Patent GB-491152-A (GB)
Title: Improvements in or relating to milling machine-tools
IPC: B23C9/00
Filed: 1937-02-26
Abstract: 491,152. Milling - machines. BROWN & SHARPE MANUFACTURING CO. Feb. 26, 1937, No. 5855. Convention date, May 7, 1936. [Class 83 (iii)] A milling-machine has a work-supporting table, a longitudinally movable support therefor, and driving connections for controlling the rate and direction of movement of the table and support comprising a prime mover, a transmission train for moving the table relatively to the support, another transmission train for moving the support, and separate control devices for each train to give starting, stopping and reverse, and a single control element which enables the table transmission train to be driven either directly from the prime mover or through the support transmission train. The machine comprises a main column 20, Fig. 1, on which a cutter spindle 22 is rotatably mounted. The machine is also provided with a work-supporting table 24 mounted to slide on ways 26 formed on a swivel mounting 28 which forms part of a saddle 30 which is mounted for transverse movement on ways 32 carried on the knee. The knee unit is built up of three relatively movable supports comprising a vertically movable knee member 34 arranged to slide in vertical ways formed on the front side of the column 20, and adjustably supported by the usual telescoping screw 36, and a swivel knee member 38 which carries the saddle ways 32 and is arranged to swing about a transverse axis 40. The swivel knee member 38 is in turn carried on a knee rail 42 which is mounted on longitudinally extending ways 44 formed on the vertically adjustable knee member 34 to provide for longitudinal reciprocating movement of the entire assembly. The work table 24 derives its movements from a feed screw 46, Fig. 2, driven through a reversing clutch 52 which may be operated by hand or by adjustable stops carried by the table. A further hand-controlled clutch 86 enables the screw to be connected for table operation or to be disconnected when the table feed is not required. The reversing bevels 54, 56 are driven from a vertical shaft 60 which is driven in turn from a cross-shaft 66 through bevel gearing connected to a bracket 70, Fig. 6, which permits all the possible movements of the table described above without affecting the drive ; the shaft 66 is driven from a longitudinal drive shaft 74. The knee support 42, Fig. 2, is moved by a feed screw 110 which is driven together with the shaft 74 by gearing arranged in a gear-box 120 and driven from a shaft 122, termed the prime mover, which may be driven from a source of power through further conventional rate-charging mechanism. In the gear-box 120, Fig. 7, (developed section oh line 7-7, ;Fig. 3), the clutch sleeve 124 which drives the feed screw 110 is adapted to be driven in forward or reverse directions by gearing from the prime mover 122, and the clutch sleeve may be moved to obtain these results or to stop the drive to the screw by a hand-control 152, Fig. 2, or from the movements of the knee support through a slidable control rod 154 carrying adjustable dogs 156. A gear wheel 164, Fig. 7, slidable on the end of the shaft 74 by means of a hand-control knob 174 enables the shaft 74 to be driven directly from the prime mover 122 through the gears 144 and 136, or in series with the knee support drive by connection with the gear 134 on the shaft 110. For an extremely rapid or extremely slow operation of the table the table transmission train is connected in series with the knee support clutch 124 and the table feed screw is connected to drive the table, the speed of the table is then the resultant of the combined driving rates of the table and the knee support. The machine is also adapted for spiral or spiral taper milling work 180, Fig. 1, by using a spiral head 102 bolted to the table 24 and disconnecting, by means of the clutch 36, the table from the feed screw 46, all the necessary movement being obtained from the knee support feed gear and from the gear 104 driven by the feed screw 46.