Patent GB-391539-A (GB)
Title: Feed mechanism for metal milling or other machines
IPC: B23C9/00
Filed: 1932-01-01
Abstract: 391,539. Feed mechanism for milling &c. machines. HOPPE, O., 27, Kirchstrasse, Rorschach, Switzerland. Jan. 1, 1932, No. 109. [Class 83 (iii).] In feed mechanism for reciprocating the table of a milling or like machine a control rod is provided which is moved by hand, or mechanically by dogs on the table, so as to operate a slide controlling the supply of fluid pressure to a piston connected to the rod, whereby the rod is moved further to operate clutches controlling the driving mechanism of the table. The machine table 11 is reciprocated by a screw 10a and nut 10 rotated by gearing 8 from a gear 7 which is connected by a clutch 7a either directly to a clutch 6 on a shaft 5 for a high speed drive or to a gear 4 for a low speed drive. The gear 4 is loose on the shaft 5 but is driven therefrom at one of two speeds through a back shaft 45 and a slidable pair of gears 3. The shaft 5 is rotated in one or other direction by a bevel gear 5a engaging bevel gears 2a loose on the driving shaft 2 but alternatively connected thereto by a slidable clutch 12. The clutches 7a, 12 are operated by levers 13, 14 respectively which are controlled by cam slots 13a, 14a in a disc 15. A pinion 15a in the disc 15 engages a rack on the vertically slidable control rod 16 which also engages a pinion on an operating handle 17 and a pinion 24 on a shaft 24a to which a disc 30 is secured. A piston 18 is mounted on the lower end of the rod 16, the supply of pneumatic or hydraulic fluid to the cylinder 19 being controlled in direction by a slidable valve 20 and being admitted or shut off by a slidable valve 21. The operating lever 25 for the reversing valve 20 is frictionally secured to the shaft 24a and the lever 31 for the valve 21 carries a roller 31a resting on the disc 30 which has notches 30a in its periphery for receiving the roller. In operation, to move the table 11 slowly to the left in the Figure, the gear pair 3 is moved to give the required speed of slow traverse and the lever 17 is then raised by hand to cause the roller 31a to be lifted out of the " O " notch in the disc 30. During this movement of the disc 30 the reversing valve 20 lies against the end of its valve chamber, and the lever 25 slips on its shaft 24a. This admits fluid below the piston 18, which then acts as a servo-motor and moves the rod 16 upwards, thereby engaging the clutch 12 with the pinion 2a. When the roller drops into the " Av " notch of the disc 30, fluid is cut off from the piston 18 and the table continues to travel until a cam 41 or 41a thereon depresses the rod 16 to return it to the " O " position. For movement of the table in the opposite direction the rod 16 is moved downwards from the " O " position, the reversing valve 20 then being moved by the lever 25 to admit fluid above the piston 18, and for movement in either direction at a higher speed the lever 17 is moved beyond the " Av " or " Ar " positions, the roller 31a then coming to rest in the " Ev " or " Er " notch in the disc 30. For automatic reversal of the table the cam 41 may move the rod 16 so that the roller 31a passes the " O " notch, and intermediate cams 38, 39, 40 may act on the rod 16 to change the speed of the table during a traverse. Either of the notches " Av " or " Ar " may be shrouded by a cam to cause the roller 31a to pass straight to the " Ev " or " Er " notches.