Abstract:
A point driver is provided that comprises a body, a selectively operable actuator, a pushplate connected to the actuator, and a head. The head includes a channel disposed between a first section and a second section. At least a segment of the channel follows an arcuate path. The head is aligned with the actuator so that a portion or all of the pushplate can be driven by the selectively operable actuator through at least a portion of the channel.

Description:
This application claims the benefit of U.S. Provisional Application No. 60/350,172, filed Jan. 15, 2002, which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates to tools and fluid powered drivers in general, and to tools for driving framer&#39;s points, or similar fasteners used for picture framing in particular. 
     2. Background of the Invention 
     Artwork, bills, and placards are often mounted within a frame for support and protection. The frame includes an opening surrounded by a rabbetted edge that is open to rear face of the frame. A transparent panel consisting of glass or plastic is positioned contiguous with the rabbetted edge. The artwork, bill, placard or the like, is placed behind the transparent panel. A backing panel is placed on the opposite side of the artwork for protection and support. The glass panel, artwork, and backing panel (i.e., “display panels”) are typically held in place by a plurality of glazier&#39;s points (sometimes referred to as “framer&#39;s” points). Each of the points is driven into the frame contiguous with or in close proximity to the outermost panel to minimize movement of the panels relative to the frame. Some points are rigid and are intended to permanently secure the panels relative to the frame. Flexible points, on the other hand, can be bent aside to permit removal of the panels. Points are relatively small and it is desirable to position them as close as possible to the panels to minimize movement of the panels. Some desirable frame materials are quite hard making it difficult to drive a point into the frame. 
     To facilitate the job of driving a point, it is known to utilize a mechanically actuated device for driving points. U.S. Pat. No. 4,699,307 is an example of such a driver that is operator powered. Other mechanical drivers utilize a powered actuator (e.g., electrically, pneumatically, hydraulically, magnetically powered, etc.) to drive the point into the framing material. 
     A critical aspect of any driver is how close it can drive a point to the outermost panel; e.g., the backing board. Ideally, the point is driven into the frame so as to be contiguous with the outermost panel. In reality, however, the point must be supported and guided by the driver as the point is being driven into the frame. The support and guide structure of most prior art drivers includes a nosepiece having a channel through which the point is driven, disposed between a pair of walls. To secure the panels relative to a frame, a lateral surface of the nosepiece is placed on or near the outer most panel and the tip of the nosepiece is placed in contact with the frame. One of the walls of the nosepiece is disposed between the channel and the outermost panel. If the outer surface of the nosepiece wall is skewed from the channel (i.e., a point-shaped nosepiece), the point is driven into the frame skewed and separated from the outermost panel by the thickness of the nosepiece wall. If the outer surface of the nosepiece is parallel to the channel, the point is driven into the frame parallel to the outermost panel, separated from the outermost panel by the thickness of the nosepiece wall. In both instances, the point is likely to be undesirably separated from the outermost panel and must be bent inwardly to achieve the desired effect. Undesirable separation between the point and the outermost panel is particularly problematic for most prior art powered drivers because the size of the actuator (e.g., pneumatic cylinder, coil. etc.) limits how close the driver can be positioned relative to the outer most panel. 
     What is needed, therefore, is a driver that can drive a point into a frame in close proximity to or contiguous with the outermost of the display panels. 
     DISCLOSURE OF THE INVENTION 
     According to the present invention, a point driver is provided that comprises a body, a selectively operable actuator, a pushplate connected to the actuator, and a head. The head includes a channel disposed between a first section and a second section. At least a segment of the channel follows an arcuate path. The head is aligned with the actuator so that a portion or all of the pushplate can be driven by the selectively operable actuator through at least a portion of the channel. 
     An advantage of the present invention is that a powered point driver is provided that can drive a point into a frame so that substantially all of the exposed point is in close proximity to or contiguous with the outermost panel of display materials. Currently available pneumatically or otherwise powered point drivers typically cannot drive a point into a frame so that substantially all of the exposed point is in close proximity to or contiguous with the outermost panel of display materials. To make the point contiguous with prior art drivers, the operator often must bend the point into contact with the outermost panel. 
     Another advantage of the present invention point driver is that it can be used to drive both rigid points and flexible points. Prior art drivers operable with flexible points typically support the flexible point via a wall on both sides of a channel through which the point travels to prevent the point from buckling. In such devices, the point is separated from the outermost panel of the display materials by the thickness of the wall. The open channel segment of the present driver, in contrast, provides support that inhibits buckling, yet enables flexible points to be driven into a frame in close proximity to or contiguous with the outermost panel of the display materials. 
     These and other objects, features, and advantages of the present invention will become apparent in light of the detailed description of the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic cutaway view of a powered embodiment of the present invention point driver, showing the point driver in a non-actuated position. 
     FIG. 2 is a diagrammatic cutaway view of a powered embodiment of the present invention point driver, showing the point driver in an actuated position. 
     FIG. 3 is a enlarged partial view of the head shown in FIG.  1 . 
     FIG. 4 is an enlarged partial view of the head shown in FIG.  2 . 
     FIG. 5 is a diagrammatic cross-sectional view of a magazine channel and a point. 
     FIG. 6 is a diagrammatic side view of a base embodiment attachable to the point driver. 
     FIG. 7 is a diagrammatic planar view of the base shown in FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1 and 2, the point driver  10  includes a body  12 , an actuator  14 , a pushplate  16 , and a head  18 . The body  12  includes a handle  20 , a trigger  22 , and preferably a magazine  24  for holding points. The magazine  24  includes a channel  26  for receiving a stack of points  28 , a chamber end  30 , and a loading end  32 . The magazine  24  further includes a biasing mechanism  34  for biasing the stack of points  28  within the magazine  24  toward the chamber end  30 . The channel  26  has a cross-sectional geometry chosen to accept the shape of the points  28 . In some embodiments, the channel  26  cross-sectional geometry (see FIG. 5) may be asymmetrical to ensure the points  28  can only be loaded in a particular predetermined orientation. In some embodiments, the body  12  includes a contact surface  36  disposed adjacent the head  18 . 
     The actuator  14  provides sufficient force and stroke to drive the point  28  from the point driver  10  and into the frame  38  an acceptable amount of penetration. The mechanism used by the actuator  14  to create the sufficient force and stroke can be varied to suit the application. In the embodiment shown in FIGS. 1 and 2, for example, the actuator  14  includes a pneumatically operated cylinder  40  having an axial centerline  42  and a piston  44 . The actuator  14  is selectively operated by pressing the trigger  22 , which operates a valve arrangement (not shown), connected to the pneumatic cylinder  40 . Valve arrangements capable of functionally connecting the trigger  22  and the pneumatic cylinder  40  are well known in the art and therefore will not be further discussed. In other embodiments, the actuator  14  may be electrically, electromagnetically, or hydraulically powered, or may be a mechanically operated type device, or some combination thereof. 
     The pushplate  16  is a strip-like member that extends along a length  46 , a thickness  48 , and a width perpendicular to the length  46  and thickness  48 . The pushplate  16  embodiment shown in FIGS. 1-4 has a rectangular-shaped widthwise-extending cross-section. Other cross-sectional shapes may be used alternatively. The pushplate  16  extends lengthwise between a first end  50  and a second end  52 . The second end  52  of the pushplate  16  is attached to the piston  44  of the actuator  14 . In some embodiments, the pushplate  16  is attached to the piston  44  of the actuator  14  at a position offset from the axial centerline  42  of the actuator  14 . FIGS. 1 and 2, illustrate a pushplate  16  attached to the piston  44  at a position offset by an amount “X” from the axial centerline  42 . The pushplate  16  consists of a resilient material that enables the pushplate  16  to flex during its stroke. The material of the pushplate  16  can be varied to provide whatever mechanical properties are required for an application. Consequently, the pushplate  16  is not limited to any particular material. 
     The head  18  of the point driver  10  includes a first section  54 , a second section  56 , and a channel  58  disposed therebetween. The first section  54  has a length  60  and the second section  56  has a length  62 , and the length  62  of the second section  56  is greater than the length  60  of the first section  54 . The first section  54  includes a contact surface  64  that terminates at one lengthwise end  66  of the first section  54 . Contact surface  64  is preferably, but not necessarily, co-planar with contact surface  36 . The second section  56  includes an aperture  68  for receiving one or more points  28  disposed within the magazine  24 . The aperture  68  extends through the second section  56  and connects with the channel  58 . In the embodiment shown in FIGS. 1-4, a surface  70  of the second section  56 , disposed adjacent a lengthwise end  72  of the second section  56 , is spaced apart from the plane of the contact surface  64  by a distance  74  (see FIG. 3) approximately equal to the thickness of a point  28 . The head  18  is connected to the body  12  adjacent the actuator  14 . The magazine  24  is connected to the second section  56  of the head  18 , aligned with the aperture  68 . 
     Referring to FIGS. 3 and 4, the channel  58  disposed between the first section  54  and second section  56  includes a guide segment  76 , a first segment  78 , a second segment  80 , and a third segment  82  consecutively positioned; e.g., the guide segment  76  before the first segment  78 , the first segment  78  before the second segment  80 , etc. The channel further includes a centerline  83 . The guide segment  76  is disposed adjacent the actuator  14 . In the embodiment shown in FIGS. 1 and 2, the pushplate  16  is received within the guide segment  76  in both the non-actuated position (FIG. 1) and the actuated position (FIG.  2 ). In alternative embodiments, the guide segment  76  can have a convergent shape that facilitates guiding the pushplate  16  into the first segment  78  of the channel  58 . The first segment  78  is aligned with the aperture  68  disposed in the second section  56  of the head  18 , and is sized to receive a point  28  from the magazine  24 . The second segment  80  is at least partially arcuately shaped. FIGS. 3 and 4 show a portion of the second segment  80  as having a radius “R” for illustrative purposes. The arcuate shape is not, however, limited to a single radius “R”. The third segment  82  is open on the side opposite the second section  56  of the head  18 . The length  84  of the open third channel segment  82  is chosen to accommodate the length of the point  28  and the anticipated hardness of the frame  38  material, to insure that the point  28  has exited the closed segments of the channel  58 . The guide segment  76 , first segment  78 , and second segment  80 , and in some embodiments the third segment  82 , are shaped to receive and guide the pushplate  16 . The first through third channel segments  78 , 80 , 82  are also shaped to receive and guide points  28 . 
     In the guide segment  76  and first segment  78  of the channel  58 , the centerline  83  of the channel  58  is substantially straight, extending at a mat angle “φ” from the plane of the contact surface  64 . The arcuate portion of the second segment  78  decreases the magnitude of the mat angle “φ” between the centerline  83  of the channel and the plane of the contact surface  64  from “φ 1 ” to “φ 2 ”, wherein “φ 2 ” is less than “φ 1 ”. The third segment  82  is an open portion of the channel  58  that is bounded on one side by the second section  56  of the head  18 . The first section  54  of the head  18  terminates at the beginning of the third segment  82 . The centerline  83  of the channel  58  within the third segment  82  can be arcuate or straight, or some combination thereof. 
     Referring to FIGS. 6 and 7, some embodiments of the point driver  10  further include a base  92  to increase the stability of the point driver  10 . The base  92  has a top surface  94  and a contact surface  96 . The top surface  94  is contoured to receive a portion of the actuator  14 . An aperture  98  is disposed in the contact surface  96  to receive the contact surface  36  of the body  12 . The contact surface  96  of the base  92  is oriented such that it is substantially coplanar with the contact surface  36  of the body  12  when the base  92  is mounted on the body  12 . A fastener  100  (see FIGS. 1 and 2) is used to attach the base  92  to the point driver  10 . In an alternative embodiment, the base  92  can be integrally formed with the body  12 . 
     Referring to FIGS. 1-4, in the operation of the point driver  10  a plurality of points  28  are loaded into the magazine  24 . As stated above, the present invention point driver  10  can be used with a variety of different shaped points  28  and is, therefore, not limited to use with any particular point  28 . In certain applications, however, the magazine  24  can be asymmetrically configured to require points  28  be loaded in a particular orientation (see FIG.  5 ). 
     The pushplate  16  is positionable in a non-actuated position as is shown in FIG.  1 . In this position, the piston  44  is located adjacent a first end  88  of the actuator  14 , and the pushplate  16  is disposed adjacent to or within the guide segment  76  of the channel  58 . With the pushplate  16  in this position, a point  28  is disposed in the channel  58 . The biasing mechanism  34  biases the stack of points  28  within the magazine  24 , thereby causing one of the points  28  to pass through the aperture  68  in the second section  56  of the head  18  and into the first segment  78  of the channel  58 . In an embodiment that does not include a magazine  24 , a point  28  could also be manually loaded within the first segment  78  of the channel  58 . 
     Pressing the trigger  22  causes the piston  44  within the actuator  14 , and therefore the attached pushplate  16 , to be driven axially toward the head  18 . Within the first segment  78  of the channel  58 , the first end  50  of the pushplate  16  contacts the point  28  disposed within the first segment  78  and drives it into the second segment  80 . Within the second segment  80  of the channel  58 , the resilient pushplate  16  and the point  28  travel through the arcuate portion and thereby change the mat angle at which they are approaching the frame  38  from “φ 1 ” to “φ 2 ”, wherein “φ 2 ” is less than “φ 1 ”. The resilient material of the pushplate  16  that gives it flexibility enables the pushplate  16  to travel initially through the straight guide segment  76  and first segment  78 , and subsequently through the arcuate second segment  80  without binding. The point  28  subsequently exits the second channel segment  80 , passes through the third segment  82 , and penetrates the frame  38 . The open structure of the third channel segment  82  enables the point  28  to move toward the outermost display panel  90 . The surface  70  of the second section  56 , disposed adjacent the lengthwise end  72  of the second section  56 , advantageously further guides the point  28  to a position that is substantially contiguous and parallel with the outermost panel  90 . In some instances, the point  28  may partially intersect with the outermost panel  90 . 
     As described above, the pushplate  16  travels through the entire first and second channel segments  78 , 80 . In alternative embodiments, the stroke of the pushplate  16  can be greater or lesser than that shown in FIGS. 1-4. 
     Once the actuator  14 , and therefore the attached pushplate  16 , has reached the end of its stroke, the actuator  14  retracts the piston  44  and pushplate  16  back to the non-actuated position. Once the pushplate  16  has retracted beyond the first segment  78 , the biasing mechanism  34  automatically reloads the point driver  10  by biasing another point  28  into the channel  58 . 
     Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail thereof may be made without departing from the spirit and scope of the invention. For example, the present invention has been described above for use with framer&#39;s points  28 . The present invention may also be used with other fasteners.