Patent Abstract:
A saw and/or saw frame including: an elongate substantially rigid back member and a swing arm pivotally connected to the back member so as to be rotatable between an extended position and a storage position; a handle with a first blade mount; the swing arm includes a second blade mount; the back includes a third blade mount disposed proximate to the swing arm; each of the first, second, and third blade mounts being constructed to engage one end of a removably mounted saw blade, with the first, second, and third blade mounts disposed to allow quick changes in blade configuration. The back member also has an elongate blade storage cavity accessible from above adapted to store at least one of the removably mounted saw blades and an auxiliary blade mounting mechanism configured to operatively mount an auxiliary blade extending forward from the frame.

Full Description:
BACKGROUND OF THE INVENTION 
   The present invention is directed generally to a handsaw formed from a frame and a removable main saw blade, where the main saw blade may be stored in the frame and the frame may support an auxiliary saw blade extending forward from the frame. 
   Numerous handsaw frames have been proposed and used through time. One typical saw frame structure is commonly referred to as a hacksaw frame. Hacksaw frames are generally U-shaped, with the relevant hacksaw blade operatively supported between forward and back downwardly extending frame portions. Examples of hacksaws of this general design can be found in U.S. Pat. Nos. 2,658,541; 2,767,751; and 3,636,997; and more recently in U.S. Pat. Nos. 5,471,752 and 6,230,412. While such hacksaws have been found useful in a variety of situations, there remains a need for alternative handsaw designs. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to a saw and/or saw frame comprising: an elongate substantially rigid back member, a handle portion, and a swing arm pivotally connected to the back member distal from the handle portion so as to be rotatable between an extended position generally transverse to the back member and a storage position generally parallel and aligned with the back member; the handle portion comprising at least a first blade mount; the swing arm comprising at least a second blade mount; the back member comprising at least a third blade mount disposed proximate to the swing arm; each of the first, second, and third blade mounts being constructed to engage one end of a removably mounted saw blade of a first type; wherein the first, second, and third blade mounts are disposed with the swing arm in the extended position such that a first distance between the first and second blade mounts substantially equals a second distance between the first and third blade mounts; the back member further comprising an auxiliary blade mount mechanism adapted to removably mount an auxiliary saw blade of a second type operatively extending forward from the frame; the back member further comprising a blade storage cavity adapted to store at least one of the saw blades. 
   The auxiliary blade mount mechanism may comprise an auxiliary blade mount, a bearing surface disposed forward and above the auxiliary blade mount, and an auxiliary blade holder disposed forward and below the auxiliary blade mount. The auxiliary blade mount, bearing surface, and auxiliary blade holder may all be disposed on a side opposite the third blade mount. The saw may further comprise a quick-release blade tensioning mechanism operative to releasably apply a selectable amount of tension to the first blade mount; and wherein the frame allows conversion from a first configuration with a removably mounted saw blade connected between the first and second blade mounts and a second configuration with the saw blade connected between the first and third blade mounts without adjustment to the selected amount of tension. The saw frame may further comprise a fourth blade mount; wherein the swing arm further comprises a fifth blade mount; wherein the fourth and fifth blade mounts are non-coplanar with the first, second, and third blade mounts, but are spaced a third distance from each other substantially equal to the first distance with the swing arm in the extended position. The saw frame may further comprise at least one magnet, preferably at least two magnets spaced from each other, associated with the blade storage cavity. The blade mounts may comprise a tapered pin. The back member may further comprise an upwardly opening channel in which the swing arm is disposed in the storage position. The back member may further comprise a downwardly extending lobe proximate the swing arm, the third blade mount disposed on the lobe, and the lobe may comprise a bearing surface that limits the rotational movement of the swing arm. A first theoretical line between the first and second blade mounts may be disposed substantially parallel to the back member and a second theoretical line between the first and third blade mounts may be disposed angled with respect to the back member. The saw may further comprise at least one saw blade. The handle portion may comprise a grip portion integrally formed with the back member. The handle portion may further comprise a quick-release blade tensioning mechanism operative to releasably apply tension to the first blade mount. The quick-release blade tensioning mechanism may comprise an operating lever pivotally mounted in an upper portion of the handle portion. The blade storage cavity may be elongate and accessible from above the blade storage cavity may be adapted to store more or more of the blades of the first or second types, optionally at least one of each type simultaneously. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a side view of a handsaw constructed in accordance with one embodiment of the present invention, with the main saw blade in the horizontal configuration (with vertical cant) and the swing arm in the extended position. 
       FIG. 2  shows a side view of the handsaw of  FIG. 1  with the main saw blade in the reduced space configuration and the swing arm in the storage position. 
       FIG. 3  shows a perspective view of the handsaw of  FIG. 1  from above and behind, showing the blade storage cavity. 
       FIG. 4  shows a side view from the opposite side of the handsaw of  FIG. 2  with the main blade removed and the auxiliary blade operatively mounted. 
       FIG. 5  shows a front view of the handsaw of  FIG. 1  with the main blade removed and the swing arm in the storage position. 
       FIG. 6  shows one embodiment of an auxiliary blade. 
       FIG. 7  shows a bottom view of the handsaw of  FIG. 1  with the main blade removed to show one possible arrangement of blade mounts. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The handsaw according to the present invention allows the user to easily change the orientation of the longitudinal axis of a main saw blade between two different configurations each supported on both ends by the saw&#39;s frame, to store at least one of such saw blades in the frame of the handsaw, and to attach an auxiliary saw blade to the frame that extends forward from the frame. For clarity of discussion, and without limiting the scope of the attached claims, the main saw blade (which when operatively mounted is supported on both ends) be may be referred to as a hacksaw blade, while the auxiliary saw blade (which when operatively mounted is not supported on both ends) may be referred to as a jabsaw blade. 
   As illustrated in the Figures, a handsaw according to one embodiment of the present invention, generally designated  5 , includes a frame  10  for supporting a hacksaw blade  2 . The frame  10  includes a spine (or back member)  20  that is generally elongate so as to separate a handle portion  100  from a swing arm  70 . While the spine  20  shown in  FIG. 1  is generally rectilinear along longitudinal axis  21 , the spine  20  may alternatively be sinuous, curved, or take any other shape known in the art. The spine  20  includes a pivot  30  and a swing arm storage cavity  32  toward its front (see  FIG. 3 ) for pivotally mounting and storing the swing arm  70  as discussed further below. The spine  20  further includes a downwardly extending lobe  22  on its lower side, proximate the swing arm  70 . The lobe  22  provides a location for a hacksaw blade mount  24  on the spine  20 , as discussed further below. In addition, the lobe  22  may advantageously provide a stop face  28  as a rotational positive stop for the swing arm  70 . 
   The swing arm  70  is pivotally mounted to the spine  20  so as to be rotatable between an extended position ( FIG. 1 ) and a storage position ( FIG. 2 ). In the extended position, the swing arm  70  extends downwardly with respect to the spine  20 , while in the storage position, the swing arm  70  is generally parallel and aligned with the spine  20 , and advantageously disposed in the swing arm storage cavity  32 . The swing arm  70  includes an upper portion  72 , a grip portion  80 , and a lower portion  90 . The upper portion  72  is rotatably coupled to the spine  20  via pivot  30 , which may be of any known type. Advantageously, the pivot  30  takes the form of a simple pin extending through two forwardly extending flanges on the spine  20  and a corresponding pin passage (not shown) through the upper portion  72  of the swing arm  70 . The upper portion  72  may further include a stop face  74  for abutting the lobe  22  in order to provide a positive stop for rotation of the swing arm  70 . Alternative means of limiting the amount of rotation of the swing arm  70  may alternatively be used. The grip portion  80  of the swing arm  70  advantageously includes a plurality of contoured finger indentations  84  and is advantageously covered by a suitable cushion material  82  such as a thermoplastic elastomer. The lower portion  90  of the swing arm  70  provides a location for operatively mounting the main hacksaw blade  2 . The lower portion  90  may include a notched area forming a main blade support face  92  with a main blade mount  94  disposed thereon. The lower portion  90  may advantageously also include a secondary blade supporting face  96  and secondary blade mount  98  for supporting the hacksaw blade  2  in a 45° orientation. 
   The handle  100  is connected to, or integrally formed with, the rear portion of the spine  20 . The handle  100  may include a grip area  102 , hand guard  106 , at least one blade mount  134 , and a blade tensioning mechanism  110 . The grip area  102  is intended to be gripped by the user&#39;s hand and may include a suitable cushion  104  if desired. The hand guard  106  is positioned in front of the grip area  102 , with an opening therebetween, and advantageously provides protection for the user&#39;s hand and additional rigidity for the frame  10 . The blade tensioning mechanism  110  includes a lever  112 , a pivot body  120 , and a connecting rod  114  running therebetween. The lever  112  is pivotally mounted at the upper portion of the handle  100  for movement between a closed/tension position generally parallel to the longitudinal axis  21  and an open/released position extending upward from the handle  100 . The rear portion of the lever  112  couples to the connecting rod  114 , which runs interiorly of the grip area  102  to the lower portion of the handle  100 . The connecting rod  114  operatively connects the lever  112  to the pivot body  120  (see  FIG. 4 ). The pivot body  120  is pivotally mounted to the middle area of the hand guard  106  and extends from that pivot point  122  down along the hand guard  106  (mostly interiorly) and back toward the grip  102 . The lower forward portion of the pivot body  120  includes a blade mounting area  130  that includes a main blade support face  132  with a main blade mount  134  thereon, and optionally a secondary blade support face  136  and secondary blade mount  138 . The rear portion of the pivot body  120  includes a hole through which the connecting rod  114  extends to engage a tension adjusting knob  116 . By changing the setting of the tension adjusting knob  116 , the “locked” position of the main blade mount  134  (and the optional secondary blade mount  138 ) may be adjusted, thereby adjusting the tension setting for the hacksaw blade  2 . This blade tension mechanism  110  is advantageously of the “over-center locking” type. 
   With the swing arm  70  down in the extended position, the distance L 1  between blade mount  134  and blade mount  94  on the swing arm  70  is substantially equal to distance L 2  between blade mount  134  and blade mount  24  on the lobe  22  of the spine  20 . This arrangement allows the hacksaw blade  2  to be easily changed from a normal horizontal mounting basically parallel to the spine  20  ( FIG. 1 ) to a reduced space mounting where the mounted hacksaw blade  2  is angled at angle α relative to the spine  20  ( FIG. 2 ) so as to reduce the front profile of the saw  5 , all without requiring an adjustment to the tension setting of the blade tension mechanism  110  via knob  116 . To achieve this, the user simply pulls up on the lever  112 , which releases tension on the blade  2 , decouples the forward end of the blade  2  from blade mount  94 , rotates the swing arm  70  to its storage position in swing arm storage cavity  32 , couples the forward end of the blade  2  to blade mount  24  on the lobe  22  of the spine  20 , and returns the lever  112  to the locked position. A reverse process can also be used to change from the reduced space mounting to the normal horizontal mounting when desired. This type of two-position frame  10  conversion is generally described in U.S. Pat. No. 6,606,795, the disclosure of which is incorporated herein by reference. 
   It is intended that blade mounts  24 ,  94 ,  134  will be disposed so as to all lie in one plane that advantageously includes the longitudinal axis  21  of the spine  20 ; these blade mounts  24 ,  94 ,  134  are intended for a “vertical” mounting of a hacksaw blade  2 . Likewise, the secondary blade mounts  98 ,  138  are intended to all lie in another plane that is angled 45° with respect thereto; these blade mounts  98 ,  138  are intended for a “45°” mounting of a hacksaw blade  2 . Further, while not required for all embodiments, the distance between blade mounts  98 ,  138  may advantageously also be substantially equal to L 1  with the swing arm  70  in the down position. Note that due to the presence of the auxiliary blade mounting mechanism  50 , discussed below, there may or may not be a blade mount on the spine  20  corresponding to the 45° blade mounting orientation, meaning that there may or may not be the ability to quickly change from the horizontal blade orientation to the angled orientation (i.e., front end of blade mounted to spine  20 , not swing arm  70 ) with the blade at a 45° cant in both orientations. 
   The spine  20  further includes a blade storage cavity  40  for storing extra hacksaw blades  2  or jabsaw blades  6 . The blade storage cavity  40  typically takes the form of a relatively deep slot formed in the upper surface of the spine  20 , that may or may not be connected to the swing arm storage cavity  32 . One or more magnets  44  may be mounted in the spine  20  so as to face the blade storage cavity  40 ; advantageously, there are two or more such magnets  44  at locations spaced from one another. In addition, an access aperture  42  on the side of the spine  20  may connect to the blade storage cavity  40 ; this access aperture  42  allows the user to visually see if a blade  2  is in the blade storage cavity  40  and to contact the blade  2  to urge the same out of the blade storage cavity  40 . It is believed advantageous if the blade storage cavity  40  has a relatively narrow cross section proximate the access aperture  42  so as to provide a resistance surface when the user is urging the blade  2  out of the blade storage cavity  40  with a finger. The rear portion of the blade storage cavity  40  may be enlarged if desired to aesthetically balance the swing arm cavity  32  and to provide additional access to any saw blades  2  stored in the blade storage cavity  40 . It should be noted that having an open top blade storage cavity  40  as shown in  FIG. 3  allows for one or more blades  2 ,  6  to be stored in the blade storage cavity  40  and to be added and/or removed from above. While not required for all embodiments, the blade storage cavity may advantageously be sized to allow the simultaneous storage of at least one hacksaw blade  2  and at least one jabsaw blade  6 . 
   The spine  20  further includes an auxiliary blade mounting mechanism  50  for supporting an auxiliary blade  6  that forwardly extends from the frame  10 . This auxiliary blade  6  may be used as a “jab saw” blade, and is therefore sometimes referred to herein as a jabsaw blade  6 , as indicated above. The auxiliary blade mounting mechanism  50  may include an auxiliary blade mount  68 , an auxiliary blade holder  60 , and a bearing surface  54 . The auxiliary blade mount  68  may be disposed on the lobe  22  in a position spaced rearwardly from the frontmost portion of the spine  20 . The blade holder  60  may be disposed forward of, and lower than, the auxiliary blade mount  68 . In some embodiments, the blade holder  60  may take the form of a simple screw arrangement that helps hold the auxiliary blade  6  against the side of the lobe  22 . The screw  62  may pass through a corresponding hole (not shown) in the lobe  22  to engage a nut  64 . This nut  64  may be fitted in a corresponding recess  26  in the lobe  22  and may advantageously be secured to the lobe  22 ; alternatively, the hole in the lobe  22  may be threaded. If desired, a washer or pressing plate  66  may also be used to aid in pressing the auxiliary blade  6  against the lobe  22 . Other forms of blade holders  60 , such as spring clips, quarter-turn fasteners, magnets, or the like may alternatively be used with the understanding that a primary purpose of the blade holder  60  is to aid in keeping the auxiliary blade  6  engaged with the auxiliary blade mount  68  during use. The bearing surface  54  is disposed forward and upward of the auxiliary blade mount  68 . The bearing surface  54  may advantageously be formed as the upper wall of a downwardly open longitudinally extending slot  52  on spine  20 . When operatively mounted, the auxiliary blade  6  juts forward from the frame  10  and is supported from above by the bearing surface  54  and from below by the blade holder  60 . The auxiliary blade mount  68  keeps the auxiliary blade  6  from moving longitudinally with respect to the frame  10  during use. It should be noted that the various portions of the auxiliary blade mounting mechanism  50  may advantageously be on the side of the spine  20  opposite that of the hacksaw blade mount  24  on the lobe  22  to avoid interfering with the main hacksaw blade mounting functions. 
   The jabsaw blade  6  may take the form shown in  FIG. 6 . Because this jabsaw blade  6  is expected to be subjected to significant loads and is supported in a cantilever fashion, the jabsaw blade  6  is typically much thicker and shorter than a conventional hacksaw blade  2 . With this in mind, the blade storage cavity  40  may advantageously be sized to accommodate the jabsaw blade  6  when not mounted to the frame  10  via the auxiliary blade mounting mechanism  50 . 
   While the disclosure above has been in terms of one embodiment of a lever-actuated blade tensioning mechanism  110 , this particular mechanism is not required in all embodiments. Indeed, any one of a variety of blade tensioning mechanisms may be used, such as one operating according to any of the principles described in U.S. Pat. Nos. 1,187,460; 1,517,827; 3,636,997; 3,822,731; 4,349,059; 4,367,779; 4,466,471; 5,673,488; or 6,134,791. Additionally, the disclosures of U.S. patent applications Ser. Nos. 29/203,985 (filed 22 Apr. 2004) and 29/204,512 (filed 29 Apr. 2004) are incorporated herein by reference. 
   The various blade mounts  24 ,  94 ,  134 ,  98 ,  138 ,  68  discussed herein may advantageously take the form of a short slightly tapered, but otherwise cylindrical, pin that is press fitted into the corresponding location. Alternatively, the blade mounts  24 ,  94 ,  134 ,  98 ,  138 ,  68  may be integrally formed with the corresponding components or take other forms known in the art. 
   The majority of various parts of the frame  10  may be formed of aluminum, steel, various plastics, or other suitable rigid materials. As mentioned above, some or all of the grip surfaces  82 ,  102  may optionally be coated with a suitable cushioning material known in the art. 
   The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

Technology Classification (CPC): 1