Note: Descriptions are shown in the official language in which they were submitted.
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The invention relates -to a device for measuring -the
take-up speed of the sprinkler -tube of a sprinkling machine whose
piston mo-tor, driven by the sprinkling water, in its turn sets
the -tube winch in rotation via pusher pawls. In such a sprinkling
machine the flexible -tube is slowly coiled on the -tube reel dur-
ing the sprinkling process, the sprinkler carriage mounted at the
tube end sprinkling a strip of field of predetermined width during
this take-up process. The sprinkling width of the strip is
de-termined by the characteris-tic-s of the employed sector sprink-
10 ler and by the water pressure available at the sprinkler nozzle;the maximum possible length of the sprinkling strip corresponds
to the tube length available on the implement increased by -the
throwing distance of the sprinkler.
In such implements the tube winch is driven either by
means of a water turbine, which is directly supplied with the
sprinkling wa-ter being used, or with the aid of a pis-ton motor
using a small branched-off partial flow of the available water
quantity as a drive means; this driving water does not return to
the main sprinkler but is spread ou-t separately by means of a
20 minisprinkler in the immediate vicinity of -the sprinkling imple-
ment.
In implements with a driving turbine it is possible
l~ithout difficulty, and is customary açcording to the s-tate of
the a.rt, to measure and -to visually display the take-up velocity
of the sprinkling tube with the ai.d of a suitable tachometer as
a direct function of the rotary speed of the tube winch. In im-
plements wi-th piston-motor dri.ve, however, a velocity indication
has been unknown up to now. The difficul-ty appears to reside in
the fact that the piston drive in mos-t instances does not work
30 into a rotating shaft but transmits the driving force directly
to the circumference of the tube winch by means of pusher pawls.
In contrast to the.turbine implement, thereEore, no rotating
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-transmission part is availahle from which -the tachome-ter drive
can be branched off; morever, the piston motion is no-t uniEorm
bu-t intermittent.
For the user of sprinkling machines, however, the read-
abili-ty of the take-up speed is of essential signif~icance since
sprinkling cycles last mostly through -the night (the duration of
a tube take-up amountsto about 6 to 12 hours) and the farmer must
precalculate the time a-t which he has to revisit the implement
after the end of the sprinkling process.
T~e conven-tional pis-ton-driven implemen-ts, accordingly,
have the disadvantage of affording no speed readou-t but are ad-
vantageous in that they can be operated with a reduced expenditure
of energy.
The invention enhances the attractiveness of pis-ton-
driven reel-type sprinkling machines and enables the direct read-
ing of the take-up speed of the sprinkling -tube also with this
type of implement.
According to the present invention the pis-ton of the
piston motor is in driving connec-tion with the shaft of a tacho-
20 meter.
In this way it is possible to convert the reciprocatingpiston motion into a rotary motion which the -tachometer directly
displays as velocity, e.g. in meters per hour.
In accordance with one embocliment oE the invention, a
driving cord wound a,round a drive roller for the tachometer
secured to the cylinder of the piston mo-tor, engages with one end
of the reciprocating piston of -the piston mo-tor and has its other
end fixedly anchored by way of a restoring spring. This is par-
ticularly simple and insures a dependable motion transmission
30 from the piston to the tachome-ter shaft.
According to the invention it is also desirable that
speed values (m/h) are inscribed on the tachometer scale to the
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right and to the left oE a middle zero marking (piston position
at standstill). These values can -therefore be read direc-tly on
the scale of the tachome-ter~
In accordance with another embodiment oE the present
invention the scale of the tachometer comprise~ concentric cir-
cles for, e.g., four layers of the tube on the tube winch, along
with curvilinear scale markings extending downward in the direc-
tion of the tachometer center from the speed values inscribed on
the largest circle, their in-tersections with the concen-tric cir-
10 cles enabling the reading of the speed values corresponding tothe current position of the tube on the winch. Finally it is
also possible, in accordance with the invention, -to equip the
piston with a rack meshing with a pinion which is coupled di-
rectly or via a transmission with the tachometer. This solu-tion
of the stated problem also requires only simple means for imple-
menting the measuremen-t and indication of the speed.
The invention is illustra-ted in greater de-tail in the
drawing with reference to embodiments -thereof.
Fig. 1 shows in side view a piston drive for a tube
20 winch with the device according to the invention;
Fig. 2 shows a tachometer with scale markings; and
Fig. 3 shows another embodiment of the inven-tion sche-
matically and in side view.
~ ccordincJ to Fig. 1, there extends Erom the cylinder
1 the piston rod 2 whose reciprocating mo-tion is transmitted via
a kinematic system (not shown) to the tube winch of a sprinkling
machine and thereby causes the take-up of the tube in an inter-
mitten-t manner~ The piston rod 2 carries a mounting 3, fixedly
secured thereto, from which a driving cord 4 passes around a
30 roller 5, mounted on the cylinder 1, to a restoring spring 6
which is fixedly anchored at one end. When the piston rod 2
moves in one or the other direction according to the double-
headed arrow 7, the roller 5 is also entrained synchronously withthis motion in one or the other sense of rotation. The shaft 8
of roller 5 leads directly or indirectly to a tachometer whose
scale layou-t is represented in Fig. 2. At s-tandstill the pointer
9 is in its middle position. As soon as the piston rod 2 moves,
the pointer 9 is deflected to the riyht or -to the lef-t and remains
during the constant par-t of the piston stroke in a cons-tant de-
flection position, e.g. 10' or 10"; with each maximum deflection
the pointer 9 remains stationary for several seconds in its in-
10 dica-tlng position so as to afforcd sufficient readability for
the user.
The tachometer scale is furthermore so designed that
the reading associated with the current position can also be
carried out in dependence upon the current tube length ~the tube
is being wound on the drum in several layers). Moreover, the
scale layout takes into account the fact the the motion is inter-
mittent and indicates in its reading the mean value of the moving
phase and the intervening quiescent phase as required for deter-
mining the time.
According to Fig. 3 the invention can also be achieved
with a rack 11 which is fastened to the piston 2 and meshes wi-th
a pinion 12 which is connec-ted with -the tachometer (not shown)
either directly or by way oE a speed-chancJing transm:Lssion.