JPH0230787B2 - KAIHOGATAYOYUHOONRO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat retention furnace, particularly an open type heat retention furnace, for storing molten metal to be supplied to a die-casting machine or the like.

[Prior art]

As shown in FIG. 3, molten metal 12 is generally supplied to a die-casting machine 10 or the like by moving the molten metal in a heat-retaining furnace 14 maintained at a predetermined temperature through a suction pipe 18 and a discharge pipe under the operation of an electromagnetic pump 16. This is carried out by pressurizing and pumping through 20. As the furnace, an open-type molten metal insulating furnace is usually used, which has a simple structure, is inexpensive, and is easy to maintain.

By the way, in such a molten metal supply device, as the molten metal is supplied to the die casting machine, the level L of the molten metal 12 in the insulating furnace 14 decreases from La→Lb→Lc, and the suction head H of the molten metal 12 to the electromagnetic pump 16 decreases. It decreases from Ha→Hb→Hc,
The pumping capacity of the electromagnetic pump 16 is reduced. On the other hand, when the molten metal 12 is replenished from the supply path 22 and the level L of the molten metal rises, the suction head H for the electromagnetic pump 16 increases, and the pumping capacity of the electromagnetic pump 16 increases.

Therefore, in a molten metal supply device using an open type molten metal insulating furnace, the driving device 24 of the electromagnetic pump 16
A detector 28 for detecting the hot water level L in the heat insulating furnace 14 is connected to the operating device 26 for operating the heating furnace 14, and the discharge amount of the electromagnetic pump 16 is quantitatively controlled in accordance with changes in the hot water level L. ing. This prevents the precision of the cast product and the work efficiency from deteriorating.

[Problem that the invention seeks to solve]

However, the above-mentioned quantitative control of the electromagnetic pump has a drawback that the excellent advantages of the open heat retention furnace are offset by its complicated mechanism.

That is, quantitative control of the electromagnetic pump 16 is performed by correcting the excitation voltage of the electromagnetic pump 16 or changing the operating time of the electromagnetic pump 16, but in these controls, fluctuations in the molten metal level are Requires continuous detection. Therefore, the hot water level detector 28 constituting the control mechanism needs to have a structure that can follow the hot water level L, or a structure that can detect fluctuations in the hot water level L in fine steps. The operating device 26 is
In order to process the various data detected by the hot water level detector 28, a control mechanism including a large number of timers or an arithmetic mechanism including a microcomputer is required, and the drive device 24 also has a large structure corresponding to these. It is what it is.

As described above, while the conventional open-type molten metal insulating furnace has excellent advantages, it also has the disadvantage that it requires a complicated mechanism for quantitative control of the electromagnetic pump.

Therefore, an object of the present invention is to keep the molten metal level in the insulating furnace constant at all times in order to quantitatively control the discharge amount of the electromagnetic pump in an open-type molten metal insulating furnace that supplies molten metal to a die-casting machine or the like via an electromagnetic pump. To provide an open type molten metal insulating furnace with a simple structure and constitution capable of always keeping the suction head of an electromagnetic pump constant.

Incidentally, in order to maintain a constant suction head of an electromagnetic pump, a so-called pressurized heat insulating furnace is known, which changes the pressure inside the heat insulating furnace according to changes in the molten metal level. The pressure furnace has a heavy furnace body structure, and the maintainability of the molten metal supply device including the furnace body and casting workability are poor.

[Means for solving problems]

In order to achieve the above object, the open type molten metal insulating furnace of the present invention is an open type molten metal insulating furnace that stores molten metal to be pumped to a casting device etc. via a pressure pump. The immersed body is arranged to be able to move up and down, and a level detector for detecting the level of the molten metal is installed, and a means for raising and lowering the immersed body is provided on the upper part of the furnace body, and the immersion body is moved up and down through a lifting operation device. It is characterized by being connected to a detector.

The interior of the molten metal heat retention furnace is divided into a molten metal storage chamber and a molten metal supply chamber by a partition wall having a communication port at the bottom, and an immersion body is provided in the molten metal storage chamber and a molten metal level detector is provided in the molten metal supply chamber. be able to.

[Effect]

According to the open type molten metal insulating furnace according to the present invention, when the molten metal level drops, for example, the level detector detects this level drop and operates the lifting means via the lifting operation device to lower the immersion body into the molten metal. descend. As a result, the molten metal level rises, and when the level returns to a predetermined level, the molten metal level detector detects this level rise, stops the operation of the lifting means, and stops the descent of the immersion body. That is, the molten metal level is always maintained at a predetermined level. On the other hand, when the molten metal level rises, an operation substantially opposite to that described above is performed, and the molten metal level is returned to and maintained at a predetermined level.

In addition, if a compartment is provided inside the molten metal heat retention furnace,
There is an advantage that the hot water level detection by the hot water level detector is stable, and the raising and lowering operation of the immersion body is performed stably.

〔Example〕

Next, embodiments of the open-type molten metal insulating furnace according to the present invention will be described in detail below with reference to the accompanying drawings. For convenience of explanation, the same reference numerals are given to the same components as the conventional structure shown in FIG.
A detailed explanation thereof will be omitted.

FIG. 1 shows an embodiment of an open type molten metal heat retention furnace according to the present invention, in which an open type molten metal heat retention furnace (hereinafter referred to as a furnace) 14 is a storage furnace that supplies molten metal 12 to a die casting machine 10. An electromagnetic pump 16 is disposed between the die-casting machine 10 and the die-casting machine 10 via a suction pipe 18 and a discharge pipe 20, and a supply passage 22 is provided on one side wall of the furnace 14 opposite to the suction pipe 18.
is installed.

Here, in the open type molten metal insulating furnace 14 according to the present invention, an immersion body 30 having an elevating means 32 above the molten metal surface L is provided in the molten metal 12 via a bracket 38 so as to be able to rise and fall freely. A hot water level detector 40 is provided on the surface L via a bracket 42, and these elevating means 32 and the hot water level detector 40 are connected via an elevating operation device 44. The elevating means 32 includes, for example, a support rod 34 having a processed rack, a pinion that engages with the rack, and an elevating mechanism 36 that includes a drive device that drives the pinion. Lifting operation device 44
In response to the signal from the hot water level detector 40 that detects contact with and separation from the hot water level L, the immersion body 30 is moved downward when the body is separated from the hot water level, and the immersion body 30 is raised when it is in contact with the hot water level L.
It is configured to drive the lifting means 32.
Further, the surface of the immersed body 30 is made of a melt-resistant metal material, and the immersion volume is set to be less than the limit amount of molten metal that can be pumped out of the heat-retaining furnace 14 .

In the embodiment, the opening/closing means 48 of the opening/closing valve 46 of the supply path 22 is connected to the lifting/lowering operation device 44, so that the opening/closing valve 46 is automatically activated when the lower end of the immersion body 30 reaches the lower limit position M'. The immersion body 30 is opened to replenish the molten metal, and is automatically closed when the lower end of the immersion body 30 reaches the upper limit position M, that is, the set level position L of the molten metal surface.

In such a configuration, when the molten metal 12 is supplied to the die-casting machine 10 by the electromagnetic pump 16, the molten metal level in the heat retention furnace 14 tends to fall from the set level L, but at this time, the molten metal level detector 40 detects this. is detected, and as described above, the immersion body 30 is lowered via the lifting operation device 44 and the lifting means 32,
The volume of molten metal in the furnace corresponding to the volume of the supplied molten metal is replaced, and the molten metal level is maintained at the reference setting level L. On the other hand, molten metal is replenished from the supply path 22,
When the hot water level in the furnace 14 is about to rise, the immersion body 30 is raised as described above, and the hot water level is maintained at the reference setting level L. Therefore, the suction head H of the molten metal 12 in the furnace relative to the electromagnetic pump 16 does not change, and the discharge amount of the electromagnetic pump 16 is always kept constant.

In this way, the open-type molten metal insulating furnace according to the present invention maintains the molten metal level in the insulating furnace at a constant level, thereby eliminating the need for a complicated control mechanism that regulates the discharge amount of the electromagnetic pump, which was conventionally required. It can be made unnecessary. Moreover, since the above-mentioned molten metal level control mechanism merely maintains the molten metal level at a constant level by raising and lowering the immersion body, its structure is simple and control accuracy is improved.

FIG. 2 shows another embodiment of the open-type molten metal insulating furnace according to the present invention. In this embodiment, the inside of the heat-retaining furnace in the previous embodiment is divided into two parts: a molten metal storage chamber and a molten metal supply chamber.

That is, the inside of the heat retention furnace 14 is divided into a molten metal storage chamber 54 and a molten metal supply chamber 56 by a partition wall 50 whose lower part is open and serves as a communication port 52, and an immersion body 30 is provided in the molten metal storage chamber 54. The supply channel 22 is connected to the molten metal supply chamber 56, and the molten metal level detector 4 is connected to the molten metal supply chamber 56.
0 is provided and a suction pipe 18 is connected.

With this configuration, the turbulence of the molten metal 12 in the storage chamber 54 caused by the elevation of the immersion body 30 or the replenishment of molten metal from the supply channel 22 is blocked by the partition wall 50, and the wave motion of the molten metal surface in the supply chamber 56 is prevented. Since the amount of water is reduced, the detection by the hot water level detector 40 is stable, and the hot water level control is performed stably.

〔Effect of the invention〕

As explained above, the open type molten metal insulating furnace according to the present invention supports the immersion body immersed inside the molten metal so that it can rise and fall freely inside the molten metal via the molten metal level detector. Since the molten metal surface is always maintained at the molten metal level reference level set when the detector comes into contact with and separates from the molten metal surface, the suction head of the molten metal relative to the electromagnetic pump that presses the molten metal is always maintained constant. Therefore, in the conventional open-type molten metal heat-insulating furnace in which the melt level fluctuates, there is no need for a quantitative control mechanism for the pump discharge amount, which requires a complicated mechanism. Further, the mechanism for maintaining a constant level of the hot water level according to the present invention not only has a simple mechanism and is inexpensive, but also has high control accuracy, so that the quality of cast products and work efficiency can be improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of an open type molten metal insulating furnace according to the present invention, FIG. 2 is a sectional view of another embodiment, and FIG. 3 is a sectional view of a conventional open type molten metal insulating furnace. . 10... Die casting machine, 12... Molten metal, 1
4... Open type molten metal heat retention furnace, 16... Electromagnetic pump,
18... Suction pipe, 20... Discharge pipe, 22... Supply path, 30... Immersion body, 32... Lifting means, 34...
...Support rod, 36... Lifting mechanism, 38... Bracket, 40... Hot water level detector, 42... Bracket,
44...Lifting operation device, 46...Opening/closing valve, 48...
Opening/closing means, 50...Division wall, 52...Communication port, 5
4... Molten metal storage chamber, 56... Molten metal supply chamber.

Claims (1)

[Scope of Claims] 1. In an open-type molten metal insulating furnace that stores molten metal to be pumped to a casting device or the like via a pressure pump, an immersion body immersed in the molten metal is disposed inside the furnace body so as to be movable up and down, Further, a molten metal level detector for detecting the molten metal level is installed, and means for raising and lowering the immersion body is provided on the upper part of the furnace body, and this is connected to the molten metal level detector via a lifting operation device. Molten metal insulating furnace. 2. In the open-type molten metal heat retention furnace according to claim 1, the inside of the furnace is divided into a molten metal storage chamber and a molten metal supply chamber by a partition wall having a communication port at the bottom, and the molten metal is supplied to the molten metal storage chamber by an immersion body. An open type molten metal insulating furnace with a molten metal level detector installed in each chamber.