This invention relates generally to sawing machines, band saws, including vertical band saws, and to assemblies that are used with such sawing machines and band saws. More specifically, this invention relates to a rotating blade guide assembly that is used to facilitate the mounting of a continuous blade onto the band wheels of a sawing machine and to capture a portion of the blade within the blade guide whereby the operator is then able to rotate a portion of the blade about 90° from its mounting position to a cutting position.
Many sawing machines and vertical band saws, in particular, have an endless band-like blade that is mounted about two substantially flat, co-planar band wheels. Typically, the band wheels are situated such that there is an upper band wheel that is positioned above a horizontal work surface and a lower band wheel that is positioned below the horizontal work surface. The blade is then tensioned such that the blade moves with and along a portion of the outer perimeter of the band wheels, the blade having a toothed cutting edge that is used to cut material or stock that is located at the horizontal work surface. This is well known in the art of sawing machines.
In the art of such sawing machines and blades for such machines, it is also known that it is advantageous to rotate a portion of the blade at the horizontal work surface by 90° or so. Materials being cut are generally produced in long lengths that must be cut into shorter lengths to produce stock for downstream manufacturing operations or finished parts. Rotating the blade 90° allows this “cross cut” operation to take place without the return strand of the blade interfering with the workpiece. Rotation is typically effected by means of stationary guide means located above and below the horizontal work surface.
In sawing machines of this type, it is also necessary to replace the band-like blade, or band, with another from time to time. This is accomplished by releasing the tension between the upper and the lower band wheels, then removing that portion of the band from within the stationary guide means and finally removing the band from the machine. To install a new band, the operator must position a portion of the band above the upper band wheel and along its perimeter, position another portion of the band below the lower band wheel and about its perimeter, partially tension the band, and then, by hand, twist a portion of the band at the horizontal working surface about 90° in order to place that portion of the band into the stationary guide assemblies one at a time. In the current art, this is done with some difficulty since, under full tension, it is too difficult to twist and insert the blade into the guides and, under partial or no tension, the blade tends to slip off of the band wheels due to the torque applied to the band by the twisting motion. The guide mechanism typically consists of two guide assemblies, one above the working surface and one below, each having a slot within which the band is inserted. Typically, the blade guide assemblies will include carbide guides that are used to support the sides of the blade and a carbide-faced pressure block that is used to support the back edge of the blade. In this fashion, the guide assemblies apply a slight, forward pre-load to the band blade which effectively reduces noise and vibration during cutting. Once the band is in place, the band is properly tensioned and the sawing machine is ready for cutting.
In the view of this inventor, what is needed is an assembly that provides a blade guide that is rotatable such that the band can be placed about the band wheels and then, with the band in that position, the band can also be placed into the blade guide. The blade guide, with the band placed within it, can then be simply rotated by hand using the integral torque arm under full band tension such that the desired cutting position of the blade is accomplished, as described above. What is also needed is a way to effectively secure the rotated blade guide in its rotated position for proper cutting. What is also needed is a way to provide two such rotating blade guide assemblies such that one can be located above the working surface and one below it. What is also needed is such a blade guide assembly that also guides and supports the band during normal use by using any variety of guiding means of current manufacture that can be built into, or used with, the rotating blade guide assembly of the present invention.
The present invention provides for a rotating blade guide assembly that includes a blade guide carrier and means for rotating the blade guide carrier from a first position to a second position. The first position would be that blade orientation when the blade is initially placed about the band wheels. The second position would be the blade orientation when the blade is rotated about 90° to its cutting position. In this way, the orientation of the sawing machine blade is changed when the blade guide carrier is rotated from the first position to the second position, thus avoiding the need to do so by hand. The rotating blade guide assembly of the present invention further provides means for securing the blade guide carrier in the second position so as to prevent rotation of the blade guide carrier during use of the sawing machine.
The foregoing and other features of the rotating blade guide assembly of the present invention will be apparent from the detailed description that follows.
Referring now to the drawings in detail, wherein like numbers represent like elements throughout,
As shown in
Referring now to
Referring now specifically to
In the embodiment disclosed and illustrated herein, it will be seen that the bottom portion 32 of the blade guide carrier 30 includes an aperture 31 and a front face 33. The front face 33 extends upwardly in a plane along the central portion 34 of the blade guide carrier 30 as well. Opposite the front face 33 of the central portion 34, and to the rear thereof, is a substantially cylindrically-shaped outer arcuate surface 35. At the uppermost portion of the front face 33, and extending forwardly of the front face 33 of the central portion 34 of the blade guide carrier 30, is a pair of shoulder members 36. The shoulder members 36 are separated by a slot 76. The upper portion 38 of the blade guide carrier 30 also includes a substantially cylindrically-shaped outer arcuate surface 37 and a flat top portion 39. The slot 76 between the shoulder portions 36 extends upwardly through the upper portion 38 of the blade guide carrier 30. The front face 33 of the blade guide carrier 30 further includes a first counter-bore 71, the first counter-bore 71 being a generally circular structure and having an axially-aligned aperture 72. The front face 33 also includes a second counter-bore 73 and an aperture 74. The function and purpose of both counter-bores 71, 73 and apertures 72, 74 will be apparent later in this detailed description. In this embodiment, the blade guide carrier 30 includes another vertically-disposed slot 77, the purpose of which is to carry a pressure block (not shown) against a blade 7 situated within the assembly 10. The pressure block would be movable by means of an eccentric fastener 79 (see
Referring back to
The first forwardly-extending guide arm member 14 further includes a bottom flat surface 13 that is intended to rest against the shoulders 36 of the blade guide carrier 30. Disposed at the top surface 39 of the blade guide carrier 30 is a cap 40. The cap 40 includes a centrally-disposed slot 42 and is secured or attached to the upper portion 38 of the blade guide carrier 30 by means of fasteners 44. The slot 42 of the cap 40 substantially matches the dimensioning of the slot 76 that is defined within the blade guide carrier 30. When used as intended, a portion of the band saw blade 7 passes through the slot 42 of the cap 40 and also through the slot 76 of the blade guide carrier 30. In this regard, and when comparing
Referring again to
Extending upwardly from the fork 50 is shaft 56 and a handle 58. A portion of the shaft 56 is receivable within a spring clip 60 that is attached to the first forwardly-extending guide arm member 14 of the guide arm 12. The fork 50 allows the operator to apply torque to the blade guide carrier 30 to effect rotation of the carrier 30 within the upper guide rotation assembly 10 when the assembly 10 is used as intended. The spring clip 60 allows the handle 58 to be secured when the assembly 10 is in position where the blade 7 can be used to cut stock. The fork members 52, 54 effectively “straddle” an extension member 62 having a drive screw 64 which is provided to allow for fine adjustment of the guide rotation assembly 10 as may be desired or required. The length of the drive screw 64 is equal to the distance between the inner surfaces of the fork members 52, 54 providing accurate rotational location of the carrier 30 when the fork 50, and the handle 58 are rotated upward into the locked position.
The upper guide rotation assembly 10 also includes a pair of blade guides 91, 93 that are attached to the central portion 34 of the blade guide carrier 30 by means of fasteners 92, 94 respectively. It should be noted that the blade guides 91, 93 are functionally adapted to be held within the counter-bores 71, 73 that are defined within the central portion 34 of the blade guide carrier 30. It should also be noted that the fasteners 92, 94 are receivable within the apertures 72, 74 also defined within the central portion 34 of the blade guide carrier 30 to retain the blade guides 91, 93 respectively, within the counter-bores 71, 73, respectively. It should also be noted that the aperture 72 to one side of the central portion 34 of the blade guide carrier 30 is located somewhat higher than its counterpart aperture 74 to the other side of the central portion 34 of the blade guide carrier 30. The purpose and functionality of this arrangement will be apparent later in this detailed description. However, it is again to be noted that the positioning and use of the particular blade guides 91, 93 described is for purposes of explanation only, the invention not being limited to the specific blade guide arrangement described herein. Other blade guide arrangements could be used without deviating from the scope of the present invention.
Referring now to
It is to be understood that the lower guide rotation assembly 110, as is illustrated in
In application, it will be assumed that the operator needs to install a new blade 7 into the sawing machine 1. It will also be assumed that the upper guide rotation assembly 10 has been left in the position it would normally be in following removal of the blade 7 that was last used in the sawing machine 1. That position would be as is illustrated in
With the blade 7 inserted as described above, and the blade 7 fully tensioned, the handle 56, 58 and fork 50 are rotated to the position shown in
Although a preferred embodiment of the invention has been disclosed above, it will be understood that modifications may be made within the spirit and scope of the invention. Accordingly, it is intended that the invention no be limited by the foregoing description but solely by the scope of the appended claims.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US06/11066 | 3/24/2006 | WO | 00 | 9/22/2008 |