US3678668A

US3678668A - Mower blade and connection therefor

Info

Publication number: US3678668A
Application number: US75347A
Authority: US
Inventors: Carl W Mott
Original assignee: Mott Metallurgical Corp
Current assignee: Mott Metallurgical Corp
Priority date: 1970-09-25
Filing date: 1970-09-25
Publication date: 1972-07-25
Anticipated expiration: 1989-07-25
Also published as: BE777376A

Abstract

A connection for attaching a mower blade directly to a lug provided on a mower shaft. The blade comprises a pair of resilient fingers cooperating with an opening provided in the lug. The opening in the lug may be circular or non-circular having a long and a short dimension. The long dimension of the non-circular opening is such that when the blade is turned to the long dimension and the fingers are compressed, the fingers will pass through the opening. The short dimension is such that when the blade is turned to such short dimension, the blade cannot be compressed sufficiently to be removed from the opening of the lug. The blade may be removed from the circular opening, regardless of the position of the blade in the opening, by compressing the blade. To connect the blade to the lug of the shaft, the fingers of the blade are gripped in a tool and compressed, and the compressed fingers are then inserted into the opening in the lug. Notches provided in the edges of the fingers are aligned with the margin of the opening in the lug, and the fingers are then released so that the notches loosely engage the lug to retain the blade on the lug. By a converse operation the blade may be removed from the lug.

Description

[ 51 July 25,1972

626,954 9/1961 Canada........... Great Britain..........................

[54] MOWER BLADE AND CONNECTION THEREFOR Primary Examiner--Russell R. Kinsey Attorney-Hibben, Noyes & Bicknell [72] Inventor: Carl W. Mott, Lake Ozark, Mo.

[73] Assignee: Mott Corporation, LaGrange, Ill.

[22] Filed: Sept. 25, 1970 ABSTRACT A connection for attaching a mower blade directly to a lug [21] Appl. No.: 75,347

provided on a mower shaft. The blade comprises a pair of resilient fingers cooperating with an opening provided in the Related U.S. Application Data [63] Continuation-impart of Ser. No. 54,246, July 13,

lug. The opening in the lug may be circular or non-circular 1970, abandone having a long and a short dimension. The long dimension of the non-circular opening is such that when the blade is turned 52 U S C] 1 to the long dimension and the fingers are compressed, the fing will p through the p g The short dimension is such that when the blade is turned to such short dimension,

[51] Int. Cl. [58] Field of the blade cannot be compressed sufficiently to be removed from the opening of the lug. The blade may be removed from References Cited the circular opening, regardless of the position of the blade in UNITED STATES PATENTS the opening, by compressing the blade. To connect the blade to the lug of the shaft, the fingers of the blade are gripped in a tool and compressed, and the compressed fingers are then inserted into the opening in the lug. Notches provided in the edges of the fingers are aligned with the margin of the opening 56/294 in the lug, and the fingers are then released so that the notches loosely engage the lug to retain the blade on the lug. By a converse operation the blade may be removed from the lug.

em n m da eh mkn MBRF 0689 7656 9999 1111 l/l/ 47 9 0 57 0570 3 5 05 0666 3323 FOREIGN PATENTS OR APPLlCATlONS 1,127,515 9/1968 Great Britain...........................56/294 17 Claims, 9 Drawing Figures Patented July 25, 1972 3,678,668

2 Sheets-Sheet 2 fn/venib r.-- Ccvrl Wffait,

3 M, W, J W @5.

MOWER BLADE AND CONNECTION THEREFOR CROSS REFERENCE TO RELATED CASE This application is a continuation-in-part of my copending U.S. application Ser. No. 54,246 now abandoned, filed July 13, 1970.

This invention relates to mowers, and more particularly to a novel blade connection for directly attaching a blade to a mower.

The present invention relates to a mower of the type shown in my prior U.S. Pat. No. 2,71 1,067 issued June 21, 2955, and includes a horizontal rotatably driven shaft extending transversely of the direction of travel. Mounted on the shaft are a plurality of axially spaced lugs extending radially therefrom, to which are loosely secured a plurality of blades or knives, the latter being adapted toextend outwardly from the lugs by virtue of centrifugal force.

Heretofore, blades for mowers of the type described were attached or secured to the lugs by intermediate fasteners or clips. Although such blade connections worked satisfactorily, additional parts were needed to connect the blades to the lugs.

The present invention has eliminated the need for such additional parts by directly connecting the blade member to the lug member of the mower shaft. To this end, a resilient elastic connecting means is provided on the members to connect the blade to the lug. The blade may be quickly and easily installed, or disconnected, from the lug by deforming the resilient connecting means and removing the blade from the lug.

Accordingly, it is the general object of the present invention to provide an improved construction for connecting a blade to a lug of a mower shaft which is simple and inexpensive to manufacture.

Other objects and advantages of the invention will become apparent from the following description and accompanying drawings in which:

FIG. I is a fragmentary front elevational view of a mower shaft incorporating a first embodiment of the present inventron;

FIG. 2 is an enlarged cross-sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is a perspective view of a portion of the shaft shown in FIG. I and a blade being connected to the lug;

FIG. 4 is a perspective view of the blade of the first embodiment;

FIG. 5 is a fragmentary perspective view of an alternate blade construction;

FIG. 6 is an enlarged cross-sectional view of the rotating parts of a mower, having an alternative lug construction;

FIG. 7 is a cross-sectional view taken on the line 77 of FIG. 6;

FIG. 8 is a cross-sectional view taken on the line 88 of FIG. 6; and

FIG. 9 is a cross-sectional view taken on the line 99 of FIG. 6.

In FIG. I, a horizontal shaft, indicated at 10, of a mower of the type with which the blade connection of the present invention is to be used, is illustrated. The ends of the shaft 10 are in a housing (not shown) having bearing structure ll for supporting the shaft. When the mower is in use, the shaft 10 is rotated about its axis, as for example by a pulley and belt arrangement connected to an engine.

The shaft 10 is preferably non-circular, in this instance square in cross section and of a length depending on the mower size.

On the shaft 10 at spaced intervals are located lug members 12 to which blade members 14 are directly connected. While the lugs may be secured integrally to the shaft as by welding, the lugs 12 are preferably removably secured to the shaft to accommodate different sized blades and to facilitate replacement of damaged or worn lugs 12. The lugs 12 constitute the opposite end portions of a flat elongated strip I6 having at its center a square opening 18 to accommodate the square shaft I0. The adjacent strips 16 are displaced 90 apart. Each strip 16 may be slid into position on the shaft 10 and is axially spaced from adjacent strips 16 by tubular spacers 20 which are also slidable onto the shaft 10. The spacers 20 abut the strip 16 to locate the lugs 12 along the shaft. The spacers and lugs are held in abutment on the shaft by means located at the ends of the shaft. In the present instance, the spacer at one end of the shafl abuts a bearing 11 in the housing supporting the shaft, and at the other end, spring means in the form of a coil spring 21 is mounted on the shaft between the bearing 11 at that end of the shaft and the end strip 16.

At the outer ends of the lug members 12, and on the blade members 14 are located co-operating connecting means. The co-operating connecting means comprises resilient means one one of said members, and an opening provided in the other of said members to receive said resilient means. While the resilient means can be on the lug member and the opening provided in the blade member, in this instance, the co-operating connecting means comprises a circular opening 24 in the other end of the lug and resilient fingers formed on the blade 14. Each blade 14 comprises an elongated member having cutting edges and resilient fingers to connect the blade to the lug. As is shown in FIG. 4 the blade is formed from a metal strip and has a center portion 28 and two

bent ends

30 and 32. One end 30 of the blade 14 is sharpened so as to provide two cutting edges 26 and 27. Should one edge, for example edge 26, become worn the other edge 27 may be used by reversing a blade 14 on its associated lug 12, as is shown in dashed lines in FIG. 1. When a blade is reversed in this manner, the blade on the opposite lug should also be reversed so that the swath cut by the respective blades will be complete and the dynamic balance maintained End 30 of the blade 14 is bent with respect to the center portion 28 of the blade generally at different angles depending on the length of the blade. The other end 32 of the blade, which is connected to the lug 12, is also bent with respect to the center portion 28 at an angle which will shed cuttings when rotated at high speed. Different length blades would require different angles between the bent end 32 and center portion 28 thereof in order to assure shedding of cuttings.

While the resilient fingers could have been provided on the lug, in this instance the resilient fingers 34 are formed on the blade by bifurcating the latter. The blade 14 is made of tempered steel, and the fingers 34 may be compressed until their ends abut and will upon release return to their normal position. The fingers 34 are formed by cutting a slot 36 into the end 32 of the blade 14. In this instance, the slot 36 has been carried down into the center portion 28 to permit each finger 34 to distort by twisting and to decrease the force necessary to compress the fingers. As is shown in FIG. 4, the inner end of the slot 36 is rounded to reduce the stress concentration at that point. The outer edges 42 of the fingers 34 are parallel and have a width greater than the diameter of the opening 24 so that the end 32 of the blade 14 when uncompressed will not pass through the opening 24. The outer edges of the blade 14, having notches 43 therein, may be brought toward each other by compressing the fingers 34 with a tool, preferably in the form of a pliers 44 shown in FIG. 3. The pliers 44 have

jaws

46 and 48 connected to

handles

50 and 52 such that squeezing the

handles

50 and 52 will move the

jaws

46 and 48 toward each other to compress the fingers 34 together. A conventional pliers could also be used to compress the fingers 34.

The blade 14 may be installed in the lug 12 by the following operations: the fingers 34 of the blade 14 are compressed until the end 32 of the blade can pass through the opening 24. Depending on the width and shape of the blade I4 it may be necessary to first cock the blade so that one of the notches 43 first engages one side of the opening 24. Tips 54 on the fingers 34, which help align the end 32 of the blade with the opening 24, may then be inserted into the opening 24 until the notches 43 are adjacent the margin 58 of the lug 12. If conventional pliers are used, the tips 54 of the fingers 34 are first inserted through the opening 24 and then the tips may be gripped with the pliers to compress the fingers. The fingers 34 are then shifted through the opening 24 until the notches 43 are aligned with the margin 58 of the opening 24. The pliers are then released and the fingers 34 spring back so that the notches 43 engage the margin 58 of the opening 24. The blade may be removed from the lug by reversing these operations. With the circular opening 24 the blade may be installed or removed from the opening regardless of the position of the end 32 of the blade in the opening.

In the form of blade, indicated at 60, shown in FIG. 5, the outer end of the blade is bent and sharpened in the same manner as the end 30 of the blade 14. The inner end, indicated at 61, of the blade 60 is also similar to the inner end of the blade 14 and is provided with a slot 66 terminating in the central portion, indicated at 62, of the blade and defining a pair of fingers 67. The fingers 67 thus extend from the inner end 61 into the central portion 62 of the blade 60. A pair of notches 68 are formed in the outer margins of the fingers 67 for engaging the margin 58 of an opening 24 in the lug 12.

- The blade 60 differs from the blade 14 in that the tips 54 of the blade 14 are omitted from the fingers 67 of the blade 60. Such construction facilitates shifting of the fingers 67 into and out of the opening 24 in the lug and results in a more economical construction in that the total length of the blade 60 is shortened. To this end, the outer ends, indicated at 69, of the fingers 67 are curved.

A pair of either form of blade when mounted on the lugs 12 on each strip 16 is in dynamic balance. The lugs 12 on each strip 16 are located in the same plane and are transverse to the axis of the shaft 10. The blades are relatively movable with respect to the lugs 12 in a plane including the axis of the shaft so that upon rotation of the shaft the centers of gravity of the blades are positioned to dynamically balance the blades. The width of the notches is such as to permit the above-mentioned movement.

The blades are also free to move in a plane transverse to the axis of the shaft so that the blades will pivot on the lug in such plane should the blades strike a rock or similar object.

The form of lug, indicated at 70 in FIGS. 6 through 9 is the same as the lug 12, except for the opening therein hereinafter described. Thus, the lugs 70 constitute the opposite end portions of a flat, elongated strip 65 which is secured to a mower shaft 71 in the same manner as the strip 16 of the previous embodiment, and a blade, in this instance the blade 60 previously described, is connected to each lug 70. An opening 72 is provided at the outer end of each lug 70 for receiving and retaining a blade 60.

Each opening 72 is non-circular to facilitate installation of a blade and to improve retention of the blade. Preferably, the opening 72 is pear-shaped and has long and short dimensions, respectively indicated at 73 and 74 in the opening 72 in the upper lug 70 in FIG. 6. Each opening 72 is arranged in the lug 70 so that the long dimension 73 thereof lies substantially on or parallel to a shaft radius with the short dimension 74 transverse to the long dimension 73. In addition, each opening 72 is arranged so that the short dimension 74 thereof is positioned closer to the radially outer end of the long dimension 73 than to the radially inner end of the long dimension.

The procedure for installing a blade in an opening 72 is generally similar to that previously described. Thus, as shown in FIGS. 6 and 7, the connecting means or fingers 67 of the blade 60 lie in a plane and are compressed as by the jaws of a pair of pliers 44, thus reducing the width of the inner end 61 of the blade. The blade 60 is then cocked turned or slightly so that the plane of the connecting means is aligned with the long dimension, as shown in FIGS. 6 and 7, and the blade 60 is then inserted at the long dimension of the opening 72 with one of the notches 68 engaging the margin of the opening 72 at its long dimension. The blade is then straightened in the opening 72 and is released from the pliers, both notches 68 then engaging the margin of the opening 72. The long dimension may be slightly shorter than the width of the blade when uncompressed so that the blade will still be retained even at the long dimension of the opening 72 when the blade is released.

During operation of the mower, rotation of the shaft and centrifugal force will cause the blades to extend in a generally radial direction. The inner end 61 of each blade 60, in this instance, will rotate to a position which generally coincides with the short dimension of the opening 72. The blade contacts the margin of the opening 72 adjacent the short dimension which is preferably slightly larger than the width of the blade between the bottoms of the notches 68. Thus, the blade is free to pivot in the opening 72. Since the short dimension of the opening 72 is less than the width of the end 61 of the blade when compressed, the blade cannot become disconnected even if it should strike a solid object while rotating and be compressed. Should the blade turn in the opening to the long dimension, the blade will still be retained on the lug since the fingers of the blade have to be compressed to remove the blade.

It is apparent that a novel blade connection for a mower shaft having lugs has been provided wherein the blades have resilient connecting means to connect the blade to the lug of the shaft.

1 claim:

1. ln a mower having a shaft, the combination of a lug member adapted to be secured to said shaft and extending generally radially therefrom, and a blade member, one of said members having means resiliently displaceable for removably engaging with the other of said members to connect said members.

2. The combination of claim 1, wherein said resiliently displaceable means comprises a pair of fingers on one of said members, the other of said members having an opening to removably receive said fingers.

3. The combination of claim 2, wherein said opening is noncircular and has a long and a short dimension, said short dimension being transverse to a radius of said shaft, and said long dimension being generally parallel to said radius.

4. The combination of claim 3, wherein said opening is pear-shaped.

5. The combination of claim 2, wherein said fingers are formed on said blade, and said opening is formed in said lug.

6. The combination of claim 2, wherein at least one of said fingers has a notch for engaging the margin of said opening.

7. The combination of claim 2, wherein said opening is smaller than the width of said fingers when in their normal position, said fingers being compressible toward each other for insertion into said opening, each of said fingers having a notch in its outer edge for engaging the margin of said opening when said fingers are inserted in said opening and are released from compression.

8. A mower blade adapted to be connected to a mower shaft having an opening associated therewith, said blade having resilient means for removably engaging a margin of said opening.

9. A mower blade as in claim 8, wherein one end of said blade is sharpened to provide a cutting edge and the other end of said blade is slotted endwise of the blade to form a pair of fingers constituting said resilient means.

10. A mower blade adapted to be connected to a lug on a mower shaft, said blade having resilient means adapted to removably engage a margin of an opening in said lug, said resilient means being bifurcated to form a pair of parallel compressible fingers each having a notch in the outer edge thereof for engagement with said margin of said opening in said lug.

11. The combination of claim 1, further comprising a shaft, a plurality of said lugs mounted on said shaft in spaced relation to each other, a plurality of spacers mounted on said shaft between said lugs, said shaft having at one end an abutment against which one of said spacers abuts, and a coil spring mounted on the other end of said shaft and abutting a lug adjacent said other end to hold said lugs and spacers in assembled relation on said shaft.

12. in a mower having a shaft, the combination of opposed lug members located in the same plane and transverse to the axis of said shaft and adapted to be secured to said shaft and extending generally radially therefrom, and opposed blade members directly connected to said lug members, said blade members being movable on said lug members in a plane including the axis of said shaft.

13. In a mower, a lug adapted to be connected to a shaft of 5 the mower and at its outer end to a blade of the mower, said lug being an elongated metal strip having a nomcircular opening at said outer end to receive said blade, said opening having a long dimension and a short dimension, said blade having connecting means which when compressed and turned so that the plane of the connecting means is aligned with said long dimension is insertable into said opening.

14. A mower blade as in claim 8, wherein said resilient means is bifurcated to form at least one displaceable finger for engagement with said margin of said opening.

15. A mower blade as in claim 8, wherein said resilient means is displaceable from a normal position to a second position to permit installation of said blade on and removal of said blade from said shaft and springing back to substantially said normal position to retain said blade on said shaft.

16. The mower blade of claim 11, wherein one end of said blade is sharpened to provide a cutting edge and the other end of said blade is slotted endwise of the blade to form said fingets.

17. The mower blade of claim 11, wherein said fingers when in their normal position, are wider than the opening, said fingers being compressible toward each other to a width smaller than the opening for insertion into the opening.

zg gg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,678,668 D d July 25 1972 Inventofls) CARL W. MOTT It is certified that error appears in the aboveidentified patent and that said Letters Patent are hereby corrected as shown below: 1

Col. 1, line 8, "2955" should read --l;955-. C01. 2, lines 13 and 14, "one One" should read ---On one--. Col. 2, line is, "other" should read --outer. Col. 2, line 32, insert a per od after "maintained". C01. 3, line 64, "cocked turned or slightly should read turned or cocked slightly.

Signed and sealed this 1st day of May 1973.

(SEAL) Attest:

EDZIARD M. FLETCHER, J'E. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents

Claims

1. In a mower having a shaft, the combination of a lug member adapted to be secured to said shaft and extending generally radially therefrom, and a blade member, one of said members having means resiliently displaceable for removably engaging with the other of said members to connect said members.

3. The combination of claim 2, wherein said opening is non-circular and has a long and a short dimension, said short dimension being transverse to a radius of said shaft, and said long dimension being generally parallel to said radius.

4. The combination of claim 3, wherein said opening is pear-shaped.

13. In a mower, a lug adapted to be connected to a shaft of the mower and at its outer end to a blade of the mower, said lug being an elongated metal strip having a non-circular opening at said outer end to receive said blade, said opening having a long dimension and a short dimension, said blade having connecting means which when compressed and turned so that the plane of the connecting means is aligned with said long dimension is insertable into said opening.

16. The mower blade of claim 11, wherein one end of said blade is sharpened to provide a cutting edge and the other end of said blade is slotted endwise of the blade to form said fingers.