Patent Publication Number: US-2020276660-A1

Title: Band saw

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to co-pending U.S. Provisional Patent Application No. 62/812,638, filed Mar. 1, 2019, the entire content of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a handheld saw, and, more particularly, to a portable band saw. Handheld band saws are used to cut a variety of workpieces, such as pipes, rods, studs, and blocks. A cordless, compact band saw allows for cutting operations in tight spaces or awkward angles for plumbing, electrical, remodeling, and HVAC applications. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention provides a handheld band saw includes a housing, a handle coupled to the housing and configured to be grasped by a user during a cutting operation, a motor supported by the housing, and a drive wheel assembly rotationally driven by the motor. The drive wheel assembly is at least partially disposed within the housing. The band saw further includes a saw blade driven by the drive wheel assembly. The saw blade is configured to cut a workpiece during the cutting operation. The band saw further includes a pipe reamer attachment coupled to the drive wheel assembly. The pipe reamer attachment is configured to deburr the workpiece after completion of the cutting operation. 
     In another aspect, the invention provides a handheld band saw including a housing, a handle supported by the housing and configured to be grasped by a user during a cutting operation, a motor supported by the housing, and a drive wheel assembly rotationally driven by the motor. The drive wheel assembly is at least partially disposed within the housing. The band saw further includes a saw blade driven by the drive wheel assembly. The saw blade is configured to cut a workpiece during the cutting operation. The band saw further includes a shoe coupled to the housing adjacent the saw blade. The shoe is configured to support a workpiece during the cutting operation. The shoe includes a slide mechanism for adjusting the shoe along a shoe axis that is perpendicular to the saw blade, and a detent mechanism having a tooth that is selectively receivable in one of a plurality of notches for maintaining the shoe in a discrete position along the shoe axis. The tooth has a cam surface shaped to permit removal of the tooth from one of the plurality of notches when a force is applied to the shoe in the direction of the shoe axis, thereby causing the shoe to move along the shoe axis. 
     In yet another aspect, the invention provides a handheld band saw including a housing, a handle supported by the housing and configured to be grasped by a user during a cutting operation, and a motor supported by the housing. The band saw further includes a drive wheel assembly that is at least partially disposed within the housing. The band saw further includes a saw blade driven by the drive wheel assembly and configured to cut a workpiece during the cutting operation. The band saw further includes a drive assembly positioned between the motor and the drive wheel assembly. The drive assembly is configured to transfer torque from the motor to the drive wheel assembly, causing the drive wheel assembly and the saw blade to rotate. The drive wheel assembly includes a wheel having a recess in which a portion of the drive assembly is received to shorten an overall length of the motor, drive assembly, and drive wheel assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a handheld band saw. 
         FIG. 2  is an exploded view of a drive wheel assembly of the band saw of  FIG. 1 , illustrating a pipe reamer attachment removably attached thereto. 
         FIG. 3  is an exploded view of an alternative embodiment of a drive wheel assembly of the band saw of  FIG. 1 , illustrating a pipe reamer attachment removably attached thereto. 
         FIG. 4  is a cross-sectional view of yet another embodiment of a drive wheel of the band saw of  FIG. 1 , illustrating a pipe reamer attachment removably attached thereto. 
         FIG. 5  is perspective view of a shoe of the band saw of  FIG. 1 , illustrating a slide mechanism that enables the shoe to move along a shoe axis. 
         FIG. 6  is an enlarged plan view of the slide mechanism of  FIG. 5 , illustrating a detent mechanism of the slide mechanism. 
         FIG. 7  is a cross-sectional view of a motor of the band saw taken along line  7 - 7  of  FIG. 1 . 
         FIG. 8  is a perspective view of the motor of the band saw, illustrating a recess within a motor fan. 
         FIG. 9  is a plan view of the motor of  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates a band saw  10  including a frame or housing  14  supporting a motor  18  and a gear box  22  ( FIG. 7 ). In the illustrated construction of the band saw  10 , the motor  18  is configured as a DC brushless motor, and the band saw  10  includes a removable, rechargeable battery  26  for supplying power to the band saw  10 . The motor  18  is drivingly connected to a drive assembly  30  through a gear box  22 . The motor  18 , the drive assembly  30 , and the gear box  22  are supported by the housing  14 . The drive assembly  30  may include any of a number of bearing arrangements and different gear train arrangements configured to provide a low-speed, high-torque output from the high-speed, low-torque input provided by the motor  18 . The motor  18  and the drive assembly  30  are operable to drive a continuous band saw blade  34  to cut a workpiece ( FIG. 1 ). 
     With continued reference to  FIG. 1 , the housing  14  includes a main handle  38  with a trigger  42  to provide power to the band saw  10 . The trigger  42  is disposed adjacent a gripping portion  44  of the handle  38  where a user grasps the band saw  10 . In the illustrated construction of the band saw  10 , the battery  26  is supported by the main handle  38  and is an 18-volt power tool battery  26 . In other embodiments, the battery  26  may be supported on the housing  14 . The trigger  42  is operable to control operation of the motor  18 . Specifically, the battery  26  selectively supplies power to the motor  18  when the trigger  42  is actuated. The housing  14  of the band saw  10  also includes a deck  46  and a guard  50  coupled to the deck  46 . A combination of the deck  46  and the guard  50  defines an opening or U-shaped cavity  54 . The guard  50  includes a lip  52  that provides a recessed area  56  ( FIG. 7 ) in which the band saw blade  34  is positioned. The guard  50  substantially covers the band saw blade  34  when the blade  34  is in a shielded position (i.e., when the blade  26  is outside of a cut zone  58 ;  FIG. 1 ). However, the U-shaped cavity  54  enables the band saw blade  34  to be in an exposed position (i.e., when the blade  26  passes through the cut zone  58 ;  FIG. 1 ). In the exposed position, the blade  34  is fully exposed and unobstructed by the guard  50 , allowing workpieces to be cut when entering the cut zone  58 . 
     With reference to  FIGS. 1-4 , the deck  46  includes a motor support portion  62  and a separate motor cover  66  that together enclose the motor  18 . The band saw  10  further includes a drive wheel assembly  68  that supports and drives the saw blade  34 . The drive wheel assembly  68  includes a drive wheel  70  that is directly driven by the motor  18  and a driven wheel  74  that is driven by the drive wheel  70  via the saw blade  34 . The outer peripheral surface and the interior side of the drive wheel  70  and the driven wheel  74  are covered by the deck  46  and the guard  50 . The drive wheel  70  rotates about a drive wheel axis  78  ( FIGS. 2-4 ) defined by a drive wheel spindle  82  ( FIG. 7 ). The drive wheel spindle  82  is rotationally supported by bearings  84  of the drive assembly  30 . The drive wheel  70  is drivingly connected to the motor  18  via the gear box  22 , the drive assembly  30 , and the drive wheel spindle  82 . In the illustrated construction of the band saw  10 , the rotational axis  80  of the motor  18  is coaxially aligned with the drive wheel axis  78 . In other embodiments, the rotational axis  80  and the drive wheel axis  78  may be parallel or at some other oblique angle relative to each other. A tire  86  is coupled to the outer peripheral surface of each of the wheels  70 ,  74  (although only one of which is shown). Each tire  86  grips the saw blade  34  to drive motion thereof. 
     With reference to  FIG. 2 , the band saw  10  further includes a pipe reamer attachment  90   a  that is coupled to and driven by the drive wheel assembly  68 . Although the pipe reamer attachment  90   a  of the illustrated embodiment is coupled to the drive wheel  70 , in other embodiments, the pipe reamer attachment  90   a  may alternatively be coupled to the driven wheel  74 . With the pipe reamer attachment  90   a  being coupled to the band saw  10 , a user can both cut and ream (i.e., deburr) a pipe with a single tool. In one embodiment, the pipe reamer attachment  90   a  is removably coupled to the drive wheel  70 , while in other embodiments, the pipe reamer attachment  90   a  may be permanently coupled to or integrated as part of the drive wheel  70  ( FIG. 4 ). In this embodiment, the pipe reamer attachment  90   a  is coupled to the drive wheel  70  via a quick disconnect coupling  94 , as shown in  FIG. 2 . The quick disconnect coupling  94  includes spring detents  98  that mechanically interface with corresponding projections  102  to maintain the pipe reamer attachment  90   a  on the drive wheel  70 . More specifically, when attaching the pipe reamer attachment  90   a  to the drive wheel  70 , the projections  102  slide along the spring detents  98  to temporarily deform (i.e., flex) the spring detents  98 . Once the projections  102  slide beyond the spring detents  98 , the spring detents  98  rebound and create a mechanical interference between the projections  102  and the spring detents  98  to inhibit the piper reamer attachment  90   a  from being removed from the drive wheel  70 . During a reaming operation, the drive wheel  70  is driven, for example, in a clockwise direction, while the pipe reamer attachment  90   a  is coupled to the drive wheel  70  by rotating the pipe reamer attachment  90   a , for example, in a counter-clockwise direction so as to inhibit the pipe reamer attachment  90   a  from disconnecting from the drive wheel  70  during operation. The pipe reamer attachment  90   a  includes an annular shroud  104   a  that accommodates pipe ranging from ⅓ inches in diameter to 1 inch in diameter. In other embodiments, the pipe reamer attachment  90   a  may accommodate pipe having a different diameter. 
       FIG. 3  illustrates another embodiment of a pipe reamer attachment  90   b  that is coupled to the drive wheel  70  via a helical thread pattern  106 . Specifically, the drive wheel  70  includes a helical thread pattern  106  that engages with a corresponding thread pattern  106  on the piper reamer attachment  90   b . Again, the pipe reamer attachment  90   b  is rotatably coupled to the drive wheel  70  in an opposite direction of the direction of rotation of the drive wheel  70  to inhibit the pipe reamer attachment  90   b  from disconnecting from the drive wheel  70  during operation. The pipe reamer attachment  90   b  includes an annular shroud  104   b  that accommodates pipe ranging from ⅓ inches in diameter to 1 inch in diameter. In other embodiments, the pipe reamer attachment  90   b  may accommodate pipe having a different diameter. 
       FIG. 4  illustrates yet another embodiment of a pipe reamer attachment  90   c  that is integrated as part of the drive wheel  70 . In other words, the pipe reamer attachment  90   c  and the drive wheel  70  are formed as a single component that is directly coupled to the drive wheel spindle  82 . The pipe reamer attachment  90   c  may also be recessed within the drive wheel  70 , such that the pipe reamer attachment  90   c  does not extend or extends only slightly beyond the drive wheel  70 , as shown in  FIG. 4 . Still, the pipe reamer attachment  90   c  includes an annular shroud  104   c  that accommodates pipe ranging from ⅓ inches in diameter to 1 inch in diameter. In other embodiments, the pipe reamer attachment  90   c  may accommodate pipe having a different diameter. 
     Each pipe reamer attachment  90   a ,  90   b ,  90   c  includes a blade  108  for engaging and removing a burr formed on the end of a pipe after the blade  34  has cut the pipe. The blade  108  is disposed within the annular shroud  104   a ,  104   b ,  104   c  to prevent the blade  108  from being exposed from the exterior of the shroud  104   a ,  104   b ,  104   c . The blade  108  of the illustrated embodiment is a multi-tiered blade, where each tier is capable of engaging a different sized pipe, such as pipes ranging from ⅓ inches in diameter to 1 inch in diameter. In other embodiments, the blade  108  may alternatively be three separate blades. 
     With reference to  FIGS. 5 and 6 , the band saw  10  further includes a shoe  110  having a support surface  114  against which a workpiece is abutted during a cutting operation and a slot  116  through which the saw blade extends. The shoe  110  is adjacent the cut zone  58 . The shoe  110  is adjustable along a shoe axis  118  that extends substantially parallel with the saw blade  34 . By adjusting the shoe  110  along the shoe axis  118 , the support surface  114  is moveable to support and accommodate pipes of varying diameters. The shoe  110  includes a slide mechanism  122  with an actuator  124  that, when depressed, allows a user to move the shoe  110  between a retracted position and an extended position along the shoe axis  118 . The slide mechanism  122  maintains the shoe  110  in different predefined positions between the retracted and extended positions via a detent mechanism  125  ( FIG. 6 ). Specifically, the detent mechanism  125  includes a tooth  126  that is actuated via the actuator  124 , and a plurality of notches  128  that selectively receive the tooth  126  to maintain the shoe  110  in various predefined positions. When the tooth  126  is in an extended position (as shown in  FIG. 6 ), the tooth is received in one of the notches  128  and inhibits the shoe  110  from moving along the shoe axis  118 . In contrast, when the tooth  126  is in a retracted position, the tooth  126  is removed from one of the notches  128  thereby enabling the shoe  110  to move along the shoe axis  118 . 
     However, the detent mechanism  125  is designed in a cam-like manner such that the tooth  126  has a cam surface  127  shaped to permit the tooth  126  to be removed from the notch  128 , without depressing the actuator  124 , and moved to the retracted position when a sufficient upward force is exerted on the shoe  110  (from the frame of reference of  FIGS. 5 and 6 ). In this case, the shoe  110  retracts to the retracted position in response to a sufficient force being exerted upon the shoe  110 . An impact force proportionate to dropping the band saw  10  from a distance greater than approximately two inches above a ground surface is sufficient to cause the shoe  110  to retract to the retracted position when the impact force is exerted on the shoe  110 . The resulting impact force exerted upon the shoe  110  overcomes the biasing force of the detent mechanism  125 , allowing the shoe  110  to retract via the slide mechanism  122 . When the band saw  10  is dropped from a distance less than approximately two inches above a ground surface, the shoe  110  remains in position without retracting to the retracted position because the impact force exerted on the shoe  110  is not sufficient to overcome the biasing force of the detent mechanism  125 . The slide mechanism  122  is designed to avoid causing damage to the shoe  110  when the band saw  10  is inadvertently dropped. 
     With reference to  FIGS. 7-9 , the drive wheel  70  further includes a recess  130  on the interior side adjacent the motor  18 . The recess  130  accommodates a portion of the drive assembly  30 , as shown in  FIG. 7 . Also, a top rotor bearing  134  is accommodated within a recess  138  of a motor fan  142 , as shown in  FIGS. 7-9 , and mounted within a corresponding pocket  144  in the motor cover  66  ( FIG. 7 ). As such, the motor cover  66  and the motor fan  142  are spaced apart just enough to avoid mechanical interference, but the gap therebetween is otherwise negligible. The purpose of the recess  130  and the recess  138  is to consolidate the configuration of the motor  18 , the gearbox  22 , and the drive assembly  30  as much as possible so the motor cover  66  protrudes from the deck  46  as little as possible. By reducing the overall length L between the motor  18 , and the drive wheel assembly  68  measured along the rotational axis  80 , the band saw  10  is more ergonomic and reduces torque exerted on a user during a cutting and reaming operation. In some embodiments, the overall length L is between 2 inches and 3 inches. And, in some embodiments, the overall length is no more than 2.5 inches. 
     Various features of the invention are set forth in the following claims.