JPS628260B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a low pressure casting apparatus.

(Prior Art) In a low-pressure casting device, two molds are alternately fitted into the stalk sprue of a casting furnace having a stalk sprue protruding from the upper surface, and while one mold is being poured, the other mold is being poured. Some perform a series of operations such as solidification process and product removal.

FIG. 6 shows the above-mentioned conventional device.

In this conventional device, a stalk sprue 101 is made to protrude greatly from the upper surface of the casting furnace 100, one mold A is fitted into this sprue part to perform casting, and when the casting is finished, the mold A is moved by a hanger 103.
is lifted up, the heights of the roller conveyors 104 and 105 are matched, the mold A is pulled out onto the roller conveyor 105, and a series of operations such as a solidification process and product removal are performed. Also, during this time, the mold B is transferred from the roller conveyor 106 to the roller conveyor 10.
4.Move it up and down to the stalk sprue part 1.
01 and perform casting.

By alternately using molds A and B in this way, low pressure casting can be performed efficiently.

(Problems to be Solved by the Invention) However, even with the above conventional device, there are the following problems.

In other words, as mentioned above, with the structure in which the stalk sprue greatly protrudes from the upper surface of the casting furnace, there is a problem that the molten metal inside the sprue cools down before the next cycle of casting is performed. Forced heating, etc. must be performed. Therefore, there are problems such as an increase in heating cost and, for example, changes in the composition of aluminum, making it impossible to obtain desired material properties.

Further, since the roller conveyor is separated into three parts, the heights of the three parts sometimes do not match, and there is a problem that the mold cannot be moved smoothly.

Therefore, the present invention was made to solve the above problems, and its purpose is to enable continuous casting without cooling the molten metal at the stoke sprue and to obtain a high-quality product. Our goal is to provide low-pressure casting equipment that can.

(Summary of the Invention) The present invention includes the following configuration to solve the above problems.

That is, two molds are alternately fitted into the stalk sprue of a low-pressure casting furnace that has a stalk sprue protruding from the top surface, and while one mold is being poured, the solidification process, product removal, etc. of the other mold is being performed. In a low-pressure casting apparatus that performs a series of operations, the lower part of the stalk sprue is moved to the side in the upper part of the low-pressure casting furnace so that only the mold fitting part, which is the part of the upper part of the stalk sprue that fits into the mold, is exposed upward. A plate is installed to enclose the low-pressure casting furnace and seal it.
The plate is disposed on the upper surface of the plate to surround the two molds, and is engaged with the lower mold side wall of the mold to fit the two molds into the stalk sprue, and the side of the stalk sprue. A rectangular frame body is provided which engages and guides the mold in a horizontally slidable manner between positions, a driving cylinder is provided which slides the mold along the rectangular frame body, and the rectangular frame body is brought into contact with the plate in the vertical direction. The present invention is characterized in that a rectangular frame body approaching and separating actuator is provided between the plate and the rectangular frame body in order to separate the mold and fit it into and remove it from the stalk sprue.

(Embodiments) Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In the figure, 10 is a low-pressure casting furnace having a fireproof wall structure, 12 is a crucible, and 14 is a stalk, which is connected to the furnace from a pressure pipe 16 via an appropriate pressure reducing valve.
Compressed air is sent into the crucible 12, and the pressure causes the molten metal in the crucible 12 to rise into the stalk 14, and is poured into the mold connected to the stalk sprue 18.

19 is a lower plate that seals the low pressure casting furnace 10. This lower plate 19 is the stalk sprue 1
The lower part of the stalk sprue 18 is surrounded from the side so that only the mold fitting part that fits into the mold on the upper part of the stalk 8 is exposed upward.

20 is a rectangular frame body, and the stalk sprue 18
The lower plate 19 is arranged in a corresponding position above.
It is moved up and down above the stalk sprue 18 by a contact/separation actuator provided between the stoke sprue 18 and the rectangular frame 20.

The contact/separation actuator is, for example, a link mechanism 22.
Consisting of:

That is, one end of the arm 28, 28' is pivotally supported at one end of each of the two rotating rods 24a, 24b which rotatably pass through the square frame 20, and a fixed shaft 26 fixed to the side wall of the lower plate 19. ,2
Arms 30, 30' are pivotably supported at one end of the arm 6', and the arms 28, 28' and the arm 3
The other ends of the hydraulic cylinder 32 and its rod 24 are connected in a floating state between the shafts X and X'.

A link mechanism 22 consisting of a similar pair of links and a hydraulic cylinder is provided on the other side of the square frame body 20.

When the hydraulic cylinder 32 is driven, the arms 28, 28' and the arms 30, 30' rise and fall, and the rectangular frame 20 approaches and separates from the lower plate 19.

Note that the contact/separation actuator of the rectangular frame body is not limited to the link mechanism described above, but may adopt any configuration such as using an appropriate cam mechanism or moving up and down using only a hydraulic cylinder.

Two molds 38 and 40 connected at a predetermined interval by a connecting plate 36 are inserted into the rectangular frame body 20, and are formed to be able to fit into the stalk oil port 18. The mold is configured to be slidable along the rectangular frame 20 by engaging a projection 42 provided on the lower mold into a groove 44 provided in the inner wall of the rectangular frame 20.

46a, 46b are cylinders, and the ends of the rods 48a, 48b and the lower molds 38a, 4 of the molds are
The protrusions 50a and 50b provided on the rod 0a are loosely connected to the pins 52a and 50b so that there is a gap between the rod end and the protrusions.
52b (see FIG. 5).
This interval absorbs the rise of the rectangular frame 20 caused by the contact/separation actuator, and also allows the rectangular frame 20 to rise by a predetermined amount to a position where the lower mold 40a is disengaged from the stalk sprue 18. Derod 48
a, 48b move back and forth, and the other lower mold 38a
The two connected molds are slid until they are positioned correspondingly above the stalk sprue 18.

FIG. 3 shows a partially cutaway perspective view of the rectangular frame 20. 21 is a notch through which the rod 48 of the cylinder 46 is inserted so as to be freely retractable.

Also, Fig. 4 shows the rectangular frame 20 and the lower plate 1.
9 is an explanatory diagram showing the positional relationship between the mold and the link mechanism.

Next, 54 is an upper plate, which is disposed corresponding to the upper sliding position of the two molds, and has two elevating rods 56a and 56b erected on its upper surface.
The end of a rod 64 of a cylinder 62 supported by a fixed support base 60 is connected to the communication portion 58 of the cylinder 60, and is moved up and down as the rod 64 moves forward and backward.

Two slits 6 are provided on the lower surface of the square frame body 20 and open downward along the sliding direction of the mold.
6a, 66b are provided, and the slits 66a, 6
A step portion 68 protruding inward is formed on the lower edge of 6b. Note that this step 68 is the stoke sprue 18
It is not formed at a position corresponding to the upper part, and a protruding rod flange portion, which will be described later, is configured to freely pass through the slit in the vertical direction.

Reference numeral 70 denotes a protruding rod protruding from the upper surface of the upper molds 38b and 40b, which has a flange portion 72 at its upper end, and is placed in the slit of the upper plate 54, with the lower surface of the flange portion 72 forming a stepped portion of the slit. The upper mold 38b is penetrated so as to come into contact with the upper surface of the mold 68, and when the upper plate 54 is raised, the upper mold 38b is pulled up and the mold can be divided.

A predetermined interval is formed between the upper end of the protruding rod 70 and the top wall of the slits 66a, 66b, so as to be able to absorb the rise of the mold that rises together with the rectangular frame 20 as described above.

A push pin 74 is pressed by a cylinder 76 to enter the upper mold 38b and push out the casting.

A pressure cylinder 78 presses a pin 80 protruding from the upper mold 40b to clamp the upper mold 40b and the lower mold 40a at the fitting position with the stalk oil port 18.

Reference numeral 82 denotes a pedestal, which is connected to a cylinder (not shown), and holds the upper mold 38b and the lower mold 38, which are separated by the rise of the upper plate 54 as described above.
It is designed to be able to freely move forward and backward between A and A.

The device of the present invention is configured as described above. Next, its operation will be explained.

First, one of the molds 40 is connected to the stoke sprue 18, compressed air controlled to a predetermined pressure is fed into the furnace 10 from the pressure pipe 16, and the pressurized casting process of the one mold 40 is performed. After a predetermined period of time has elapsed, a discharge valve (not shown) is opened to slightly lower the pressure inside the furnace 10 and lower the molten metal level in the stoke 14.

Next, the approaching and separating actuator of the rectangular frame body 20 is
As described above, the two molds are raised together with the rectangular frame 20, and one of the molds 40 is disconnected from the stalk sprue 18, and then the cylinders 46a and 46b are driven at this position to remove the connected molds. , so that the other mold 38 faces above the stalk sprue 18 , and the contact/separation actuator of the rectangular frame 20 is operated again to lower the rectangular frame 20 , and the other mold 38 is placed above the stalk sprue 18 . The pressurized pouring process is performed in the same manner as above.

On the other hand, during the pressurized pouring process of the other mold 38,
The one mold 40 detached from the stalk sprue 18
The solidification process and work processes such as mold cutting are performed.

In other words, one mold 4 has been moved to a position away from the stalk sprue 18 where the high-temperature molten metal is rising.
0 solidifies faster than conventional methods. After the solidification is completed, the cylinder 62 is driven to raise the upper plate 54. At this time, the flange portion 72 of the protruding rod 70 of one mold 40 engages with the slit stepped portion 68, and the protruding rod flange portion 72 of the other mold 38 engages with the slit stepped portion 68 during the pressurizing process. Since the upper plate 54 is raised, only the upper mold 40b of one of the molds 40 is raised together with the upper plate 54, and the molds are divided.

The solidified casting is attached to the upper mold 40b and rises. In this case, the lower mold 40a is engaged with the rectangular frame 20, so it will not rise.

Next, a cylinder (not shown) is driven to release the cradle 8.
2 is moved between the lower mold 40a and the raised upper mold 40b, and the cylinder 76 is driven to release the push pin 7.
4, the casting can be pushed out onto the pedestal 82, and the pedestal 82 can be moved back to take out the casting.
Next, necessary operations such as mold cleaning and application of a mold release agent are performed, and the upper plate 54 is lowered to fit the upper mold 40b and the lower mold 40a.

During this time, pressurized pouring of the other mold 38 has been completed, so the rectangular frame 20 is raised again, the mold slides, and the rectangular frame 20 is lowered to connect the one mold 40 to the stalk sprue 18 and start pouring. This method performs pressure pouring.

As described above, according to the present invention, since only the mold fitting part of the stalk sprue is exposed and the lower part of the sprue part is surrounded by a plate, the molten metal in the stalk sprue cools down between casting cycles. There is no need to provide a forced heating device as in the conventional method. Therefore, it is possible to reduce costs and at the same time provide high quality products with excellent material properties.

Furthermore, since the mold is slid within a single rectangular frame, it can be moved smoothly and can be fitted into and removed from the stalk sprue with high positioning accuracy.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. It is.

[Brief explanation of the drawing]

The figure shows a preferred embodiment of the device of the present invention.
The figure is a partially omitted side view, and FIG. 2 is a partially omitted front view. Fig. 3 is a partially cutaway perspective view of the rectangular frame, Fig. 4 is a schematic plan view showing the positional relationship of the rectangular frame, the lower plate, the mold, and the link mechanism, and Fig. 5 is the rod of the drive cylinder. It is an explanatory view showing a connection relationship with a mold. FIG. 6 shows a conventional low pressure casting device. 10...Low pressure casting furnace, 12...Crucible, 14...
... Stoke, 16 ... Pressure piping, 18 ... Stoke sprue, 20 ... Square frame, 22 ... Link mechanism, 24a, 24b ... Rotating rod, 26 ... Fixed shaft, 28, 30 ... Arm, 32 ... Hydraulic cylinder, 36 ... Connection plate, 38, 40 ... Mold, 42
...Protrusion, 44...Groove, 46a, 46b...Cylinder, 48a, 48b...Rod, 50a, 50
b...Protrusion, 52a, 52b...Pin, 54...
Upper plate, 56a, 56b... Lifting rod, 5
8... Connecting portion, 60... Fixed support base, 62... Cylinder, 64... Rod, 66a, 66b... Slit, 68... Step portion, 70... Projection rod, 72...
Flange portion, 74...Push pin, 76...Cylinder, 78...Press cylinder, 80...Pin, 82
... cradle.

Claims (1)

[Claims] 1. Two molds are alternately fitted into the stalk sprue of a low-pressure casting furnace in which the stalk sprue protrudes from the upper surface, and while one mold is being poured, the other mold is solidified. In a low-pressure casting apparatus that performs a series of operations such as product removal, the stalk sprue is installed in the upper part of the low-pressure casting furnace so that only the mold fitting part, which is the part of the stalk sprue that fits into the mold, is exposed upward. A plate is provided that surrounds the lower part from the side and seals the low-pressure casting furnace, and is arranged on the upper surface of the plate to surround the two molds, and is engaged with the lower mold side wall of the mold in a concave-convex manner. A rectangular frame body is provided that engages and guides the two molds in a horizontally slidable manner between a position where the two molds are fitted into the stalk sprue and a side position of the stalk sprue, and the mold is slid along the rectangular frame body. a drive cylinder is provided between the plate and the rectangular frame, and a drive cylinder for moving the rectangular frame toward and away from the plate is provided in order to move the rectangular frame toward and away from the plate in the vertical direction and to insert and remove the mold into the stalk sprue. A low pressure casting device characterized by: