This invention relates to blades for bale processing machines, and more particularly to a forged blade having a large cutting area to improve the efficiency of a bale processing machine.
Bale processing machines are used primarily in the livestock agricultural industry to chop or shred bales of straw or hay for animal feed and bedding material. Typically such a machine includes a rotating drum that has a number of blades mounted on pivot pins circumferentially and longitudinally distributed over the surface of the drum. The blades hang from the pins when the drum is stationary and extend radially outward from the drum when the drum is rotated at a sufficient operating speed. Cutting edges extending across the blades at an end opposite the pins cut baled material that is fed through the machine for processing.
The type of blade used in these machines features an eye portion through which the pivot pin is passed and a blade portion extending from the eye portion to a cutting edge at the end. Conventionally these blades have been of uniform width, meaning that the width of the cutting edge at the end of the blade portion has been the same width as the eye portion. In this uniform design, increasing the size of the cutting edge requires an increase of the blade's width over its entire length, thereby significantly increasing the mass of the blade. The increase in mass and the increase in size of the cutting edge counteract each other, as the added mass decreases the efficiency of driving the rotating drum while the change in the cutting edge increases the effective cutting area of the machine.
As a result, there is a desire for a blade assembly for a bale processing machine offering an increase in effective cutting area while minimizing the corresponding increase in blade mass.
According to a first aspect of the invention there is provided a bale processing machine comprising:
a frame;
a drum supported on the frame for rotational motion about a longitudinal axis of said drum;
a plurality of pivot pins supported on an outer surface of the drum, each pivot pin extending along said drum; and
a plurality of blade members each comprising:
an eye portion having a cylindrical opening therein through which a respective one of the pivot pins passes; and
a curved blade portion extending longitudinally from the eye portion in a direction radially outward from the cylindrical opening of said eye portion, said curve blade portion having a cutting edge at an end opposite said eye portion;
each blade member being pivotally supported on the respective pivot pin for motion between a hanging position in which said blade member hangs from said pivot pin and a cutting position in which said blade member extends generally radially outward relative to the drum from said pin;
the curved blade portion of each blade member being wider at the cutting edge than at the eye portion;
the drum being driven for rotation such that the blade members pivot to the cutting position during said rotation.
The blades of the drum assembly are wider at their cutting edges than at their eye portions where they are pivotally mounted on the pins. This results in a larger cutting area per blade with a smaller increase in mass than that associated with widening the blade over its entire width.
Preferably the curved blade portion of each blade member gradually increases in width toward the cutting edge. This prevents the formation of corners associated with a sudden jump in width. Corners act as stress risers that weaken the blade. The smooth increase in width maintains a high level of strength in the blade.
The cutting edge of each blade member may be parallel to a longitudinal axis of the cylindrical opening of the eye portion. Alternatively, the cutting edge of each blade member may be disposed at a relative angle to a longitudinal axis of the cylindrical opening of the eye portion. In this case, preferably the curved blade portion of each blade member comprises a twisted portion extending from the eye portion toward the cutting edge, said twisted portion being twisted about one side thereof such that the blade portion is parallel to and flush with the eye portion at said eye portion and said blade portion is at the relative angle to said flat end of the eye portion between the twisted portion and the cutting edge.
Preferably the pivot pins are arranged in circumferentially spaced rows extending along the drum.
Preferably adjacent pivot pins in each row are equally spaced apart.
The rows may each have an equal number of pivot pins. In this case, the rows of pivot pins may be longitudinally aligned such that each pivot pin in one of the rows has a respective pivot pin in each of the other rows at an equal longitudinal position on the drum.
Alternatively, the rows of pivot pins may be longitudinally offset such that the pins of adjacent rows have different longitudinal positions on the drum. In the case where the cutting edge of each blade member is disposed at a relative angle to a longitudinal axis of the cylindrical opening of the eye portion and the pivot pins are arranged in circumferentially spaced rows extending along the drum, the cutting edges of adjacent blade members in each row may be angled toward opposite ends of the drum. In other words, the relative angles of the cutting edges to the longitudinal axes of the cylindrical openings of the eye portions of the adjacent blade members in each row are taken about opposite sides of said axes in opposite ones of clockwise and counterclockwise directions.
Preferably the blade members comprise forged alloy steel.
According to a second aspect of the invention there is provided a blade member for a bale processing machine, said blade member comprising:
an eye portion having a cylindrical opening therein; and
a curved blade portion extending longitudinally from the eye portion in a direction radially outward from the cylindrical opening of said eye portion, said curve blade portion having a cutting edge at an end opposite said eye portion;
the curved blade portion of each blade member being wider at the cutting edge than at the eye portion.
In the accompanying drawings, which illustrate exemplary embodiments of the present invention:
As shown in the overhead and side views of
As can be seen in
The twisted portion 52 extends from the flat end 30 of the eye portion 22 to an angled end 53 between the flat end 30 and the opposite end 26 of the blade portion 25 with the cutting edge 28. The twisted portion 52 has been twisted about one of its sides 54 such that the opposite side angles downward from the flat end 30 of the eye portion 22. The twisted portion 52 is flush with and parallel to the eye portion at the flat end 30 and deformed to a maximum angle relative to the flat end 30 at the angled end 53. The rest of the blade portion 25 extends from this angled end 53 to the cutting edge 28. As a result of the twist, the cutting edge 28 at the end 26 opposite the eye portion 22 is oriented at the same angle to the flat end 30 as the angled end 53. As seen in FIGS. 8 to 9, the cutting edge 28 of these blades 50 are not parallel to the longitudinal axis of the drum 42 of a bale processing machine, unlike those of the first embodiment. When the drum 42 extends parallel to the strands of material in the bale being processed, these blades 50 will cut the material more effectively than a blade with a cutting edge parallel to the drum as the cutting edge will extend across the strands rather than along them. Obviously, more effective cutting will break down the bale faster.
A further alternate drum assembly 80 is shown in
The blade members 20 and 50 described above are each single pieces forged from high strength alloy steel. The cylindrical opening 24 is formed in one end for attachment to a respective pivot pin 44 on the rotating drum 42 of a bale processing machine. The width is maintained in the eye portion 22 to achieve a constant land or beating area to the interfacing components. The opening 24 of the eye portion 22 may have a bushing inserted to withstand the rotating motion of the blade about the pin. The blade portion 25 extending from the eye portion is forged so that it increases in width towards the cutting edge 28. The resulting increased cutting area moves the mass towards the outer periphery of the working area giving maximum energy to the blade tip. In the second embodiment (
It should be noted that further alternate embodiments of blades having variable width can be developed through modification of those described above. While forging the blades to gradually increase in width toward the cutting edge provides improved grain structure and resulting strength of the blade, it should be appreciated that blades with widened cutting edges can be manufactured in other ways. The gradual increase also eliminates the presence of stress risers associated with corners created by a sudden increase in width, thereby maintaining a high strength in the blade. The twisted portion of the blade with the angled cutting edge may extend the full length of the blade portion and the eye portion does not have to extend as far from the cylindrical opening as shown in the figures. The pins can be arranged on the drum in any number of ways not limited to those described above and illustrated in the figures. The blades may also be made of materials other than high strength alloy steel. The blades may be used on different styles of bale processing machines having implements mounted on a rotating member to break down baled material.
Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without department from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.
This application claims benefit of U.S. provisional application 60/716,528 filed Sep. 14, 2005.
Number | Date | Country | |
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60716528 | Sep 2005 | US |