Tool changing mechanism

DETAILED DESCRIPTION With the foregoing object in view, the present invention provides a tool changing mechanism to be incorporated into a plate drilling machine having a spindle, comprising: a tool magazine including a plurality of tool posts, capable of being moved to bring one of the tool posts into alignment with the spindle; a locating mechanism for locating the tool magazine so that one of the tool posts is brought into alignment with the spindle; and a tool pressing mechanism fixedly disposed opposite to the spindle with respect to the tool magazine at a tool changing position provided in a range in which the spindle is movable, the tool pressing mechanism being operable to press one of the tool posts aligned with the spindle toward the spindle for a tool changing operation.
Since only the single tool pressing mechanism is fixedly disposed opposite to the spindle, the number of the component parts of the tool changing mechanism is far less than that of the component parts of the known tool changing mechanism, and the tool changing mechanism needs a controller of a simple configuration.
If pneumatic cylinder actuators are employed as the tool pressing mechanism, the number of the pneumatic cylinder actuators is equal to that of the spindles and the tool pressing mechanism consumes only a small amount of compressed air.
Since the tool pressing mechanism is not held on a movable work table, the movable work table can be moved at increased speed.
Since the tool pressing mechanism is fixedly held in place and is separate from the tool magazine, the dimensions of the tool pressing mechanism are not dependent on the size of the tool posts, and the tool pressing mechanism may be an inexpensive general-purpose cylinder actuator.
The above and other objects, features and advantages of the present invention will become more apparent from the following description taken in connection with the accompanying drawings.