CA2255791C - Rotatable saw apparatus - Google Patents
Rotatable saw apparatus Download PDFInfo
- Publication number
- CA2255791C CA2255791C CA 2255791 CA2255791A CA2255791C CA 2255791 C CA2255791 C CA 2255791C CA 2255791 CA2255791 CA 2255791 CA 2255791 A CA2255791 A CA 2255791A CA 2255791 C CA2255791 C CA 2255791C
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- CA
- Canada
- Prior art keywords
- arm member
- saw
- pulley means
- drive
- pulley
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- 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
- B23D47/00—Sawing machines or sawing devices working with circular saw blades, characterised only by constructional features of particular parts
- B23D47/12—Sawing machines or sawing devices working with circular saw blades, characterised only by constructional features of particular parts of drives for circular saw blades
-
- 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
- B23D45/00—Sawing machines or sawing devices with circular saw blades or with friction saw discs
- B23D45/10—Sawing machines or sawing devices with circular saw blades or with friction saw discs with a plurality of circular saw blades
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- 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
- B27B5/16—Saw benches
- B27B5/18—Saw benches with feedable circular saw blade, e.g. arranged on a carriage
- B27B5/185—Saw benches with feedable circular saw blade, e.g. arranged on a carriage the saw blade being carried by a pivoted lever
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Sawing (AREA)
Abstract
A high speed rotatable saw apparatus is provided having a machine frame, an arm member rotationally mounted on the machine frame, a saw rotatably mounted on the arm member a driven pulley rotatably mounted on the arm member and being rotatably connected to the saw, a drive pulley drivingly connected to a motor, the drive pulley being disposed at a location spaced apart from the arm member, and an intermediate pulley disposed intermediate the drive pulley and the driven pulley, the intermediate pulley being configured and disposed such that its axis of rotation is co-axially aligned with the rotational axis of the arm member, the rotatable saw apparatus further comprising a displacement mechanism for high speed, rotationally, reciprocally displacement of the arm member about the rotational axis of the arm member such that the saw is rotationally displaceable between a first position and a second position, a continuous driving means which simultaneously, drivingly connects each of the drive pulley, the intermediate pulley and the driven pulley, wherein, when the saw is displaced between the first position and the second position, the driving means remains at a constant tension.
Description
ROTATABLE SAW APPARATUS
BACKGROUND OF THE INVENTION
The present invention relates to the field of industrial saws and more particularly to the field of saws having an articulated, pivotable or rotatable arm, such as swing saws, which may be used in saw mills for cutting logs and other lumber.
Swing saws for use in the lumber industry are known, for example US Patent no.5,094,654 to Strom.
However known swing saws are characterised by certain limitation and disadvantages. For example, known swing saws, are very heavy, which can severely limits the displacement speed of the their rotatable arm, and therefore, their speed of operation. Alternatively, known swing saws may require a very powerful motor to effect the displacement of their rotatable arm in order to compensated for their excessive weight. The excessive mass of the rotatable arm of known swing saws may be due to a number of reasons, such as for example, their long or excessive length, or the weight of the heavy mechanical components of their drive mechanisms. Further, rotatable saw arms known in the prior also have the motor driving the saw mounted or installed directly on the rotatable arm itself, thus needlessly adding a very large mass which must be displaced with each movement of the saw arm.
Prior attempts at overcoming said problems resulted in unsatisfactory results.
For example, moving the motor off the rotatable arm caused the tension of their drive mechanisms, such as a drive belt, to vary through the movement of the rotatable arm. This was due to the fact that the radius of curvature of the rotatable arm was different than the radius of curvature of the drive belt. The unwanted variation in the tension of the belt drive mechanisms was undesirable from an operational view point, because it caused temporary loss of power to the saw, and unwanted variations in the power available to the saw, i.e. there were peaks and valleys in the power output.. Further, the S variation in the tension in the drive belt caused premature wear of the drive belt.
Known swing arms are also configured such that they are pivotably displaced about one of their extremities, thus requiring a large force, and therefore a large motor to effect the displacement thereof.
The low operational speed and efficiency of known swing saws, the undesirable variation in the tension in the drive belt, and the requirement for large motors make known saws inefficient to operate, more expensive to build, and therefore they do not meet with commercial success.
Therefore, it would be advantageous to provide a rotatable saw apparatus wherein the saw is driven by a constant tension driving means, wherein the tension in the drive belt does not vary as the saw arm is rotated about its axis of rotation.
It would be further advantageous to provide a rotatable saw apparatus wherein the motor is not disposed on the saw arm itself.
It would be further advantageous to provide a rotatable saw apparatus having a very high speed of operation.
It would be further advantageous to provide a rotatable saw apparatus wherein the saw is driven from the drive motor through a continuous drive belt, wherein the pivoting of the arm of the rotatable saw apparatus does not cause a lengthening or shortening of said belt drive means, therefore keeping the tension of said drive belt constant.
It would be further advantageous to provide a rotatable saw apparatus wherein the rotational displacement of the arm is effected by a pneumatic piston.
It would be further advantageous to provide a rotatable saw apparatus wherein the saw arm is configured and disposed such that its axis of rotation acts as a fulcrum and takes advantage of the lever effect, thus requiring a reduced force to rotationally displace the saw arm.
SUIVFVIARY OF THE INVENTION
The present invention, in accordance with one aspect provides for a rotatable saw apparatus comprising a machine frame, an arm member, said arm member being pivotably mounted on said machine frame such that said arm member is pivotable about a pivot axis a circular saw rotatably mounted on said arm member a displacement mechanism a drive belt means a pulley drive component for inducing rotation of said saw comprising a driven pulley means, a drive pulley means and an intermediate pulley means, said driven pulley means being rotatably mounted on said arm member and connected to said saw for the rotation thereof, said drive pulley means being drivingly connected to a motor, said drive pulley means being disposed at a location spaced apart. from said arm member, said intermediate pulley means being disposed 2 0 intermediate said drive pulley means and said driven pulley means, said displacement mechanism being connected to said arm member such that said displacement mechanism is able to pivotally displace: said arm member about said pivot axis of said arm member such that said saw is displaceable between a first position and a second position, said drive belt means having a first end and a second end, said first end engaging said drive pulley 2 5 means, said second end engaging said driven pulley means, said drive belt means defining a first flight side and an opposed second flight side, said first and second flight sides each being connected respectively to said first and second ends, said drive belt means simultaneously engaging said drive pulley means, said intermediate pulley means and said driven pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second positions, said intermediate pulley means having a diameter larger than the diameter of the drive pulley means and of the driven pulley means.
In accordance with another aspect the present invention provides a rotatable saw apparatus comprising a machine frame, an arm member, said arm member being pivotably mounted on said machine frame such that said arm member is pivotable about a pivot axis a circular saw rotatably mounted on said arm member a driven pulley means rotatably mounted on said arm member and connected to said saw for the rotation thereof a drive pulley means drivingly connected to a motor, said drive pulley being disposed at a location spaced apart from said arm member, an intermediate pulley means disposed intermediate said drive pulley means and said driven pulley means, said intermediate pulley means being configured and disposed such that its axis of rotation is co-axially aligned with said pivot axis of said arm member a displacement mechanism and a drive belt means said displacement mechanism being connected to said arm member such that said displacement 2 0 mechanism is able to pivotally displace said arm member about said pivot axis of said arm member such that said saw is displaceable between a first position and a second position, said drive belt means having a first end and a second end, said first end engaging said drive pulley means, said second end engaging said driven pulley means, said drive belt means defining a first flight side and an opposed second flight side, said first and second flight sides each being connected 2 5 respectively to said first and second ends, said drive belt means simultaneously engaging said drive pulley means, said intermediate pulley means and said driven pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second positions, said arm member having opposed first and second arm ends, said pivot axis being disposed between said first and second arm ends so as to divide the arm member into a first side terminating in said S
first arm end and a second side terminating in said second arm end, said saw being mounted to said first side of the arm member and said dlisplacement mechanism being connected to said second side of the arm member.
In accordance with the present invention a rotatable saw apparatus may comprise an arm member having a saw rotationally mounted thereon, which saw may so be driven by a drive belt means so as to facilitate a constant tension thereof. The arm member is to be chosen so as to be of sufficiently sturdy construction so as to be able to withstand the rigours of an industrial application, such as for example, a saw mill. The arm member may be configured in any known manner, and __ _.
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-_.__.____.____________ Sa may for example comprise a hollow steel member of, for example, round or square shape, or may comprise spaced apart steel plates, connected together by intermediate spacer(s). In accordance with a particular embodiment, the arm member may be configured so as meet operational parameters, for example, such as deflection, serviceability, etc... yet be as light as possible in order to allow for the high operational speeds required, i.e. the high speed of displacement of the arm member, that is desired to be achieved.
The arm member may have a generally elongated configuration comprising a longitudinal axis, and may further comprise opposed first and second ends. The saw member may have a saw rotatably mounted adjacent the first opposed end, and said saw may be configured and disposed to cut logs, lumber, etc... The logs or lumber to be cut may be advanced or placed into position for cutting adjacent the saw through a feeding system. The saw may be any type of industrial saw suitable for lumber mill or saw mill operation, for example, a circular saw. Different diameter saws may be mounted on the arm member, depending on the application or operating conditions. It is understood that the saw may be suitable for clockwise or counter clockwise operation.
The arm member may pivotably (i.e. be rotatably) connected (i.e. hinged, pinned, pivoted, etc...) such that it may pivot about a pivot axis. In accordance with a general aspect, the pivot axis may be at right angle to the longitudinal axis of the arm member. The location of the axis about which the 2 0 arm member may be pivoted may be such so as to minimize the forces required to rotate said arm member (and saw), and therefore reduce the horsepower of the motor required to operate the displacement of the arm member. Alternatively, the location of the pivot axis may be such so as to increase the speed and operational efficiency of the rotatable saw apparatus.
As may be understood, the rotatable saw apparatus of the present invention may be configured and disposed to achieve high 2 5 operational velocities, i.e. wherein the velocity of the rotational displacement of the arm member is to be maximized. Thus, the length of he arm member may be minimized as much as possible in order to reduce the mass thereof to be displaced. Further, the arm member may be pivoted about a pivot axis disposed such as to maximize the lever effect of the arm member on the saw. The pivot axis, i.e. the point about which the arm member is rotated, may act as a fulcrum, in order to maximize the effect of the applied force necessary to rotate the arm member.
Therefore, in accordance with one aspect, the pivot axis of the arm member may be adjacent its second opposed end, and the force necessary to cause the rotation of the arm member may be applied between the second opposed end of the arm member and the pivot axis. In accordance with the present invention, the pivot axis of the arm member may be spaced apart from the second opposed end of the arm member. In accordance with the present invention, the pivot axis of rotation may be disposed adjacent the middle point of the arm member, and the force necessary to cause the rotation of the arm member may be applied at or near the second opposed end of the arm member.
In accordance with yet a further embodiment, the force necessary to cause the rotation of the arm member may be applied at a point intermediate the pivot axis and the first opposed end of the arm member.
It is understood that the saw member is to be supported on (i.e. rotatably mounted or connected to) a machine frame (i.e. or structure) which machine frame may form part of the rotatable saw apparatus as a whole, or may be a stand-alone structure. As may be understood, the frame may be constructed in accordance with known industrial machinery practices, and may comprise the necessary controls, wiring, switches, bearings, bushings, and other components necessary for its intended operation.
As mentioned above, the arm member may be rotationally connected to a machine frame such that 2 0 it may be rotatable about a rotational axis. The rotational connection of the arm member may be such that the first opposed end of the saw arm, and the saw rotationally mounted at or adj acent said opposed first end, may be rotatably displaceable from a first (i.e. lower) position, to a second (i.e.
higher) position. The rotational displacement of the first opposed end and of the saw may be in the (approximate) shape of an arc of a circle. As may be understood, the rotational displacement of the 2 5 saw may be effected such that, for example, when being displaced towards the first (i.e. lower) position, the (rotating) saw may be brought into contact with a piece of lumber to be cut. The rotational displacement from the first to the second position may be reversed, and the reciprocating cycle may be repeated any number of times. It is understood that the displacement of the saw in one or both directions (i.e. the distance travelled) may be varied in accordance with operational conditions, or in accordance with the particular piece of lumber to be cut.
The rotatable saw apparatus may further comprise a displacement mechanism configured and disposed so as to apply a reciprocal force to the arm member so as to effect the displacement of the arm member about its pivot axis, as explained above. The displacement mechanism may comprise a number of components, including a pneumatic piston to power the displacement mechanism. It is understood that any other type of force generating means, such as an electric motor, hydraulic piston, etc... may be used to power the displacement mechanism. The displacement mechanism may comprise a force transfer member operationally connected to the pneumatic piston, which is hingedly connected to the arm member. Therefore, the force transfer member may, for example, be hingedly connected to the arm member between the pivot axis and the second opposed end, or even at the second opposed end. The pneumatic piston or cylinder may therefore impart, through the force transfer member, a force in one direction, (for example, downwardly) at or near the second opposed end of the arm member, causing the first opposed end to be rotated upwardly, i.e. towards its second position. Following this, the pneumatic piston may impart, again through the force transfer member, a force in another direction, i.e. for example, upwardly at or near the second opposed end, causing the first opposed end of the arm member to be rotated downwardly, i.e. towards its first position.
This reciprocal, up and down cycle may be repeated any number of times. For example, the pneumatic cylinder may cause the arm member to effect 240 cycles per minute, through a 2 0 displacement of 5 inches, (i.e. a 5 inch displacement in one direction, followed by a 5 inch displacement in another direction).
In accordance with the present invention, there is provided for a driven pulley which may be rotatably mounted to the arm member, and which may be disposed at or near the first opposed end 2 5 thereof. Said driven pulley may be rotatably connected to said saw through direct means, i.e. for example, the driven pulley and the saw may each be affixed to a (common) shaft, which common shaft may be supported by the arm member through friction reducing means, i.e.
such as bearings, bushings, etc.... Alternatively, the driven pulley may be rotatably connected to the saw through indirect means, i.e. through gears, etc..., in which case each of the driven pulley and the saw may be mounted to the arm member through appropriate connections, and each may be provided with appropriate anti friction means.
The present invention, further comprises a drive pulley which may be operationally connected to a motor means, such as for example, an electric motor. It is to be understood that the drive pulley is not to be supported on the arm member, but is to be disposed at a location spaced apart from the saw member, i.e. for example, it is to be supported opposite the second opposed end of the arm member. In accordance with a particular embodiment, the respective axis of rotation of the drive pulley and of the driven pulley may be disposed so as to be parallel to each other. Further the drive pulley and the driven pulley may be oriented in relation to the arm member such that each of the drive pulley and the driven pulley may rotate in a common plane. The drive pulley may be supported by the machine frame of the rotatable saw apparatus, or alternatively, may be supported otherwise, but in any event, not by the arm member. As may be understood, the drive pulley may comprised necessary friction reducing means, i.e. bearings, and other components, to effect its intended purpose.
As mentioned above, the drive pulley may be operationally connected to a motor means, such as for example, an electric motor, hydraulic motor, internal combustion engine, etc... The motor is to be disposed such that it is not supported on the arm member, but is instead supported (attached, 2 0 anchored, etc) at a location spaced apart from the arm member. For example, the motor may be supported by the machine frame of the rotatable saw apparatus, or alternatively, the motor may be supported by another structure. In any event, the motor is not to be supported onto or by the arm member. As may be understood, the motor may comprise the necessary controls, switches, etc... to effect its intended purpose. In accordance with a particular embodiment, the motor may comprise 2 5 an electric motor, of for example 3 to 15 horsepower, which motor may be anchored to the frame of the rotatable saw apparatus. The motor may be configured and disposed such that its power output shaft may be the shaft onto which the drive pulley is directly affixed. In this configuration, the motor may be anchored to the machine frame, and disposed so as to behind the arm member, i.e. adj acent the second opposed end, but remote from the first opposed end, with its output shaft disposed parallel to the axis of rotation of the driven pulley. Further, the configuration of the motor is to be such that its power output shaft be disposed such that the drive pulley affixed thereon may rotate in the same plane as the driven pulley. Alternatively, the power output shaft of the motor, and the shaft of the drive pulley may be indirectly connected through gears, a gear box, etc...
In addition to the drive pulley and the driven pulley, the present invention further provides for an intermediate pulley. The intermediate pulley may be disposed intermediate said drive pulley and said driven pulley, wherein the axis of rotation of each of the three pulleys may be parallel to each other, and such that each of the drive pulley, the driven pulley and the intermediate pulley may rotate in a common plane. As may be understood, the configuration and disposition of the drive pulley, the intermediate pulley and of the driven pulley is to be such that all three pulleys may be driven by one single driving belt mechanism, i.e. such as for example, a drive belt, chain, etc....
Thus, a single drive belt may simultaneously, drivingly connect the three pulleys. The drive belt may therefore be imparted with rotational force by the drive pulley, and be made to rotate, such that the upper flight of the drive belt may touch and pass over the upper edge of the intermediate pulley, continue towards the driven pulley, impart the driven pulley with rotational force, and then return towards the drive pulley, with its lower flight touching and passing under the intermediate pulley.
It is understood that the drive pulley, the intermediate pulley, and the driven pulley may be driven 2 o by more than one drive belt, for example two or more drive belts. In this configuration, each of hte individual drive belts may drive each of the three pulleys, and the two or more drive belts may be disposed besides one another, i.e. adj acent each other. In this configuration, each of the drive pulley, the driven pulley and the intermediate pulley may comprise a plurality of parallel grooves, each of which may be adapted to accept therein a drive belt. In an alternative configuration, the drive belts) 2 5 may be replaced by chain(s), in which case the pulleys may also comprise sprockets to engage with the chain(s), i.e. the drive means may comprise chain(s).
The intermediate pulley may be configured and disposed such that the axis of rotation of said intermediate pulley may be coaxially aligned with the axis of rotational of the arm member. Thus, as may be understood, the intermediate pulley may be rotational mounted on a shaft which is supported on a stand-alone support, or which shaft may be supported by the machine frame itself.
The intermediate pulley may alternatively be supported by the arm member itself, namely, that a shaft may be mounted on the arm member, and onto which shaft the intermediate pulley is rotationally mounted. In accordance with yet another particular embodiment, the intermediate pulley and the arm member may each be rotationally mounted on a common shaft, which shaft may be supported by the machine frame. As may be understood, in accordance with this particular embodiment, as the intermediate pulley and the arm member are each rotationally mounted on the same shaft, their respective axis of rotation will necessarily be co-axially aligned. It is understood that co-axially aligned may not mean exactly co-axially aligned, but may allow for some variation from a perfect co-alignment.
It is understood that in accordance with this configuration, (i.e. wherein the pivot axis of the intermediate pulley is coaxially aligned with the pivot axis of the arm member), the displacement of the saw from a first to a second position defines a first sector (i.e. a sector is defined as the geometric figure bounded by two equal radii and the included arc of a circle, which equal radii meet at the apex). Further, the displacement of the driven pulley from a first to a second position defines a second sector. It is to be understood that the first sector and the second sector may have the same apex, i.e their respective apex overlap. Therefore, there may be no relative displacement (axially or 2 o otherwise) between the saw and the driven pulley as they are displaced from a first to a second position, and therefore there may be no increase or decrease in the distance that the drive belt has to travel. Consequently, there may be no corresponding increase or decrease in the tension in the belt. Thus as may be understood, the geometry, i.e. the disposition of the components of the rotatable saw apparatus may be such that the rotational displacement of the saw from a first to a 2 5 second position may not cause a change in the tension of the drive belt.
It is to be understood, however, that the tension in the drive belt may by subject to some (minor) variations caused by operational loading thereon, i.e. when the saw is brought into contact with the log, the increased resistance brought to bear on the saw may cause some change in the tension of the drive belt. Further, a new drive belt may normally loose some of its tension soon after it is first put into operation.
In accordance with the present invention, the intermediate pulley may be sized such that the drive belt means (e.g. belt, or chain, etc...) which connects the drive pulley, the intermediate pulley and the driven pulley may always be in contact with the upper and lower surfaces of the intermediate pulley. Thus in accordance with this embodiment, the intermediate pulley may be oversized, i.e.
may be of a large diameter, for example, of a larger diameter than either the drive pulley or the driven pulley. The size of the diameter of the intermediate pulley may be combination of a number of factors, such as the vertical travel of the saw, the length of the arm member, the disposition of the drive pulley, etc...
In accordance with a further embodiment of the present invention, there may be provided with a belt tensioning means which may alter, affect, or correct the tension of said drive pulley. As mentioned above, drive belts may normally loose some of their tension soon after their first use. Thus in order to compensate for such loss, a tensioning means may be included as part of the rotatable saw apparatus. The tensioning means may comprised an adjustable platform, onto which the motor may be anchored. The adjustable platform may me provided with hinges, for example along an edge of the platform disposed furthest from the saw. The adjustable platform may additional be provided 2 0 with adjustable screws, for example, along an edge of the platform nearest the saw. The adjustable screws may be rotated in their sockets, causing the adjustable platform to rise and rotate about its hinges, in a manner that the motor is rotated further away from the saw. This rotation of the motor causes the distance from the motor to the saw to be increased, therefore allowing the compensation of the decrease in tension in the drive belt. The tension adjusting mechanism may be operated during 2 5 the operation of the rotatable saw apparatus, or when the rotatable saw apparatus is idle. It is understood that any other similar means of tensioning may be incorporated in the present rotational saw apparatus.
In accordance with a further embodiment of the present invention, there may provided for a rotatable saw apparatus wherein two or more arm members may be connected to the same motor, for example, if a motor is provided with two output shafts. Further, in accordance with another aspect, the rotatable saw apparatus may be right handed, or left handed, i.e. may have a saw on the right hand side, or the left hand side.
In accordance with a further embodiment, the rotatable saw apparatus of the present invention may be disposed on rails, in order to allow the displacement thereof.
to BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic side elevation view of a rotatable saw apparatus in accordance with the present invention;
Figure 2 is a schematic side elevation view of the rotatable saw apparatus of Figure 1 showing the saw having been displaced from a first position to a second position;
Figure 3 is a schematic top plan view of the rotatable saw apparatus of Figure 1;
Figure 4 is a sectional view along view lines A-A of Figure 3;
Figure S is a longitudinal section of the arm member of an alternative configuration of the rotatable 2 0 saw apparatus of Figure 1;
Figure 6 is a top plan view of the rotatable saw apparatus of Figure 1 showing an alternative configuration of the intermediate pulley;
Figure 7 is a top plan view of an alternative embodiment of the rotatable saw apparatus of Figure 1;
2 5 Figure 8 is a side elevation view of the rotatable saw apparatus showing the attachment of the motor to the machine frame;
Figure 9 is a side elevation view of the rotatable saw apparatus showing the motor having been displaced;
Figure 10 is an alternative configuration of rotatable saw apparatus of Figure 1, shown to be disposed on rails for displacement.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring primarily to figures 1 and 2 of the Figures0, the illustrated rotatable saw apparatus is generally designated by reference number 1. The rotatable saw apparatus generally comprises a saw 3 which is rotationally mounted on arm member 9, which arm member 9 is supported on machine frame 7. Electric motor S is anchored to machine frame 7 through base plate 27, bolt 33 and adjustable screw 35. The rotatable saw apparatus 1, namely the machine frame 7 is configured and disposed such that it may be supported on a floor, i.e. such as the shop floor of a lumber mill. It is understood however, that machine frame 7 may be configured so as to be supported on a wall or further, may be ceiling mounted.
Rotatable saw apparatus 1 comprises three (3) pulleys, namely driven pulley 11, drive pulley 1 S, and intermediate pulley 13, which intermediate pulley 13 is shown to be disposed intermediate the drive pulley 15 and driven pulley 11. Drive pulley 11 is shown disposed at first opposed end 10 of arm member 9 and is rotatably connected to saw 3 by a common shaft. Therefore the rotation of 2 0 driven pulley 11 will rotationally drive saw 3, for example in the direction of motion arrow 31.
Intermediate pulley 13 is shown disposed adjacent second opposed end 8 of arm member 9, and as further illustrated in Figure 3, has its axis of rotation 16 coaxially aligned with the axis of rotation 16 of arm member 9. Drive pulley 15 is rotationally connected to electric motor 5, and as may be seen, both electric motor 5 and drive pulley 15 are disposed such that they are not supported by arm 2 5 member 9 but rather, are supported directly by machine frame 7. It is understood however, that electric motor 5 may be supported otherwise than by machine frame 7, i.e. for example on a different or separate machine frame (not shown).
Rotatable saw apparatus 1 further comprises a displacement mechanism, comprising pneumatic piston 19, moving shaft 23, and connecting arm 21. Connecting arm 21 is shown pivotally connected to second opposed end 8 of arm member 9. Pneumatic piston 19 is connected to machine frame 7 through hinge 25, and is configured and disposed such that moving shaft 23 and connecting arm 21 are reciprocably displaceable up and down in the general direction of motion arrows 41 and 42. Therefore, when connecting arm is displaced downwardly in the direction of motion arrow 42 by the action of the pneumatic piston 19, second opposed end 8 of arm member 9 is forced downwardly, also in the general direction of motion arrow 42, causing the rotation of arm member 9 about its pivot axis 16, such that first opposed end 10 of arm member 9 is displaced upwardly in the direction of motion arrow 43. Once the displacement of connecting arm 21 in the direction of motion arrow 42 has been completed, the displacement mechanism, namely the pneumatic piston 19 reverses direction, causing the connecting arm 21 to be displaced in the direction of motion arrow 41, causing the rotation of arm member 9 about its pivot axis 16, such that first opposed end 10 of arm member 9 is displaced downwardly in the direction of motion arrow 45.
Rotatable saw apparatus 1 is further shown in the figure 1 as comprising drive belt 17, which drive belt 17 is shown simultaneously driving the three (3) pulleys, namely drive pulley 15, intermediate pulley 13 and driven pulley 11. As may be seen, electric motor 5, which is rotatably connected to drive pulley 15, may rotationally drive (i.e. rotate) pulley 15 in the direction motion arrow 37. Drive pulley 15 comprises grooves adapted to receive drive belts therein, and may, for example, be a V
2 o belt pulley. The rotation of drive pulley 15 is such that drive belt 17 is made to be displaced in the direction of motion arrow 39. The upper flight (i.e. first flight side) of drive belt 17 then passes over intermediate pulley 13, coming into contact with top surface 14 thereof, and being redirected towards driven pulley 11. Drive belt 17 then reaches driven pulley 11, and wraps around and rotationally drives driven pulley 11. Drive belt 17 then comes back toward the drive pulley 15 and 2 5 on its lower flight (i.e. second opposed flight side), comes into contact with lower surface 12 of intermediate pulley 13. Drive belt 17 then complete the loop by wrapping around drive pulley 15.
Therefore, one drive belt 17 simultaneously, drivingly, operationally connects each of the drive pulley 15, the intermediate pulley 13 and the driven pulley 11.
Figure 1 shows arm member 9, and consequently saw 3 being disposed in a first (i.e. lower) position.
The disposition of the saw 3 when in the first position is a function of the length of the arm member 9, the location of the pivot axis 16, and the displacement of the connecting arm 21 of the displacement mechanism. In addition, the diameter of the saw 3 may play a role in how low first position is, i.e. a larger diameter saw will naturally reach further down than a smaller diameter saw.
As may further be seen in Figure 1, log 2 is intended to be cut by saw 3. To do so, log 2 may be displaced in the direction of motion arrow 4 through an advancing mechanism (part of which is shown as reference number 6) in order that log 2 may be cut by saw 3.
Figure 2 is a schematic side elevation view of the rotatable saw apparatus of Figure 1 showing the saw having been displaced from a first position to a second position. Saw 3 has therefore been displaced upwardly in the direction of motion arrow 43 in relation to its position shown in Figure 1. The displacement of saw 3 between its position shown in Figure 1 and Figure 2 is shown approximately by reference number 47. As may be seen, pneumatic piston 19 has displaced the connecting arm 21 in the direction of motion arrow 42, causing the rotational displacement of arm member 9 about its axis of rotation 16, such that first opposed end 10, and consequently saw 3, were rotationally displaced in the direction of motion arrow 43.
2 0 As may be seen from Figure 2, the arm member 9 and the intermediate pulley 14 are configured and disposed in view of the displacement 47, such that when saw 3 is displaced to a second position, drive belt 17 is still in contact with intermediate pulley 13. Namely, the top flight (i.e. first flight side) of drive belt 17 is in contact with top surface 14 of intermediate pulley 13, and the bottom flight (i.e. second opposed flight side) of drive belt 17 is in contact with bottom surface 12 of 2 5 intermediate pulley 13. In accordance with an alternative configuration of the rotatable saw apparatus, for example if arm member 9 is longer or shorter than shown in Figures 1 and 2, or if displacement 47 of saw 3 is to be greater or smaller than shown, the diameter of intermediate pulley 13 may be increased or decreased, in order that drive belt 17 be always in contact at two points on the intermediate pulley 13, namely, at top surface 14 and bottom surface 12 thereof. However, in any event, the axis of rotation 16 of intermediate pulley 13 and of saw arm 9 are to be co-axially aligned.
As may be seen, log 2 has been displaced in the direction of motion arrow 4 from its position shown in Figure 1. When saw 3 is next displaced to its first position, i.e. when it is rotated downwardly about its axis 16 in the direction of motion arrow 45, the saw may effect the cutting of log 2.
As may be seen, displacement mechanism, namely pneumatic piston 19 is shown connected to machine frame 7 trough hinge 25. The hinge connection may therefore allow for a hinged, lateral displacement of the pneumatic piston 19 to allow for the fact that second opposed end 8 of arm member 9 is rotationally displaced about axis 16, and therefore its position with respect to a vertical line changes as it rotates.
Intermediate pulley 13 is configured and disposed such that it is rotatable about the axis denoted by reference 16. Intermediate pulley 13 is free turning about axis 16. Arm member 9 is also rotationally (i.e. pivotable) rotatable about the same axis 16 as intermediate pulley 13.
Figure 3 is a schematic top plan view of the rotatable saw apparatus of Figure 1. Rotatable saw apparatus 1 comprises arm member 9, which arm member 9 is shown as being made up of two 2 o spaced apart steel plate, 9a and 9b. Arm member 9 is rotationally mounted on shaft 63, which shaft 63 is fixedly connected to machine frame 7. Arm member 9 is shown being fitted with friction reducing means 69, i:e. bearings 69, which allow for the rotation of the arm member 9 about rotational axis 16. As may be understood however, the connection of arm member 9 to shaft 63 may be effected in any other known manner, so as to allow for the rotational displacement about 2 5 rotational axis 16.
As may further be seen, intermediate pulley is shown to be rotatably mounted on shaft 63, the same shaft that arm member 9 is rotatably mounted on, and therefore, their respective axis of rotation 16 are coaxially aligned. Intermediate pulley 13 is shown as being fitted with friction reducing means, i.e. bearings 71, which allow intermediate pulley to rotate freely about shaft 63. Figure 3 further depicts driven pulley 11, which is shown to be fixedly connected to shaft 61.
Saw 3 is also shown to be fixedly connected to shaft 61 through the use of locking nut 73.
Further, shaft 61 is shown being rotatably mounted to arm member 9 through the use of friction reducing means, i.e. bearings 67. Thus, the rotation of driven pulley 11 (i.e. by drive belt 17) will cause the rotation of saw 3.
Drive pulley 15 is shown to be fixedly connected to output shaft 65 of electric motor 5.
Drive pulley 15; intermediate pulley 13, and driven pulley 11 are each drivingly connected by drive belt 17. As may be seen, drive belt 17 consists of a single drive belt which simultaneously loops around each of drive pulley 15, intermediate pulley 13 and driven pulley 11.
Thus, when drive pulley 15 is rotated by and imparted with (kinetic) energy from electric motor 5, drive belt 17 is displaced in the direction of motion arrow 39, and passes over and is in contact with intermediate pulley 13. Finally, drive belt 17 causes the rotation of driven pulley 11, which in turn causes the rotation of saw 3. As further seen from Figure 3, an additional drive belt 18 is disposed adjacent drive belt 17, which second drive belt 18 also simultaneously drivingly connects drive pulley 15, intermediate pulley 13 and driven pulley 11. Each of drive pulley 15, intermediate pulley 13, and driven pulley 11 comprises additional belt grooves 75 which would allow for the use of additional drive belts (not shown).
2 0 Pneumatic piston 19 is shown as been connected to second opposed end 8 of arm member 9.
Figure 4 is a sectional view along view lines A-A of Figure 3. Figure 4 shows a side elevation view of the rotatable saw apparatus 1 without the intermediate pulley 13 shown in Figures 1 through 3.
Arm member 9 is shown rotationally mounted to shaft 63, which shaft 63 is fixedly connected to 2 5 frame 7 (as shown in Figure 3). Arm member 9 is rotatable (i.e. pivotable) about axis 16, which axis is disposed adjacent second opposed end 8. Although not shown, axis 16 is the same axis 16 about which intermediate pulley 13 rotates. Arm member 9 is rotatable about shaft 63 through the use of bearings, for example ring bearing 69.
Figure S is a longitudinal section of the arm member of an alternative embodiment of the rotatable saw apparatus. As shown, Figure 5 depicts a left hand saw, i.e. a saw 3 which is disposed on the left hand side of arm member 9, as opposed to Figures 1 to 4 which show a right hand disposed saw.
Arm member 9 is shown comprising a sleeve 80, i.e. having been welded to sleeve 80, which sleeve 80 is disposed over shaft 63. Between shaft 63 and sleeve 80 there is disposed a friction reducing means 84, such as a bushing or bearing. Arm member 9, an sleeve 80 are shown to be affixed to machine frame 7 through tapered mounts 85, such as self cinching tapered mounts. Saw 3 is shown to be affixed to shaft 61, and driven pulley 11 is also affixed to shaft 61.
Shaft 61 is rotatably mounted to arm member 9 through the bearings 81.
Figure 6 is a top plan view of the rotatable saw apparatus showing an alternative configuration of the intermediate pulley 13. In accordance with this configuration, intermediate pulley 13 is rotatably mounted to shaft 82. Arm member 9 is rotatably mounted to shaft 63, and both shaft 63 and shaft 81 are coaxially aligned such that intermediate pulley 13 and arm member 9 are each rotatable about axis 16. Shaft 82 is fixedly connected to support 80, which support 80 may form part of machine frame 7, or may be a separate structure.
Figure 7 is a top plan view of an alternative embodiment of the rotatable saw apparatus of Figure 1. Figure 6 shows a dual rotatable saw apparatus 99, wherein one electric motor 109 having two 2 0 output shafts 117 and 118 drives two separate rotatable saw apparatus, namely arm member 112 and 113. As may be seen, the two rotatable saw apparatus are similar to each other, each respectively comprising a saw 100, 1 O 1 connected to a driven pulley 102,103 which driven pulley is driven from a drive pulley 106, 107 by a drive belt 116, 115. Each rotatable saw apparatus comprises an intermediate pulley, respectively 104 and 105 and each saw arm 112 and 113 comprises apneumatic 2 5 piston 120 and 121. Each arm member 112, 113 is rotatably mounted onto a shaft 110,111, affixed to the machine frame 108.
Referring to Figures 8 and 9, there is shown a side elevation view of the rotatable saw apparatus 1 showing the attachment of the motor 5 to the machine frame 7. Motor 5 is shown fixedly attached to support plate 27, which support plate 27 is hingedly connected by hinge 29 to base 28. As may be seen in figure 9, positioning screw 35 is configured and disposed such that it may lower or raise support plate 27, which in turn causes the rotational displacement of the support plate 27 and motor in the direction of motion arrow 36, thus displacing motor 5, and drive pulley 15 further away 5 from driven pulley 11 (as shown in figures 1 to 4). As may be understood, as motor 5 and drive pulley 15 are displaced further away driven pulley 11, the tension in drive belt 17 may be increased.
As may be understood, this rotation of motor 5 in the direction of motion arrow 36 may be accomplished while the rotatable saw apparatus is not in operation, or alternatively, while the saw is idle. As explained above, the tension in a drive belt may decrease after a short period of operation, and the tensioning means may counter such loss. As may also be understood, any other type of initial tensioning means may be used instead of the one shown.
Figure 10 is an alternative configuration of rotatable saw apparatus 1 of Figure 1, shown to be disposed on rails for displacement. Frame 7 is shown to be fitted with slots 152 and 162, which slots are configured and disposed to accept therein rails 151 and 161. Rails 151 and 161 are shown to be affixed to supports 150 and 160. The slots 161 and 162 are slidingly engage in rails 151 and 161 respectively, which allows rotatable saw apparatus 1 to be displaced along an axis perpendicular to the page.
BACKGROUND OF THE INVENTION
The present invention relates to the field of industrial saws and more particularly to the field of saws having an articulated, pivotable or rotatable arm, such as swing saws, which may be used in saw mills for cutting logs and other lumber.
Swing saws for use in the lumber industry are known, for example US Patent no.5,094,654 to Strom.
However known swing saws are characterised by certain limitation and disadvantages. For example, known swing saws, are very heavy, which can severely limits the displacement speed of the their rotatable arm, and therefore, their speed of operation. Alternatively, known swing saws may require a very powerful motor to effect the displacement of their rotatable arm in order to compensated for their excessive weight. The excessive mass of the rotatable arm of known swing saws may be due to a number of reasons, such as for example, their long or excessive length, or the weight of the heavy mechanical components of their drive mechanisms. Further, rotatable saw arms known in the prior also have the motor driving the saw mounted or installed directly on the rotatable arm itself, thus needlessly adding a very large mass which must be displaced with each movement of the saw arm.
Prior attempts at overcoming said problems resulted in unsatisfactory results.
For example, moving the motor off the rotatable arm caused the tension of their drive mechanisms, such as a drive belt, to vary through the movement of the rotatable arm. This was due to the fact that the radius of curvature of the rotatable arm was different than the radius of curvature of the drive belt. The unwanted variation in the tension of the belt drive mechanisms was undesirable from an operational view point, because it caused temporary loss of power to the saw, and unwanted variations in the power available to the saw, i.e. there were peaks and valleys in the power output.. Further, the S variation in the tension in the drive belt caused premature wear of the drive belt.
Known swing arms are also configured such that they are pivotably displaced about one of their extremities, thus requiring a large force, and therefore a large motor to effect the displacement thereof.
The low operational speed and efficiency of known swing saws, the undesirable variation in the tension in the drive belt, and the requirement for large motors make known saws inefficient to operate, more expensive to build, and therefore they do not meet with commercial success.
Therefore, it would be advantageous to provide a rotatable saw apparatus wherein the saw is driven by a constant tension driving means, wherein the tension in the drive belt does not vary as the saw arm is rotated about its axis of rotation.
It would be further advantageous to provide a rotatable saw apparatus wherein the motor is not disposed on the saw arm itself.
It would be further advantageous to provide a rotatable saw apparatus having a very high speed of operation.
It would be further advantageous to provide a rotatable saw apparatus wherein the saw is driven from the drive motor through a continuous drive belt, wherein the pivoting of the arm of the rotatable saw apparatus does not cause a lengthening or shortening of said belt drive means, therefore keeping the tension of said drive belt constant.
It would be further advantageous to provide a rotatable saw apparatus wherein the rotational displacement of the arm is effected by a pneumatic piston.
It would be further advantageous to provide a rotatable saw apparatus wherein the saw arm is configured and disposed such that its axis of rotation acts as a fulcrum and takes advantage of the lever effect, thus requiring a reduced force to rotationally displace the saw arm.
SUIVFVIARY OF THE INVENTION
The present invention, in accordance with one aspect provides for a rotatable saw apparatus comprising a machine frame, an arm member, said arm member being pivotably mounted on said machine frame such that said arm member is pivotable about a pivot axis a circular saw rotatably mounted on said arm member a displacement mechanism a drive belt means a pulley drive component for inducing rotation of said saw comprising a driven pulley means, a drive pulley means and an intermediate pulley means, said driven pulley means being rotatably mounted on said arm member and connected to said saw for the rotation thereof, said drive pulley means being drivingly connected to a motor, said drive pulley means being disposed at a location spaced apart. from said arm member, said intermediate pulley means being disposed 2 0 intermediate said drive pulley means and said driven pulley means, said displacement mechanism being connected to said arm member such that said displacement mechanism is able to pivotally displace: said arm member about said pivot axis of said arm member such that said saw is displaceable between a first position and a second position, said drive belt means having a first end and a second end, said first end engaging said drive pulley 2 5 means, said second end engaging said driven pulley means, said drive belt means defining a first flight side and an opposed second flight side, said first and second flight sides each being connected respectively to said first and second ends, said drive belt means simultaneously engaging said drive pulley means, said intermediate pulley means and said driven pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second positions, said intermediate pulley means having a diameter larger than the diameter of the drive pulley means and of the driven pulley means.
In accordance with another aspect the present invention provides a rotatable saw apparatus comprising a machine frame, an arm member, said arm member being pivotably mounted on said machine frame such that said arm member is pivotable about a pivot axis a circular saw rotatably mounted on said arm member a driven pulley means rotatably mounted on said arm member and connected to said saw for the rotation thereof a drive pulley means drivingly connected to a motor, said drive pulley being disposed at a location spaced apart from said arm member, an intermediate pulley means disposed intermediate said drive pulley means and said driven pulley means, said intermediate pulley means being configured and disposed such that its axis of rotation is co-axially aligned with said pivot axis of said arm member a displacement mechanism and a drive belt means said displacement mechanism being connected to said arm member such that said displacement 2 0 mechanism is able to pivotally displace said arm member about said pivot axis of said arm member such that said saw is displaceable between a first position and a second position, said drive belt means having a first end and a second end, said first end engaging said drive pulley means, said second end engaging said driven pulley means, said drive belt means defining a first flight side and an opposed second flight side, said first and second flight sides each being connected 2 5 respectively to said first and second ends, said drive belt means simultaneously engaging said drive pulley means, said intermediate pulley means and said driven pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second positions, said arm member having opposed first and second arm ends, said pivot axis being disposed between said first and second arm ends so as to divide the arm member into a first side terminating in said S
first arm end and a second side terminating in said second arm end, said saw being mounted to said first side of the arm member and said dlisplacement mechanism being connected to said second side of the arm member.
In accordance with the present invention a rotatable saw apparatus may comprise an arm member having a saw rotationally mounted thereon, which saw may so be driven by a drive belt means so as to facilitate a constant tension thereof. The arm member is to be chosen so as to be of sufficiently sturdy construction so as to be able to withstand the rigours of an industrial application, such as for example, a saw mill. The arm member may be configured in any known manner, and __ _.
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-_.__.____.____________ Sa may for example comprise a hollow steel member of, for example, round or square shape, or may comprise spaced apart steel plates, connected together by intermediate spacer(s). In accordance with a particular embodiment, the arm member may be configured so as meet operational parameters, for example, such as deflection, serviceability, etc... yet be as light as possible in order to allow for the high operational speeds required, i.e. the high speed of displacement of the arm member, that is desired to be achieved.
The arm member may have a generally elongated configuration comprising a longitudinal axis, and may further comprise opposed first and second ends. The saw member may have a saw rotatably mounted adjacent the first opposed end, and said saw may be configured and disposed to cut logs, lumber, etc... The logs or lumber to be cut may be advanced or placed into position for cutting adjacent the saw through a feeding system. The saw may be any type of industrial saw suitable for lumber mill or saw mill operation, for example, a circular saw. Different diameter saws may be mounted on the arm member, depending on the application or operating conditions. It is understood that the saw may be suitable for clockwise or counter clockwise operation.
The arm member may pivotably (i.e. be rotatably) connected (i.e. hinged, pinned, pivoted, etc...) such that it may pivot about a pivot axis. In accordance with a general aspect, the pivot axis may be at right angle to the longitudinal axis of the arm member. The location of the axis about which the 2 0 arm member may be pivoted may be such so as to minimize the forces required to rotate said arm member (and saw), and therefore reduce the horsepower of the motor required to operate the displacement of the arm member. Alternatively, the location of the pivot axis may be such so as to increase the speed and operational efficiency of the rotatable saw apparatus.
As may be understood, the rotatable saw apparatus of the present invention may be configured and disposed to achieve high 2 5 operational velocities, i.e. wherein the velocity of the rotational displacement of the arm member is to be maximized. Thus, the length of he arm member may be minimized as much as possible in order to reduce the mass thereof to be displaced. Further, the arm member may be pivoted about a pivot axis disposed such as to maximize the lever effect of the arm member on the saw. The pivot axis, i.e. the point about which the arm member is rotated, may act as a fulcrum, in order to maximize the effect of the applied force necessary to rotate the arm member.
Therefore, in accordance with one aspect, the pivot axis of the arm member may be adjacent its second opposed end, and the force necessary to cause the rotation of the arm member may be applied between the second opposed end of the arm member and the pivot axis. In accordance with the present invention, the pivot axis of the arm member may be spaced apart from the second opposed end of the arm member. In accordance with the present invention, the pivot axis of rotation may be disposed adjacent the middle point of the arm member, and the force necessary to cause the rotation of the arm member may be applied at or near the second opposed end of the arm member.
In accordance with yet a further embodiment, the force necessary to cause the rotation of the arm member may be applied at a point intermediate the pivot axis and the first opposed end of the arm member.
It is understood that the saw member is to be supported on (i.e. rotatably mounted or connected to) a machine frame (i.e. or structure) which machine frame may form part of the rotatable saw apparatus as a whole, or may be a stand-alone structure. As may be understood, the frame may be constructed in accordance with known industrial machinery practices, and may comprise the necessary controls, wiring, switches, bearings, bushings, and other components necessary for its intended operation.
As mentioned above, the arm member may be rotationally connected to a machine frame such that 2 0 it may be rotatable about a rotational axis. The rotational connection of the arm member may be such that the first opposed end of the saw arm, and the saw rotationally mounted at or adj acent said opposed first end, may be rotatably displaceable from a first (i.e. lower) position, to a second (i.e.
higher) position. The rotational displacement of the first opposed end and of the saw may be in the (approximate) shape of an arc of a circle. As may be understood, the rotational displacement of the 2 5 saw may be effected such that, for example, when being displaced towards the first (i.e. lower) position, the (rotating) saw may be brought into contact with a piece of lumber to be cut. The rotational displacement from the first to the second position may be reversed, and the reciprocating cycle may be repeated any number of times. It is understood that the displacement of the saw in one or both directions (i.e. the distance travelled) may be varied in accordance with operational conditions, or in accordance with the particular piece of lumber to be cut.
The rotatable saw apparatus may further comprise a displacement mechanism configured and disposed so as to apply a reciprocal force to the arm member so as to effect the displacement of the arm member about its pivot axis, as explained above. The displacement mechanism may comprise a number of components, including a pneumatic piston to power the displacement mechanism. It is understood that any other type of force generating means, such as an electric motor, hydraulic piston, etc... may be used to power the displacement mechanism. The displacement mechanism may comprise a force transfer member operationally connected to the pneumatic piston, which is hingedly connected to the arm member. Therefore, the force transfer member may, for example, be hingedly connected to the arm member between the pivot axis and the second opposed end, or even at the second opposed end. The pneumatic piston or cylinder may therefore impart, through the force transfer member, a force in one direction, (for example, downwardly) at or near the second opposed end of the arm member, causing the first opposed end to be rotated upwardly, i.e. towards its second position. Following this, the pneumatic piston may impart, again through the force transfer member, a force in another direction, i.e. for example, upwardly at or near the second opposed end, causing the first opposed end of the arm member to be rotated downwardly, i.e. towards its first position.
This reciprocal, up and down cycle may be repeated any number of times. For example, the pneumatic cylinder may cause the arm member to effect 240 cycles per minute, through a 2 0 displacement of 5 inches, (i.e. a 5 inch displacement in one direction, followed by a 5 inch displacement in another direction).
In accordance with the present invention, there is provided for a driven pulley which may be rotatably mounted to the arm member, and which may be disposed at or near the first opposed end 2 5 thereof. Said driven pulley may be rotatably connected to said saw through direct means, i.e. for example, the driven pulley and the saw may each be affixed to a (common) shaft, which common shaft may be supported by the arm member through friction reducing means, i.e.
such as bearings, bushings, etc.... Alternatively, the driven pulley may be rotatably connected to the saw through indirect means, i.e. through gears, etc..., in which case each of the driven pulley and the saw may be mounted to the arm member through appropriate connections, and each may be provided with appropriate anti friction means.
The present invention, further comprises a drive pulley which may be operationally connected to a motor means, such as for example, an electric motor. It is to be understood that the drive pulley is not to be supported on the arm member, but is to be disposed at a location spaced apart from the saw member, i.e. for example, it is to be supported opposite the second opposed end of the arm member. In accordance with a particular embodiment, the respective axis of rotation of the drive pulley and of the driven pulley may be disposed so as to be parallel to each other. Further the drive pulley and the driven pulley may be oriented in relation to the arm member such that each of the drive pulley and the driven pulley may rotate in a common plane. The drive pulley may be supported by the machine frame of the rotatable saw apparatus, or alternatively, may be supported otherwise, but in any event, not by the arm member. As may be understood, the drive pulley may comprised necessary friction reducing means, i.e. bearings, and other components, to effect its intended purpose.
As mentioned above, the drive pulley may be operationally connected to a motor means, such as for example, an electric motor, hydraulic motor, internal combustion engine, etc... The motor is to be disposed such that it is not supported on the arm member, but is instead supported (attached, 2 0 anchored, etc) at a location spaced apart from the arm member. For example, the motor may be supported by the machine frame of the rotatable saw apparatus, or alternatively, the motor may be supported by another structure. In any event, the motor is not to be supported onto or by the arm member. As may be understood, the motor may comprise the necessary controls, switches, etc... to effect its intended purpose. In accordance with a particular embodiment, the motor may comprise 2 5 an electric motor, of for example 3 to 15 horsepower, which motor may be anchored to the frame of the rotatable saw apparatus. The motor may be configured and disposed such that its power output shaft may be the shaft onto which the drive pulley is directly affixed. In this configuration, the motor may be anchored to the machine frame, and disposed so as to behind the arm member, i.e. adj acent the second opposed end, but remote from the first opposed end, with its output shaft disposed parallel to the axis of rotation of the driven pulley. Further, the configuration of the motor is to be such that its power output shaft be disposed such that the drive pulley affixed thereon may rotate in the same plane as the driven pulley. Alternatively, the power output shaft of the motor, and the shaft of the drive pulley may be indirectly connected through gears, a gear box, etc...
In addition to the drive pulley and the driven pulley, the present invention further provides for an intermediate pulley. The intermediate pulley may be disposed intermediate said drive pulley and said driven pulley, wherein the axis of rotation of each of the three pulleys may be parallel to each other, and such that each of the drive pulley, the driven pulley and the intermediate pulley may rotate in a common plane. As may be understood, the configuration and disposition of the drive pulley, the intermediate pulley and of the driven pulley is to be such that all three pulleys may be driven by one single driving belt mechanism, i.e. such as for example, a drive belt, chain, etc....
Thus, a single drive belt may simultaneously, drivingly connect the three pulleys. The drive belt may therefore be imparted with rotational force by the drive pulley, and be made to rotate, such that the upper flight of the drive belt may touch and pass over the upper edge of the intermediate pulley, continue towards the driven pulley, impart the driven pulley with rotational force, and then return towards the drive pulley, with its lower flight touching and passing under the intermediate pulley.
It is understood that the drive pulley, the intermediate pulley, and the driven pulley may be driven 2 o by more than one drive belt, for example two or more drive belts. In this configuration, each of hte individual drive belts may drive each of the three pulleys, and the two or more drive belts may be disposed besides one another, i.e. adj acent each other. In this configuration, each of the drive pulley, the driven pulley and the intermediate pulley may comprise a plurality of parallel grooves, each of which may be adapted to accept therein a drive belt. In an alternative configuration, the drive belts) 2 5 may be replaced by chain(s), in which case the pulleys may also comprise sprockets to engage with the chain(s), i.e. the drive means may comprise chain(s).
The intermediate pulley may be configured and disposed such that the axis of rotation of said intermediate pulley may be coaxially aligned with the axis of rotational of the arm member. Thus, as may be understood, the intermediate pulley may be rotational mounted on a shaft which is supported on a stand-alone support, or which shaft may be supported by the machine frame itself.
The intermediate pulley may alternatively be supported by the arm member itself, namely, that a shaft may be mounted on the arm member, and onto which shaft the intermediate pulley is rotationally mounted. In accordance with yet another particular embodiment, the intermediate pulley and the arm member may each be rotationally mounted on a common shaft, which shaft may be supported by the machine frame. As may be understood, in accordance with this particular embodiment, as the intermediate pulley and the arm member are each rotationally mounted on the same shaft, their respective axis of rotation will necessarily be co-axially aligned. It is understood that co-axially aligned may not mean exactly co-axially aligned, but may allow for some variation from a perfect co-alignment.
It is understood that in accordance with this configuration, (i.e. wherein the pivot axis of the intermediate pulley is coaxially aligned with the pivot axis of the arm member), the displacement of the saw from a first to a second position defines a first sector (i.e. a sector is defined as the geometric figure bounded by two equal radii and the included arc of a circle, which equal radii meet at the apex). Further, the displacement of the driven pulley from a first to a second position defines a second sector. It is to be understood that the first sector and the second sector may have the same apex, i.e their respective apex overlap. Therefore, there may be no relative displacement (axially or 2 o otherwise) between the saw and the driven pulley as they are displaced from a first to a second position, and therefore there may be no increase or decrease in the distance that the drive belt has to travel. Consequently, there may be no corresponding increase or decrease in the tension in the belt. Thus as may be understood, the geometry, i.e. the disposition of the components of the rotatable saw apparatus may be such that the rotational displacement of the saw from a first to a 2 5 second position may not cause a change in the tension of the drive belt.
It is to be understood, however, that the tension in the drive belt may by subject to some (minor) variations caused by operational loading thereon, i.e. when the saw is brought into contact with the log, the increased resistance brought to bear on the saw may cause some change in the tension of the drive belt. Further, a new drive belt may normally loose some of its tension soon after it is first put into operation.
In accordance with the present invention, the intermediate pulley may be sized such that the drive belt means (e.g. belt, or chain, etc...) which connects the drive pulley, the intermediate pulley and the driven pulley may always be in contact with the upper and lower surfaces of the intermediate pulley. Thus in accordance with this embodiment, the intermediate pulley may be oversized, i.e.
may be of a large diameter, for example, of a larger diameter than either the drive pulley or the driven pulley. The size of the diameter of the intermediate pulley may be combination of a number of factors, such as the vertical travel of the saw, the length of the arm member, the disposition of the drive pulley, etc...
In accordance with a further embodiment of the present invention, there may be provided with a belt tensioning means which may alter, affect, or correct the tension of said drive pulley. As mentioned above, drive belts may normally loose some of their tension soon after their first use. Thus in order to compensate for such loss, a tensioning means may be included as part of the rotatable saw apparatus. The tensioning means may comprised an adjustable platform, onto which the motor may be anchored. The adjustable platform may me provided with hinges, for example along an edge of the platform disposed furthest from the saw. The adjustable platform may additional be provided 2 0 with adjustable screws, for example, along an edge of the platform nearest the saw. The adjustable screws may be rotated in their sockets, causing the adjustable platform to rise and rotate about its hinges, in a manner that the motor is rotated further away from the saw. This rotation of the motor causes the distance from the motor to the saw to be increased, therefore allowing the compensation of the decrease in tension in the drive belt. The tension adjusting mechanism may be operated during 2 5 the operation of the rotatable saw apparatus, or when the rotatable saw apparatus is idle. It is understood that any other similar means of tensioning may be incorporated in the present rotational saw apparatus.
In accordance with a further embodiment of the present invention, there may provided for a rotatable saw apparatus wherein two or more arm members may be connected to the same motor, for example, if a motor is provided with two output shafts. Further, in accordance with another aspect, the rotatable saw apparatus may be right handed, or left handed, i.e. may have a saw on the right hand side, or the left hand side.
In accordance with a further embodiment, the rotatable saw apparatus of the present invention may be disposed on rails, in order to allow the displacement thereof.
to BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic side elevation view of a rotatable saw apparatus in accordance with the present invention;
Figure 2 is a schematic side elevation view of the rotatable saw apparatus of Figure 1 showing the saw having been displaced from a first position to a second position;
Figure 3 is a schematic top plan view of the rotatable saw apparatus of Figure 1;
Figure 4 is a sectional view along view lines A-A of Figure 3;
Figure S is a longitudinal section of the arm member of an alternative configuration of the rotatable 2 0 saw apparatus of Figure 1;
Figure 6 is a top plan view of the rotatable saw apparatus of Figure 1 showing an alternative configuration of the intermediate pulley;
Figure 7 is a top plan view of an alternative embodiment of the rotatable saw apparatus of Figure 1;
2 5 Figure 8 is a side elevation view of the rotatable saw apparatus showing the attachment of the motor to the machine frame;
Figure 9 is a side elevation view of the rotatable saw apparatus showing the motor having been displaced;
Figure 10 is an alternative configuration of rotatable saw apparatus of Figure 1, shown to be disposed on rails for displacement.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring primarily to figures 1 and 2 of the Figures0, the illustrated rotatable saw apparatus is generally designated by reference number 1. The rotatable saw apparatus generally comprises a saw 3 which is rotationally mounted on arm member 9, which arm member 9 is supported on machine frame 7. Electric motor S is anchored to machine frame 7 through base plate 27, bolt 33 and adjustable screw 35. The rotatable saw apparatus 1, namely the machine frame 7 is configured and disposed such that it may be supported on a floor, i.e. such as the shop floor of a lumber mill. It is understood however, that machine frame 7 may be configured so as to be supported on a wall or further, may be ceiling mounted.
Rotatable saw apparatus 1 comprises three (3) pulleys, namely driven pulley 11, drive pulley 1 S, and intermediate pulley 13, which intermediate pulley 13 is shown to be disposed intermediate the drive pulley 15 and driven pulley 11. Drive pulley 11 is shown disposed at first opposed end 10 of arm member 9 and is rotatably connected to saw 3 by a common shaft. Therefore the rotation of 2 0 driven pulley 11 will rotationally drive saw 3, for example in the direction of motion arrow 31.
Intermediate pulley 13 is shown disposed adjacent second opposed end 8 of arm member 9, and as further illustrated in Figure 3, has its axis of rotation 16 coaxially aligned with the axis of rotation 16 of arm member 9. Drive pulley 15 is rotationally connected to electric motor 5, and as may be seen, both electric motor 5 and drive pulley 15 are disposed such that they are not supported by arm 2 5 member 9 but rather, are supported directly by machine frame 7. It is understood however, that electric motor 5 may be supported otherwise than by machine frame 7, i.e. for example on a different or separate machine frame (not shown).
Rotatable saw apparatus 1 further comprises a displacement mechanism, comprising pneumatic piston 19, moving shaft 23, and connecting arm 21. Connecting arm 21 is shown pivotally connected to second opposed end 8 of arm member 9. Pneumatic piston 19 is connected to machine frame 7 through hinge 25, and is configured and disposed such that moving shaft 23 and connecting arm 21 are reciprocably displaceable up and down in the general direction of motion arrows 41 and 42. Therefore, when connecting arm is displaced downwardly in the direction of motion arrow 42 by the action of the pneumatic piston 19, second opposed end 8 of arm member 9 is forced downwardly, also in the general direction of motion arrow 42, causing the rotation of arm member 9 about its pivot axis 16, such that first opposed end 10 of arm member 9 is displaced upwardly in the direction of motion arrow 43. Once the displacement of connecting arm 21 in the direction of motion arrow 42 has been completed, the displacement mechanism, namely the pneumatic piston 19 reverses direction, causing the connecting arm 21 to be displaced in the direction of motion arrow 41, causing the rotation of arm member 9 about its pivot axis 16, such that first opposed end 10 of arm member 9 is displaced downwardly in the direction of motion arrow 45.
Rotatable saw apparatus 1 is further shown in the figure 1 as comprising drive belt 17, which drive belt 17 is shown simultaneously driving the three (3) pulleys, namely drive pulley 15, intermediate pulley 13 and driven pulley 11. As may be seen, electric motor 5, which is rotatably connected to drive pulley 15, may rotationally drive (i.e. rotate) pulley 15 in the direction motion arrow 37. Drive pulley 15 comprises grooves adapted to receive drive belts therein, and may, for example, be a V
2 o belt pulley. The rotation of drive pulley 15 is such that drive belt 17 is made to be displaced in the direction of motion arrow 39. The upper flight (i.e. first flight side) of drive belt 17 then passes over intermediate pulley 13, coming into contact with top surface 14 thereof, and being redirected towards driven pulley 11. Drive belt 17 then reaches driven pulley 11, and wraps around and rotationally drives driven pulley 11. Drive belt 17 then comes back toward the drive pulley 15 and 2 5 on its lower flight (i.e. second opposed flight side), comes into contact with lower surface 12 of intermediate pulley 13. Drive belt 17 then complete the loop by wrapping around drive pulley 15.
Therefore, one drive belt 17 simultaneously, drivingly, operationally connects each of the drive pulley 15, the intermediate pulley 13 and the driven pulley 11.
Figure 1 shows arm member 9, and consequently saw 3 being disposed in a first (i.e. lower) position.
The disposition of the saw 3 when in the first position is a function of the length of the arm member 9, the location of the pivot axis 16, and the displacement of the connecting arm 21 of the displacement mechanism. In addition, the diameter of the saw 3 may play a role in how low first position is, i.e. a larger diameter saw will naturally reach further down than a smaller diameter saw.
As may further be seen in Figure 1, log 2 is intended to be cut by saw 3. To do so, log 2 may be displaced in the direction of motion arrow 4 through an advancing mechanism (part of which is shown as reference number 6) in order that log 2 may be cut by saw 3.
Figure 2 is a schematic side elevation view of the rotatable saw apparatus of Figure 1 showing the saw having been displaced from a first position to a second position. Saw 3 has therefore been displaced upwardly in the direction of motion arrow 43 in relation to its position shown in Figure 1. The displacement of saw 3 between its position shown in Figure 1 and Figure 2 is shown approximately by reference number 47. As may be seen, pneumatic piston 19 has displaced the connecting arm 21 in the direction of motion arrow 42, causing the rotational displacement of arm member 9 about its axis of rotation 16, such that first opposed end 10, and consequently saw 3, were rotationally displaced in the direction of motion arrow 43.
2 0 As may be seen from Figure 2, the arm member 9 and the intermediate pulley 14 are configured and disposed in view of the displacement 47, such that when saw 3 is displaced to a second position, drive belt 17 is still in contact with intermediate pulley 13. Namely, the top flight (i.e. first flight side) of drive belt 17 is in contact with top surface 14 of intermediate pulley 13, and the bottom flight (i.e. second opposed flight side) of drive belt 17 is in contact with bottom surface 12 of 2 5 intermediate pulley 13. In accordance with an alternative configuration of the rotatable saw apparatus, for example if arm member 9 is longer or shorter than shown in Figures 1 and 2, or if displacement 47 of saw 3 is to be greater or smaller than shown, the diameter of intermediate pulley 13 may be increased or decreased, in order that drive belt 17 be always in contact at two points on the intermediate pulley 13, namely, at top surface 14 and bottom surface 12 thereof. However, in any event, the axis of rotation 16 of intermediate pulley 13 and of saw arm 9 are to be co-axially aligned.
As may be seen, log 2 has been displaced in the direction of motion arrow 4 from its position shown in Figure 1. When saw 3 is next displaced to its first position, i.e. when it is rotated downwardly about its axis 16 in the direction of motion arrow 45, the saw may effect the cutting of log 2.
As may be seen, displacement mechanism, namely pneumatic piston 19 is shown connected to machine frame 7 trough hinge 25. The hinge connection may therefore allow for a hinged, lateral displacement of the pneumatic piston 19 to allow for the fact that second opposed end 8 of arm member 9 is rotationally displaced about axis 16, and therefore its position with respect to a vertical line changes as it rotates.
Intermediate pulley 13 is configured and disposed such that it is rotatable about the axis denoted by reference 16. Intermediate pulley 13 is free turning about axis 16. Arm member 9 is also rotationally (i.e. pivotable) rotatable about the same axis 16 as intermediate pulley 13.
Figure 3 is a schematic top plan view of the rotatable saw apparatus of Figure 1. Rotatable saw apparatus 1 comprises arm member 9, which arm member 9 is shown as being made up of two 2 o spaced apart steel plate, 9a and 9b. Arm member 9 is rotationally mounted on shaft 63, which shaft 63 is fixedly connected to machine frame 7. Arm member 9 is shown being fitted with friction reducing means 69, i:e. bearings 69, which allow for the rotation of the arm member 9 about rotational axis 16. As may be understood however, the connection of arm member 9 to shaft 63 may be effected in any other known manner, so as to allow for the rotational displacement about 2 5 rotational axis 16.
As may further be seen, intermediate pulley is shown to be rotatably mounted on shaft 63, the same shaft that arm member 9 is rotatably mounted on, and therefore, their respective axis of rotation 16 are coaxially aligned. Intermediate pulley 13 is shown as being fitted with friction reducing means, i.e. bearings 71, which allow intermediate pulley to rotate freely about shaft 63. Figure 3 further depicts driven pulley 11, which is shown to be fixedly connected to shaft 61.
Saw 3 is also shown to be fixedly connected to shaft 61 through the use of locking nut 73.
Further, shaft 61 is shown being rotatably mounted to arm member 9 through the use of friction reducing means, i.e. bearings 67. Thus, the rotation of driven pulley 11 (i.e. by drive belt 17) will cause the rotation of saw 3.
Drive pulley 15 is shown to be fixedly connected to output shaft 65 of electric motor 5.
Drive pulley 15; intermediate pulley 13, and driven pulley 11 are each drivingly connected by drive belt 17. As may be seen, drive belt 17 consists of a single drive belt which simultaneously loops around each of drive pulley 15, intermediate pulley 13 and driven pulley 11.
Thus, when drive pulley 15 is rotated by and imparted with (kinetic) energy from electric motor 5, drive belt 17 is displaced in the direction of motion arrow 39, and passes over and is in contact with intermediate pulley 13. Finally, drive belt 17 causes the rotation of driven pulley 11, which in turn causes the rotation of saw 3. As further seen from Figure 3, an additional drive belt 18 is disposed adjacent drive belt 17, which second drive belt 18 also simultaneously drivingly connects drive pulley 15, intermediate pulley 13 and driven pulley 11. Each of drive pulley 15, intermediate pulley 13, and driven pulley 11 comprises additional belt grooves 75 which would allow for the use of additional drive belts (not shown).
2 0 Pneumatic piston 19 is shown as been connected to second opposed end 8 of arm member 9.
Figure 4 is a sectional view along view lines A-A of Figure 3. Figure 4 shows a side elevation view of the rotatable saw apparatus 1 without the intermediate pulley 13 shown in Figures 1 through 3.
Arm member 9 is shown rotationally mounted to shaft 63, which shaft 63 is fixedly connected to 2 5 frame 7 (as shown in Figure 3). Arm member 9 is rotatable (i.e. pivotable) about axis 16, which axis is disposed adjacent second opposed end 8. Although not shown, axis 16 is the same axis 16 about which intermediate pulley 13 rotates. Arm member 9 is rotatable about shaft 63 through the use of bearings, for example ring bearing 69.
Figure S is a longitudinal section of the arm member of an alternative embodiment of the rotatable saw apparatus. As shown, Figure 5 depicts a left hand saw, i.e. a saw 3 which is disposed on the left hand side of arm member 9, as opposed to Figures 1 to 4 which show a right hand disposed saw.
Arm member 9 is shown comprising a sleeve 80, i.e. having been welded to sleeve 80, which sleeve 80 is disposed over shaft 63. Between shaft 63 and sleeve 80 there is disposed a friction reducing means 84, such as a bushing or bearing. Arm member 9, an sleeve 80 are shown to be affixed to machine frame 7 through tapered mounts 85, such as self cinching tapered mounts. Saw 3 is shown to be affixed to shaft 61, and driven pulley 11 is also affixed to shaft 61.
Shaft 61 is rotatably mounted to arm member 9 through the bearings 81.
Figure 6 is a top plan view of the rotatable saw apparatus showing an alternative configuration of the intermediate pulley 13. In accordance with this configuration, intermediate pulley 13 is rotatably mounted to shaft 82. Arm member 9 is rotatably mounted to shaft 63, and both shaft 63 and shaft 81 are coaxially aligned such that intermediate pulley 13 and arm member 9 are each rotatable about axis 16. Shaft 82 is fixedly connected to support 80, which support 80 may form part of machine frame 7, or may be a separate structure.
Figure 7 is a top plan view of an alternative embodiment of the rotatable saw apparatus of Figure 1. Figure 6 shows a dual rotatable saw apparatus 99, wherein one electric motor 109 having two 2 0 output shafts 117 and 118 drives two separate rotatable saw apparatus, namely arm member 112 and 113. As may be seen, the two rotatable saw apparatus are similar to each other, each respectively comprising a saw 100, 1 O 1 connected to a driven pulley 102,103 which driven pulley is driven from a drive pulley 106, 107 by a drive belt 116, 115. Each rotatable saw apparatus comprises an intermediate pulley, respectively 104 and 105 and each saw arm 112 and 113 comprises apneumatic 2 5 piston 120 and 121. Each arm member 112, 113 is rotatably mounted onto a shaft 110,111, affixed to the machine frame 108.
Referring to Figures 8 and 9, there is shown a side elevation view of the rotatable saw apparatus 1 showing the attachment of the motor 5 to the machine frame 7. Motor 5 is shown fixedly attached to support plate 27, which support plate 27 is hingedly connected by hinge 29 to base 28. As may be seen in figure 9, positioning screw 35 is configured and disposed such that it may lower or raise support plate 27, which in turn causes the rotational displacement of the support plate 27 and motor in the direction of motion arrow 36, thus displacing motor 5, and drive pulley 15 further away 5 from driven pulley 11 (as shown in figures 1 to 4). As may be understood, as motor 5 and drive pulley 15 are displaced further away driven pulley 11, the tension in drive belt 17 may be increased.
As may be understood, this rotation of motor 5 in the direction of motion arrow 36 may be accomplished while the rotatable saw apparatus is not in operation, or alternatively, while the saw is idle. As explained above, the tension in a drive belt may decrease after a short period of operation, and the tensioning means may counter such loss. As may also be understood, any other type of initial tensioning means may be used instead of the one shown.
Figure 10 is an alternative configuration of rotatable saw apparatus 1 of Figure 1, shown to be disposed on rails for displacement. Frame 7 is shown to be fitted with slots 152 and 162, which slots are configured and disposed to accept therein rails 151 and 161. Rails 151 and 161 are shown to be affixed to supports 150 and 160. The slots 161 and 162 are slidingly engage in rails 151 and 161 respectively, which allows rotatable saw apparatus 1 to be displaced along an axis perpendicular to the page.
Claims (7)
1. A rotatable saw apparatus comprising a machine frame, an arm member, said arm member being pivotably mounted on said machine frame such that said arm member is pivotable about a pivot axis a circular saw rotatably mounted on said arm member a displacement mechanism a drive belt means a pulley drive component for inducing rotation of said saw comprising a driven pulley means, a drive pulley means and an intermediate pulley means, said driven pulley means being rotatably mounted on said arm member and connected to said saw for the rotation thereof, said drive pulley means being drivingly connected to a motor, said drive pulley means being disposed at a location spaced apart from said arm member, said intermediate pulley means being disposed intermediate said drive pulley means and said driven pulley means, said displacement mechanism being connected to said arm member such that said displacement mechanism is able to pivotally displace said arm member about said pivot axis of said arm member such that said saw is displaceable between a first position and a second position, said drive belt means having a first end and a second end, said first end engaging said drive pulley means, said second end engaging said driven pulley means, said drive belt means defining a first flight side and an opposed second flight side, said first and second flight sides each being connected respectively to said first and second ends, said drive belt means simultaneously engaging said drive pulley means, said intermediate pulley means and said driven pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second positions, said intermediate pulley means having a diameter larger than the diameter of the drive pulley means and of the driven pulley means.
2. A rotatable saw apparatus comprising a machine frame, an arm member, said arm member being pivotably mounted on said machine frame such that said arm member is pivotable about a pivot axis a circular saw rotatably mounted on said arm member a driven pulley means rotatably mounted on said arm member and connected to said saw for the rotation thereof a drive pulley means drivingly connected to a motor, said drive pulley being disposed at a location spaced apart from said arm member, an intermediate pulley means disposed intermediate said drive pulley means and said driven pulley means, said intermediate pulley means being configured and disposed such that its axis of rotation is co-axially aligned with said pivot axis of said arm member a displacement mechanism and a drive belt means said displacement mechanism being connected to said arm member such that said displacement mechanism is able to pivotally displace said arm member about said pivot axis of said arm member such that said saw is displaceable between a first position and a second position, said drive belt means having a first end and a second end, said first end engaging said drive pulley means, said second end engaging said driven pulley means, said drive belt means defining a first flight side and an opposed second flight side, said first and second flight sides each being connected respectively to said first and second ends, said drive belt means simultaneously engaging said drive pulley means, said intermediate pulley means and said driven pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second positions, said arm member having opposed first and second arm ends, said pivot axis being disposed between said first and second arm ends so as to divide the arm member into a first side terminating in said first arm end and a second side terminating in said second arm end, said saw being mounted to said first side of the arm member and said displacement mechanism being connected to said second side of the arm member.
3. A rotatable saw apparatus as defined in claim 2 wherein said intermediate pulley means has a diameter larger than the diameter of the drive pulley means and of the driven pulley means.
4. The rotatable saw apparatus of claim 2 wherein said saw is mounted adjacent said first arm end of the arm member and said displacement mechanism is connected to said arm member adjacent to the second arm end of the arm member.
5. The rotatable saw apparatus of claim 2 wherein said drive belt means, said drive pulley means, said intermediate pulley means and said driven pulley means are disposed and configured such that said first and second flight sides each engages said intermediate pulley when said saw is in said first and second positions and when said saw is displaced between said first and second positions.
6. The rotatable saw apparatus of claim 2 wherein said saw is mounted adjacent said first arm end of the arm member, wherein said displacement mechanism is connected to said arm member adjacent to the second arm end of the arm member, wherein said drive belt means, said drive pulley means, said intermediate pulley means and said driven pulley means are disposed and configured such that said first and second flight sides each engages said intermediate pulley means when said saw is in said first and second positions and when said saw is displaced between said first and second position, and wherein said intermediate pulley means and said arm member are rotationally mounted on a common shaft.
7. A rotatable saw apparatus as defined in claim 6 wherein said intermediate pulley means has a diameter larger than the diameter of the drive pulley means and of the driven pulley means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2255791 CA2255791C (en) | 1998-12-14 | 1998-12-14 | Rotatable saw apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2255791 CA2255791C (en) | 1998-12-14 | 1998-12-14 | Rotatable saw apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2255791A1 CA2255791A1 (en) | 1999-08-08 |
| CA2255791C true CA2255791C (en) | 2002-07-09 |
Family
ID=4163086
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2255791 Expired - Lifetime CA2255791C (en) | 1998-12-14 | 1998-12-14 | Rotatable saw apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2255791C (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102007022912B4 (en) * | 2007-05-14 | 2009-05-07 | Raimann Holzoptimierung Gmbh & Co.Kg | Device for sawing boards |
| CN114608843B (en) * | 2022-05-12 | 2022-07-26 | 中汽研汽车检验中心(宁波)有限公司 | Driving device with tape collecting function and tape collecting method |
-
1998
- 1998-12-14 CA CA 2255791 patent/CA2255791C/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CA2255791A1 (en) | 1999-08-08 |
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