JPH065129Y2 - Mold temperature controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mold temperature controller attached to a plastic molding machine, more specifically, a device capable of detecting and controlling the pressure and flow rate of a temperature adjusting medium. Regarding

(Prior Art) Generally, in a plastic molding machine, it is extremely important to accurately control the temperature of the mold in order to improve the moldability, shorten the molding cycle, and prevent the occurrence of defective products. is there.

In fluid control in which the temperature of the mold is controlled with a fluid such as water or heat-resistant oil, the flow rate and pressure of the fluid that is the specific control target is grasped, and based on this, control means such as output adjustment of the pump is used. Therefore, it is necessary to maintain the flow rate and pressure at appropriate values, and for that purpose, it is an important issue to grasp the pressure and flow rate of the fluid more accurately and accurately.

Conventionally, a pressure gauge is provided near the pump discharge port to measure the pressure and flow rate of a fluid (usually a liquid is used, so a liquid will be described below as an example), and discharge is performed based on the detection value of the pressure gauge. While reading the pressure, there is a correlation between the discharge pressure and the flow rate, and therefore a method of determining the discharge pressure and the flow rate, respectively, has been adopted.

In this type of mold temperature controller, there is no known structure for controlling the discharge pressure and the discharge flow rate of the pump based on the current value of the motor.

(Problems to be solved by the invention) However, in the mold temperature controller of the above-mentioned conventional example, (a) in the following cases, the discharge pressure (discharge flow rate) of the pump is not accurately indicated. There is a drawback that the flow rate of the medium in the medium feeding path cannot be controlled accurately. That is, (a) When the water pressure is exerted on the medium flow when supplying water such as replenishing the medium.

(B) When the boiling point of the medium is lower than the target temperature, pressurizing the medium with a medium tank or the like to raise the boiling point and prevent boiling, and when supplying the high temperature medium to the mold, the medium tank or the like is placed on the downstream side. When it is under pressure.

(C) When drainage pressure is applied to the medium circulation path when the medium is exchanged while circulating the medium to the mold.

Further, (b) in the above-mentioned conventional example, when installing a pressure gauge, it is necessary to connect to a pipe forming a medium feeding path via a branch pipe, so not only is the setting of the pipe cumbersome,
There is a problem that the installation space of the device becomes large.

As disclosed in Japanese Utility Model Publication No. 4-8208, there is known a water supply pump overheat prevention control device which detects a motor current value and controls the discharge amount of the pump based on the detected current value. No configuration is shown that simultaneously outputs the value and the discharge amount and discharge pressure of the pump.

The present invention is intended to solve the problems of the above-mentioned conventional example, and a mold temperature controller capable of accurately grasping the pressure and flow rate of a medium under any condition and ideally controlling the mold temperature based on the pressure and flow rate. To provide.

(Means for Solving Problems) As a means for solving the above problems, the present invention provides a pump that supplies a medium for temperature adjustment to a mold, an electric motor that drives the pump, an electric motor and a power supply. And an electric wire for electrically connecting, connecting an ammeter to an appropriate portion of the electric wire,
A mold temperature controller configured to control a discharge pressure and a discharge flow rate of a pump based on a current value of the ammeter to control a pressure and a flow rate of a medium supplied to the mold, wherein the ammeter In advance, information based on the correlation coefficient between the electric current value of the electric motor and the discharge pressure and the discharge flow rate of the pump is input in advance, and the information of the three values of the current value and the discharge pressure and the discharge flow rate are simultaneously output as a scale or a number. The configuration is characterized by the above.

(Function) The current value flowing from the power supply to the motor is detected by an ammeter, and the discharge pressure and discharge flow rate of the pump are controlled based on the detected values to optimize the flow rate and pressure of the medium supplied to the mold. Adjust.

Since there is a correlation between the discharge pressure and discharge flow rate of the pump and the electric current value of the electric motor, the correlation of these three parties is input as information in advance, and the information of the three parties is simultaneously displayed on an analog scale. , Or digitally display the numbers.

Therefore, according to the present invention, the water supply pressure, the medium tank internal pressure,
Without being affected by disturbance factors such as drainage pressure, the discharge pressure and discharge flow rate of the pump can be easily grasped by the ammeter, and the mold temperature can be controlled more accurately.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

(1) is a mold temperature controller, this mold temperature controller (1),
A pump (2) that supplies a medium (6) such as water or heat-resistant oil for temperature control to the mold (10) (consisting of the core (10c) and the cavity (10d)) of the plastic molding machine, and its pump
An electric motor (3) for driving (2) and a medium tank (4) for accommodating the medium (6) are provided.

The outlet (4a) of the medium tank (4), the pump (2), and the inlet (10a) of the mold (10) of the plastic molding machine are the medium feeding pipe (5a) forming the medium feeding path of the medium (6). Further, the outlet (10b) of the mold (10) and the inlet (4b) of the medium tank (4) are sequentially connected and connected by a medium return pipe (5b) forming a medium return passage. The medium feeding circuit (5a) and the medium returning pipe (5b) are a medium circulation circuit (5).
Are configured. Therefore, by driving the pump (2) with the electric motor (3), the temperature control medium in the medium tank (4)
(6) can be supplied to the mold (10) through the medium circulation circuit (5), and the temperature control medium (6) which has finished predetermined heat exchange by cooling or heating the mold (10), It is returned from the outlet (10b) of the mold (10) to the medium tank (4) via the medium return pipe (5b) of the medium circulation circuit (5) so that the medium (6) can be circulated and reused. There is. In this case, the medium (6) returned to the medium tank (4)
Is heated to a desired temperature by a heater (7) provided above the medium tank (4), or by a temperature control medium (6) newly supplied to the desired temperature from the outside by a medium supply pipe (8). After cooling or not, it is sent to the mold (10) again.
At this time, if the medium (6) becomes excessive or if you want to drain, the medium discharge pipe (9) provided downstream of the outlet of the medium tank (4)
Twist valve (11) can be opened and discharged. The heater (7) can also be used when heating the medium during initial water supply. Reference numeral (12) is a valve for opening and closing the medium (6) to the medium supply pipe (8).

The electric motor (3) is a power source provided outside the mold temperature controller (1).
It is electrically connected to (20) via an electric wire (21). An ammeter (22) is connected to the electric wire (21) at an appropriate position. The ammeter (22) employs an ammeter as shown in Fig. 3 on the front side of the mold temperature controller (1). If the ammeter (22) has a scale (2
3) is attached so that it can be seen from the outside. The scale plate
In (23), as shown in the third figure, after experimentally examining the correlation between the electric current supplied by the electric motor (3) and the discharge pressure and the discharge flow rate of the pump (2), information of these three parties is shown. Are proportionally scaled as a current scale (24), a discharge pressure scale (25) and a flow rate scale (26). Therefore, by the pointer (27) of the scale plate (23), the value of the current flowing through the electric wire (21) is changed to the current scale (24).
At the same time, the discharge pressure and the discharge flow rate of the pump (2) are measured on the discharge pressure scale (25) and the flow rate scale (26), respectively.

What is shown in FIG. 4 is a modification of the scale plate (23) of the ammeter (22). Also in this case, information based on the correlation coefficient between the current value of the electric motor (3) and the discharge pressure and discharge flow rate of the pump (2) is also input to the scale (28) in the same manner as described above. Then, the pointer (27) of the ammeter (22) is adjusted so as to come near the center of the scale (28) of the scale plate (23) at the optimum current value experimentally obtained in advance, and the scale (28 ) Is provided with a belt-shaped normal operation scale (29) with an allowable current value range near its center, an overload scale (30) on the right side, and a low load scale (31) on the left side. According to such a configuration, the electric motor
(3) As a result, the usage status of the pump (2) can be read at a glance, and the mold temperature controller can be used easily.

Since an ammeter is used, cavitation, which has hitherto been found only by vibration of the pump (2) or the electric motor (3), can be easily detected early by a blur of the pointer of the ammeter, and an early countermeasure can be taken.

As the ammeter (22), an analog type ammeter is used in this embodiment, but it goes without saying that a digital type ammeter can also be used. In the latter case, the current value of the electric motor (3) and the discharge pressure and discharge flow rate of the pump (2) are output as numbers.

Further, a microprocessor is connected to the ammeter (22), and the current value detected by the ammeter (22) is converted into a discharge pressure and a discharge flow rate by the microprocessor,
The preset pressure, discharge pressure, and discharge flow rate are compared, and if any errors occur, a signal is sent from the microprocessor to the power supply (20) to drive the motor.
The discharge pressure and the discharge flow rate can be controlled by adjusting the current flowing in (3), and an alarm can be issued together with this.

The discharge pressure and discharge flow rate of the pump (2) are
Ideally, the mold is used because it controls the temperature in (10).
Although it is best to grasp the pressure and flow rate in the pipe inside (10), the pressure near the discharge port of the pump (2) in the above example is taken into consideration in consideration of problems such as cost and simplification of the device. However, the invention can be appropriately implemented only by paying attention to the flow rate and the pressure and flow rate at any place in the medium circulation circuit (5).

Unlike the conventional example, the discharge pressure (discharge flow rate) of the pump is not directly detected and controlled by the pressure gauge, but the discharge pressure of the pump and the medium pressure and flow rate including the discharge flow rate are detected by detecting the current value of the ammeter. Since it is not affected by external pressure such as water supply pressure, medium tank internal pressure, and drainage pressure as in the conventional example, it is possible to always accurately grasp the discharge pressure and discharge flow rate of the pump. The mold temperature can be controlled accurately.

Further, since the ammeter is provided on the electric wire that electrically connects the electric motor and the power source, it is not necessary to install troublesome piping as in the conventional example, and the installation space of the device can be reduced.

(Effect of the Invention) According to the present invention, information based on the correlation coefficient between the current value of the electric motor and the discharge pressure and the discharge flow rate of the pump is input in advance to the ammeter, and the current value, the discharge pressure and the discharge flow rate are input. Since the information of the three is output simultaneously as a scale or a number, the three values of the electric current value of the electric motor and the discharge pressure and the discharge flow rate of the pump are simultaneously displayed as a scale or a number. As a result, the discharge pressure and discharge flow rate of the pump can be easily grasped and adjusted based on the scale or the numbers. Moreover, since it is not affected by disturbance factors such as the water supply pressure, the medium tank internal pressure, and the drainage pressure, the mold temperature can be controlled more accurately.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a schematic process drawing of the whole, FIG. 2 is a schematic perspective view,
FIG. 3 is an explanatory view of the scale plate of the ammeter, and FIG. 4 is an explanatory view showing a modified example of the scale plate of the ammeter. (1) …… Mold temperature controller, (2) …… Pump, (3) …… Motor, (4) …… Medium tank, (5) …… Medium circulation circuit, (6)…
… Medium, (10) …… Mold, (20) …… Power supply, (21) …… Wire,
(22) …… ammeter, (23) …… scale plate, (24) …… current scale,
(25) …… Discharge pressure scale, (26) …… Flow scale, (27) …… Indicator, (28) …… Scale, (29) …… Normal operation scale, (30)…
… Overload scale, (31) …… Low load scale.

Claims (1)

[Scope of utility model registration request] 1. A pump (2) for supplying a medium (6) for temperature control to a mold (10) and an electric motor (3) for driving the pump (2).
And an electric wire for electrically connecting the electric motor (3) and the power source (20)
(21), and an ammeter (22) is connected to an appropriate portion of the electric wire (21), and the discharge pressure and the discharge flow rate of the pump (2) are controlled based on the current value of the ammeter (22). , The medium supplied to the mold (10)
A mold temperature controller configured to control the pressure and flow rate of (6), the ammeter (22), the current value of the electric motor (3) and the discharge pressure of the pump (2) and The mold temperature is characterized in that information based on a correlation coefficient with the discharge flow rate is input in advance, and the current value, the discharge pressure, and the discharge flow rate information of three parties are simultaneously output as a scale or a number. Adjuster.