JPS642470B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a low-pressure casting device that can be easily mass-produced by separating a heat insulating furnace and combining a casting machine and a pressurizing device.

In the low-pressure casting method, in which molten metal is poured from below the mold, pressurized, and after the product solidifies, the pressure is reduced and the remaining metal at the sprue is discharged. Conventional low-pressure casting machines, in the case of pneumatic type, integrate the closed heat-insulating furnace and the casting machine. However, casting was not possible during replenishment, the closed heat insulating furnace was expensive, and since each casting machine had one heat insulating furnace, equipment costs were high, and operating costs were also high. Furthermore, since the apparatus itself is large, there are many restrictions on rationalization of the arrangement such as multiplication, and there is also the disadvantage that it is not suitable for producing a wide variety of products using the same casting machine. On the other hand, the electromagnetic type eliminates the need for a closed insulating furnace, but since it is integrated with a conventional insulating furnace, it has the same drawbacks as the pneumatic type in this respect, and there were also many restrictions on mass production.

The present invention eliminates the above-mentioned drawbacks, makes it possible to separate the insulating furnace and the casting machine, and uses a pressurizing device for low-pressure casting that allows easy control of pressurizing force, making work management easy and mass production possible. The present invention provides a low-pressure casting device that achieves the following.

That is, the low-pressure casting apparatus of the present invention uses an electromagnetic pump as pressurizing means, with one end serving as a connection port for communicating with the sprue of the casting machine, and the other end serving as a receiving port with a capacity of approximately one shot. The device is attached to a casting machine, and a large number of these casting machines with pressurizing devices are arranged in a movable or non-movable state on a stand or rail, and from one hot water heating furnace or melting furnace that is set in a movable state as necessary. The present invention is characterized in that molten metal is supplied to the inlets of each of the pressurizing devices so that a large number of casting machines can be supplied with the molten metal.

When supplying hot water, a large number of movable casting machines with pressurizing devices are moved one after another to a heat retention furnace or melting furnace (hereinafter typically referred to as a heat retention furnace) that is fixed at a certain location, or Move the insulating furnace installed in a movable state to a large number of casting machines with pressurizing devices arranged in an immovable state, and place the appropriate amount from the outlet of the insulating furnace to the inlet of the casting machine (the inlet of the pressurizing device). All you have to do is replenish the molten metal by regular means.

As shown in FIG. 1, an example of a pressurizing device attached to the above-mentioned casting machine is a connecting port 3 that communicates with a sprue pipe 6 provided in the mold cavity on one side.
A pressurizing device main body 1 having a boat-shaped cross section made of a heat insulating material and having a receiving port 2 for receiving molten metal on the other side, an electromagnetic pump 4 for electromagnetically transporting the molten metal in the main body 1 into a mold, and a sprue pipe. 6 and pressure sensing means for measuring the pressure in the space 3a formed by the connection port 3 and the molten metal surface and feeding it back to the electromagnetic pump 4 is particularly advantageous.

This pressurizing device will be explained in more detail with reference to the drawings. The electromagnetic pump 4 mounted on the pressurizing device main body 1 consists of a pump channel portion 4a directly in contact with the outer periphery of the device main body 1, and an inductor 4b surrounding the outside thereof. The volume of the pressurizing device main body 1 is set to such an extent that the lower end of the sprue pipe 6 is below the molten metal level when replenishing approximately one shot of molten metal.
The connecting port 3 has an inner diameter larger than the outer diameter of the sprue pipe 6, and there is sufficient space 3a between the connecting port 3 and the sprue pipe 6.
and a flange 3 at the open end of the connection port 3.
b is provided so that when the connecting port 3 comes into contact with the lower plate 5 of the mold, it makes good contact.

A pressure measurement hole 7 is provided in the side wall of the connection port 3 near the flange portion 3b, and a pressure transmission pipe 8 connects the hole 7 and a pressure measurement device 9. 10 is a controller that operates in response to a signal emitted from the pressure measuring device 9, and 11 is a pressure pattern generator, which is composed of a timer and a potentiometer. Reference numeral 12 denotes an output variable device for the electromagnetic pump 4, which is composed of a variable transformer, a thyristor, or the like, which changes the output of the electromagnetic pump 4 using the controller 10. 13 is a power source, 14 is a comparator, 15 is a set value, and 16 is a replenishment stop signal issued from the comparator 14, which is connected to a replenishment device (not shown).

The pressurizing device A for low-pressure casting is moved up and down by a cylinder 17 as shown in FIG. 2, and its connecting port 3 is brought into contact with a lower plate 5 provided at the lower end of a mold 18 during casting. After casting, the pressurizing device A is separated from the mold 18 and rotated and tilted about the shaft 19 to discharge the molten metal in the device body 1.

If the pressurizing device for low-pressure casting with the above configuration is used, the molten metal is pressurized by an electromagnetic pump, so the closed heat insulating furnace that was conventionally required for pressurizing becomes unnecessary.
Since the amount of molten metal in the shot can be pressurized, there is no need to attach a large heat-retaining furnace to the casting machine until the molten metal in the mold solidifies.

Therefore, as shown in FIG. 2, a large number of pressurizing devices A are attached under the mold 18 are prepared as one structural unit, one shot of molten metal is sequentially supplied to these, and the electromagnetic pump 4 is used. If the molten metal is pressurized and held until it solidifies, only one conventional large heat-retaining furnace is required, and it does not need to be sealed.

Therefore, in the apparatus of the present invention, a large number of the casting machines with pressurizing devices are disposed on a stand or a rail in a movable or non-movable state, and hot water is supplied to each of the pressurizing devices from one replenishment insulating furnace or melting furnace. It is characterized by being made to obtain.

Embodiments of the device of the present invention will be described below with reference to the drawings. Note that the casting machine used in these Examples is equipped with the pressurizing device A as explained in FIG. 2 above.

Example 1 In this example, casting machines 20, 20...
This is an example of an apparatus in which a large number of water heaters are arranged on a rotary table 21 and sequentially transported to a fixed hot water supply heat retention furnace 22 position. The rotary table 21 is the central power station 2
Casting machine 20 rotated by 3 and placed on it.
includes core placement, mold clamping, molten metal replenishment, casting pressure,
One casting cycle is completed through the holding, depressurizing, mold opening, and cleaning steps. When replenishing molten metal, when one casting machine 20 comes to the position of the fixed hot water supply heat insulating furnace 22, one shot of molten metal is replenished from the insulating furnace outlet 22a to the inlet 2 of the casting machine 20. (See Figure 4). The fully replenished casting machine 20 is transported by the rotary table 21, and at the same time, another casting machine 20 is transported.

The number of casting machines 20 provided on the rotating table 21 is preferably determined in relation to the rotational speed of the rotating table 21 so that casting is completed after one rotation.

Embodiment 2 In this embodiment, as shown in FIG.
20 are arranged in a fixed manner, and one shot of molten metal is supplied to the receiving port 2 of each casting machine 20 by the rotation of the insulating furnace 22. Molten metal supply is carried out in the same manner as in Example 1 (see FIG. 4).

Embodiment 3 In this example, as shown in FIG.
are arranged so as to be movable on rails 24 disposed along the lined casting machines 20, 20..., and the insulating furnace 22 is moved to the casting machine 20 that is ready for casting from the outlet 22a to 1. The present invention relates to an example of a device for replenishing molten metal for a shot. Heat retention furnace 22
After supplying the molten metal to one casting machine 20, it moves on the rail 24 and supplies the molten metal to the receiving port 2 of the other casting machine 20.

Embodiment 4 In this example, a large number of movable casting machines 20, 20, etc. with pressurizing devices are arranged on a loop-shaped rail 24, while a hot water heating furnace 22 is fixed at a casting position, and the casting machine 20 is mounted on a loop-shaped rail 24. This relates to an example of a device in which molten metal is replenished from the outlet 22a of the insulating furnace to the inlet 2 of the casting machine by moving the top of the molten metal 24 (FIG. 7). In the figure, 25 is a core conveyor, 26 is a product take-out device, 27 is a product delivery conveyor, and 28 is a spare machine replacement device for the casting machine. After the core is placed and the mold is closed, the casting machine 20 moves on the rails 24, and when it reaches a replenishment position, one shot of molten metal is replenished from the insulating furnace 22 to the casting machine inlet 2. After casting, casting machine 20
While moving on the loop-shaped rail 24, the mold is opened after solidification and depressurization, and the product is taken out of the mold by the product take-out device 26 by the conveyor 27 and carried out to the outside of the rail. On the other hand, after cleaning the inside of the mold, the core is placed, molten metal is replenished, and the casting cycle is repeated.

In each of the above embodiments, the hot water supply heat retention furnace may also serve as a melting furnace, or the heat retention device may be omitted. The method for replenishing molten metal from the insulating furnace to the inlet of the casting machine was not specifically described, but it goes without saying that it may be mechanical (for example, a tilting ladle) or electromagnetic method, and it is possible to use an empty method because the pressure is lower than the low-pressure casting pressure. A pressure type is also easy.

As is clear from the above description, in the device of the present invention, since the heat retention furnace (or melting furnace) and the casting machine are separated, only one heat retention furnace for hot water supply is required for many casting machines, and This eliminates the problems associated with conventional equipment, such as increased size and the use of closed furnaces in terms of equipment layout, space, costs, etc., as well as making it possible to perform each process in the casting cycle in separate locations, reducing the need for ancillary equipment and work. The number of employees can be reduced. Also,
It is possible to process molten metal in each casting machine, which stabilizes the quality of the product, and also makes the casting process easier, which reduces the labor of the operator and is very economical. Furthermore, even when tapping the hot water from the heat retention furnace using air pressure, the pressure is lower than that of conventional casting machines, and since an electromagnetic pump is used as the pressurizing means, the heat retention furnace can be an open type. be.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of a pressurizing device for low-pressure casting of the present invention, FIG. 2 is a side view of a casting machine equipped with the above-mentioned pressurizing device, and FIGS. 3 to 7 are respectively the low-pressure casting device of the present invention. It is a schematic diagram showing an example of. In the figure, 1... Pressurizing device main body, 2... Inlet, 3
... Connection port, 4 ... Electromagnetic pump, 6 ... Sprue pipe,
18... Mold, 20... Casting machine with pressure device, 22
...Insulating furnace for hot water supply, 24...represents a rail.

Claims (1)

[Claims] 1. Attach to the casting machine a pressurizing device using an electromagnetic pump as pressurizing means, with one end serving as a connection port for communicating with the sprue of the casting machine, and the other end serving as a receiving port with a capacity of approximately one shot. A large number of casting machines with pressurizing devices are arranged in a movable or non-movable state on a stand or rail, and the inlet of each of the pressurizing devices is placed from one hot water supply warming furnace or melting furnace installed in a movable state as necessary. A low-pressure casting device characterized by being able to supply molten metal to a large number of casting machines by replenishing it with molten metal.