Washer-dispensing and fastener-driving machine and a stackable washer for it

Abstract: A machine and washer (18) for fastening one or more layers of roofing material (12) to an underlayment, includes a chute (50) which receives a stack of washers (18), a shuttle (70) which displaces a single washer (18′) to a separated position when moves in one direction, to which the shuttle is biased and releases the single washer (18′) when moves oppositely, and a gate (80), which cooperates with camming surfaces (18b) on the respective washers (18), restrains the overlying washer (18″) in the stack (S) against being displaced with the single washer (18′) and restrains the single washer (18′) from being displaced from the separated position. Various components are provided by linking a stand-up screw gun (160 Figure 1) of a known type to the shuttle. The stackable washer (18) is embossed (352,354,356,358) so that each such washer and like overlying and underlying washers in a stack contact each other at three or more places, which define tangent planes intersecting planes defined by planar areas on such washers at angles more than 45° but less than 90° whereby such washers are spaced from each other around their entire peripheries (306) (Figures 22 and 23). Notches (64,66) in the washers (18) cooperate with ribs (60,62) in the chute (50) to ensure that a stack (S) of the washers is orineted properly when fitted into the chute (50).

Description: This invention pertains to an improved machine for fastening one or more layers of roofing material, such as a blanket of roofing insulation or a roofing membrane, to an underlayment, such as a wooden roof or a corrugated metal roof. The machine dispenses roofing washers individually onto the roofing material and drives a fastener having a head, such as a screw, through a central aperture of each washer, through such material, and into the underlayment, until the fastener bears against the washer. Various portable or semi-portable machines are known which dispense roofing washers individually onto roofing material, such as a blanket of roofing insulation or a roofing membrane, and which drive a fastener having a head, such as a screw, through the central aperture of such a washer, through the roofing material, and into an underlayment, such as a wooden roof or a corrugated metal roof, until the fastener bears against the washer. Herein, terms such as "roof" and "roofing" are to be broadly understood, so as to cover roofs, decks, ceilings, and similar structures. Such a portable or semi-portable machine according to the preamble of claim 1 is exemplified in Boegel U.S. Patent No. 4,246,939 wherein different mechanisms are disclosed for dispensing washers individually from a stack of washers in a magazine. In such a portable or semi-portable machine, it is known to place a weighted plunger onto the uppermost washer in the stack to restrain the washers in the stack from cascading from the stack if the magazine is tipped so as to tip the stack. Another such machine is exemplified in Mays U.S. Patent No. 4,657,167 wherein different mechanisms are disclosed (see FIGURES 3, 4, and 5 and FIGURES 6 through 10) for dispensing washers (which therein are called washer-like plates or disks) from a stack of washers in a magazine. No provision is disclosed to restrain the washers in the stack from cascading from the stack if the magazine is tipped so as to tip the stack. Tipping is required (see column 4, lines 31 through 36) to allow laterally mounted wheels of the disclosed machine to roll on an underlying surface. Roofing washers of particular interest suitable for use in dispensing and fastening machines are disclosed in Dewey U.S. Patent Des. 263,678, Dewey U.S. Patent Des. 263,927, and Dewey U.S. Patent Des. 263,928, which are assigned to Illinois Tool Works Inc. of Chicago, Illinois, the applicant hereof. Each washer has a central aperture, which is adapted to receive a fastener, and is embossed with a pattern of ribs so as to have positive relief and planar areas on its upper face and negative relief and planar areas on its lower face. The ribs on such washers are functional, as well as ornamental, since the ribs strengthen and rigidify the washers, which can thus be made from thin blanks. Other washers of particular interest are those disclosed in our co-pending divisional application filed on the same day and entitled "Stackable washer". Washers with countersunk apertures are preferred for overlying more compressible material, such as a blanket of roofing insulation, whereas washers without countersunk apertures are preferred for overlying less compressible material, such as a roofing membrane, which would be typically applied over a blanket of roofing insulation. It is desirable to countersink the heads of fasteners used to fasten a blanket of roofing insulation to an underlayment, if a roofing membrane is to be later applied over the blanket of roofing insulation, in an effort to avoid puncturing the roofing membrane where the fastener heads would underlie the roofing membrane and where a worker might step carelessly or unwittingly. Also of particular interest, screw guns equipped with screw-feeding attachments, so-called stand-up screw guns, are exemplified in Murray U.S. Patent No. 3,960,191, Dewey U.S. Patent No. 4,236,555, and Dewey U.S. Patent No. 4,397,412, which are assigned to Illinois Tool Works Inc., the assignee hereof. Such stand-up screw guns, as known heretofore, are not capable of dispensing washers but are used to drive screws through central apertures of manually placed washers, through roofing materials, and into underlayments. Such stand-up screw guns, as sold by ITW-Buildex (a division of Illinois Tool Works Inc.) of Itasca, Illinois, under its ACCUDRIVE XL trademark, have enjoyed commercial success in the United States in recent years. Although known portable or semi-portable machines which dispense roofing washers individually onto roofing material, such as a blanket of roofing insulation or a roofing membrane, and which drive a fastener having a head, such as a screw, through a central aperture of each washer, through the roofing material, and into an underlayment, such as a wooden roof or a corrugated metal roof, until the fastener bears against such washer, have proved to be generally satisfactory, there has been a need for an improved machine having such capabilities. According to this invention, a washer dispensing and fastener-driving machine for use with stackable roofing washers having central apertures and for use in fastening roofing material, such as a blanket of roofing insulation or a roofing membrane, to an under-layment, such as a wooden roof or a corrugated metal roof, by fasteners having heads with one washer between the head of each fastener and material, comprises: a base; a chute, which is supported by the base; a shuttle, which is mounted on the base for horizontal movement between a normal position and a displaced position, which is adapted to engage a single washer from the stack of roofing washers received by the chute when the shuttle is in the displaced position, which is adapted to displace the single washer from the stack to a separated position by positive engagement of the shuttle with the single washer as the shuttle moves from the displaced position to the normal position, and which is adapted to release the single washer in the separated position as the shuttle next moves from the normal position to the displaced position; fastener-driving means adapted to be operator-actuated for driving a fastener through the central aperture of the single washer while the single washer is in the separated position and the shuttle is in the displaced position; characterised in that the machine further comprises: a washer-restraining means movable between an upper and a lower position, biased to the lower position, and arranged such that in the upper position, only the single washer engaged in the shuttle may pass below the washer-restraining means, and in the lower position, none of the washers in the stack or a washer in the separated position can pass below the washer-restraining means; a shuttle biasing means arranged to bias the shuttle to the normal position but allow the shuttle to be forcibly moved to the displaced position; and a shuttle-moving means arranged to be operator-actuated and to be normally de-actuated for moving the shuttle forcibly from the normal position to the displaced position when actuated and for moving the shuttle as biased by the shuttle-biasing means from the displaced position to the normal position when deactuated; and, in that the chute is adapted to receive a stack of roofing washers to be individually dispensed by the machine. Preferably the machine dispenses the washers individually onto such material, at spaced locations, and drives a fastener through a central aperture of each washer, through the material, and into the underlayment, until the fastener bears against the washer. Preferably, the washers are embossed so as to form camming surfaces in suitable patterns on one broad face of each washer, and, if the washers are stacked so that the broad face formed with camming surfaces on each washer is its upper face, such means may comprise a gate, which is mounted to the base for movement toward and away from a lowermost position. The gate, which is biased toward the lowermost position, provides sufficient clearance for all or substantially all of a single washer being displaced by the shuttle from the stack to the separated position to pass beneath the gate but insufficient clearance for any overlying washer in the stack to pass beneath the gate with the single washer. The gate, which is cammed upwardly by camming surfaces on the upper face of the single washer as the single washer is displaced by the shuttle, so as to allow the single washer to pass beneath the gate, engages camming surfaces on the upper face of the single washer so as to restrain the single washer against being displaced from the separated position as the shuttle next moves from the normal position to the displaced position. Preferably, the machine is for use with stackable roofing washers embossed so as to form camming surfaces in such a pattern on one broad face of each washer, stacked so that the broad face formed with camming surfaces on each such washer is its upper face, and provided at the periphery of each washer with at least one notch, preferably with two such notches at spaced locations on its periphery, as exemplified by an improved washer described in our co-pending divisional application filed on the same date and entitled "Stackable washer", the chute is provided with a rib corresponding to each such notch, the rib or ribs being fittable into the notch or notches of each such washer and of like overlying and underlying washers in a stack received by the chute to restrain such washers against cascading from the stack if the chute is tipped so as to tip the stack. There is no need for a weighted plunger to restain such washers against cascading from the stack. Moreover, the washer-dispensing and fastener-driving machine provided by this invention comprises shuttle-biasing means for biasing the shuttle to the normal position but permitting the shuttle to be forcibly moved from the normal position to the displaced position and shuttle-moving means arranged to be operator-actuated and to be normally deactuated for moving the shuttle forcibly from the normal position to the displaced position when actuated and for moving the shuttle as biased by the shuttle-biasing means from the displaced position to the normal position when deactuated, along with fastener-driving means adapted to be operator-actuated for driving a fastener through the central aperture of the single washer while the single washer is in the separated position and the shuttle is in the displaced position. The shuttle-biasing, shuttle-moving, and fastener-driving means may be advantageously provided by linking a stand-up screw gun of a type exemplified in Murray U.S. Patent No. 3,960,191, Dewey U.S. Patent No. 4,236,555, and Dewey U.S. Patent No. 4,397,412 to the shuttle, via a mechanical linkage. The base, the chute, and the shuttle, as combined with such a linkage, may be thus regarded as an attachment for such a screw gun, which can be independently used without a washer-dispensing capability. Particular embodiments of washers and washer dispensing and fastener-driving machines in accordance with this invention will now be described with reference he accompanying drawings, in which:- Figure 1 is a perspective view of the whole machine; Figures 2 and 3 respectively are enlarged, fragmentary, perspective views taken from different directions to show lower portions of the machine; Figure 4 is a fragmentary exploded view of some components of the machine; Figure 5 is a partly sectioned, plan of lower portions of the machine with some components removed to allow other components to be better shown, where sectioned, Figure 5 is taken along a plane indicated by line 5--5 of Figure 3 in a direction indicated by arrows; Figures 6 and 7 are partly fragmentary, side elevations of lower portions of the machine; with Figure 6 showing the shuttle in a displaced position; Figure 8 is a slightly enlarged, quarter-turn rotated, fragmentary, perspective detail of a screw-receiving tube shown fragmentarily in Figure 6; Figures 9 and 10 are enlarged, fragmentary details of certain components of the machine as shown in Figures 6 and 7 respectively; Figures 11 and 12 are further enlarged, fragmentary details of the gate and shuttle of the machine; Figure 13 is a front elevation of the machine; Figure 14 is a slightly enlarged, partly fragmentary, exploded perspective detail of the shuttle and gate; Figure 15 is a slightly reduced, partly fragmentary side elevation showing a screw-feeding tube; Figure 16 is a somewhat enlarged, slightly, rotated, fragmentary detail of elements shown in Figure 15; Figure 17 is a fragmentary, section taken along line 17--17 shown in Figure 16 in a direction indicated by arrows. Figure 18 is a perspective view of a stack of roofing washers in a container having a removable lower cover; Figure 19 is a greatly enlarged, partly fragmentary, exploded, perspective view of the stack of roofing washers in the container; Figure 20 is a plan of a preferred form of such a washer; and, Figures 21, 22, and 23 are greatly enlarged, fragmentary, sectional views, as taken along lines 21--21, 22--22, and 23--23 respectively of Figure 20 in directions indicated by arrows. As shown in Figures 1 to 17, a washer-dispensing and fastener-driving machine 10, which constitutes a preferred embodiment of the washer-dispensing and fastener-driving machine provided by this invention, fixes a blanket of roofing insulation, to an underlayment 14, such as a wooden roof, by screws 16 of a known type having hexagonal heads and integral washers and with a roofing washer 18 between the head and integral washer of each screw 16 and the sheet 12. Suitable screws having hexagonal heads and integral washers are available commercially from ITW Buildex (a division of Illinois Tool Works Inc.) of Itasca, Illinois, under its HEXCEL trademark. The machine 10 dispenses such washers 18 individually onto the sheet 12, at spaced locations, and drives a screw 16 through a central aperture 20 of each roofing washer 18, through the sheet 14, and into the underlayment 14, until the head and integral washer of the screw 16 bear against the roofing washer 18. The machine 10 is equipped with a roller 22, which enables the machine 10 to be manually moved to another location. The machine 10 comprises a base 30 with a front portion, as shown at its lower right in FIGURE 1, a rear portion, as shown at its upper left in FIGURE 1, and intermediate portions between its front and rear portions. The machine 10 is assembled with machine screws of a conventional type having enlarged heads with hexagonal sockets, as shown, from various components, namely opposite, upright, side plates 32, 34, a shelf 36, which is mounted between the plates 32, 34, at the front portion of the base 30, a brace 38, which is mounted between the plates 32, 34, in the rear portion of the base 30, and a U-shaped bracket 40, which is mounted between the plates 32, 34, in an intermediate portion of the base 30. The bracket 40 has a bight 42, which has a central aperture 44, and opposite, upright, end portions 46, each of which is mounted to a respective one of the side plates 32, 34. The roller 22 is mounted for free rotation on an axle 48, which is supported at its ends by the plates 32, 34 respectively. Rather than a solid roller as shown, a spool-like roller (not shown) having two wheel-like portions or separate wheels (not shown) may be instead used. The machine 10 comprises a washer-receiving chute 50, which is adapted to receive a stack of washers 18, each washer 18 being spaced from each other washer in the stack around their entire peripheries. The chute 50 is defined by a front wall 52, a rear wall 54, and side walls constituted by portions of the side plates 32, 34, between the walls 52, 54. The walls 52, 54, are mounted between the side plates 32, 34, in an intermediate portion of the base 30, between the shelf 36 and the bracket 40. The front wall 52 has a larger, V-shaped cutout 56, which facilitates loading the chute 50 with the stack of such washers 18. The rear wall 54 has a smaller, V-shaped cutout 58, which provides clearance for a crosspiece to be later described. The plate 32 is provided with a vertical rib 60, which is spaced by a given distance (see FIGURE 5) from the front wall 52, where a portion of the side plate 32 provides a side wall of the chute 50. The plate 34 is provided with a vertical rib 62, which is spaced by a greater distance (see FIGURE 5) from the rear wall 54, where a portion of the side plate 34 provides a side wall of the chute 50. The ribs 60, 62, which may be advantageously provided by machined inserts (not shown) in machined grooves (not shown) in the side plates 32, 34, fit into and cooperate with notches 64, 66, in the lateral edges of each roofing washer 18 in the stack in a manner to be later described, thereby to restrain the roofing washers 18 in the stack against cascading from the stack if the machine 10 including the chute 50 is tipped so as to tip the stack. The ribs 60, 62, cause the chute 50 to be assymetrically shaped for a purpose to be later described. The machine 10 comprises a shuttle 70, which is mounted to the base 30 for horizontal movement between a normal position, in which the shuttle 70 is shown in FIGURES 6 and 9, and a displaced position, in which the shuttle 70 is shown in FIGURES 7 and 10. The shuttle 70 is biased toward the normal position in a manner to be later described. The shuttle 70 has opposite, parallel, side edges 72, each of which fits slidably into a longitudinal groove 74 (see FIGURE 13) in a respective one of the side plates 32, 34. A rear portion of the shuttle 70 is recessed (see FIGURE 14) so as to adapt the shuttle 70 to engage a single washer 18' from the stack (see FIGURE 10) when the shuttle 70 is in the displaced position, the single washer 18' being the lowermost washer in the stack S, and to displace the single washer 18' from the stack to a separated position (see FIGURE 9) by positive engagement of a front edge 76 of the recessed rear portion of the shuttle 70 with a trailing edge of the single washer 18' as the shuttle 70 moves from the displaced position to the normal position. The shuttle 70 has a rearwardly opening, U-shaped cutout 78, in its recessed rear portion, so as to accommodate a countersunk portion of the single washer 18'. The shuttle 70 thus is adapted to release the single washer 18' in the separated position as the shuttle 70 next moves from the normal position to the displaced position. The machine 10 comprises a gate 80, which restrains the overlying washer 18'' in the stack against being displaced from the stack with the single washer 18' as the shuttle 70 moves from the displaced position to the normal position, and which restrains the single washer 18' from being displaced from the separated position as the shuttle 70 moves from the normal position to the displaced position after having displaced the single washer 18' from the stack to the separated position. The gate 80 is mounted to the base 30, in an inverted, V-shaped cutout 82 in the rear wall 54 of the chute 50, for vertical movement through a limited range toward and away from a lowermost position, in which the gate 80 is shown in FIGURE 9. The gate 80 has upwardly facing portions conforming to the cutout 82, as shown, so as to center the gate 80 when the gate 80 is moved to an uppermost position, in which the gate 80 engages upper edges of the cutout 82. An upstanding tongue 84, which is an integral extension of the gate 80, fits slidably into a downwardly opening groove 86 in the rear wall 54 of the chute 50. The gate 80 is biased downwardly, toward the lowermost position, by a pair of coiled springs 88, which are seated in upwardly opening notches 90 in the tongue 84, and which bear against an upper edge of the groove 86. In the lowermost position, the gate 80 bears at its lower edge against the shuttle 70, either at opposite edges of the shuttle 70 so as to span the recessed rear portion of the shuttle 70, when the shuttle 70 is in the displaced position, or across the shuttle 70, when the shuttle 70 is in the normal position. In the lowermost position, the gate 80 provides sufficient clearance for the single washer 18' being displaced by the shuttle 70 from the stack to the separated position to pass beneath the gate 80 but insufficient clearance for the overlying washer 18'' in the stack also to pass beneath the gate 80. The gate 80 is cammed upwardly by camming surfaces 18 a with which the single washer 18' is embossed on its upper face and near its leading edge (see FIGURE 11) as the single washer 18' is displaced by the shuttle 70, so as to allow the single washer 18' to pass beneath the gate 80. As cammed upwardly, the gate 80 engages the leading edges of the overlying washers 18 in the stack (see FIGURE 11) so as to restrain the overlying washers 18 against being displaced with the single washer 18'. After the single washer 18 has passed beneath the gate 80 except for a marginal portion including the trailing edge of the washer 18', the single washer 18' is considered to have been moved to the separated position, and the gate 80 engages camming surfaces 18 b with which the single washer 18 is embossed on its upper face and near its trailing edge (see FIGURE 12) so as to restrain the single washer 18' against being displaced from the separated position as the shuttle 70 next moves from the normal position to the displaced position. Moreover, the machine 10 comprises shuttle-biasing means, shuttle-moving means, and fastener-driving means. The shuttle-biasing means biases the shuttle 70 to the normal position but permits the shuttle 70 to be forcibly moved (against such bias) from the normal position to the displaced position. The shuttle-moving means, which is arranged to be operator-actuated and to be normally deactuated, moves the shuttle 70 forcibly (against such bias) from the normal position to the displaced position when actuated and moves the shuttle 70 as biased by the shuttle-biasing means from the displaced position to the normal position when deactuated. The fastener-driving means is used to drive a screw 16 through the central aperture of the single washer 18' while the single washer 18' is in the separated position and the shuttle 70 is in the displaced position. The shuttle-biasing, shuttle-moving, and fastener-driving means are provided by linking a stand-up screw gun of a type exemplified in Murray U.S. Patent No. 3,960,191, Dewey U.S. Patent No. 4,236,555, and Dewey U.S. Patent No. 4,297,412 to the shuttle 70, via a mechanical linkage, as described below. The disclosures of Murray U.S. Patent No. 3,960,191, Dewey U.S. Patent No. 4,236,555, and Dewey U.S. Patent No. 4,397,412 are incorporated herein by reference. Thus, a tubular nosepiece 100 is welded to the bight 42 of the bracket 40 so as to extend upwardly, and so as to communicate with the central aperture 44 in the bight 42, and is provided at its lower end with an integral collar 102 and with a pair of jaws 104, which extend radially into diametrically opposed apertures 106 in the integral collar 102, and which are biased inwardly in a radial sense by an elastomeric O-ring 108 disposed around the integral collar 102 and seated removably in suitable grooves 110 in the respective jaws 104. Similar jaws biased by such an O-ring are disclosed in Dewey U.S. Patent No. 4,236,555. The jaws 104, which are adapted to be outwardly cammed in a manner to be later described, position a screw 16 in axial alignment with a driving bit to be later described, prevent the screw 16 from dropping through the nosepiece 100 before the screw 16 is driven by the driving bit, but permit the screw 16 to be downwardly ejected as the screw 16 is driven. As shown in FIGURE 4, the nosepiece 100 is provided externally with a J-shaped groove 112, which has a longer, vertical portion 114 leading to the upper end of the nosepiece 100, a curved, transitional portion 116, and a shorter, vertical portion 118. The curved, transitional portion 116 leads to the lower end of the longer, vertical portion 114 and to a midsection of the shorter, vertical portion 118. As shown in FIGURES 3 and 4 and elsewhere, a tubular element 120 is telescoped over the tubular nosepiece 100. A horseshoe-shaped bracket 122, which partly surrounds the tubular element 120, is welded to the tubular element 120. The bracket 122 receives a machine screw 124 having a threaded shank 124 a which passes through an aperture 122 a , in the bracket 122, and through an axially aligned, threaded aperture (not shown) in a lower end portion of the tubular element 120, and which extends into the groove 112 when the tubular element 120 is telescoped over the tubular nosepiece 100. When the tubular element 120 and the tubular nosepiece 100 are assembled, the threaded shank 124 a of the machine screw 124 is manipulated down the longer vertical portion 114, through the curved transitional portion 116, and into the shorter vertical portion 118, which allows a limited range of vertical movement of the tubular element 120 relative to the tubular nosepiece 100. A coiled spring 126 is fitted into the tubular element 120 so as to bear at its lower end, via an annular washer 128 fixed to the lower end of the coiled spring 126, against the upper end of the tubular nosepiece 100, and so as to bear at its upper end against an annular stop (not shown) within the tubular element 120, thereby to bias the tubular element 120 upwardly in the limited range of vertical movement of the tubular element 120 relative to the tubular nosepiece 100. The threaded shank 124a of the machine screw 124 engages the annular washer 128 at the lower end of the coiled spring 126 so as to restrain the coiled spring 126 against being ejected from the tubular element 120 when the tubular element 120 and the tubular nosepiece 100 are disassembled. As shown in FIGURES 1 and 15, a tubular element 130 is telescoped over the tubular element 120. The tubular element 130 is provided with a wide vertical slot 132. A fitment 134, which is attached by machine screws to an upper end portion of the tubular element 120, extends outwardly through the slot 132, which provides a limited range of vertical movement of the tubular element 130 relative to the tubular element 120. A coiled spring 136 is fitted into the tubular element 130 so as to bear at its lower end against the tubular element 120, and so as to bear at its upper end against an annular stop (not shown) which is mounted within the tubular element 130 by machine screws 138 mounted in threaded apertures (not shown) in the tubular element 130, thereby to bias the tubular element 130 upwardly in the limited range of vertical movement of the tubular element 130 relative to the tubular element 120. A bolt 150, which is threaded through the fitment 134, serves as a pivot for a latching element 152, which can be selectively pivoted between an operative position (see FIGURES 16 and 17) wherein the latching element 152 engages a fixed stop 154 welded to the tubular element 130, so as to prevent upward movement of the tubular element 130 relative to the tubular element 120, and an inoperative position (see FIGURE 15) wherein such movement is permitted by the latching element 152. A pintle 156, which extends laterally from the fitment 134, limits pivotal movement of the latching element 152. A trigger-actuatable, electrically powered screw gun 160 is mounted in a known manner to the upper end of the tubular element 130. The screw gun 160 comprises an elongate, rod-like driver 162 carrying a driving bit 164, which can be removably attached to the driver 162 (see FIGURE 10) at its lower end. The driving bit 164 has a downwardly opening, hexagonal socket 166, which is adapted to drive a screw 16 (see FIGURE 10) fed in a manner to be next described, when the screw gun 160 is actuated with the socket 166 engaged with the head of the screw 16. The socket 166 can be so engaged only when the tubular element 130 has been moved forcibly downward along the tubular element 120 and the tubular element 120 has been moved forcibly downward along the tubular nosepiece 100. The driving bit 164 is adapted to cam the jaws 104 outwardly when moved downwardly with the tubular elements 120, 130. The coiled springs 126, 136, are selected to have spring characteristics enabling the tubular element 120 to be so moved only after the tubular element 130 has been so moved so as to cause the coiled spring 126 to be fully compressed, or nearly so. A screw-feeding tube 180 is mounted removably to the tubular element 120. A fitment 182, which is welded to the tube 180, can be removably mounted to the fitment 134 (which, as described above, is attached to an upper end portion of the tubular element 120) by the bolt 150, which receives a wing nut 184, as shown in FIGURES 15, 16, and 17. A screw-deflecting slide 186, which is mounted rigidly to the lower end of the tube 180, has a pair of ears 188, which fit into downwardly opening recesses 190 in distal ends of the horseshoe-shaped bracket 122 (see FIGURE 7) when the fitment 182 is mounted to the fitment 134, so as to mount the tube 180 to the tubular element 120. Where the tubular element 120 confronts the slide 186, the tubular element 120 is provided with a wide, vertical slot 192 (see FIGURE 6 and 8) providing sufficient clearance for a screw 16 fed through the tube 180. Where the vertical slot 192 confronts the tubular nosepiece 100 when the tubular element 120 is in its uppermost position relative to the tubular nosepiece 100, the tubular nosepiece 100 is provided with a narrow, vertical slot 194 having an enlarged upper end 196 and providing sufficient clearance for a screw 16 fed through the tube 180 when the tubular element 120 is in such position, so long as the head of the screw 16 is upward as the screw 16 is fed through the tube 180. The enlarged upper end 196 of the slot 194 provides sufficient clearance for the head and integral washer of the screw 16 whereas the remaining portions of the slot 194 provide sufficient clearance only for the threaded shank of the screw 16. The slide 186 has, on each side, camming surfaces 198 (see FIGURE 6) which cooperate with the integral washer of the screw 16 so as to deflect the head and integral washer of the screw 16 through the slot 192 into the enlarged upper end 196 of the slot 194. FIGURE 6 shows, in phantom lines, a screw 16 after the screw 16 has passed through the slots 192, 194. When the tubular element 120 is not in its uppermost position relative to the tubular nosepiece 100, the vertical slot 192 does not confront the vertical slot 194, and a screw 16 at the vertical slot 192 cannot enter the vertical slot 194. As described so far, except for the welded connection of the tubular nosepiece 100 to the bight of the bracket 40, and except for certain features to be later described, the tubular nosepiece 100, the tubular element 120, the tubular element 130, the screw gun 160, the feed tube 180, and associated components described above are similar to similarly functioning components of stand-up screw guns sold heretofore by ITW-Buildex (Illinois Tool Works Inc.), Itasca, Illinois, under its ACCUDRIVE XL trademark. Since such components and their functions are known to those skilled in the art, further description of such components and their functions is not necessary, except as given below. A crosspiece 200, which is welded to the slide 186 so as to extend over the side plates 32, 34, has a pivot pin 202 with an enlarged head at each end of the crosspiece 200. The pivot pins 202 extend beyond the plates 32, 34, on each side of the base 30. A driving link 204 is connected at its upper end 206 to the pivot pin 202 at each end of the crosspiece 200. Each driving link 204 is connected at its lower end 208, via an integral pin 210, to a rear toggle link 212 at a location between the ends of the rear toggle link 212. The pivot pin 210 is closer to the upper end 214 of the rear toggle link 212 and further from its lower end 216. Each rear toggle link 212 is connected at its lower end 216, via a pivot pin 218 extending through a suitable aperture in a respective one of the side plates 32, 34, to a respective end of the brace 38. Each rear toggle link 212 is connected at its upper end 214, via an integral pin 220, to a front toggle link 222 at the upper end 224 of the front toggle link 222. Each front toggle link 222 is connected at its lower end 226, via a pivot pin 228, to the respective ends of a brace 230, which overlies a front end portion of the shuttle 70 and is assembled thereto by machine screws. Each pivot pin 228 extends through a longitudinal slot 232 in a respective one of the side plates 32, 34. Thus, when the screw-feeding tube 180 and the screw-deflecting slide 186 (which is mounted rigidly thereto) are moved downwardly, the mechanical linkage comprising the driving links 204, the rear toggle links 212, and the front toggle links 222 causes the shuttle 70 to move toward the displaced position. The V-shaped cutout 58 in the rear wall 54 provides clearance for the crosspiece 200, which has a rearwardly extending portion, as shown. Also, when the tube 180 and the slide 186 are moved upwardly, the same linkage causes the shuttle 70 to move toward the normal position. Moreover, because the coiled spring 136 biases the tubular element 130 upwardly along the tubular element 120, the coiled spring 136 also biases the shuttle 70 toward the normal position. The tubular element 130 is threaded at its lower end, as shown, where it is provided with a threaded collar 240 which can be manually rotated on the lower end of the tubular element 130. An O-ring 242 iS mounted around the threaded collar 240 so as to bias a ball (not shown) into releasable holding engagement with a respective one of four axial grooves spaced regularly around the collar 240. The screw-feeding tube 180 is provided with a fixed stop 244, against which the threaded collar 240 bears when rotated downwardly on the lower end of the tubular element 120. Rotation of the threaded collar 240 on the tubular element 130, as limited by the fixed stop 244, adjusts the maximum downward extension of the driving bit 164. As shown in FIGURES 18 and 19, the stack of washers 18 may be conveniently packaged in a container 260. Such a container is described in our co-pending divisional application filed on the same date and entitled "Stackable washer". As shown in FIGURE 19, the stack may be conveniently left in the container 260, after the cover 262 has been removed, when the stack is inserted manually into the washer-receiving chute 50, which provides sufficient clearance for such a container having thin walls. When the stack is left in the container 260, the container 260 rests on edge portions of the shuttle 70, so as to span the recessed rear portion of the shuttle 70, when the shuttle 70 is in the displaced position. Otherwise, as shown, the container 260 is seated across the shuttle 70. The top wall 264 and the side wall 268 are provided with a vertical slot 274, which is disposed so as to expose the notches 64 in the washers 18 in the stack. The top wall 264 and the side wall 270 have a vertical slot 276, which is disposed so as to expose the notches 66 in the washers 18 in the stack. Thus, the slot 274 permits the rib 60 to fit through the slot 274 into the notches 64 in the washers 18 in the stack and the slot 276 permits the rib 62 to fit through the slot 276 into the notches 66 in the washers 18 in the stack, thereby to restrain the washers 18 in the stack against cascading from the stack S if the machine 10 including the chute 50 is tipped so as to tip the stack. The front wall 266 has an inverted, V-shaped cutout 278, which facilitates handling the stack in the container 260, after the cover 262 has been removed, as when the stack S is to be manually inserted into the chute 50. Similarly, the front wall may have an inverted, V-shaped cutout (not shown) at its lower edge. A preferred embodiment for washers used in the machine of the present invention are shown in FIGURES 20 through 23. Such washers are disclosed in our co-pending divisional application filed on the same date and entitled "Stackable washer".

Claims: A washer dispensing and fastener-driving machine for use with stackable roofing washers (18) having central apertures (20) and for use in fastening roofing material, such as a blanket of roofing insulation or a roofing membrane, to an underlayment, such as a wooden roof or a corrugated metal roof, by fasteners having heads with one washer between the head of each fastener and material, comprises: a base (30); a chute (50), which is supported by the base; a shuttle (70), which is mounted on the base (30) for horizontal movement between a normal position and a displaced position, which is adapted to engage a single washer from the stack of roofing washers (18) received by the chute (50) when the shuttle is in the displaced position, which is adapted to displace the single washer from the stack to a separated position by positive engagement of the shuttle (70) with the single washer (18) as the shuttle (70) moves from the displaced position to the normal position, and which is adapted to release the single washer (18) in the separated position as the shuttle next moves from the normal position to the displaced position; fastener-driving means (160) adapted to be operator-actuated for driving a fastener (16) through the central aperture (20) of the single washer (18) while the single washer is in the separated position and the shuttle (70) is in the displaced position; characterised in that the machine further comprises: a washer-restraining means (80) movable between an upper and a lower position, biased to the lower position, and arranged such that in the upper position, only the single washer (18) engaged in the shuttle (70) may pass below the washer-restraining means (80), and in the lower position, none of the washers (18) in the stack (S) or a washer (18) in the separated position can pass below the washer-restraining means (80); a shuttle biasing means (126) arranged to bias the shuttle (70) to the normal position but allow the shuttle (70) to be forcibly moved to the displaced position; and a shuttle-moving means (220, 204, 212, 222) arranged to be operator-actuated and to be normally deactuated for moving the shuttle forcibly from the normal position to the displaced position when actuated and for moving the shuttle (70) as biased by the shuttle-biasing means from the displaced position to the normal position when deactuated; and, in that the chute is adapted to receive a stack of roofing washers (18) to be individually dispensed by the machine. A washer-dispensing and fastener-driving machine according to claim 1, for use with stackable roofing washers (18) being embossed to form camming surfaces on peripheral areas of one face of each such washer and being stacked so that the face formed with camming surfaces on each washer is the upper face, wherein the washer-restraining means comprises a gate (80), which is mounted on the base (30) for vertical movement toward and away from a lowermost position, which is biased toward the lowermost position, which in the lowermost position provides sufficient clearance for all or substantially all of a single washer (18) being displaced by the shuttle (70) from the stack (S) to the separated position to pass beneath the gate (80) but insufficient clearance for any overlying washer in the stack also to pass beneath the gate (80) with a single washer (18), which is cammed upwardly by camming surfaces on the upper face of the single washer (18) as the single washer is displaced by the shuttle so as to allow the single washer to pass beneath the gate (80), and which engages camming surfaces on the upper face of the single washer so as to restrain the single washer (18) against being displaced from the separated position as the shuttle next moves from the normal position to the displaced position. A washer-dispensing and fastener-driving machine according to claim 1 or 2 for use with stackable roofing washers having a periphery, and a central aperture (20) adapted to receive a fastener, one or more notches (64, 66) in its periphery, the or each notch (64, 66) adapting the washer (18) and a like overlying and underlying washer in a stack to fit into a washer stack-receiving chute (50) of a washer-dispensing machine, the chute being provided with a rib (60, 62) corresponding to the or each notch (64, 66) to restrain washers in a stack received by the chute (50) against cascading from the stack if said chute (50) is tipped. A washer-dispensing and fastener-driving machine according to claim 3, wherein the rib (60, 62) is located such that the chute (50) is shaped assymetrically to ensure that camming surfaces formed on the one face of each washer (18) face upwards when the washers (18) are received by the chute (50). A washer-dispensing and fastener-driving machine according to any one of the preceding claims, in which the stack (S) of washers (18) are packaged in a container (260) having lateral walls (266, 270), which have at least one slot (274, 276) exposing the or each notch of the washers (18) in the container.

Inventors: BEACH JOHN R, HASAN SYED RIAZ-UI, HINDMAN CRAIG ALLAN, NOREN DONALD W, SANTI ERNEST SCOTT, BEACH, JOHN R., HASAN, SYED RIAZ-UI, HINDMAN, CRAIG ALLAN, NOREN, DONALD W., SANTI, ERNEST SCOTT
Applicants: ILLINOIS TOOL WORKS, ILLINOIS TOOL WORKS INC.
Application year: 1990
Main classification: B23P19
IPC codes: E04D5, F16B43, E04D3, E04D15, B25B23