US2715797A

US2715797A - Sickle grinder

Info

Publication number: US2715797A
Application number: US343289A
Authority: US
Inventors: Robert W Fuller
Original assignee: J F COLVARD
Current assignee: J F COLVARD
Priority date: 1953-03-19
Filing date: 1953-03-19
Publication date: 1955-08-23
Anticipated expiration: 1972-08-23

Description

Aug. 23, 1955 R. w. FULLER 2,715,797

SICKLE GRINDER Filed March 19, 1953 2 Sheets-Sheet 1 55 Robert W. Fuller 56 2 U) o I INVfNTOR.

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Aug. 23, 1955 l R. w. FULLER SICKLE GRINDER 2 Sheets-Sheet 2 Filed March 19, 1953 Robert M. Fuller INVENTOR. Q0132...

By M7:

United States Patent SICKLE GRINDER Robert W. Fuller, Durham, N. C., assignor of fifty per cent to J. F. Colvard, Durham, N. C.

Application March 19, 1953, Serial No. 343,289

2 Claims. (11. 51-33 This invention relates to the class of machine tools and more particularly to a device adapted to restore the cutting edges of sickle blades and like equipment.

The primary object of this invention is to grind the cutting edges of sickle blades and the like to a required degree of sharpness.

The construction of this invention features means for resiliently mounting a sickle blade within a sickle blade holder. Other means resiliently pivotally mount a grinding stone so that it may be brought into engagement with the cutting edges of the sickle blade. noted that the resilient mounting of the sickle blade holder provides means for determining the amount of pres sure applied on the sickle blade by the grinding stone. There is provided a combined track and index bar on which the carriage carrying the grinding stone moves relative to the sickle blade holder. An indexing arm is pivotally attached to the carriage and is adapted to engage the index bar to align the grinding stone with the successive cutting edges forming the teeth.

Still further objects of the invention reside in the provision of a sickle grinder that is strong and durable, simple in construction and manufacture, assembled from a minimum number of parts, and which is capable of readily and easily restoring the cutting edges of the teeth of a sickle blade while being relatively inexpensive to produce.

These, together with the various ancillary objects and features of the invention which will become apparent as the following description proceeds, are attained by this sickle blade grinder, a preferred embodiment of which has been illustrated in the accompanying drawings, by way of example only, wherein:

Figure 1 is a top plan view of the device comprising the present invention;

Figure 2 is a front elevational view of a sickle grinder constructed in accordance with the principles of the present invention, illustrating in greatest detail the relative relationship between the notches in the index bar and the teeth of the sickle blade to be worked upon;

Figure 3 is a sectional detail view as taken along the plane of line 3-3 in Figure 1;

Figure 4 is a vertical sectional view as taken along the plane of line 4-4 in Figure 1;

Figure 5 is a sectional detail view illustrating the manner in which the grinding stone resiliently engages a sickle blade carried by the sickle blade holder; and,

Figure 6 is a perspective detail illustrating the construction of the sickle blade holder.

With continuing reference to the accompanying drawings wherein like reference numerals designate similar parts throughout the various views, reference numeral 10 generally designates a rectangular angle iron frame which, together with the legs 12, forms a stand on which the other elements of the invention are adapted to be placed. Secured to the frame 10 are a pair of bearing supports 14 and 16 in which a shaft 18 is journalled. The shaft 18 has welded thereto a sickle blade holder 20 which includes a It is to be length of angle bar 22 having a plurality of clamp members 24 attached thereto and extending perpendicularly to one of the flanges of the angle bar 22 while extending parallel to the other flange thereof. A plurality of threaded apertures 26 are provided in the angle bar 22 and threaded rods 28 having handles 30 are threadedly engaged in the apertures 26 and adapted to hold a sickle bar as indicated at 32 between the heads 34 of the threaded members 28 and the clamp members 24. Also welded to the shaft 18 is an end seating block 36 in which the end of the sickle blade 32 can be seated so as to align the sickle blade 32. The shaft 18 has splined or otherwise secured thereto

crank arms

38 and 40 which have

springs

42 and 44 depending therefrom.

Secured to the frame 10 are a pair of tracks 46 and 43 which are preferably formed from two lengths of angle iron. The track 48 is provided with a plurality of spaced notches 50 in the vertical flange thereof. The notches 50 are adapted to coincide with the recesses between the teeth of the sickle blade 32 when the sickle blade 32 is installed in the sickle blade holder 20. A carriage 52 having a platform 54' from which legs 56 depend carries rollers 58 which ride within the

tracks

46 and 48. There is mounted on the platform 54 an electric motor 60 which drives by means of an endless belt 62 a pulley wheel 64 mounted on a shaft 66 journalled in

bearing supports

68 and 70 which are also mounted on the platform 54. Another pulley wheel 72 is carried by the shaft 66 and drives by means of the endless belts 74 a pulley wheel 76 mounted on the shaft 78. Rotatably mounted on the shaft 66 is a yoke 80 of substantially H- shape within which the shaft 78 is rotatably mounted. Fixed to the shaft 78 is a grinding stone 84 of a shape corresponding to two truncated conical segments joined at their bases. An operating handle 85 is provided for rotating the yoke 80 and hence the grinding stone 84 downwardly and into engagement with the cutting edges of the sickle blade 32.

In operation, a sickle blade of any convenient length or size is inserted and clamped in place in the sickle blade holder 22, the end of the sickle blade 32 being seated in the end block 36 thus automatically aligning the recesses between the teeth of the sickle blade 32 with the notches 50. Then, the carriage 52 can be moved along the tracks to a desired position at which time a carriage indexing arm 86 pivotally mounted to a member 88 forming a part of the carriage 52 is engaged within a selected notch 50. It is to be noted that the

springs

42 and 44 are also secured to the index bar or track 48. The sickle blade 32 is resiliently carried by the sickle blade holder 20 and when the yoke 80 is rotated downwardly by actuating the operating handle 85. Therefore, the

qualities

42 and 44 determine the maximum amount of pressure available between the grinding stone 84 and a blade 32. It is to be noted that the spring 82 will return the grinder 84 to its initial position, as is shown in Figure 4, the stop 92 attached to the yoke 80 limiting the position of the grinding stone 84 when released.

Since from the foregoing, the construction and advantages of this grinder are readily apparent, further description is believed to be unnecessary.

However, since numerous modifications will readily occur to those skilled in the art after a consideration of the foregoing specification and accompanying drawings, it is not intended to limit the invention to the precise embodiment shown and described, but all suitable modifications and equivalents may be readily resorted to which fall within the scope of the appended claims.

What is claimed as new is as follows:

1. A sickle grinder comprising a stand, a shaft rotatably supported on said stand, a sickle blade holder secured to said shaft, resilient means engaging said shaft for holding said sickle blade holder in a normal position,'a pair of spaced carriage tracks on said stand, one of said tracks having a plurality of notches therein forming an index bar, a carriage movably mounted on said tracks, a grinding stone pivotally mounted on said carriage,-means for driving said grinding stone carried by said carriage, an operating handle for pivoting said grinding stone into resilient grinding engagement with a sickle blade carried by said sickle blade holder, and a carriage indexing arm pivotally attached to said carriage selectively engaged in index notches in said index bar to correspond to the teeth in a sickle blade, said resilient means including an arm attached to said sickle blade holder, and a spring attached to said arm and said index bar. I

2..A sickle grinder comprising a stand, a shaft rotat ably supported on said stand, a sickle blade holder secured to said shaft, resilient means engaging said shaft for holding said sickle blade holder in a normal position, a pair, of spaced carriage tracks on said stand, one of said tracks having a plurality of notches therein forming an index bar, a carriage movably mounted on said 7 tracks, a grinding stone pivotally mounted on said can 4 riage, means for driving said grinding stone carried by said carriage, an operating handle for pivoting said grinding stone into resilient grinding engagement with a sickle blade carried by said sickle blade holder, and a carriage indexing arm pivotally attached to said carriage selectively engaged in index notches in said index 7 bar to correspond to the teethin a sickle blade, said re- 'silient means including an arm attached to said sickle blade holder, and a spring attached to said arm and said index bar, and resilient means for urging said grinding stone into a normal position away from said sickle blade holder, said sickle blade holder having a plurality of spaced clamps for lockinglj holding a sickle blade in said holder.

Webb'er Jan. 29, 1952