JPS5823818B2 - Mold making equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold making device that creates a mold by compressing molding sand in a flask that has been matched to a model plate.

Conventionally, in order to sufficiently clamp the molding sand in the matched casting flask, it was necessary to increase the key pressure by increasing the diameter of the squeezing cylinder, or to install a cylinder protruding downward from the center of the jolt table. A conventional jolt mechanism supplies compressed air between a piston rod that is fixed to the piston rod and a cylinder in which the piston rod is slidably fitted, and moves the jolt table up and down by supplying and discharging the compressed air. However, in the former case, increasing the diameter of the squeezing cylinder made the machine larger and increased equipment costs, while in the latter case, the jolt mechanism itself was complicated and However, there were drawbacks such as loud noise.

The present invention has been completed with the aim of providing a mold making apparatus that can eliminate these drawbacks and sufficiently increase the hardness of the foundry sand in the flask.The embodiments shown in the drawings will now be described in detail.

Reference numeral 1 denotes a bed of a molding machine, and a vertical squeezing cylinder 3 is attached to the top surface of the bed 1, passing through the center thereof and having an upper flange portion 2 fixed thereto. , a pair of columns 4 are erected, and in the middle part of each column 4 is a pair of conveyors 6 made up of hollow rollers in which a plurality of rotatable flanged rollers 5 are pivotally supported at approximately equal pitches.
are laid out in a water drop shape with appropriate spacing in the middle.

Further, a rear lid 8 having a supply/discharge hole 7 for supplying and discharging fluid is fixed to the lower end surface of the squeezing cylinder 3, and a rear lid 8 is fitted to the upper end surface of the squeezing cylinder 3 so as to be slidable inside the squeezing cylinder 3. It has a through hole 11 through which the piston rod 10 of the squeeze piston 9 is slidably inserted, and a supply/discharge hole 12 on the side surface.
A front cover 13 is attached, and the piston rod 1
At the tip of 0, there is a table 1 with a model plate 14 attached to the top surface.
5 is fixed, and the table 16 to which the model plate 14 is attached is configured to be able to pass between the flanged rollers 5 of the pair of conveyors 6 described above, and is placed on the conveyor 6 to collect the molds being sent. It is possible to contact the frame 16.

Further, a compression plate 17 fixed to the upper plate of the column 4 is provided above the table 15 which can be raised and lowered,
The molding sand 18 charged into the flask 16 can be compressed between it and the model plate 14.

A sand hopper (not shown) that can move forward and backward is provided in the space between the lower part of the compression plate 17 and the upper surface of the flask 16 placed on the conveyor 6.

19 (ri) A main pipe connected at one end to the supply/discharge hole 7 of the skies cylinder 3 and at the other end to the A port of the 4-way 3-position switching valve 20. The P port is connected to a hydraulic power source 22 via a main pipe 19a with a check valve 21 connected to the middle, and a branch pipe 23 branched from the main pipe 19 has an impact generator 24 interposed in the middle. ℃
It is connected to a hydraulic power source 25 different from the hydraulic power source 22 .

26 is a casing of the impact generator 24 as shown in FIGS. 2 and 3, and on the circumference of the casing 26 there are supply holes 27 for supplying fluid, discharge holes 28 for discharging fluid, and Supply and discharge holes 29 connected to the branch pipe 23 are equally spaced, and a rotary 30 is provided inside, and a rotary shaft 31 protruding on both sides is supported by bearings 32 provided on both sides of the casing 26. A communication hole 33 is formed in the same plane as the surface of the casing 26 of the rotary 30 that includes the supply hole 27, the discharge hole 28, and the supply and discharge hole 29, and The supply hole 27, the supply/discharge hole 29, and the discharge hole 28 are configured to communicate with each other in sequence as they rotate, and the supply hole 27 and the hydraulic pressure source 25 are connected by a branch pipe 23a, and the discharge hole 28 is connected to the fluid It is connected to a pipe connected to a recovery tank 34, and is connected to the shock generator 2 via a branch pipe 23a from a hydraulic source 25.
The fluid that has reached the supply hole 27 of No. 4 is connected to the supply hole 27 and the supply/discharge hole 29 at both ends of the communication hole 33 of the rotary 30, which is rotating at a constant speed together with the rotating shaft 31 rotated by a variable speed motor (not shown). When they match, the communication hole 3
3, flows into the supply/discharge hole 29 and is sent to the branch pipe 23,
After the communication hole 33 is once shut off, both ends of the communication hole 33 are aligned with the supply/discharge hole 29 and the discharge hole 28, respectively, so that the fluid on the side of the supply/discharge hole 29 passes through the communication hole 33, passes through the discharge hole 28, and enters the tank 34. By continuously repeating this operation, the fluid on the side of the supply/discharge hole 29 is given a pulsating vibration, generating wave-shaped pulses as shown in FIG.

In addition, in order to make the hydraulic pressure source of the shock generator 24 the same as the hydraulic pressure source 22 that raises the squeeze piston 9, the main pipe 1 is
A bypass circuit may be provided in the middle of 9, and the impact generator 24 may be inserted in the middle of the bypass circuit.

Further, the supply/discharge hole 12 of the squeezing cylinder 3 has four openings 3.
It is connected to the B port of the position switching valve 20 via a supply/discharge pipe 35, and the T port of the 4-way 3-position switching valve 20 is connected to a tank 36 for recovering discharged fluid. The holes 7 and 12 are the main pipe 19 and the supply/discharge pipe 3, respectively.
5 are alternately connected to the hydraulic power source 22, and 37 is an electric motor that drives the hydraulic power source 22.25.

To explain an embodiment of mold making using an apparatus configured in this way, a model plate 1 attached to the top surface of a table 15 is used.
When the flask 16 is conveyed on the conveyor 6 to just above the table 15 while the upper end of the flanged roller 5 of the conveyor 6 is lowered below the upper surface of the flanged roller 5 of the conveyor 6, the 4-way, 3-position switching valve 20 is activated. Then, the A port and the P port and the B port and the T port are communicated, and hydraulic pressure is supplied from the oil pressure source 22 through the main piping 19 to the lower side of the squeezing cylinder 3 through the supply/discharge hole 7, and the table 15 is connected to the flange. After raising the attached roller 5 to a position above it and once stopping it, a sand hopper (not shown) is moved to the upper surface of the flask 16 to charge molding sand 18 into the flask 16, and then the sand hopper is moved to the upper surface of the flask 16. table 15
The table 15 is moved back to a rear position where it will not interfere even if the table 15 rises, and then the table 15 is raised again and the flask 1
When the impact generator 24 is operated while pressing the molding sand 18 in the molding flask 16, the hydraulic pressure intermittently applied through the branch pipe 23 and the main pipe 19 causes pulsations in the hydraulic pressure below the skies cylinder 3. The molding sand 18 inside vibrates slightly up and down,
Since compression molding is performed, the molding sand 18 is reliably filled into every corner of the model.

After completing such compression molding work, the shock generator 24 is stopped and the 4-way 3-position switching valve 20 is switched to connect the A port and the T port, and the B port and the P port, respectively.
Pressure oil from the hydraulic source 22 is supplied to the upper side of the squeezing cylinder 3 through the supply/discharge pipe 35 and the supply/discharge hole 12 to the squeeze piston 9.
When the table 15 is pushed down at the same time, only the molded flask 16 is left on the flanged roller 5 of the conveyor 6 with the receiver stopped halfway, and the table 15 with the model plate 14 attached is further lowered. The mold in the flask 16 and the model plate 14 are separated from each other, and the molded flask 16 left on the conveyor 6 is conveyed on the conveyor 6 to the side opposite to the empty frame conveyance side. After that, the molding process is completed, and thereafter, such a process is repeated to sequentially perform molding.

Furthermore, in the embodiment shown in FIG. 5, the impact generator and the piping relationship are different, that is, the main piping 51 is connected to the supply/discharge hole 7 provided in the rear wall 8 of the squeezing cylinder 3, Further, the main pipe 57 is connected to the A port of the shock generator 51 via a bypass pipe 50, and the P port on the opposite side is connected to a two-way, two-position switching valve 52 in the middle of the supply/discharge pipe 50a.
It is connected to a hydraulic power source 53.

The B port of the shock generator 51 is connected to a branch pipe branched from the supply/discharge pipe 54.58 connected to the supply/discharge hole 12 of the front cover 13, and the T port on the opposite side is connected to the supply/discharge port tube 54a
A 2-way, 2-position switching valve 55 is installed in the middle of the tank 56.
is connected to.

Further, the main pipe 5γ and the supply/discharge pipe 58 are the supply/discharge pipe so
a, 54a, and further connected to the main pipe 5
A four-way, four-position switching valve 59 is interposed between the supply and discharge pipes 7 and 58, and the supply and discharge holes 1 and 12 are alternately connected to a hydraulic power source 53.

The impact generator 51 is configured such that a rotary (not shown) rotatably inserted into a casing (not shown) rotates at high speed during operation (when pulsation occurs), and is supplied from a hydraulic power source 53 via the P port and the A port. In the exhaust hole 7, also the P port,
The amount of oil alternately supplied to the supply/discharge hole 12 via the A port is:
Since the structure is such that the amount of oil supplied from the P port and the A port to the supply/discharge hole 7 is larger than the amount of oil supplied from the P port and the B port to the supply/discharge hole 12, it is possible to The table 15 gradually rises while vibrating vertically.

In addition, when the table 15 for squeezing is only raised without pulsating vibration, the 4-way, 4-position switching valve 59 is switched to the state shown by the parallel symbol on the left, and the 2-way, 2-position switching valve 52, 55 is turned off. It is sufficient to supply hydraulic pressure from the hydraulic source 53 to the supply/discharge hole 7, and when lowering the table 15 for squeezing, the four-way, four-position switching valve 59 can be switched to the state marked with an x symbol. good.

Therefore, in the case of this embodiment, as in the previous embodiment, after casting the molding sand 18 into the matched molding flask 16, the squeezing cylinder 3 moves the molding sand 18 in the molding flask 16 onto the upper compression plate. 17 and activates the shock generator 51, the hydraulic pressure on the lower side of the squeezing cylinder 3 generates pulsating vibrations, giving pulsating vibrations to the model plate 14 via the piston/rod 10, etc., and causing the inside of the flask 16 to The molding sand 18 is pressed while being vibrated to form a mold.

After compression molding in this way, the 2-way, 2-position switching valves 52, 55 are switched to close the flow path, and the 4-way, 4-way
The position switching valve 59 is switched to the X symbol state, the squeegee table 15 is lowered, only the molded flask 16 remains on the conveyor 6, and the mold is cut out to complete the molding process.

In the above embodiment, it is of course possible to easily adjust the frequency, amplitude, etc. of the pulsating vibration by changing the rotational speed of the rotary in the casing or by changing the discharge amount of the hydraulic power source.

As is clear from the description of the above embodiments, the present invention makes it possible to mold a mold having sufficient hardness without particularly adjusting the diameter of the squeezing cylinder or adding the conventional jolt operation. Therefore, the mechanical device is miniaturized and the vibration generating mechanism has a simple structure, which has various advantages such as low noise.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a partially cutaway front view, FIG. 2 is a partially cutaway front view showing the internal mechanism of the impact generator, and FIG. 4 is a waveform diagram of pulses generated by the impact generator, and FIG. 5 is a partially cutaway front view showing the second embodiment. 3: Skies cylinder, 7: Supply and discharge hole, 10: Piston rod, 12: Supply and discharge hole, 14: Model board, 15: Table,
16: Casting flask, 17 Two compression plates, 18: Molding sand, 19: Main piping, 22: Hydraulic source, 23: Branch pipe, 24: Impact generator,
34: Tank, 35: Supply and exhaust pipe, 51: Impact generator, 53
: Hydraulic source, 56: Tank, 57: Main piping, 58: Supply/discharge pipe.

Claims (1)

[Claims] 1. A piston rod 10 with a table 15 fixed to its tip.
The supply and discharge holes 7° 12 of the squeezing cylinder 3 having the above are provided so as to be alternately connected to the hydraulic power source 22 via the main pipe 19 and the supply and discharge pipe 35, and further branch pipes 23 branched from the main pipe 19. A mold making device characterized in that one end of an impact generator 24 is connected to the engine, and the other end of the impact generator 24 is connected to a hydraulic power source and a tank. 2 Piston rod 10 with table 15 fixed to the tip
The supply/discharge holes 7° 12 of the squeezing cylinder 3 are provided so as to be alternately connected to the hydraulic power source 53 via a main pipe 57 and supply/discharge pipes 54, 58, respectively, and a bypass pipe 50 branched from the main pipe is provided. and a mold making apparatus characterized in that one end of an impact generator 51 is connected to a branch pipe branched from the supply/discharge pipes 54 and 58, and the other end of the impact generator 51 is connected to a hydraulic power source 53 and a tank 56. .