Combination lock with arrangement for defeating automatic dialer

For use in a combination lock, said combination lock including a rotary dial, a shaft extending from and rotatable with said dial, a cam wheel mounted on the free end of said shaft and a key for keying said cam wheel to said shaft whereby said key and said cam wheel rotate with the rotation of said shaft;

• a means for defeating a high speed automatic dialer, comprising:
• a ring member having an outer surface and an inner surface;
• a rotating member, having an outer peripheral surface, and being rotatably mounted in said ring member;
• said rotating member including a central elongated slot;
• said key extending into said central elongated slot;
• said rotating member further including at least one peripheral slot extending from said peripheral surface into the body of said rotating member;
• a ball bearing carried in said peripheral slot;
• the inner surface of said ring member being substantially identical to the outer peripheral surface of said rotating member, the inner surface of said ring member including additionally at least one cut-out;
• whereby, when said rotating member is driven to rotate at a high speed by said automatic dialer, said ball bearing will be driven by centrifugal force into said cut-out whereby to prevent further rotation of said dial to thereby block said lock.