JPH06208Y2 - Fixed surface furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a constant surface furnace used in a casting machine such as a die casting machine and a low pressure casting machine.

BACKGROUND ART Generally, in a casting apparatus such as a die casting machine, a molten metal such as molten aluminum in a constant temperature surface furnace is sent to a casting machine through a hot water supply pipe, and a cast product is formed in the casting machine. There is a constant surface furnace having a structure having a furnace main body and a crucible provided in the furnace main body and in which a molten metal such as molten aluminum is stored.

The seventh die-casting machine equipped with this type of constant surface furnace
As shown in the figure. In FIG. 7, a cast iron crucible 12 on a bottomed cylinder is arranged in a furnace body 11 in which a heater 10 is arranged, and a bottomed cylindrical dome 13 has an opening in the crucible 12. It is arranged downward. This dome 13 is made of cast iron or carbon,
In addition, a pressurizing chamber 13A is formed therein, and by supplying air to the pressurizing chamber 13A to push down the melt in the pressurizing chamber 13A, the melt in the crucible 12 can be kept at a predetermined level. There is.

One end of a hot water supply pipe 14 is connected to the upper part of the crucible 12, and a casting machine 15 is connected to the other end of the hot water supply pipe 14. The casting machine 15 includes an injection sleeve 16 connected to the other end of the hot water supply pipe 14, an injection plunger 17 arranged in the injection sleeve 16 so as to be movable back and forth, and an advance of the injection plunger 17 causes the injection sleeve 16 to move in the injection sleeve 16. And a mold 18 into which molten metal is press-fitted. An electromagnetic pump 19 is arranged in the hot water supply pipe 14, and the electromagnetic pump 19 supplies the molten metal in the crucible 12 to the hot water supply pipe 14.
Through the injection sleeve 16.

Here, the constant-bath furnace has a structure in which the flange portion 12A at the center of the crucible 12 is supported by the upper end surface 11A of the furnace body 11, but conventionally, the upper end surface 11A of the furnace body 11 extends horizontally. And the flange portion 12A of the crucible 12 has a horizontally extending ring shape.

[Problems to be solved by the device]

The crucible 12 is a heater 10 arranged in the furnace body 11.
It is heated by and is thermally expanded in the horizontal direction and the vertical direction. However, in the above-mentioned conventional example, the crucible 12
Since the flange portion 12A is formed in a horizontally extending ring shape, as shown in FIG. 8, the connection portion between the crucible 12 and the hot water supply pipe 14 also rises due to the upward expansion of the crucible 12. . That is, the furnace body 11 before thermal expansion
The distance from the upper end surface 11A to the axis of the hot water supply pipe 14 is h,
When the expansion coefficient is α and the temperature change is t, the displacement amount Δh of the shaft core end portion of the hot water supply pipe 14 due to thermal expansion is Δh = αth.

In this way, when the axial center end of the hot water supply pipe 14 is displaced upward, the hot water supply pipe 14 is inclined, and a gap S is created at the connection point between the crucible 12 and the hot water supply pipe 14, and the molten metal leaks from this gap S. The problem arises that

It is an object of the present invention to provide a constant surface furnace in which molten metal does not leak from a connecting portion between a crucible and a hot water supply pipe even when the crucible thermally expands.

[Means for Solving the Problems]

The constant temperature furnace of the present invention is connected to the furnace body and the other end of the hot water supply pipe having a flange portion supported on the upper end surface of the furnace body, the molten metal being stored therein, and one end communicating with the casting machine. A constant surface furnace having a crucible, wherein an upper surface of the furnace body is formed with a taper portion that is inclined downward toward the outside, and a flange portion of the crucible is formed with an inclined surface that is in contact with the taper portion. The extension line of this inclined surface and the extension line of the axial center of the hot water supply pipe intersect each other on the center line extending in the vertical direction of the crucible.

[Action]

In the present invention having such a configuration, due to the thermal expansion of the crucible,
Even if the crucible expands in the vertical direction and the connection between the crucible and the hot water supply pipe is apparently displaced upward, the crucible expands in the horizontal direction as well, so that the flange part extends along the tapered part via the inclined surface. Move outwards downwards.

At this time, since the thermal expansion coefficient of the crucible is the same in the vertical and horizontal directions, the intersection of the extension line of the inclined surface and the center line extending in the vertical direction of the crucible should always be located on the axial extension line of the hot water supply pipe. Therefore, the height of the axis of the hot water supply pipe becomes constant regardless of the thermal expansion of the crucible.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

In this embodiment, the structure for supporting the crucible to the furnace body is different from that of the conventional example, and the other structure is the same as that of the above-mentioned example. Here, in the present embodiment, the same components as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted.

In FIG. 1 and FIG. 2 showing a schematic structure of a die casting machine which is a casting apparatus, a ring member 2 is arranged on an upper end surface 1A of a bottomed cylindrical furnace body 1, and an upper end surface of the ring member 2 is disposed on the upper end surface 1A. Has a tapered portion 2A that is inclined downward toward the outside.

A cylindrical crucible 3 having a bottom is arranged inside the furnace body 1, and a flange portion 4 extending in a radial direction is provided at a central portion of the crucible 3, and a taper portion is provided on a lower surface of the flange portion 4. An inclined surface 4A that contacts 2A is formed. An extension line 1 of the inclined surface 4A and the tapered portion 2A
Are intersecting with the axis m of the hot water supply pipe 14 and the center line of the crucible 3 extending in the vertical direction, that is, the axis n of the crucible 3.

Crucible 3 for the inner peripheral surface of the upper end of the ring member 2 and the furnace body 1
A gap is formed between the outer peripheral surface of the crucible 3 and the outer peripheral surface thereof so that the crucible 3 does not interfere with the ring member 2 or the like when the crucible 3 expands in the horizontal direction. Further, a gap is formed between the bottom surface of the furnace body 1 and the crucible 3 so that the crucible 3 does not interfere with the bottom surface of the furnace body 1 when the crucible 3 expands in the vertical direction.

In this embodiment having such a configuration, due to the thermal expansion of the crucible 3 in the vertical direction, the connection portion between the crucible 3 and the hot water supply pipe 14 apparently displaces upward, but the crucible 3 also expands in the horizontal direction. Therefore, the flange portion 4 moves outward and downward along the tapered portion 2A of the ring member 2 via the inclined surface 4A, and the height of the axial center of the hot water supply pipe 14 does not change before and after the expansion of the crucible 3.

That is, as shown in FIG. 3, the dimension between the axis line n of the crucible 3 before expansion and the outer edge lower edge of the flange portion 4 is r, the axial center extension line m of the hot water supply pipe 14 and the outer edge lower edge of the flange portion 4 are Let h be the size of the crucible, α be the expansion coefficient, and t be the temperature change.
The lower edge of the outer end of the flange portion 4 is apparently caused by the thermal expansion of
The dimension Δh for upward displacement is Δh = αth ....

On the other hand, the dimension Δr at which the lower edge of the outer end of the flange portion 4 is displaced in the horizontal direction (left in FIG. 3) by the thermal expansion of the crucible 3 has the same coefficient of thermal expansion in the vertical direction and the horizontal direction. Δr = αtr.

Here, by displacing the outer edge lower edge of the flange portion 4 to the left in FIG. 3 by the dimension Δr, the outer edge lower edge and the taper portion 2 are displaced.
Although there is apparently a gap of dimension D with A, this dimension D is D = (hΔr) / r ... from (h / r) = (D / Δr).

Therefore, from the equation, D = (αtrh) / r = αth, and the dimension D is the dimension Δ.
Equal to h. Therefore, the intersection of the extension line 1 of the inclined surface 4A and the axis line n of the crucible 3 is always the axis extension line m of the hot water supply pipe 14.
As it is located above, the height of the hot water supply pipe 14 becomes constant regardless of the thermal expansion of the crucible 3.

According to the present embodiment as described above, the ring member 2 is arranged on the upper end surface 1A of the furnace body 1, and the upper surface of the ring member 2 is formed with the taper portion 2A that is inclined downward toward the outside, and the crucible 3 is formed. An inclined surface 4A that abuts the tapered portion 2A is formed on the flange portion 4 of the
Since the axial extension line m of the hot water supply pipe 14 intersects with the axial line n of the crucible 3, the hot water supply pipe 14 does not incline even when the crucible 3 thermally expands. Therefore, the crucible 3 and the hot water supply pipe 14 The molten metal does not leak from the connection part with.

Although the crucible has a cylindrical shape with a bottom and the flange portion 4 has a ring shape in the above-described embodiment, the crucible 5 has a box shape with a square bottom as shown in FIGS. The flange portion 6 provided on the outside of 5 may have a rectangular ring shape. In this case, the furnace body also has a box shape according to the shape of the crucible 5.

Further, the flange portion and the taper portion are not necessarily formed in a continuous annular shape, but may be divided into a plurality of pieces. In this case, it is necessary that the flange portion and the taper portion are arranged opposite to each other with the center line extending in the vertical direction of the crucible sandwiched therebetween.

Furthermore, in the above-described embodiment, the tapered portion 2A is formed on the ring member 2 provided separately in the furnace body 1, but the tapered portion may be formed integrally with the furnace body 1.

Further, in the above-mentioned embodiment, the casting apparatus is a die casting machine, but a low pressure casting apparatus in which the injection sleeve 16 and the injection plunger 17 are omitted and the casting machine 15 is composed of a mold may be used.

[Effect of device]

According to the present invention as described above, there is an effect that the hot water supply pipe does not incline even when the crucible thermally expands, and the molten metal does not leak from the connecting portion between the crucible and the hot water supply pipe.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a die casting machine as a casting device, FIG. 2 is a sectional view taken along the line II-II in FIG.
FIG. 4 is a sectional view showing the crucible before and after expansion, and FIGS.
FIG. 4 shows a crucible according to a modification of the present invention. FIG. 4 is a plan view, FIG. 5 is a sectional view taken along the line V-V in FIG. 4, and FIG. 6 is VI in FIG. -Cross-sectional view taken along line VI, No. 7
FIG. 8 and FIG. 8 show a conventional example, FIG. 7 is a view corresponding to FIG. 1, and FIG. 8 is a view corresponding to FIG. 1 ... Furnace body, 1A ... Upper end surface, 2A ... Tapered portion, 3, 5 ...
Crucibles 4, 6 ... Flange portion, 4A ... Inclined surface, 14 ... Hot water supply pipe, 15 ... Casting machine.

Claims (1)

[Scope of utility model registration request] 1. A furnace body, and a crucible having a flange portion supported on an upper end surface of the furnace body, a molten metal stored therein, and one end of which is connected to a casting machine and the other end of which is connected to the crucible. A constant surface furnace having, wherein a taper portion that is inclined downward toward the outside is formed on the upper end surface of the furnace body, and an inclined surface that is in contact with the taper portion is formed on the flange portion of the crucible, A constant surface furnace in which the extension line of the inclined surface and the axial center extension line of the hot water supply pipe intersect each other on the center line extending in the vertical direction of the crucible.