Patent GB-1440414-A (GB)
Title: Panel sawing machine
IPC: B23Q11/00
Filed: 1974-10-16
Abstract: 1440414 Panel sawing machines KARL M REICH MASCHINENFABRIK GmbH 16 Oct 1974 [2 Nov 1973] 44822/74 Heading B5L Relates to a panel sawing machine, for separating wooden or plastics panels, comprising a frame 1 provided on a base (3) thereof with panel rest rollers (51), a substantially vertical grid 4 supported on the frame and provided with horizontal panel support ribs 5, a substantially vertical guide bar 12 roller-supported on the frame for horizontal traverse over the grid, a saw carriage 15 traversable along and adjustably positionable on the guide bar, and a circular saw supported on the carriage for movement towards and away from the grid, wherein, in use, for effecting horizontal cuts, the saw carriage is locked to the guide bar and the latter is traversed horizontally over the grid, and for effecting vertical cuts the guide bar is stationed and the saw carriage is traversed therealong. In such a machine, means are provided whereby, on locking of the saw carriage to the guide bar in preparation for effecting horizontal cuts, the vertical relationship of the saw blade and the support ribs 5 is sensed and when said relationship is such that the saw blade confronts, and would therefore cut into, one of the support ribs, the grid 4 is automatically raised a predetermined distance to avoid said confrontation. The carriage may be locked to the guide bar pneumatically, electrically or, as shown, manualmechanically, and the support grid may be moved mechanically, electromagnetically or, as shown, pneumatically. As shown, the carriage locking means comprises friction-padded jaws 20 pivoted on the carriage and actuable to grip a plate 14 of the guide bar by a handle and toggle device 23-25. The jaws are held in their clamping position by a retaining spring 26. The guide bar 12 carries a control strip 46 comprising slots 48 and, pitched to correspond with the support ribs 5, inter-slot parts 47. The carriage carries a switching device comprising spring-biased switch cams 31, 33, the cam 33 being rightwardly urged by a spring 36 and the two cams being separatingly urged by a spring 39. On carriage-locking actuation of the handle 25, a handle-actuated screw 27 leftwardly moves the cam 31 to actuate a switch 42, and the cam 33 is or is not moved leftwardly to actuate a switch 43 depending on whether a sensing stud 35 of the cam 33 is opposite a slot 48 or an inter-slot part 47 of the control strip 46. The grid 4 is upwardly movable by an air cylinder 8 which acts via a lever 10 and is energized via an electro-pneumatic valve 45 in circuit with the switches 42, 43. A saw (16) is pivotably mounted on the carriage 15 for movement between vertical and horizontal sawing positions, and is movable with respect to the carriage and towards and away from the grid 4 by an air cylinder 18. In operation, the carriage is positioned on the guide bar 12 to bring the saw into line with either a scale or with a line scribed on a workpiece panel. The locking jaws 20 are applied and, on confrontation of the saw blade and a support rib, the control valve 45 is actuated to energize the cylinder 8 and lift the grid 4. Release of the jaws effects a lowering of the grid to its starting position. In Fig. 7, there is provided (i) a switch 52 actuated on outward movement of the saw by the cylinder 18 and connected in circuit with the electro-pneumatic valve 45 to prevent actuation of the cylinder 8 and lifting of the grid unless the saw is in its cleared position, and (ii) a switch 55 actuated on lifting of the grid to its uppermost position and connected in circuit with a valve 57 controlling the cylinder 18 to prevent movement of the saw towards the grid before said uppermost position of the latter is reached. The valve 57 has a manual control switch 58. Vertical sawing is effected only at certain horizontal positions on the grid where saw blade grooves (59) are provided.