Abstract:
The chipper drum of the present disclosure is configured to maximize its cutting width while decreasing its overall size. In particular, the chipper drum of the present disclosure includes air deflectors recessed on the ends of the drum that are configured to generate the air flow necessary to blow chips out of the chipper.

Description:
This application is a National Stage Application of PCT/US2008/062214, filed May 1, 2008, in the name of Vermeer Manufacturing Company, a U.S. national corporation, applicant for the designation of all countries except the US, and Edwin N. Galloway, James L. O&#39;Halloran, Jeffrey D. Bradley, John T. Bouwers and Larry Schut, citizens of the U.S., applicants for the designation of the US only, and claims priority to U.S. Provisional Patent Application Ser. No. 60/928, 928, filed May 10, 2007, and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications. 
     TECHNICAL FIELD 
     The present invention relates generally to a chipper and, more particularly, to a chipper having a chipper drum with an integral blower. 
     BACKGROUND 
     Chippers are used to reduce branches, trees, brush, and other bulk wood products into small chips. A chipper typically includes an infeed chute, a feed system for controlling the feed rate of wood products into the chipper, a chipping mechanism, a drive system for powering the feed system and the chipping mechanism, and a discharge chute. For a description of an infeed chute see WOOD CHIPPER INFEED CHUTE, incorporated in its entirety herein by reference. 
     The chipping mechanism is commonly a large cutter drum that includes blades thereon. The drum is commonly driven by an engine via a belt. For a description of a belt drive system see BELT TENSIONING APPARATUS, incorporated in its entirety herein by reference. The drum is used to grind, flail, cut, or otherwise reduce the material fed into the chipper into small chips. Besides acting as the chipping mechanism, the drum is also commonly used to generate the air flow necessary to propel the cut chips out of the chipper. 
     In some prior art systems, paddles are attached to the ends of the drums to generate pressure needed to blow the chips out the discharge chute.  FIG. 1  depicts a known chipper drum  10  within a drum housing  12 . The chipper drum  10  is cylindrical in shape and includes a number of blades  14  and chip pockets  16  spaced apart on the cylindrical surface of the drum  10 , and paddles  18  attached to the end surface of the drum  10 . As the chipper drum  10  rotates about axis A in a counterclockwise direction B, it draws air into the inlet end  20  of the drum housing  12 . The air flow between the chipper drum  10  and the housing  12  is accelerated by the paddles  18  through the outlet  22  of the chipper housing  12 . This air flow blows the chips out of the chipper  10 . In many prior art systems, the chips are blow out the rear of the chipper, which is undesirable as such chips are blow towards the operators who load the chippers from the rear. 
       FIG. 2  shows the chipper drum  10  rolled out flat into a rectangular shape. The paddles  18  in the known system extend beyond the edges of the cylindrical surface of the drum  10 . The cylindrical surface or skin of the drum defines the cutting width W 1  of the drum  10 . The cutter drum housing width W 3  needs to be large enough to allow space for the width W 2  of the drum, which accounts for the portion of the paddles  18  that extend beyond the width W 1  of the skin of the cutter drum  10 . 
     Referring to  FIG. 3 , a schematic top view of a chipper  24  is shown. The chipper  24  includes a feed table  26  at the rear end of the chipper  24 , a discharge chute  28  at the front end of the chipper  24 , and a drum housing  12  therebetween. Feed rollers (not shown) are aligned with and positioned between the feed table  26  and the chipper housing  12 . For a description of feed rollers see WOOD CHIPPER FEED ROLLER, incorporated in its entirety herein by reference. The engine  30  is positioned at the left side of the chipper  24 , and the drive system  32  is positioned at a right side of the chipper  24 . Increasing the width W 3  of the chipper drum housing  12  would result in increasing the overall width W O  of the chipper  24 . Conversely, decreasing the width W 3  of the chipper drum housing  12  would enable the overall width W O  of the chipper to be decreased. Since it is desirable to minimize the overall width W O  of the chipper  24  and maximize the effective cutting width W 1  of the drum  10 , it is desirable to minimize the difference between the width of the cutter drum housing W 3  and the width W 1  of the cutter drum surface. 
     SUMMARY 
     The present disclosure relates to a chipper drum that includes a blower system housed within the drum. In one embodiment, air deflectors are located within recesses at the ends of the drum. The air deflectors cooperate with the drum housing to pressurize the chipper body, thereby causing chips within the body to propel out of the body through the discharge chute. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a prior art chipper drum and chipper drum housing; 
         FIG. 2  is a view of the chipper drum rolled out in a flat plan view for explanatory purposes; 
         FIG. 3  is a diagrammatic view of a prior art chipper layout; 
         FIG. 4  is a side view of a chipper with the chipper housing and chipper drum shown in hidden lines; 
         FIG. 5  is a perspective view of a first embodiment of a chipper drum and chipper drum housing according to the principles of the present disclosure; 
         FIG. 6  is a perspective view of the chipper drum of  FIG. 5 ; 
         FIG. 7  is a perspective view of the chipper drum housing of  FIG. 5 ; 
         FIG. 8  is a view of a chipper drum rolled out in a flat plan view for explanatory purposes; 
         FIG. 9  is a diagrammatic view of a chipper layout incorporating the principles of the present disclosure; 
         FIG. 10  is a perspective view of a second embodiment of a chipper drum and chipper drum housing according to the principles of the present disclosure; 
         FIG. 11  is a perspective view of the chipper drum housing of  FIG. 10 ; 
         FIG. 12  is a perspective assembly view of the chipper drum housing of  FIG. 10 ; 
         FIG. 13  is a perspective view of the chipper drum of  FIG. 10 ; 
         FIG. 14  is a cross-sectional view of the chipper drum and chipper drum housing generally along line  14 - 14  of  FIG. 10 ; 
         FIG. 15  is a cross-sectional view of the chipper drum and chipper drum housing generally along line  15 - 15  of  FIG. 10 ; 
         FIG. 16  is a cross-sectional view of a third embodiment of a chipper drum and chipper drum housing; 
         FIG. 17  is a cross-sectional view of a fourth embodiment of a chipper drum and chipper drum housing; 
         FIG. 18  is a diagrammatic view of chips moving through a chipper drum housing according to the principles of the present disclosure; and 
         FIG. 19  is a view of  FIG. 18  with dimensions. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 4 , a chipper  40  is shown. In the depicted embodiment the chipper  40  is mounted to a frame  42  that is supported on wheels  44 , which enable the chipper  40  to be conveniently moved. The depicted chipper  40  includes an infeed chute  46 , which is also commonly referred to as a feed table. The infeed chute  46  can be any structure located at the rear of the chipper  40  that facilitates the loading of materials to be chipped into the chipper  40 . (The material to be chipped can be any material that the user desires to reduce to chips. The material is most commonly brush and tree parts, therefore, for convenience the material to be chipped will be referred to herein as wood, trees, or brush.) As discussed in the background, a description of an infeed chute can be found in WOOD CHIPPER INFEED CHUTE. The chipper  40  in the depicted embodiment includes an infeed system that grabs and pulls brush from the infeed chute  46  into a central body portion  48  of the chipper  40 , which houses cutter-drum  50  that cuts the brush into small chips. A description of an infeed system is provided in SYSTEM FOR CONTROLLING THE POSITION OF A FEED ROLLER, which is incorporated in its entirety herein by reference. Once the cutter drum  50  reduces the materials to be chipped into chips, the chips are expelled from the chipper  40  through the discharge chute  52 . 
     Referring to  FIG. 5 , a first embodiment of a cutter drum  60  and cutter drum housing  62  of a chipper  40  according to the present disclosure is shown. The cutter drum  60  includes air deflectors (e.g., paddles)  64 ,  66  located within end portions  68  of the cutter drum  60 . In the depicted embodiment the air deflectors extend radially along recessed end surfaces of the cutter drum  60 . Though the air deflectors are shown as rectangular shaped members in  FIG. 5  and scooped shaped in  FIG. 13 , it should be appreciated that many other air deflector configurations are also possible. Since the opposed end portions  68  of cutter drum  60  in the depicted embodiment are similar, only the right side of the drum  60  shown in  FIG. 5  is described in detail herein. As the drum rotates about its axis AA in the counterclockwise direction BB, air flows from the outside of the chipper drum housing  62  through aperture  70  and is accelerated by the air deflectors  64 ,  66  over an edge  74  of a drum skin  72  and out the discharge chute  52 . 
     Referring to  FIGS. 6-8 , the cutter drum  60  and the cutter drum housing  62  are shown in greater detail. The cutter drum  60  includes auxiliary structural supports  76  on the end portion  68  of the cutter drum  60  adjacent the chip pockets  78 . In the depicted embodiment, the chip pockets  78  are located directly in front of the blades  80 . Also, auxiliary deflectors  82 ,  84 , and  86  are located adjacent the deflectors  64 ,  66  to facilitate air flow and prevent debris buildup on the cutter drum  60 . It should be appreciated that many other configurations are also possible. 
     Referring to  FIGS. 7-8 , the cutter drum housing  62  includes a drum chamber  88 , an axis support  90 , an inlet  92 , and an outlet  94 . The cutter drum housing  62  includes a width W 5  that is slightly larger than the width W 4  of the cutter drum  60 . In the depicted embodiment the width W 4  of the cutter drum  60  is also the effective cutting width of the cutter drum  60 . The width W 5  of the housing is also the maximum width of the cutter drum  60 . In the depicted embodiment the width W 5  is less than 6 inches greater than W 4 . Preferably, W 5  is less than 1.5 inches greater than W 4 . In the depicted embodiment, W 5  is approximately 28¾ inches and W 4  is approximately 28 inches. Referring specifically to  FIG. 8 , the cutter drum housing  62  is shown rolled out flat with air flow channels shown as notches  96 . The notches  96  allow air to flow over the edges  74  of the cutter drum  60 . In the depicted embodiment the width W 5  of the cutter drum  60  varies. In one embodiment the width varies by more than 1 inch and the minimum width W M  of the drum is located at the notches  96 . Though in the depicted embodiment the notches  96  are offset from the chip pockets  78 , it should be appreciated that in alternative embodiments of the drum  60  the notches  96  can be in other locations as well. 
     Referring to  FIG. 9 , a chipper layout according to the principles of the present disclosure is shown. Like  FIG. 3 , the chipper  24 ′ includes a feed table  26 ′ at the rear end of the chipper  24 ′, a discharge chute  28 ′ at the front end of the chipper  24 ′, and a drum housing  12 ′ therebetween. Feed rollers (not shown) are aligned with and positioned between the feed table  26 ′ and the chipper housing  12 ′. The engine  30 ′ is positioned at the left side of the chipper  24 ′, and the drive system  32 ′ is positioned at right side of the chipper  24 ′. Since the air deflectors  64 ,  66  of the chipper  24 ′ of the present disclosure are recessed relative to the edge  74  of a drum skin  72  of the cutter drum  60 , the cutter drum  60  has a relatively larger cutting width than the same width cutter drums of the prior art. In the depicted embodiment the air defectors  64 ,  66  overlap the blades  80  of the cutter drum  60  along the width of the cutter drum  60 . In the depicted embodiment, the width W 5  of the cutter drum housing  62  is closer to the width W 4  than is the width W 3  to width W 1  of  FIG. 3  (prior art). The depicted embodiment increases the effective cutting width W 4  of the cutter drum  60  without increasing the width W 5  of the cutter drum housing  62 . In the depicted embodiment the width W 5  is ¾ inches greater than the width W 4 . 
     Referring to  FIGS. 10-15 , a second alternative embodiment of a chipper drum  100  and chipper drum housing  102  is shown. Like the first embodiment, the chipper drum  100  and chipper drum housing  102  of the second embodiment are configured such that the width W 6  of the cutting drum  100  is maximized while the width W 7  of the cutter drum housing  102  is minimized. The cutter drum housing  102  includes a drum chamber  88 ′, an axis support  90 ′, an inlet  92 ′, and an outlet  94 ′. The cutter drum housing  102  includes a width W 7  that is slightly larger than the width W 6  of the cutter drum  100 . The cutter drum housing  102  also includes a housing deflector  104  for preventing air and chips from being projected out of the inlet  92 ′ of the cutter drum housing  102 . Referring particularly to  FIG. 12 , the housing deflector  104  is shown in an assembly view as being mounted to the cutter drum housing  102  through a slot  106  via nuts  108  and bolts  110 . 
     Referring to  FIG. 13 , the cutter drum  100  of the second embodiment does not include notches to facilitate air flow. Instead, the drum is constructed to direct air from the ends  112  of the cutter drum through a window  114  in the chip pocket  78 ′. In the depicted embodiment the ends are generally perpendicular to the rotational axis AAA of the drum and recessed relative to the cutting surface of the drum  100 . Like the cutter drum  60  of the first embodiment, the cutter drum  100  of the second embodiment includes blades  80 ′ adjacent the chip pockets  78 ′. As the drum rotates about the axis AAA in the counterclockwise direction BBB, air from outside of the chipper drum housing  102  is accelerated by the paddles  116  and auxiliary deflectors  118  through the window  114 . In the depicted embodiment the two paddles  116  are scoop shaped with an L-shaped side profile. In the depicted embodiment the L-shaped paddles  116  are directional, that is, the paddles  116  perform differently when the drum is rotated in the clockwise direction than when the drum is rotated in the counterclockwise direction. This air flow projects the chips out of the chipper. The housing deflector  104  on the housing  102  prevents air/chips from flowing through the window  114  when the pocket  78 ′ faces the inlet  92 ′ of the chipper drum housing  102 , as it is desirable to blow the chips through the outlet  94 ′ rather than the inlet  92 ′.  FIG. 14  is a cross-sectional view of the cutter drum  100  and cutter drum housing  102  of  FIG. 10  generally along line  14 - 14 .  FIG. 15  is a cross-sectional view of the cutter drum  100  and cutter drum housing  102  of  FIG. 10  generally along line  15 - 15 .  FIGS. 14 and 15  illustrate how the housing deflector  104  blocks the window  114  when the chip pocket  78 ′ faces the inlet  92 ′ of the cutter drum housing  102  to facilitate chips being ejected out of the discharge chute  52 ′ rather than the inlet  92 ′. 
       FIGS. 16 and 17  show the cutter drum  100  being housed within cutter drum housings  120 ,  122 , which are similar to the cutter drum housing  102  of the second embodiment. The difference between the cutter drum housings  120 ,  122  relates to the size of the housing deflectors  124 ,  126 . 
     Referring to  FIGS. 18 and 19 , the cutter drum housing  130  includes an upper  132  and a lower  134  housing chip deflector. In the depicted embodiment, the chip defectors  132  and  134  extend substantially across the width of the drum  136 . The upper and lower housing chip deflectors  132  and  134  are positioned to direct chips from the cutter drum housing  130  to the discharge chute  52 ″ and to further prevent chips from discharging through the inlet  92 ″. The upper housing chip deflector  132  primarily functions to deflect chip towards the discharge chute  52 ″, whereas the lower housing chip deflector  134  primarily functions to prevent chips from being ejected out of the inlet  92 ″ of the housing  130 . In the depicted embodiments the upper and lower housing chip deflectors  132  and  134  are adjustable. In the depicted embodiment the radius R of the cutter drum  136  measured from the axis of rotation of the cutter drum  136  to the edge of the blade  80 ″ is between 6-25 inches. More preferably, the radius R is between 10-18 inches. In the depicted embodiment, the gap G 1  between the near edge of the upper housing chip deflector  132  and the far edge of the blade  80 ″ in the radial direction is between 0.0315-0.25 inches. More preferably, the gap G 1  is between 0.0625-0.1875 inches. In the depicted embodiment, the gap G 2  between the near edge of the lower housing chip deflector  134  and the far edge of the blade  80 ″ in the radial direction is between 0.0315-0.25 inches. More preferably, the gap G 2  is between 0.0625-0.1875 inches. Since these deflectors are adjustable, the gaps G 1  and G 2  can be more easily made relatively smaller than if the chip deflectors were welded to the drum. 
     The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.