METHODE ET APPAREIL POUR REMPLIR LES POTS DE CULTURE DE PLANTULES

METHOD AND APPARATUS FOR FILLING SEEDLING POTS

Abrégé anglais

ABSTRACT OF THE DISCLOSURE
The present invention provides a method for filling
growth medium into seedling pots with perforated side and bottom
walls, comprising the following consecutive steps: a) placing a
tray with the seedling pots in a perforated matrix forming the
lid of a closed box, b) dipping the box with the tray and the
pots into an aqueous suspension of growth medium, c) sucking air
and water from the box until the pots are filled with growth
medium, d) lifting the box out of the suspension, and e) separat-
ing the tray with the pots from the box.

Revendications

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method for filling growth medium into seedling
pots with perforated side and bottom walls, comprising the follow-
ing consecutive steps: a) placing a tray with the seedling pots
in a perforated matrix forming the lid of a closed box, b) dipping
the box with the tray and the pots into an aqueous suspension of
growth medium, c) sucking air and water from the box until the
pots are filled with growth medium, d) lifting the box out of the
suspension, and e) separating the tray with the pots from the
box.
2. A method as claimed in claim 1, wherein the poros-
ity of the growth medium in the pots is controlled by a selection
of the concentration of the suspension and the sucking time.
3. A method as claimed in claim 1, where the water
content of the growth medium in the pots is controlled by raising
the box until the tray is above the surface of the suspension,
and sucking out the surplus water.
4. A method as claimed in claim 1, wherein the surplus
of growth medium on the tray is brushed away.
5. An apparatus for filling growth medium into seed-
ling pots with perforated side and bottom walls in a tray com-
prising: a) a first conveyor for moving the trays into the appara-
tus, b) a perforated matrix fitting to the underside of the tray
and the pots, forming a lid of a closed box connected to suction
means, c) means for placing the tray in the matrix, d) a vat for
containing a suspension of growth medium, e) means for dipping
the box with the tray and the pots into the vat and lifting the
box out of the suspension, and f) a conveyor for transporting
the tray with the filled pots out of the apparatus.
6. An apparatus as claimed in claim 5 comprising lock-
ing means for locking the tray with the pots into the matrix on
the box.

7. An apparatus as claimed in claim 5 comprising a
rotating brush for removing surplus growth medium from the tray
when leaving the apparatus.

Description

TITLE OF I~VE~TION:
~TH~D ~I~D APPI~RATUS FOR FILLING SEEDLING POTS.
TECHNICAI. FIELD:
The present invention relates to a new and useful
method and apparatus for filling growth medium into seed-
ling pots with perforated side and bottom walls. The inven-
tion is intended particularly for growing seedlings of re-
forestation trees.
BACKGROUND ART:
Seedling pots or containers filled with growth medium
such as peat or mixtures of peat and fibers and/or earth
are used to germina-te seeds and grow seedlings until they
are large enough to be transplanted into the soil. The con-
tainers are often perforated in order to drain surplus water
and to aerate the growth medium. The use of perforated con-
tainers makes possible the so called elevated growing, in
which water and nourishment are sprinkled onto tne upper
surface of the containers which are supported in apertures
of a plate or form depressions in this,whereas the walls and
bottoms of the containers are situated in an airfilled space,
which by so called air pruning will diminish the egress of
roots through the perforations.
The seedlings may be transplanted either together with
the perforated pot, which then must permit the passa~e of
roots through the perforations and be easily ruptured by
the roots, or the seedlings together with a lump of growth
medium may be removed from the pot and transplanted as such
into the soil.
The usual way to fill seedling containers is to fill
dry growth medium ln the containers, compact the medium and
water it to an appropriate moisture.
In order to get a suitable pore space the dry growth
medium must have a suitable structure and composition. E.g.
when growing forest plants, usually peat or mixtures of peat
and fibrous material.are used. In order to get a correct air
. . _ , . . .

capacity the pe~t must be compressed so that it expands
on wetting. For this purpose a special quality called
- chips-peat is produced. It consists of compressed granules
of peat and is supposed to swell to the correct volu~e when
watered.
DISCLOSURE OF INVENTION:
_ _ . .
According to the invention a tray with perforated pots
either formed as depression in one piece with the tray or
releasable hanging from apertures in the tray, is placed and
locked into a perforated matrix fitting to the underside of
the tray with the pots. The matrix forms the lid of a closed
box, which together with the matrix and the tray are dipped
into a suspension of growth rnedium in water. Water and air
are sucked out from ~he box. When the pots are filled with
growth medium the box is rised from the suspension. Water is
sucked from the box until the appropriate water content is
attained. Then the tray is removed from the box and a new
tray is placed in the box. Any surplus of growth medium on
the tray may be brushed away.
The porosity and the water content of the growth medium
in the pots may be deliberately controlled by the concentra-
tion of the suspension and by the time and force of the
sucking. It is possible in this way to compensate for diffe-
rent properties of the growth medium. ! '
The invention also comprises an apparatus for filling
seedling pots with growth medium according to the method
described above. The apparatus is defined in the following
description of the drawing.
i
BRIEF DESCRIPTION OF DRAWINGS AND BEST MODE FOR CARRYING
30 OUT THE INVENTION: -
.
Fig. 1 is a sectional length view of an apparatus
according to the invention. Fig. 2 is a sectional end view
of the same apparatus looking in the direction of the
arrows of line A-A in fig. 1. The figures also show the
function of the apparatus as will be described below.
A tray 1 with pots 2 perforated by slits 3 in the
walls and holes 4 in the bottoms is moved on a first con-
veyor 5 preferably comprising ropes 7 supporting the edges

or brims of the tray 1 and driven by wheels 7 or,to two
series of rollers 8 also suppor-ting the brims of the
- - _ tray 1. A box 9 hanging in a yoke or lifting beam 10 and
- with a lid 11 formed as a matrix fitting the underside of
the tray is raised by a hydraulic lift 12 on a bridge 13
against the underside of the tray 1 and the pots 2. The
perforations of the matrix must be small enough to prevent
the yrowth medium from passing. The matrix may be made of
netting or perforated plate. In the upper rim of the box
there are notches for the~rollers 8. The tray is clasped
by bars 14 lowered by hydraulics 15 in the yoke 10, which
lock the tray to the box as shown in Fig. 2. The rollers 8
are withdrawn by hydraulics 16 and both tray and box are
dipped into a vat 17 filled with a suspension 18 of growth
medium e.g. peat in water. This situation is shown in Fig. 2.
The suspension is held in movement by a mixing propeller 19
driven by a motor 20. Air and water are withdrawn from the
box 9 through a flexible hose 21 by a pump 22. The water may
be returned to the vat. When the pots 2 are filled with a
suitable amount of growth medium the box 9 is raised until
the tray is above the surface of the suspension 12. ~y selec-
ting the concentration of the suspension and the time and
underpressure in the box a suitable porosi-ty of the growth
medium can be achieved. The pumping is continued until the
growth medium has the correct water content for germinating
of seeds. An air-content of 40-45 % by volume and a water-
content of 40-45 ~ by volume has been recommended for forest
seedlings. Then the box 9 is raised until the rolls 8 can be
moved in under the brim of the tray. The bars 14 are lifted
from the tray. The box 9 is lowered as shown in Fig. 1. By
a friction drive, not shown, the tray 1 is moved onto a
second conveyor 23. Surplus of growth medium is brushed away
by a rotating brush 24.
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