DETECTEUR DE PENETRATION POUR ROTOCULTEUR

DEPTH SENSING SYSTEM FOR TILLAGE IMPLEMENTS

Abrégé anglais

ABSTRACT OF THE DISCLOSURE
This invention is a depth control system for tillage implements com-
prising a ground contacting depth sensor that is rockably mounted
to the tillage implement, a rotary potentiometer mechanically connected
to the oscillating shaft of the rockably mounted depth sensor, an
electrical circuit having components to receive signals from the poten-
tiometer average out those signals and translate them into meter read-
ings in an instrument viewing panel at the operator's station. The
meter readings are given in inches and the meter dials can be adjusted
to suit the tillage implement upon which the depth control system is
mounted.

Revendications

The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A depth control system for tillage implements comprising a depth
sensing device that is maintained in ground contact over all surfaces
through an oscillatable mounting connection with a tillage implement,
a variable resistance wiper element that receives the movement of
oscillation through a rigid connecting means rheostat means
cooperating with the wiper element to form a variable resistance unit
that is mounted on the tillage implement and produces a series of
signals related to the degree of oscillation, electrical circuit
means to carry said signals to a meter box at a control station on
the prime mover for said tillage implement, milliameter means and
capacitor means in said meter box to receive said signals and to
average out said signals, and a meter dial providing direct depth
readings.
2. The apparatus of claim 1 wherein the depth sensing device has a
moving contact with the ground surface.
3. The apparatus of claim 2 wherein the variable resistance wiper
element is a rotary potentiometer.
4. The apparatus of claim 2 wherein the moving contact of the depth
sensing device is a rolling contact in the form of a swivel wheel
assembly, the mounting of said wheel assembly being in trailing
relationship to the tillage implement.
5. The apparatus of claim 2 wherein the moving contact of the depth
sensing device is a sliding contact in the form of a ski assembly,
the mounting of said ski assembly being in front of the tillage
implement or behind said implement.
6. The apparatus of claim 4 or 5 wherein height adjustment means are
provided for the ground contacting element of the depth sensing
device to enable control adjustments in the system that correlate
desired operating depth with meter readout depth upon initial assembly
of the system to various tillage implements.

7. The apparatus of claim 1, 2 or 3 wherein a plurality of depth control
systems are provided for a plurality of tillage implements in tandem,
and readout meters for all the systems are combined in a single
instrument panel at the operator's station and wherein a quick
disconnect coupler is provided for the leads from the plurality of
variable resistance units.
8. The apparatus of claim 1, 2 or 3 wherein a plurality of depth control
systems is mounted on each of a plurality of tillage implements.

Description

36J1~3
This invention relates to a depth control syst3m for tillage implements.
More particularly lt relates to a depth sensing and recording device for
a single till~ge implement, or ~or a plurality of tillage implements in
tandam. It provides accurate feedback informatio~ to the operator BS to
the true operating depth at all times.
This inYention is similar in function to that described and claimed in my
Ca~adian application No. 202,388. It differs, however, in the manner
in which changei in depth are sensed snd translated into readings
that may be obssrved at the operator's station.
The main comp~nents of the present invention comprise a depth se~sing
devioe in the form of a wheel assembl~ that is mounted in traili~g rela-
tionship t~ a tillage i~plement~ a rotary potentiomster mechanically con-
ne~ted to the wheel assembly~ an electrical circuit th~t recei~es the
signals induced by the rotary potentiometer, ave~ages ou-t the signals and
translates them into depth readings in the readout meters at the operator~s
station.
A ski assembly may be used as an alternative to a wheel assembly for certain
types of soil ~uGh as sand or sand-loam. The ski assembl~ is mounted in
front of the tillage i~plement so th~t it runs on a dry unworked surface.
It will function~ ho~ever, in a traillng position as well.
The wheel assembly is rockably mounted in a base plste that is secured to
the rear of the tillage implement. The mounting shaft of the wheel assembly
is integral therewith so that up and down movements of the wheel, as it
follows the ground ~ontour, are translated into oscillating movements of the
mounting shaft~ The shaft of the rotary potentiometer is rigidly oonnected
to this mounting shaft so that the oscillations are translated into signals
that provide ths depth readings.
A separate wheel assQmbly is attached to each implement o~ a tandem hookup.
This eD~bles the operstor to co~pare the depth reading~ of each implement
and adjust each implement to operate at the same depth or at preseleoted
.

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430[)3
variations in depth. The ski assembly can be used for certain soil types
whereas the wheel assembly can be used ~or all soil types.
The invention will now be more fully described in conjunction with the
accompanying drawings wherein:
Figure 1 shows a wheel assembly, mounting bases for different implements
and potentiometer parts in an exploded view.
Figure 2 shows a ski assembly with mounting means and the same potentio-
meter parts as Figure 1.
Figure 3 is a circuit diagram for the depth sensing and recording compon-
ents of the invention.
Figure 4 shows a three meter instrument panel with leads to three rotary
potentiometers.
;; As shown in Figure 1, wheel assembly 1 ;s rockably mounted in mounting
base 2 which is a mounting base adapted to a discer. A wheel height adjust-
ment nut is shown at 3. The shaft of rotary potentiometer ~ has a slide
fit reduced diameter end portion that is received in a smooth bore in
oscillating shaft 6 where it is secured by a set screw 6a. Shaft ~ is
welded to the wheel assembly mounting shaft so that it oscillates with it.
The potentiometer mount bracket is shown at 5. Shaft 6 is mounted in
bearing 7 in flange 8. An adjusting ring is shown at 9 and a pair of
clamps for the adjusting ring at 10. Cover 11 encloses the ent;re potentio-
meter assembly. The lead to the instrument panel is shown at 12. Mounting
base 13 permits assembly of the depth sens;ng unit to a tillage implement
other than a discer.
Figure 2 shows a sk; assembly with the same potentiometer components as
F;gure 1 so that these parts bear the same reference numerals. The rock-
able ski assembly is shown at 14, a compression spring to keep the ski
assembly ;n ground contact is shown at 15. A lower mount;ng plate 16
secures the ski assembly to the ~ront o~ a tillage implement.

~ L043~03
In Figure 3, a 12-volt battery 17 provides current to a 1 K potentiometer
19 which is mechanically connected to the wheel or ski, assembly. A 15 K
potentiometer 20 provides a second resistance in the circuit3 a 0-1 milli-
ammeter 21 receiYes the potentiometer signals and a 10,000 to 25~000
microfarad capacitor 22, bridging the milliammeter, averages out the
signals. SPST switches are shown at 18 & 23.
Figure 4 shows an instrument panel box and controls for three depth regu-
lators in tandem and three viewing meters for giving the depth readings in
inches. Instrument panel 24 has horizontally disposed meter dials 25 and
controls 26 that consist of a meter dial adjusting screw and a fast-slow
dial movement switch for each meter. The controls also include a light
switch, a power switch and a meter dial reversing switch. The reversing
switch reverses the direction of dial movement. This enables the operator
to use the meters interchangeably with either the wheel assembly or the
ski assemblyO Electrical lead 27 runs from the instrument panel 24 to a
quick disconnect coupler 28. Leads 29 in the coupler run to the rotary
potentiometers on the tillage implements. The F-S switch on the instrument
panel controls the responsiveness of the meter dial. In the S position the
meter dial responds slowly, giving an average indication of implement depth
as the wheel or ski assembly bounces along the soil. In the F position the
meter responds quickly. This is beneficial when the meter is used to indi-
cate cylinder posit;on or implement position when using a linear potentio-
meter.
It is pertinent to the present invention~o describe the method of assembly
of the depth control system to a tillage implement. After the wheel assembly
is installed on the implement, the operator places the implement down on
the working soil surface so that it is just touching the soil surface. Then
the operator turns the wheel height adjustment nut 3 (Figure 1) so that the
wheel is just touching the soil surface. Then both adjusting ring clamps
10 are loosened, the adjusting ring 9 rotated until the meter in the instru-
ment panel begins to move off of zero, at which point the adjusting ring
clamps are tightened up. The final step is to place the implement at the

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desired working depth in the soil, loosen the adjusting screw locking nut
on the instrument panel, turn the adjusting screw until the meter is at
the desired reading and tighten the locking nut. The depth control system
is now ready for use in the field and requires no readjustment on that
implement.
For greater accuracy, two or more wheel or ski assemblies can be mounted
on each implement and wired in series.
It is thus seen that the control system of the present invention provides
true depth readings at the operator's station, enabling the operator to
change the depth settings and have them confirmed in the meter readouts.