Angled point brad and method of forming it

Abstract: An obliquely collated strip of brads (100) useable in an angled magazine (50) of a fastener driving tool (10), each brad (30) having a head (70) on one end and a point (80) on an opposing end. The point (80) of each brad (30) of the collated strip (100) has a tip (90) defined by converging facets (91,92,93,94) to form an edge (96) or surface (91) at an acute angle relative to an axis of the brad (30). The edge (96) or surface (91) of each brad forms a substantially continuous edge (110) of the collated strip (100). The head (70) of each brad (30) of the collated strip (100) is arranged step-wise relative to the head of an adjacent brad (30). The step-wise arrangement of heads (70) form a stepped edge (120) substantially parallel to the substantially continuous edge (110) of the collated strip (100). The head of each brad (30) slopes at an angle relative to the axis of the brad (30), with the angle of the head (70) sloping oppositely relative to the angle of the substantially continuous edge (110) of the collated strip (100).

Description: The invention relates generally to brads useable in a fastener driving tool and methods of forming them and, more particularly, to obliquely collated strips of brads useable in fastener driving tools having an aftwardly swept magazine, and combinations thereof. The parallel arrangement of brads in a collated strip for use in fastener driving tools is known generally. The collated strip of brads is cohered usually by an adhesive material, like nitrocellulose, and is disposed in a magazine of the fastener driving tool wherein individual brads are sequentially fed into a channel of a nose-piece thereof. A driver blade is accelerated axially through the channel behind the brad and into engagement therewith to separate the brad from the collated strip and discharge the brad from an aperture of the nose-piece into a target material or workpiece, usually grained wood or particle board. Many powered finishing nail, or brad, driving tools have the magazine oriented at a right angle relative to the channel in the nose-piece. Other fastener driving tools advantageously aftwardly sweep the magazine from the nose-piece at an angle relative to the channel therein to improve clearance about the nose-piece and to facilitate handling and operation of the fastener driving tool, particularly while performing nailing operations in closed spaces, such as along corners of intersecting walls and ceilings. To accommodate fastener driving tools having an aftwardly swept magazine, the collated strip of brads must be arranged obliquely so that a leading edge of the collated strip of brads has substantially the same angular relationship, usually within two degrees more or less, to the longitudinal axis of the brad as the channel of the fastener driving tool nose-piece has to the magazine. US-A- 4,664,733 discloses a machine for offsetting a plurality of preformed fasteners adhered with a plasticized adhesive coating to form a strip of obliquely cohered fasteners before the adhesive coating hardens. The result is a collated strip of brads arranged obliquely and having a first stepped edge formed by the plurality of brad points and a second stepped edge formed by the plurality of brad heads. The point of each brad has a straight edge symmetrically formed by converging surfaces extending from opposing sides of the brad, wherein the edge is perpendicular to the longitudinal axis of the brad and is parallel to an upper surface of the head. This process of however requires complex machinery and additional processing steps that increase production costs. Other known methods of forming obliquely collated strips of brads for use in fastener driving tools having an aftwardly swept magazine include forming points on a parallel arrangement of wire members with a stepped cutting die oriented at an appropriate angle relative to the longitudinal axes of the wire members. According to these alternative methods, heads of the brads are formed on an opposing end portion of the wires with a stepped heading die, wherein the end portions of the wire members on which the heads are formed are cut with the same stepped cutting die used to form the points. In the known prior art, the point of each brad is formed either having a straight edge defined by converging surfaces extending from opposing sides of the brad as in US-A- 4,664,733, or the point of each brad is formed having a flat surface perpendicular to the longitudinal axis of the brad. In both configurations, however, the resulting obliquely collated strip of brads has a stepped edge formed by the plurality of brad points and another stepped edge formed by the plurality of brad heads, wherein each individual brad is configured substantially the same as those discussed above in connection with U.S. -A-4,664,733. Although these alternative methods of forming obliquely collated strips of brads has advantages over the method of U.S. -A-4,664,733, , including reduced manufacturing costs, they are nevertheless subject to some drawbacks. More particularly, the stepped cutting dies are expensive to fabricate. Additionally, variation in the diameter of the wire members causes misalignment of the stepped cutting and stepped heading dies relative to ends of the wire members during the cutting and heading operations. Misalignment of the stepped cutting die results in over-cutting of some wire members and incomplete cutting of others, which causes excessive wear on the cutting die and may prevent proper separation of the formed obliquely collated strip of brads from the wire members during the manufacture thereof. Misalignment of the stepped heading die results in formation of incomplete and distorted heads on the cut wire members, and causes excessive wear on the stepped heading die. In addition to the problems discussed above, improperly formed brads are susceptible to jamming in the channel of the nose-piece, and moreover are a suspected cause of poor penetration performance, possibly resulting from slippage of the driver blade off the head during fastening operations and from poorly formed points. Notably, in the past, it was believed generally that fastener points must be formed symmetrically in order to ensure adequate and accurate penetration into the workpiece, and that asymmetrically formed fastener points had an increased tendency to be deflected from the surface of the workpiece, a phenomenon referred to as skating. Asymmetrically formed points were also believed to be more susceptible to influence by wood grain, sometimes piercing through a side of the workpiece, which is an adverse effect known as shining. According to a first aspect of this invention a brad useable in a fastener driving tool, the brad comprises: a shank having a longitudinal axis and a head at a first end, the shank having substantially opposing fast and second sides and substantially opposing first and second edges; a point at a second end of the shank opposing the first end, the point having a tip defined by converging first and third facets, at least one of the first and second facets converging from corresponding substantially opposing first and second sides of the shank to form an edge at an acute angle relative to the longitudinal axis of the shank, and the third facet formed by a first or second edge of the shank. The invention also embraces a collated strip of brads for use with an angled magazine of a fastener driving tool, the collated strip comprising a number of brads in accordance with the first aspect of this invention arranged collectively in parallel, the substantially opposing first and second sides of the shank of each brad lying in corresponding first and second substantially parallel planes, and the edge or the planar surface of each brad forming a substantially continuous edge of the collated strip of brads, whereby the collated strip of brads is arranged obliquely. According to a further aspect of this invention a method of making a collated strip of brads useable in a magazine of a fastener driving tool, the method comprising: collectively arranging a plurality of wire members in parallel; forming a first substantially continuous edge on the plurality of collectively arranged wire members at an acute angle relative to the longitudinal axis of the plurality of collectively arranged wire members; forming a second substantially continuous edge on the plurality of collectively arranged wire members in a first cutting operation, the second substantially continuous edge being formed at an acute angle relative to a longitudinal axis of the plurality of collectively arranged wire members, the first substantially continuous edge being substantially parallel to the second substantially continuous edge; and, forming a head on each of the plurality of collectively arranged wire members in a heading operation performed on the first substantially continuous edge; the second substantially continuous edge forming a point on each of the plurality of collectively arranged wire members opposite a corresponding head formed on each of the plurality of collectively arranged wire members, whereby the collated strip of brads is arranged obliquely. Particular embodiments in accordance with this invention will now be described with reference to the accompanying drawings; in which:- Figure 1 is a partially sectioned side elevation of a powered fastener tool having an aftwardly swept magazine useable for driving brads arranged in an obliquely collated strip; Figure 2 is a side view of an obliquely collated strip of brads; Figure 3a is a side view of an individual brad of the obliquely collated strip of brads of Figure 2; Figure 3b is an end view along lines a-a of Figure 3a; Figure 3c is an opposing end view along lines b-b of Figure 3a; FIG. 3d is a side view of an alternative point configuration of an individual brad of the obliquely collated strip of brads of FIG. 2 which are not in accordance with this invention: FIG. 3e is an end view along lines e - e of FIG 3d; FIG. 3f is an opposing end view along lines f - f of FIG. 3d; FIG. 4 is a partial sectional view along lines c - c of FIG. 2; FIG. 5 is a schematic manufacturing flow diagram illustrating exemplary processes for making an obliquely collated strips of brads according to the present invention; FIG. 6a is a perspective view of an exemplary arrangement for manufacturing an obliquely collated strip of brads according to processes of the present invention ; and, FIG. 6b is a partial sectional view along lines d - d of FIG. 6a showing a portion of a stepped heading die and a partially formed obliquely collated strip of brads. FIG. 1 is a partial sectional view of a powered fastener driving tool 10 useable for driving brads arranged in an obliquely collated strip of brads. The fastener driving tool useable for this purpose has generally a driver blade 22 extendable along its longitudinal axis through a channel 24 of a nose-piece 20 and into engagement with an endmost fastener, or brad, 30 disposed within the channel 24 to separate the endmost brad 30 from the obliquely collated strip of brads 100 and discharge the brad 30 from an aperture 26 of the nose-piece 20 into a target material or workpiece, like wood, not shown in the drawing. The exemplary fastener driving tool 10 of FIG. 1 is of the type disclosed more fully in EP-A-0887155. The fastener driving tool 10 includes a handle 40 extending substantially radially from the longitudinal axis of the driver blade 22. In the exemplary embodiment, the handle 40 is disposed along a substantially perpendicular radial relative to the axis of the driver blade 22, but the handle 40 may more generally be disposed at some angle relative to the axis of the driver blade 22. The fastener driving tool 10 also includes a magazine 50 disposed at an angle relative to the longitudinal axis of the driver blade 22 for receiving and feeding individual brads 30 of the collated strip of brads 100 to the channel 24 of the nose-piece 20. FIG. 1 shows the magazine 50 extending aftwardly from the nose-piece 20 toward and below the handle 40, wherein the handle 40 and the magazine 50 are disposed on substantially the same side of the driver blade 22, as discussed further below. FIG. 2 is an obliquely collated strip of brads 100 useable in a fastener driving tool having an angled magazine, and FIGS. 3a-3c illustrate various views of a single brad 30 of the obliquely collated strip of brads of FIG. 2. More particularly, each brad 30 includes generally a shank 60 with a longitudinal axis having a head 70 at a first end and a point 80 at a second opposing end. FIG. 4 shows the shank 60 of each brad 30 having a race-track shaped cross-section, but the shank 60 may alternatively have other cross-sectional shapes including square, rectangular, polygonal, round, oval and Turk's-head shapes. Thus according to the exemplary race-track configuration of FIG. 4, the shank 60 has opposing first and second sides 62 and 63, which are parallel surfaces, and the shank 60 includes first and second curved ends 64 and 65 between the opposing sides 62 and 63. The point 80 of the brad 30 has a tip 90 defined by a first facet 92, a second facet 93, and a third facet 94, wherein at least one or both of the first and second facets 92 and 93 converge from corresponding substantially opposing first and second sides 62 and 63 of the shank 60 to form an edge 96 at an angle Φ relative to the longitudinal axis of the shank 60. The third facet 94 is formed by a third side of the shank 60, wherein the third side of the shank is one of the first or second curved ends 64 or 65 of the shank 60. The facets 92, 93 and 94 forming the tip 90 may have planar or curved surfaces, and the point 80 is generally asymmetric with respect to the longitudinal centerline of the shank 60 when viewed from either of the sides 62 and 63. In the exemplary embodiment, the first curved end 64 of the shank is the third side of the shank 60, wherein the third facet 94 is formed by the first curved end 64. FIGS. 3a-3c show the first and second facets 92 and 93 of the tip 90 being substantially planar, and the third facet 94 of the tip curved. In other embodiments, however, the third facet may also be planer, for example where the shank 60 has a square or rectangular cross-sectional shape. FIGS. 3a-3c also show the first and second facets 92 and 93 converging from the corresponding first and second opposing sides 62 and 63 of the shank 60 to form the edge 96 substantially symmetrically between the first and second opposing sides 62 and 63. In alternative embodiments, however, the edge 96 is not necessarily symmetrically disposed between the first and second sides 62 and 63. One of the first and second facets 92 or 93 may for example correspond with one of the first or second sides 62 or 63 of the shank 60 as discussed above. FIGS. 3d-3f show yet another alternative embodiment (which is not in accordance with the present invention), wherein the brad point 80 includes a substantially planar surface 91 disposed at an acute angle relative to the longitudinal axis of the shank 60. The substantially planer surface 91 is bounded by substantially opposing sides 62 and 63 and by opposing ends 64 and 65, which in the exemplary embodiment have curved surfaces thereby forming a race-track shaped cross-section as discussed above. The point 80 has a tip 90 defined by the substantially planer surface 91 disposed at an acute angle relative to the longitudinal axis of the shank 60, the substantially opposing first and second sides 62 and 63 of the shank 60, and by one of the first and second ends of the shank, which is end 64 in FIG. 3d. The head of the brads in the alternative embodiment of FIGS. 3d-3f is not shown but corresponds with the head 70 shown in the embodiment of FIGS. 3a-3c, respectively, discussed further below. As viewed from either side 62 or 63, the angle Φ between the edge 96 in the FIGS. 3a-3c, and the substantially planer surface 91 in FIGS. 3d-3f, and the longitudinal axis of the shank 60 is an acute angle between approximately 60 degrees and approximately 80 degrees generally, and in one preferred embodiment the angle Φ is approximately 70 degrees. The angle Φ corresponds substantially to the relative angle between the magazine 50 and the channel 24 of the nose-piece 30 of the associated tool, as discussed above. The head 70 of the brad 30 has a top surface 71 at an angle relative to the longitudinal axis of the shank 60 when viewed from the first or second side 62 and 63 of the shank 60, wherein the angle of the top surface 71 slopes oppositely relative to the angle of the edge 96 or the substantially planer surface 91, as shown best in FIGS. 2, 3a and 3d. The magnitude of the angle of the top surface 71 however is not necessarily the same as the magnitude of the angle of the edge 96 or surface 91, although they may be equivalent. FIGS. 3b and 3c show the head 70 of the shank 60 also having first and second opposing side portions 72 and 73 extending outwardly beyond the first and second side surfaces 62 and 63 of the shank. FIG. 2 shows a plurality of substantially identically configured brads 30 arranged collectively in parallel to form the obliquely collated strip of brads 100. In one preferred embodiment, the obliquely collated strip of brads 100 is composed of 50 brads. The substantially opposing first and second sides 62 and 63 of each brad 30 is in corresponding first and second substantially parallel planes of the obliquely collated strip of brads 100. In the embodiment of FIGS. 3a-3c, the edge 96 of each brad 30 forms a substantially continuous edge 110 of the obliquely collated strip of brads 100 shown in FIG. 2. In the alternative embodiment of FIGS. 3d-3f, the substantially planer surface 91 of each brad 30 similarly forms a substantially continuous edge of an obliquely collated strip of brads, which is not shown but is similar to the configuration of FIG. 2. The angle between the substantially continuous edge 110 and the longitudinal axis of the brads 30 is thus between approximately 60 degrees and approximately 80 degrees generally, and in one preferred embodiment the angle is approximately 70 degrees, as discussed above. In the exemplary embodiment, the first and second facets 92 and 93 of each brad 30 of the obliquely collated strip of brads 100 converge from the corresponding substantially opposing first and second sides 62 and 63 of the shank 60 to form the substantially continuous edge 110 substantially symmetrically between the first and second sides 62 and 63 of the plurality of collectively arranged brads 30 forming the obliquely collated strip of brads 100. The substantially continuous edge 110 may, however, be configured according to the alternative configurations of the edge 96 of individual brads 30 or according to the alternative configuration shown in FIGS. 3d-3f as suggested above. FIG. 2 also shows the head 70 of each brad 30 of the obliquely collated strip of brads 100 arranged step-wise relative to the head 70 of each adjacent brad 30, wherein the step-wise arrangement of heads 70 forms a stepped edge 120 substantially parallel to the substantially continuous edge 110 of the obliquely collated strip of brads 100. Also, the head 70 of each brad of the collated strip of brads has a top surface 71 at an angle relative to the longitudinal axis of the shank 60, wherein the angle of the top surface 71 of the head 70 slopes oppositely relative to the angle of the substantially continuous edge 110 of the obliquely collated strip of brads 100. FIG. 5 is a manufacturing flow diagram 200 illustrating schematically the manufacture of the obliquely collated strip of brads 100 according to an exemplary process of the invention. In a first step 210, a plurality of wire members 250 are collectively arranged in parallel as shown in FIG. 6a. In a preferred arrangement, fifty wire members are collectively arranged in parallel and then cut to form obliquely collated strips of brads 100 as discussed further below. The collectively arranged plurality of wire members 250 are cohered usually by an adhesive material, like nitrocellulose. In one method of manufacture, the wire members are subject to a wire flattening operation, usually by a rolling member, to provide the race-track shaped cross-section shown in FIG. 4. The wire flattening operation is generally performed before the coherence of the wire members with the adhesive material, or while the applied adhesive material is still plastic, before the adhesive material hardens. FIG. 5 shows a cutting operation 220, and FIG. 6a shows a manufacturing arrangement for performing the cutting operation 220 on the plurality of collectively arranged wire members 250 to form a first substantially continuous edge 252 at an acute angle relative to the longitudinal axis of the plurality of collectively arranged wire members 250. FIG. 6a shows the cutting operation 220 performed by cooperating cutting dies 260 and 270 movable substantially transversely relative to a direction of travel T of the plurality of collectively arranged wire members 250. The cutting dies 260 and 270 are arranged at an angle relative to the direction of travel T of the plurality of collectively arranged wire members 250 to form the first substantially continuous edge 252 at the acute angle Φ, as discussed above. A second substantially continuous edge, not shown, is formed on an end portion of a section of the plurality collectively arranged wire members 250 opposite the first substantially continuous edge 252, wherein the section of the plurality collectively arranged wire members 250 ultimately forms obliquely collated strip of brads. The second substantially continuous edge of the plurality of collectively arranged wire members 250 is also formable by the cooperating cutting dies 260 and 270 of FIG. 6a in a cutting operation, which occurs after the plurality of collectively arranged wire members 250 have been moved toward the heading die 280 in the direction T subsequent to a previous cutting operation forming the first edge 252. The second substantially continuous edge is formed identically and parallelly to the first substantially continuous edge 252, and corresponds to the substantially continuous edge 110 of the obliquely collated strip of brads 100 shown in FIG. 2. FIG. 6a also shows converging cutting surfaces 262 and 264 of the cutting die 260 and converging cutting surfaces 272 and 274 of the cutting die 270 forming corresponding continuous cutting edges 265 and 275, respectively. The cutting edges 265 and 275 of the cutting dies 260 and 270 form the first and second facets 92 and 93 of the substantially continuous edge 110 on the resulting obliquely collated strip of brads 100, as shown in FIGS. 2 and 3a-3c. The continuous cutting edges 265 and 275 of the cutting dies 260 and 270 are considerably less costly to fabricate than prior art stepped cutting dies. Also, the continuous cutting edges 265 and 275 of the cutting dies 260 and 270 are subject to considerably less degradation by the wire members during the cutting operations in comparison to prior art stepped cutting dies. The alternative point configuration of FIGS. 3d-3f may be formed by cutting dies 260 and 270 having corresponding substantially complementary stepped surfaces 267 and 277, which shear the wire members 250. The alternative substantially complementary stepped surfaces 267 and 277 of the cutting die 260 and 270 are shown in phantom lines in FIG. 6a. The alternate cutting die configurations also have continuous cutting edges which are less costly to fabricate and are subject to less degradation in comparison to prior art stepped cutting dies. Another step illustrated by the flow diagram of FIG. 5 is a heading operation 240 performed on one of the substantially continuous edges of the plurality of collectively arranged wire members 250 to form a head on each of the plurality of collectively arranged wire members 250. FIG. 6a shows the heading operation 240 performed by a heading die 280 movable in a direction H relative to the plurality of collectively arranged wire members 250, which are generally supported by means known in the art during the heading operation 240. In one preferred mode of practicing the invention, the cutting operation 220 occurs simultaneously with the heading operation 240, although the cutting operation 220 may alternatively occur either before or after the heading operation 240, so long as means are provided for supporting the plurality of collectively arranged wire members 250 during the heading operation 240. FIG. 6b is a partial sectional view of the heading die 280 of FIG. 6a showing the heading die 280 having a plurality of flat surfaced dies 282 arranged adjacently in a stepped configuration at an angle Φ corresponding to the angle of the first substantially continuous edge 252. Each flat surfaced die 282 is disposed transverse to the longitudinal axis of the plurality of collectively arranged wire members 250, and each flat surfaced die 282 corresponds to one of the plurality of collectively arranged wire members 250. FIG. 6b also shows a portion of the first substantially continuous edge 252 of the plurality of collectively arranged wire members 250 after the cutting operation 220 but before the heading operation 240. The angle of the stepped heading die 280 is parallel to the angle of the first substantially continuous edge 252 of the plurality of collectively arranged wire members 250. In operation, the heading die 280, and more particularly the plurality of flat surfaced dies 282 thereof apply an axial compressive force to a corresponding wire member of the plurality of collectively arranged wire members 250 along the first substantially continuous edge 252 thereof. Notably, during the heading operation 240, each flat surfaced die 282 unexpectedly forms a head 70 on the corresponding wire member having a top surface 71 at an angle sloping oppositely relative to the angle of the first substantially continuous edge 252 before the heading operation. According to this aspect of the invention, the first substantially continuous edge 252 of the plurality of collectively arranged wire members 250 is formed into the stepped head edge 120 of the obliquely collated strip of brads 100, and the second substantially continuous edge of the plurality of collectively arranged wire member 250 corresponds to the substantially continuous edge 110 of the obliquely collated strip of brads 100, wherein the head 70 of each brad 30 slopes oppositely relative to the corresponding edge 96 as shown in FIG. 2. In an alternative method of making the obliquely collated strip of brads 100, the top surface 71 of each head 70 is formed substantially 90 degrees relative to the longitudinal axis of the shank 60. For this purpose, the plurality of flat surfaced dies 282 of the heading die 280 of FIG. 6b are each arranged at an angle, which is more parallel to the first substantially continuous edge 252 than is shown in FIG. 6a. According to this method, the angle between the flat surfaced dies 282 and the longitudinal axis of the plurality of wire members 250 is, for example, approximately 85 degrees, as measured counter-clockwise from the flat surfaced die 282 to the shank axis, wherein the precise angle may be determined without undue experimentation. FIG. 1. shows the obliquely collated strip of brads 100 disposed in an angled magazine 50 of the powered fastener driving tool 10, wherein the magazine sequentially feeds individual brads 30 of the obliquely collated strip of brads 100 into the channel 24 of the nose-piece 20, wherefrom the brads 30 are subsequently discharged by the driver blade 22. The handle 40 and the magazine 50 are disposed on substantially the same side of the driver blade 22 as shown in FIG. 1. As discussed above and shown in FIGS. 2 and 3, each brad 30 of the obliquely collated strip of brads 100 has a shank with a longitudinal axis, the shank having on one end a head 70 and on an opposing end a point 80 with a tip 90. The obliquely collated strip of brads 100 is disposed in the magazine 50 so that as the individual brads 30 are fed into the channel 24 of the nose-piece 20, the head 70 of the brad 30 is disposed nearest the driver blade 22 and the point 80 of the brad 30 is disposed nearest the aperture 26 of the nose-piece 20. FIG. 1 shows the angle of the substantially continuous edge 110 of the obliquely collated strip of brads 100 disposed in the magazine 50 relative to the longitudinal axis of the brads 30 being substantially the same as the angle of the magazine 50 relative to the axis of the driver blade 22, which is generally parallel to the longitudinal axis of the brads 30. In operation, the end 64 of the shank 60 defining the tip 90 of each brad 30 is fed first into the channel 24 of the nose-piece 20 by the magazine 50, wherein the end 64 faces away from the direction in which the handle 40 extends. According to this aspect of the invention, the tip 90 of each brad 30 disposed in the channel 22 is located along the end 64 of the brad 30, which is the endmost portion of the brad 30 farthest away from the magazine 50. The point 90 on the brad 30 improves the penetration performance of the brad 30 into the workpiece, notably without any deflection of the brad therefrom, the phenomenon known as skating discussed above, and without any observable adverse effect on brad penetration caused by wood grain, which may cause shining. Table I below, entitled Penetration Performance Comparison, summarizes test results obtained by driving (1 1/2 inch) 37.5mm angled chisel point brads of the present invention and (1 1/2 inch) 37.5mm prior art non-angled chisel point brads into an Oak wood with a pneumatic fastener driving tool operated at three different air supply pressures. PENETRATION PERFORMANCE COMPARISON TEST (psi) (BAR) NO. TESTS PERFORMED PRIOR ART (Ave. Drive Depth) INVENTION (Ave. Drive Depth) (70 psi) 4 2/3 20 (0.871 inches) 22.1mm (0.893 inches) 22.7mm (85 psi) 5 2/3 25 (1.183 inches) 30.0mm (1.210 inches) 30.7mm (90 psi) 6 18 (1.318 inches) 35.5mm (1.339 inches) 34.0mm The results of Table 1 show that the novel angled chisel point brads 30 of the present invention tend to penetrate deeper into the target material, or workpiece, in comparison to prior art non-angled chisel point brads. Table II below, entitled Shine Comparison, summarizes test results obtained by driving 134 (2.5 inch) 63.5mm novel angled chisel point brads of the present invention and (134 2.5 inch) 63.5 mm prior art non-angled chisel point brads into various wood grains with a pneumatic fastener driving tool. SHINE COMPARISON TOTAL TESTED TOTAL SHINED PRIOR ART 134 48 INVENTION 134 28 The results of Table II indicate that the angled chisel point brads of the present invention are not more likely to shine than prior art non-angled chisel point brads, and in fact the results of Table II suggests that the novel angled chisel point brads of the present invention are less likely to shine than prior art non-angled chisel point brads, which suggests further that the novel angled chisel point brads of the present invention are less likely to be influenced by wood grain. According to another aspect of the invention shown in FIG. 1, each brad 30 is disposed in the channel 24 of the nose-piece 20 so that the angle of the head 70 slopes oppositely relative to the angle of the magazine 50. The sloping angle of the brad head 70 tends to improve contact between a tip portion 23 of the driver blade 22 and the head 70 as the fastener driving tool recoils while driving the brad 30 into the workpiece. More particularly, FIG. 1 shows the fastener driving tool 10 recoiling in a direction R, and pivoting usually about the tool operator's wrist and elbow, which are extending from the operator's hand gripping the handle 40. The angled head 70 of the brad 30 slopes in a direction that may tend to keep the tip 23 of the driver blade 22 in more square contact with the brad head 70 as the fastener driving tool 10 recoils, thereby possibly compensating for recoil of the tool. As a result, the tendency of the driver blade 22 to slip off the brad head 70 may be reduced, which correspondingly reduces the possibility that the workpiece will be damaged by a misguided driver blade tip 23. In addition to the improved penetration performance resulting from the novel angled point 80, any improved contact between the driver blade 22 and brad 30 also very likely contributes to the improved penetration performance of the brad 30 into the workpiece.

Claims: A brad (30) useable in a fastener driving tool, the brad (30) comprising: a shank (60) having a longitudinal axis and a head (70) at a first end, the shank (60) having substantially opposing first and second sides (62,63) and substantially opposing first and second edges (64,65); a point (80) at a second end of the shank (60) opposing the first end, the point (80) having a tip (90) defined by converging first (92), second (93) and third (94) facets, at least one of the first and second facets (92,93) converging from corresponding substantially opposing first and second sides (62,63) of the shank to form an edge (96) at an acute angle relative to the longitudinal axis of the shank (60), and the third facet (94) formed by a first or second edge (64,65) of the shank. A brad according to claim 1, in which the first and second facets (92,93) both converge from the corresponding substantially opposing first and second sides (62,63) of the shank (60) to form the edge (96) substantially symmetrically between the first and second sides (62,63) of the shank (60). A brad according to claim 1 or claim 2, in which the substantially opposing first and second sides (62,63) of the shank are parallel, and in which the shank has substantially opposing curved first and second edges (64,65), so that the shank (60) has a substantially oval cross-section. A brad according to any one of the preceding claims, in which the angle of the edge (96) or of the substantially planar surface (91) is approximately 70 degrees relative to the longitudinal axis of the shank (60). A brad according to any one of the preceding claims, in which the head (70) has a top surface (71) at an angle relative to the longitudinal axis of the shank (60), the angle of the top surface (71) of the head sloping oppositely relative to the angle of the edge (96) or planar surface (91). A collated strip (100) of brads for use with an angled magazine of a fastener driving tool, the collated strip comprising a number of brads in accordance with any one of the preceding claims arranged collectively in parallel, the substantially opposing first and second sides (62,63) of the shank (60) of each brad (30) lying in corresponding first and second substantially parallel planes, and the edge (96) or the planar surface (91) of each brad (30) forming a substantially continuous edge (110) of the collated strip (100) of brads, whereby the collated strip (100) of brads is arranged obliquely. A collated strip of brads according to claim 6, in which the head (70) of each brad (30) of the collated strip (100) is arranged step-wise relative to the head (70) of an adjacent brad (30) of the collated strip (100), the step-wise arrangement of heads (70) forming a stepped edge (120) substantially parallel to the substantially continuous edge (110) of the collated strip of brads (100). An collated strip of brads (100) in accordance with claim 6 or 7, in combination with a powered fastener driving tool (10) having a blade member (22) moveable along its longitudinal axis through a channel (24) of a nose-piece (20), the fastener driving tool (10) having a handle (40) extending substantially normally from the axis of the driver blade (22), and the fastener driving tool (10) having a magazine (50) at an angle relative to the axis of the driver blade (22) for receiving the collated strip of brads (100) and feeding individual brads (30) into the channel (34) of the nose-piece (20), the handle (40) and the magazine (50) extending through the same side of the drive blade (22), and the collated strip of brads (100) being oriented in the magazine (50) so that the edge (64,65) of the shank (60) defining the tip (90) of each brad (30) is fed first into the channel (22) of the nose-piece (20), whereby the edge (64,65) of the shank defining the tip (90) of each brad (30) faces away from the handle (40) when the brad (30) is disposed in the magazine (50). A method of making a collated strip (100) of brads useable in a magazine (50) of a fastener driving tool (10), the method comprising: collectively arranging a plurality of wire members (250) in parallel; forming a first substantially continuous edge (252) on the plurality of collectively arranged wire members (250) at an acute angle relative to the longitudinal axis of the plurality of collectively arranged wire members (250); forming a second substantially continuous edge (110) on the plurality of collectively arranged wire members (250) in a first cutting operation, the second substantially continuous edge (110) being formed at an acute angle relative to a longitudinal axis of the plurality of collectively arranged wire members (250), the first substantially continuous edge (252) being substantially parallel to the second substantially continuous edge (110); and, forming a head (70) on each of the plurality of collectively arranged wire members (250) in a heading operation (280) performed on the first substantially continuous edge (252); the second substantially continuous edge (110) forming a point (90) on each of the plurality of collectively arranged wire members (250) opposite a corresponding head (70) formed on each of the plurality of collectively arranged wire members (250), whereby the collated strip of brads (100) is arranged obliquely.

Inventors: SUTT EDWARD G JR, SUTT, EDWARD G., JR.
Applicants: ILLINOIS TOOL WORKS, ILLINOIS TOOL WORKS INC.
Application year: 1998
Main classification: F16B15
IPC codes: B21G3, F16B15, B21G1