JPH03254355A - Vacuum casting device - Google Patents

Abstract

PURPOSE:To improve the productivity by providing a suction cover which has an opening part pierced with a suction hole communicating with the opening part on the lower face, placing it on the upper face of a sand mold and exhausting air and gas in the sand mold to the outside of the mold, and also, providing a suction cover placing device and a suction cover collecting device. CONSTITUTION:This device is provided with a suction cover 4 which has an opening part on the lower face, and in which the lower face peripheral edge part which comes into contact closely with the upper face of a sand mold, and suction holes 25, 26 communicating with the opening part are opened. In a suction cover placing position S1 positioned on the feed-in side against pouring positions S2, S5, a suction cover placing device 5 is provided on the upper face of the sand mold, in suction cover collecting devices S4, S7 positioned on the feed-out side, suction cover collecting devices 6, 7 for removing the suction cover 4 are provided. On the suction holes 25, 26 of the suction cover 4, suction cups 101, 102 are provided so as to be freely attachable and detachable. Also, between the pouring positions S2, S5 and solidification holding positions S3, S6 set onto its feed-out side, freely suckable suction devices 9, 10, 11, 12, 13 and 14 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to vacuum casting equipment for casting while sucking gas generated by thermal decomposition from a sand mold during sand casting.

(Prior art) When casting using a sand mold, the organic binder in the sand mold is burned by the molten metal and a large amount of gas is generated. It is discharged into the atmosphere through the vent hole.

However, if the gas is not sufficiently discharged, gas defects such as blowholes and pinholes will occur in the cast product.

Therefore, as disclosed in Japanese Unexamined Patent Publication No. 57-160565, a technique has been proposed in which the gas generated during casting is forcibly sucked in by a suction pump and discharged outside the mold.

(Problem to be Solved by the Invention) However, the above technique is performed by inserting a large number of suction pipes branched from a head pipe connected to a suction pump into a large number of gas vent holes. It is difficult to connect the suction pipe to the machine and requires manual labor, resulting in poor productivity. Furthermore, there is a problem in that mold parts are likely to warp around the gas vent hole during connection, and casting defects such as sand pits are likely to occur.

In particular, in mass production casting equipment where sand molds are transported intermittently at regular intervals in a 10 to 20 second cycle and molten metal is poured from a pouring device at the pouring position, suction means must be installed manually. is practically unfeasible.

The present invention has been made to solve this problem, and it is an object of the present invention to provide vacuum casting equipment that can perform vacuum casting even in mass production casting equipment without relying on manual work.

(Means for Solving the Problems) In the vacuum casting equipment of the present invention, which has been made to achieve the above object, a sand mold is transported intermittently at regular intervals, and a sand mold is transported to a pouring position s2. In the casting equipment in which the molten metal is poured into the sand mold from the pouring device 2.3 in S5, a suction hole is formed that has an opening on the lower surface, a lower surface peripheral portion that is in close contact with the upper surface of the sand mold, and communicates with the opening. A suction cover 4 with openings of 25° and 26 is provided, and suction is provided to place the suction cover 4 on the upper surface of the sand mold at a suction cover placement position S1 located on the feeding side in the conveying direction with respect to the pouring position S2°S5. A suction cover recovery device that includes a cover placement device 5 and removes the suction cover 4 from the top surface of the sand mold after solidification at the suction cover recovery positions S4 and S7 located on the sending side in the conveyance direction! 6.7 is provided, and the suction hole 25. of the suction cover 4 is provided.
Suction cups 101 and 102 are detachably attached to 26.
and the pouring position S2. Suction devices 9, 10 that can freely suck air between S5 and the coagulation holding machine positions S3 and S6 set on the delivery side thereof. The structure of the invention is that lL12, 13.14 are provided.

(Function) A suction cover is placed on the top surface of the sand mold by a suction cover placement device at the suction cover placement position of the sand mold that is intermittently conveyed at a constant pitch. As a result, the lower peripheral edge of the suction cover and the upper surface of the sand mold are in close contact with each other, and the upper surface of the sand mold defined by the peripheral edge is in communication with the suction cover opening. That is, simply by opening a gas vent hole at an arbitrary position on the divided upper surface of the sand mold, the gas vent hole and the suction cover opening are reliably communicated. It also communicates with the casting sand gap of the sand mold covered by the suction cover.

The sand mold with the suction cover 4 placed thereon is intermittently transported to the pouring position. Here, the suction cup of the suction device is attached to the suction hole of the suction cover. When suction is started, the air inside the sand mold is suctioned through the gas vent hole and the casting sand gap, and the casting cavity inside the sand mold can be brought into a reduced pressure state.

When molten metal is poured from the pouring device in this state, the molten metal quickly flows into the casting cavity under reduced pressure and fills it. At this time, gas generated by thermal decomposition by the molten metal passes through the gas vent hole and the casting sand gap, and is discharged outside the mold via the suction cover and suction device.

After pouring is completed, the sand mold is intermittently transported to the coagulation holding machine position. The suction device continues suction even at the solidification holder position until the sand mold solidification is completed. The suction cup is removed before the sand mold is transported from the coagulator position to an adjacent position intermittently.

Thereafter, when the sand mold is intermittently conveyed to the suction cover collection position, the suction cover on the top surface of the sand mold is removed by the collection device. Incidentally, the sand mold is further conveyed to a rear demolding position, where it is dismantled and the product is taken out.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 10.

FIG. 1 is an overall layout diagram of the vacuum casting equipment according to the embodiment, in which a mold 1 formed in a molding shop is placed along the direction of the arrow, at a suction cover mounting position S1, at a first pouring position S2, at a first pouring position S2, and at a first pouring position S2. Coagulation holding machine position S3, first suction cover collection position S4, second pouring position S5, second coagulation holding machine position S6, second suction cover collection position S7, and further to the frame disassembly field intermittently at regular intervals. transported. The mold 1 is placed on a pallet of a carrier, and the carrier is intermittently moved on a rail at a constant pitch by a pinch feeding means such as a hydraulic cylinder.

The first and second pouring positions S2. A first pouring device 2 and a second pouring device 3 are installed in S5.

At the suction cover placement position S1, a suction cover placement device 5 is installed for placing a suction cover 4 on the upper surface of the mold for suctioning air in the mold and gas generated during casting. On the other hand, the first and second suction cover recovery position fs4
．． At S7, first and second suction cover recovery devices 6 and 7 are installed for picking up and recovering the suction cover 4 on the mold.

The suction cover 4 collected by the collection devices 6 and 7 is
From the suction cover mounting position S1 to the second suction cover collection position S
Collection container hair 8 installed parallel to the mold conveyance line along 7
and is returned to the suction cover mounting device 5.

Then, the first pouring position S2 and the first coagulation holding machine position S3
a first fixed suction device 9 for suctioning air inside the mold 1 and gas generated during casting through the suction cover 4;
10 are provided. In addition, the first pouring position S2 and the first
A first movable suction device 11 is installed between the coagulation holding device position S3 and the first movable suction device 11, which can freely suck and move between the repositions. These devices 9, 10, 11 constitute a first suction device. Second pouring level Iss and second coagulation holding machine position S
6 and also in between the second fixed suction device 12.1
3 and a second movable suction device 14 are installed, and these devices 12, 13 degrees 14 move the second suction device to the tank bottom.

Details of the mold 1 and the suction cover 4 are shown in FIGS. 2 to 5.

The mold 1 includes an upper mold 44 in which an upper body type 43 is formed in an upper frame 42, a lower mold 47 in which a lower body type 46 is formed in a lower frame 45, and upper and lower body types 43 and 46. The upper and lower main bodies 43, 46 and the core mold 48 are formed by a sand mold such as a green mold or a dry mold.

A cavity 49 for product casting is formed between the upper and lower main body types 43, 46 and the core mold 48, and a runner 50 is formed in communication with the lower part of the cavity 49, and the runner 50 is connected to the upper main body type. 43 is opened as a pouring port 51 on the top surface.

The core mold 48 has a stepped cylindrical shape, and a gas vent hole 53 that is open to the periphery of the upper surface of the upper main body mold 43 is formed in the hollow portion 52 so as to communicate therewith. This mold 1 does not have a riser hole or a lift hole as in the conventional case.A cast iron suction cover 4 is removably placed in close contact with the center or lower upper surface of the upper main body 43. ing.

The inside of the suction cover 4 is divided into a peripheral space 22 and a central space 23 via a partition wall 24, and the lower surface of each space 22.23 is open and the upper surface of the upper main body 43 is opened. It's communicating. Gas vent hole 5 communicating with core mold 48
The opening 3 is opened at a position communicating with the lower opening of the peripheral space 22.

The lower surface of the partition wall 24 and the lower surface of the periphery of the suction cover 4 are in close contact with the upper surface of the upper main body 43, so that the upper surface of the upper main body 43 is divided into a concave peripheral area and a central area. Each area corresponds to each space 22 . of the suction cover 4 .
It communicates independently with the opening of 23. Note that the upper peripheral area where the pouring port 51 is open is outside the suction cover 4 and is exposed to the atmosphere.

24A is a sealing material, but it is not necessarily necessary.

A pair of suction holes 25 are provided in the upper part of the suction cover 4, each communicating with the peripheral space 22 and the central space 23.
．． Three sets of 26 are provided on the infeed side, central part, and outlet side of the mold.

An on-off valve 27 is attached to each of the suction holes 25 and 26. In FIG. 2, only one on-off valve 27 is depicted, and the others are omitted from illustration. The on-off valve 27 is connected to the suction hole 2
5.26 is attached to the main body 28, a valve body 29 for opening and closing the flow path of the main body 28, and a flow path inlet portion 32 of the valve body 29.
a spring 30 for biasing and closing the valve; and a valve rod 3 for separating the valve body 29 downward against the elastic force of the spring 30.
1, and the upper part of the valve stem 31 protrudes above the main body 28. Therefore, when no downward force is applied to the valve stem 31, the suction holes 25, 26 remain closed, and the valve stem 31
By pushing down, the suction holes 25, 26 and the flow path of the on-off valve 27 are brought into communication. At this time, by connecting suction means to the flow path outlet portion 33 of the on-off valve 27, each space 22, 23 inside the suction cover 4 is brought into a suction state.

Furthermore, an opening 34.35 for installing a safety valve, which communicates with each of the spaces 22 and 23, is provided in the upper part of the suction cover 4.
, 37 are attached by hinges and can be opened and closed freely. The lids 36, 37 are normally closed due to their own weight, and are opened when the pressure inside each space 22, 23 becomes equal to or higher than atmospheric pressure. 38 is a hanging fitting for handling the suction cover 4. 39 is a positioning pin that engages with the upper frame 42.

Next, the suction cover mounting bag W5 and the first and second suction cover collection devices 6.7 will be explained. These devices (referred to as suction cover transfer devices) have the same structure, and the first
The suction cover collecting device 6 will be explained based on FIG. 1, FIG. 6, and FIG. 7 as a representative example.

The suction cover transfer device includes a frame 60 constructed across the collection conveyor 8, a cart 63 having wheels 62 that can be moved freely on the upper and lower surfaces of a rail 61 attached to the frame 60, and a lower part of the cart 63. A lifting frame 65 that can be raised and lowered via an X-link 64, a clamping device 68 having hooks 66 and 67 that engage and disengage from the hanging fitting 38 of the suction cover 4, and the clamping device 68 are connected to the mold conveyance line and collected. A drive device 69 for moving the carriage 63 to and from the conveyor 8; and a hydraulically operated lifting cylinder 70 for raising and lowering the clamping device 68 between the carriage running level and the clamping level of the suction cover 4. It consists of

As shown in FIG. 7, the clamp device 68 has a frame 72 pivotally attached to a metal fitting 71 suspended from the front part of the lifting frame 65, and a pair of horizontal shafts 73, 74 at the bottom of the frame 72. A pair of hooks 66 and 67 that engage with the hanging fittings 38 of the suction cover 4 are fixed to the center of each of the horizontal shafts 73 and 74. At the front and rear parts of the frame 72, the shaft ends of the horizontal shafts 73 and 74 protrude, and a pair of clamp cylinders 75 and 76 composed of hydraulic cylinders are attached in opposite directions. Arms 77 fixed to the shaft ends are each pivotally connected. With this configuration, when the front clamp cylinder 75 and the rear clamp cylinder 76 expand and contract, one of the horizontal shafts 7
3 and the other horizontal shaft 74 rotate in opposite directions, and the hooks 66 and 67 fixed to each horizontal shaft 73 and 74 engage and disengage from the recess of the hanging fitting 38.

The drive device 69 includes a drive cylinder 79 having a rotation shaft 78 operated by hydraulic pressure, a swing arm 80 pivoted to the upper end of the rotation shaft 78, and a crank pivoted to the rear of the truck 63. The other ends of the swing arm 8° and the crank arm 81 are rotatably connected to each other by a pin. Therefore, when the rotation shaft 78 is rotated counterclockwise or clockwise, the truck 63 moves back and forth via the swing arm 80 and the crank arm 81.

The first and second movable suction devices 11.14 have similar constructions, and as shown in FIGS. 1 and 6, the first and second movable suction devices 11. S5 and the first and second coagulator positions S3. A trolley 87 having wheels 85 that roll on the upper surface of rails 84 arranged in parallel along S6 and rollers 86 that are movable on the lower and side surfaces, and a positioning device for the mold 1 provided on the trolley 87. 88, a suction means 89 for suctioning air and gas in the mold 1 via the suction cover 4 placed on the mold l, and a suction means 89 for sucking air and gas in the mold 1, and a suction means 89 for moving the cart 87 to the first and second pouring positions 51S5 and the first and second coagulation holding machine position S
3. and a drive device 90 for driving the vehicle to and from S6. The rail 84 is mounted on the base 9■.

The positioning device 88 includes a pair of left and right positioning metal fittings 93 pivotally mounted on the truck 87, and the positioning metal fittings 93 are rotatable around a pivot shaft 95 by a fluid pressure cylinder 94. By the operation of the cylinder 94, the metal fitting 93 is rotated toward the mold, and its front surface is brought into contact with the side surface of the lower frame 45, thereby positioning the mold 1.

As shown in FIG. 8, the drive device 90 for the truck 87 is
A hydraulically actuated double rod cylinder 97 provided on the truck 87 and a pair of brackets 98 fixed to the base 9I.
The ends of both rods of the cylinder 97 are locked to the bracket 98 via end fittings 99. Therefore, as the rod expands and contracts, the carriage 87 travels back and forth on the rail 84 in the axial direction of the rod.

As shown in FIGS. 6, 9, and 10, the suction means 89 is detachably attached to the on-off valve 27 of the pair of suction holes 25 and 26 at the center of the suction cover 4 placed on the mold 1. a pair of suction cups 101, 102 that are fitted over the suction cups 101, 102; an elevating cylinder 103 for raising and lowering the suction cups 101, 102 relative to the on-off valve 27 between an attachment position and a detachment position;
A pair of conduits 104, 105 are provided for directing the gas in each suction cup 101, 102 to a separate suction source. Note that in the figure, the conduits are shown overlapping each other, so they appear to be one.

Each of the suction cups 101 and 102 has an elastic sealing material 106 attached to its lower end, and is slidably attached via a spring 107 to an elevating shaft 109 vertically disposed on an elevating plate 108. The elevating plate 108 is supported by a guide rod 106 and is raised and lowered by the elevating cylinder 103. A large-diameter portion 110 is formed at the lower end of the lifting shaft 109, and the upper portions of the suction cups 101, 102 are urged toward the large-diameter portion 110 by the spring 107. On the other hand, the suction cup 101.
102 is attached with an elevating tube 111 that communicates with the space inside the cup 101, 102, and the elevating tube 111 is slidably inserted into the suction box 112 via a gasket 117. A suction box 112 is secured in communication with the front end of each conduit 04.105. Both conduits 104 and 105 are fixed to a support 113 erected on the trolley 87, and an intake valve 114 whose pressure can be adjusted by adjusting the valve opening is provided at the rear end of each conduit 104, 105. In addition, it is connected to a suction source such as a separate blower, fan, or pump via a connecting pipe 115. Note that a remotely controllable intake valve or a dust collector may be appropriately provided in the middle of the suction source piping. Further, the lower ends of the suction cups 101 and 102 are open, and air is constantly sucked by the operation of the suction source. In the figure, arrows indicate the direction of suction of air and gas.

Said first and second fixed suction devices 9.10.12.13
have a similar configuration, and as shown in FIG. 1, they are respectively attached to the front outer surface of the rail attachment frame 60 of the suction cover transfer device via brackets 120, and a pair of suction cups 101, 102 and the mechanism for removably fitting it onto the on-off valve 27 of the suction cover 4 are similar to those of the mobile suction device. A base 121 of a suction device is attached to the bracket 120, and a pair of suction spaces 122 and 123 are defined in the base 121 and communicated with the pair of suction cups 101 and 102, respectively.
．． Although not shown, an intake valve is attached to 123, and is separately connected to the suction source by piping.

As shown in FIG. 6, the collection conveyor 8 has a roller 126 attached to the upper part of a link of a conveyance chain 125, and the chain 125 is driven by a motor via a speed reducer. In the middle of the conveyor frame 127, stoppers 128 and 129 are provided that protrude from the conveying surface (the upper surface of the roller) of the suction cover 4. A stopper 128 provided at the suction cover mounting position S1 is fixed to the motor storage frame 130, and a stopper 129 provided at the first pouring position 82 to the second suction cover collection position S7 is fixed to the conveying surface by a pneumatic cylinder or the like. However, they are said to be able to come and go as they please. 3 is a side guide, and conveyor frame 127
is fixed to the side of the

Next, the operation of the vacuum casting equipment according to the embodiment will be explained.

The equipment of the embodiment is equipped with two pouring devices, and there are cases in which only the first pouring device 2 is used, only the second pouring device 3 is used, and both of them 2.3 are used. be. First, the first basic case will be explained. in this case,
The devices used are a suction cover placement device 5, a first suction cover collection device 6, a collection conveyor 8, a first fixed suction device 9,
10, a first moving suction device 211, which are automatically operated by a sequence control device.

The suction cover mounting device 5 is waiting at the top of the mold conveyance line at the suction cover device position S1 with its truck 63 at the front end, the elevating frame 65 at the upper end, and the clamp device 68 holding the suction cover 4. At this time, when the mold 1 is conveyed to the suction cover mounting position SL by intermittent feeding,
The elevating frame 65 is lowered, the suction cover 4 is placed on the upper surface of the mold 1 (upper body type 43) at the lower end, and the hook 66.
After opening 67, raise it. When the elevating frame 65 reaches the upper end, intermittent feeding of the mold 1 becomes possible. Thereafter, the cart 63 of the suction cover placement device 5 is transferred to the collection conveyor 8.
After stopping at the rear end, the lifting frame 65 is lowered, and the hooks 66 and 67 of the clamp device F68 are engaged with the suction cover 4 on the collection conveyor 8 at the lower end, and then the lifting frame 65 is raised. The cart 63 is moved forward at the upper end and stands by while holding the suction cover 4 at the front end.

The mold I on which the suction cover 4 is placed is at the first pouring position S2.
It is conveyed by intermittent feeding. At this time, where is the suction cover placed? A new mold 1 is also transported to 1IS1, and the suction cover 4 is placed on the mold 1 as described above. When the mold 1 is transported to the first pouring level ff52, as explained in FIG. The lower edges of the cups 101, 102 are brought into contact with the upper surface of the mounting flange 40 of the main body 28 of the on-off valve 27 attached to the pair of suction holes 25, 26 on the feeding side. Further, the lifting shaft 109 is lowered against the spring 107, and the large diameter portion 110 of the lifting shaft 109 is lowered.
is brought into contact with the upper end of the valve stem 31 and pushed down. This results in
The spaces 22 and 23 inside the suction cover 4 are connected to two suction sources, and the mold l is connected through the gaps between the sand grains of the sand mold.
Exhaust the air inside.

In this state, when the molten metal is poured into the pouring port 51 from the first pouring device W2, the casting cavity 49 is quickly filled with the molten metal since it is in a reduced pressure state. Further, the gas generated by thermal decomposition of the casting sand on the surface layer of the casting cavity 49 is
The gas is exhausted to the outside from the suction cover 4 through the gaps between the sand grains of the lower body type 44, 47 and through the gas vent holes 53. At this time, by adjusting the capacity of the suction source of each system and the opening degree of the intake valve provided in the piping to the suction source, the peripheral space 22 of the suction cover 4 and the hollow part 52 and central space of the core mold 48 can be adjusted. 23 negative pressures are separately regulated.

Each space of the suction cover is divided and formed, so by connecting a separate suction source to each space, the gas generated from the casting sand and the air inside the casting cavity can be effectively removed regardless of the mold structure. can be discharged.

Note that the gas generated by the combustion of the binder in the sand mold contains explosive H2 and CO gas.

During suction, these gases fill each space of the suction cover. The high heat of the molten metal injected into the casting cavity ignites the gas in the gaps between the casting sand in the sand mold, and the flames propagate to each space, potentially causing an explosion inside the cover. By providing a safety valve on the suction cover, even if an explosion occurs, the high pressure inside the cover can be easily released to the outside, and damage to the cover and accidents caused by this can be prevented. Also, the gas flow velocity in the piping to the suction source is faster than the flame propagation velocity (preferably 30a/
It is preferable to draw in outside air through an intake valve or the like so as to reduce the gas concentration to below the explosion limit.

After the suction units 101 and 102 of the first fixed suction device 9 are attached to the on-off valve 27 of the suction cover 4, the mold 1 is positioned by the positioning device of the first movable suction device 11.
The suction cups 101 and 102 of the suction means 89 are similarly attached to the opening/closing valves 27 of the pair of suction holes 2526 in the center of the suction cover 4, and together with the first fixed suction device 9, the suction cups 101 and 102 of the suction cover 4 are connected to the respective spaces 22, 102 of the suction cover 4. The gas inside the mold 1 is sucked through 23. After pouring the hot water, the lifting cylinder 103 of the first fixed suction device 9 is operated to raise the suction cups 101 and 102 of the first fixed suction device 9 and remove them from the on-off valve 27. Thereby, the mold 1 becomes ready for transport. On this occasion,
The suction cups 101 and 102 of the first movable suction device 11 remain attached to the suction cover 4, and the suction state is maintained.

After the removal of the suction cups 101 and 102 of the first fixed suction device 9 is completed, the mold 1 is moved to the first pouring position S2 by intermittent feeding.
from there to the first coagulating and holding machine position S3.

All other molds are similarly moved one pinch at a time to the adjacent station. While the mold 1 moves from the first pouring position S2 to the first solidifying and holding machine position S3, the cart 87 of the first movable suction device fll also moves from the first pouring position S2 to the first solidifying and holding machine position S3. With respect to the mold 1 that has arrived at the first coagulating and holding machine position S3, the suction cups 101 and 102 of the second fixed suction device 10 on the delivery side are lowered, and the suction holes 25 and 26 of the suction cover 4 on the delivery side are opened. It is attached to the on-off valve 27 of.

After that, the first moving suction device 11 moves the suction cup 101,
102 is raised to return the cart 87 from the solidification standby position S3 to the first pouring position S2 at the upper end. The first movable suction device 11, which has returned to the first pouring level R52, similarly attaches the suction cups 101 and 102 to the mold 1 at the first pouring position S2, and repeats the same operation.

The mold 1 in the solidification standby position S3 is sucked by the second fixed suction device 210 for a predetermined period of time, and the molten metal in the casting cavity 49 solidifies while being sucked. After a predetermined time, the suction cup 101, 102 of the second stationary suction device 10 is pulled up,
The mold 1 becomes transportable.

Thereafter, the mold 1 at the first solidification holding position WS3 is transported to the first suction cover collection position S4 by intermittent feeding. At this time, the clamp device f68 of the first suction cover collection device 6 is waiting with the hooks 66 and 67 open above the transport line at the first suction cover collection position S4. The cart 63 of the device 6 is located at the front end, and the elevating frame 65 is located at the upper end. When the mold 1 arrives at the first suction cover collection position S4, the elevating frame 65 is lowered, and the clamp cylinders 75 and 76 are operated at the lower end to lock the hooks 66 and 67 to the hanging fittings 38 of the suction cover 4. Then, the elevating frame 65 is raised. When the top is reached, the mold l
becomes ready for transport. On the other hand, the cart 63 is moved backward at the upper end, the elevating frame 65 is lowered at the rear end, and the hook 66.
67 is opened and the suction cover 4 is unloaded onto the collection conveyor 8. Thereafter, the elevating frame 65 is raised with the hooks 66 and 67 open, the truck 63 is advanced at the upper end, and is locked at the front end position to wait.

First suction cover recovery position S with suction cover 4 removed
The mold 1 of No. 4 is intermittently conveyed from the second pouring position 35 to the second suction cover collection position S7, and further to the frame disassembly station, where it is disassembled, and the product is taken out.

On the other hand, the suction cover 4 unloaded onto the collection conveyor 8 is
As the stone bars 129 provided at the first suction cover collection position S4 to the first pouring position S2 move in and out, they are sequentially conveyed to the suction cover mounting position Sl.

When only the second pouring device 3 is used, the suction cover placement device 5, the second suction cover recovery device 7, the recovery conveyor 8,
A second fixed suction device 12, 13 and a second mobile suction device are used. Each common operation is the same as when only the first pouring device 2 is used.

In addition, when using the first and second pouring devices 2 and 3 at the same time, depending on the type of metal to be cast, the first and second pouring devices
The pouring devices 2 and 3 are used separately, the suction cover placement device 5 and the collection conveyor 8 are shared, and the first or second pouring device 2.
3, the first or second suction cover collection device 6, 7,
First or second fixed suction device 9.10.12.13, first
Or use the second moving suction device 11°14.

In the above embodiment, the suction cover 4 has a peripheral space 22
Although a structure in which the space is divided into a space 23 and a center space 23 is used, the structure is not limited to this, and a structure in which only a single space is formed may be used. In this case, there is one suction hole in each part.
It is sufficient to provide each one separately.

Further, as the suction device, two movable suction devices that move back and forth between the pouring device and the coagulation standby position may be provided, and each device may be used alternately to maintain the suction state from pouring to the completion of coagulation. In this case, a fixed suction device is not required.

Further, although two pouring devices are provided in the embodiment, it is of course possible to use only one pouring device, and in this case, there is no need for any other devices associated with the use of other pouring devices.

(Effects of the Invention) As explained above, according to the vacuum casting equipment of the present invention, a lower surface periphery having an opening on the lower surface and in close contact with the upper surface of the sand mold is formed, and a suction hole communicating with the opening is provided. Since the suction cover is provided, the air and gas inside the sand mold can be exhausted to the outside of the sand mold simply by placing the suction cover on the top surface of the sand mold. Therefore, when connecting the suction means, there is no risk of causing mold part warpage in the gas vent hole opened in the upper surface of the sand mold, and vacuum casting can be performed. In addition, by providing a suction cover placement device and a suction cover recovery device, the suction cover can be placed on the top surface of the sand mold without relying on human work.
In addition, it can be collected from the top surface of the sand mold, resulting in excellent productivity.
Vacuum casting can also be performed in mass production casting equipment. Furthermore, since a suction device that can freely suck the molten metal between the pouring position and the solidification standby position is provided, it is possible to continue suction after pouring the molten metal until the solidification is completed, and a high quality cast product can be obtained.

[Brief explanation of drawings]

Figure 1 is an overall plan view of the vacuum casting equipment according to the embodiment, Figure 2
The figure is a plan view of the suction cover and the mold, Figure 3 is a cross-sectional view taken along the line A-A in Figure 2, Figure 4 is a cross-sectional view taken along the line B-B in Figure 2, and Figure 5 is a cross-section of the main part of the suction cover. Figure 6 is A- of Figure 1.
An enlarged cross-sectional view taken along line A, FIG. 7 is a front view of the elevating frame of the suction cover transfer device, FIG. 8 is an explanatory diagram of the trolley drive device of the mobile suction device, and FIG. 9 is a cross-sectional side view of the main parts of the suction means of the mobile suction device. 10 are front views of the same suction means. 1...Mold, 2,3...Pouring device, 4...Suction cover 5...Suction cover mounting device, 6.7...Suction cover recovery device, 9.10.12.13 ...Fixed suction device, 11.14...Movable suction device, 25.26...
Suction hole, 101, 102... Suction cup. Figure 4 Figure 2 Figure 30 Figure 10

Claims (1)

[Claims] (1) The sand mold is transported intermittently at regular intervals, and at the pouring positions (S2) and (S5), the pouring devices (2) and (3)
In casting equipment in which molten metal is poured into the sand mold, suction holes (25), (26) have an opening on the lower surface, a peripheral edge of the lower surface is formed in close contact with the upper surface of the sand mold, and communicate with the opening.
A suction cover (4) is provided, and the suction cover (4) is placed on the upper surface of the sand mold at a suction cover placement position (S1) located on the feeding side in the conveying direction with respect to the pouring positions (S2) and (S5). A suction cover placement device (5) is provided for placing the sand mold, and the suction cover (4) is removed from the top surface of the solidified sand mold at the suction cover recovery positions (S4) and (S7) located on the sending side in the conveyance direction. Suction cover collection devices (6) and (7) are provided for the suction cover (4), and suction cups (101) and (102) are detachably attached to the suction holes (25) and (26) of the suction cover (4).
Suction devices (9) and (10) capable of freely sucking between the pouring positions (S2) and (S5) and solidification standby positions (S3) and (S6) set on the delivery side thereof; , (1
1), (12), (13), and (14) are provided.