Patent GB-881006-A (GB)
Title: Work transfer apparatus for a machine tool such as a grinding machine
Inventor: BALSIGER HAROLD EDWARD
IPC: B23Q7/00
Filed: 1958-10-17
Abstract: 881,006. Grinding. LANDIS TOOL CO. Oct. 17, 1958, No. 33151/58. Class 60. Apparatus for transferring workpieces from one position to another, such as transferring a crankshaft 11, Fig. 1 to be ground from a delivery conveyer 95 to a grinding machine 17 and, simultaneously, a workpiece from the machine to a discharge conveyer 97, comprises a carriage 25 adapted to be reciprocated along a track 22, the carriage having a pair of spaced trucks 26, 27, each carrying a vertically reciprocable slide 67, Fig. 3, to which depending hook-carrying arms 87 are pivotally connected by a pair of linkages, the links 78, 82, 86 of each linkage being of unequal lengths, and means 76, 77 for oscillating the links. The trucks 26, 27 are spaced apart by bars 43, 44 and have rollers 29, 36, 38, 40 and 41 engaging the track 22 which is of channelsection and secured to brackets 20 vertically adjustable on spaced supports 18, each support being adjustable towards and away from the machine by a rack and pinion mechanism relatively displacing plates 251, 252 on a base 19. The trucks have vertical guides 63, Fig. 4, cooperating with rollers 64 on the slides 67 which are movable by hydraulic piston-and-cylinder devices 65. The links 78, 82 which are oscillated by piston-and-cylinder devices 76, 77, Fig. 3, are pivoted to the slides 67 and to the arms 86 from the lower end of which depend the arms 87 carrying hooks 90, 91, Fig. 1, adapted to engage the line bearings 12 of the crankshaft, and a hook 93 adapted to engage a crankpin 13, the crankpin 16 being the pin to be ground; the hooks are interchangeable so as to permit positioning the shaft for grinding the other pins 13, 14 or 15. A rack 51, Fig. 2, is secured to the track 22 and engages a gear 57 which is integral with a gear 55 engaging a rack 50 on the carriage and is mounted on a traveller 52 reciprocable on rollers 53 engaging the spacing bars 43, 44 by a piston-and-cylinder device 58, 60; the gears act to move the carriage at a faster rate than the movement of the piston. The movements of the carriage, slides and links are controlled by switches controlling electromagnetic relays operating the solenoids of hydraulic valves supplying fluid to the piston-andcylinder devices 58, 60, 65,'and 76, 77; a valve is provided to effect a cushioning effect as each movement nears completion. In operation, a workpiece is moved step-by-step on the conveyer 95, Fig. 1, to the delivery position where a rail 96 raises the pin 13 so that the pin 16 to be ground is in the lower position. At the completion of a grinding operation, the opening of the clamps on the workpiece in the machine actuates devices 76, 77 to cause the links to swing downwardly until the hooks are beneath the workpieces on the conveyer and in the machine. The slides 67 then rise a short distance under the control of the devices 65 to enable the hooks to engage the workpieces and further upward movement of the slides and the upward swinging of the arms lifts the workpieces clear of the machine and conveyer. Clamps securing the carriage in position are automatically released and the carriage moved to the left, as viewed in Fig. 1, by the device 58, 60 to a position wherein the new workpiece is positioned adjacent the machine and the finished workpiece adjacent the discharge conveyer 98. The slides 67 are then lowered and the arms swing downwardly to position the workpieces in the machine and on the discharge conveyer. Further downward movement of the slide disengages the hooks from the workpieces, the arms then being swung to their upward position and the carriage returned to its initial position. The work clamps are then closed and the grinding cycle recommenced.