JPS6048260B2 - Mold making method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold manufacturing method and apparatus suitable for molding both upper and lower molds at the same time.

Conventionally, the method of molding both the upper and lower molds at the same time is to align the upper and lower flasks with the upper and lower surfaces of a match plate that has a model part, and then use squeeze boards to open the upper and lower openings of these flasks, respectively. Generally, molding sand is supplied into the upper and lower flasks and then squeezed, but with this molding method, the molding sand is not supplied into the flask. Since this is carried out by blowing from the blowing port formed on the side, molding sand is blown into the area behind the bulging part of the model part when viewed from the blowing port. The filling of the molding sand is poor due to the inhibition of the molding sand, and the molding sand is hardened only by squeezing with a horizontal squeeze board, so in the case of a match plate with a complex shape, the entire mold must be made to have an even mold hardness. There is a drawback that sufficient mold hardness cannot be obtained, and this defect phenomenon is particularly likely to occur on the lower mold side. This invention was made in view of the above-mentioned problems, and involves supplying molding sand into a molding flask from above, and then compressed air is passed through the molding sand in the flask to transfer the molding sand to a molding board. The molding sand is solidified densely and strongly along the surface of the mold, and then squeezed to solidify it to a predetermined hardness, so that the entire mold can be evenly and sufficiently solidified even for complex-shaped model plates. The object of the present invention is to provide a mold making method and device that can finish the mold with high mold hardness.

An embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a rectangular parallelepiped-shaped base, and an upwardly facing cylinder 2 fixed to this base has its upper end connected to the base 1. It is located near the center of the top surface.

Reference numeral 3 denotes a rectangular lower squeeze board fixed to the upper end of the piston rod 2a of the cylinder 2, which forms a hollow chamber 4 inside and has a large number of small holes 5 penetrating into the hollow chamber 4 on the upper surface.
are drilled as appropriate.

Reference numerals 6 and 6 denote hollow guide bars that are slidably supported by guide holders 7 and 7 that are fixed to the base 1, and the upper ends of these are fixed to the lower surfaces of the lower squeeze boards 3 and 3. At the same time, the hollow chamber 4 is communicated with a compressed air source (not shown) through the inside of the guide bars 6, 6.

8. Seal backing 9 around the lower squeeze board 3
A frame-shaped lower presser that can be slid up and down via the frame. This member is raised and lowered by a cylinder (not shown) provided on the lower squeeze board 3.

Reference numeral 10 denotes four guide bars erected at the four corners of the base 1, on which arm members 12 protruding from the four corners of the lower flask 11 are slidably supported. A cylinder (not shown) separately supported by the base 1 allows the position directly above the lower squeeze hoard 3 to be raised and lowered.

The inner surface of the lower flask 11 is formed to expand downward, and the lower opening is set to a size into which the lower squeeze board 3 can be inserted. 13, 13 is a support member fixed to the guide bar 10 at a position above the arm member 12, and two guide bars 14, 14 extending back and forth are installed in parallel with this at an appropriate interval. , guide bar 14,
Both end portions of a frame-shaped carriage 15 are slidably fitted and supported by the frame-shaped carriage 14 .

Then, the carriage 15 is moved rearwardly by the expansion and contraction of a piston rod 16 of a shilling (not shown) supported by a frame (not shown) provided separately on the support member 13, and is moved in and out of the lower flask 11 directly above it. It's becoming like that. Reference numeral 17 denotes a match plate type model plate attached to the traveling base 15, which has a hollow chamber 18 formed inside thereof and has a large number of small holes 19, 19 bored through the hollow chamber 18 on each of the upper and lower sides. and an exhaust hole 20 communicating with the hollow chamber 18 on one side.
is formed.

Reference numeral 21 denotes an upper casting flask whose inner surface is formed into a lower wide shape and whose lower opening is set to approximately the same size as the upper opening of the lower casting flask 11, and arm members 22 protruding from the four corners of this flask serve as supporting members. 13
It is slidably supported by four guide bars 10 at a higher position.

The upper flask 21 is moved up and down by a cylinder (not shown) that is separately supported by guide bars 10, 10, and when it is lowered to the lowest position, the lower flask that has been raised to the uppermost position is moved up and down. The frame can be aligned with frame 11. A ceiling frame 23 is fixed to the upper end of the guide bar 10, and a rectangular upper squeeze board 25 is fixed to the lower end of the piston rod 24a of the downward sill 24 supported by the ceiling frame.

When the upper squeeze board 25 is lowered, the upper flask 21
The size is set so that it can be inserted into the upper opening of the holder, and a hollow chamber 26 is formed inside, and a number of small holes 27 penetrating into the hollow chamber 26 are appropriately bored in the lower surface. Reference numerals 28 and 28 denote hollow guide bars that are slidably supported by guide holders 29 and 29 that are fixed to the ceiling frame 23, and the lower ends of these bars are fixed to the upper surface of the upper squeeze board 25, and the hollow chamber is 26 is a guide bar 28,
It is connected to a compressed air source (not shown) through the inside of 28.

30 is provided around the upper squeeze board 25 via a seal backing 31 so that it can slide up and down! This is a frame-shaped upper pressing member, which is raised and lowered by a cylinder (not shown) provided on the upper squeeze board 25.

32 and 33 are the lower surface part of the lower flask 11 and the upper pressing member 30
This is a seal backing attached to the lower surface of the

34 is the base 1 and ceiling frame. A square cylindrical sand hopper 35 is provided on the upper part of the frame in parallel with the upper squeeze board 25.

Reference numeral 36 denotes an upper weighing hopper provided at the lower part of the sand hopper 35, which has a chute 36a on the left side wall shown in FIG. are integrally provided, and are supported so as to be able to reciprocate from side to side via rollers 37 that are pivotally supported by the frame 34.

The upper weighing hopper 36 has a storage capacity slightly larger than the molding sand storage capacity of the upper flask 21, and the size of its lower opening is set to be approximately equal to the size of the upper opening of the upper flask 21. Reference numeral 39 denotes a horizontally oriented cylinder rotatably supported by the frame 34 via a bracket 40, the tip of the piston rod 39a of which is connected to the lower surface of the gate member 38, and the piston rod 39a of this is extended and contracted. As a result, the upper weighing hopper 36 is moved from side to side to move in and out of a position directly above the upper flask 21.

Reference numeral 41 denotes an upper gate member for opening and closing the lower opening of the upper weighing hopper 36, and this is supported on a roller 42 pivotally supported by the frame 34 so as to be able to reciprocate from side to side.

43 is a bracket 4 fixed to the lower surface of the gate member 38
The piston rod 43a of this horizontal cylinder is pivotally supported by the upper gate member 41.

The frame 3 45 is located below the upper weighing hopper 36.
Auxiliary hopper fixed to 4, this is sand hopper 35
It has a rectangular cylindrical shape with the upper and lower openings having the same size as the lower opening of the upper weighing hopper 36, and a molding sand recovery port 4 is provided on the left side of the hopper.
6 and a chute 47 for this purpose.

The upper surface level of this auxiliary hopper 45 is the model plate 17.
The upper gate member 41 is set substantially equal to the upper surface level of the upper flask 21 placed thereon, and the upper gate member 41 is adapted to move left and right along the upper surface of the auxiliary hopper 45 . 78 and 4
Reference numeral 9 denotes a lower weighing hopper and a lower gate member provided at the lower part of the auxiliary hopper 45. These have substantially the same configuration as the upper weighing hopper 36 and the upper gate member 41, and the lower weighing hopper 48 is attached to the frame 34 with a shaft. The lower gate member 4 is supported so as to be able to reciprocate from side to side via supported rollers 50.
9 is supported via a guide plate 51 and rollers 52 supported by the frame 34 so as to be able to reciprocate from side to side.

Further, 48a is a chute provided on the left side wall of the lower weighing hopper 48, and 53 is an auxiliary hopper 4 provided on the right side wall of the lower weighing hopper 48.
This is a gate member that is integrally provided to open and close the lower opening of No. 5. Reference numeral 54 designates a horizontal cylinder that drives the lower weighing hopper 48, which is rotatably supported by a bracket 55 fixed to the frame 34, and which connects the tip of its piston rod 54a to the gate member 53. .

Reference numeral 56 denotes a horizontal cylinder that drives the lower gate member 49. This cylinder is rotatably supported by a bracket 57 fixed to the lower surface of the gate member 53, and the tip of a piston rod 56a is connected to the lower gate member 49. has been done.

Reference numeral 58 denotes a horizontal mold extrusion sill attached to the base 1 via a bracket 59, and the piston rod 5 of this
An extrusion plate 60 is fixed to the tip of 8a.

In addition, 61 is the spanning plate of the mold, 62 and 63 are the chutes, and 6
4 has a sand collection box. Next, the operation of this embodiment configured as above will be explained.

First, the state is such that each part is in its original position as shown in FIG. The process of simultaneously molding the upper and lower molds will be explained below in order. first,
The cylinders 39 and 54 are extended, respectively, and the upper and lower weighing hoppers 36 and 48 are moved to the upper and lower gate members 41 and 4.
9 are moved to directly above the upper and lower casting flasks 21 and 11, and subsequently the shillings 43 and 56 are contracted to move the upper and lower gate members 41 and 49 to the right, and each weighing hopper 36 , 48 are opened, and the molding sand in each weighing hopper 36, 48 is charged into the upper and lower flasks 21, 11 from above (see FIG. 2). At this time, top
As the lower weighing hoppers 36, 48 move to the right, the gate members 38, 53 are also moved to the right, and the lower openings of the sand hopper 35 and the auxiliary hopper 45 are closed, respectively. Next, the cylinder 54 is contracted and the cylinder 56 is extended simultaneously, and the lower weighing hopper 48 and the lower gate member 49 are returned to their original positions as shown in FIG. Then, at the same time as the cylinder 54 is retracted, the cylinder 39 is also retracted,
The upper weighing hopper 36 is returned to its original position with its lower opening open. At this time, the molding sand on the upper and lower flasks 21, 11 is scraped up by the lower ends of each weighing hopper 36, 48 and collected into the auxiliary hopper 45 and sand collection box 64 via the chutes 47, 62. (See Figure 3). Additionally, as the lower weighing hopper 48 returns to its original position, the auxiliary hopper 45
The foundry sand in the sand hopper 35 is filled into the lower weighing hopper 48, and as the upper weighing hopper 36 returns to its original position with its lower opening open, the foundry sand in the sand hopper 35 passes through the upper weighing hopper 36 and is assisted. The hopper 45 is filled, and the upper weighing hopper 36 is also filled. After the upper weighing hopper 36 is returned to its original position, the cylinder 43 is extended after a predetermined period of time has elapsed, and the upper gate member 41 is returned to its original position as shown in FIG.
Now, when the contraction operation of the cylinders 39 and 54 described above is completed, the cylinder 2 is extended and the lower squeeze board 3 is raised and placed on the lower presser member 8 whose upper surface level is the same as that of the lower squeeze board 3. The lower flask 11 is the model plate 1.
7 and closes the upper opening of the lower flask 11, and at the same time, the cylinder 24 is extended and the upper squeeze board 25 is lowered to make the lower surface level the same as that of the upper squeeze board 25. The upper pressing member 30 is brought into contact with the upper surface of the upper flask 21 via the seal backing 33, and the upper flask 2
The upper opening of No. 1 is closed (see Figure 3).

Next, when compressed air is supplied into the hollow chambers 4 and 26 through the guide bars 6 and 28, this air is injected from the small holes 5 and 27 into the lower and upper flasks 11 and 21, and the lower and upper flasks. Passing between the particles of molding sand filled in the frames 11 and 21,
The compressed air is exhausted to the outside from the exhaust hole 20 through the small holes 19, 19 and the hollow chamber 18 of the model plate 17, and the molding sand particles are blown onto the upper and lower surfaces of the model plate 17, and the molding sand is The molding sand is finely and firmly solidified along the surface of the plate 17. Subsequently, the cylinders 2 and 24 are further extended, and at the same time a cylinder (not shown) is operated, the lower presser member 8 is lowered relative to the lower squeeze board 3, and the upper presser member 30 is lowered relative to the upper squeeze board 25. Then, the lower and upper squeeze boards 3 and 25 are inserted into the lower and upper flasks 11 and 21, and the molding sand that has passed through the compressed air is simultaneously squeezed from both the upper and lower sides to the desired extent. (See Figure 4). After completing the squeeze,
The cylinder 24 is compressed and the upper squeeze board 25 is raised, and subsequently the upper flask 21 is raised by the operation of a cylinder (not shown), and the upper flask 65 is removed. Further, at the same time as the cylinder 24 is retracted, the cylinder 2 is retracted and the lower squeeze board 3 is lowered, and subsequently the lower flask 11 is lowered by the operation of a cylinder (not shown), and the lower flask 66 is removed from the mold. (See Figure 5). Next, by contracting the cylinder (not shown), the model plate 17 is pulled out from between the upper and lower flasks 21 and 11 via the piston rod 16, and then the lower flask 11 is opened again. After being raised to the uppermost position and lowering the upper flask 21 to perform frame alignment, the lower squeeze board 5 is inserted again into the lower flask 11 by the extension action of the cylinder 2, and the lower mold 66 is supported. At the same time as the cylinder 2 is extended, the cylinder 24 is also extended, and the upper squeeze board 25 is inserted into the upper flask 21 again, and the upper mold 65 is supported. Lower molds 65 and 66 are held in between. Subsequently, the upper and lower squeeze boards 25 and 5 are lowered by a predetermined distance in synchronization, so that the upper and lower molds 65 and 66 are punched out from the upper and lower flasks 21 and 11, respectively. The lower squeeze board 5 on which the cut upper and lower molds 65 and 66 are placed is then lowered to the lowest position, and the upper and lower molds 65 and 66 are placed on the lower squeeze board 5.
The lower molds 65, 66 are pulled out below the upper and lower flasks 21, 11 (see FIG. 6). Note that the lower presser member 8 is returned to its original position while the lower squeeze board 5 is being lowered. Subsequently, the cylinder 58 is extended, and the frameless upper and lower molds 65 and 66 on the lower squeeze board 5 are pushed out to the left in FIG. It is sent out onto a conveyor that does not work. Upper and lower molds 65, 6
6, the cylinder 58 is retracted to return to its original position, and subsequently the lower flask 11, upper squeeze board 25, and upper presser member 30 are each returned to their original positions as shown in FIG. Then, the upper flask 21 is once raised to the uppermost position, and at this time the model plate 17 is moved back to just above the lower flask 11, and then the upper flask 21 is lowered and returned to the original position shown in FIG. It will be done. By repeating the above operations, a mold consisting of upper and lower molds 65 and 66 without a frame is continuously and intermittently molded.

In the above embodiment, the upper opening of the upper flask 21 and the lower opening of the lower flask 11 are hermetically closed by the upper and lower squeeze boards 25, 3 and the upper and lower press members 30, 8. , to prevent leakage of the compressed air injected from the small holes 27, 5, sealing members are attached to all outer surfaces of the upper and lower squeeze boards 25, 3. 3 may be slightly inserted into the upper and lower casting flasks 21, 11 and closed in an airtight manner. In this case, the upper and lower holding members 30, 8 can be omitted.

As is clear from the above description, in the present invention, molding sand is introduced from above into a molding flask whose lower opening is closed by a lower squeeze hoard, and then a model plate is joined to the upper surface of the flask and sand is injected from the lower squeeze board. By passing the compressed air through the molding sand in the molding flask and exhausting it through the small holes of the model plate, the molding sand is blown to every corner of the model plate and is densely and firmly coated on the surface of the model plate. After that, the molding sand is further squeezed using a model plate and a lower squeeze rod to solidify the molding sand to a predetermined hardness, after which the mold is separated from the mold plate and the mold is cut out. Because of this, even if the shape of the model is complex, the casting sand is filled uniformly over the entire flask, and the entire mold is uniformly finished to a sufficient mold hardness. Therefore, even if the shape of the model is complex, there will be no problems like the conventional structure where the mold is partially insufficient in mold hardness and sufficient mold hardness cannot be obtained.
Moreover, since this method for molding the mold is applied to the molding of the lower mold, and then the upper mold is molded using the same method, the two can be combined, so the upper and lower molds can be manufactured simultaneously and easily. The effect this model has on the industry is enormous.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional view of the whole, and FIGS. 2 to 6 are explanatory diagrams of the operation. In the drawing, 3 is a lower squeeze board, 4 is a hollow chamber, 5 is a small hole, 11 is a lower flask, 17 is a model plate, 18 is a hollow chamber, 19 is a small hole, 20 is an exhaust hole, and 25 is an upper squeeze board , 26 is a hollow chamber, 27 is a small hole, 35 is a sand hopper, 36 is an upper weighing hopper, 41 is an upper gate member, 45 is an auxiliary hopper,
48 is a lower weighing hopper, 49 is a lower gate member, 60 is an extrusion plate, 65 is an upper mold, and 66 is a lower mold.

Claims (1)

[Claims] 1. A step of charging molding sand from above into a flask whose lower opening is closed with a lower squeeze board, and joining a model plate with a large number of small holes to the upper surface of the flask. a step of injecting compressed air from a lower squeeze board to pass through the molding sand in the flask and discharge it from the small hole of the model board;
A mold making method comprising the steps of squeezing molding sand through which compressed air has passed using the model plate and a lower squeeze board, and separating the model plate and flask to perform mold cutting. 2. The process of pouring molding sand from above into the upper flask, which is fitted onto a match plate-type model board with a large number of small holes that communicate with the outside air, and the lower opening is closed, and the lower opening is closed with a lower squeeze board. The step of charging molding sand from above into the lower flask closed by A step of closing the upper opening of the upper flask, and blowing compressed air from the upper squeeze board and the lower squeeze board to pass through the molding sand in the upper flask and the lower flask to open small holes in the model plate. a step of squeezing the molding sand through which the compressed air has passed in the upper and lower flasks using the upper and lower squeeze boards and the model plate; and a step of separating the model plate from the superimposed relationship and cutting the mold. 3. A lower squeeze board device that has a hollow chamber that can communicate with a compressed air source inside and has a number of small holes that communicate with the hollow chamber on its upper surface and is arranged to be movable up and down, and this lower squeeze board. A lower flask device is arranged directly above the device so that it can be raised and lowered, and a lower flask device is placed directly above the lower squeeze board device and placed in the lowered position so that it can be moved in and out. A match plate type including a weighing hopper device, and a match plate type which is disposed so as to be accessible and removable directly above the lower flask device at a position above the lower weighing hopper device, and has a number of small holes communicating with outside air on each of the upper and lower sides. a model plate, an upper flask device disposed above the model plate so as to be movable up and down in correspondence with the lower flask device, and an upper flask device placed on the model plate at a position directly above the lower flask device. There is an upper weighing hopper device which is removably disposed directly above the upper flask device located at A mold making device comprising: an upper squeeze board device having a small hole drilled therein and movably disposed directly above the upper flask, and positioned above the upper weighing hopper device when placed in the raised position.