Band saw apparatus with blade tensioner and related method

A tensioner assembly comprising:

• a mounting bushing having an opening therethrough;
• a shaft having at least one threaded region along its axial length, said shaft extending through said opening in said mounting bushing and sized for movement of said shaft through said opening;
• a mounting nut threaded onto said threaded region of said shaft and spaced from said mounting bushing, said mounting nut and said shaft being rotatable relative to one another to cause a corresponding relative axial movement between said mounting nut and said shaft;
• a spring disposed around said shaft and positioned between said mounting bushing and said mounting nut, a first end of said spring positioned against a seating surface located intermediate said mounting bushing and said mounting nut such that said first end of said spring is spaced from said mounting nut, a second end of said spring positioned against a first side of said mounting bushing;
• and
• a handle connected to said shaft and positioned to a second side of said mounting bushing for rotating said shaft.

A tensioner assembly comprising:

• a mounting bushing having an opening therethrough;
• a shaft having at least one threaded region along its axial length, said shaft extending through said opening in said mounting bushing;
• a mounting nut threaded onto said threaded region of said shaft and spaced from said mounting bushing;
• a seating surface extending from said shaft at a fixed position along said shaft and intermediate said mounting bushing and said mounting nut;
• a spring disposed around said shaft and positioned between said mounting bushing and said seating surface, a first end of said spring positioned against said seating surface so as to be fixed at said intermediate position along said shaft regardless of a distance between said mounting bushing and said mounting nut, a second end of said spring positioned toward said mounting bushing;
• a handle positioned to a second side of said mounting bushing for rotating said shaft;
• wherein said assembly is positionable in a non-tensioning configuration establishing a first distance between said seating surface and said mounting bushing and a second distance between said handle and said mounting bushing;
• wherein said assembly is positionable in a tensioning configuration establishing a third distance between said seating surface and said mounting bushing and a fourth distance between said handle and said mounting bushing, said third distance being less than said first distance and said fourth distance being greater than said second distance;
• and
• wherein a compression force of said spring in said tensioning configuration is greater than a compression force of said spring in said non-tensioning configuration.

A band saw apparatus including a blade under tension, comprising:

• a frame;
• a drive mount including a first portion pivotably connected to said frame;
• a rotatable wheel supported by said drive mount and movable therewith, the blade extending about said rotatable wheel;
• a tensioner assembly including:
• a mounting bushing having an opening therethrough, said mounting bushing connected to a second portion of said frame;
• a shaft having at least one threaded region along its axial length, said shaft extending through said opening in said mounting bushing;
• a mounting nut threaded onto said threaded region of said shaft and spaced from said mounting bushing, said shaft being rotatable relative to said mounting nut, said mounting nut connected to support said drive mount;
• a spring disposed around said shaft and positioned between said mounting bushing and said mounting nut, a first end of said spring positioned against a seating surface located intermediate said mounting bushing and said mounting nut such that said first end of said spring is spaced from said mounting nut, a second end of said spring positioned toward said mounting bushing, said spring being compressed from its normal state;
• a handle connected to said shaft and positioned to a second side of said mounting bushing for rotating said shaft, said handle being spaced from said mounting bushing;
• and
• wherein a tension force on the blade is proportional to a compressive force of said spring.

A method of tensioning a blade of a band saw apparatus including a frame, a drive mount including a first portion pivotably connected to the frame, a rotatable wheel supported by the drive mount and movable therewith, the blade extending about said rotatable wheel, the method including the steps of:

• (a) providing a tension bolt assembly including a mounting bushing having an opening therethrough, a shaft extending through the opening and having at least one threaded region along its axial length, a mounting nut threaded onto the threaded region of the shaft and spaced from the mounting bushing, a spring disposed around the shaft and positioned between the mounting bushing and the mounting nut, a first end of the spring positioned against a seating surface located intermediate the mounting bushing and the mounting nut such that said first end of said spring is spaced from the mounting nut, a second end of the spring positioned toward a first side of the mounting bushing;
• (b) connecting the mounting bushing to the frame;
• (c) connecting the mounting nut to a second portion of the drive mount;
• d) rotating the shaft until the shaft moves through the mounting bushing opening and the spring is compressed.

A tensioner assembly comprising:

• a mounting bushing having an opening therethrough;
• a rotatable shaft having at least one threaded region along its axial length, said shaft extending through said opening in said mounting bushing;
• a mounting nut threaded onto said threaded region of said shaft and spaced from said mounting bushing;
• a seating surface extending from said shaft at a position intermediate said mounting bushing and said mounting nut;
• and
• a spring disposed around said shaft and positioned between said mounting bushing and said seating surface, a first end of said spring positioned against said seating surface so as to be fixed at said intermediate position along said shaft regardless of a distance between said mounting bushing and said mounting nut, a second end of said spring positioned toward said mounting bushing.