JPH049070Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is based on the method of solidifying the molding sand along the surface of the model plate by passing compressed air through the molding sand filled in the molding flask. This invention relates to an improvement of an apparatus for molding a mold by squeezing the entire body.

(Prior Art and Problems) Conventionally, in the production of the above-mentioned molds, it is common to use one molding machine to mold other 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. but,
In this way, when a mold is made using a model plate with a simple shape model using a mold making machine whose compressed air supply flow rate is set according to the mold that is most difficult to make, excessive molding sand may be produced. There were problems such as compressed density, poor air permeability of the mold, excessive hardness of the mold, and 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 a table 5 having an exhaust recess 3 and an exhaust hole 4 is fixed to the upper end of the piston rod of the cylinder 2. A model plate 7 is attached with vent holes 6, 6 passing through the top and bottom. Columns 8, 8 are erected at the four corners of the base 1, and in the middle position of the columns 8, 8, there 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 placed 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 in the upper end opening of the filling frame 12 is movably placed on the upper roller conveyor 9 with a flange, and the cover 15 partitions the middle position of the square cylinder. It is partitioned into upper and lower sections by a member 15a. At the center of the upper surface of the partition member 15a of the cover 15 is a cylinder 1 facing downward.
A squeeze plate 17 is fixed to the lower end of the piston rod of the cylinder 16. Furthermore, the partition member 15 of the cover 15
In a, 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.

Further, a frame-shaped ceiling frame 21 is installed between the upper ends of the columns 8, 8, and the ceiling frame 21 is installed between the upper ends of the columns 8, 8.
1 is installed with a pressure tank 22 having a flat ceiling wall 22a and a flat bottom wall 22b, and the pressure tank 22 is connected to a compressor (not shown) through an air supply hole 22c. Moreover, the air supply pipes 18 and 1 at the bottom wall 22b of the pressure tank 22
Four exhaust holes 23, 23 are formed directly above the valve 8, and the exhaust holes 23, 23 are connected to four valves 2, each having an inverted cone-shaped rectifying cone 24 on the lower surface.
5, 25 to be opened and closed. The valves 25, 25 are fixed to the lower ends of lifting rods 27, 27 which are airtightly attached to the ceiling wall 22a of the pressure tank 22 via holders 26, 26, and the upper ends of the lifting rods 27, 27. Connecting member 2 is in between
8. In addition, the pressure tank 22
An upward facing pneumatic cylinder 29 is fixedly installed above, and the connecting member 28 is fixed to the upper end of the piston rod of the pneumatic cylinder 29, and the valves 25, 25 are moved up and down by the expansion and contraction of the pneumatic cylinder 29. It is configured to open and close the exhaust holes 23, 23 by opening and closing the exhaust holes 23, 23. 30 is a backing plate fixed to the lower surface of the ceiling frame 21, and 31 and 32 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, and the piston rod 34a of the hydraulic cylinder 34 is The length is such that it presses the upper surface of the lowered connecting member 28 when expanded, and separates from the raised connecting member 28 when contracted. Further, the contraction speed of the piston rod 34a of the hydraulic cylinder 34 is controlled by a meter-out circuit system. That is, the hydraulic cylinder 34 is communicatively connected to a hydraulic power source (not shown) via a directional switching valve 35, and a flow rate adjustment valve 36 is provided between the rear cover of the hydraulic cylinder 34 and the rear of the directional switching valve 3. It is being

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

First, by the extension operation of cylinder 2, table 5
Then, the model plate 7 is raised, and the casting flask 11 is placed on the model plate 7, and the filling frame 12 is placed on the casting flask 11 in a superposed state, and then, the extension operation of the cylinder 2 is temporarily stopped and the Stop the rise of 5th mag. Then,
The cover 15 is moved outward from the position directly above the filling frame 12, and the sand hopper (not shown) is moved to the outside of the filling frame 1.
Then, molding sand is introduced into the flask 11 and the filling frame 12 using the sand hopper. Next, the sand container hopper is moved outside and the cover 15 is moved again to a position directly above the filling frame 11. Subsequently, the cylinder 2 is further extended to raise the table 5, etc., and the cover is placed on the filling frame 12. 15 and the cover 15 is brought into contact with the cover 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 operating the directional control valve 35 to separate the lower end of the piston rod 34a from the connecting member 28. Under this condition, when the pneumatic cylinder 29 is extended, the connecting member 28 rises at high speed and the exhaust holes 23, 23 are quickly opened. , 23, passes sequentially through the air supply pipes 18, 18 and air supply holes 19, 19, flows into the cover 15, flows through the molding sand of the filling frame 12 and casting flask 11, and flows through the vent holes 6, 6. , and is discharged from the exhaust hole 4 through the recess 3. As such a large amount of compressed air flows through the molding sand at once, the particles of the molding sand are caused to flow toward the vent holes 6, 6, and are densely and firmly deposited on the surface of the model plate 7. In addition, if the shape of the model on the model plate 7 is simple and filling with molding sand is easy, the flow rate regulating valve 36 is adjusted so that the contraction speed of the piston rod 34a of the hydraulic cylinder 34 becomes an appropriate speed, and then Then, by operating the directional switching valve 35, the hydraulic cylinder 34 is extended to bring the lower end of the piston rod 34a into contact with the upper surface of the connecting member 28, and then the rear of the directional switching valve 3 is operated to extend the piston rod 34a of the hydraulic cylinder 34.
Make it possible to contract. When the pneumatic cylinder 29 is extended under this condition, the piston rod of the pneumatic cylinder 29 is extended under pressure control by the piston rod 34 of the hydraulic cylinder 34 which is meter-out controlled, and as a result, the connecting member 28,
The valves 25, 25, etc. rise at a relatively low speed, and the exhaust hole 2
3,23 will be gradually opened. As a result, the compressed air in the pressure tank 22 flows into the pressure tank 15 little by little compared to the previous example, causing the particles of foundry sand to flow toward the vent holes 6, 6, but the amount of compressed air is small and The molding sand is compressed to some extent by the inflow of air and is almost unable to move, so even if the valves 25, 25 are raised further and the exhaust holes 23, 23 are fully opened, and a large amount of compressed air flows in, the molding sand will not move. The packing density of the molding sand is not increased, and the molding sand is deposited on the surface of the model plate 7 in a relaxed state compared to the previous example.

In this way, compressed air is allowed 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 a required period of time has elapsed, the pneumatic cylinder 29 is contracted to close the exhaust holes 23, 23, and the supply of compressed air to the cover 15 is stopped. Next, the cylinder 16 is extended and the squeeze plate 17 squeezes and solidifies the molding sand in the filling frame 12 and the casting flask 11. 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. As a result, first, the cover 15 is placed on the flanged roller of the flanged roller conveyor 9, then the filling frame 12 is placed on the supporting means 13, 13, and finally the flask 11 is placed on the flanged roller of the flanged roller conveyor 10. The mold in the flask 11 is separated from the model plate 7 while being placed on the rollers. Thereafter, the flask 11 containing the mold is taken out, and another flask 11 is carried to a position directly above the model plate 7 via the flanged roller conveyor 10, thereby completing one cycle.

Note that the hydraulic cylinder 34 in the above embodiment
may be an appropriate rising speed adjustment mechanism that adjusts the rising speed of the electric cylinder valve 25. Also,
Even if the squeeze plate 17 in the embodiment has a plate structure divided into a plurality of pieces (hereinafter referred to as a squeeze mechanism), similar effects can be obtained.

(Effects) As is clear from the above explanation, the present invention allows the valves 23, 23, which are provided to be movable up and down to open and close the exhaust holes 23, 23 of the pressure tank 22, to be able to adjust their rising speed using a rising speed adjustment mechanism. Since I configured it as
Since the rising speed of the valves 23, 23 can be changed depending on the complexity of the model on the model plate 7, the flask 12
The compressed air flow rate, which affects the degree of compaction of the molding sand inside, can be appropriately selected to prevent the mold from being excessively solidified, and has excellent practical effects such as preventing the occurrence of defective castings. play.

[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 rod, 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.

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. Frame 11
A cover 15 is provided in which the upper end opening can be closed with a space, and a sand container hopper is disposed so as to be movable in and out and can be raised and lowered. A plurality of air supply pipes 18 , 18 communicating with the space are provided upright, and a pressure tank 22 , which is communicatively connected to the compressor, is fixedly disposed above the cover 15 and directly above the table 5 . bottom wall 2
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 upward pneumatic cylinder 29.
is attached to the upper surface of the ceiling wall 22a of the pressure tank 22, and directly above the connection member 28, a piston rod 34a is connected to a hydraulic power source via a flow rate adjustment valve 36 and a direction switching valve 35 to adjust the contraction speed. A rising speed adjustment mechanism is fixedly provided, which is composed of a downward hydraulic cylinder 34 or an electric cylinder that is controlled to adjust the rising speed of the valve 25, and the connecting member 28 comes into contact with the tip of the piston rod. Characteristic mold making equipment.