JPH0671728B2 - Mold temperature controller - Google Patents

Description

TECHNICAL FIELD The present invention relates to a mold temperature controller for appropriately controlling the temperature of a mold used in injection molding of plastics, and in particular,
A tank for temporarily storing temperature-controlled water, a pump unit for supplying the temperature-controlled water to the mold, a temperature-controlled water piping system for connecting the tank, the pump unit and the mold, and cooling water from the cooling water piping system. The present invention relates to a mold temperature controller having a cooling water supply pipe line for supplying water and a cooling water return pipe line for discharging cooling water from a tank to a cooling water pipe system and having a temperature control automatic valve provided on the way.

[Prior Art] In plastic injection molding, the temperature of the mold has a great influence on the accuracy of the product. Therefore, in order to adjust the mold temperature to a predetermined value, various mold temperature controllers have been proposed.

FIG. 4 shows an example of such a conventional mold temperature controller. A conventional mold temperature controller, which is surrounded by a one-dot chain line and is generally denoted by reference numeral 1, has a tank 3 having a heater 2 built therein and a pump unit 4. Here, the cooling water is supplied from the water supply side pipe CW1 of the cooling water piping system CW to the cooling water supply pipe line L1.
Water is supplied to the tank 3 via. The supplied cooling water passes through the tank 3, is heated, and is sent to the pump unit 4 via the pipe line L2 as temperature control water for controlling the temperature of the mold 5 (refers to water other than cooling water). It The temperature-controlled water is pressurized by the pump unit 4, is given a head, and is sent to the mold 5 through the pipe line L3 to heat the mold 5 (at this time, the temperature of the temperature-controlled water decreases). Returned to tank 3 via line L4. On the other hand, when cooling, the solenoid valve 6 may be opened to connect the drain side pipe CW2 of the cooling water pipe system CW to the pipe line L5.
This controls the temperature. The fourth
Reference numerals 7 and 7 in the figure are manual valves for closing the pipe lines L3 and L4 when the mold 5 is replaced.

When the operation of the mold temperature controller 1 is in a steady state, the temperature-controlled water returned to the tank 3 via the line L4 is sufficiently mixed with the cooling water supplied to the tank 3 via the line L1. If it is not, the water temperature of the temperature control water flowing through the pipe line L3 is not constant, so that the temperature of the mold cannot be adjusted to a desired value.
In addition, after the temperature-controlled water and the cooling water merge, the temperature change on the downstream side is large. That is, the water temperature of the temperature control water flowing through the pipe line L3 is not constant, and the temperature control of the mold becomes defective. Here, if the tank 3 is enlarged, the temperature fluctuation can be moderated. However, if the size of the tank 3 is increased, the size of the mold temperature controller 1 becomes large, which is contrary to the basic design requirement that the mold temperature controller be compact.

Further, as other conventional techniques, JP-A-62-198418 and JP-A-62-1380005 describe a technique in which the inside of a tank is agitated by temperature-controlled water.

However, in all of these techniques, an external mechanism such as a static mixer or a shock absorber is provided, and the stirring efficiency in the tank is improved by the external mechanism. Therefore, the entire mold temperature controller is enlarged by the amount of the external mechanism,
It becomes impossible to meet the basic design requirement of compactness.

[PROBLEMS TO BE SOLVED] The present invention has been proposed in view of the above-mentioned drawbacks of the prior art, and the temperature supplied to the mold can be increased without increasing the tank capacity for mixing or the size of the entire apparatus. It is an object of the present invention to provide a mold temperature controller that can maintain water conditioning at a desired constant temperature.

[Means for Solving the Problems] According to the present invention, a tank for temporarily storing temperature-controlled water,
A pump unit that supplies temperature-controlled water to the mold, the tank, the pump unit, and a temperature-controlled water piping system that connects the mold,
A cooling water supply line for supplying cooling water from the cooling water piping system,
In a mold temperature controller that discharges cooling water from a tank to a cooling water piping system and has a cooling water return pipeline with a temperature control automatic valve provided in the middle of the cooling water piping system, the nozzle of the temperature control water piping system is The tank is inclined with respect to the center line of the tank and the cutting line of the side wall of the tank so that the inside of the tank is completely agitated by the temperature-controlled water when returning the water to the inside of the tank.

Further according to the present invention, the temperature control water piping system, in addition to the temperature control water conduit for introducing the temperature control water returning from the mold into the tank,
It has a branch flow pipe line that bypasses a part of the temperature-controlled water from the pump unit to the tank without passing through the mold.

Further, according to the present invention, a tank for temporarily storing the temperature-controlled water, a pump unit for supplying the temperature-controlled water to the mold, the tank, the pump unit, a temperature-controlled water piping system for connecting the mold, Gold having a cooling water supply pipe for supplying cooling water from the cooling water pipe system and a cooling water return pipe for discharging cooling water from the tank to the cooling water pipe system and having an automatic temperature control valve in the middle thereof In the mold temperature controller, the temperature control water piping system includes a temperature control water conduit for introducing the temperature control water returning from the mold into the tank and a branch conduit for bypassing the temperature control water to the tank without passing through the mold. The nozzle of the tube is arranged parallel to the center line of the tank, and the other nozzle is arranged radially inward on the side surface of the tank.

Further, according to the present invention, the temperature-controlled water returned into the tank by either the temperature-controlled water return pipe or the branch flow pipe is injected in the tangential direction of the curved surface on the side portion of the tank. ing.

[Operation of the Invention] According to the mold temperature controller of the present invention having the above-described configuration, the stirring in the tank is performed by injecting the temperature-controlled water returning into the tank into the tank. Therefore, suitable agitation can be achieved without using a special external device. More specifically, according to the present invention, the cooling water and the temperature-controlled water in the tank are used by injecting the head of the temperature-controlled water, which is returned into the tank, as an agitating energy in a proper direction as a jet flow. Thus, back mixing, that is, complete stirring is performed. Then, the cooling water and the temperature-controlled water are instantly and uniformly mixed without being unevenly distributed in the tank, and the temperature change at the time of mixing becomes gentle. Therefore, the water temperature of the temperature control water supplied to the mold can be maintained at a desired constant value without increasing the size of the tank, and the quality of the product molded by the mold is also improved.

Further, according to the present invention, the temperature control water is injected substantially tangentially to the center line of the tank and the circumferential surface of the tank by mounting the pipe in an inclined manner,
Helps complete agitation in the tank.

As a result, according to the present invention, complete stirring in the tank is achieved without using an external mechanism such as a static mixer or a shock absorber.

On the other hand, since no external mechanism is used, the size of the mold temperature controller can be made smaller than that of the prior art, and it is possible to meet the demand for making the mold temperature controller as a whole compact.

In the practice of the present invention, if a branch flow line is provided for bypassing a part of the temperature-controlled water from the pump unit to the tank without causing the mold to flow, the total pressure head provided by the pump unit can be operated at a high speed. It is converted into a head, and the speed head can effectively agitate the inside of the tank, and the energy is effectively used. That is, the branch flow pipe is attached to the outer peripheral portion of the tank at an appropriate position and angle, and the temperature-controlled water flowing therein is returned to the inside of the tank, whereby the complete stirring in the tank is sufficiently performed.

In addition, in this specification, the word "Ehedo" means a speed head,
It is used as a concept that includes a pressure head.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. In the figure, the same members as those in FIG. 4 are designated by the same reference numerals.

The cylindrical tank 12 of the mold temperature controller 10 has a built-in heater 14, and a pipe 16 is provided from the water supply side pipe CW1 of the cooling water pipe system CW.
Cooling water is supplied via the. The cooling water supplied into the tank 12 is uniformly mixed with the temperature-controlled water returned into the tank 12 in a manner described later, and if necessary, the heater 14
Is heated to and is sucked into the pump unit 20 as temperature-controlled water via the pipe 18. This temperature controlled water is provided with the necessary pressure head by the pump unit 20 to heat the mold 24 via line 22 and the tank 12 is returned via line 26. When the mold temperature controller 10 is used as cooling water for the mold 24, the heater 14 may be omitted.

A nozzle 28 is provided in the pipeline 26, and the temperature-controlled water passing through this nozzle has a high speed head, and the tank 12
It is poured into and stirred inside. On the other hand, the above-mentioned pipeline 22
Is branched into a branch flow pipe line 30 on the protruding side of the pump unit 20. A predetermined amount of the temperature control water projected from the pump unit 20, for example, 5% to 15% is provided in the branch flow pipe 30.
%, Only through the branch flow line 30. The tip of the branch flow pipe 30 is a nozzle 34, and this nozzle 34 is inclined at an acute angle with respect to the axis of the tank 12 as shown in FIG. 1, and is shown in FIG. Thus, it is mounted substantially tangential to the circumferential surface of surface 13 of tank 12. As a result, the temperature-controlled water bypassed by the branch flow pipe 30 is squeezed by the nozzle 34 and returned to the tank 12 as a jet flow, and its velocity head carries a large amount of water by the ejector effect, thereby causing the tank to flow. The inside is stirred.

In FIG. 1, reference numerals 36 and 38 denote manual valves, respectively. A manual valve 36, 38 is provided to close the conduits 36, 38 when the mold 24 is replaced. In this case, if there is a branch flow pipe, that is, a minimum flow pipe, the mold 24 can be replaced without stopping the operation of the pump unit 20.

The cooling water supplied to the tank by the pipe 16 is
And the temperature-controlled water returned by the branch flow pipe 30 mixes or stirs instantaneously and uniformly (complete stirring).
As a result, the temperature change caused by mixing the cooling water and the temperature-controlled water becomes gentle, and the temperature of the temperature-controlled water supplied from the pipe line 22 to the mold 24 is maintained at a predetermined value. As a result, the mold
The dimensional accuracy and quality of the article molded by 24 are improved.

The temperature-controlled water returned from the tank 12 to the drain-side pipe CW2 of the cooling-water pipe system CW flows through a pipe line 38 provided with the automatic temperature control valve 36.

Here, the branch flow line 30 can be omitted in order to achieve complete stirring in the tank 12 only by the temperature-controlled water returning from the line 26. However, the temperature, energy, etc. of the temperature-controlled water flowing through the pipeline 26 may vary depending on how the mold 24 is. Therefore, in the illustrated embodiment, a minimum flow pipe, that is, a branch flow pipe line 30 is provided. This is because the branch flow pipe 30 is provided on the discharge side of the pump unit 20, and the pressure head of the water flowing therethrough is high and easy to use. Note that the reference numeral 40
Is a temperature sensor. This temperature sensor 40 is the tank 12
It can be provided not only inside but also in the vicinity of the pipe line 18, the pump unit 20, etc., and it is preferable to provide it in the vicinity of the tank 12 as much as possible.

To achieve complete agitation in tank 12, line 26 and branch flow line 30 may be attached to tank 12 in various ways. The manner in which the pipe 26 and the branch flow pipe 30 are attached to the tank 12 will be described below.

3A, 3B, and 3C show a mode in which the temperature-controlled water is returned to the cylindrical tank 12 to realize complete stirring.

In FIG. 3A, reference numeral 42 is the conduit 26 and the branch flow conduit 30.
From FIG. 1, the tank 12 shows a jet of temperature-controlled water that is returned. As is apparent from FIG. 3A, the jet flow 42 is inclined at an acute angle θ with respect to the direction of the center line C of the tank 12 and is inclined at the side wall cut line T. The temperature-controlled water jet 42 returned into the tank 12 at such an angle completely agitates the inside of the tank 12.

FIG. 3B shows two jets 44 and 46 (jets of temperature-controlled water returned to the inside of the tank 12 via the pipe 26 or the branch flow 3) in the tank 12.
In order to explain the state of returning to the inside, the spray 44 is the upper surface of the tank 12.
It is injected parallel to the central axis C at a position near the outer periphery of 13A. On the other hand, the jet flow is injected radially inward on the side surface 13 of the tank 12. Since the jet flow 44 stirs the inside of the tank 12 as a vector in the longitudinal direction, that is, the vertical direction, and the jet flow 46 stirs inside the tank 12 as a vector in the tangential direction, that is, a horizontal direction, perfect stirring is realized by the synergistic action of the two. It is.

FIG. 3C achieves complete stirring by the same principle as FIG. 3B, but the jet flow 44 is injected from the center of the bottom surface 13B of the tank 12.

In any of the above embodiments, a sufficient stirring effect can be obtained with a simple structure in which the temperature control water is inclined toward the wall of the tank when it is returned to the tank.

[Effects of the Invention] As described above, the present invention has the following excellent effects.

(I) Since the inside of the tank is completely agitated by the temperature-controlled water returned to the tank, the temperature of the temperature-controlled water supplied to the mold is also maintained at a certain value.

(Ii) The temperature of the mold is maintained at a desired value, and the quality of the molded product is improved.

(Iii) Since it is a small tank, it does not cause a line flow like a pipe, so the temperature of the temperature-controlled water is stable.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the mold temperature controller of the present invention, FIG. 2 is a partial explanatory plan view thereof, and FIGS. 3A to 3A.
FIG. 3C is an explanatory view showing various modes of returning the temperature controlled water into the cylindrical tank, and FIG. 4 is a block diagram of a conventional mold temperature controller. 10 …… Mold temperature controller, 12 …… Tank, 14 …… Heater,
20 ... Pump unit, 24 ... Mold, CW ... Cooling water piping system, 16, 18, 22, 26, 38 ... Pipe line, 30 ... Branch flow pipe line

Claims (4)

[Claims] 1. A tank for temporarily storing temperature-controlled water, a pump unit for supplying the temperature-controlled water to a mold, a temperature-controlled water piping system for connecting the tank, the pump unit and the mold, and cooling water. Mold temperature with a cooling water supply pipeline for supplying cooling water from the piping system and a cooling water return pipeline for discharging cooling water from the tank to the cooling water piping system and providing a temperature control automatic valve in the middle of the cooling water In the controller, the nozzle of the temperature control water piping system is provided with respect to the tank center line and the side wall of the tank so that the temperature control water completely agitates the tank when returning the temperature control water to the tank. The mold temperature controller is characterized in that the mold temperature controller is inclined. 2. The temperature control water piping system, in addition to the temperature control water conduit for introducing the temperature control water returning from the mold into the tank, causes a part of the temperature control water to pass from the pump unit through the mold. The mold temperature controller according to claim 1, further comprising a branch line that bypasses to the tank. 3. A tank for temporarily storing temperature-controlled water, a pump unit for supplying the temperature-controlled water to a mold, a temperature-controlled water piping system for connecting the tank, the pump unit and the mold, and cooling water. Mold temperature with a cooling water supply pipeline for supplying cooling water from the piping system and a cooling water return pipeline for discharging cooling water from the tank to the cooling water piping system and providing a temperature control automatic valve in the middle of the cooling water In the controller, the temperature control water piping system includes a temperature control water conduit for introducing the temperature control water returning from the mold into the tank and a branch conduit for bypassing the temperature control water to the tank without passing through the mold, and one pipe. No. 2 is arranged parallel to the center line of the tank, and the other nozzle is arranged radially inward on the side surface of the tank. 4. The temperature controlled water returned to the inside of the tank by one of the temperature controlled water return conduit and the branch conduit is injected in the tangential direction of the curved surface of the side portion of the tank.
The mold temperature controller according to the item.