1. Field of the Invention
The present invention is generally related to fastener driving devices, and more particularly to a contact trip foot for fastener driving devices.
2. Description of Related Art
Typical pneumatic fastener driving tool actuation is achieved via the displacement of a “contact arm,” or “contact trip” through contact with a work surface, in combination with a user/operator “trigger.” The contact arm is typically constructed of stamped steel or formed wire, thereby producing an otherwise resilient member allowed to travel axially with the intended fastener driving direction, and generally adjacent to or in proximity of a “nose” of the tool through which the fastener is driven. A molded rubber covering called a “trip foot” is frequently affixed to the contact arm. The trip foot is usually removable and is intended to protect softer substrates from developing depressions as a result of direct contact with the relatively hard contact arm. The nose is typically of a geometry that forms a complete or nearly complete channel through which a fastener is guided by nature of the restrictive walls of the channel. While the channel walls provide guidance of the fastener, they also tend to obscure from view of the operator the exact location of the fastener upon exiting the nose. Further, the proximity of the contact arm to the nail exit region of the nose often contributes to this obscurity. Additionally, the trip foot may obscure the view even more.
In many applications that employ pneumatic fastener driving tools, a high degree of fastener placement accuracy is desired. Fastener placement may effect the structural integrity of a fastened joint, or significantly influence the appearance quality of cosmetically sensitive applications, such as millwork trim. Additionally, proper installation of millwork may require fasteners to be driven into irregular geometries, such as into grooves or onto raised features. It is often regarded as difficult to accurately place fasteners in these types of applications, because the contact arm and the trip foot are often shaped to engage primarily flat surfaces. Also, the cosmetically sensitive nature of most millwork materials encourages the use of the trip foot so as to reduce incidental scuffing or marking of these surfaces. The trip foot, as previously described, may reduce the operator's ability to accurately place a fastener in these applications, thereby increasing the chance of such scuffing or marking.
In an embodiment of the invention, a fastener driving device for use in driving a fastener into an elongated contoured portion of a workpiece is provided. The elongated contoured portion of the workpiece has a surface that is contoured in a direction perpendicular to a longitudinal direction of the elongated contoured portion. The fastener driving device includes a housing assembly that has a fastener drive track defined therein, a fastener driver reciprocally mounted for movement within the drive track, and a power operated system constructed and arranged to be actuated so as to move the fastener driver through successive operative cycles. Each cycle includes a drive stroke in which a fastener in the drive track is driven into a workpiece, and a return stroke. The fastener driving device also includes an actuating mechanism that includes a contact trip assembly and a trigger assembly constructed and arranged to actuate the power operated system in response to a predetermined cooperative movement between the contact trip assembly and the trigger assembly. The contact trip assembly includes a contact arm operatively connected with the trigger assembly and has a contoured contact foot for engaging the workpiece. The contact arm is constructed and arranged to move relative to the housing assembly when the contoured contact foot is pressed against the workpiece. The contoured contact foot has a contoured engaging surface that includes a recess that is shaped to generally complement the shape of the contoured surface of the workpiece.
In an embodiment, a fastener driving device for use in driving a fastener into an elongated contoured portion of a workpiece is provided. The elongated contoured portion has a surface that is contoured in a direction perpendicular to a longitudinal direction of the elongated contoured portion. The fastener driving device includes a housing assembly that has a fastener drive track defined therein, a fastener driver reciprocally mounted for movement within the drive track, and a power operated system constructed and arranged to be actuated so as to move the fastener driver through successive operative cycles. Each cycle includes a drive stroke in which a fastener in the drive track is driven into a workpiece, and a return stroke. The fastener driving device also includes an actuating mechanism that includes a contact trip assembly and a trigger assembly constructed and arranged to actuate the power operated system in response to a predetermined cooperative movement between the contact trip assembly and the trigger assembly. The contact trip assembly includes a contact arm operatively connected with the trigger assembly and has a contoured contact foot for engaging the workpiece. The contact arm is constructed and arranged to move relative to the housing assembly when the contoured contact foot is pressed against the workpiece. The contoured contact foot has a contoured, gently curved convex engaging surface that is shaped to generally complement the shape of the contoured surface of the workpiece such that when the contoured contact foot is pressed against the contoured surface of the workpiece, the engagement between the gently curved convex engaging surface and the workpiece (1) gently locates the contoured contact foot relative to the workpiece in the direction perpendicular to the longitudinal direction, and (2) allows the contoured contact foot to rotate about a pivot axis substantially parallel to the longitudinal direction. The gently curved convex engaging surface is aligned with the drive axis in a direction parallel to the longitudinal direction.
In an embodiment, a contoured contact foot for a fastener driving device for use in driving a fastener into an elongated contoured portion of a workpiece is provided. The elongated contoured portion has a surface that is contoured in a direction perpendicular to a longitudinal direction of the elongated contoured portion. The contoured contact foot is constructed and arranged to be connected to a contact trip arm of the fastener driving device. The contoured contact foot has a contoured engaging surface that includes a recess that is shaped to generally complement the shape of the contoured surface of a workpiece.
In an embodiment, a contoured contact foot for a fastener driving device for use in driving a fastener into an elongated contoured portion of a workpiece is provided. The elongated contoured portion has a surface that is contoured in a direction perpendicular to a longitudinal direction of the elongated contoured portion. The contoured contact foot is constructed and arranged to be connected to a contact trip arm of the fastener driving device. The contoured contact foot has a contoured, gently curved convex engaging surface that is shaped to generally complement the shape of the contoured surface of a workpiece such that when the contoured contact foot is pressed against the contoured surface of the workpiece, the engagement between the gently curved convex engaging surface and the workpiece (1) gently locates the contoured contact foot relative to the workpiece in the direction perpendicular to the longitudinal direction, and (2) allows the contoured contact foot to rotate about a pivot axis substantially parallel to the longitudinal direction. The gently curved convex engaging surface is aligned with a drive axis of the fastener driving device when contoured contact foot is connected to the contact trip arm.
In an embodiment, a combination of a fastener driving device for use in driving a fastener into an elongated contoured portion of a workpiece, and a plurality of contoured contact foot members is provided. The elongated contoured portion of the workpiece has a surface that is contoured in a direction perpendicular to a longitudinal direction of the elongated contoured portion. The fastener driving device includes a housing assembly that has a fastener drive track defined therein, a fastener driver reciprocally mounted for movement within the drive track, and a power operated system constructed and arranged to be actuated so as to move the fastener driver through successive operative cycles. Each cycle includes a drive stroke in which a fastener in the drive track is driven into a workpiece, and a return stroke. The fastener driving device also includes an actuating mechanism that includes a contact trip assembly and a trigger assembly constructed and arranged to actuate the power operated system in response to a predetermined cooperative movement between the contact trip assembly and the trigger assembly. The contact trip assembly includes a contact arm operatively connected with the trigger assembly at one end. The contact arm is constructed and arranged to move relative to the housing assembly when the contoured contact foot is pressed against the workpiece. Each contoured contact foot member is constructed and arranged to be removably connected to the contact arm at an end opposite the trigger assembly. Each contoured contact foot member has a different contoured engaging surface that is shaped to complement the shape of different contoured surfaces of the workpiece. The contoured engaging surface of one or more of the plurality of contoured contact foot members includes a recess.
In an embodiment, a method for driving a fastener into an elongated contoured portion of a workpiece with a fastener driving device is provided. The fastener driving device includes a housing assembly, a power operated system, and an actuating mechanism that includes a contact arm, a contoured contact foot connected to the contact arm, and a trigger assembly. The elongated contoured portion of the workpiece has a surface that is contoured in a direction perpendicular to a longitudinal direction of the elongated contoured portion. The contoured contact foot has a contoured engaging surface that includes a recess that is shaped to complement the shape of the contoured surface of the workpiece. The method includes engaging the recess of the contact foot with the complementary contoured surface of the workpiece so that the complementary shapes of the engagement prevent slippage of the contoured contact foot relative to the workpiece in the direction perpendicular to the longitudinal direction, and actuating the power operated system to drive the fastener by (1) pressing the contoured contact foot against the workpiece so that the contact arm moves relative to the housing assembly, and (2) moving a trigger of the trigger assembly from an inoperative position to an operative position.
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:
a is a partial side view of the fastener driving device of
b is a partial side view of the fastener driving device of
a is a partial side view of the fastener driving device of
b is a detailed view of
a is a partial side view of the fastener driving device of
b is a detailed view of
Referring now more particularly to the drawings, there is shown in
The fastener driving device 10 itself may be of any type. As shown, the fastener driving device 10 is power operated. Such power operation may be of any type, such as electrical, internal combustion, or pneumatic. The fastener driving device 10 as shown in
Specifically, the pneumatically powered fastener driving device 10 shown in
The reservoir 18 communicates with a manually operable trigger valve assembly 22, which controls the communication of the reservoir to a pilot pressure chamber 24 of a main valve assembly 26. The main valve assembly 26 is housed within a cap assembly 28, fixed to the top of a main housing section 30, that is integral with and extending generally perpendicular to the handle section 16, both of which form parts of the portable housing assembly 14.
Mounted within the main housing section 30 is a cylinder 32, an upper end of which cooperates with the main valve assembly 26 to enable the main valve assembly 26 to function in the usual fashion when in an inoperative position, wherein the pilot pressure chamber 24, under the control of trigger valve assembly 22 in its inoperative position, is communicated with the reservoir 18. When in its inoperative position, the main valve assembly 26 also functions to communicate the open upper end of the cylinder 32 with atmosphere through the cap assembly 28. An adjustable exhaust assembly, such as the assembly described by U.S. Pat. No. 6,431,429, which is incorporated herein by reference, may also be associated with the cap assembly 28 to further communicate air within the device 10 to atmosphere.
When the trigger valve assembly 22 is manually moved from its inoperative position into an operative position, the pilot pressure chamber 24 is shut off from communication with the reservoir 18 and communicated with atmosphere. The pressure from the reservoir 18 then acts upon the main valve assembly 26 to move it from its inoperative position into an operative position. In its operative position, the main valve assembly 26 functions to shut off the communication of the open upper end of the cylinder 32 with the atmosphere and to allow full peripheral communication thereof with the reservoir 18. A more detailed description of the operation of the trigger valve assembly is provided by U.S. Pat. No. 6,431,429, which is incorporated herein by reference.
Communication of the reservoir 18 with the open upper end of the cylinder 32 serves to drive a piston 34, slidably mounted within the cylinder 32, through a fastener drive stroke, which is completed when the piston 34 engages a shock absorbing bumper 36 mounted in the main housing section 30 below the lower end of the cylinder 32, which is fixed therein.
The drive stroke of the piston 34 constitutes one stroke of a two stroke cycle of movement that the piston 34 undergoes on a successive basis in accordance with the manual actuating movement of the trigger valve assembly 22. The other stroke of the piston 34, which constitutes a return stroke, is accomplished by a suitable return system 38. The return system may be of any type. As shown, the return system 38 is of the air plenum chamber type that includes one-way check valve openings 39 that extend through the cylinder 32 into a surrounding plenum chamber 41, also known as a plenum, formed between the exterior of the cylinder 32 and the interior of the main housing section 30.
The drive stroke of the piston 34 serves to move a fastener driver 40 connected therewith through a drive stroke within a drive track 42 formed within a nose piece assembly 44 fixed below the lower end of the main housing section 30, and forming a part of the portable housing assembly 14. The drive track 42 is substantially aligned with a drive axis DA. The drive stroke of the fastener driver 40 serves to drive a leading fastener from a supply of fasteners contained within a fastener magazine assembly 46 that has been laterally moved into the drive track 42 along a feed track 48 defined by the magazine assembly 46. As the piston 34 moves toward the end of the drive stroke, the check valve openings 39 are uncovered and the air under pressure in the cylinder 32 driving the piston 34 is allowed to enter into the plenum chamber 41. The lower end of the plenum chamber 41 is communicated by an opening 43 into the bottom of the cylinder 32 at the level of the bumper 36.
The bumper 36 is engaged by the lower surface of the piston 34 at the end of the drive stroke and is arrested thereby. As soon as the pressure in the cylinder 32 is relieved by the movement of the main valve assembly 26, the air pressure within the cylinder 32 is communicated with an outlet opening provided by the main valve assembly 26 communicating the air pressure within the cylinder 32 with an adjustable exhaust assembly. As soon as the air pressure is relieved, the air pressure which is contained in the plenum chamber 41 acts on the lower end of the piston 34 so as to effect a return stroke thereof. The air within the cylinder 32 displaced by the movement of the piston 34 through its return stroke is discharged through the outlet opening into the adjustable exhaust assembly and, from there, into the atmosphere.
The magazine assembly 46, which is fixed to the nose piece assembly 44 and extends below and is fixed to the handle section 16, may be of any type. The magazine assembly 46, as shown, is a conventional side loader that is capable of handling fasteners in a stick formation supply, as shown, or a coil formation supply of any configuration.
The trigger valve assembly 22 is manually actuated by an actuating mechanism which includes a trigger assembly 50 and the contact trip assembly 12. A complete actuation movement serves to move the trigger valve assembly 22 from its inoperative position into its operative position by the coordinated movement of the trigger assembly 50 and contact trip assembly 12, both of which may be of any conventional construction so as to require any coordination to effect operation. In the illustrated embodiment, actuation requires a specific sequential movement. That is, the cooperation between the trigger assembly 50 and the contact trip assembly 12 is such that the trigger valve assembly 22 will be moved from its inoperative position into its operative position only when the contact trip assembly 12 is first moved against the workpiece 200 and into its operative position and, thereafter, the trigger assembly 50 is manually moved into its operative position. Of course, the invention is not limited to devices that operate sequentially. For example, the device 10 may be configured so that the trigger assembly 50 may be manually moved from its inoperative position into its operative position before the contact trip assembly 12 is moved against the workpiece 200 into its operative position. Any sequence of moving the trigger assembly 50 and the contact trip assembly 12 between their respective inoperative positions to their operative positions to enable the trigger valve assembly 22 to move into its operative position is contemplated.
In the broadest aspects of the present invention, the device 10 may be adapted to handle any fastener configuration. However, in the embodiment shown, the feed track 48 is configured to receive therein a supply of finishing nail fasteners in stick formation. The magazine assembly 46 includes a pusher 54, the illustrated embodiment of which is shown as a sheet metal structure having a width slightly greater than the diameter of the finishing nails. The pusher 54 is slidably mounted in the feed track 48 and is spring-biased to move in a direction toward the drive track 42. Of course, in embodiments that include a coil type magazine assembly, a pawl and reciprocating piston of a conventional design may be used to feed the fasteners from the feed track 48 to the drive track 42. The illustrated embodiment is not intended to be limiting in any way.
The contact trip assembly 12, in addition to its biasing spring, which is shown at 62 in
As shown in greater detail in
The contoured contact foot 72 may be constructed from any material, including metal, rubber, or plastic, or any combination thereof. Preferably, the contoured contact foot 72 is molded from a plastic or rubber material that is rigid enough to withstand thousands of placements on workpieces, yet flexible enough to be able to be slightly deformed so that the contoured contact foot 72 may be connected to the contact arm 64, as would be understood by one of ordinary skill in the art, and explained in further detail below.
As shown in
A conventional contact foot 72′ is shown in
In an embodiment of the invention, as shown in
A side wall 78 extends upwardly from the bottom surface 74 so that it also surrounds the opening 76. The side wall 78 may include a plurality of alignment markers 80 on an outside surface 82 thereof that are positioned to indicate the position of the exit of the drive track 42. The alignment markers 80 may assist the user in locating the device 10 at the desired location on the workpiece 200, as the alignment markers 80 are substantially parallel to the drive axis DA of the drive track 42, and indicate the location of the drive axis DA relative to the rest of the contact foot 72. An inside surface 79 of the side wall 78 may include recesses and/or protrusions that complement the shape of the end of the lower portion 68 of the contact arm 64 so that the contoured contact foot 72 may snugly receive the end of the contact arm 64. This way, the contoured contact foot 72 should not separate from the contact arm 64 during normal use of the device 10, yet still be removable by the user when the user would like to change out the contoured contact foot 72.
As shown in
The actual profile of the engaging surface 84 will depend on the intended application. For example, in the embodiments illustrated in
As shown in
As shown in
As shown in
As shown in
In another embodiment of the contoured contact foot 72, illustrated in
With all of the embodiments of the invention disclosed herein, by providing a contoured engaging surface 84 on the contoured contact foot 72 that complements the target contoured surface 204 on the workpiece 200, the user may be able to receive tactile feedback when the device is properly positioned in a least two degrees of freedom. Such feedback may increase the speed at which successive fasteners may be driven.
In an embodiment, a combination of the fastener driving device 10 with a plurality of interchangeable contoured contact foot members 72 is provided. The interchangeable contoured contact foot members 72 may include any combination of the contoured contact foot members 72 disclosed herein, including the conventional contact foot 72′ illustrated in
In operation, a fastener may be driven into the elongated contoured portion 202 of the workpiece 200 with the fastener driving device 10 described above by engaging the complementary contoured surfaces of the contoured contact foot 72 and the workpiece 200 so that the complementary shapes of the engagement prevent slippage of the contoured contact foot 72 relative to the workpiece 200 in the direction perpendicular to the longitudinal direction of the workpiece 200. Once the surfaces are engaged, the power operated system of the fastener driving device 10 may be actuated by (1) pressing the fastener driving device 10 against the workpiece 200 so that the contact arm 64 moves relative to the fastener driving device 10, and (2) moving the trigger 50 from the inoperative position to the operative position, as described above. The actuation of the power system may be completed in either order, i.e., the trigger 50 may me moved before pressing the device 10 against the workpiece 200, or the device 10 may be pressed against the workpiece 200 before the trigger 50 is moved from the inoperative position to the operative position.
The descriptions above are intended to be illustrative, not limiting. Thus, it will be apparent to one skilled in the art that modifications may be made to the invention as described without departing from the scope of the claims set out below.