JP2012024807A - Manufacturing device for tire molding die, and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing device for a tire molding die which can prevent occurrence of an oxide film on a casting product and a blow hole inside the product and improve quality of a casting, and a manufacturing method therefor.SOLUTION: The tire molding die is composed of a casting frame 1 for molding a casting, and a container-shaped molten metal storage device 2 installed adjacent to a runner 3 of the casting frame, for storing molten metal W such as aluminum, and is for manufacturing the casting by tilting at a predetermined angle the casting frame and the molten metal storage device to pour the molten metal in the molten metal storage device via the runner of the casting frame into a hollow part 4 in the casting frame. Lifting drive devices 5 such as a hydraulic cylinder and a drive motor are installed on a bottom surface of the molten metal storage device, the molten metal storage device is configured to be lifted by driving the lifting drive device. At least at the start of tilting of the molten metal storage device, the vertical position of the molten metal storage device is adjusted so that a distance x between a lower part 3a of the runner of the casting frame and a bath level Wh of molten metal in the molten metal storage device is always within a constant range.

Description

  The present invention relates to a tire molding die manufacturing apparatus and a manufacturing method thereof, and more particularly, a tire molding die capable of improving the quality of a cast product of a tire molding die by a gypsum casting method. The present invention relates to a manufacturing apparatus and a manufacturing method thereof.

  Conventionally, as shown in FIGS. 5A to 5C, as a casting method of a tire molding die by a plaster casting method, a molten metal such as aluminum is adjacent to the casting frame 1 of the tire molding die. A container-shaped hot water storage device 2 for storing W is installed horizontally (0 °) (FIG. 5A), and after the molten aluminum metal W is stored in the hot water storage device 2, the casting frame 1 and the hot water storage device 2 is gradually tilted (FIG. 5 (b)), and the aluminum molten metal W in the hot water reservoir 2 is injected and filled from the runner 3 of the casting frame 1 into the cavity 4 in the casting frame 1. A tilt casting method (gravity casting method) is performed to complete the filling when 1 and the hot water sump device 2 are approximately 90 ° (vertical direction with respect to a horizontal installation surface) (FIG. 5C). (For example, refer to Patent Document 1).

  When the molten aluminum metal W is poured and filled into the casting frame 1 by the above method, there is a problem that the casting quality is deteriorated if the filling speed is high. In other words, the molten aluminum metal W passes from the inside of the hot water reservoir 2 through the runner 3 of the casting frame 1 and is filled into the product portion. In the case of an aluminum material (AC7A) in which (cavities) are generated and easily oxidized, defects in the oxide film are remarkable.

  However, there are cases where the filling speed cannot be adjusted only by the tilting speed of the casting frame 1 and the hot water sump device 2 as described above. For example, as shown in FIGS. When the amount of molten aluminum W is large, the molten aluminum W is gradually dropped and filled into the runner 3 of the casting frame 1 without increasing the tilt angle α (tapping angle) from the beginning. However, as shown in FIGS. 7A and 7B, when the amount of molten aluminum W in the hot water storage device 2 is small, the water level is low, and the tilt angle α Even if the tilt angle is increased and the tilting speed is decreased, the falling speed of the casting frame 1 in the runner 3 is increased, the filling speed into the casting frame 1 is increased, and the casting quality as described above is deteriorated. There was a problem.

  In general, the tilt angle α (tapping angle) from the inside of the hot water reservoir 2 is preferably 20 ° or less. Although it is necessary to manufacture the hot water storage device 2 corresponding to each amount of hot water, since there are many types (sizes) of molds, there are various types of casting frames. As a result, the number of hot water sump devices 2 also tends to increase, and sharing is desired.

JP-A-11-291022

  The present invention pays attention to such a conventional problem, and in the tilting casting method, the angle at which the hot water is discharged from the hot water storage device is constant regardless of the amount of the molten metal in the hot water storage device, and the oxide film of the casting product or the inside of the product. An object of the present invention is to provide a tire molding die manufacturing apparatus and a manufacturing method thereof which can prevent the formation of nests and can improve the quality of a cast product of the tire molding die.

  In order to achieve the above object, the present invention provides a tire molding die casting apparatus in which a hot water sump device is configured to be movable up and down via a lift drive device, and at least when the tilting device starts to tilt, The gist is that the vertical position of the hot water reservoir is adjusted so that the distance between the lower part of the runner of the frame and the molten metal surface of the hot water reservoir is always within a certain range.

  Here, the portion of the casting frame that contacts the molten metal in the side wall portion of the runner is made of a refractory material, and is connected to an elevating drive device of the sump device at the top of the sump device, and the sump. A non-contact type hot water detection device for detecting the amount of molten metal in the apparatus is installed, and the elevator drive device is operated according to the amount of molten metal in the hot water reservoir, The gist is that the distance between the molten metal surface of the hot water reservoir and the molten metal is always controlled within a certain range.

  Further, in the casting method of the tire molding die according to the present invention, the distance between the lower part of the runner of the casting frame and the molten metal surface of the sump device is always within a certain range at least when the sump device starts tilting. Thus, the gist of the invention is to adjust the vertical position of the hot water storage device via an elevating drive device and to adjust the tapping angle without being influenced by the amount of molten metal in the hot water storage device.

  Here, the portion that contacts the molten metal of the side wall portion of the runner side of the casting frame is made of a refractory material, preventing a decrease in the melting temperature by the refractory material at the start of tilting or pouring of the hot water storage device, In addition, a non-contact type hot water detection device that detects the amount of molten metal in the hot water storage device is installed at the top of the hot water storage device, and this hot water detection device detects the amount of molten metal in the hot water storage device, The detection device activates the raising and lowering drive device of the sump device according to the amount of hot water at the start of tilting of the sump device or at the start of pouring, so that the lower part of the runner of the casting frame and the molten metal surface of the sump device The gist is to control the distance to be always within a certain range.

Since the present invention is configured as described above, the following excellent effects can be obtained. (A). The sump device can be moved up and down via the lift drive device, and the distance between the bottom of the casting frame runner and the molten metal surface of the sump device is always maintained at least when the sump device starts to tilt. Since the vertical position of the hot water storage device is adjusted so that it is within a certain range, the discharge angle can be controlled to be constant regardless of the amount of molten metal in the hot water storage device. This is effective in preventing the formation of nests in the oxide film or inside the product and improving the quality of the cast product of the tire molding die.
(B). There is no need to prepare many hot water sump devices according to the type of casting frame, and the cost can be reduced.
(C). The amount of molten metal in the sump device is detected by a non-contact type water amount detection device, and the raising / lowering drive device of the sump device is operated according to the amount of hot water at the start of tilting or pouring of the sump device, and casting. Since the distance between the lower part of the runner of the frame and the molten metal surface of the hot water storage device is always kept within a certain range, the hot water discharge angle of the hot water storage device can be accurately controlled without human intervention. It is possible to prevent deterioration of casting quality.

FIG. 5 is a cross-sectional explanatory view when the amount of molten metal in the hot water sump device of the tire molding die embodying the present invention is large. It is a section explanatory view when the amount of molten metal in the hot water sump device of the mold for tire molding which implemented this invention is small. It is sectional drawing of the metal mold | die for tire molding which shows 2nd Embodiment of this invention. It is sectional drawing of the metal mold | die for tire molding which shows 3rd Embodiment of this invention. (A)-(c) is process explanatory drawing of the conventional tilting type casting method (gravity casting method). (A), (b) is explanatory drawing of the tilting type casting method when there are many amounts of the conventional molten metal. (A), (b) is explanatory drawing of the tilting type casting method with few conventional molten metal amounts.

  Hereinafter, embodiments of the present invention will be described 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 is a cross-sectional explanatory view of a hot water sump device when the molten metal amount of the hot water sump device 2 of a tire molding die embodying the present invention is large, and FIG. 2 is a sump of the tire mold die embodying the present invention. The cross-sectional explanatory drawing when the amount of molten metal in the apparatus is small is shown. The mold for molding the tire is a casting frame 1 for molding a cast product, aluminum installed adjacent to the runner 3 of the casting frame 1, etc. The molten metal W is stored in a container-shaped hot water storage device 2, and the casting frame 1 and the hot water storage device 2 are tilted by a predetermined angle so that the molten metal W in the hot water storage device 2 is heated in the hot water of the casting frame 1. A casting is manufactured by injecting and filling the cavity 4 in the casting frame 1 through the road 3.

  In the embodiment of the present invention, an elevating drive device 5 such as a hydraulic cylinder or a drive motor is installed on the bottom surface of the hot water sump device 2, and the elevating drive device 5 is driven to move the hot water sump device 2 up and down. To do.

  That is, at least at the start of tilting of the hot water reservoir 2, the distance x between the lower part 3 a of the runner 3 of the casting frame 1 and the hot water surface Wh of the molten metal W in the hot water reservoir 2 is always within a certain range, for example, within 40 mm. Preferably, the vertical position of the hot water sump device 2 is adjusted to be within 20 to 30 mm.

  When the distance x between the lower part 3a of the runner 3 and the molten metal W surface Wh in the hot water storage device 2 exceeds 40 mm, the tilt angle α (tapping angle) of the hot water storage device 2 increases, There is a problem that the falling speed is increased, the filling speed into the casting frame 1 is increased, and the casting quality is deteriorated. If the distance x is less than 20 mm, the lower portion 3a of the runner 3 and the hot water storage device 2 This is because, when the molten metal surface Wh becomes too close and the molten metal is poured into the hot water storage device 2, there is a problem that the molten metal flows into the hot water passage 3 if excessively poured.

  Accordingly, the distance x is preferably set or adjusted to be within 20 to 30 mm in consideration of casting quality.

  Next, FIG. 3 shows a sectional view of a tire molding die showing a second embodiment of the present invention. This embodiment is a portion in contact with the molten metal W in the side wall portion of the runner 3 of the casting frame 1. 3x is composed of a refractory material 6 such as alumina silica-based ceramic fiber.

  That is, when the molten metal W touches the metal casting frame 1, the melting temperature is lowered, which causes a problem when the molten metal W is filled. Therefore, the side wall portion of the casting frame 1 in contact with the molten metal W is kept warm. By installing a flexible refractory, problems during casting are prevented in advance.

  It is also possible to exert effects such as adjustment of the solidification rate of the molten metal by applying a predetermined thickness of an aluminum casting coating material to a portion of the metal casting frame 1 that contacts the molten metal W.

  The components of the coating material are, for example, sodium silicate: 15-20%, vermiculite: 3-8%, mica: 8-13%, bentonite: 1-5%, pure: 65-70%.

  FIG. 4 is a cross-sectional view of a tire molding die showing a third embodiment of the present invention. This embodiment is connected to the elevating drive device 5 at the upper part of the hot water sump device 2 and is connected to the hot water sump. A non-contact type hot water level detection device 7 such as a hot water level sensor for detecting the hot water level of the molten metal W in the apparatus 2 is installed. , The distance is calculated from the reflected light Q, and the hot water level is detected. Based on the value detected by the hot water detector 7, an output signal is output to the elevating drive 5, and the hot water reservoir 2. The elevation drive device 5 is operated according to the amount of molten metal W in the molten metal W, and the distance x between the lower part 3a of the runner 3 of the casting frame 1 and the molten metal W surface Wh in the hot water reservoir 2 is always constant. Is controlled to be within (40 mm).

  The present invention is configured as described above, and the casting frame 1 and the hot water sump device 2 are tilted at a predetermined angle so that the molten metal W in the hot water sump device 2 passes through the runner 3 of the casting frame 1. When pouring and filling the inside, that is, at least when the tilting device 2 starts to tilt, the distance x between the lower part 3a of the runner 3 of the casting frame 1 and the molten metal W surface of the molten metal W in the sump device 2 is always within 40 mm. Preferably, the vertical position of the hot water storage device 2 is adjusted by operating the elevating drive device 5 so that it is within 20 to 30 mm, and tilted without being affected by the amount of molten metal W in the hot water storage device 2. This is a casting method for adjusting the angle α (the tapping angle).

  As a result, it is possible to control the angle at which the hot water is discharged regardless of the amount of molten metal in the hot water storage device 2 (the hot water angle α). It is possible to improve the quality of a cast product of a tire molding die.

  Further, according to the present invention, the amount of molten metal in the hot water storage device 2 is detected by the non-contact type hot water detection device 7, and the hot water storage device 2 is detected according to the amount of hot water when the hot water storage device 2 starts to tilt or starts pouring. Since the elevating drive device 5 is operated to control the distance x between the lower portion 3a of the runner 3 of the casting frame 1 and the molten metal W level of the molten metal W of the hot water storage device 2 so as to be always within a certain range. The angle α at which the hot water is discharged from the apparatus 2 can be accurately controlled without manual intervention, and the casting quality can be prevented from deteriorating.

  Moreover, in this embodiment, the trouble at the time of casting is prevented beforehand by installing a refractory having a heat retaining property on the side wall portion of the casting frame 1 in contact with the molten metal W.

  In the present invention, particularly in the tilt type gravity casting apparatus and casting method, the angle of pouring (the pouring angle α) is controlled to be constant regardless of the amount of molten metal in the hot water sump apparatus 2, so that the oxide film of the casting product and the inside of the product are contained. It is possible to prevent the formation of nests and improve the quality of a cast product of a tire molding die.

DESCRIPTION OF SYMBOLS 1 Casting frame of mold for tire molding 2 Hot water storage device 3 Runway 3a Lower part of runway 4 Cavity 5 Lifting drive device 6 Refractory material 7 Hot water detection device W Molten metal α Tilt angle (tapping angle)
Wh Hot water surface x Distance Q Reflected light

Claims (6)

The casting frame and a hot water reservoir device for accumulating molten metal installed adjacent to the runner of the casting frame, and tilting the casting frame and the hot water reservoir device at a predetermined angle to move the molten metal in the hot water reservoir device. In a casting apparatus for a mold for molding a tire to be injected and filled into a casting frame through a runner of the casting frame,
The hot water sump device is configured to be movable up and down via a lift drive device, and the distance between the bottom of the casting frame runner and the molten metal surface of the hot water sump device is always constant at least when the tilting device starts to tilt. A casting apparatus for a mold for molding a tire, wherein the vertical position of the hot water sump device is adjusted so as to be within the range.   The tire casting die casting apparatus according to claim 1, wherein a portion of the casting frame that contacts the molten metal on the side wall of the runner is made of a refractory material.   A non-contact type hot water detection device connected to the raising and lowering drive device of the hot water storage device and detecting the amount of molten metal in the hot water storage device is installed at the upper part of the hot water storage device. 3. The lift driving device is operated according to the amount of hot metal, and the distance between the lower part of the runner of the casting frame and the molten metal surface of the hot water storage device is always controlled within a certain range. The casting apparatus of the tire mold as described. In the casting method of the mold for tire molding in which the casting frame and the hot water storage device are inclined at a predetermined angle, and the molten metal in the hot water storage device is injected and filled into the casting frame through the runner of the casting frame,
At least at the start of tilting of the sump device, the vertical position of the sump device is set via an elevating drive device so that the distance between the lower part of the runner of the casting frame and the molten metal surface of the sump device is always within a certain range. And adjusting the tapping angle without being affected by the amount of molten metal in the hot water storage device.   5. The portion of the casting frame that contacts the molten metal in the side wall portion of the runner is made of a refractory material, and the melting temperature is prevented from being lowered by the refractory material at the start of tilting or pouring of the hot water storage device. A method for casting a tire molding die as described.   A non-contact type hot water detector that detects the amount of molten metal in the hot water reservoir is installed at the top of the hot water reservoir, and this detector detects the amount of molten metal in the hot water reservoir. By operating the raising / lowering drive device of the sump device according to the amount of hot water at the start of tilting or pouring of the sump device, the distance between the lower part of the casting frame runner and the molten metal surface of the sump device is adjusted. A method for casting a mold for molding a tire, which is controlled so as to be always within a certain range.

Images