CAM Controlled Automatics

CAM Controlled Automatics

CAM Controlled Automatics - The structure of cam controlled automatic machine tools is discussed below: Each machine tool consists of motion (M), transmitting (T) and operative (O) mechanisms and working member (W).

Transmitting mechanisms have a rotary motion. The main working members and most of the auxiliary members of automatic machine tools execute closed cycles of reciprocating motions. Hence, the operative mechanisms of most working members serve to convert rotary motion into reciprocating motion.

These mechanisms are further complicated by lever or other devices for transmitting motion to the working members. In addition, certain auxiliary working members make rotary motions and, in the majority of cases, indexing motions for changing positions or stations. In these cases, the operative mechanisms are rotary mechanisms for periodic motion, operating on closed rotary cycles.

The covers both the main and auxiliary working members. To enable various particular motion cycles of the working members of automatic machine tools with a mechanical drive to be accomplished without disconnecting the kinematic linkages between the various members themselves and between the members and the transmitting mechanism T,

It will be necessary to incorporate a device (Kc) providing for a cyclic change in the kinematic linkage between the transmitting mechanism T and the working member W in the particular drive of each working member. Changes in the motions of the working member take place during its closed and repeated operating cycle due to this device Kc.

The operative mechanisms of the working members of automatic machine tools can be divided into two groups:

(1) Operative mechanisms which incorporate Kc, a device for a cyclic change in the kinematic linkage between the transmitting mechanism T and the working member W. These are cyclic operative mechanisms 0 c of which the most widely used are cam mechanisms.

2) Operative mechanisms which do not incorporate such a device Kc for a cyclic change is noncyclic mechanisms on of which the most commonly used are the motion screw and nut mechanism.