US3581446A

US3581446A - Sharpeners for cutting reels

Info

Publication number: US3581446A
Application number: US760239A
Authority: US
Inventors: Wilmer E Witt; Eugene A Sousek; Clyde A Clish
Original assignee: Koehring Co
Current assignee: Hiniker Co
Priority date: 1968-09-17
Filing date: 1968-09-17
Publication date: 1971-06-01
Anticipated expiration: 1988-06-01

Abstract

A rotatable grinding disc is supported on the frame of a cutting reel for movement back and forth along a track tube of the knife cylinder. The tube is rockably mounted to provide for swinging of the grinding disc into and out of a position where the end face of the disc is engageable with one of the knives. There is means including a cam arm and mechanical linkage for transmitting rocking motion to the knife cylinder as the grinding stone progresses axially of the latter so that all portions of the cutting edge of the angled or helical knife are presented in the same relationship to the end face of the stone, and there is manual indexing to bring a new knife into a position to be sharpened.

Description

United States Patent Primary ExaminerWilliam R. Armstrong Attorney-Morse" & Morsell ABSTRACT: A rotatable grinding disc is supported on the frame of a cutting reel for movement back and forth along a track tube of the knife cylinder. The tube is rockably mounted to provide for swinging of the grinding disc into and out of a position where the end face of the disc is engageable with one of the knives. There is means including a cam arm and mechanical linkage for transmitting rocking motion to the knife cylinder as the grinding stone progresses axially of the latter so that all portions of the cutting edge of the angled or helical knife are presented in the same relationship to the end face of the stone, and there is manual indexing to bring a new knife into a position to be sharpened.

PATENTEI] Jun 1 19m SHEET E [1F 4 T. R O T N w E V N ATTORNEYS PATENTED Jun 1 m:

SHEET 3 [1F 4 AT TORNEY S SI-IIARPENERS FOR CUTTING REELS BACKGROUND OF THE INVENTION l. Field of the Invention:

The present invention relates to a sharpener for rotatable cutting reels of the type having angled or helical knives, and is particularly suited for permanent or removable attachment to the frame of a forage harvester cutting reel.

2. Description ofthe Prior Art Heretofore sharpeners for cutting reels have commonly comprised nonrotatable sharpening stones which are adapted to be reciprocated back and forth, usually by manual action, the sharpening being done by rotating the cutting reel. In our copending application Ser. No. 46,192, filed June 15, 1970, a continuation of application, Ser. No. 687,528, filed Dec. 4, 1967, a sharpener is disclosed embodying certain features in common with the sharpener of the present invention. In the copending case there is also means between the reel-rocking mechanism and the reel which is responsive to return of the carriage to starting position, after sharpening of one blade has been completed, for automatically indexing the reel to bring another blade into position. This mechanism is necessarily quite complicated and furthermore automatic indexing in addition to the automatic reel-rocking is not always desired or necessary.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved sharpener having improved means for supporting the grinding stone so that it is accurately guided in its axial movement, the arrangement providing for swinging of the stone into and out of operative position, and the invention including relatively simple mechanism for automatically rocking the cutting reel as the rotatable grinding stone is axially fed, whereby all portions of the knife being sharpened are maintained in the same relationship to the stone regardless of the angled or helical shape of the knife, said mechanism including a provision for simple manual indexing of the knife cylinder to bring a new knife into sharpening position after sharpening of one knife has been completed.

A more specific object of the invention is to provide a sharpener as above described including a supporting tube having axial track grooves which coact with wheels on the grinder carriage to guide the carriage in axial movement, said tube being mounted for rotation whereby the tube will rock to permit swinging of the grinder into and out of operative position, the sharpener assembly being readily removable but also being swingable to an inoperative position so that it may remain con nected while the cutting reel is being used for cutting purposes.

A further object of the invention is to provide, in a sharpener for cutting reels of the class described, an improved actuator arm and indexing hub assembly adapted for quick connection and disconnection from the end of a cutting cylinder shaft, said assembly providing for automatic transmission of rocking motion to the cutting reel during sharpening, and also providing for manual disengagement of the hub assembly from the actuator arm assembly whereby the reel may be manually indexed to bring a new knife blade into position for sharpen ing, there being means for quickly locking the reel in its new position.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings, in which the same reference numerals designate the same or similar parts in all of the views:

FIG. I is a generally rear view of the sharpener, partially in section, and taken approximately on the line I-I of FIG. 2;

FIG. 2 is a transverse sectional view taken on the line 2 2 of FIG. I;

FIG. 3 is a fragmentary detail view, partially in transverse section, showing the actuator arm and indexing hub connected to the splined end of the cutting reel shaft;

FIG. 4 is a fragmentary perspective view showing the shar pening device attached to the frame ofa cutting reel, with the grinder tilted down and in starting position;

FIG. 5 is a fragmentary perspective view somewhat similar to FIG. 4 but showing the grinder at the far end of a grinding pass about ready to start a return trip;

FIG. 6 is a fragmentary perspective view showing the sharpener associated with the frame of a cutting reel, the grinder being tilted up to an inoperative position;

FIG. 7 is an exploded perspective view showing the principal parts which make up the actuator arm and indexing hub assembly; and

FIG. 8 is a fragmentary-perspective view showing a straightangled blade, the cutter being capable of sharpening such a blade as well as the helically angled blade illustrated in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly first to FIG. I, the sharpener includes a baseplate 20 having end flanges 2I. L-pins 22 have threaded engagement with nuts 23 secured to the end flanges and said pins have ends which are suitably engageable with end plates 24 of the track tube frame, the end plates being connected at their lower ends by a bar 25. The end plates are also removably held in assembled position by capscrews 26 (see FIG. 4), but may be tilted on the L-pins when the capscrews are removed.

A track tube 27 is rotatably connected between the end plates 24 by means of bolts 28 which extend through end discs 29 having circular flanges 30. The end discs extend through circular openings in the end plates 24 and are rigidly bolted to the ends of the track tube 27 so that the and discs rotate in the end plates 24 when the track tube is rotated. A guard 31, which is L-shaped in cross section, has end brackets 32 which are rigidly connected to the track tube: 27 so thatthe guard 31 rotates with the track tube. Also rigidly connected to one end of the track tube is an L-shaped bracket 33 to which a fitting 36 is pivoted as at 35, one end of the cam arm 34 being rigidly connected to the fitting 36 and the other end being rigidly connected to a fitting 37. The fittings .36 and 37 are also connected by a back-bracing rod 38 (FIG. 6).

Mounted on shafts 39 which extendl through the track tube are sprocket wheels 40 around which an endless chain 41 is trained. One of the shafts also carries another sprocket wheel 42 which is connected by an endless chain 43 with a smaller sprocket wheel 44 keyed to a shaft 45. The wheel 42 is arranged to drive the juxtaposed sprocket wheel 40 and hence the endless chain 41. The shaft 45 is suitably journaled transversely of the track tube and has a squared end to which a crank 46 may be removably connected through a hole 47 in the wall of the guard 31. A chain guide bracket 48 has a slot 49 which coacts with a pin 50 projecting from one of the chain links. Thus as the chain is caused to move through operation of the crank 46 the pin 50 will cause movement of the bracket 48. As the pin approaches the end of a stretch and passes around the sprocket, it will move downwardly in the slot 49 so that, when it is in the return stretch, it will cause reverse movement of the bracket. The bracket 48 projects from a carriage 51 (FIG. 2) and the latter has laterally projecting trunnions 52 which support rollers 53, the latter riding in the track grooves 54 of the track tube 27 (see also FIG. 5). Also rotatably supported on the carriage 51 are cam follower wheels 55 which engage opposite sides of the cam arm. 34, as shown in FIG. 2 and 6.

An electric motor 56 has its drive shaft 57 operating a grinding stone 58. Which stone is loosely surrounded by a guard strap 59, the latter having its ends connected to the carriage (see FIG. 2). Secured to the back of the motor casing is a baseplate 60 having projecting eye portions 61. An upright standard 62 on the carriage has laterally projecting eyes 63 and 64. Guide rods 65 are secured by setscrews to eyes of the standard 62 so that the motor and grinding stone are adjustably movable up and down on the guide rods 65. A shelf member 66 projecting from the carriage supports a ratchet wheel 67 which is rigidly mounted on an adjustment rod 68, the latter having a handle 69. The ratchet wheel coacts with a suitable dog on the shelf 66. The adjustment rod 68 has its lower portion in threaded engagement with a lug 70 projecting from the baseplate of the motor. Thus, when the handwheel 69 is turned in one direction or the other, the grinding stone will be raised or lowered on the carriage, the ratchet wheel providing for the holding of an adjusted position.

In FIGS. 4, and 6 is illustrated a cutter assembly of the type used in forage harvesters. It includes a suitable frame 71 having a cutting reel 72 therein, with a reel shaft 73 (see FIGS. 3 and 5) which is rotatably mounted in the frame as is customary. The cutting reel includes a suitable spider 74 supporting knives 75, usually six in number. The knives are usually helical, as is clear from FIG. 5, but the invention is applicable to reels having angled straight knives, such as the knives 75' of FIG. 8, in lieu of the helical knives. It is to be understood that in the claims the term angled," when used to refer to a cutter blade, means either a straight angled blade as shown in FIG. 8, or a helically angled blade as shown in FIGS. 4, 5 and 6. Each knife has a beveled cutting edge 76.

As shown in FIGS. 4, 5, and 6, the baseplate of the sharpener is suitably bolted to the top of the main cutting head, and it is to be noted from FIG. 5 that the forward edge of the baseplate 20 has hinge fittings 77 to which a hinged cover may be connected to close the knife chamber when the cutter is being used for cutting, and when the sharpener is swung to an inoperative position such as the position of FIG. 6.

When the sharpening assembly is being used the actuator arm and indexing hub assembly must be installed. An exploded view of this assembly is shown in FIG. 7. The actuator arm 78 projects from a ring 79 which is freely rotatable on the laterally extending portion of the shaft 73 of the cutting reel. This ring has circumferentially spaced indexing holes 80. The indexing hub 81 is the central portion of a disc 82. The hub is formed with internal splines 83 for coaction with the splines 84 of the cutter shaft 73 (see FIG. 3). Bolted to the inner face of the hub 81 is a washer 85 having a tongue 86 which fits in the keyway of the cutting reel shaft 73. The actuator arm ring is rotatable around the hub 81. Projecting from the outer face of the indexing hub is a. cylindrical housing 87 for an indexing pin 88. The indexing pin is slidable and rotatable in a bore of the housing 87 and has an inner end 89 adapted to engage one of the indexing holes 80 of the actuator arm ring 79 (FIG. 3), the pin being normally urged into engaging position by a spring 90 housed in an enlargement of the housing bore. The indexing pin 88 is fitted with a transverse pin 91 which coacts with a cam surface 92. When the indexing pin is rotated in a direction to rotate the transverse pin 91 in a clockwise direction or downwardly (referring to FIG. 3), this will withdraw the inner end 89 of the indexing pin from the indexing hole 80 against the urging of the spring 90. The spring assembly is held in position by a threaded plug 90.

OPERATION In use of the improved device on a forage harvester, the usual bolt-on section of the knife cover is removed before the baseplate 20 is bolted in the position shown in FIG. 4. The bolt-on cover section usually has a coacting hinged cover which can be removed and later connected to the hinge fittings 77 (shown in FIG. 5) after sharpening has been completed and before the harvester is put back into use.

The sharpener may be swung from the inoperative position of FIG. 6 to the operative starting position of FIG. 4 by exerting pressure in a counterclockwise direction on the carriage, which causes a rotation of the track tube 27.

Before installing the actuator arm and indexing hub it is necessary to remove the usual shear pin from the cutter cylinder shaft. The indexing hub and actuator arm are installed with the tongue 86 of the washer 85 mating with the usual keyway in the knife cylinder shaft 73. With the indexing pin 88 of the indexing hub engaged in one of the six indexing holes of the actuator arm ring, the splines of the hub should align with the splines of the shaft. In assembling, if the first hole does not cause alignment, the hub should be indexed to other positions until alignment is obtained. Thereafter the tie rod 93, which has one end pivotally connected to the actuator arm 78, is connected at its other end to the cam arm fitting 37 as at 94 (see FIGS. 1 and 5). This is a quick-connect ball-type fitting.

When the grinder is in the operative position of FIG. 4 the adjustment wheel 69 is manipulated to lower the grinding stone 58 until its end face contacts the bevel 76 on a knife 75 which is in properly indexed position.

With the operating crank 46 in place, it is turned slowly, the grinder motor being in operation. This will cause the grinding stone to travel in an axial direction from the position of FIG. 4 to the position of FIG. 5, due to the pull exerted by the endless chain 41 on the carriage bracket 48. It is desirable to turn the crank at a uniform speed fast enough to avoid burning of the knife edge. As the grinding stone travels from the position of FIG. 4 to the position of FIG. 5, the curvature of the cam arm 34 causes swinging movement of the cam arm on the pivot 35. This swinging movement acts through the tie rod 93 to cause movement of the actuator arm 78. Due to the fact that the hub is locked to the actuator arm ring by the indexing pin 88, swinging of the actuator arm 78 causes the cutting reel to be correspondingly rocked to compensate for the helical or angled disposition of the knife, thus maintaining the beveled portion 76 of the knife in the same relationship with the end of the grinding stone 58 regardless of the position of the grinding stone in its progression axially of the cutting reel. Since the angle of the knives is from right to left, clearance is needed for the right-hand tip of the knife edge as it meets the cutter bar of the cutting assembly. The right-hand end of the cam arm is so shaped as at 95 (FIG. 6) to automatically provide this clearance in grinding.

As cranking of the handle 46 continues, the pin 50 of FIG. 1, which connects the bracket 48 to the endless chain, travels down around an end sprocket to the lower stretch, sliding downwardly in the slot 49. This gives desirable time delay before the carriage reverses its direction of movement as cranking continues. The carriage will now start moving toward the right (referring to FIG. 5), and the shape of the cam bar now causes counterclockwise pivotal movement of the actuator arm 78. This pushes the hub in a counterclockwise direction to reverse the reel rocking so as to still keep the beveled portion 76 of the blades in proper relationship with the rotating grinding stone 58.

After the return stroke has been completed the indexing pin 88 is rotated in a clockwise direction (FIG. 4) or downward (FIG. 3) to release its end 89 from the indexing hole 80. The hub may then be rotated to bring the next knife into position for sharpening, the indexing pin 88 being allowed to snap into the new hole to hold the knife in indexed position for sharpening of this next blade.

After all of the knives have been sharpened, then the grinder head may be moved to the starting position of FIG. 4, the crank 46 removed, and the sharpening unit swung in a clockwise direction from the position of FIG. 4 to the inoperative position of FIG. 6, such swinging being permitted by the rotation of the track tube 27. The knife-casing cover which was heretofore removed can be then connected to the hinge fittings 77 and the cover swung to a closed position and suitably locked to form a guard over the knives. Before using the cutting reel for its intended purpose the tie rod 93 must be detached from the fitting 37 of the cam arm 34 and the indexing hub and actuator arm assembly must be removed from the shaft 73 of the cutting reel, the cutting reel shear pin being reinserted. The connection between the inner end of the tie rod 93 and the fitting 37 may be a readily detachable ball and socket type or any other detachable connection which permits adequate pivotal movement.

In the case of a forage harvester it is entirely practical to thereafter leave the sharpening unit in the inoperative position of FIG. 6 until sharpening again becomes necessary. Suitable means may be employed to prevent the unit from jouncing during field operation. If, however, it is desired to completely remove the sharpening unit, this may be done by removing the L-pins 22 and the capscrews 26, and lifting the sharpening unit off of the baseplate 20, leaving the latter in position for future use.

From the above it is clear that a relatively simple unit has been provided which may, if desired, be left in place on a forage harvester during field use. It is also clear that with the simple actuator and indexing hub assembly the sharpener may be quickly put back into sharpening position when required. In addition, the improved device provides means for easy manual indexing to bring a new knife into position for sharpening.

Various changes and modifications may be made without departing from the spirit of the invention, and all of such changes are contemplated as may come within the scope of the claims.

What we claim is:

1. In combination with a cutter assembly having a frame and having a rotatably mounted cutting reel provided with angled blades, each having a cutting edge, said reel having a shaft, a rotatable sharpening stone, means including a carriage supporting said stone on the frame for movement axially of the reel in a position to act on a blade thereof, an actuator disc rotatably mounted on said reel shaft, manually operable indexing means releasably locking said actuator disc to said reel shaft in a predetermined position of rotation to bring a blade of the reel into operative position with respect to the sharpening stone, and means between said carriage and actuator disc for causing automatic rocking movement of the reel in response to axial movement of the carriage so that all portions of the cutting edge of an angled blade are presented in proper edge sharpening relationship to the stone.

2. A combination as claimed in claim 1 in which the blades are helically angled.

3 A combination as claimed in claim 1 in which there is an indexing hub keyed to the reel shaft, and in which the manually operable indexing means comprises mechanism connected to the indexing hub for releasably locking the actuator disc in a predetermined position of rotation with respect to said hub.

4. A combination as claimed in claim 3 in which there is an indexing pin support connected to said hub, and in which there is an indexing pin movably mounted in said support, there being a circular series of holes in the actuator disc positioned to be selectively engaged by said indexing pin.

5. A combination as claimed in claim 4 in which there is means normally urging the indexing pin into engagement with one of the holes of the actuator disc and in which the indexing pin support has a cam surface, there being means on the indexing pin engageable with the cam surface when the pin is rotated for moving the pin to a disengaged position with respect to the actuator disc 6. A combination as claimed in claim 3 in which the actuator disc is rotatable around the indexing hub and has an actuator arm to which reel-rocking motion is transmitted from the carriage.

7. In a sharpener for the knives of a cutting reel, a frame adapted to be attached to a cutter assembly, an elongated track member rotatably mounted in said frame for rocking movement about an axis which is adapted to be disposed parallel with the axis of the cutting reel, longitudinal tracks on said elongated member, a carriage having wheels engaging said tracks to provide for support of the carriage and for movement of the carriage axially of the elongated track member, a sharpening stone supported on said carriage whereby said carriage and stone may be rocked with elongated track member into and out of operative position, and a cam arm having one end pivotally connected to said elongated track member near one end thereof for rocking movement therewith, in which there are cam followers on the carriage engageable with said cam arm, and in which there IS reelrocking mechanism pivotally connected to the other end of the cam arm.

8. A sharpener for the knives of a cutting reel as claimed in claim 7 in which said reel-rocking mechanism is readily disconnectable.

9. In a sharpener for the knives of a cutting reel, a frame adapted to be attached to a cutter assembly, an elongated track member rotatably mounted in said frame for rocking movement about an axis which is adapted to be disposed parallel with the axis of the cutting reel, longitudinal tracks on said elongated member, a carriage having wheels engaging said tracks to provide for support of the carriage and for movement of the carriage axially of the elongated track member, a sharpening stone supported on said carriage whereby said carriage and stone may be rocked with the elongated track member into and out of operative position, and sprocket wheel and endless chain mechanism for causing longitudinal movement of said carriage, there being shafts for said sprocket wheels which are supported transversely through the elongated track member.

10. In a sharpener for the knives of a cutting reel, a frame adapted to be attached to a cutter assembly, an elongated track member rotatably mounted in said frame for rocking movement about an axis which is adapted to be disposed parallel with the axis of the cutting reel, longitudinal tracks on said elongated member, a carriage having wheels engaging said tracks to provide for support of the carriage and for movement of the carriage axially of the elongated track member, and a sharpening stone supported on said carriage whereby said carriage and stone may be rocked with the elongated track member into and out of operative position, in which the elongated track member is rotatably supported between end plates, in which the means for attachment to the cutter assembly comprises a baseplate connectable with the cutter assembly, and in which there is means for detachably connecting the end plates to said baseplate.

11. In combination with a cutter assembly having a frame and having a rotatably mounted cutting reel provided with angled blades, each having a cutting edge, said reel having a shaft, a rotatable sharpening stone, means including a carriage supporting said stone on the frame for movement axially of the reel in a position to act on 'rilade thereof, an actuator disc rotatably mounted on said reel shaft, manually operable indexing means releasably locking said actuator disc to said reel shaft in a predetermined position of rotation to bring a blade of the reel into operative position with respect to the sharpening stone, and means between said carriage and actuator disc for causing automatic rocking movement of the reel in response to axial movement of the carriage so that all portions of the cutting edge of an angled blade are presented in proper edge-sharpening relationship to the stone, the supporting means for the carriage including a rotatably mounted tube having diametrically opposed tracks, and the carriage having wheels engaged with said tracks.

12. In combination with a cutter assembly having a frame and having a rotatably mounted cutting reel provided with angled blades, each having a cutting edge, said reel having a shaft, a rotatable sharpening stone, means including a carriage supporting said stone on the frame for movement axially of the reel in a position to act on a blade thereof, an actuator disc rotatably mounted on said reel shaft, indexing means releasably locking said actuator disc to said reel shaft in a predetermined position of rotation to bring a blade of the reel into operative position with respect to the sharpening stone, and means between said carriage and actuator disc for causing automatic rocking movement of the reel in response to axial movement of the carriage so that all portions of the cutting edge of an angled blade are presented in proper edge-sharpening relationship to the stone, said indexing means comprising an indexing hub keyed to the reel shaft, an indexing pin support connected to said hub, and an indexing pin movably mounted in said support, there being a circular series of holes in the actuator disc positioned to be selectively engaged by said indexing pin.

Claims

2. A combination as claimed in claim 1 in which the blades are helically angled. 3 A combination as claimed in claim 1 in which there is an indexing hub keyed to the reel shaft, and in which the manually operable indexing means comprises mechanism connected to the indexing hub for releasably locking the actuator disc in a predetermined position of rotation with respect to said hub.

5. A combination as claimed in claim 4 in which there is means normally urging the indexing pin into engagement with one of the holes of the actuator disc and in which the indexing pin support has a cam surface, there being means on the indexing pin engageable with the cam surface when the pin is rotated for moving the pin to a disengaged position with respect to the actuator disc

6. A combination as claimed in claim 3 in which the actuator disc is rotatable around the indexing hub and has an actuator arm to which reel-rocking motion is transmitted from the carriage.

7. In a sharpener for the knives of a cutting reel, a frame adapted to be attached to a cutter assembly, an elongated track member rotatably mounted in said frame for rocking movement about an axis which is adapted to be disposed parallel with the axis of the cutting reel, longitudinal tracks on said elongated member, a carriage having wheels engaging said tracks to provide for support of the carriage and for movement of the carriage axially of the elongated track member, a sharpening stone supported on said carriage whereby said carriage and stone may be rocked with elongated track member into and out of operative position, and a cam arm having one end pivotally connected to said elongated track member near one end thereof for rocking movement therewith, in which there are cam followers on the carriage engageable with said cam arm, and in which there is reel-rocking mechanism pivotally connected to the other end of the cam arm.

11. In combination with a cutter assembly having a frame and having a rotatably mounted cutting reel providEd with angled blades, each having a cutting edge, said reel having a shaft, a rotatable sharpening stone, means including a carriage supporting said stone on the frame for movement axially of the reel in a position to act on a blade thereof, an actuator disc rotatably mounted on said reel shaft, manually operable indexing means releasably locking said actuator disc to said reel shaft in a predetermined position of rotation to bring a blade of the reel into operative position with respect to the sharpening stone, and means between said carriage and actuator disc for causing automatic rocking movement of the reel in response to axial movement of the carriage so that all portions of the cutting edge of an angled blade are presented in proper edge-sharpening relationship to the stone, the supporting means for the carriage including a rotatably mounted tube having diametrically opposed tracks, and the carriage having wheels engaged with said tracks.