Nailer for hardwood flooring

A nailer is provided for securing planks to a subfloor in tight places with fasteners. A fastener ejection channel made in the nailer is formed in between a pair of first and second guide plates spacedly mounted parallel to one another. The first guide plate defines a planar inner end portion having an ovoidal slot and an outer end portion defining a transverse arcuate first flange. The second guide plate defines an arcuate second flange extending away from the first guide plate and generally parallel to the first flange. An elongated straight push rod is mounted partially nested at an inner end in the ovoidal slot. The bottom portion of the push rod is movable along the fastener ejection channel between first and second limit positions. A lengthwise notch extends along the second guide plate intermediate section and opens into the second flange and is sized and shaped to accommodate transverse passage of an outer end portion of the push rod, wherein the push rod moves rectilinearly between the first and an intermediate position thereof but the push rod outer end portion tilts laterally away from the first guide plate when moving in non-rectilinear fashion between the intermediate and second limit positions thereof.

FIELD OF THE INVENTION

The present invention relates to fastener driving tools, and more particularly to a nailing device for driving fasteners through hardwood planks in tight corners in order to secure them to a subfloor.

BACKGROUND OF THE INVENTION

Hardwood flooring generally consists of a number of elongated tongue-and-groove type planks individually fitted close to one another and then fastened in position to a subjacent subfloor. To fasten these hardwood planks to the subfloor of a room composed for example of plywood plates or floor joists, it is known to manually use a mallet-operated nailer. Such a nailer generally comprises a main body with a floor-engageable flat shoe mounted to its bottom surface, upon which the tool rests against a hardwood plank prior to discharging a fastener in the latter. Such a nailer also comprises a magazine holding fasteners such as straight metallic L- or T-shaped barbed straight cleats or U-shaped straight staples, and feeding them to a fastener discharge mechanism. With such manual nailers, to fasten a hardwood plank to the subfloor, a workman has to lay the nailer onto a hardwood plank, and then use a mallet to strike an anvil member of the fastener discharge mechanism. When a mallet strikes the anvil member of the tool, a straight and elongated plunger of the fastener discharge mechanism is axially actuated to strike a cleat held in the magazine, this cleat being then forcibly ejected out of the tool.

In order to hide the nail heads, some nailers drive the fasteners through the plank and into the subfloor in an oblique direction, as opposed to being driven in the planks vertically. This is called “blind nailing”.

However, known nailers driving fasteners in an oblique fashion in hardwood planks reach with difficulty areas very close to upright walls. The hardwood planks located parallel to an upright wall in closely spaced fashion cannot be anchored to the subfloor using such nailers, and the fasteners must instead be driven vertically, e.g. using a manual hammer and nail, into the hardwood plank edge portions adjacent to walls.

The invention described in applicant's U.S. Pat. No. 7,303,105 issued Dec. 4, 2007 relates to a nailer for hardwood flooring capable of working directly against an upright wall, but is limited to fasteners being originally arcuate in shape to start with. One drawback of this prior art patent was complexity of its operating mechanism.

A problem with conventional pneumatic nailers is that their nail driver rod must necessarily follow an axially aligned travel path for 100% of their travelling direction, due to the limitation of the straight nailer guide plates. This is a drawback when using straight nails with a nailer, very close to or against an upright wall or other obstacle over the work surface.

SUMMARY OF THE INVENTION

In one embodiment of the invention, a nailer is provided for securing planks to a subfloor or other structure in tight places using fasteners, said nailer comprising: a main body defining a fastener discharge mouth; fastener ejection means operatively mounted in said nailer main body for accommodating passage of a fastener, the fastener having a head at one end and an opposite tip, said fastener ejection means opening outwardly of said nailer at said fastener discharge mouth; an elongated straight push rod, defining an inner end thereof operatively mounted to said fastener ejection means, and defining an outer end portion thereof for freely axially engaging the fastener head, said push rod movable between first and second limit positions, including an intermediate position between said first and second limit positions; wherein said push rod moves rectilinearly between said first and intermediate positions thereof but said push rod outer end portion tilts laterally away when moving in a non-rectilinear fashion between said intermediate and second limit positions thereof; and a plunger actuator nested in said main body and operatively connected to said inner end portion of said push rod, wherein said plunger actuator can be selectively activated for moving said push rod between its said first and second limit positions; wherein upon activation of said plunger actuator, said push rod will move along said fastener ejection means from said first limit position towards said second limit position to forcibly strike the fastener head, wherein between said intermediate position and said second limit position, the push rod outer end portion will be ejected out of said nailer through said fastener discharge mouth and into a subjacent workpiece.

In one embodiment, said fastener ejection means could consist of a fastener ejection channel made in said nailer main body, said fastener ejection channel being formed in between a pair of first and second registering guide plates spacedly mounted parallel to one another for accommodating therebetween passage of a fastener, said first guide plate defining a planar first intermediate section and a planar inner end portion having a lengthwise slider mounting means and an outer end portion defining an arcuate first flange crossing the plane of said first intermediate section, said second guide plate defining a planar second intermediate section having an outer end portion defining an arcuate second flange crossing the plane of said first main body away from said first guide plate and generally parallel to said first flange; said elongated straight push rod, partially nested at an inner end thereof in said fastener ejection channel slider mounting means, said push rod movable along said fastener ejection channel between first and second limit positions; a lengthwise notch further extending along said second guide plate intermediate section and opening into said second flange and sized and shaped to accommodate transverse passage of said outer end portion of said push rod, wherein said push rod outer end portion tilts laterally away from said first guide plate when moving in said non-rectilinear fashion between said intermediate and second limit positions thereof; wherein upon activation of said plunger actuator, the push rod outer end portion will become laterally dynamically deflected by said first flange transversely of the plane of said first guide plate intermediate section and will move through said second guide plate notch and biasing the fastener to escape through said fastener discharge mouth to be ejected out of said nailer through said fastener discharge mouth and into a subjacent workpiece. Said slider mounting means could then define an ovoidal slot made into said first intermediate section of said first guide plate, and a slider carriage operatively slidingly mounting said push rod inner end for relative movement to said ovoidal slot.

In another embodiment of the invention, there is disclosed a nailer for securing planks to a subfloor or other structure in tight places using fasteners, said nailer comprising: a main body defining a fastener discharge mouth; a fastener ejection channel made in said nailer main body, said fastener ejection channel being formed in between a pair of first and second registering guide plates spacedly mounted parallel to one another for accommodating therebetween passage of a fastener, the fastener having a head at one end and an opposite tip, said fastener ejection channel opening outwardly of said nailer at said fastener discharge mouth, said first guide plate defining a planar first intermediate section and a planar inner end portion having a lengthwise slider mounting means and an outer end portion defining an arcuate first flange crossing the plane of said first intermediate section, said second guide plate defining a planar second intermediate section having an outer end portion defining an arcuate second flange crossing the plane of said first main body away from said first guide plate and generally parallel to said first flange; fastener push means, for freely axially engaging the fastener head, and a plunger actuator nested in said main body and operatively connected to said fastener push means; wherein upon activation of said plunger actuator, said fastener push means will bias the fastener to escape through said fastener discharge mouth to be ejected out of said nailer through said fastener discharge mouth and into a subjacent workpiece.

In this latter embodiment, said fastener push means could then consist of an elongated straight push rod, partially nested at an inner end thereof in said fastener ejection channel slider mounting means, and defining an outer end portion thereof for freely axially engaging the fastener head, said push rod movable along said fastener ejection channel between first and second limit positions, including an intermediate position between said first and second limit positions; a lengthwise notch further extending along said second guide plate intermediate section and opening into said second flange and sized and shaped to accommodate transverse passage of said outer end portion of said push rod, wherein said push rod moves rectilinearly between said first and intermediate positions thereof but said push rod outer end portion tilts laterally away from said first guide plate when moving in non-rectilinear fashion between said intermediate and second limit positions thereof; said plunger actuator nested in said main body being operatively connected to said inner end portion of said push rod, wherein said plunger can be selectively activated for moving said push rod between its said first and second limit positions; wherein upon activation of said plunger actuator, said push rod will move along said fastener ejection channel from said first limit position towards said second limit position to forcibly strike the fastener head, wherein between said intermediate position and said second limit position, the push rod outer end portion will become laterally dynamically deflected by said first flange transversely of the plane of said first guide plate intermediate section and will move through said second guide plate notch and biasing the fastener to escape through said fastener discharge mouth to be ejected out of said nailer through said fastener discharge mouth and into a subjacent workpiece. Said slider mounting means could then define an ovoidal slot made into said first intermediate section of said first guide plate, and a slider carriage operatively slidingly mounting said push rod inner end for relative movement to said ovoidal slot.

In still another embodiment of the invention, there is disclosed use of a nailer for securing hardwood flooring planks to a subfloor in tight places using fasteners, said nailer comprising: a main body defining a fastener discharge mouth; a fastener ejection channel made in said nailer main body, said fastener ejection channel being formed in between a pair of first and second registering guide plates spacedly mounted parallel to one another for accommodating therebetween passage of a fastener, the fastener having a head at one end and an opposite tip, said fastener ejection channel opening outwardly of said nailer at said fastener discharge mouth, said first guide plate defining a planar first intermediate section and a planar inner end portion having a lengthwise slider mounting means and an outer end portion defining an arcuate first flange crossing the plane of said first intermediate section, said second guide plate defining a planar second intermediate section having an outer end portion defining an arcuate second flange crossing the plane of said first main body away from said first guide plate and generally parallel to said first flange; an elongated straight push rod, partially nested at an inner end thereof in said fastener ejection channel slider mounting means, and defining an outer end portion thereof for freely axially engaging the fastener head, said push rod movable along said fastener ejection channel between first and second limit positions, including an intermediate position between said first and second limit positions; a lengthwise notch further extending along said second guide plate intermediate section and opening into said second flange and sized and shaped to accommodate transverse passage of said outer end portion of said push rod, wherein said push rod moves rectilinearly between said first and intermediate positions thereof but said push rod outer end portion tilts laterally away from said first guide plate when moving in non-rectilinear fashion between said intermediate and second limit positions thereof; and a plunger actuator nested in said main body and operatively connected to said inner end portion of said push rod and movable along an axial channel defining a direction of displacement thereof, wherein upon actuation of said plunger actuator, said plunger actuator moves said push rod between its said first and second limit positions and said push rod forcibly strikes the fastener head, wherein between said intermediate position and said second limit position, the push rod outer end portion becomes laterally dynamically deflected by said first flange transversely of the plane of said first guide plate intermediate section and moves through said second guide plate notch and biases the fastener to escape through said fastener discharge mouth to be ejected out of said nailer through said fastener discharge mouth and into a subjacent workpiece.

In this latter embodiment, said fastener could be ejected through said fastener ejection channel in a direction diverging from said axial channel direction of displacement of said plunger actuator.

One general feature of the present invention is the simplicity in the manufacturing process of the nailer.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 14shows one example of a nail,20, for use in manually mallet operated type nailers, and which is used with the nailer of the present invention. In front elevation, nail20has an elongated body22which tapers to a pointed tip portion24, and has a flat head26at an elbowed end portion of the nail body22, opposite the pointed tip portion24. Elbowed head26must be preferably perpendicular to the elongated body22, for best performance. More particularly, nail20is elbowed at its upper end portion to form the perpendicularly extending flat head26, nail20thus generally being for example L-shaped. Nail20has a generally flat body22, and is transversely much thinner in edge view, than in the front elevation.

A number of nails20can be serially linked by flatly successively abutting the nails on their flat surfaces and attaching them by means of known frangible joints, to form a planar nail cartridge28of known configuration. The nail cartridge made from a plurality of such L-shaped nails can be loaded into a nailer, for allowing the nails to be successively detached and used one at a time.

FIGS. 1 to 8show a nailer30according to the invention, comprising a main rigid frame body32having an upright column34, a transverse, rearwardly extending nail magazine36, and a flat shoe37affixed to the bottom thereof for sliding abutment over a wooden work surface W (FIGS. 11 and 13-14). A handle35is fixed over and outwardly of magazine36, for manually carrying nailer30spacedly over ground, and for securely holding nailer30against the surface to be nailed.

InFIG. 12, column34has a vertical chimney38therein, in which is vertically slidable a plunger actuator40carrying a downwardly-depending flat driver rod42defining a horizontally flat, lower abutment edge44. Plunger actuator40is further provided with a coil spring46which abuts and is attached at the chimney38lower end seat, spring46biasing actuator40towards an upper resting position. A guiding pole (not shown) may be provided coaxially inside coil spring46for guiding the latter, being attached at the lower end seat of chimney38, and axially engaging a complementary vertical hole extending inside actuator40. Actuator40is guided by chimney38in its downward sliding displacement. Upon hitting the upper heel48of actuator40with a hammer or other suitable device, actuator40will be suddenly forcibly downwardly displaced against the bias of spring46, but at the end of its outward motion, it will move back and it will retrieve its upper resting position under the bias of spring46after the blow has been dealt.

The front portion of nailer30comprises an elongated front plate50and a shorter rear plate52, all attached to the nailer column34by means of guiding pins and bolts55extending transversely therethrough, wherein plates50and52are in spaced register with one another. Plates50,52, form guide plates for the fasteners20. Front plate50is shaped and sized to conform to the front of body34at its narrower upper portion50A. A nail ejection channel53(FIG. 11) is formed in the gap between guide plates50and52.

Preferably, front plate50is forwardly offset relative to the lengthwise plane of actuator plunger40, to reduce the likelihood of a user accidentally striking adjacent upright wall with user's mallet. Rear plate52has a downwardly opening notch52A, sized and shaped wherein the lower portion of driver rod42is slidingly engageable therethrough. The bottom edges of guide plates50,52, each form a rearwardly downwardly inclined arcuate flange54,56, respectively, complementary to one another and a nail ejection mouth58being defined at the bottom end of notch52A between flanges54and56, through which nails are to be expelled away from nailer30. Flanges54,56, are in spaced register with one another and form together an anvil member, which will bias the nail20to tilt away from the original driving axis of drive rod42, as will be detailed hereinbelow.

Upper portion52A of front guide plate50includes an ovoidal slot60, guidingly receiving a transverse coupling element61integral to the top enlarged integral ear42A of driver rod42. Driver rod42further defines a thinner lower portion42B, between wider main portion42and enlarged bottom end portion44.

FIGS. 15 to 18sequentially show a nail being expelled out from nailer30. The frontmost nail20of the nailer magazine36is vertically supported by its frangible joint attachment to the rearwardly adjacent nail28′ (FIG. 14) of the nail cartridge28located in the magazine36.

In use, the lead nail20of the nail cartridge28is initially located and positioned as shown inFIG. 15, i.e. biased into abutment against front plate50and vertically positioned spacedly under driver rod bottom end44and spacedly over fastener ejection mouth58. Upon forcibly hitting the heel48of the plunger actuator40, driver rod42is downwardly driven and flatly impacts with its flat bottom abutment end44against the flat top head26of nail20, for downwardly driving nail20, as shown inFIGS. 16-18. Since the adjacent nail20′ to lead nail20of nail cartridge28downwardly rests with its head26on the main body of magazine36, it will not be downwardly carried with the frontmost nail20, the frangible joint between the two nails being ruptured upon impact from driver rod42on the frontmost leading nail20.

As the nail20and driver rod42move downwardly coaxially with the longitudinal axis of plunger actuator40, the nail bottom tip24will come to eventually engage with flange54. The bottom portion of nail20will thereafter become deflected laterally away from the main body of guide plate50and towards registering guide plate52. Driver rod42will move downwardly therewith, with the driver rod head42A slidingly mounted for relative movement to ovoidal slot60by connector61. As laterally deflected nail20moves further downwardly, the lower thinner recess section42B of driver rod42will also become laterally deflected and will transversely engage through registering notch52A of guide plate52to follow the offset ejected travel axis of nail20, i.e. diverging off axis relative to said longitudinal axis of plunger actuator40, while the upper larger section of driver rod42remains within said longitudinal axis of actuator40.

It is thus understood that during successive ejections of nails, plunger actuator40will remain axially aligned at all times, while driver rod42will tilt in oscillating like fashion about its lower end portion42B. That is to say, the upper end portion42A of driver rod42, being mounted for relative movement by connector mount61to the lower end of actuator40, will remain axially aligned with actuator40, while the lower end portion42B of driver rod42will swing back and forth in reciprocating fashion relative to large plate50with successive nails ejections. The change in travelling direction of the lower portion42B of driver rod42occurs only at the level of the nail ejection mouth58, not inside the inner nail ejection channel53leading to this mouth58. In other words, the travelling direction of driver rod42and associated nail20is arcuate for only a fraction of the total travel thereof; there is a first travelling segment which is axially straight, and then there is a second travelling segment which is translational (with tilting motion) but only for the lower portion thereof.

It is clearly seen in the sequence ofFIGS. 15-18that the lower end44of driver rod42constantly remains in contact with smaller guide plate52, within channel52A. In one embodiment, drive rod lower portion44remains guided by channel52A for about 80% of the travelling distance thereof, while it becomes tilted for the remainder 20% of travel thereof.

However, when drive rod lower portion44reaches the flange56of guide plate52, the recess42B of drive rod42enables the latter to clear the channel53between guide plates50,52, and to transversely engage into guide plate notch52A.

It is noted that no spring biasing means is required for enabling and sustaining swinging motion of the lower portion of drive rod42.

As suggested inFIGS. 13 and 14, arcuate deformation of the originally straight nail20into a curved nail120may occur, under buckling forces. These buckling forces may be independent of resistance loads from the underlying wooden work surface, i.e. transverse loads born solely by the nail20engaging bottom flanges54,56of lower guide plates50,52, are sufficient to curve the originally straight nail.

FIG. 14suggests how the nailer30can be operated with its front end50abutting directly against an upright wall U, with the leading nail120having been deflected rearwardly downwardly away from the plane of upright wall U into the underlying wooden work surface W. This way, the curved ejected nail120will become engaged into a work surface portion spacedly away from the more brittle edge portion We thereof in register with the upright wall U.

It is understood that the nailer30of the present invention has been described for nailing floor boards to a subfloor, but it could be used to nail any suitable wall surface. The present nailer30is particularly efficient in getting very close to or directly against an upright obstacle, without compromising nailing efficiency for a subjacent work piece.

Also, the nailer30has been shown with a nail-driving anvil member or plunger actuator40, although it is understood that the driver rod42could be propelled with any selectively actuated power means, such as a hydraulic power device, for example.

The nailer head or heel portion48also may comprise a ring having a larger diameter than plunger actuator40, this ring coming into downward vertical abutment with the upper surface of the upright column of nailer30, to limit actuator40to a downward limit position.

Any other modifications, which do not deviate from the scope of the present invention, are considered to be included therein. For example, in one embodiment, the manual plunger actuator40could be replaced by the main piston shaft of a pneumatic type nailer.