JPH0645154B2 - Reactive low pressure mixing casting equipment - Google Patents

Description

Detailed Description of the Invention

The present invention relates to a mixing casting apparatus suitable for a reaction type low pressure casting.

[0002]

2. Description of the Related Art The reactive injection molding method (RIM) is used for molding automobile bumpers and the like.
It is not suitable for high-mix low-volume production due to high-speed mixing.
The low-pressure casting method (LPCM) is a method of casting a low-viscosity raw material liquid of several cp to several thousand cp at 1 to 5 atmospheric pressure, and is suitable for small-scale production, but the casting in the mixer is performed for each casting. Cleaning is indispensable. For this reason, a device such as Jikkei 1-8336 has been proposed as a low pressure casting raw material mixing device equipped with a cleaning means. This device has a raw material supply valve on the primary side of the mixer chamber for switching between the supply raw material and the cleaning liquid, has two inflow ports and three outflow ports on its secondary side, and is equipped with a switching valve connected to the mold and the cleaning liquid tank. Is configured. However, even with this device, it takes a long time to clean the inside of the mixer,
It was not sufficient to obtain a high-purity resin molded product.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides an apparatus capable of cleaning a casting liquid passage downstream from a primary side of a mixer in a short time and in a substantially complete manner. It is intended to provide an apparatus capable of economically manufacturing a cast product.

[0004]

An apparatus of the present invention includes a cleaning liquid tank and a recovery liquid tank in addition to a raw material tank, and a raw material-cleaning liquid switching valve (raw material valve),
Compact high-performance static line mixer for casting (mixing mold) that supplies the casting liquid to the mold, casting liquid-cleaning liquid switching valve (casting valve), and cleaning liquid of the same configuration as the mixer-
A recovery liquid mixing mixer (recovery mixer) and a recovery liquid-cleaning drainage switching valve (recovery valve) are provided, and 1 is achieved by sequentially switching each valve.
For each casting, the inside of the pipe is cleaned by the cleaning liquid, the raw material liquid and the cleaning liquid are recirculated by the circulation line, and the cleaning waste liquid is collected in the recovery tank together with the recovery liquid to form a closed system, and the materials used outside. It is configured so as not to be released.

That is, a plurality of raw material valves which respectively form a circulation path and are connected to a plurality of raw material tanks and a cleaning liquid tank, a raw material mixing casting mixer connected to the secondary side of the raw material valves, and an exhaust of the mixer. A casting valve which is connected to the outlet and constitutes a circulation path with the cleaning liquid tank, a mold connected to the valve, and the casting valve
A casting line recovery mixer having a secondary line connected to one of the inlets and a recovery liquid tank forming a circulation path and connected to the cleaning liquid tank and the other inlet of the recovery mixer. In the casting liquid passage pipe including the casting mixer by switching the valves for each casting, and the discharge port of the collection mixer is connected to the collection valve. It is configured such that the casting liquid remaining in (1) is washed with the washing liquid, and the washing liquid containing the casting liquid is mixed with the collecting liquid and collected in the collecting liquid tank.

As shown in FIGS. 2 and 3, each switching valve in the present invention is a two-passage simultaneous switching type five-way valve, which has two inflow ports and three outflow ports, respectively, and is provided in the valve body 50. The flow passages F1, F2 and G1, G2 are formed by switching the rotating body 51 of FIG. The line mixer is as shown in FIG. 4, and the mixing block 6 has a cylindrical case 60 in which a large number of intersecting portions 64 formed by the cross-shaped grooves 62 and 63 are formed on the surface of the cylindrical body 61.
5 is housed in an external pressurizing elastic tube 66, the raw materials A and B to be mixed are supplied from an introducing passage 67 provided at one end of the block through a distribution cone 68, and the mixed liquid is a collecting cone at the other end. It is discharged from the discharge port 70 via 69, and its details are described in Japanese Patent Application No. 3-33424.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings, raw material liquids A and B, cleaning liquid C and recovery liquid D are respectively pressure feed pumps 2a, 2b, 11 and 31 and weighing pumps 3a, 3b, 12a and 12 paired with them.
b, 12c, 31 connected in series to the quantitative supply device PA,
Liquid is delivered by PB, P11, and P31. Pressure regulating valves 4a, 4b, 5a, 5b, 13a, 13b, 13c, 1
Nos. 4, 33, and 34 are publicly known ones, and all of them are for absorbing the pressure fluctuation in the pipe during valve switching or during liquid feeding, and therefore description thereof will be omitted.

Reference numerals 1A and 1B are raw material supply lines, which are connected to the first inflow port of the raw material valve V1, respectively. Although the raw material valve V1 may be provided separately for the number of raw materials, a double 5-way valve is used in the figure. Reflux line 8A, 8B
Is connected to the first outflow port of V1, the cleaning liquid supply lines 10A and 10B are connected to the second inflow port,
The cleaning liquid recirculation lines 17A and 17B are connected to the second outflow port.

Each inlet of the casting mixer M1 has a line 16
Each raw material is supplied by being connected to the third outflow port of the valve V1 via A and 16B, and the mixed casting liquid line 18 is connected to the first inflow port of the casting valve V2. Line 16
A, 16B and 18 are extremely short distances. 20 is a casting line and 21 is a mold. The second inflow port of the valve V2 is connected to the cleaning liquid supply line 10C, and the second outflow port is connected to the line 22 returning to the cleaning tank CT. The third outflow port is connected via a line 23 to one inflow port of the recovery mixer M2.

The discharge line 25 of the mixer M2 has a recovery valve V3.
The line 27 that is connected to the first inflow port and the second outflow port is connected to the other inflow port of the recovery mixer M2. The first outlet port of the valve V3 is connected to the cleaning tank CT by the line 28. The recovery liquid supply line 29 is connected to the second inflow port of V3, and the third outflow port is connected to the recovery liquid tank DT by the reflux line 30.

[0011]

[Table 1] Flow path of each valve Process V1 V2 V3 (1) Pipe cleaning process G F G (2) Raw material supply starting process F F G (3) Casting liquid replacement process F F F (4) Casting starting process F G F (5) Recovery line cleaning liquid recirculation process F G G (6) Raw material supply stopping process G G G (7) Cleaning liquid recovery process G F F

[0012]

In the above device, the switching valves V1, V2 and V3 are set in Table 1 while all of the various quantitative supply devices are driven.
And the timing is determined by the physical properties such as the viscosity of the liquid and the casting conditions.

(1) In-pipe purification step V1 is in the G state of FIG. 3, V2 is in the F state of FIG. 2, and V3 is in the G state, and the raw material liquids A and B are from the pipelines 1A, 1B to 8 respectively.
Reflux through A, 8B and lines 10A, 10B
The cleaning liquid C supplied from the cleaning liquid C returns to the cleaning liquid tank through the casting mixers M1 and V2, the recovery mixer M2 and the recovery valve V3, and cleans the inside of the pipeline between them. (2) Raw Material Liquid Supply Starting Step Only the raw material valve V1 is switched to the F state of FIG.
B is supplied to the casting mixer M1, and at the same time, the flow path of the cleaning liquid C is also switched so as to flow back from V1 to the cleaning tank C through the lines 17A and 17B. Cast mixer M1, lines 18, 2
3. The residual cleaning liquid in the recovery mixer M2 flows into the cleaning liquid tank CT so as to be pushed out by the supplied raw material liquid.

(3) Casting liquid replacement step In the mixer M1, the raw material liquids A and B are mixed, and when the mixed casting liquid reaches the recovery mixer M2 through the line 23 (in the M1 and the line 18). The cleaning liquid therein is almost completely replaced with the casting liquid) The recovery valve V3 is switched to the F state. As a result, the recovered liquid D, which has been refluxed to the recovered liquid tank through the lines 29 and 30 until then, is recovered by the recovery mixer M.
2 is supplied to one of the inlets, is mixed with the casting liquid from the line 23, and is received in the recovery liquid tank through the lines 25 and 30. (4) Casting start step Immediately after this, the casting valve V2 is switched to the G state, and the mold 21
The casting liquid is supplied to. At the same time, the cleaning liquid C supplied from the line 10C enters the recovery mixer M2 from the line 23, is mixed with the recovery liquid D, and pushes out a small amount of the raw material component remaining in the mixer M2 and sends it to the recovery liquid tank.

(5) Recovery line cleaning liquid reflux The recovery valve V3 is switched to the G state to stop the supply of the recovery liquid to the mixer M2, the recovery liquid D circulates through the lines 29 and 30, and only the cleaning liquid C is mixed in the mixer M2. , Line 25
And is returned to the cleaning liquid tank CT through the line 28. (6) Raw Material Supply Stopping Process Since the switching valve V1 is switched to the initial G state, each raw material liquid A, B circulates in each raw material tank, and the cleaning liquid C from the lines 10A, 10B is the raw material liquid in the lines 16A, 16B. A, B,
And the residual casting liquid in the mixer is supplied to the mold 21 through the valve V2.

(7) Casting end-cleaning liquid collecting step The valves V2 and V3 are simultaneously switched to the F state. Mold 21
Although the supply of the casting liquid to V is stopped, the supply of the cleaning liquid from V1 is continued, and the residual casting liquid in the mixer M1 and the lines 18 and 23 is pushed out to the recovery mixer M2. The cleaning liquid to the valve V2 is returned to the cleaning liquid tank CT through the lines 10C and 22. Since the recovery liquid D is supplied to the mixer M2 by switching the valve V3, the casting liquid-containing cleaning liquid is dissolved and mixed, and is received in the recovery liquid tank through the lines 25 and 30. When the valve V3 is switched to the G state from this state, the process returns to the first in-pipe line cleaning step. The valve operation described above is repeated for each casting operation. In addition, since the liquid amount in the recovery liquid tank CT increases little by little in each cycle, it is preferable to provide an appropriate discharging means. By constructing each valve with a solenoid valve, it is possible to shorten the connecting pipeline and operate it remotely.

[0017]

[Effects] In the device of the present invention, the residual casting liquid in the pipe line is washed and removed by the washing liquid for each casting by the sequential switching operation of the three valves, and the cleaning drainage liquid having a relatively high casting liquid concentration is removed. Since it is dissolved in the recovery liquid and recovered in the recovery tank, and the low-concentration waste liquid thereafter is returned to the cleaning liquid tank, the cleaning liquid tank is less contaminated and the consumption of the cleaning liquid is small, which is economical. Furthermore, since the casting liquid injected into the mold does not contain a recovery liquid or a cleaning liquid, a high-purity casting product can be obtained even in a small amount of production. INDUSTRIAL APPLICABILITY The device of the present invention can be widely used not only as a casting device but also as a reactive liquid mixing device.

[Brief description of drawings]

FIG. 1 is an overall piping diagram of the device of the present invention.

FIG. 2 is a sectional view of a two-way five-way switching valve used in the device of the present invention in an F state.

FIG. 3 is a cross-sectional view of the switching valve in the G state.

FIG. 4 is a sectional view of a main part of the line mixer.

[Explanation of symbols]

 A and B are raw material liquids C are cleaning liquids D are recovery liquids PA, PB, PC and PD are fixed amount supply devices M1 is a casting liquid mixer M2 is a recovery mixer V1 is a raw material valve V2 is a casting valve V3 is a recovery valve

Claims (1)

[Claims] 1. A plurality of raw material valves V1 which respectively form a circulation path and are connected to a plurality of raw material tanks and a cleaning liquid tank, a raw material mixing casting mixer M1 which is connected to a secondary side of the raw material valves, and the mixer. A casting valve V2 that is connected to the discharge port of the casting liquid tank to form a circulation path and is connected to the cleaning liquid tank, a mold connected to the valve, and a secondary side line of the casting valve to one inflow port. A casting liquid recovery mixer M2 connected thereto, and a recovery valve V3 connected to the cleaning liquid tank while forming a circulation path in the recovery liquid tank and connected to the other inlet of the recovery mixer M2. The discharge port of the recovery mixer is connected to the recovery valve, and the casting liquid remaining in the casting liquid passage pipe including the casting mixer is switched by switching each valve for each casting. Is washed with a washing liquid, and the washing liquid containing the casting liquid is mixed with a recovery liquid to Reactive low pressure mixing casting apparatus characterized by recovering the Osamueki tank.