Method and system for detecting brake wear in a metal forming machine

In a metal forming machine having a ram operable by a rotative drive system and a brake for stopping the ram, the combination comprising:

• means for sensing the rotation of the drive system,
• means responsive to said sensing means for determining the amount of rotation of the drive system from the time of energization of the brake and the time of stopping of the ram,
• means for comparing the determined amount of rotation of the drive system with a predetermined magnitude,
• alarm means for being operated if the determined amount of rotation of the drive system exceeds the predetermined magnitude, and
• means for automatically preventing further operation of the work producing member if the determined amount of rotation of the drive system exceeds the predetermined magnitude.

In a metal forming machine having a ram operable by a rotative drive system and a brake for stopping the ram, the combination comprising:

• a sensor for sensing rotative movement of structure associated with a gear in the drive system and for generating electrical signals in response thereto,
• means responsive to said electrical signals for determining the amount of rotation of the drive system from the time of energization of the brake and the time of stopping of the ram,
• means for comparing the determined amount of rotation of the drive system with a predetermined magnitude, and
• alarm means for being operated if the determined amount of rotation of the drive system exceeds the predetermined magnitude.

In a press machine having a ram operable by a rotative drive and a brake operable to stop the ram, the combination comprising:

• timing means responsive to electrical signals representative of the amount of rotation of the drive,
• means responsive to a first angular position of the drive for directing a first portion of said electrical signals to said timing means,
• self-check circuitry for preventing further rotation of the drive if a predetermined number of the first portion of said electrical signals are not received by said timing means,
• means responsive to the energization of the brake for directing a second portion of said electrical signals to said timing means until the rotation of the drive is stopped;
• and
• means for preventing further rotation of the drive if the second portion of said electrical signal exceeds a predetermined magnitude.

A method of detecting brake wear in a metal forming machine having a ram operable by a rotative drive and having a brake for stopping the ram comprising:

• sensing the amount of rotation of the drive,
• determining the amount of rotation of the drive from the time of energization of the brake and the time of stopping of the ram by the brake,
• comparing the determined amount of rotation of the drive with a predetermined magnitude, and
• generating an alarm if the determined amount of rotation exceeds the predetermined magnitude.