JPH049069Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention allows compressed air to flow through the molding sand filled in a casting flask to solidify the molding sand along the surface of the model plate. This invention relates to an improvement of a device for molding a mold by squeezing the entire body.

(Problems with Prior Art) Conventionally, in the production of the above-mentioned molds, it is common to use one molding machine to mold many types of molds with different model shapes. Therefore, the flow rate of compressed air supplied to the molding machine is generally set in accordance with the mold that is most difficult to mold. However, when a mold is made using a model plate with a simple shape model using a mold making machine with a compressed air supply flow rate set to suit the mold that is the most difficult to make, excessive molding sand may be produced. The compressed density is
There were problems such as impairing the air permeability of the mold, making the mold excessively hard, and causing various defective castings.

(Purpose) The present invention has been made to solve the above problems.

(Structure) Hereinafter, the structure of the present invention will be explained in detail based on the drawings of the embodiments. An upwardly facing cylinder 2 is installed in the center of the base 1, and an exhaust recess 3 and an exhaust hole 4 are provided at the upper end of the piston rod of the cylinder 2.
A table 5 having a
A model plate 7 with vent holes 6, 6 passing through it vertically is attached on top. Columns 8, 8 are erected at the four corners of the base 1, and in the middle position of the columns 8, 8 are 2 columns extending in the left-right direction.
Two flanged roller conveyors 9 and 10 are vertically installed at a required interval, and a flask 11 is movably mounted on the flanged roller conveyor 10 at the lower stage. Further, above the flanged roller conveyor 10, a filling frame 12 is supported so as to be able to rise via support means 13, 13 fixed to the columns 8, 8. A seal 14 is embedded in the lower surface of the filling frame 12. Moreover, a cover 15 that can be closed by forming a space at the upper end opening of the filling frame 12 is movably placed on the roller conveyor 9 with an upper flange. It is partitioned into upper and lower parts by 15a. A downward cylinder 16 is fixed at the center of the upper surface of the partition member 15a of the cover 15 with a piston rod passing through the partition member 15a airtightly, and a squeeze plate 17 is fixed to the lower end of the piston rod of the cylinder 16. has been done. Furthermore, the partition member 1 of the cover 15
5a, four air supply pipes 18, 18 extending higher than the upper end of the cover 15 are erected, and four air supply holes 19, 19 communicating with these pipes are formed. Further, an annular seal 20 is embedded in the lower end surface of the cover 15. In addition, the column 8,
A frame-like ceiling frame 21 is installed between the upper ends of 8, and a pressure tank 22 having a flat ceiling wall 22a and a flat bottom wall 22b is installed on the ceiling frame 21. Stomata 22c
It is communicatively connected to a compressor (not shown) via. Further, four exhaust holes 23, 23 are formed in the bottom wall 22b of the pressure tank 22 at positions directly above the air supply holes 18, 18, and the exhaust holes 23, 23 have an inverted conical shape on the lower surface. rectifier cone 24
It is designed to be opened and closed by four valves 25, 25 provided with. The valves 25, 25 are mounted on holders 26, 2 on the ceiling wall 22a of the pressure tank 22.
Lifting rods 27, 27 that are airtightly penetrated through 6
The upper ends of the lifting rods 27, 27 are connected by a connecting member 28. Further, an upward pneumatic cylinder 29 is fixedly installed on the pressure tank 22, and the connecting member 28 is fixed to the upper end of the piston rod of the pneumatic cylinder 29, and when the pneumatic cylinder 29 expands and contracts, the valve 2
5 and 25 are configured to move up and down to open and close the exhaust holes 23 and 23. 30 is the ceiling frame 21
The backing plates 31 and 32 fixed to the lower surface of the holder are seals. Further, a gate-shaped frame 33 is installed on the pressure tank 22, and a downward-facing hydraulic cylinder 34 is fixedly installed on the ceiling of the gate-shaped frame 33.
4a is designed to be able to stop after being extended an arbitrary distance. That is, the hydraulic cylinder 34
is connected to a hydraulic power source (not shown) via a 3-position, 4-way closed type switching valve 35.

(Function) Next, the function of the device configured as described above will be explained.

First, the table 5 and the model plate 7 are raised by the extension operation of the cylinder 2, and the flask 11 is placed on the model plate 7, and the filling flask 12 is placed on the flask 1 in a superposed state, and then, The extension operation of the cylinder 2 is temporarily stopped to stop the table 5 etc. from rising. Then,
The cover 15 is moved outward from the position directly above the filling frame 12, and a sand hopper (not shown) is brought into the position directly above the filling frame 12, and then the inside of the casting flask 11 and the filling frame 12 is filled with the sand hopper. Fill with foundry sand. Next, the sand container hopper is moved outside, and the cover 15 is again moved to a position directly above the filling frame 11. Subsequently, the cylinder 2 is further extended to raise the table 5, etc., and the filling frame 12 is raised.
The cover 15 is placed on top and the cover 15 is brought into contact with the backing plate 30, and at the same time, the air supply pipe 1
The upper ends of 8 and 18 are brought into contact with the lower surface of pressure tank 22 via seal 32, and air supply pipes 18 and 18 are connected to exhaust holes 23 and 23 in an airtight manner. By the way, if the shape of the model on the model plate 7 is complicated and filling with molding sand is difficult, the hydraulic cylinder 34 is contracted by switching the switching valve 35 to move the lower end of the piston rod 34a farthest away from the connecting member 28. and under this condition, the pneumatic cylinder 29
When the piston rod 34a is retracted, the connecting member 28 rises high and comes into contact with the lower end of the piston rod 34a. As a result, the exhaust holes 23, 23 are opened wide, and a large amount of compressed air is exhausted from the exhaust holes 23, 23 at once, passes through the air supply pipes 18, 18 and the air supply holes 19, 19 in order, and flows into the cover 15. , fill frame 12・
The flow passes through the molding sand of the casting flask 11, and the vent hole 6,
6 is discharged from the exhaust hole 4 through the recess 3. As a large amount of compressed air flows through the molding sand all at once, the particles of the molding sand flow through the vent hole 6,
6 and is deposited densely and firmly on the surface of the model plate 7. If the model plate 7 has a simple shape and is easy to fill with molding sand, the hydraulic cylinder 34 is extended by switching the switching valve 35 so that the lower end of the piston rod 34a is positioned closest to the connecting member 28. Keep it
When the pneumatic cylinder 29 is extended under this condition, the connecting member 28 rises slightly and comes into contact with the lower end of the piston rod 34a. As a result, exhaust hole 2
3 and 23 are opened small and a small amount of compressed air is discharged from the exhaust holes 23 and 23, and then is discharged from the exhaust hole 4 through the same route as in the previous example. When a small amount of compressed air flows through the foundry sand,
The foundry sand is deposited on the surface of the model plate 7 in a relaxed state compared to the previous example.

The piston rod 34a may be stopped at an intermediate position depending on the complexity of the model.

In this way, compressed air is caused to flow into the cover 15 in accordance with the complexity of the model on the model plate 7, and molding sand is deposited along the surface of the model plate 7. After the required time has elapsed, the pneumatic cylinder 29 is opened. The deflation operation closes the exhaust holes 23, 23, and the supply of compressed air to the cover 15 is stopped.

Next, the cylinder 16 is extended and squeezed by the squeeze plate 17 to remove the inside of the filling flask 12 and the flask 11.
Squeeze and solidify the foundry sand inside. After the squeeze is completed, the cylinder 16 is contracted to raise the squeeze plate 17, and then the cylinder 2 is contracted to lower the table 5. This results in
First, the cover 15 is attached to the collared roller conveyor 10.
The mold in the flask 11 is separated from the model plate 7 while being placed on the flanged roller. Thereafter, the flask 11 containing the mold is taken out, and another empty flask 11 is carried through the flanged roller conveyor 10 to a position directly above the model plate 7, thereby completing one cycle.

Note that the hydraulic cylinder 34 in the above embodiment
An appropriate lifting height adjustment mechanism for adjusting the lifting height of the valve 25 may be used, such as an electric cylinder. Further, the squeeze plate 17 in the embodiment may have a plate structure divided into a plurality of pieces (hereinafter referred to as squeeze mechanism) to obtain the same effect.

(Effects) As is clear from the above description, the present invention allows the valves 25, 25, which are provided to be movable up and down in order to open and close the exhaust holes 23, 23 of the pressure tank 22, to be adjusted to their rising height using a rising height adjustment mechanism. The valves 25 and 25 can be adjusted according to the complexity of the model on the model plate 7.
Since the opening degree of the exhaust holes 23, 23 can be adjusted by changing the rising height of the mold, the compressed air flow rate, which affects the degree of compression of the molding sand in the flask 12, can be appropriately selected to prevent the mold from solidifying excessively. This has excellent practical effects such as preventing the occurrence of defective castings.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view showing an embodiment of the present invention. 5... table, 6... vent hole, 7...
Model plate, 11... Casting flask, 15... Cover, 17...
...Squeeze plate, 18...Air supply pipe, 22...
Pressure tank, 22b...bottom wall, 23...exhaust hole,
25... Valve, 27... Lifting rod, 28... Connecting member, 29... Pneumatic cylinder, 34... Hydraulic cylinder, 35... 3-position, 4-way closed type switching valve.

Claims (1)

[Scope of utility model registration request] A casting flask 11 is removably installed at a position directly above a table 5 which has a model plate 7 with a vent hole 6 attached to its upper surface and is movable up and down. A cover 15 whose upper end opening of 11 can be closed by providing a space.
and a sand container hopper arranged so that it can be moved in and out and raised and lowered,
A squeeze mechanism 17 is provided in the cover 15 so as to be movable up and down, and a plurality of air supply pipes 18, 18 are provided upright in the cover 15 to communicate with the internal space of the cover 15, directly above the table 5 above the cover 15. A pressure tank 22 communicatively connected to the compressor is fixedly disposed at the bottom wall 2 of the pressure tank 22.
2b, a plurality of exhaust holes 23, 23 communicate with the air supply pipes 18, 18 when the cover 15 enters a position directly above the table 5 and is raised;
In the pressure tank 22, a plurality of valves 25, 25 for opening and closing the exhaust holes 23, 23 are fixed to the lower ends of the lifting rods 27, 27, respectively, and are movable up and down. , 27 on the ceiling wall 22a of the pressure tank 22, and the holder 26,
A connecting member 28 is installed on the upper ends of the lifting rods 27, 27, and an upward pneumatic cylinder 29 is installed on the lower surface of the connecting member 28. Fix the upper end of the piston rod of this downward pneumatic cylinder 29.
is attached to the upper surface of the ceiling wall 22a of the pressure tank 22, and directly above the connecting member 28 is connected to a hydraulic power source via a 3-position, 4-way, closed type switching valve 35 to control the expansion and contraction of the piston rod 34a. A rising height adjustment mechanism configured with a downward hydraulic cylinder 34 or an electric cylinder whose length is controlled, and in which the connecting member 28 comes into contact with the tip of the piston rod 34a to adjust the rising height of the valve 25. A mold making device characterized by being fixedly arranged.