Rotary mill having releasable wedge-lock tool insert holding system

• US 6,523,768 B2
• Filed: 03/20/2001
• Issued: 02/25/2003
• Est. Priority Date: 03/29/2000
• Status: Expired due to Fees

• Current Assignee: Morbark, Inc.
• Original Assignee: Morbark, Inc.
• Inventors: Recker, Jeffrey M., Cotter, Gary J.
• Primary Examiner(s): Rosenbaum, Mark
• Application Number:
  US09/812,455
• Publication Number:
  US 20010045478A1
• Time in Patent Office: 707 Days
• Field of Search: 294/28, 144/230, 241/294, 241/189.1, 241/242
• US Class Current: 241/294
• CPC Class Codes: B02C 18/145 with knives spaced axially and circumferentially on the periphery of a cylindrical rotor unit
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A rotor assembly for comminuting scrap wood and other like material has a rotor drum including a drive shaft and at least one radially projecting tool supporting member with a tool assembly receiving pocket. A releasable tool is locked in the pocket and comprises a shank, with an outer cutting head thereon, received in the pocket to bear upon the front wall of the pocket. The shank has an inclined front wall matching the inclined front wall of the pocket. A wedge mating member has a more inclined rear surface bearing upon the inclined rear wall of the pocket and a front wall bearing upon the tool shank. The wedge has a threaded opening for a threaded abutment member which is manipulatible to draw the wedge member outwardly to releasably clamp the tool shank.

Claims

1. A rotor assembly for comminuting scrap wood and other like material comprising:

a. a rotor drum including a drive shaft for rapidly rotating said rotor drum in a forward direction of travel and further including at least one radially projecting tool supporting member having a peripheral surface with at least one tool assembly receiving pocket provided therein having an inclined front wall and an oppositely inclined rear wall extending outwardly from a pocket floor;

b. a releasable comminuting tool comprising an elongate shank, with a cutting head thereon having a cutter tooth with a leading cutter edge facing in said direction of travel, received in said pocket and bearing upon said front wall of said pocket, said shank having an inclined front wall surface and being received to dispose said cutting head outwardly of said pocket; and

c. a wedge including a rear inclined surface bearing upon said rear wall of said pocket and a front wall bearing upon said tool shank, said wedge having a threaded opening with an elongate threaded abutment member therein having an inner end extending to bear upon said pocket floor manipulatible to draw said wedge member outwardly when manipulated with its inner end in bearing engagement with said pocket floor, said angle of inclination of said inclined rear wall of said wedge being greater than the angle of inclination of said inclined tool shank surface to provide a differential inclination.

2. The rotor assembly of claim 1 wherein said pocket is intersected by a radial axis also intersecting the axis of said drive shaft and said tool shank is disposed well forwardly of said radial axis, and said front surface of said wedge and rear surface of said tool shank extend parallel to said radial axis.

3. The rotor assembly of claim 2 wherein said differential inclination is on the order of three to one.

4. The rotor assembly of claim 3 wherein said front wall of the tool shank and front wall of the pocket are in mating engagement and extend outwardly at an angle of about 3 degrees relative to a plane parallel to said radial axis, and said inclined wedge rear wall and said rear wall of said pocket are in mating engagement and extend outwardly at an angle of about 10 degrees relative to a plane parallel to said radial axis.

5. The rotor assembly of claim 4 wherein said tool head comprises a wedge shaped body provided on said tool shank and has outer and front side relief surfaces extending from said cutter edge.

6. The rotor assembly of claim 5 wherein said abutment member is a bolt with its head received in a recess provided in an outer relieved surface of said wedge, said wedge extending outwardly in locked position to substantially a relieved surface of said tool to brace said tool.

7. The rotor assembly of claim 1 wherein said drum is formed by a series of substantially axially adjacent tool supporting members.

8. The rotor assembly of claim 1 wherein said drum is formed of a drum shaped tool supporting member.

9. The rotor assembly of claim 1 wherein said floor incorporates a raised step beneath said tool shank which is engaged by the inner end of said tool shank.

10. The rotor assembly of claim 1 wherein said pocket is provided in a segment having curvilinear outer walls conforming to the interior of said tool supporting member and said segment fixes to said drum.

11. The rotor assembly of claim 1 wherein a deflector member is removably secured to said segment forwardly of said pocket.

12. A rotor for comminuting scrap wood and other like material comprising:

a. a rotor drum including a drive shaft for rapidly rotating said rotor drum in a forward direction of travel and further including at least one radially projecting tool supporting member having a peripheral surface with at least one tool assembly receiving pocket provided therein and having a front wall and a rear wall extending convergently outwardly from a pocket floor having a front step;

b. a releasable comminuting tool comprising an elongate shank, with a cutting head thereon having a cutter tooth with a leading cutter edge facing in said direction of travel, received in said pocket on said step to dispose said head outwardly of said pocket in bearing engagement with said front wall of said pocket; and

c. a wedge including a rear inclined surface bearing upon said rear wall of said pocket and a front wall bearing upon said took shank, said wedge having a threaded opening extending substantially perpendicularly to said pocket floor with an elongate threaded abutment member therein having an inner end extending to bear upon said pocket floor rearwardly of said step manipulatible to draw said wedge outwardly from an inward position to a shank locking position when manipulated with its inner end in bearing engagement with said pocket floor, said wedge from front to rear being of such width as to leave a gap between said wedge front wall and step and said wedge front wall and tool shank when the wedge is in said inward position.

13. The rotor assembly of claim 12 wherein said pocket is bisected by a radial axis and said tool shank is disposed well forwardly of said radial axis, and said front surface of said wedge and rear surface of said tool shank extend parallel to said radial axis.

14. The rotor assembly of claim 13 wherein said front wall of said pocket and front wall of said tool shank are so less inclined with respect to said rear wall of said pocket as to create a differential inclination on the order of three to one.

15. The rotor assembly of claim 14 wherein said front wall of the tool shank and front wall of the pocket are in mating engagement and extend outwardly at an angle of about 3 degrees relative to a plane parallel to said radial axis, and said inclined wedge rear wall and said rear wall of said pocket are in mating engagement and extend outwardly at an angle of about 10 degrees relative to a plane parallel to said radial axis.

16. The rotor assembly of claim 15 wherein said abutment member is a bolt with its head received in a recess provided in an outer relieved surface of said wedge, said wedge extending outwardly in locked position to substantially a relieved surface of said tool to brace said tool.

17. The rotor assembly of claim 12 wherein said drum is formed by a series of axially adjacent tool supporting members.

18. The rotor assembly of claim 12 wherein said drum is formed of a drum shaped tool supporting member.

19. The rotor assembly of claim 12 wherein said pocket is provided in a segment having curvilinear outer walls fixed to the interior of said tool supporting member and a deflector member is removably secured to said segment forwardly of said pocket.

20. A method of constructing a rotor for comminuting scrap wood and other like material comprising:

a. providing a rotor drum including a drive shaft for rapidly rotating said rotor drum in a forward direction of travel and further including at least one radially projecting tool supporting member having a peripheral surface with at least one tool assembly receiving pocket provided therein which has a front wall and a rear wall extending outwardly from a pocket floor;

b. installing a tool having an elongate shank, with a cutting head thereon having a cutter tooth with a leading cutter edge facing in said direction of travel, in said pocket and bearing upon said front wall of said pocket;

c. installing a wedge, including a rear inclined surface bearing upon said rear wall of said pocket and a front wall bearing upon said tool shank, in said pocket, said wedge having a threaded opening with an elongate threaded abutment member therein having an inner end extending to bear upon said pocket floor manipulatible to draw said wedge member outwardly when manipulated with its inner end in bearing engagement with said pocket floor; and

d. providing said front wall of said tool shank as a tool shank surface inclined substantially less than the angle of inclination of said wedge inclined rear surface.