ELECTROMAGNETIC METER to the appropriate position with respect to the seeds in the
seed furrow by the tube (3).
BACKGROUND ART As schematically illustrated in FIG. 2, the flow of elec
„ . , ... , . trical current to the meter (10) is selectively provided by a
Various electronic metering devices are known but most $ switching mechanism (12) electrically connected by wires
have limitations that restrict the application of the meter. (13) t0 me meter (io). The switching mechanism (12) could
These limitations include slow cycle times, high power include a pickup coil or magnetic switch mounted adjacent
usage, complicated controls and calibrations, difficulty in a rotating shaft or sprocket with iron or magnetic teeth, or
adapting to existing equipment, excessive wear of surfaces any other structure that will appropriately time the cycling
resulting in erratic flow rates, and complicated structures operation of the meter (10) to deliver a precise small
including springs and seals resulting in high production quantity of material at the appropriate time. An operator
costs and maintenance expenses. control box (14) allows the operator to control and monitor
Those concerned with these and other problems recognize me meter (10) from a remote location such as the tractor cab.
the need for an improved electromagnetic meter. A" optional lift switch (16) may be used to lock the meter
(10) in a closed position when the planter is lifted from the
DISCLOSURE OF THE INVENTION ground while turning around at the end of a row and while
being transported from one field to another.
The present invention provides an electromagnetic meter ^ feffed embodiment of flle ^ (10) is best
including an electrical coil wrth a feiromagneUc core Elec- mustrated m nGS 3.5 ^ meter (10) inclu<ks a housin
uical current flowing through the coil is controUed in a ... ^ ^ tQ ^ ^ battaawal of m*
Predetenmnedcyclebyas^^ 20 ^ h a flow
housing has a material outlet and a bracket is pivotally ... (24)F£vin a ^ (M) ^ a
attached oAehousmgAgateis attached to the bracke and ^ (2g) ^ flow rate of fluent
is movable between a closed position covering the material Qmu^ ^ ... (24) fa ^ted b me
outlet and an open position spaced from the material outlet CTM *ectioMl ^ ofVme (24} m$is secondariiy
A permanent magnet is also attached to the bracket and 25 ^ a flQw ... aMbad<M screw (30). A
positioned at one end of the core offset from its longitudinal y * ^ 32 ^ m £
axls„^encuTM;ntfl°w slough the coil me mag net is ^^^^^0^(24^
repelled away from the core, and when current flow is . . , _' . . .... „!' . . . ,.
stopped the magnet is attracted to the core. Displacement of . A .bra^? <40> 18 TfflTfl'fJ? * ^ ( \ ^ r . . _ iL . housing (20). One end of the bracket (40) carries a gate (44).
the magnet responsive to current flow moves the gate 3°' ~y,AJ7 . .K J. .. _^ ,
, „„,°t, *_ „ , „, „ . •,•„,. The gate (44) is movable as shown by the directional arrow
between the open and closed positions. ^ , Z . ... ^ ■ .
(FIG. 3) between a closed position covering the material An object of the present invention is the provision of an outlet (2g) ^ ^ ^ spaced from me oudet (28)
improved electromagnetic meter. ^ other end of me (40) forms a yoke naving ^
BRIEF DESCRIPTION OF THE DRAWINGS 35 (4*>;1116 in^' SmfaCe °f each 81111 (46) C3lrieS a P6"TM"
nent magnet (48).
These and other attributes of the invention will become An electrical coil (60) is attached to the housing (20) and more clear upon a thorough study of the following descrip- a ferromagnetic core (62) is disposed within the coil (60). tion of the best mode for carrying out the invention, par- When the switching mechanism (12) allows the flow of ticularly when reviewed in conjunction with the drawings, 40 electrical current through the wires (13) to the coil (60), a wherein: magnetic field is produced which magnetizes the core (62).
FIG. 1 is a partial side elevational view showing a As best shown in FIGS. 3 and 5, the permanent magnets (48) granular chemical hopper mounted on the subframe of a are positioned at the ends of the core (62) offset to one side planting unit where the electromagnetic meter of the present of the longitudinal axis of the core (62). invention is attached between the hopper outlet and the 45 As shown in FIG. 3, the gate (44) and the magnet (48) are ground directed material delivery tube; arranged at opposite ends of the bracket (40) with the
FIG. 2 is a top plan view of the hopper with a portion magnet (48) disposed above the core (62). This structure cutaway to show the position of the meter; provides for a positive, gravity closing of the gate (44) since
HG. 3 is a sectional view taken along line 3-3 of FIG. *e h^ier e"d °f ^J***?(40) is <*P°"ite ^ ga* (44)„
2 showing the meter in side elevation; 50 *15 *°bP ^«oodthat other geometac arrangements will
_ also be included within the scope of the invention.
FIG. 4 is a sectional view taken along line 4—4 of FIG. T ^ , . - , .,,
„ . . ... 6 j In operation when current flows through the coil (60), the
2 showing the meter in rear elevation; and _L ^ . . .. . . ,,
6 ' magnetic field induced in the core (62) is reversed. When the
FIG. 5 is a sectional view taken along line 5—5 of FIG. fiey reVerses, the permanent magnets (48) carried by the
3 showing the meter in bottom plan. 55 (46) xc repeUed causing the bracket (40) to pivot about
BEST MODE FOR CARRYING OUT THE <42)Ttn^* ^"^"7
Tj^vention material outlet (28) to the open position. When the desired
amount of material has discharged through the outlet (28), Referring now to the drawings, wherein like reference the switch (12) is positioned to stop the flow of current numerals designate identical or corresponding parts 60 through the coil (60). The permanent magnets (48) are then throughout the several views, FIG. 1 shows the electromag- attracted to the iron core (62) causing the gate (44) to move netic meter (10) of the present invention secured to the back to the closed position. Material passing through the sloping bottom wall of a granular chemical hopper (1). The material outlet (28) is deflected from a vertical drop by the hopper (1) and a material delivery tube (3) are supported on gate (44) which is inclined when in the open position. The the subframe (5) of a seed planting unit (not shown). 65 V-shaped trough (32) acts to redirect the material through Granular material such as insecticide or pesticide passes the central opening (34) for discharge into the material from the hopper (1), through the meter (10), and is delivered delivery tube (3).