JPH0788620A - Trough type molten metal supplying device - Google Patents

Abstract

PURPOSE:To make the closeness perfect by making a valve rod rotatably and hanging down a valve rod to the lower part of a cylinder with a floating joint after completing closed movement to absorb the difference between thermal expansion rates. CONSTITUTION:A weighing valve rod 26 is vertically moved to open/close the sealing surface 27a of a valve seat sleeve 27 and molten metal 15a is poured into an injection sleeve 3. After pouring the molten metal, the valve rod 26 is descended by action of an air cylinder 72 and abutted on the sealing surface 27a. The valve 26 is rotated with an air motor 62 and the foreign matter stuck to the sealing surface 27a is removed to perfectly seal the molten metal 15a. As the valve rod 26 and the air motor 62 as a valve part rotation driving device are hung down to the air cylinder 72 through the floating joint 71, the difference between the thermal expansion rates caused by temp. differences between a trough cover part 12 and a trough part 11 is absorbed and high centripetal action is given and the closeness of the sealing surface 27a can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gutter type hot water supply device for supplying a molten metal of an aluminum alloy or the like to an injection sleeve of a die casting machine using a gutter.

[0002]

2. Description of the Related Art Conventionally, when supplying molten metal to an injection sleeve of a die casting machine, for example, Japanese Patent Publication No. 60-2
As described in Japanese Patent No. 5220, a dedicated molten metal holding furnace is arranged near the die casting machine, and the holding furnace measures and conveys the molten metal and pours the molten metal. For measuring / conveying and pouring methods, refer to Japanese Patent Publication No. 60-2522.
As described in Japanese Unexamined Patent Publication No. 0, a method using a ladle and a method of pumping a pipe by an electromagnetic induction pump have been mainstream in practical use.

However, each of these has the following drawbacks. (1) Ladle method: The molten metal is exposed to the outside air and is oxidized, and the temperature is lowered. (2) Electromagnetic induction pump method: Since the molten metal driving force of the electromagnetic pump is weak, the measuring accuracy is poor. Further, in order to increase the molten metal propulsion force, the power supply device becomes large in scale, and the cost and space are deteriorated. Further, the cost also increases for the thermal expansion correspondence and maintenance of the pressure feeding pipe. Further, as a common drawback, a dedicated molten metal holding furnace becomes redundant, which lowers productivity.

The die casting industry is also a representative of workplaces with a bad working environment. The main causes are scattering of the mold release agent and heat dissipation of the molten metal holding furnace and its peripheral equipment. The following are the current problems with molten metal operation. (1) A large-capacity holding furnace is installed on the side of the die casting machine, and moreover, a large amount of heat is dissipated. (2) The mechanism of the hot water supply device is mainly an open type, and a large amount of heat was dissipated to the work place. (3) As a result of (1) and (2), not only the working environment is deteriorated, but also the thermal efficiency is deteriorated. To solve this problem, a small capacity, closed gutter type continuous furnace and a highly accurate metering valve device are required.

By the way, the valve type hot water supply method has not been put to practical use in the die casting industry. The main reasons for this are as follows. (1) The main method was to hold a large amount of molten metal on the side of the die casting machine. As a result, there was no valve mechanism that could withstand the high temperature atmosphere. (2) The measurement accuracy varied due to changes in the properties of the molten metal, and it was not practical.

Therefore, in order to solve these problems, the applicant company of the present invention, for example, like the invention of Japanese Patent Application No. 4-272212 which has not been published at the time of the present application, the tip of the gutter for hot water distribution. A gutter-shaped box that can be sealed is placed between the pouring port of the injection sleeve and the injection sleeve. By the siphon action of the inverted U-shaped tube provided between the tip of the hot water distribution gutter and the rear end of the gutter box, the hot water distribution gutter is automatically moved into the gutter box, As the pouring valve device, a valve seat of the drain port and a valve rod that is openable and closable with respect to the valve seat are used, and the molten metal is intermittently and quantitatively supplied from the metering pouring valve device into the injection sleeve of the die casting machine. Invented a gutter type water heater.

Japanese Patent Application No. 4-272212 has a structure as shown in FIG. In FIG. 2, reference numeral 1 denotes a hot water distribution gutter, which is also called a launder system gutter capable of unmanned hot water distribution, and usually has a molten metal receiving port on one side, depending on the number and position of die casting machines from the middle. It has a branch part. In FIG. 6, reference numeral 1 shows only the tip of this branched portion. A gutter-shaped box 2 is provided so as to be swingable around the tip of the hot water distribution gutter 1 and the vicinity of the tip of the hot water distribution gutter 1 so that the inside can be hermetically sealed. . 3 is an injection sleeve of a die casting machine, 3a is a pouring port, 4 is a plunger tip slidably provided in the injection sleeve 3, and 5 is a plunger.

The gutter-shaped box body 2 is provided so as to be vertically swingable around the swing center portion 6 between, for example, an original position in a horizontal state and an inclined position in which θ = 15 degrees is lifted. Has been. Reference numeral 7 is a cylinder for vertically swinging the gutter-shaped box body 2. 8 is a stopper for adjusting the horizontal position which is the lower limit position, and 9 is a frame. The gutter-shaped box body 2 is inclined so as not to interfere with the maintenance of the injection sleeve 3 and the plunger tip 4 and to return the molten metal from the gutter-shaped box body 2 to the gutter 1. In addition, the gutter-shaped box body 2 is designed to be movable also in the horizontal direction.

Generally, the gutter-shaped box body 2 constituting the gutter type water heater arranged between the most distal end of the hot water distribution gutter 1 which is a fixed gutter and the injection sleeve 3 is mainly composed of the gutter part 11, It is composed of a gutter lid 12, and an injection sleeve 3 is provided near the tip of the gutter-shaped box body 2.
Metering pouring valve device 1 located directly above the pouring port 3a
3, and an inverted U-shaped pipe device 14 is provided on the hot water distribution gutter 1 side. The gutter part 11 is composed of a tank member 16 that comes into contact with the molten metal 15a, a heat insulating member 17 that keeps it warm, and a box body 18 that stably holds these.

The gutter lid 12 includes a heat retaining member 19 and an exterior member 20.
A heater 21 is attached to the inside of the heat retaining member 19 for retaining or heating the melt 15a in the A chamber, which is the melt passage or the melt reservoir. Besides,
The gutter lid portion 12 has the same drive mechanism 22 as a rotary / linear motion converting mechanism using a ball screw of the metering pouring valve device 13, a servomotor 23, and a reflection type photoelectric tube type molten metal surface sensor 24 for control data. A temperature sensor 25 is attached. Reference numeral 24a is a molten metal level signal generator, and 25a is a molten metal temperature signal generator. On the other hand, the metering pouring valve device 13 includes a servo motor 23, a drive mechanism 22, a ceramic metering valve rod 26, a ceramic valve seat sleeve 27, a heater 28,
It is composed of a guide pipe 29 and the like. Valve seat sleeve 27
Is embedded from the inner surface of the tank member 16 toward the bottom of the heat retaining member 17, and the valve seat sleeve 2 inside the heat retaining member 17 is embedded.
A heater is embedded in the outer periphery of 7. The top end of the metering valve rod 26 can be moved up and down with a rotating motion so that it can come into contact with or separate from the lower end hole of the valve seat sleeve 27.
It is opened and closed. The servomotor 23 receives the pouring instruction and is controlled by the control device according to various information so that accurate measurement is performed.

The inverted U-shaped tube device 14 has an inverted U-shape whose ends are respectively located in the lower part of the A chamber in the gutter-shaped box body 2 and in the lower part of the B chamber, which is the molten metal passage in the hot water distribution gutter 1. It is composed of a tube 30 and a heater 31 of an electromagnetic induction system that heats and heats the tube 30 from the surroundings, is fixed to the gutter portion 11, and moves integrally when the entire gutter box body 2 swings. In the heat retaining member 32 portion of the hot water distribution gutter 1, the space 33 provided around the inverted U-shaped tube 30 is a movement allowance at this time. The inverted U-shaped pipe device 14 allows the molten metal 15b to pass through and move the entire hot water supply device.

A heat insulating material 35 is arranged between the gutter-shaped box body 2 and a part of the hot water distribution gutter. The heat insulating material 35 is preferably elastic, such as ceramic wool. This is because the gap changes due to the swing of the main body. 36 is a gas exhaust passage provided in the heat retaining member 19, 37 is a suction pressurizing device which is also a pressurizing / depressurizing device, 38 is a passage for an inert gas provided in the heat retaining member 19, 38a is an opening / closing valve, 39 is an inert gas It is a supply device.

FIG. 3 shows the metering pouring valve device 13 in detail, so that the tip of the ceramic metering valve rod 26 can come into contact with or separate from the lower end hole of the ceramic valve seat sleeve 27. It is installed so that it can move up and down and open and close. The upper end portion of the metering valve rod 26 is connected to the shaft 41 via a coupling portion 40 having a screw portion, a taper portion, or the like.

The coupling portion 40 is required to have a function of reliably holding the metering valve rod 26 in the high temperature atmosphere without misalignment. The metering valve rod 26 is inserted into the lower end of the holding rod 40a, and is securely held by the tapered portion 40c of the outer sleeve 40b.
An adjusting nut 54 is provided above the holding rod 40a to generate a constant surface pressure on the tapered portion 40c. Therefore, the coupling 55 and the outer sleeve 40b are provided on the upper surface 54a of the nut.
Causes a predetermined force to be applied. On the other hand, the coupling 55
Is keyed to the shaft 41, the rotational reciprocation of the shaft 41 can be transmitted to the metering valve rod 26.

Reference numeral 42 denotes a cylindrical body fixedly attached to a bracket 43 attached to the gutter lid portion 12.
A ball screw 44 is provided between the outer peripheral surface of the shaft 42 and the inner peripheral surface of the cylindrical body 42, and the shaft 41 is rotatable and vertically movable. 2 is a belt pulley with teeth attached to the upper end of the shaft 41, and 46 is a belt with teeth.
It is connected to the servo motor 23 which is a pulse motor shown by. Since the tubular body 42 is a fixed portion, the shaft 41, the belt pulley 45, and the like move up and down by about 15 mm while rotating. In this case, since the belt 46 is flexible,
The belt pulley 45 can be moved up and down to some extent. Therefore, the metering valve rod 26 is structured to rotate even during the valve opening / closing operation. The rotation of the metering valve rod 26 is carried out in order to remove foreign matter adhering to the valve sealing surface 27a and to make the metering valve rod 26 have an automatic centripetal property. The servo motor 23 receives a pouring command and the like,
It is controlled by various information so that accurate measurement can be performed.

Next, the operation in this example will be described step by step. 1. State at the start of operation (see FIG. 2) (1) A state in which the molten metal 15b is contained in the chamber B as shown in the figure, but there is no molten metal 15a in the chamber A closed by the metering pouring valve device 13 Then, the inert gas fills the A chamber through the on-off valve 38a and the passage 38. No molten metal has yet entered the inverted U-shaped tube 30. (2) The suction pressurizing device 37 is operated to reduce the pressure in the chamber A to a pressure corresponding to H, and the molten metal 15b is passed through the inside of the inverted U-shaped tube 30 and sucked into the chamber A. (3) Once the flow starts, the suction is stopped, and even if the pressure is released to the atmosphere, the siphon causes the molten metal to flow at a differential pressure of h with respect to the surface of the molten metal 15b. This differential pressure h does not change until the surface of the molten metal 15a rises and reaches the lower surface of the inverted U-shaped tube 30. After reaching, the liquid level of the molten metal 15a rises with a differential pressure of Δh, and when Δh = 0, that is, when the liquid levels of the molten metals 15a and 15b become the same height, the molten metal 15a passing through the inverted U-shaped tube 30 Flow stops. (4) At this point, the servo motor control device (not shown) takes in the values of the melt surface sensor 24 and the temperature sensor 25, and waits for a pouring start signal together with other setting data such as the pouring amount.

2. Operation during production operation (normal) (1) In response to a pouring command from the die casting machine main body, the servo motor 23 is activated and the metering valve rod 26 is raised, whereby the valve is opened and the molten metal 15a is injected into the injection sleeve 3 It begins to flow in. (2) After a lapse of a predetermined time, the control device lowers the metering valve rod 26, the valve is closed, and the pouring is completed. When the metering valve rod 26 is lowered, by rotating the metering valve rod 26 about its axis, foreign substances adhering to the sealing surface of the valve seat sleeve 27 can be removed and a centripetal action can be given to the metering valve rod 26. The sealing effect becomes more stable.

(3) In this case, the temperature of the molten metal 15b in the B chamber is set to the minimum temperature T _B required for hot water distribution, and the temperature of the molten metal 15a in the A chamber is set to T _A required for casting, T _A
Carry out the operation in relation to> T _B. Therefore, the temperature of the molten metal 15a is set to a desired temperature by the action of the electromagnetic induction type heater 31 and the heater 21 that can be quickly heated. This is B
If the molten metal 15b in the room is high, a large amount of an oxide film is likely to be generated on the surface, or the molten metal may deteriorate, resulting in deterioration of quality. This is because only 15a has a necessary temperature.

(4) Further, as the heater 31 of the inverted U-shaped tube 30, an electromagnetic induction type heater is used to heat the molten metal inside and to apply the thrust in the flow direction to the molten metal inside to make the molten metal 15b in the B chamber A Move it to the room as quickly as possible. (5) In the metering control, the valve opening degree or the valve opening time of the metering pouring valve device 13 is determined based on one or more data among the molten metal surface position in the chamber A, the molten metal temperature, the molten metal viscosity, and the material characteristics of the molten metal. The amount is increased / decreased so that the amount poured into the injection sleeve 3 and the liquid surface of the molten metal 15a in the chamber A before pouring are the same each time. (6) In this case, the metering valve rod 2 is used as the monitoring value of the valve closed state.
The lower limit position error amount of 6 may be used, or the abnormal current value of the servo motor 23 may be used. (7) When the pouring is completed, an injection command is issued to the die casting machine body to complete one cycle.

[0020]

In the example shown in FIGS. 2 and 3, as described above, the metering pouring valve device 13 has a drive mechanism 22, a servomotor 23, which is a rotation / linear motion converting mechanism using a ball screw. Ceramic metering valve rod 26
Etc., and is provided so that it can be moved up and down with rotation and can be opened and closed, but this has the following drawbacks. (1) The drive mechanism 22 is fixedly attached to the bracket 43 attached to the gutter lid portion 12, and the ceramic valve seat sleeve 27 that abuts the metering valve rod 26 that is vertically moved and opened / closed by the drive mechanism 22 is the gutter portion. Since it is fixedly embedded in 11, the misalignment occurs between the metering valve rod 26 and the valve seat sleeve 27 due to the difference in the amount of thermal expansion due to the temperature difference between the gutter lid part 12 and the gutter part 11. Since it is guided by the ball screw nut portion 42, misalignment cannot be absorbed and the molten metal sealability when the metering valve is closed is poor. (2) Since the metering valve rod 26 is driven by a ball screw, the rotation is stopped when it comes into contact with the valve seat sleeve 27. Therefore, the foreign matter and the like adhering to the valve seat sleeve 27 cannot be sufficiently removed, and the molten metal is completely sealed. It may not be possible to

[0021]

In order to eliminate these disadvantages, in the present invention, a valve seat portion provided at the lower end of the tip,
In a gutter type hot water supply device provided with a valve rod that can be opened and closed freely with respect to the valve seat portion, a valve portion rotation mechanism is provided on the axis of the valve rod to rotate the valve rod after completion of the closing operation. In addition to the structure, the valve portion rotating mechanism and the valve rod are integrally hung below the cylinder through a floating joint, and the valve rod is provided so as to be openable and closable by the vertical movement of the cylinder.

[0022]

Operation: The metering valve rod closes after pouring a predetermined amount of molten metal into the injection sleeve, but starts rotating when the metering valve rod comes into contact with the valve seat sleeve, and the valve seat sleeve and the metering valve Stop when foreign substances and the like adhering between the seal surfaces of the rod are removed, or rotate until the opening operation for the next pouring starts. Therefore, it is possible to prevent the molten metal from leaking from the sealing surface during the closing operation.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment of the present invention is an improvement of a part of that shown in FIG. 2. Therefore, the whole view and its description are omitted, and only the improved part is shown enlarged in FIG. . As shown in FIG. 1, a metering pouring valve device 50 provided at the tip of the gutter-shaped box body 2 includes a metering valve rod 26, a valve seat sleeve 27, a guide pipe 29 forming a tubular partition wall, a coupling 60, and a connection. Rod 61, air motor 62, guide device 63, gap 6
5, a connecting shaft 66, a flex coupling 67, a floating joint 71 and an air cylinder 72.

In this embodiment, an air motor 62 for rotationally driving the metering valve rod 26 and an air cylinder 72 for vertical movement.
Are arranged in tandem so that they are located on the same axis as the metering valve rod 26 via the connecting means, respectively, and then the air cylinders 72 are attached to the support box 75 having both side surfaces opened.
It is configured to be hung below a floating joint 71 mounted on a rod 72a of an air cylinder 72.

A predetermined amount of molten metal 15a is poured into the injection sleeve 3 (opening operation), pouring is stopped (closing operation), and it is rotated after coming into contact with the valve seat sleeve 27 (turning operation). The metering valve rod 26 that has been
Is connected to the connecting rod 61 by means of a connecting shaft 66 and a flex coupling 67 on the same axis line to an air motor 62 which is a valve portion rotation driving device. Connecting rod 61
Is guided by a bush 64 incorporated in the guide device 63, but a gap 65 is formed between the connecting rod 61 and the bush 64 to the extent that the difference in thermal expansion amount due to the temperature difference between the trough lid portion 12 and the trough portion 11 can be absorbed. It is provided.

The bracket 68 to which the air motor 62 is attached is connected to a floating joint 71 having an automatic centering mechanism via a tie rod 69 and a connecting plate 70.
It is suspended by an air cylinder 72.

Further, the tip end portion 26a of the metering valve rod 26 is formed in a hemispherical shape, while the sealing surface 27a of the valve seat sleeve 27 is tapered so that the tip end portion 26a of the metering valve rod 26 is formed.
And the sealing surface 27a of the valve seat sleeve 27 is
When the two are brought into contact with each other by the closing operation, the contact between them becomes a line contact. Therefore, the rotating torque is small, and foreign matter such as an oxide film can be easily removed.

When the drive mechanism at the upper end of the metering valve rod 26 is structured as described above, the shaft center does not change even if the temperature of the metering valve rod 26 changes significantly, and in addition, 26 has the effect of operating smoothly.

The pouring work with the above configuration will be described. Figure 1
Shows a state in which the metering valve rod 26 is lowered by the action of the air cylinder 72 and abuts on the sealing surface 27a of the valve seat sleeve 27 after pouring into the injection sleeve 3 for a predetermined time.
In this state, while rotating the metering valve rod 26 by the air motor 62, the semi-solidified material such as aluminum or the foreign matter such as oxide adhering to the sealing surface 27a of the valve seat sleeve 27 is removed to completely seal the molten metal 15a. Of. After that, the metering valve rod 26 may be continuously rotated until the molten metal 15a is poured into the injection sleeve 3, or may be rotated for a certain period of time and stopped when it is considered that the foreign matter is removed. May be.

[0030]

As is apparent from what has been described above, in the present invention, the valve seat portion provided at the lower end of the tip and the valve rod that is movable up and down with respect to the valve seat portion are provided. In the gutter type hot water supply device, a valve rotating mechanism is provided on the axis of the valve rod so that the valve rod can be rotated after completion of the closing operation, and the valve rotating mechanism and the valve rod are integrally floated. The valve rod is hung down below the cylinder via a joint, and the valve rod can be opened and closed by the vertical movement of the cylinder, so that the foreign matter adhering to the sealing surface when the valve rod is closed rotates with the pressing force of the valve rod. The valve seat and the valve stem can be easily sealed because they only need to be rotated until they are ground and removed by. In addition, a floating joint with an automatic alignment mechanism is provided, and a gap is provided in the guide part to absorb the difference in thermal expansion amount due to the temperature difference between the gutter lid part and the gutter part. It is possible to give a higher centripetal action. Further, by providing the valve portion rotating mechanism directly on the axis of the valve portion, the belt is unnecessary and the durability of the device is improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part showing an embodiment of an apparatus of the present invention.

FIG. 2 is an overall vertical sectional view showing an example of a conventional device.

3 is a vertical cross-sectional view of a main part of the conventional device shown in FIG.

[Explanation of symbols]

 1 gutter for hot water distribution 2 gutter-shaped box body 3 injection sleeve 8 stopper 13, 50 metering pouring valve device 14 inverted U-shaped pipe device 15a, 15b molten metal 21, 28 heater 22 drive mechanism 23 servo motor 24 molten metal surface sensor 25 temperature sensor 26 metering valve rod 27 valve seat sleeve 27a sealing surface 30 inverted U-shaped tube 31 heater (electromagnetic induction type) 37 suction pressurizing device 39 inert gas supply device 40 coupling part 44 ball screw 46 belt 55, 60 coupling 61 connection Rod 62 Air motor 67 Flex coupling 69 Tie rod 71 Floating joint

Claims (1)

[Claims] 1. A trough type hot water supply apparatus comprising a valve seat portion provided at a lower end of a tip and a valve rod that can be opened and closed with respect to the valve seat portion, wherein the valve portion rotates on an axis of the valve rod. A mechanism is provided to make the valve rod rotatable after the closing operation is completed, and the valve portion rotating mechanism and the valve rod are integrally hung below the cylinder via a floating joint to move the cylinder vertically. The gutter type hot water supply device is characterized in that the valve rod is provided so as to be openable and closable.