Pin Motion Interface (Pmi) - Brunswick StringPin Service Manual

Pin Motion Interface (PMI)

The Pin Motion Interface is the final main frame component a string passes through before being routed
to the setting platform and pin. The Pin Motion Interface serves two main functions for the pinsetter.
1. Detects when a pin has been knocked over.
2. Controls whether the pin will be lowered to the pindeck when the string wagon
moves toward the front of the machine.
When a pin is knocked over, the pulling of the string causes a pulley and gear, referred to as a string
roller and string gear, to rotate. If the string pulls with enough force, a magnet, attached to the string
gear through a friction clutch, rotates to actuate a reed type switch. A pinfall sensitivity adjustment on
the Pin Motion Interface determines the amount of string pull force needed, by controlling the distance
the magnet must rotate to actuate the switch.
The second function of the Pin Motion Interface controls whether the pin is allowed to lower to the
pindeck. In normal operation the string moves freely though the PMI allowing the pin to lower to
the pindeck. Energizing the brake solenoid inside the PMI causes a string brake to pinch the string
prohibiting it from passing through the PMI. Refer to Figure 2-19.
Each of the ten PMI assemblies consist of the following components:
• Solenoid to operate the string brake
• String Brake
• Pinfall Switch
• Magnet
• Friction Clutch Gear
• String Roller
• Pinfall Sensitivity Adjustment
(12)
MAGNET POSITION
AFTER PINFALL
(4)
PINFALL
SWITCH
(10)
ENDING POSITION
OF MAGNET
Figure 2-19. Pin Motion Interface Components
(1) BRAKE SOLENOID
(4) PINFALL SWITCH
(7) STRING ROLLER
(10) ENDING POSITION FOR
MAGNET
Section 2: Overview
(6)
PINFALL
SENSITIVITY
ADJUSTMENT
(3)
MAGNET POSITION
BEFORE PINFALL
(9)
STARTING POSITION
FOR MAGNET
(7)
STRING
(11)
ROLLER
STRING
(2) STRING BRAKE
(5) MAGNET
(8) FRICTION CLUTCH GEAR
(11) STRING
(6)
PINFALL
SENSITIVITY
ADJUSMENT
(5)
MAGNET
(7)
STRING
ROLLER
(11)
STRING
(3) MAGNET POSITION BEFORE PINFALL
(6) PINFALL SENSITIVITY ADJUSTMENT
(9) STARTING POSITION FOR MAGNET
(12) MAGNET POSITION AFTER PINFALL
(4)
PINFALL
SWITCH
(1)
BRAKE
SOLENOID
(2)
STRING
BRAKE
(8)
FRICTION
CLUTCH
GEAR
2-19