[0001] This invention relates to an automatic cleaning device for a molding machine, embodying
a blow plate and/or blow nozzle.
[0002] In the molding operation where sand having a self-curing molding property is used,
such as self-curing molding sand or cold box sand, the remaining sand is cured if
it is left for a long period of time, so that the sand remaining within the blow head
and the blow nozzle after the molding operation must be immediately removed. In present
day operation the remaining sand heaped up on the blow plate which is dismantled from
the blow head is removed with a shovel, broom, air duster or the like for the cleaning
of the machine, but the sand remaining within the blow nozzle cannot be removed unless
an air duster is used. In the case of a number of blow nozzles this is troublesome
and takes a longer time to carry out a cleaning operation with a duster gun for every
blow nozzle, and results in a scattering of sand.
[0003] The inventor of this invention has made various studies and experiments to remove
the various disadvantages of conventional systems, and as a result has succeeded in
developing a blow plate and/or blow nozzle automatic cleaning device for use in molding
machines.
[0004] According to the invention there is provided an automatic cleaning device for a molding
machine comprising a blow plate, characterised by a turning frame for holding the
blow plate which frame is turned on a fulcrum provided at one end of a lifting frame
provided with a lifting cylinder, and a compressed air injection mechanism arranged
to clean the tilted blow plate.
[0005] By using the automatic cleaning device of the invention it is possible to collect
sand remaining on the blow plate into a lower-positioned sand box in a shorter period
of time without needing much labor, and by using a cleaning nozzle disposed opposite
each blow nozzle of the blow plate, it is possible to remove the remaining sand completely
in a single operation in which a plurality of nozzles are cleaned. This successfully
shortens time for cleaning of remaining sand and improves the working environment
and is labor saving.
[0006] One way of carrying out the invention is described in detail below, by way of example,
with reference to drawings which illustrate only one specific embodiment, and a modification
of that embodiment, and in which:-
Figures 1, 2 and 4 are elevations, partly in section, which show the sequence of operation
of an automatic cleaning device for removing sand on the blow plate of a molding machine,
Figure 3 is a side view of the cleaning device in the state shown in Figure 2,
Figure 5 is a front view which shows the cleaning of a blow nozzle,
Figure 6 is a detail sectional view of a cleaning nozzle, and
Figure 7 is a detail sectional view of a cleaning jacket.
[0007] Figures 1 to 6 describe in order one operational mode of an automatic cleaning device
of this invention. A molding machine comprises a blow plate 1 which is detachably
mounted on a blow head 24 in known manner. A turning frame 2 is provided, as shown
in the drawings, with a plurality of respective blow plate holding hooks 10 and cylinders
11 for operating the holding hooks. A lifting frame 3 is supported by a plurality
of lifting guide bars 6 inserted through a fixed frame 4, and by a lifting cylinder
9 provided in the frame 4, which lifting cylinder 9 raises and lowers the frame 3.
[0008] The turning frame 2 is pivotally mounted on a fulcrum 2a at one end of the frame,
in such a manner that it is tilted by more than an angle at which the sand on the
blow plate may fall. The fulcrum 2a is provided at the compressed air injection mechanism
side of the lifting frame 3 referred to below. The frame 2 is turned through an angle
of, for example 60° to 90°, and the turning operation is carried out by the actuation
of turning cylinders 5. In the device shown in the drawings by way of example, the
turning cylinders 5 are mounted on a plate 6a connecting the lifting bars 6, but the
turning cylinders 5 can be optionally positioned without being limited to this position.
[0009] Provision is made at the fulcrum 2a side for turning the turning frame 2 through
90°, which is necessary at intervals, and the compressed air injection mechanism disposed
opposite to the blow plate automatic sand-removing, cleaning device is constructed
as follows.
[0010] A vertical blow plate cleaning plate 12 is provided with a plurality of cleaning
nozzles 18 which at least correspond with the number of blow nozzles 16 arranged in
the blow plate 2, and a rubber end 15 is fitted on the end of each of the cleaning
nozzles 18. The blow plate cleaning plate 12 is fixed to one end of a cylinder rod
of a push-out cylinder 13 of the blow plate cleaning plate, which cylinder 13 is mounted
in a vertical portion 4a of the fixed frame. By actuation of the cylinder 13, guide
bars 14 slide to advance or retract the blow plate cleaning plate 12.
[0011] A sand discharging chute 7 is provided in the extension of the fixed frame, and is
arranged directly under the turning position of said turning frame 2, and leads to
a sand discharge box 8.
[0012] The automatic cleaning operation of the blow plate and/or blow nozzle will now be
explained.
[0013] When removing the remaining sand within the blow head 24, the lifting cylinder 9
is actuated to raise the lifting frame 3 and the turning frame 2 until the frame 2
comes to a close contact with the lower surface of the blow plate 1, in order that,
as shown in Figure 1, the blow plate attached to the blow head 24 of the molding machine
can be dismantled. Then the blow plate 1 is removed from the blow head 24 of the molding
machine on to the turning frame 2, and the blow plate holding hook cylinder 11 is
actuated so that the blow plate 1 is held at the turning frame 2 by the blow plate
holding hooks 10.
[0014] The lifting cylinder 9 is then operated, see Figure 3, to lower the blow plate 1
from the position of Figure 1 to its cleaning position shown in Figure 2. That is,
as shown in Figure 2, the remaining sand within the blow head 24 is taken out to the
cleaning position on the upper surface of the blow plate 1. When the turning cylinders
5 are operated the blow plate 1 held by the turning frame 2 is turned through 90°
as shown in Figure 4 so that all the remaining sand on the blow plate 1 falls for
collection down into the sand discharge box 8 provided beneath the sand discharging
chute 7.
[0015] When only the sand on the blow plate is removed, a 60° turn of the frame 2 will be
sufficient for the discharge of the sand.
[0016] The operation of removing remaining sand from the blow plate 1 may not remove sand
remaining in the blow nozzles 16 provided in the blow plate 1. In the present. device
the remaining sand in the blow nozzles 16 is completely removed by means of the compressed
air injection mechanism which is disposed opposite to the turned blow plate 1 and
is movable horizontally.
[0017] While gradually advancing the cleaning plate 12 by actuating the blow plate cleaning
plate,push-out cylinder 13 to the position shown in Figure 4, compressed air is injected
from the cleaning nozzles 18, which are fitted with the rubber ends 15. Even a small
amount of sand remaining adhered to the surface of the blow plate 1 is completely
removed by the injected air. If the cleaning plate 12 is further advanced and the
compressed air supply is continued for injection, the rubber ends 15 of the cleaning
nozzles 18 closely contact each blow nozzle 16 of the blow plate 1 as shown in Figure
5, and sand remaining within the blow nozzles 16 is quickly and completely discharged
into the sand discharge box 8 as shown in Figure 6. It is added that in the case of
a blow plate in which the position of the blow nozzles 16 is a little different from
the present device it is possible to conform the cleaning nozzles 18 to the blow nozzles
16 by somewhat displacing the cleaning nozzles by making the holes 23 for mounting
the cleaning nozzles as elongated holes H as shown in Figure 6.
[0018] Figure 7 is a fragmentary sectional view which shows another operational mode of
the invention, in which instead of the cleaning nozzles, a cleaning jacket 21 and
a flexible plate 20, such as rubber plate, are attached to the blow plate cleaning
plate 12. The cleaning jacket 21 communicates with an air intake pipe 17 and has an
air hole 22 at the same position as a hole in the rubber plate 20. The operational
method in this embodiment is the same, but with this system, there is no requirement
for positional adjustment of the air hole 22 even if the blow nozzles are differently
positioned and even when the blow plate has a different arrangement of a plurality
of blow nozzles 16 they can be cleaned in common.
[0019] Additionally, though not shown, it is possible to divide the circuit of the air supplied
to said cleaning nozzles 18 into a plurality of systems to remove in order the sand
remaining within the blow nozzle in each division. That is, when there are many blow
nozzles 16, a large amount of air is needed to clean all the nozzles simultaneously.
This means that the air pressure is considerably lowered and the injection power of
the air is weakened. The divided circuit makes possible efficient cleaning without
weakening the injection power by the air supplied in regular succession into respective
divisions.
[0020] The automatic cleaning device of the invention is capable of thoroughly removing
automatically and in a shorter period of time than hitherto, the sand remaining in
both the blow head and blow nozzles. The sand is not scattered, and therefore both
in terms of working environment and labor saving there are distinctive advantages
which cannot be obtained from conventional systems. Moreover, it is possible, by using
the cleaning device of the invention to replace a blow plate efficiently and in a
shorter period of time, which is necessitated by the replacement of a mold.
1. An automatic cleaning device for a molding machine comprising a blow plate (1),
characterised by a turning frame (2) for holding the blow plate (1) which frame (2)
is turned on fulcrum (2a) provided at one end of a lifting frame (3) provided with
a lifting cylinder (9), and a compressed air injection mechanism arranged to clean
the tilted blow plate.
2. A device as claimed in Claim 1, characterised in that the turning frame (2) can
be turned through 900 on the fulcrum (2a), and the compressed air injection mechanism is arranged opposite
to the fulcrum side of the frame (2) and is movable horizontally.
3. A device as claimed in Claim 2, characterised in that the compressed air injection
mechanism consists of a vertical blow plate cleaning plate (12) which carries two
or more cleaning nozzles (18) having rubber ends (15), and a cylinder (13) for moving
said cleaning plate (12).
4. A device as claimed in Claim 2, characterised in that the compressed air injection
mechanism consists of a cleaning jacket (21) which is provided with flexible plate
(20) having an air injection hole (22), and a cylinder for moving the cleaning jacket
(21).
5. A device as claimed in Claim 3, characterised in that the air supply to the cleaning
nozzles (18) is divided into a plurality of air supply circuits.