Patent Abstract:
A holesaw mandrel assembly has a mandrel body with a first end to be coupled with a drill motor and a second end extending from the body. The second end receives a holesaw. The first member is positioned on the second end. The first member is axially movable on the second end. A friction surface is on the first member. The friction surface is adapted to contact a base surface of the holesaw such that upon contact with the friction surface, the holesaw is fixed in position. The friction surface moves between a first contact position and a second release position. A mechanism on the first member moves the friction surface between the first and second position.

Full Description:
FIELD 
     The present disclosure relates to holesaws and, more particularly, to a mandrel assembly which receives holesaws. 
     BACKGROUND 
     Various types of holesaw mandrel assemblies exist in the art. The assemblies are concerned with a quick release device in order to readily remove the holesaw from the mandrel assembly after use. Various types of mechanisms have been utilized in order to secure the holesaw onto the mandrel assembly, all of which enable the holesaw to be removed. Some of these mandrel assemblies utilize pins or the like which fit into the base of the holesaw. The pins hold the holesaw in position during rotation and cutting. However, since the holesaw is not torque down onto the collar adjacent the threaded spud, the pins can be removed from the base of the holesaw and the holesaw can be easily rotated and removed from the threaded spud. 
     When smaller diameter holesaws are utilized, the base of the holesaw does not include holes to receive the pins on the mandrel assemblies. This is due to the fact that the diameter of the base is too small to register with the pins. Also, during use, due to the threaded engagement of the spud with the small holesaw, the holesaw is torqued down onto the collar of the mandrel assembly. Accordingly, a wrench or the like is required to loosen the holesaw from the mandrel collar in order to remove the holesaw from the mandrel assembly. The art does not provide a small holesaw mandrel which enables the user to quickly remove, by hand, the holesaw from the mandrel assembly. Thus, it is desirable to have a mandrel assembly which enables the quick release of small diameter holesaws. 
     SUMMARY 
     The present disclosure provides the art with a holesaw mandrel assembly which enables a quick release of holesaws from the mandrel assembly. The present holesaw mandrel assembly provides a friction face that abuts the holesaw. The friction face axially moves away from the holesaw into a release position. The holesaw assembly enables the friction face to move automatically back to its original position. The holesaw mandrel assembly provides a push button action to enable the axial movement of the friction face. 
     According to a first aspect of the disclosure, a holesaw mandrel assembly comprises a mandrel having a body with a first end to couple with a drill motor. A second end extends from the body. The second end includes a thread to receive a holesaw. A first member is positioned on the second end. The first member axially moves on the second end. A friction surface is on the first member. The friction surface is adapted to contact or engage a base surface of the holesaw such that upon contact with the friction surface, the holesaw is fixed in position. The friction surface moves between a first contact and second release position. A mechanism, on the first member, moves the friction surface between the first and second positions. The mechanism is biased to return the first member to its first position from its second or released position. The mechanism includes a second member movable transverse to the mandrel axis to enable the axial movement of the first member. At least one roller is positioned between the first and second member. The second member includes a body including at least one recess to receive the at least one roller. The mechanism includes at least one cage to retain the at least one roller. 
     According to a second aspect of the disclosure, a holesaw mandrel assembly comprises a mandrel which includes a body with a first end to couple with a drill motor. A second end extends from the body. The second end includes a thread to receive a holesaw. A first member is on the second end. The first member axially moves on the second end. A push button mechanism is coupled with the first member. At least one roller is associated with the push button mechanism. The at least one roller is in contact with the push button member. The push button member moves between a first and a second position to enable the first member to move axially along the second end. When the push button mechanism is in its first position, the first member is fixed so that a holesaw may be screwed onto the thread and abuts the first member to secure a holesaw in a use position on the first member. When the push button mechanism is moved to its second position, the first member moves axially away from the holesaw to enable the holesaw to be easily removed from the thread. The push button mechanism includes at least one recess which is adjacent to the at least one roller. When the push button mechanism is in its second position, the at least one roller is positioned in the at least one recess. A plurality of rollers is present with at least two rollers sandwiching the push button mechanism. A pair of friction plates are positioned such that the at least two roller each contact one of the pair of friction plates. A biasing member moves the push button mechanism between the first and second positions. 
     According to a third aspect of the disclosure, a holesaw mandrel assembly comprises a mandrel with a body which includes a first end to couple with a drill motor. A second end extends from the body. The second end includes a thread to receive a holesaw. A first member is on the second end. The first member axially moves on the second end. A friction surface is on the first member. The friction surface is adapted to contact the base surface of the holesaw such that upon contact with the friction surface, the holesaw is fixed in position. The friction surface moves between a first contact and a second release position. A mechanism is coupled with the first member to move the friction surface between the first and second positions. The mechanism comprises a push button member extending through the first member. The push button member includes a body member with two side faces with a plurality of recesses on each side face. A plurality of rollers, equal in number to the plurality of recesses, is positioned on the two sides of the body member. The plurality of rollers is positioned adjacent to the plurality of recesses. When the plurality of rollers is on the side faces, the first member is in its first position. When the rollers are in the recesses, the first member is in the second position. The push button member moves between the first and second positions, via a spring, wherein the plurality of rollers move in and out of the adjacent recesses. A pair or cages retain the roller in position. A pair of friction members are positioned adjacent the rollers. One friction member is on each side of the push button member and in contact with the rollers. 
     Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
         FIG. 1  is a perspective view of a holesaw mandrel. 
         FIG. 2  is a cross section view of the mandrel of  FIG. 1  in a first position. 
         FIG. 3  is a view like  FIG. 2  in a second position. 
         FIG. 4  is an exploded perspective view of the mandrel of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. 
     Turning to the figures, a holesaw mandrel is illustrated and designated with the reference numeral  10 . The mandrel assembly  10  includes a mandrel  12 , a first movable member  14 , and a mechanism  16  for moving the first member  14  between a first and second position. The mandrel  12  includes a body  18  with a first projecting end  20  and a second extending end  22 . The first projecting end  20  is cylindrical and may have an outer polygonal surface to connect the mandrel  12  with a rotating tool, such as a drill. The body  18  has a first cylindrical portion  24  and a larger plate portion  26 . The first portion  24  includes an aperture  28  to receive a fastener  30  which retains a pilot drill bit  32  in a bore  34 . The pilot drill bit  32  extends through the second extending member  22 . The second plate  26  has an overall elongated D-shape and includes a flat receiving surface  36 . 
     The second extending end  22  of the mandrel  12  includes a first cylindrical portion  40  and a threaded spud  42 . The threaded spud  42  receives a holesaw  38  in a conventional manner. The first cylindrical portion  40  extends from the larger second plate portion  26 . 
     The first member  14  has an overall cup shaped configuration. The first member includes a bore  48  through the base portion  50  of the cup shaped first member  14 . The base portion  50  includes a friction face  52  which receives the base of the holesaw  38  as seen in  FIG. 2 . The bore  48  enables the first member  14  to be positioned on the second end  22  of the mandrel  12 . The bore  48  opens into a larger cylindrical open space  54  inside the cylindrical wall  56  of the cup shaped first member  14 . The wall  56  includes an arcuate cut-out portion  58  as well as a bore  60  which receives a portion of the moving mechanism  16 . A back plate  62  is connected with the wall  56 . The back plate  62  is substantially parallel to the base portion  50 . The back plate  62  includes a pair of apertures  64  which receive fasteners  68  to retain a securement plate  70  onto the first member  14 . The securement plate  70  includes an aperture  71  to receive the mandrel cylindrical portion  24  as well as a pair of apertures  73  to receive fasteners  68 . The back plate  62  includes a cut-out  72 , having an overall elongated D-shape, to receive the moving mechanism  16  and the mandrel plate portion  26 . 
     The mechanism  16 , which moves the first member  14  between a first and second position, is positioned transverse to the longitudinal axis  74  of the mandrel  12 . The mechanism  16  includes a push button  80  which is positioned in the aperture  60 . The push button  80 , through its movement which will be explained later, enables the axial movement of the first member  14  on the mandrel  12 . The push button  80  is coupled with or unitarily formed with a plate member  82 . The plate member  82  includes a projection  84  which seats inside of the push button  80 . The plate member  82  has an overall rectangular annular shape with an elongated elliptical opening  86  in the middle of the plate member  82 . The elliptical opening  86  receives the mandrel second end  22 . The plate member  82  includes a pair of side faces  88  and  90 . The side faces  88  and  90  each include at least one and preferably a plurality of recesses  92 . Also, the plate member  82  includes a tail  94  and recess  95  which are associated with the biasing spring  96 . The spring  96  biases the push button  80  between its first and second positions. 
     At least one and preferably a plurality of rollers  98  are positioned on each side face  88  and  90  of the plate member  82 . The rollers  98 , when the push button  80  is in a first position as seen in  FIG. 2 , rest on the planar side faces  88 ,  90  of the plate member  82 . In the push button  80  second position as seen in  FIG. 3 , the rollers move from the planar side faces  88 ,  90  into the recesses  92 . 
     A pair of cages  100  and  102  holds the rollers  98  in position. The cages  100  and  102  are identical and the disclosure of one equally applies to the other. The cages  100 ,  102  have an overall rectangular shape with an elliptical aperture  104 , to receive the mandrel second end  22 , in the middle of the body  106 . The body  106  has two sides  108  and  110 , each of which includes at least one, and shown with a pair of apertures  112 . The apertures  112  receive the rollers  98  in the cages  100  and  102 . A projecting member  114  extends from the body  106  into the push button member  80 . Also, a cut out  116  is opposite the projecting member  114  to enable the biasing spring  96  to seat in the cut out portion  116 . 
     A pair of friction plates  118  and  120  sandwiches the rollers and cages against the plate  82 . The friction plates  118  and  120  are substantially identical and the explanation with respect to one applies to both. The friction plates  118  have an overall D shape with a circular aperture  122 . The aperture  122  is circular and sized to fit onto the second extending member  22  of the mandrel  12 . Thus, unlike the plate  82  and cages  100 ,  102 , the friction plates  118 ,  120  are unable to move laterally with respect to the extending member  22 . The friction plates  118  and  120  have flat planar surfaces  124  and  126 . The flat planar surfaces  124 ,  126  provide a rolling surface for the rollers  98 . One of the flat planar surfaces of the plate  118  abuts the flat surface  36  of the second plate member  26  of the mandrel  12  while the other abuts the flat inside surface of base  50 . It should be noted that the friction plates may be removed and the flat surface  36  and inside surface of the base  50  may be used as the rolling surfaces for the rollers  98 . 
     The friction plates  118  and  120  as well as cages  100  and  102  with rollers  98  sandwiching plate  82  are all positioned onto the extending member  22  of the mandrel  12 . This is best illustrated in  FIGS. 2 and 3 . The biasing spring  96  abuts one side of the wall  56  opposite to the aperture  60 . The push button  80  projects from the aperture  60  in the arcuate cut out portion  58 . The plate  70  and the screw  68  retain the mandrel  12  in an assembled position with the first member  14  and the moving mechanism  16 , positioned inside of the first member  14 , on the mandrel  12 . 
     A holesaw  38  is screwed onto spud  42  until it abuts the friction surface  52  of the first member  14  (see  FIG. 2 ). At this time, the holesaw  38  is in a use position abutting the friction surface  52  which receives the force from the holesaw  38  torque during operation. Once the holesaw  38  is used to drill a hole and a different holesaw is desired, the holesaw  38  is removed from the mandrel. In order to do this, push button  80  is moved inward tranversed to the longitudinal axis  74  of the mandrel  12 . As this occurs, plate  82  is moved laterally against the spring  96 . As the plate  82  continues to move, the cages  100  and  102  move laterally half the distance of the plate  82 . As the button  80  is fully depressed (see  FIG. 3 ), the rollers  98  fall into the recesses  92  in the plate  82 . As this happens, due to the force on the friction surface  52  of the first member  14  as well as the space created by the recesses  92 , the first member  14  moves away from a holesaw  38  as seen in  FIG. 3 . A gap  130  is created between the holesaw  38  and the friction surface  52  of the first member  14 . This enables the user to easily remove the holesaw  38  from the threaded spud  42 . Once the force is removed from the push button  80 , the spring  96  returns the push button  80 , as well as the plate  82  and cages  100 ,  102 , to their original position. Since the spring  96  is able to move the plate  82  as well as the cages  100 ,  102 , it enables the cages  100 ,  102  and plate  82  to align and register with one another so that the rollers  98  are in a proper first position with respect to the recesses  92  as shown in  FIG. 2 . Thus, the mandrel assembly  10  is ready for its next use. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.

Technology Classification (CPC): 8