Roofing washer-dispensing and fastener-driving machine

In a washer-dispensing and fastener-driving machine for dispensing stackable roofing washers individually from a stack of similar washers and for driving fasteners through the washers for fastening at least one layer of roofing material to an underlayment, the combination comprising:

• (a) a base;
• (b) means including a shuttle mounted movably to the base for displacing a lowermost washer from the stack and for moving the lowermost washer lengthwise to a separated position;
• (c) means including a screw gun for driving a fastener rotatably and downwardly through the displaced washer in the separated position;
• and
• (d) means including an element engageable with the displaced washer for preventing the displaced washer from rotating when a fastener is being driven through the displaced washer;
• wherein the machine is adaptable for dispensing stackable roofing washers of either of two types, namely generally square washers and generally oblong washers, each generally oblong washer having two relatively long sides and two relatively short ends;
• wherein the element engageable with the displaced washer is adjustable upwardly to an inoperative position, in which said element is not engageable with a washer of either type in the separated position, and downwardly to an operative position, in which said element is engageable with one of the relatively long sides of such a generally oblong washer in the separated position;
• wherein the element engageable with the displaced washer includes a rod having a lower, straight portion extending in a generally vertical direction and an upper, hooked portion, the lower portion being mounted to the base so as to be upwardly and downwardly movable and being biased downwardly to the operative position, the upper portion being manipulatable in the operative position to hook over a portion of the base.