a limited longitudinal movement, as will hereinafter appear. Movable upon the rod are bearing members 23, 23 joined by a curved yoke 24 and carrylng a supporting arm 25 whichextends upthrough an openj in position.

jing- 26 in the table 12. The arm 25 carries at its upper extremity a knife holder 27 in which are two vertical slots 28, 28 lying adjacent and parallelv to one another and having at their tops pairs of ways 29 29v to receive the shanks of' the knives to be ground. 'A screw 30 passing through, an.

opening in the holder below the ways and being threaded into the farther side serves to draw the ways together and thus gives a common means for clamping both knives be ground have oppositely curved cutting ;edges'0 and (Z which enable them to work upon the right and left sides of the shoe shanks These knive's,fwhen fixed in the ways'in'the holder, maybe so positioned that their adjacent cornerslie just at the opposite edges of the grinding surface of the wheel'l5. To determine the length of the paths through which the knives are moved in their grinding,-stops are provided consisting of screws 31, 31 threaded through arms 32, 32 secured to the ends ofthe guide rod 22. The knife holder is limited in its movement away from the grinding wheel as the arm'25 is turned aboutltherod 22 by contactofthe arm withthe outer edge of the opening: 26 in the table 12, and may be swung therefrom to bring the edges of wheel. To allow free inspection of the knives during their grlnding the knife holder 27 is pivoted upon the arm 25 by means of a screw 33 and is locked in normal position by a'spring-pressed piu'34 entering an opening in the face of the boss upon which the holder turns.

From one side of thearm 25 projects a branch arm 36 carrying a holder 37 in the form of a crank disk for the templet by which. the chopping knives C and. D are to be guided in the desired paths over the grinding wheel. In accordance with the illustrated embodiment ofmy invention,

this templet is furnished by a trimming "knife T which cooperates in the jointing machine with the chopping knives. fit-the outer edge of the crank d sk is an angular portion provided in its inner face with dove- In the present instance, the chopping knives C and D which are to;

1 ,eoonev tail ways 38to receive the correspondingly formed portion of the trimming knife shank, the knife being secured in theuvays by'a clamping screw 39. At the. rear of this templ'et' is a guide member furnished by the point of a screw 40 which is threaded through the upper end of an arm 41 secured to the front face of the 'slide 18. The end of'the arm through which the screw 40 passes is slotted, the portions being drawn together by a screw 42 to fix the guide screw against rotatlon. The screw 40 153 so ad usted through 1ts arm wlth respect to the templet that when the latter is in contact with the point of the screw the knife holder will be moved sulficiently'near to the edge of the grinding wheel to remove thev desired. amount of material from the knives C and D. As the support is slid longitudinallyrupon the rod 22 the engage ment between the point of the guide screw and templet will cause the holder to describe a path exactly correspondingto said templet and therefore cause the chopping knife to be ground to the precise contour line of the trimming knife. The screw 20, previously described as cooperating with the lug upon the, slide 18 enables the user of the apparatus to. change the vertical position of the kmves C and D with respect to the grinding wheel, thus permitting the use of wheels of different diameter. an adjustment of this screw, in connection with an alteration in the positioniof the guide screw 40, changes the angle at which the knives are presented to the grindingwheel and therefore the bevel at which they are ground. v

To enable the operator to. grind both knives with the same templet, the templet holder is'preferably mounted upon. apivot pin 48 the axis of which is in alinement with theaxis of the guide screw. Fast upon the pin 43 with the holder dlsk is an arm 44 carryingat its outer extremity a spring,

pressed pin 45, which may enter a. hole 46 atone end of a segmental surface at the top of the branch arm 36 or a corresponding hole at the opposite end of the segment with i will be reversed, it now directing the guide screw 40 along its curved surface to the left instead of to theright to provide for the gr nding of theother kn fe D having the opposite curvature. At thesame timeitae templet is reversed, the stops 31, 31 are preferably automatically adjusted to fix the limits of the path through which the particular knife to be ground is to move. Projecting from the inner side of the holder disk 37 is a pin l7 having a ball head furnishing a universal connection for a rod 48, which at its other end is articulated upon a like pin 49 projecting from the upper arm 50 of a bell crank lever pivoted at 51 upon the slide 18. The lower arm 52 of the bell crank carries a pin 53 entering a circumferential groove 54 near the center of the rod 22. As the templet is reversed, as by moving the pin 45 from its illustrated position into engagement with the hole t6, the pin 47 on the templet-holding disk is moved f om its uppermost to its lowermost position, causing the connecting rod d8 to swing down the arm 50 of the bell crank lever and carry the pin 53 to the right. This, engaging the slot 54;, moves the rod 22 through the bearing members 23 so that the stop screws 31 are positioned to provide for a travel of. the knife support upon the rod from the righthand contact screw to that at the left and fix the limits of the feeding movement of the knife D as was provided for in the case of the knife C with the stop pin 45 in engagement with the opposite hole.

In the performance of my novel method by the use of the apparatus described both the chopping knives of a jointing machine are clamped in the holder 27 with their adjacent corners in the same transverse line and the trimming knife with which the chopping knives are to cooperate or a templet constructed therefrom is introduced into the holder 37. Then the apparatus is adjusted by means of the screw 20 and the guide s row 40 to give the proper relation of the edges to be ground to the edge of the wheel and to produce the desired bevel. With the pin f?) in one of the holes in the segment, the support 25 is moved along the rod between the stops to grind one of the knives. This having been accomplished, the trimming knife which is being used as the templet is reversed by carrying the pin 45 into the other hole in the segment and the companion chopping knife similarly ground.

Having thus described my invention, what I claim as new and ters Patent is 1. The method of sharpening upon an abrasive surface one of a plurality of curved knives having cutting edges of different form, which consists in supporting one knife in a grinding position, holding the other knife at an angle to the first, and moving the knives together to present the edge of the first knife to the abrasive surface while utilizing the transverse contour of the second knife as a guide.

2. The method of sharpening a pair of desire to secure by Let oppositely formed knives which in use 00- operate with another knife tocut to common lines which consists in employing the lastnamed knife as a templet in grinding one of the pair of knives and then reversing the templet in grinding the other knife of the pair.

3. In an apparatus for grinding one of a plurality of cooperating knives, a grinding member, a support for one of the cooperating knives, said member and support being relatively movable to permit the fee'd of these elements by one another, means including a guide in the form of another of said knives for determining the path along which this feeding movement shall occur, and means controlled by the guide by which the length of said path may be variably determined.

4;. In an apparatus for grinding one of a plurality of cooperating knives of different form, a grinding member, a support for one of the cooperating knives, said member and support being relatively movable to permit the feed of these elements by one another, a second support for holding the other of the cooperating knives in a plane substantiall perpendicular to the plane of the first-mentioned knife, whereby said feeding movement follows a path corresponding with the profile of the last-mentioned knife, and means for mounting the supports for angularmovement with respect to the grinding member.

In an apparatus for grinding one of a plurality of cooperating knives of different form, a grinding member, a support for one of the cooperating knives, said member and support being relatively movable to permit the feed of these elements by one another, a second support for holding the other of the cooperating knives in a plane substantially perpendicular to the plane of the first-men tioned knife, whereby said feeding movement follows a path corresponding with the profile .of the last-mentioned knife, and means for holding said path-determining knife in a plurality of positions to adapt it for grinding different knives.

6. In an apparatus for grinding one of a plurality of cooperating knives, a grinding member, a support for one of the cooperat ing knives, 'sa-id'member and support being relatively movable to permit the feedof these elements by one another, means including another of said knives for determining the path along which this feeding movement shall occur, means for holding said pathde termining knife in a plurality of positions to adapt it for grinding different knives, and means controlled by the position of the pathdetermining means for presenting different knives to the grinding member. s

7. In an apparatus for grinding one ofa plurality of cooperating knives, a grinding member, a support for one of the cooperating knives, said member and support being n 1 relatively movable to permit the feed or these elements by one another, means including the tr nsverse side face of another of said knives for determining the path along which this feeding movement shall occur, and

. means for holding said pathedetermining knife in reverse positions to adapt it. for grinding oppositely formed knives.

' 8.111 an apparatus for grinding one ofa plurality of cooperating knives, a grinding member, a support for one of the cooperating knives, said memberan d support being relatively movable to permit the feed of these elements by one another, means 1ncluding another of said knives for determnnng the path'along which this feeding movement shall occur, means for holding said path-determiningknife 1n reverse positions to adapt 1t for grinding oppositely formed knives,

. and means controlled by the position of the path-determining means for presenting one 'or theother of the knives to the grinding member;

9. In an apparatus for grinding one of a plurality of differently formed cooperating knives-adapted for different cutting operations, a grinding member, a support for the :knife tobe ground, said member and support being ,relativelymovable to permit the feed of these elements by one another, a holder constructed and arranged'to receive one of the differently operating knives and support it in a plane substantially perpendicular to the plane of the knife to be ground, and means cooperating with the last-named knife to guide thefeeding movement.

10. In an apparatus for grinding one of a V plurality of differently formed cooperating knives adapted for different cutting operations, a grinding member, asupport for the knife'to be ground, saidmember and support being relatlvelymovable to permit the feed of these elements by one another, a

holder constructed and arranged to receive one of the differently operating knives and support it in a plane substantially perpendicular to the plane of the knife to be ground, and means cooperatin with the last-named knife to guide the feeding movement, said means and guide knife being relatively adjustable toward and from one another.

, 1 1. In an apparatus for grind ng the chopping knives of machines for operating upon the shanks of shoes by trimming kn ves, a

grinding wheel, a support for the chopping knife and a reversible support for a shanktrimming knife movable together, and a member cooperating with the trimming knife for guiding the chopping knife over a the wheel.

12. The combination with i a grinding wheel, ofa support provided with means for mounting thereon a plurality of knives to be ground a movable templet, guiding means contacting with the transverse surface or profile of the templet, and means operable in the movement of the templet for presenting different knives; to the grinding wheel.

13. The combination with a grinding .templet, a stop for the support, and connections operable in moving the templet for changing the position of the stop.

15. The combination with a. grinding wheel, of a support provided with means for clamping thereon oppositely formed knives to be ground, a templet holder pivoted upon the support, a guide point situated in alinegient with the pivotal axis of the templet holder, andconnections operable in swinging the templet. about its pivot for changing the relation of the knives to the grinding wheel.

16; In a grinding apparatus, the combination with a frame, of a grinding wheel rotatable thereon, a support movable in the frame and being provided with means for clamping thereon oppositely formed knives to be ground, a movable stop for the support, va templet holder pivoted upon the support, a guide for cooperation with the tem-' plet, a lever fulcrumed upon the frame, connections between the templet holder and lever, and means cooperating with the lever to rock it in the movement of the holder to move the stop and'thereby adapt the apparatus for grinding theknife other than that 7 previously ground.

17 In a grinding apparatus, the combination with a frame, of a grinding wheel rotatable thereon, a movable support, a guide rod therefor, a knife holder-situated adiacent to the grinding wheel and being pivoted'upon the support, means for fixing the knife holder in different angular positions with respect to the grinding wheel, a templet holder carried by the support, and a guide for cooperationwith the templet.

18. In a grinding apparatusthe combination with a frame, of a grinding wheel rotatable thereon, a movable support, a holder provided with pairs of grooves, means c0mmon to the pairs of groovesfor clamping two knives to be ground, atemplet usable in grinding either knife, and a: guide member for cooperation with the templet.

19. In a grinding apparatus, the combination with a frame, of a grinding wheel r0- tatable thereon, a movable support, a guide rod therefor, stops carried by the guide rod at opposite sides of the support, a knife holder and a templet holder carried by the support, and a guide member for contact with the templet,

20. In a grinding apparatus, the combination with a frame, of a grinding wheel rotatable thereon, a guide rod provided with a groove, a stop carried by the guide rod, a support movable along the guide rod, a knife holder fixed to the support, a templet holder pivoted upon the support, a lever fulorumed on the frame and having a projection engaging the groove in the guide rod, connections etween the lever and templet holder, and a guide member for contact with the templet.

21. In a grinding apparatus, the combination with a frame, of a grinding wheel rotatable thereon, a guide rod providedwith a groove, a stop carried by the guide rod, a support movable along the guide rod, a knife holder fixed to the support, a templet holder pivoted upon the support, a lever fulcrumed on the frame and having a projection engaging the groove in the guide rod, connections between the lever and templet holder, a guide member for contact with the templet, and means for fixing the templet in either of two extreme positions.

22. The combination with a grinding wheel, of a support provided with means for mounting thereon a plurality of knives for operating at different angles, and means for varying the position of the support with relation to the grinding wheel to correspond to the operating positions of the knives.

In testimony whereof I have signed my name to this specification.

FREDERICK H. PERRY.

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