US2271354A

US2271354A - Plow disk

Info

Publication number: US2271354A
Application number: US317868A
Authority: US
Inventors: Carl G Strandlund
Original assignee: Deere and Co
Current assignee: Deere and Co
Priority date: 1940-02-08
Filing date: 1940-02-08
Publication date: 1942-01-27
Anticipated expiration: 1959-01-27

Description

C.'G. STRANDLUND 2,271,354

' PLOW DISK Filed Feb. 8, 1940 I I INVENTOR: 0ARL 6: STRA/VOL ND.

Patented Jan. 27, 1942 OFFICE PLOW DISK Carl G. Strandlund, Moline, Ill., assignor t Deere & Company, Moline, 111.,

Illinois a corporation of Application February a, 1940, Serial No. 317,868

12 Claims.

The present invention relates generally to disk plows and is more particularly concerned with plow disks having removable sectional cutting segments.

The object and general nature of the present invention is the provision of a plow disk of this character wherein the center'disk section is made of tough resilient material, such as low carbon semi-soft steel which is relatively inexpensive, and wherein the cutting edge of the disk comprises a detachable peripheral section formed of relatively hard wear-resistant material, such as alloy steel, which is relatively expensive. the alloy steel peripheral section takes the brunt of the wear while the center disk section possesses the required toughness and strength to absorb shocks and the like.

A further feature of this invention is the provision of a plow disk in which the center disk section is dished and has a substantially continuous concave surface and carries at its peripheral portion a detachable peripheral section, preferably in the form of a plurality of mating segments, which is also dished and is secured to the center disk section so that the inner surface of the detachable peripheral section is substantially a continuation of the concave surface of the center disk section. It is quite important, especially in a plow disk, to have the inner or working face of the disk a smooth and continuous surface, and

it is therefore an additional feature of the present invention to provide the center disk section with an offset peripheral portion which has the required amount of offset to receive the detachable peripheral hardened section so that the inner surface of the latter can be continuous with the inner surface of the tough and strong center disk section. V

More specifically, it is a further feature of this invention to provide a plow disk having a tough center disk section and a detachable peripheral section in the formof a plurality of segments, dished to conform to the curvature of'the center disk section and each having an outer sharpened edge, the corners of which are cut back so as to provide notches. These notches have a two-fold advantage. In the first place, cutting away the outer corners of each segment serves to remove some of the material from the segment, especial- 1y the thinner portions thereof, which is likely to break off in service. Preferably, the amount removed is sufficient to extend back into the thicker part of the segment. In the second place, when the segments are assembled, notches are Thus,

when working in trashy soil. Further, eliminatingthe possibility of cracking of the segments at the sharpened edge thereof is a special advanments, which are formed of hard metal, such as alloy steel, are also of substantially uniform thickness except, of course, the cutting edge, which is thinner. Y

These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description, taken in conjunction with the accompanying drawing illustrating apreferred structure.

In the drawing:

Figure 1 is a face view of a plow disk in which the principles of the present invention have been incorporated;

Figure 2 is a sectional view taken at an enlarged scale along the line 22 of Figure 1; and

Figure 3 is a fragmentary perspective View of one notched corner, of one of the peripheral segments.

Referring now to the drawing, the reference numeral I indicates the plow disk in its entirety, and as shown the plow disk l includes a center disk section 2 formed of boiler plate or other material, such as, for example, tough resilient semiso'ft steel. As best shown in Figure 2, the center section 2 is of substantially uniform thickness and includes an offset section 4, the thickness of wh ch is substantially the same as the thickness.

of the main body of the center disk 2. 'Ihelatter carries a plurality of bolts 5, the heads of which are substantially flush with the inner surface ii of the center dis-k section The bolts fi'form a part of the center disk section Hand Serve as means whereby the disk may be connected with a;-suitable supporting bearing structure (not shown) As will be clear from Figure'2, the surface 6 of the center disk section is concave; likewise,-the inner surface 6a of the offset portion 4 lies in a concave surface which is generally'parallel,-or concentric, with respect to the concave sur- -formed which causev thedisk to operate better s; face 6.' The offset part '4 of the central disk 2 is joined to the main body portion thereof by a curved section I.

The outer peripheral section of the disk I, as indicated by reference numeral 8, consists of a plurality of segments 9 which, taken together, constitute the peripheral section 8 aforesaid. Each segment 9 is dished and is formed of bar stock, preferably of alloy steel or other exceedingly hard wear-resistant material. As best shown in Figure 2, each segment is of substantially uniform thickness and the dished surface, indicated at 90, of each segment conforms in concavity to the concave surface 6. To this end, the amount of offset of the surface 6a relative to the surface 6 corresponds practically exactly to the thickness of the segments 9, whereby the inner surface of the segments form a continuationof the concave surface 6. The radially inner edge of each segment 9 is beveled, as at I9, to fit snugly and smoothly against the curved portion 1 of the center disk section 2. Thus, the entire working face of the disk I is smooth and continuous, scours easily, and otherwise serves the purpose for which it is intended. Each segment 9 is secured by one or more bolts II to the associated offset 4 of the center disk 2. In order to secure and maintain the continuous surface'mentioned above, the heads of the bolts II are countersunk, as shown in Figure 2. The radially outer edge of each segment 9 is beveled off by plating, preferably in two steps, as shown at I2a (see Figure 3) and I22), the first being relatively short and the second extending radially inwardly to the point I2c. Radially inwardly from this point each segment 9 is of uniform thickness except for the inner beveled part If]. The beveled part I2a serves to form a sharpened edge I3, and the edges I3 of the various segments 9 form the cutting edge of the disk I.

As best shown in Figures 1 and 3, the radially outer corner of each segment 9 is cut away, as at I5. The amount of material removed from the corners of each segment 9 is not great, but the removed portions extend from the sharp cutting edge back through the part of the segment 9 of relatively small thickness almost to the point I20 where the segment is of uniform thickness. This is an important advantage of the present invention. First, it will be remembered that the segments 9 are formed of hard material, and hence where the peripheral section of the disk is in the form of a plurality of segments with square corners, as shown at I3a (Figure 3) there is some likelihood that the corners of the various segments might break off in service, especially since at the corners of the sharpened edge I3 the thickness of the segment is small. According to the present invention, I cut off this portion of each segment, bringing the'corner of the segment al- 'most as far back as the point I20 so as to reach the thicker portions of the segment. The angle a (Figure 3) between the faceof the corner bevel I5 and the cutting edge .-I3 is sufficiently large that there is nomaterial likelihood of the point [31) becoming fractured or breaking off. Thus, this construction eliminates to a large extent the danger of small cracks developing at the corners of the segment and extending back into the main body of the segment, and since I thus prevent the small cracks from starting, the segments of my plow disk are especially long lived.

From Figure 1 it will be seen that the bolts I I fasten the segments 9 in position on the offset portion 450 that the edges of the segments 9 are in substantial contact, except, of course, at the beveled corners I5 where the latter form notches in the cutting edge of the disk. These notches, at I5, have an additional function, other than preventing the segments from breaking off at the corner and/or cracks developing in the disks. The notches at I5 cause the disk I to operate better under trashy conditions where ordinary disks tend to slide rather than roll or rotate. The notches at I5 cause the disk to engage the trash, or other ground surface, and to continue rolling, which gives the circular cutting edges I3 a chance to cut through the trash very effectively and covering it, where ordinary disks would tend to slide and merely push the trash ahead.

The number of segments 9 employed may vary as desired, or according to the number of notches I5 which it is deemed necessary to have. The segments 9, being in contact at their edges except for the notches I5, are rigid against backward deflection since, generally speaking, they serve as an arch. Like the center disk section 2, the segments 9 preferably are made by adie forming operation.

While I have shown and described above the preferred construction embodying the present invention, it is to be understood that my invention is not to be limited to the specific details shown and described above, but that, in fact, different means may be employed in carrying out the broader aspects of my invention.

What I claim, therefore,.and desire to secure by Letters-Patent is:

l. A plow disk comprising a dished center disk section having an inner substantially continuous concave surface, a plurality of peripheral wear resisting sections, the inner surface of each of which is dished to form a continuation of the concave surface of said center disk section, and

means connecting said peripheral sections to said center section with the major part of the ends of said peripheral sections in edge to edge contact.

2. A plow disk comprising a dished center disk section having an innersubstantially continuous concave surface and formed of tough semi-soft steel resistant to-shocks and the like, a'detachable peripheral section formed of hard wear-resistant steel, the inner surface of said detachable peripheral section being 'dished'to form a continuation of theconcave surface of said center disk section, said tough center disk section resisting shocks and the like and the hard peripheral section taking the wear during operation, one of said sectionsbeing offset to receive the adjacent edge of the other section and dispose the concave surfaces of the sections substantially flush, and means connecting said sections together.

3. A plow disk comprising a dished center disk section having a continuous uninterrupted inner concave surface, said center disk section having an annular offset peripheral portion, a

detachable peripheral section the inner surface of which'is dished to form a continuation of the concave surface of said center disk section, said detachable peripheral section having a radially outer sharpened edge and the thickness of said equal to the thickness of said peripheral section,

and a plurality of fastening means passing through the radially inner portion of said detachable peripheral section and the adjacent parts of said offset portion of the center disk section for securing said detachable peripheral section thereto.

4. A plow disk comprising a dished center disk section formed of tough resilient semi-soft steel and having an inner continuous concave surface and a peripheral offset portion, a detachable peripheral section comprising a plurality of separate dished segments, each formed of hard wear resistant metal and having a concavity corresponding to the concavity of said center disk section, the amount of offset of the peripheral portion of the latter being substantially equal to the thickness of said segments at their radially inner portions thereof, whereby the inner surface of the several segments form a continuation of the inner concave surface of said center disk section, each of said segments having a sharp-. ened cutting edge and each radially outer corner of each segment being cut off so as to remove a portion of the sharpened cutting edge back to the part of the segment of substantial thickness, the remaining edge portions of the segments being supported on said peripheral offset portion in substantial contact, and means fixing said segments to said ofiset portion.

5. A plow disk comprising a center section and a plurality of segmental sections secured thereto, each of said segments having a sharpened cutting edge and each radially outer corner of each segment being cut off so as to remove a portion of the sharpened cutting edge back to the part of the segment of substantial thickness, thereby forming notches in the outer periphery of the disk with generally circular cutting edge sections therebetween, whereby the engagement of ground trash and the like by the notches ensure rolling of the disk in operation and the rolling of the disk in operation causing the circular cutting edges to cut through the trash.

6. A plow disk segment comprising a part having a cutting edge, the corners of said part being out 01f at opposite ends of said cutting edge.

7. A plow disk segment comprising a part beveled on one side to form a cutting edge, the corners of said part at each end of the cutting edge being formed on a diagonal which extends at a relatively large angle, greater than 90, to the adjacent portion of the cutting edge.

8. A plow disk comprising a dished center disk section having an inner concave surface, a detachable peripheral section comprising a plurality of separate dished segments, each having a concavity corresponding to the concavity of said center disk section, one of said sections having an ofiset portion overlapping the back of the other section, the amount of ofiset being substantially equal to the thickness of the adjacent part of said other section, whereby the inner surfaces of the several segments form a continuation of the inner concave surface of said center disk section, each of said segments having a sharpened cutting edge.

9. A plow disk comprising a center disk section having an inner substantially continuous surface, a plurality of peripheral wear resisting sections, the inner surface of each of which is adapted to form a continuation of the inner surface of said center disk section, and means connecting said peripheral sections to said center section with the major part of the ends of said peripheral sections in edge to edge contact.

10. A plow disk comprising a center disk section having a continuous uninterrupted inner surface, said center disk section having an annular ofiset peripheral portion, a detachable peripheral section the inner surface of which forms a continuation of the inner surface of said center disk section, said detachable peripheral section having a radially outer sharpened edge and the thickness of said peripheral section being substantially uniform except at the sharpened edge portion thereof, the amount of offset of said ofiset portion being substantially equal to the thickness of said peripheral section, and a plurality of fastening means passing through the radially inner portion of said detachable peripheral section and the adjacent parts of said offset portion of the center disk section for securing said detachable peripheral section thereto.

11. A plow disk comprising a dished center disk section formed of tough resilient semi-soft steel, a detachable peripheral section comprising a plurality of separate dished segments, each formed of hard wear resistant metal and having a concavity corresponding to the concavity of said center disk section, each of said segments having a sharpened cutting edge and each radially outer corner of each segment being cut off so as to remove a portion of the sharpened cutting edge back to the part of the segment of substantial thickness, the remaining edge portions of the segments being supported on said peripheral offset portion in substantial contact, and means fixing said segments to said offset portion.

12. A plow disk comprising a center disk section having an inner continuous surface and a peripheral offset portion joined together by a slanting section, a detachable peripheral section, the amount of offset of the peripheral portion of the latter being substantially equal to the thickness of at least the cooperating radially inner portion of the detachable peripheral section and the radially inner edge of the latter being beveled so as to fit said slanting section, whereby the inner surface of the detachable peripheral section forms a continuation of the inner surface of the center section, and means connecting the peripheral section to said ofiset portion.

CARL G. STRANDLUND.