Ratchet Driving Mechansim

Abstract

A mechanism for converting intermittent electrical current into a driving force to produce rotary mechanical motion in accurately controlled amounts, thus making it possible to turn an attached wheel the desired fraction of a single revolution by controlling the number of pulses of electric voltages applied to the device. This is accomplished by using a spring-driven pawl to drive a ratchet wheel and an electromagnetic means of retracting the pawl so that the number of retractions is dependent on the number of pulses of electric voltage applied across the solenoid of the retracting electromagnet.

Description

The present invention relates to a device for turning numbered dial wheels in a counting device similar to those used in a common automobile odometer. By applying a given number of pulses of voltage to this device it is possible to cause a numbered wheel connected to this device and having a common axis to turn a given number of degrees and thereby cause a desired number on the circumference of that dial wheel to appear through a viewing window located in a stationary position such that each number will appear through it, one at a time, in succession, as the dial wheel turns.

Such a device makes it possible to have a counter, mechanically remote from the generator creating the electrical pulses, with a number of dial wheels on a common axis, with each wheel driven by a separate device. This makes it possible to register a number in any column, that is, units, tens, hundreds, thousands, etc., without the wheel representing any other column turning at all.

While it is recognized that there is previous art similar to this claimed invention, such as U.S. Pat. No. 3,307,637, to Stautmeister attention is directed to the fact that in the prior art the driving spring is attached to the lever and there is no means of insuring contact between the pawl and the ratchet wheel at high speeds or in case the device is in any, position except that in which gravity will hold the pawl against the ratchet wheel.

By attaching the driving spring to the pawl and to the frame, contact between the pawl and the ratchet wheel is assured regardless of speed or position.

FIG. 1 shows the device in an inoperative position.

FIG. 2 shows the device with the pawl and lever in a retracted position prior to a driving stroke.

When a voltage is applied across solenoid 10 through terminal 8-a and 8-b for a short duration electromagnet 9 draws lever 6 to it by magnetic force placing tension on spring 4 resulting in pawl 5 and lever 6 attaining the position as illustrated in FIG. 2.

When voltage is then interrupted across terminal 8-a and 8-b and current stops flowing through solenoid 10, thus causing the magnetic attraction for lever 6 to cease, the tension on spring 4 causes pawl 5 to pull ratchet wheel 1 around axis 2 the length of one tooth on the ratchet wheel, the motion stopping with lever 6 and pawl 5 in the position shown in FIG. 1.

When a voltage is again applied across terminals 8-a and 8-b and again interrupted, the cycle described above will be repeated.

Each time the voltage is applied and then interrupted the above described action will cause ratchet wheel 1 to turn the length of one ratchet wheel tooth. Therefore the degrees of turning of ratchet wheel 1 can be determined by the number of times the voltage is applied and interrupted across terminals 8-a and 8-b.

Claims

I claim:

1. A ratchet wheel driving device comprising a ratchet wheel driven by a pawl and lever pivotally connected to each other with said lever pivotally connected to a frame, said pawl being pulled to move the ratchet wheel by a spring connected to said pawl and frame and an electromagnet intermittently retracting said lever and producing tension on said spring.