Patent Description:
There are various fastener drivers known in the art for driving fasteners (e.g., nails, tacks, staples, etc.) into a workpiece. These fastener drivers operate utilizing various means known in the art (e.g., compressed air generated by an air compressor, electrical energy, a flywheel mechanism, etc.) to drive a driver blade from a top-dead-center position to a bottom-dead-center position.

According to its opening statement, <CIT> describes pneumatic devices, and more particularly a unique air gun mechanism for driving corrugated nails. This document discloses the preamble of claim <NUM>.

According to its abstract, <CIT> describes a driver blade for use in a fastening tool having a piston comprising an elongate body, a head at one end of the body for coupling to the piston, a tip at the other end of the body for impacting a fastener to drive said fastener into a workpiece, and a stiffening rib protruding from the body, the rib extending substantially along the length of the body, wherein the stamped elongate driver blade is made of annealed cold rolled spring steel. A novel method of manufacturing an elongate driver blade is also provided comprising the steps of providing cold rolled spring steel, forming an elongate blank from the cold rolled spring steel, providing a stamping die having a generally planar stamping surface with an elongate groove in the stamping surface, and stamping the blank into the stamping die with the elongate groove to form the elongate driver blade having an elongate stiffening rib.

Aspects of the present invention are defined by the appended independent claim.

Other features and aspects will become apparent by consideration of the following detailed description and accompanying drawings. Any feature(s) described herein in relation to one aspect or embodiment may be combined with any other feature(s) described herein in relation to any other aspect or embodiment as appropriate and applicable.

Before any embodiments are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments.

With reference to <FIG>, a gas spring-powered fastener driver <NUM> is operable to drive fasteners (e.g., nails, tacks, staples, etc.) held within a magazine <NUM> into a workpiece. The fastener driver <NUM> includes a cylinder <NUM>. A moveable piston (not shown) is positioned within the cylinder <NUM>. With reference to <FIG>, the fastener driver <NUM> further includes a driver blade <NUM> that is attached to the piston and moveable therewith. The fastener driver <NUM> does not require an external source of air pressure, but rather includes pressurized gas in the cylinder <NUM>.

With reference to <FIG>, the fastener driver <NUM> includes a housing <NUM> having a cylinder housing portion <NUM> and a motor housing portion <NUM> extending therefrom. The cylinder housing portion <NUM> is configured to support the cylinder <NUM>, whereas the motor housing portion <NUM> is configured to support a motor <NUM> and a transmission <NUM> downstream of the motor <NUM>. In addition, the illustrated housing <NUM> includes a handle portion <NUM> extending from the cylinder housing portion <NUM>, and a battery attachment portion <NUM> coupled to an opposite end of the handle portion <NUM>. A battery (not shown) is electrically connectable to the motor <NUM> for supplying electrical power to the motor <NUM>. The handle portion <NUM> supports a trigger (not shown), which is depressed by a user to initiate a driving cycle of the fastener driver <NUM>.

With reference to <FIG>, the driver blade <NUM> defines a longitudinal axis <NUM>. During a driving cycle, the driver blade <NUM> and piston are moveable between a top-dead-center (TDC) or ready position within the cylinder <NUM>, and a bottom-dead-center (BDC) or driven position, along the axis <NUM>. The fastener driver <NUM> further includes a lifter assembly (not shown), which is powered by the motor <NUM> (<FIG>), and which is operable to return the driver blade <NUM> from the driven position to the ready position.

The fastener driver <NUM> further includes a nosepiece assembly <NUM> that receives collated fasteners from the magazine <NUM> (<FIG> and <FIG>). The nosepiece assembly <NUM> includes a nosepiece <NUM> and a shear block <NUM> that collectively define a fastener driving channel or track <NUM> (<FIG>, and <FIG>) that guides the fasteners as they are driven into a workpiece by the driver blade <NUM>. The shear block <NUM> further defines an opening (not shown) that permits fasteners to pass from the magazine <NUM> through the shear block <NUM> and into the driver track <NUM>.

With reference to <FIG>, and <FIG>, the driver blade <NUM> includes an elongated body <NUM> having a first planar surface (i.e., a front surface <NUM>) and an opposite, a second planar surface (i.e., a rear surface <NUM>). A first edge <NUM> extends between the front surface <NUM> and the rear surface <NUM> along one lateral side of the body <NUM>, and a second edge <NUM> extends between the front surface <NUM> and the rear surface <NUM> along an opposite lateral side of the body <NUM>. The front surface <NUM> is parallel to the rear surface <NUM>. Likewise, the edges <NUM>, <NUM> are also parallel.

The driver blade <NUM> includes a plurality of lift teeth <NUM> formed along the first edge <NUM> of the body <NUM>. The first edge <NUM> extends in the direction of the axis <NUM>, and the lift teeth <NUM> project from the first edge <NUM> in a direction transverse to the axis <NUM>. The lift teeth <NUM> are sequentially engaged with the lifter assembly during the return of the driver blade <NUM> from the driven position to the ready position. In addition, the driver blade <NUM> includes a plurality of projections <NUM> extending from the second edge in a direction transverse to the axis <NUM>. In one embodiment, the plurality of projections <NUM> are configured to engage a latch (not shown) of the fastener driver <NUM> for inhibiting the driver blade <NUM> from moving toward the driven position.

The driver blade <NUM> further includes a first end 22a and a second end, or distal end 22b opposite the first end 22a. The front and rear surfaces <NUM>, <NUM>, and the first and second edges <NUM>, <NUM>, extend between the first and second ends 22a, 22b. In the illustrated embodiment of the driver blade <NUM>, the first end 22a includes an aperture <NUM> for receiving a fastener (e.g., screw, bolt, etc.) for connection with the piston. The second end 22b of the driver blade <NUM> is oriented perpendicular to the axis <NUM> for striking fasteners fed from the magazine <NUM> and driving the fasteners into a workpiece. The driver blade <NUM> additionally includes an elongated recess <NUM> extending along the front surface <NUM> (i.e., the surface facing the nosepiece <NUM>) of the driver blade <NUM>, the purpose of which is described below.

With reference to <FIG>, the driver blade <NUM> includes a guiding projection <NUM> positioned on the elongated body <NUM>. The guiding projection <NUM> is parallel with the longitudinal axis <NUM> of the driver blade <NUM> and also extends in a direction that is transverse to the axis <NUM> to be received within a corresponding recess <NUM> (<FIG>, <FIG>, <FIG>, and <FIG>) within the nosepiece <NUM> to provide lateral stability to the driver blade <NUM> as it reciprocates between its ready and driven positions. The guiding projection <NUM> is located near the second end 22b of the driver blade <NUM> and terminates before the distal end 22b of the driver blade <NUM>, creating a gap <NUM> between the guiding projection <NUM> and the distal end 22b (<FIG>). This allows for the driver blade <NUM> to be guided within the nosepiece <NUM>, but also prevents the projection <NUM> from contacting the work surface with the driver blade <NUM>. As such, the guiding projection <NUM> does not cause a "mar" or "indentation" on the work surface as a fastener (i.e., staple <NUM>) is driven into the surface.

The nosepiece <NUM> includes an elongated body <NUM> having a first planar surface, or front surface <NUM> and an opposite, second planar surface, or rear surface <NUM>, such that the front surface <NUM> is parallel to the rear surface <NUM>. The nosepiece <NUM> further includes an elongated guide groove <NUM> within the rear surface <NUM> extending parallel with the axis <NUM> that partially defines the fastener driver track <NUM> (<FIG>). The guide groove <NUM> is sized to receive the width of the driver blade <NUM> (below the last of the teeth <NUM> and projections <NUM>) and the staples <NUM> to provide lateral stability to the staples <NUM> as they are driven from the nosepiece assembly <NUM> (<FIG>). The recess <NUM> in which the guiding projection <NUM> is received is also located in the guide groove <NUM>.

With reference to <FIG>, and <FIG>, the nosepiece <NUM> includes guide ribs <NUM> extending along the rear surface <NUM> of the nosepiece <NUM>, such that the ribs <NUM> are substantially parallel to each other. The space between the ribs <NUM><NUM>+ defines an extension of the guide groove <NUM> and provides additional lateral support for the staples <NUM> during a firing operation. Specifically, when in the fastener driver track <NUM>, an upper portion 102a of the staple <NUM> is supported by the guide ribs <NUM> and a lower portion 102b of the staple <NUM> is supported within the guide groove <NUM>. The nosepiece <NUM> additionally includes laterally extending ribs <NUM> connecting opposite sides of the nosepiece <NUM> with the respective ribs <NUM>. The laterally extending ribs <NUM> are oriented perpendicular relative to the guide ribs <NUM>. In alternative embodiments (<FIG>), the laterally extending ribs <NUM> may be omitted.

More specifically, and with reference to the illustrated embodiment of the fastener driver <NUM> of <FIG>, the staple <NUM> includes a length L1 of approximately <NUM>. The guide ribs <NUM> include a length L2 of <NUM> and the guide groove <NUM> includes a length L3 of <NUM>. Furthermore, a distance D1 from a crown of the staple <NUM> to a distal end of the guide rib <NUM> is approximately <NUM>. When the staple <NUM> is loaded from the magazine <NUM> into the fastener driving track <NUM>, the guide ribs <NUM> support approximately <NUM>, or <NUM>%, of the length of the staple <NUM> (coinciding with length L2). Additionally, the guide groove <NUM> supports approximately <NUM>, or <NUM>%, of the length L1 of the staple <NUM> (coinciding with length L3). As such, in total, approximately <NUM>, or <NUM>%, of the length L1 of the staple <NUM> is supported by a combination of the guide ribs <NUM> and the guide groove <NUM>, leaving the remaining <NUM>% of the length L1 of the staple <NUM> unsupported and extending beyond the distal ends of the guide ribs <NUM> (coinciding with distance D <NUM>).

<FIG> illustrate an alternative embodiment of a fastener driver <NUM>', with like parts as the fastener driver <NUM> of <FIG> being shown with like reference numerals plus a prime marker (').

The fastener driver <NUM>' includes a driver blade <NUM>' that is attached to a piston and moveable therewith. The fastener driver <NUM>' further includes a nosepiece assembly <NUM>' including a nosepiece <NUM>' and a shear block (not shown, similar to the shear block <NUM> shown in <FIG>) that collectively define a fastener driving channel or track <NUM>' (<FIG>) that guides fasteners as they are driven into a workpiece by the driver blade <NUM>'.

With reference to <FIG>, the driver blade <NUM>' includes an elongated recess <NUM>' extending along a front surface <NUM>' (i.e., the surface facing the nosepiece <NUM>') of the driver blade <NUM>'. The elongated recess <NUM>' includes a portion <NUM>' having a greater width than the rest of the recess <NUM>', the purpose of which is described below.

With reference to <FIG>, the nosepiece <NUM>' includes a guide groove <NUM>' sized to receive the width of the driver blade <NUM>' (below the last of teeth <NUM>' and projections <NUM>' of the driver blade <NUM>') and staples <NUM>' to provide lateral stability to the staples <NUM>' as they are driven from the nosepiece assembly <NUM>'. The nosepiece <NUM>' additionally includes guide ribs <NUM>' extending along a rear surface <NUM>' of the nosepiece <NUM>', such that the ribs <NUM>' are substantially parallel to each other. The space between the ribs <NUM>' defines an extension of the guide groove <NUM>' and provides additional lateral support for the staples <NUM>' during a firing operation.

More specifically, and with reference to the illustrated embodiment of the fastener driver <NUM>' of <FIG>, the staple <NUM>' includes a length L1' of approximately <NUM>. The guide ribs <NUM>' include a length L2' of <NUM> and the guide groove <NUM>' includes a length L3' of <NUM>. Furthermore, a distance D1' from a crown of the staple <NUM>' to a distal end of the guide rib <NUM>' is approximately <NUM>. When the staple <NUM>' is loaded into the fastener driving track <NUM>', the guide ribs <NUM>' support approximately <NUM>, or <NUM>%, of the length of the staple <NUM>'. Additionally, the guide groove <NUM>' supports approximately <NUM>, or <NUM>%, of the length L1' of the staple <NUM>'. As such, in total, approximately <NUM>, or <NUM>%, of the length L1' of the staple <NUM>' is supported by a combination of the guide ribs <NUM>' and the guide groove <NUM>', leaving the remaining <NUM>% of the length L1' of the staple <NUM>' unsupported and extending beyond the distal ends of the guide ribs <NUM>'.

As the driver blade <NUM>' moves from the ready position to the driven position (with the driven position being shown in <FIG>), the guide ribs <NUM>' of the nosepiece <NUM>' slide within the enlarged portion <NUM>' of the elongated recess <NUM>' in the driver blade <NUM>' (<FIG> and <FIG>). Because the driver blade <NUM>' overlaps the guide ribs <NUM>' in this manner, the overall height of the fastener driver <NUM>' is reduced, compared to a prior art fastener driver in which the majority of the length of the fasteners is supported within the guide groove <NUM>'. In some embodiments of the fastener driver <NUM>', the ratio of a length L4' from the crown of the staple <NUM>' to a distal end of the nosepiece <NUM>' (<FIG>) to a total length L5' of the tool <NUM>' (<FIG>) is less than <NUM>%. In the illustrated embodiment of the fastener driver <NUM>', the length L4' is <NUM> (<FIG>), and the total length L5' of the tool <NUM>' is <NUM> (<FIG>). As such, the ratio of L4':L5' is approximately <NUM>%.

Claim 1:
A fastener driver (<NUM>) comprising:
a housing (<NUM>);
a cylinder (<NUM>) disposed within the housing;
a piston positioned and moveable within the cylinder;
a nosepiece (<NUM>) at least partially defining a fastener driving track (<NUM>) through which fasteners are driven; and
a driver blade (<NUM>) attached to the piston and moveable with the piston to drive the fasteners through the fastener driving track, the driver blade including an elongated body (<NUM>) having a first edge (<NUM>) extending between a front surface and a rear surface along one lateral side of the body;
wherein the driver blade includes an axial guiding projection (<NUM>) for guiding the driver blade within the nosepiece, and wherein the projection terminates before a distal end (22b) of the driver blade,
wherein the nosepiece includes a recess (<NUM>) extending along a length of the nosepiece, and wherein the recess is configured to receive the axial guiding projection,
wherein the nosepiece includes a longitudinal guide groove (<NUM>) in which the fasteners are received, and wherein the longitudinal guide groove at least partially defines the fastener driving track, and
characterised in that it further comprises a plurality of lift teeth (<NUM>) formed along the first edge of the body (<NUM>), wherein the lift teeth (<NUM>) are sequentially engaged with a lifter assembly during return of the driver blade (<NUM>) from a driven position to a ready position;
wherein the nosepiece includes parallel guide ribs (<NUM>) extending from an interior surface of the nosepiece, thereby defining an extension of the guide groove.