Dickey-john Corporation

John T Knepler

Wesley J Bachman

A monitor is provided for a field planting machine having a plurality of planting units and a plurality of seed sensors respectively associated with the planting units for producing seed signals in response to the dispensing of seeds thereby. The monitor comprises a plurality of sensor circuits coupled in series circuit, one of the sensor circuits being coupled intermediate each of the sensors and a common signal line. These sensor circuits and the associated sensors are sequentially selectable for causing a first condition on the common signal line in response to production of seed signals at or above a predetermined rate and a second condition on the common signal line in response to the non-production of seed signals at or above the predetermined rate.

Grain drill monitor

A seed sensor for sensing seeds flowing along a path is provided with an electromagnetic transducer having a movable diaphragm. An arm is secured to a generally peripheral portion of the diaphragm and extends into the seed flow path to be struck at random by the seeds. The arm has a portion operatively engageable with a mid portion of the diaphragm and functions as a mechanical amplifier to actuate the diaphragm when struck by the seeds for producing usable output signals.

Seed sensor

An air pressure monitor includes an electro-mechanical sensor comprising a flexible diaphragm whose deflection is proportional to the air pressure applied thereto, and a variable inductor including a coil and a movable core inside of the coil, the movable core being attached to the flexible diaphragm for movement in response to the deflection thereof to adjust the inductance of the coil in proportion to the air pressure applied to the diaphragm. The monitor further comprises electrical circuits including a first oscillator circuit including the coil for producing a pressure signal at a frequency proportional to the pressure in response to the inductance of the coil, and a second oscillator circuit for producing a reference signal at a frequency corresponding to the frequency produced by the first oscillator when the pressure is substantially zero. Mixer and filter circuits are provided, connected to the two oscillator circuits for providing a signal whose frequency is proportional to the difference in frequencies between the pressure and reference signals and a Schmitt trigger and divider are connected in series from the filter circuit for producing a chain of digital pulses at a frequency proportional to that of the difference signal. An adjustable gate generator is provided for producing a gate signal having a predetermined period, such that the number of digital pulses produced at the output of the divider during the predetermined period comprises a digital signal corresponding to a measurement in predetermined, fixed units of the pressure at the diaphragm.

Air pressure monitor

A seed level sensor for automatic seed planting apparatus is provided with connecting plugs for connecting the seed level sensor to electrical leads presently existing between a seed dispensing sensor and a seed planter monitor. The seed level sensor includes a switching device connected in one of the lines of the electrical leads between the seed dispensing sensor and the seed planter monitor and which interrupts the operation of the seed dispensing sensor when the level of seeds within the hopper is below a predetermined level. An indicator associated with the seed planter monitor is energized for a given period of time when seeds are below the predetermined level, to alert the operator that a low seed level exists in the hopper.

Growing community of inventors

Chatham, IL, United States of America

John T Knepler