Raspberry pi model B freeze

[Kingsley]

Hi, i am using raspberry pi model B to do a project call ultrasonic range finder. The component include ultrasonic sensor, three digit 7 segment display , led, buzzer, some transistors and resistors. I Crete a loop in my program in order to let the sensor to detect the latest distance and 7 segment display show the latest output. In order to let the 3 digit of the 7 segment display show together, I put a short delay for each digit to show which is 10 mili second. When I run the program, it work perfectly. However after some time, the whole project will freeze and hang at there. For example, three digit output left one digit and nothing happend when I change the distance. To make it function again, I need to re run again the program. However, after some time same thing will happen again. When I change the delay time to become 1 second, if was function well. Why this will happen?

[mikronauts]

It may be the power supply you are using. Does the whole Pi crash when it freezes? Or can you still ssh into it and run commands?