Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27B—SAWS FOR WOOD OR SIMILAR MATERIAL; COMPONENTS OR ACCESSORIES THEREFOR
  • B27B5/00—Sawing machines working with circular or cylindrical saw blades; Components or equipment therefor
  • B27B5/29—Details; Component parts; Accessories
  • B27B5/30—Details; Component parts; Accessories for mounting or securing saw blades or saw spindles
  • B27B5/32—Devices for securing circular saw blades to the saw spindle
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
  • B23D61/00—Tools for sawing machines or sawing devices; Clamping devices for these tools
  • B23D61/02—Circular saw blades
  • B23D61/025—Details of saw blade body

Definitions

• This invention relates to a saw blade and a drive system therefore and, more particularly, to a sawblade and its associated drive spline having a specific driving configuration.
• Circular type sawblades for use in cutting cants or lumber are of course known as are their associated drive splines.
• the drive spline has a series of rounded or convex male drive pieces spaced intermittently and circumferentially around the drive spline. These male drive pieces mate with corresponding concave female recesses in the saw blade.
• the sawblade is mounted onto the drive spline endwise. It slides over the spline until the desired operating position on the drive spline is reached. Under operating conditions, the sawblade is maintained in its desired position with sawguides which prevent undesirable movement in the sawblade. This keeps the kerf or cutting width created by the blade narrow which is desirable in order not to avoid wood wastage during the sawing operation.
• a sawblade of circular configuration having an axis of rotation, an outer cutting edge and a plurality of inner driven surfaces defined by a first angular distance between a first radial and a second radial.
• the first and second radials contact each end of a respective one of the driven surfaces located most closely to the axis of rotation.
• a second angular distance is defined between a third radial and a fourth radial, with the third and fourth radials contacting each end of the respective one of the driven surfaces located most remotely from the axis of rotation.
• the angular distance between the first and second radials is greater than the angular distance between the third and fourth radials.
• a drive spline of circular configuration having an axis of rotation, a plurality of outer drive recesses defined by a first angular distance between first and second radials, and a second angular distance between third and fourth radials.
• the first and second radials contact each end of a respective one of the drive recesses located most closely to the axis of rotation and the third and fourth radials contact each end of a respective one of the drive recesses located most remotely from the axis of rotation.
• the angular distance between the first and second radials is greater than the angular distance between the third and fourth radials.
• a drive spline of circular configuration having an axis of rotation, with the drive spline having a plurality of drive recesses provided with replaceable drive surfaces along a first angular distance between a first and second radial, said drive surfaces extending axially along the drive spline.
• Figure 1 is a side diagrammatic view of a circular sawblade mounted on a drive spline which, in turn, is mounted on an arbor, the sawblade and drive spline having a configuration according to the invention;
• Figure 2 is a side diagrammatic enlarged view of a circular sawblade mounted on a drive spline and illustrating the drive configuration between the spline and the sawblade according to a first embodiment of the invention
• Figure 3 is an enlarged view of the circular sawblade of Figure 2;
• Figures 4A, 4B, 4C and 4D are enlarged views of four different drive spline configurations according to a further aspect of the invention;
• Figure 5 is an enlarged view of an insert according to a further aspect of the invention.
• a circular sawblade 10 is mounted on a drive spline 11 which, in turn, is mounted on an arbor 12.
• the arbor 12 is journalled in bearings 13 and a source of turning power for the arbor 12 is provided (not shown) which is then transferred to the sawblade 10 to turn the sawblade 10 and cut the wood diagrammatically illustrated at 14.
• a pair of sawguides 20 are mounted on either side of the circular sawblade 10. They guide the sawblade 10 and can move it axially on the drive spline 11. It will be appreciated, of course, that a plurality of sawblades could be mounted on the drive spline 11 depending on the lumber which is being cut and the desires of the operator.
• FIG. 2 illustrates the sawblade 10 mounted on the drive spline 11.
• the drive spline 11 and the sawblade 10 have a common axis of rotation 21 and, under operation, the sawblade 10 rotates clockwise as seen by the arrows.
• a series of inner driven surfaces 22 of the sawblade 10 are complementary to outer drive recesses 23 of the drive spline 11.
• the radially innermost distance 24 of the drive surface 22 is greater that the radially outermost distance 25 so that if the sawblade contacts a foreign object such as a spike in a tree being cut, the blade 10 will not be hurled from the drive spline 11, but will be retained by the drive spline 11 such that the operator may immediately terminate operation of the drive system.
• the outside circumference of the drive spline is indicated by a first diameter d m and the inside diameter of the drive spline is indicated by a second diameter d 2i .
• the distance between ⁇ and d 2i is the distance between the outer diameter of the drive spline 11 and the radially inwardmost distance of the drive recess 23.
• First and second radials r,, r 2 are drawn from the axis of rotation 21 to touch the ends of the drive recess 23 located radially most closely to the axis 21.
• Third and fourth radials r 3 , r 4 are drawn from the axis of rotation 21 to touch the ends of the drive recess 23 located radially most remotely from axis 21.
• the angular distance between r, and r 2 will be larger than the distance between r 3 and r 4 as can clearly be seen from Figures 2 and 3.
• the distance between the ends of the drive recess 23 located closest to the axis 21 is .597 in. as illustrated. This distance is obtained by drawing radials to each of the ends of the drive recess 23 and measuring the distance of .597 in.
• a 60 degree angle is cut into the drive spline 23 and a surface is formed 90 degrees to the line defining the distance of .597 in. which meets the 60 degree angle cut. This surface defines the most advanced point of the radial r, and the most retarded point of radial
• the drive surfaces 30 take a somewhat partially convex configuration and in Figure 4B, the drive surfaces 32 take on an appearance similar to the drive surfaces 22 of Figures 2 and 3 but extend inwardly a much greater distance. However, it remains the case that the angular distance ⁇ , between the radials r,, r 2 is less that the angular distance ⁇ 2 between the radials r 3 , r 4 .
• FIGS 4C and 4D illustrate two further drive configurations according to further aspects of the invention.
• a drive surface 40, 41 which has an angle ⁇ relative to radial r 3 which is greater than zero degrees.
• replaceable drive surfaces 34 are located along removable inserts made of hardened steel material 35 extending axially along the spline 11, and being secured to the drive spline with bolts 36.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Wood Science & Technology (AREA)
• Forests & Forestry (AREA)
• Sawing (AREA)
• Power Steering Mechanism (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Scissors And Nippers (AREA)
• Processing Of Stones Or Stones Resemblance Materials (AREA)

Applications Claiming Priority (5)

Publications (2)

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Family Applications (1)

Country Status (6)

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Family Cites Families (4)

• 1996
  • 1996-04-26 AU AU53943/96A patent/AU706706B2/en not_active Ceased
  • 1996-04-26 DE DE69618452T patent/DE69618452D1/de not_active Expired - Lifetime
  • 1996-04-26 EP EP96910874A patent/EP0822879B1/de not_active Expired - Lifetime
  • 1996-04-26 AT AT96910874T patent/ATE211666T1/de not_active IP Right Cessation
  • 1996-04-26 WO PCT/CA1996/000266 patent/WO1996033835A1/en active IP Right Grant
  • 1996-04-26 NZ NZ305825A patent/NZ305825A/en unknown

Non-Patent Citations (1)

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