A device on machines for joining boards by means of duebel for feeding undhalten the duebel between the boards to be joined

摘要

7166. Tracy, P., and Dingwall, T. E. March 23. Dowelling.-In a dowelling-machine of the type wherein the resistance applied to cause the dowels to penetrate yields when the penetration has been effected, the boards so joined are arranged to be moved along the bed of the machine to leave room for the insertion of another board. The travel of the boards is produced by a reciprocating fence 3, Fig. 1, worked by a pin 4 on a wheel 5, which pin also works a slide 19 in a magazine 18 of dowels, which are raised one at a time to the position shown. Any number of such magazines may be used. As the board 9 advances, it rocks the slide 19 clear of a supporting catch 23 and allows it to drop ready to bring up another dowel. Resistance to the pressure of the board 9 is provided by a fence 10 in front of the board 8 and connected to a chain 11 gearing with wheels 12, 13. The wheel 12 is braked at a suitable part of the stroke by the action of a cam on the wheel 5 and levers 17. When the wheel 12 is released, both boards 8, 9 are traversed together to the limit of the travel of the fence 3, which then recedes, leaving space for another board to be put in. This process may be repeated until the fence 10 has travelled to the extreme right hand side of the machine. Pressure is applied to the boards by a weighted bar 30 worked from a treadle 28, and this pressure may if desired be arranged to hold the board 8 during penetration, the fence 10 and braking arrangement being dispensed with. Or the inertia of the wheel 12 may be relied on for the same purpose. Fig. 2 shows the magazine for holding the dowels and the groove-ended slide 19. In a machine modified for joining vertically-placed boards, the slide feeding the dowels works horizontally and is magnetized to hold the dowel on its end.