JPH10216902A - Method for supplying compressed air for blowing in blow squeeze type molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely fill up molding sand into a flask body while fluidizing the molding sand in a blow head by making the pressure in the blow head lower than the pressure in a sand magazine in the specific range, at the time of blowing the molding sand in the upper and the lower blow heads into the upper and the lower flask bodies. SOLUTION: At the time of blowing and filling up the molding sand in the upper and the lower blow heads 4, 5 into the upper and the lower flask bodies 2, 3, the pressure in the upper and the lower blow heads 4, 5 is made to lower by the range of <=0.1MPa differential pressure than the pressure in the sand magazine 6. The pressure in the sand magazine 6 is made to the max. of about 0.18MPa accompanied with the pressure loss, and the pressure in the upper and the lower blow heads 4, 5 is made to about 0.15MPa by adjusting with an upper and a lower, first and second compressed air injecting mechanisms 12-15. Even if the molding sand in the upper and the lower blow heads 4, 5 is pressed with the compressed air supplied into the sand magazine 6, the molding sand is blown into the upper and the lower flask bodies 2, 3 under fluidized condition with the compressed air injected from a vent plug.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blow squeeze type
The present invention relates to a method for supplying compressed air used to blow air into a lower frame.

[0002]

2. Description of the Related Art As one of blow squeeze type mold making machines, as disclosed in Japanese Utility Model Publication No. 2-14833,
The match plate, the upper and lower frames arranged so as to be able to abut against the upper and lower surfaces of the match plate, and the upper and lower frames arranged so as to be movable up and down and abutted on the match plate There is an upper / lower blow head capable of blow squeezing molding sand, and a sand magazine capable of blowing and supplying molding sand to the upper and lower blow heads.

[0003]

However, in the mold molding machine constructed as described above, the molding sand is supplied from one sand magazine to the upper and lower blow heads, respectively. It is designed to simultaneously blow molding sand into the upper and lower frames. Therefore, it is very difficult to properly fill the upper and lower frames with the molding sand.
As disclosed in Japanese Unexamined Patent Publication No. 337605, there has been proposed a structure in which the upper and lower blow heads are each provided with a compressed air ejection mechanism for ejecting compressed air for changing the forward direction of the molding sand in the upper and lower blow heads. However, there is still a problem that the molding sand cannot be filled into the upper and lower frames properly. The present invention has been made in view of the above circumstances, and an object thereof is to provide a blow squeeze type having a mechanism capable of accurately and sufficiently filling molding sand into each of the upper and lower frames. In the mold making machine, the casting sand in the upper and lower blow heads is
An object of the present invention is to provide a method of supplying compressed air used for blowing into a lower frame.

[0004]

In order to achieve the above object, a method for supplying compressed air for blowing in a blow squeeze type molding machine according to the present invention comprises a match plate and upper and lower surfaces of the match plate. An upper / lower frame that is provided so as to be abuttable, and an upper / lower blow head that is provided so as to be able to move up and down and that can blow-squeeze molding sand against the upper and lower frames that are in contact with the match plate. A sand magazine capable of blowing and supplying casting sand to the upper and lower blow heads, and an upper and lower blow head provided on the upper and lower blow heads, respectively.
An upper / lower first compressed air ejection mechanism for ejecting compressed air for changing a forward direction of molding sand in the lower blow head;
An upper and lower second compressed air ejection mechanism that is attached to a side portion and a lower portion of a substantially horizontal portion of the lower blow head and ejects compressed air for fluidizing the molding sand; A method for supplying compressed air in a blow-squeeze type mold molding machine wherein blow molding sand is simultaneously blow-squeezed to a lower frame body, wherein the molding sand in the upper and lower blow heads is blown into the upper and lower frame bodies. In the above-mentioned method, the pressure in the upper and lower blow heads is made lower than the pressure in the sand magazine within a range of a differential pressure of 0.1 MPa or less.

[0005]

According to the method for supplying compressed air for blowing of the present invention, when the molding sand in the upper and lower blow heads is blown and filled into the upper and lower frames, the differential pressure is within a range of 0.1 MPa or less. Since the respective pressures in the upper and lower blow heads are lower than the pressure in the sand magazine, the molding sand in the upper and lower blow heads is pressed by the compressed air supplied to the sand magazine, The fluid is dissociated by the compressed air ejected from the upper and lower first and second compressed air ejection mechanisms, respectively, and fluidization is promoted. As a result,
The molding sand in the sand magazine is moved into the upper and lower blow heads while maintaining the fluidized state, and the molding sand in the upper and lower blow heads is also compressed by the upper and lower second compressed air injection mechanisms. While maintaining the fluidized state by the air, the compressed air ejected from the upper / lower first / second compressed air ejection mechanism is blown into the upper / lower frame body. When the pressure difference exceeds 0.1 MPa, the molding sand in the upper and lower blow heads is pressed and solidified by the compressed air supplied to the sand magazine in proportion to the magnitude of the pressure difference. Therefore, the filling state of the upper and lower frames is deteriorated.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIG. The blow squeeze type molding machine used to carry out the present invention is a match plate 1
And upper and lower frames 2 and 3 arranged to be able to contact the upper and lower surfaces of the match plate 1 respectively, and upper and lower frames arranged to be able to move up and down and to be in contact with the match plate 1 An elbow-shaped upper and lower blow heads 4 and 5 capable of blow-squeezing molding sand to the bodies 2 and 3; a sand magazine 6 capable of blowing and supplying molding sand to the upper and lower blow heads 4 and 5; Upper and lower frames 7 and 8 are provided between the upper and lower frames 2 and 3 and the upper and lower blow heads 4 and 5 so as to be able to move up and down, respectively.

The upper and lower frames 2, 3 are lifted and lowered by a cylinder (not shown). The upper and lower blow heads 4 and 5 are mounted on tips of piston rods of cylinders 10 and 11 mounted on a frame 9 separately provided, and move up and down by the expansion and contraction operations of the cylinders 10 and 11, respectively. It has become. The upper and lower blow heads 4 and 5 blow out compressed air for changing the forward direction of the molding sand in the upper and lower blow heads 4 and 5.
Lower first compressed air jetting mechanisms 12 and 13 and upper and lower second compressed air jetting mechanisms for jetting compressed air for fluidizing molding sand on the side and lower portions of the substantially horizontal portions of upper and lower blow heads 4 and 5. 14, 15 and upper and lower blow heads 4, 5
Upper and lower guide members 4a and 5a are provided, respectively, for guiding the foundry sand inside the upper and lower blow heads 4 and 5 once to converge to the central portion thereof and then dispersing the foundry sand toward the entire tip opening.

The upper and lower first compressed air ejection mechanisms 12, 1
2 and the upper / lower second compressed air ejection mechanisms 14 and 15 are respectively bent as shown in FIG. 2 (only the lower first and second compressed air ejection mechanisms 13 and 15 are shown). First and second hollow chambers 1 respectively formed in the horizontal and horizontal sections
6, 17; and a plurality of vent plugs 20, 21 fitted in a plurality of first and second through holes 18, 19, which are respectively provided through the wall surfaces of the first and second hollow chambers 16, 17. , The first
It is composed of a compressed air source (not shown) connected to the second hollow chambers 16 and 17.

[0009] As shown in FIG.
In the above, cylindrical upper and lower sand storage tanks 22 and 23 having compressed air supply ports 22a and 23a connected to a compressed air source (not shown) are separately provided and fixed. At the lower ends of the lower sand storage tanks 22 and 23, upper and lower bent cylinders 24 and 25, which can communicate with the base openings of the upper and lower blow heads 4 and 5, respectively, are mounted. Upper and lower cylinders 26, which are provided with slits in the lower sand storage tanks 22, 23,
27 are provided inside, and a first slide gate mechanism 28 is mounted on the upper end of the upper sand storage tank 22. Also,
The upper / lower blow heads 4, 5 and the upper / lower bent cylinder 2
Upper and lower second slide gate mechanism 2 between
9 and 30 are respectively mounted. The upper and lower bent cylinders 24 and 25 are provided with upper and lower compressed air supply mechanisms 31 and 32 for supplying compressed air toward the distal end openings, respectively. In addition, the upper and lower embossing frames 7 and 8 are respectively mounted on the distal ends of the piston rods of the upper and lower second cylinders 33 and 34 mounted on the frame 9.

[0010] In the above-mentioned structure, a predetermined amount of molding sand is charged into the upper and lower sand storage tanks 22 and 23 under the state shown in the figure, and then compressed air is supplied to the sand magazine 6. The upper and lower blow heads 4 and 5 are brought closer to each other by the extension operation of the cylinders 10 and 11,
5 is blow-squeezed to the upper and lower frames 2 and 3 and the upper and lower filling frames 7 and 8, respectively, and at the same time, the upper and lower first compressed air ejection mechanisms 12 and 13 and the upper and lower Vent plugs 20, 20, 2 of the second compressed air ejection mechanisms 14, 15
Compressed air is ejected from 1, 21 respectively. Then
First, the molding sand that has flowed into the upper and lower blow heads 4 and 5 from the upper and lower sand storage tanks 22 and 23, respectively, is entirely fluidized by compressed air injected from the vent plugs 20, 20, 21 and 21. After being converged to the central portion by the guide members 4a, 5a, it is dispersed over the entire opening of the tip of the upper / lower blow heads 4, 5, and then the tip of the upper / lower blow heads 4, 5 The upper and lower frames 2 and 3 and the upper and lower embossing frames 7 and 8 are blown into the spaces defined by the openings, and are squeezed at the same time.

In this case, when the molding sand in the upper and lower blow heads 4 and 5 is blown into the upper and lower frames 2 and 3 to fill the upper and lower blow heads with a differential pressure of 0.1 MPa or less. Each pressure in 4 and 5 is made lower than the pressure in sand magazine 6. That is, for example,
Compressed air supply ports 22a, 23a of lower sand storage tanks 22, 23
Compressed air at a pressure of 0.30 MPa is supplied to the upper / lower first / second compressed air ejection mechanisms 12 to 15 for about 1.5 seconds. Then, as shown in FIG. 3, the pressure in the sand magazine 6 is about 0.18MP at maximum due to the pressure loss.
a. Further, the respective pressures in the upper and lower blow heads 4 and 5 correspond to the upper and lower first and second compressed air ejection mechanisms 12 to
In step 15, the flow rate of the compressed air is adjusted appropriately to about 0.15 MPa. Accordingly, the molding sand in the upper and lower blow heads 4 and 5 is pressed by the compressed air supplied to the sand magazine 6 even if the vent plugs 20 and 2 are pressed.
Dissolved by compressed air ejected from 0, 21, and 21, fluidization is promoted. As a result, Sand Magazine 6
The molding sand in the upper and lower blow heads 4 and 5 is moved while maintaining the fluidized state, and the molding sand in the upper and lower blow heads 4 and 5 is also vented while maintaining the fluidized state. The compressed air ejected from 20, 20, 21, 21 is blown into the upper and lower frames 2, 3, respectively. Thus, after the completion of the blow squeeze of the molding sand, the normal operation of this type of mold molding machine is performed, whereby the frameless upper and lower molds can be molded.

[0012]

As is apparent from the above description, the present invention provides a method for blowing and filling the molding sand in the upper and lower blow heads into the upper and lower frames within a pressure difference of 0.1 MPa or less.・ Because each pressure in the lower blow head is made lower than the pressure in the sand magazine, the upper and lower molding heads are fluidized as a whole.
Since the casting sand can be blown into the lower frame,
An excellent effect such as being able to accurately and sufficiently fill each of the lower frames is achieved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a mold making machine for carrying out the present invention.

FIG. 2 is an enlarged detail view of a portion A in FIG. 1;

3 is a graph showing pressure changes in a sand magazine and upper and lower blow heads when compressed air for blowing is supplied to the mold making machine shown in FIG. 1.

[Explanation of symbols]

 2, 3 Upper / lower frame body 4, 5 Upper / lower blow head 6 Sand magazine 12 Upper first compressed air ejection mechanism 13 Lower first compressed air ejection mechanism 14 Upper second compressed air ejection mechanism 15 Lower second compressed air ejection mechanism

Claims (1)

[Claims] 1. A match plate 1; upper and lower frames 2 and 3 provided so as to be able to abut against upper and lower surfaces of the match plate 1, respectively; Upper and lower blow heads 4 and 5 that can blow squeeze molding sand to the upper and lower frame bodies 2 and 3 that are in contact with each other, and sand that can blow and supply molding sand to the upper and lower blow heads 4 and 5. A magazine 6 and the upper and lower blow heads 4,
5, upper and lower first compressed air ejection mechanisms 12, 13 for ejecting compressed air for changing the advancing direction of the molding sand in the upper and lower blow heads 4, 5, respectively; 5, upper and lower second compressed air ejecting mechanisms 14 and 15 for ejecting compressed air for fluidizing molding sand, which are mounted on substantially horizontal portions of the upper and lower parts, which are in contact with the match plate 1. A method for supplying compressed air for blowing in a blow squeeze type mold molding machine in which molding sand is blow-squeezed simultaneously with respect to frames 2 and 3, wherein the molding sand in the upper and lower blow heads 4 and 5 is removed. The upper and lower frames 2, 3
When blowing and filling the inside, each pressure in the upper and lower blow heads 4 and 5 is set to be lower than the pressure in the sand magazine 6 within a range of a differential pressure of 0.1 MPa or less. Of supplying compressed air for blowing in a blow squeeze type mold making machine.