177results about "Strap saws" patented technology

Band saws with high-speed safety systems are disclosed. The band saws include a detection system adapted to detect a dangerous condition between a blade and a person. A reaction system performs a specified action such as stopping the blade upon detection of the dangerous condition.

A safety system for a rotary saw or other dangerous machine tools features a flesh-sensing circuit (14, 19), located on a safety guard (16) surrounding a dangerous machine part, which generates an electronic signal to trigger emergency stopping of the machine before the operator can contact the dangerous machine part. The stopping means preferably employs DC injection, winding current direction reversal and/or electromagnetic motor braking, in the event of detection of operator contact with the safety guarding device. The system is adapted to be used both with newly-manufactured machine tools and by retrofitting onto previously-manufactured machine tools, by in-the-field modifications.

This invention is directed toward a system for driving a wire loop cutting element. More particularly, the disclosed invention employs a frame and pulleys to drive a wire loop cutting element.

A retaining assembly is provided for a tensioning arrangement for adjusting the tension of the cutting chain in the chain saw. The retaining assembly includes a rotatable knob that operates in conjunction with the chain saw's engine chassis, clutch cover, and guide bar and is rotatable about an axis of rotation between a tightening position for holding the guide bar in place and a loosening position enabling the guide bar to be repositioned whereby the tension in the cutting chain is adjusted. A locking mechanism is provided for locking and unlocking the knob for rotational movement. When the locking mechanism is in a locking position, moveable engagement points of the locking mechanism extended beyond the confines of the knob and engage fixed engagement points. When the locking mechanism is in the unlocking position, the moveable engagement points, having moved inwardly of the confines of the knob, are disengaged from the fixed engagement points.

A method and arrangement for adjusting a feed rate of a crosscut saw (1), in particular, in a harvesting head of a forest machine during the crosscutting of wood (9) in the apparatus. A feed force (F) of the crosscut saw and/or a rotating rate (v_chain) of a cutter chain (5) revolving around a guide bar (4) are thus controlled. The control is implemented such that first the feed rate (v_feed) of the crosscut saw (1) is measured at given intervals. By adjusting thereafter the feed force of the actuator (2) controlling the crosscut saw and/or the rotating rate (v_chain) of the cutter chain (5) and by determining the effect of the performed adjustment on the feed rate of the crosscut saw any change (δv) in the feed rate and the most advantageous adjustment measure to be performed next is concluded.

Apparatus and methods for operational support and guidance of pivoting movement of portable band saws are disclosed. The apparatus includes a pivoting mount maintained at a work surface. A support is connected with the mount and includes a forward bracket adjacent to the mount for receiving a front portion of a blade housing structure of the portable band saw. An extension bar of the support supports a rear portion of the blade housing structure, a securing latch at the extension provided to releasably maintain the rear portion of the blade housing structure supported thereat.

An end-dogging head saw is disclosed comprising a log cradle for supporting a log, a log-turning device for rotating the log into proper alignment with a pair of band saws, the log-turning device depending from overhead log carriages which move the log into contact with the band saws, and a carriage drive for powering the overhead log carriages, whereby short logs can be quickly and efficiently processed. The invention also seeks to provide a method for using the apparatus, comprising rotation of a log through 360 degrees to allow for cutting at any desired angle along the length of the log. The method allows for maximal recovery of high-quality lumber.

A saw for cutting a cant by sensing the curvature of the cant and raising or lowering the saw blade in order to follow the curvature when cutting the cant.

The chain of an electromotive chain saw is quickly stopped by the combined use of an electric brake and a mechanical brake when a trigger member is turned off. The rear end of a brake band disposed to tighten a brake drum by operating a hand guard is secured to a bent rod. When the trigger member is released, the brake band is normally tightened around the outer periphery of a brake drum by the urging force of a coil spring. When the trigger member is released, a circuit provided with a brake winding is closed, thereby applying a dynamic braking force. When the dynamic brake force is applied, a centrifugal clutch is released quickly and the speed of stopping the brake drum is accelerated.

A hand-held power tool includes a housing having an opening, first and second wheels supported by the housing for rotation about respective first and second parallel axes, a continuous saw blade supported by the first and second wheels, a first guide roller set coupled to the housing proximate a first side of the opening, and a second guide roller set coupled to the housing proximate a second side of the opening. The first and second wheels define respective first and second facing, parallel planes containing the first and second axes. The first and second guide roller sets define respective third and fourth facing, parallel planes that are also parallel to the first and second planes. A first dimension between the first plane and the third plane is less than about 3.3 inches. A second dimension between the second plane and the fourth plane is less than about 3.3 inches.

A radial sawing method for cutting a log into six sections. Each resulting section has a triangular wedge shape, such that in cross-section, an angle of approximately sixty-degrees (60°) at the interior edge of the log section is formed. The approximately 60° angle can be the point of an equilateral triangle. After the log has been formed into six pieces that are relatively equivalent in size and shape, each respective piece can then be fed into additional sawing machines for additional processing, such as to form symmetrically shaped pieces, include a circle, a square, a hexagon, an octagon, or other polygon pieces.

In a band saw machine in which a pair of guide posts (7L, 7R) for guiding a saw blade housing that rotatably supports a driving wheel (17) and a driven wheel (21) and can vertically move in the vertical direction are provided between the driving wheel (17) and the driven wheel (21), an upper traveling part (23U) of a band saw blade (23) is disposed in the rear of the guide posts (7L, 7R) and a lower traveling part (23L) of a band saw blade (23U) is disposed in front of the guide posts (7L, 7R), when the band saw machine is viewed from the side, an intersection point between centers of the both wheels (17, 21) and the center line of the wheel width is almost equal to the width of the guide posts (7L, 7R).

The present invention relates to a safety device for portable tool with a heat engine that is capable of stopping, almost instantly, the operation of said tool after unexpected, sudden, and violent movements, said device including at least one electronic accelerometer (5) enabling the measurement of the acceleration along at least one plane or axis (X, Y, Z), the output(s) of said accelerometer (5) being connected to an electric and/or electronic monitoring means (7), wherein said electric and/or electronic monitoring means consists of an electric and/or electronic management card (7), the latter and the accelerometer being supplied with electric voltage by an electric current generator (9) known per se and actuated by the heat engine, said electric and/or electronic management card being configured to process analog or digital electrical data from the accelerometer and activate a means ensuring that said heat engine stops almost instantly.

A multi-bandsaw machine includes several bandsaws, for cutting a material into a plurality of plates in a single process. At least one side edge of each bandsaw has a plurality of diamond grits, and the bandsaws rotate in a single direction on the multi-bandsaw machine, so as to cut the material with the diamond grits and form a cutting notch on the material. The cutting notch has a depth to kerf ratio at least larger than 100:1 during the process of cutting the material with the diamond grits in each hour.