Cutterbar Improvements In A Harvesting Machine

Abstract

An elongated stiffener is provided along a portion of the rear edge of a barback. A ball joint connects one end of a barback brace rod to the inner end of the stiffener. Both the brace rod and the stiffener extend from the ball joint generally towards a drive rod for a sickle which is mounted on and extends forwardly from the barback. The stiffener is located behind and extends between a pair of guide blocks on the barback which receive and guide a moving guide bar which is a part of the sickle drive. The barback stiffener is about the same thickness as the barback and is about one-half the width of the barback. It adds section modulus to the barback in a region of the barback which without such extra section modulus would be bent by forces imposed on it by the drive rod for the sickle.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to harvesting machines, and more particularly to a barback improvement in a floating cutter bar for such machines.

2. Description of Prior Art

Floating cutter bars have been used in conjunction with harvesting machines for a considerable period of time. It is known to brace the floating cutter bar by means of a brace rod inner-connected between (1) a barback location inwardly of where a driving force is imposed on the cutter bar by a sickle drive rod and (2) a frame portion of the harvesting machine located laterally outwardly of and above the location of force application. However, the known prior art installations have been found to experience unwanted permanent bending in the barback between the connection point of the barback brace rod to the barback and the location where the sickle drive force is applied to the barback.

SUMMARY OF THE INVENTION

According to the present invention at least severe permanent bending of the barback is prevented by an arrangement by which the barback end of the support rod is pivotedly connected to a connector member which projects upwardly from a stiffener which has been added to the barback. The stiffener extends from the vicinity of the pivot joint towards the sickle drive mechanism along the rear edge of the barback. The stiffener is substantially equal in thickness to the barback and is about one-half again as wide. It terminates between a pair of upstanding guide blocks on the barback which receive and guide an elongated guide bar which is a part of the sickle drive mechanism. The stiffener is quite simple and adds no additional structure to the cutter bar than is necessary. It provides sufficient additional section modulus in that region of the barback which receives the bending force imposed by the sickle drive mechanism to prevent a permanent bend from being "set" into the barback.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a reduced scale front elevation view of a harvesting machine of a type having a flexible floating cutter bar;

FIG. 2 is a cross-section view taken through the floating cutter bar assembly and a lower portion of a crop collection trough;

FIG. 3 is a schematic top plan view of the support system of the flexible floating cutter bar;

FIG. 4 is an elarged scale cross-section view taken along line 4--4 of FIG. 3;

FIG. 5 is a fragmentary isometric view of a forward portion of a harvesting machine, taken from above and looking towards the front and a side of the machine at the drive end for the sickle, such view being cut away in part and showing some feeder panels removed, for the purpose of better illustrating the barback strengthening and bracing mechanism of this invention;

FIG. 6 is a fragmentary top plan view of the cutter bar in the vicinity of the barback brace rod, with the feeder panels removed, such brace rod being shown in spaced relationship to the barback and the support frame member on the harvesting machine to which it is attached; and

FIG. 7 is an enlarged scale fragmentary view of the taper seat ball joints used at each end of the barback brace rod.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a harvesting machine 10 equipped with a floating cutter bar 12. A rotating pick-up reel gathers the growing crop and feeds it to the cutter bar 12 which severs such crop adjacent the ground. As the machine moves forwardly the cut crop moves upwardly over feeder panels 16 (FIG. 2) into a collection trough 18.

The cutter bar 12 is supported by a plurality of floating shoe assemblies 20. The forward ends of the floating shoe assemblies are secured to a relatively thin support member termed a "barback," designated 22 in the drawing. By way of typical example the barback 22 may measure about three-eighths of an inch in vertical heighth or thickness and about three inches in width or horizontal dimension from its leading edge to its trailing edge. As a result, the barback 22 is quite flexible in the vertical direction but resists bending in the horizontal direction. This flexible property of the barback in the vertical direction, together with the floating shoe support, enables the cutter bar to closely follow the contour of the ground. As best shown by FIG. 2, the shoes are solidly connected at forward ends to the barback 22 and are hinge connected at their rearward ends to a support strut 23. A flat shoe spring S is interconnected between a front shoe hanger FSH on the machine frame and the rear portion of the shoe 20. The strut 23 is attached to and depends from a rear mount tube RMT constituting a part of the machine frame.

As shown by FIGS. 2, 5 & 6, a plurality of sickle guard members are bolted or otherwise secured to the barback 22. In the illustrated embodiment each guard comprises a pair of points 24 which project forwardly from a base of its guard which is located below the barback 22 and is secured to the barback 22 by nut and bolt assemblies 26. Forwardly of the barback 22 each point 24 projects upwardly and is formed to include a rearwardly opening guide slot for receiving sickle knives 28. During sickle movement the knives 28 pass back and forth over the lower surfaces (viz. the "ledger" surfaces) of these slots, producing a scissors-like sheering action.

The knives are connected at their rear ends to a sickle bar 30 which is also vertically thin so that it is vertically flexible and will readily bend with the barback 22. Hold down clips 32 for the sickle bar 30 are secured to the barback 22.

Referring now to FIG. 6, the sickle bar 30 is shown to include a rearwardly extending drive plate 34 which extends back over the barback 22. An elongated guide bar 36 is secured to plate 34. Bar 36 extends in parallelism with the barback 22 and includes opposite end portions which are slidably received within guide ways in a pair of spaced apart guide blocks 38 which are secured to the barback 22. A pitman 40 is interconnected between a rear portion of the drive plate 34 and a drive crank 42. In the illustrated embodiment the rod 40 is connected to plate 34 by a ball joint connector 46 and to the crank 42 by a ball joint connecter 48. A rod 44 is ball joint connected at 50 to crank 42 and at its opposite end is simularly connected to a pitman wheel (not shown). The pitman wheel moves the rod 44 endwise back-and-forth (as indicated by arrow 52) and such rod 44 swings the crank 42 back-and-forth in the direction indicated by the arrow 54. Crank 42 in turn moves rod 40 endwise back-and-forth as indicated by directional arrow 56. Rod 40 in turn moves the sickle bar 30 endwise back-and-forth and the knives 28 sideways relative to the ledger surfaces on the points 24, to produce a sheering action for cutting the crop. It is to be understood that the drive crank 42, rod 44, the pitman wheel, etc. are all parts of the combine and may have different counterparts in other makes of combines.

Referring now to FIG. 6, movement of rod 40 to the left (as pictured) imposes a downward force on the barback 22 through the guide blocks 38. Movement of drive rod 40 in the opposite direction (i.e., to the right as pictured) imposes an upward force on the barback 20.

The above described drive mechanism for the sickle is generally known. It is also known to brace the barback in the vicinity of where the drive force is applied to the sickle bar by means of a brace rod which is interconnected between a portion of the harvesting machine frame on the drive rod side of the connection 46 and a location on the barback 22 on the opposite side of the connection 46. However, a problem with these prior arrangements is that a permanent bend often developed in the barback between the connection point of the brace rod and the location of force applied on the barback by the sickle drive mechanism.

According to the present invention an elongated stiffener 58 is provided along the rear edge of the barback 22 for the purpose of strengthening the barback vertically in the region where the sickle drive force tends to set a bend into the barback 22 during downward movement of drive rod 40. The stiffener is in the nature of an elongated bar 58 which is substantially the same thickness as the barback material and is about 50 percent the width of the barback 22. With a barback measuring three-eighths of an inch thick and 3 inches wide it was found that the best results were obtained by a stiffener measuring about 11/2 inches wide.

According to the invention the stiffener 58 extends from about the point of connection of a support rod 60 to the barback 22 lengthwise of such barback 22 towards the drive rod 40 and terminates rearwardly of the outer guide block 38 (FIG. 6). A socket member 62 for receiving the tapered base of a tapered seat ball joint 66 is welded to the upper surface of the stiffener 58 and has opposite face portions which are perpendicular to the upper and lower surfaces of the barback 22.

As best shown by FIG. 7, a spherical head 70 is connected to the tapered shank 64 and is positioned rearwardly of the member 62. A ring 72 having a complementary inner spherical surface surrounds the ball member 70. A threaded shank 74 extends from ring 72 into threaded engagement with an end member 76 welded onto the end of brace rod 60. A lock nut 78 is provided on the shank 74 endwise outwardly of rod 60 from end member 76. The ball member 64, 70 is secured into place by means of a securement nut 82 which threads onto a threaded shank portion 80, and by a lock nut 84. The joint assembly 68 at the opposite end of rod 60 is of like construction so it will not be separately described.

From the foregoing, various modifications of the barback stiffening and bracing arrangement will be apparent to those skilled in the art to which the invention is addressed, within the scope of the following claims.

After considerable experimentation with other arrangements it was found that the illustrated and above described barback stiffener arrangement protected the barback against unwanted "set" without interferring with the desired floating action of the cutter bar.

Claims

What is claimed is:

1. In a floating, flexible, harvesting machine cutter bar of a type comprising a vertically thin and flexible barback supported for travel over uneven ground by a plurality of laterally spaced apart support shoes, and a sickle carried by the barback which is driven by means including a reciprocating sickle drive rod which moves the sickle endwise back-and-forth along a forward edge portion of the barback and in so doing imposes a downward bending force on the barback while pushing the sickle and an upward bending force on the barback while pulling the sickle, an improved barback construction and barback bracing arrangement comprising:

an elongated stiffener that is substantially the same thickness as the barback, secured along a rear edge portion of the barback in the region where a bending force is applied on the barback by the sickle drive rod, said stiffener adding width and section modulus to the barback throughout its extent, a brace rod connector member extending upwardly from the stiffener, said stiffener extending from said brace rod connector member along the barback toward the sickle drive rod, and a brace rod having a universal joint connector at one of its ends for connection to said rod connector member and a universal joint connector at its opposite end for connection to a frame portion of the harvestor located above and to the rear of the barback and spaced from such brace rod connector member towards the sickle drive rod.

2. The improvement of claim 1, wherein said rod connector member included a conical socket and the universal joint connector to be connected thereto includes a conical shank snuggly receivable in said socket.

3. The improvement of claim 2, wherein said universal joint connector further includes a ball member connected to said shank, said ball member in use being disposed rearwardly of said rod connector member, and a socket member on the sickle rod engaging said ball member.