JP2006130537A - Tilting gravitation casting method and tilting gravitation casting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tilting gravity casting method and a tilting gravity casting apparatus which are adaptable to a cast product having every specification, can improve the quality and productivity of the cast product. <P>SOLUTION: A tilting tank 12 is installed so as to be in a vertical state by being turned by 90°from a horizontal position on a frame 10 through a tilting drive device 13 such as a hydraulic cylinder or a driving motor. An opening/closing door 15 for taking in/out a hopper 14d such as a vesse, in which l a molten metal W (molten aluminum metal) is stored, to be openable/closable at the one side in the longitudinal direction of the tilting tank 12. A molten metal detecting sensor 17 such as a temperature detecting sensor or an electric detecting sensor is installed in the state shown in Figure 2 at a boundary part X-X between a product part 16A and a feeder head part 16B of the upper and the lower molds 14a, 14b, that is, at the boundary part of the upper mold 14a. The molten metal detecting sensor 17 is connected to a controller 18 for controlling the tilting drive device 13 of the tilting tank 12 installed at the outer part of the tilting tank 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tilting gravity casting method and tilting gravity casting apparatus for casting a tire mold and the like using a tilting tank, and more specifically, can correspond to various patterns and sizes of cast products. It is related with the tilting-type gravity casting method which can aim at the improvement of productivity, and the improvement of productivity, and its tilting-type gravity casting apparatus.

  In general, in casting a tire vulcanization mold, it is necessary to fill a gypsum mold with a high density of molten aluminum metal in order to faithfully reproduce a complicated tread pattern of a tire. In order to realize a high-density filling of a gypsum mold with molten metal, a tilting gravity casting method using a tilting tank has been conventionally performed (for example, see Patent Document 1).

  For example, as shown in FIGS. 4 (a) to 4 (d), this tilt type gravity casting method includes a gypsum mold 2 (lower mold) accommodated in a tilt type tank 1 in an atmospheric pressure state and a hopper 3 such as a container. When the molten aluminum metal W put into the container is poured, the inside of the tilting tank 1 is depressurized (about -50 to 0 kPa), thereby reducing the internal nest of the cast product.

  The molten aluminum metal W is poured into the gypsum mold 2 and the casting frame 4b held in the lower mold 4a accommodated in the tilted tank 1 in a decompressed state, and at the same time the tilted tank 1 is in a horizontal state. As shown in FIG. 4 (c), it is filled by inclining in order from about 35 ° to 90 °, and after filling the molten aluminum metal W, the tilting tank 1 is pressurized (see FIG. 4 (d)). About 0 to 700 KPa), the molten metal filling efficiency is improved.

  By the way, the tire vulcanization mold is generally made of an aluminum alloy casting, and the mold is composed of a runner part, a product part, and a feeder part. First, it begins to flow along the runner, and the product part and the hot water part are sequentially filled.

  Further, the casting of the tire vulcanizing mold has a large aluminum casting amount of 50 kg to 80 kg per sector of the mold, and the filling speed of the large amount of molten aluminum metal determines the casting quality.

  In order to manage the filling speed as described above, the tilting type gravity casting apparatus as described above is used, and when filling the product portion, low speed filling (low speed of the tilting tank is used to prevent air entrainment). In order to improve the feeder effect, it is necessary to perform high-speed filling (high-speed tilting of the tilting tank) when filling the feeder part. In addition, when switching from the product section to the feeder section, it is necessary to change the filling speed of the molten aluminum metal.Therefore, at present, the switching point is visually confirmed and the speed point of the tilting gravity casting device is set. ing.

  However, the switching point differs depending on the tire pattern and size because the thickness and shape of the casting are different.In each case, it is necessary to visually check the switching point to adjust the tilting speed of the gravity casting device. It took time and effort, and it was necessary to check and set tilting conditions each time.

In addition, some product specifications make it impossible to visually check the switching point. Therefore, there is a problem that the conventional method lacks reliability and it is difficult to improve quality and productivity.
JP-A-62-114761

  The present invention has been devised by paying attention to such conventional problems, and automatically controls the tilting speed of the tilt type gravity casting apparatus by automatically detecting the switching point of the filling rate of the molten metal by the molten metal detection sensor. Thus, a tilting gravity casting method and a tilting gravity casting apparatus capable of dealing with a cast product of any specification and improving the quality and productivity of the cast product are provided. It is for the purpose.

  In order to achieve the above-mentioned object, the tilting gravity casting method of the present invention is configured so that the molten metal is detected when a molten metal is detected by a molten metal detection sensor provided at the boundary between the product part and the feeder part of the upper and lower molds. The gist is to increase the tilting speed of the tilting tank so as to increase the filling speed of the feeder section relative to the filling speed of the product section.

  Here, the filling speed of the feeder part is controlled to be 1.1 to 2.3 times faster than the filling speed of the product part.

  Further, the tilt type gravity casting apparatus of the present invention has a molten metal detection sensor installed at the boundary between the product part and the hot metal part of the upper and lower molds, and the molten metal detection sensor is installed outside the tilt type tank. The gist of the present invention is that it is connected to a control device that controls the tilt drive device.

  Here, the molten metal detection sensor is a temperature detection sensor or an electrical detection sensor, and the control device includes a tilt control unit and a drive unit.

  With such a configuration, it is possible to cope with a cast product of any specification, and it is possible to improve the quality and productivity of the cast product.

Since the present invention is configured as described above, the following excellent effects can be obtained. (a) In the tilt type gravity casting apparatus, the molten metal detection sensor can automatically and surely perform the boundary switching point between the molten metal product part and the hot metal part without visual observation. (b) Since the tilt speed control of the tilt type gravity casting apparatus can be automated, setting of tilt conditions for each tire pattern and size can be omitted.
(c) Conventionally, it is possible to reliably detect the specification in which the switching point cannot be visually confirmed, and it is possible to guarantee the molten metal filling speed accuracy with any specification.
(d). Since any type of cast product can be handled, it is possible to improve the quality and productivity of the cast product.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Note that the same components as those in the conventional example are denoted by the same reference numerals and description thereof is omitted.

  FIG. 1 shows a schematic configuration diagram of a tilting gravity casting apparatus for carrying out the tilting gravity casting method of the present invention. This tilting gravity casting apparatus has a tilting tank 12 with a hinge 11 on a gantry 10 as a fulcrum. Is placed so that it can tilt.

  The tilting tank 12 is installed so as to turn 90 ° from a horizontal position on the gantry 10 via a tilting drive device 13 such as a hydraulic cylinder or a driving motor so as to be in a vertical state. On the other hand, an open / close door 15 for opening and closing a hopper 14d such as a container containing the upper and lower molds 14a, 14b and the gypsum mold 14c and the molten metal W (aluminum molten metal) is attached to be opened and closed.

  As shown in FIG. 2, a temperature detection sensor or an electrical detection sensor is provided at the boundary portion XX between the product portion 16A and the feeder portion 16B of the upper and lower molds 14a and 14b, that is, at the boundary portion of the upper mold 14a. The molten metal detection sensor 17 is connected to a control device 18 that controls the tilt driving device 13 of the tilting tank 12 installed outside the tilting tank 12.

  In addition, in the same figure, 16C has shown the runner part, and the molten metal detection sensor 17 can also be provided in the lower casting_mold | template 14b of the boundary part XX of the product part 16A and the feeder part 16B.

  The control device 18 includes a tilt control unit 19 and a drive unit 20, and when the molten metal detection sensor 17 detects the molten metal W at the boundary portion XX between the product portion 16A and the feeder portion 16B, a detection signal is detected. Is output to the tilt control unit 19 of the control device 18, and a tilt speed signal is output from the tilt control unit 19 to the tilt drive device 13 of the tilt type tank 12 via the drive unit 20, so that the tilt speed of the tilt type tank 12 is increased. It controls to speed up.

  3 (a) to 3 (c) are process explanatory views in which the tilting gravity casting method of the present invention is implemented. As shown in FIG. 3 (a), the upper and lower molds 14a accommodated in the tilting tank 12 are shown. 14b and the gypsum mold 14c and the molten metal W placed in the hopper 14d such as a container, the tilted tank 12 which is in a horizontal state at the same time as the molten metal W is poured is shown in FIGS. 3 (b) and 3 (c). As shown, filling is performed by sequentially inclining at a predetermined speed from about 35 ° to 90 °, and the molten metal W is filled.

  At this time, the molten metal W starts to flow along the runner portion 16C and is sequentially filled into the product portion 16A and the feeder portion 16B, but the boundary portion X− between the product portion 16A and the feeder portion 16B. When the molten metal W is detected by the molten metal detection sensor 17 provided in X, the detection signal is output to the tilt control unit 19 of the control device 18, and the tilt tank 12 is tilted from the tilt control unit 19 via the drive unit 20. A tilting speed signal is output to the driving device 13, and the tilting speeds of the upper and lower molds 14a, 14b and the plaster mold 14c are increased, and the filling speed of the feeder 16B is controlled to be higher than the filling speed of the product part 16A. To do.

  In this embodiment, the filling speed of the molten metal W in the feeder part 16B is 1.1 to 2.3 times, preferably 1.5 to 1.8 times faster than the filling speed of the product part 16A. It was clarified from the results of the experiment that the control is good.

  That is, if it is less than 1.1, the hot-water supply effect cannot be improved, and if it exceeds 2.3 times, the filling speed is too high, which causes casting defects such as air entrainment.

  As described above, the switching point of the filling speed of the molten metal W is automatically detected by the molten metal detection sensor 17, and the tilting speed of the tilting gravity casting apparatus is controlled, so that any casting product of any specification can be handled. Therefore, it is possible to improve the quality and productivity of the cast product.

It is a schematic block diagram of the whole tilt type gravity casting apparatus for enforcing the tilt type gravity casting method of this invention. It is a plane explanatory view of the upper mold. (A)-(c) is process explanatory drawing in the case of implementing a tilting-type gravity casting method using a tilting-type gravity casting apparatus. (A)-(d) is process explanatory drawing in the case of implementing the conventional gravity casting method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tilt-type tank 2 Gypsum mold 3 Hopper 4 Casting frame W Aluminum molten metal 10 Mount 11 Hinge 12 Tilt-type tank 13 Tilt drive device 14a Upper mold 14b Lower mold 14c Gypsum mold 14d Hopper
DESCRIPTION OF SYMBOLS 15 Opening / closing door 16A Product part 16B Hot water supply part 16C Runway part 17 Molten metal detection sensor 18 Control apparatus 19 Tilt control unit 20 Drive unit

Claims (5)

When the molten metal is sequentially filled into the upper and lower molds by its own weight, the molten metal is placed in the runner, product section, and feeder section in the upper and lower molds while tilting the tilting tank containing the upper and lower molds at a predetermined speed. In the tilting gravity casting method in which casting is manufactured by sequentially filling,
When molten metal is detected by a molten metal detection sensor provided at the boundary between the product part and the hot metal part of the upper and lower molds, the tilting speed of the tilting tank is increased so that the hot water is filled with respect to the filling speed of the product part. A tilt type gravity casting method characterized by controlling the filling speed of the part to be faster. 2. The tilting gravity casting method according to claim 1, wherein a filling speed of the feeder part is controlled to be 1.1 to 2.3 times faster than a filling speed of the product part. In the tilting gravity casting apparatus configured to fill the molten metal with its own weight while tilting the tilting tank at a predetermined speed in the upper and lower molds installed in the tilting tank,
A molten metal detection sensor is installed at the boundary between the product part and the hot metal part of the upper and lower molds, and this molten metal detection sensor is connected to a control device that controls the tilt drive device of the tilt tank installed outside the tilt tank. Tilt-type gravity casting device characterized by that. The tilt type gravity casting apparatus according to claim 3, wherein the molten metal detection sensor is a temperature detection sensor or an electrical detection sensor. The tilt type gravity casting apparatus according to claim 3 or 4, wherein the control device comprises a tilt control unit and a drive unit.

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