This invention relates to an apparatus for the
manufacture of moulded Sal leaf plates and a method thereof.
It is an age old practice of using dinner plates made of
disposable natural materials, viz. plant leaves. In religious
rituals and also in feasts, where a large number of people are
involved use of such disposable plates is a common practice.
Use of traditional dinner plates and tiffin bowls made of
stone, clay, ceramic, glass, plastic, metal etc. is costly and
also not hygenic as the same is not washed properly.
Such disposable plates are made from either fresh or
dehydrated leaves of large size, cut into size or stitched to
enlarge the area.
Banana leaves are popular almost all over the Indian
subcontinent. Lotus leaves are popular in the Southern
States. Sal leaves are popular in the Central and Eastern
States. For year round use of dehydrated leaves, partial
success has been made with banana and lotus leaves, because of
their fragility when dry. Sal leaves on the other hand, when
temper dried, acquire residual strength. It has a proven
commercial value and found access to rural and urban market
with equal popularity and choice. Unlike paper and plastic
plates, sal leaf plates even in dehydrated form can be rinsed
and disposed of after use by burning or dumping in a compost
pit, and is completely degradable and Eco-friendly.
sal (Shorea robusta) is a natural flora found widespread
in the forests of Central and Eastern India. The trees may be
tall upto 50 ft. Younger plants usually have an average leaf
foliage of 12 cm x 18 cm or smaller with increasing height of
the tree. The tree becomes barren during March and fresh
foliage comes during the next two months. Ten to twelve such
foliage may be hand stitched with wooden or grass picks to
form a circular disc like foil plate of average approximately
30 cm to 40 cm in diameter, which serves as a disposable
dinner plate. Conical shaped cups called Donas are also made
for serving yogurt or pudding like semisolid or fluid dishes.
This makes good cottage industry for villagers near forest
areas. In course of time these Sal leaf plates were improved
to have a leak proof flat base and raised edges by using
moulding type mechanical devices/ using pressure and heat.
There are disadvantages associate d with the present
apparatus and method of manufacture of the Sal leaf plates.
One of the main disadvantages with the present system is
that the machine or apparatus presently being used are
electrically heated to heat the mould or die. As such these
machines are used in towns where electricity is available.
Such towns are at considerable distance from the forest where
sal leaves are available. Thus transportation of the Sal
leaves to the town from the forest adds to the cost.
Another disadvantage with the present system is that the
machine or appartus used in the process is bulky and is not
portable. The operator has to stand to operate the machine.
Thus the fatigue of the operator is great resulting in low
productivity.
Yet another disadvantage with the present system is that
the heating coil for heating the mould or die lasts
approximately 7/8 days requiring frequent replacement of the
coils. This lowers the productivity and increases cost while
decreasing the benefits of the labour.
/ Therefore the main object of the present invention is to
propose an apparatus for trimming and moulding sal leaf plates
which are portable.
Another object to the present invention is to propose an
apparatus for trimming and moulding Sal leaf plates which is
completely manually operated.
Yet another object of the present invention is to
propose an apparatus for trimming and moulding Sal leaf plates
whereby heating is done by biomass firing and without using
any electricity.
A further object of the present invention is to propose
an apparatus for trimming and moulding Sal leaf plates in
which the operator can comfortably operate the apparatus
sitting on a stool with lesser fatigue and higher
productivity.
Still furthter object of the present invention is to
propose an apparatus for trimming and moulding Sal leaf plates
whereby the Sal Leaf collectors can stitch the plates and
mould these as finished products and market the same through
co-operative dealers directly to the urban consumers.
Yet a further object of the present invention is to
propose an apparatus for trimming and moulding Sal leaf plates
which can easily be used by people residing in remote villages
around forest areas, can operate and maintain the apparatus
independently with a little training and without heavy
investment for electrical connection and maintenance.
According to the present invention there is provided an
apparatus for the manufacture of moulded Sal Leaf Plates in
two operations of trimming and moulding comprising a trimming
machine and a moulding machine, the said trimming machine
consists of a blade or punch with a serrated edge fittled to a
holder, the said holder being attached to a vertical screwed
shaft for providing upward and downward movement of the
cutter blade by rotating the said screwed shaft with a wheel
attached to the ends of the said screwed shaft and the said cutter
blade or punch matching with a cutting blade guide or die fitted
on to the base plate for trimming the edges of the flat plates
and said moulding machine comprising: a heat exchanger/oven
placed in a suitable base frame , the said furnace is provided
with a flue gas outlet having a control valve for maintaining
desired temperature of the bottom die/lower moulding plate
in the range of 120° to 180°C, the said lower moulding plate
being fixed on the said furnace and a matching upper moulding
plate/top die is fitted to a support, the upper moulding plate
is moved up or down to place on the said lower moulding plateand
a pressure is applied to it with a lever with a trimmed sal
leaf placed betwen the said matching upper and lower moulding
plates.
The nature of the invention, its objective and further
advantages residing in the same will be apparent from the
following description made with reference to non-limiting
exemplary embodiments of the invention represented in the
accompanying drawings:
Figure 1 : Front view of the trimming machine
Figure 2 : Top view of the trimming machine
Figure 3 : Isometric view of the cutter blade with
holder arrangement and the screw
Figure 4 : Front view of the moulding machine
Figure 5 : Top view of the moulding machine
Figure 6 : Side view of the moulding machine
In accordance with the present invention the present
apparatus consists of two separate components or machines, one
for trimming the edges in a trimming machine to make the flat
stitched sal leaf plates circular or any desired size before
moulding and finishing in a moulding machine.
The trimming machine consists of a blade or punch (4) with
serrated cutting edge fitted to a holder (3) attached to a
vertical screwed shaft (8) for providing upward and downward
movement of the cutter blade (4) and apply pressure in it for
trimming the edges of the flat sal leaf plates when placed under
it. There is a matching bottom die or cutting blade guide (2)
mounted replaceably in the base plate (1) of the machine.
The cutter blade (4) is provided with a pressure plate
(10) which fits inside the cutter blade (4) with sliding
clearance. The pressure plate (10) is fixed to a spring support
(11) through a pair of pressure plate spring (9). The pressure
plate (10) will press firmly the sal lead plate before the cutter
blade (4) moves down and trims or cut the plate to shape with
the matching bottom die or cutting blade guide (2).
The cutter holder (3) along with the cutter blade (4) is
mounted on guide bush (5) with guide rod (6). At the top end
of the pair of guide rod (6) is a frame with screw holder (7)
through which the screwed shaft (8) is mounted. The screwed
shaft ( 8) is provided with a hand wheel (12) to manually rotate
to move the cutter blade and holder (4,3) to move up and down.
The moulding machine, consists of a heat exchanger or an
oven (14) placed in a suitable base frame (13). The heat
exchanger (14) is a double walled highly efficient oven in which
any type of biomass available in and around rural and forest
area can be used as firing fuel.
The oven (14) is provided with a proper exhaust system
flue gas outlet (16) along with a control valve for maintaining
desired temperature in the die (19,20).
A special type of multipurpose die (19,20) is fitted just
on the oven (14). The die (19.20) is composed of two matching
parts, the lower part or lower moulding plate (20) male part
is fixed on the oven to receive direct heat from the bottom
when fuel is burnt in the oven (14) and the upper part or upper
moulding plate (19),female part is fitted to a suitable frame
support (21). This part of the die (19) can move upward and
downward and place properly on the lower part of the die (20)
when a little pressure is given on it with the help of a lever
(22) provided with this. In both the upper and lower parts
there is a provision for changing male and female matching dies
(19,20) for moulding different sizes of plates and bowls.
The lower moulding plate (20) is fixed to a support (15)
which is circular and taper and provided with a flue gas outlet
(16) with a control valve.
The upper moulding plate or die (l9) is mounted on a support
(21). The support is slideably mounted onto a upper moulding
plate guide bush (18) to the upper moulding plate guide rod
(17).
The mechanism of lifting and lowering the upper moulding
plate or die (19) comprises of a upper moulding plate lifting
rod (23). The bottom end of the lifting rod (23) is fixed to
the base frame (13) and is provided with a pedal (24) arrangement
for lifting the upper moulding plate (19). At the top end of
the lifting rod (23) is provided with an additional handle
assembly (22). A tension spring (25), the lower end of which
is fixed to the base frame (13) and the top end is fixed to
one end of the handle (22) so that the upper moulding plate
(19) is always at top most position when not in use.
OPERATION AND PERFORMANCE
Two Sal leaf flat plates stitched together and properly
sized by the trimming machine are placed between the paired
pressure plates of the die (19,20), then pressure and heat are
applied for 12 to 15 seconds to form a moulded finished plate
of desired shape with raised edge and collar. The finished leaf
plates on cooling retain its shape for a longer period and the
smooth base becomes leak proof. Then these become marketable
after properly packed. In the similar way with the same machine
paper sheets can also be converted to moulded paper plates.
Several laboratory level and rural site test trials to wider
section of village communities including women have been
undertaken.
Since electrical connections are avoided, initial investment
for such installation is nil. Mobility and operation are
independent of higher technology or power failure or shortage
or supply of fossil fuels. Possibility of accident,hazard and
pollution are minimum. This machine can be kept in operation
continuously without any interruption in several shifts. With
proper planning the operation may be shared between families
almost round the clock.
This modified improved version of the Sal leaf plates
moulding machine will go a long way in improving the earning
livlihood of rural population residing in and around remote
places in the vicinity of wooded and forested areas. This will
also help generate additional self-employment and economic
upliftment to economically weaker section of the rural
populations.
Cutting of edge (trimming) of the flat leaves and moulding
for finished plates are having the following results in a study.
Time required for cutting edges: 3.5 minute for 100 flat
plates.
Time required for moulding each plate:12 to 15 seconds
depending on the fuel charging rate.
Body tempeature of the tie: l50°C to 160°C
Moulding of leaves starts after 7-8 minutes of fire charging
in the oven.
Quantity of biomass fuel required per hour: 1.2 kg to 1.4
kg.
Number of plates moulded (finished) per hour: 140 to 145.
The invention described hereinabove is in relation to a
non-limiting embodiment and as defined by the accompanying
claims.
We Claim:
1. A manually-operated, non-conventional energy driven, portable plate moulding
system for rapid production of sal leaf plates, the system comprising a moulding
device disposed at a distal end of the system configuration; and a pre-shaper
conveyably connected to the moulding device provided at a proximal end
receiving dehydrated leaves for reshaping the dehydrated leaves to a desired
profile through trimming operation, the trimmed leaves being conveyed to the
moulding device for moulding.
2. The system as claimed in claim 1, wherein the moulding device comprises a heat
exchanger (14) disposed on a metal frame (13) receiving heat generated through
firing biomass below the metal frame; and a replaceable die constituting of two
complementary parts (19, 20), the lower part (20) being detachably attached to a
top portion of the heat exchanger for receiving the upper part (19),the upper part
(9) being vertically movable along a lifting rod (21) for pressably seating over the
lower part (20) under a force exertable by a lever (22).
3. The system as claimed in claim 1, wherein the pre-shaper comprises a metal base
structure accommodating a both side opened bowl with vertical support members;
a replaceable cutter blade (4) releasably coupled to a holder (3) disposed on a top-
end of the bowl; a screwed shaft (8) providing pressable force and vertical
movement to the cutter blade rigidly fixed to the holder; a rotatable hand wheel
(12) arranging the vertical movement of the screwed shaft (8) being disposed at
the top end of the screwed shaft, a correspondingly configured cutting blade guide
(2) rigidly fixed to the base plate (1) of the pre-shaper.
4. The system as claimed in claim 2, wherein the heat exchanger (14) comprises a
multi-walled oven having a flue-gas outlet (16).
5. The system as claimed in claim 3, wherein the holder (3) with the cutter (4)
constitutes a pressure plate (10) slidingly fitted inside said holder (3) and jutting
slightly out of the cutter (4), said pressure plate (10) being mounted on to a
support (11) with a pressure plate spring (9).
6. The system as claimed in claim 5, wherein said cutter holder (3) along with said
cutter blade (4) is mounted on a guide bush (5) disposed on a guide rod (6).
7. The system as claimed in claim 6, wherein at the top end of the said guide rod (6)
a frame with screw holder (7) is provided for mounting the screwed shaft (8).
8. The system as claimed in claims 1 and 2, wherein the lower moulding plate (20) is
mounted on a plate support (15), said support (15) being circular and taper and
provided with a control valve.
9. The system as claimed in claim land 2, wherein the upper moulding plate (19) is
mounted on a support (21), said support (21) being slidably mounted on to an
upper moulding plate guide (18).
10. The system as claimed in claim 1, wherein said upper moulding plate or die (19)
is provided with a lifting and lowering means comprising an upper moulding plate
lifting rod (23), the bottom end of said lifting rod (23) being fixed to the base
frame (13) and is provided with a pedal (24), said lifting rod (23) being provided
with an additional handle assembly (22).
11. The system as claimed in claim 1 and 10, wherein said handle (22) is provided
with a tension spring (25) and fixed to the base frame (13) so that the upper
moulding plate (19) is always at top most position when not in use.
12. A manually-operated, non-conventional energy driven, portable plate moulding
system for rapid production of sal leaf plates, as substantially herein described
and illustrated with the accompanying figures.

The invention relates to an apparatus for manufacture of
moulded sal leaf plate in two operations of trimming and moulding
comprising a trimming machine and a moulding machine, the said
trimming machine consists of a blade or punch (4) with serrated
edge fitted to a holder (3), the said holder being attached
to a vertical screwed shaft (8) for providing upward and downward
movement of the cutter blade (4) by rotating the said screwed
shaft with a wheel (12) attached to the ends of the said screwed
shaft and the said cutter blade or punch matching with a cutting
blade guide (2) or die fitted on to the base plate (1) for
trimming the edges of the flat plates, and said moulding machine
comprising a heat exchanger/oven (14) placed in a switched base
frame (13) the said furnace is provided with a flue gas outlet
(16) having a control valve for maintaining desired temperature
of the bottom die/lower moulding plate (20) in the range of
120°C to 180°C, the said lower moulding plate being fixed on
the said furnace and a matching upper moulding plate(19)/top
die is fitted to a support (21), the upper moulding plate (19)
is moved up or down to place on the said lower moulding plate
(20) and a pressure is applied to it with a lever (22) with
a trimmed sal leaf placed betwen the said matching upper and
lower moulding plates.