JPH0563817U - Heating cylinder temperature controller for injection molding machine - Google Patents

Abstract

(57) [Summary] [Purpose] To improve molding quality. [Structure] By interlocking at least two of the switching valves 25 to 28 for opening / closing control, a high-temperature or low-temperature heat medium is separately and non-backflowable from the high heat medium source 52 or the low heat medium source 53 to the second zone. Independently supplied and meticulously temperature controlled.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a heating cylinder temperature control device for an injection molding machine, that is, a heating cylinder temperature control device for an injection molding machine, which is used for controlling the temperature of a molten resin.

[0002]

[Prior Art]

 For example, in an injection molding machine for thermosetting resin, a flow passage consisting of grooves and pipes is formed on the outer circumference of the heating cylinder, and an injection medium that controls the temperature of the heating cylinder by circulating a heat medium in this flow passage. There is a molding machine. Next, a conventional example of the heating cylinder temperature control device of this type of injection molding machine will be described below.

FIG. 10 shows a conventional example of a heating cylinder temperature control device for an injection molding machine. A heating cylinder 1 is provided with a flow passage 2 in the heating cylinder 1. The flow passage 2 is formed by a groove (not shown in the figure to the white arrow in FIG. 10) formed on the outer periphery of the heating cylinder 1, three switching valves 3 and 4 having 5 ports, and pipe lines 6 to 12. Inflow ports 13 and 14 and outflow ports 15 and 16 are provided at the ends of the.

The flow passage 2 is divided into four zones of a first zone I, a second zone II, a third zone III and a fourth zone IV from the nozzle 17 side along the raw material conveying direction of the heating cylinder 1. Has been divided.

The heat medium is made of a liquid such as oil and water, and has a relatively high temperature heat medium (hereinafter referred to as a high heat medium) and a relatively low temperature heat medium (hereinafter referred to as a low heat medium). The high heat medium flows between the inflow port 13 and the outflow port 15, that is, in the first zone I and the second zone II.

On the other hand, a low heat medium flows between the inflow port 14 and the outflow port 16, that is, in the third zone III and the fourth zone IV. As a result, the flow directions of the high-heat medium and the low-heat medium are switched between the above four zones based on the switching operation of the switching valves 3, 4, and 5, so that the six heating zones shown in (A) to (F) below are used. The temperature of the tube 1 is controlled.

The alphabets A to F described below represent the characters written in the white arrows in FIG. 10, and the heat medium flow direction determined by the position based on the operation of each switching valve 3 to 5. Is shown.

(A) The switching valve 3 / position A, the switching valve 4 / position C, and the switching valve 5 / position E are switched to a high temperature in the first zone I and the second zone II, and the third zone III and the third zone III. Each of the 4 zones IV is controlled to a low temperature.

(A) The switching valve 3 / position A, the switching valve 4 / position C, and the switching valve 5 / position F are switched, and the first zone I and the second zone II are temperature-controlled to a high temperature. A low heat medium is not circulated in III, and the temperature is controlled to be low in the fourth zone IV.

(C) The switching valve 3 / position A, switching valve 4 / position D and switching valve 5 / position E are switched to a high temperature in the first zone I and the second zone II, and a low temperature in the third zone III. The temperature is controlled to be low, and the low heat medium does not flow through the fourth zone IV.

(D) The switching valve 3, the position B, the switching valve 4, the position C, and the switching valve 5, the position E are switched, the temperature of the first zone I is controlled to a high temperature, and the high heat medium is stored in the second zone II. Are not circulated, and the temperature is controlled at low temperature in the third zone III and the fourth zone IV.

(E) Switching to the switching valve 3 / position B, switching valve 4 / position C and switching valve 5 / position F, the temperature of the first zone I is controlled to a high temperature, and the heating medium of the second zone II is heated. Is not circulated, the low heat medium is not circulated in the third zone III, and the temperature of the fourth zone IV is controlled to a low temperature.

(F) The changeover valve 3 / position B, the changeover valve 4 / position D and the changeover valve 5 / position E are changed over, the temperature of the first zone I is controlled to a high temperature, and the high heat medium is included in the second zone II. Is not circulated, the temperature of the third zone III is controlled to a low temperature, and the low heat medium is not circulated to the fourth zone IV.

By the way, the temperature control of the above-mentioned second zone II is extremely important in order to obtain a good molded product, and this tendency is more remarkable as the injection amount becomes smaller and the heat history becomes smaller. Need temperature control.

[0015]

[Problems to be solved by the device]

 However, since the first zone I is located near the nozzle 17, the temperature is constantly adjusted to a high temperature as shown in (a) to (f) above, while the second zone II is above (a) above. Or, as shown in (c), the high heat medium is circulated, or as shown in (d) or (f), the circulation of the high heat medium is prohibited. It was

From this, when the high heat medium does not flow, it is affected by the high heat medium flowing in the adjacent first zone I, and the cooling control by the environmental temperature is extremely inefficient, and substantially Could not regulate the cooling control of the second zone II, that is, the second zone II at low temperature.

As a result, since the temperature of the second zone II cannot be carefully adjusted, there is an economic problem that defective molding is likely to occur.

Therefore, an object of the present invention is to provide a heating cylinder temperature control device for an injection molding machine, which can maintain a molded product in stable quality.

[0019]

In order to achieve the above-mentioned object, the present invention relates to a high heat medium source 52 and a high heat medium source 52 which are connected to switching valves 25 to 28 in FIG. 1 and store at least a relatively high temperature heat medium. A medium supply source 52, 53 comprising a low heat medium source 53 for storing a heat medium having a lower temperature than the heat medium of the medium source 52 is provided, and each of the heat mediums is separately supplied to the flow passage 19 from the medium supply sources 52, 53. An opening / closing control means 51 for interlocking control of at least two of the switching valves 25 to 28 is provided in order to make the backflow impossible.

[0020]

[Work]

 Since the present invention is configured as described above, the opening / closing control means 51 controls at least two of the switching valves 25 to 28 in order to separately and non-reversely flow through the flow passages 19 of the heat medium. It is possible to prevent the high heat medium and the low heat medium from flowing into the same flow passage 19, and the temperature can be directly controlled by the heat medium supplied from the high heat medium source 52 or the low heat medium source 53.

[0021]

【Example】

 An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a heating cylinder temperature control device for an injection molding machine according to the present invention. A heating cylinder 18 is provided with a flow passage 19 in the heating cylinder 18.

The flow passage 19 is composed of grooves 20 to 24 shown by broken lines and switching valves 25 to 28 having three ports and pipes 29 to 49, and illustration of the inflow port and the outflow port is omitted. Illustration of the inflow port and the outflow port of the flow passage 19 is omitted, and the grooves 20 to 24 are formed on the outer circumference of the heating cylinder 18.

The flow passage 19 is divided into four zones (described later) from the nozzle 50 side along the raw material conveying direction of the heating cylinder 18, that is, a first zone, a second zone, a third zone and a fourth zone. ing.

Reference numeral 51 is an opening / closing control means, and the opening / closing control means 51 has a CPU and a memory (both not shown) as main components, and mainly switches the switching valves 25 to 28 shown in FIGS. 2 and 3 in accordance with the temperature of the heating cylinder 18. It has a function to control opening and closing. A sensor for detecting the temperature of the heating cylinder 18 is not shown.

Further, 52 is a high heat medium source, and 53 is a low heat medium source. The high heat medium source 52 stores a high heat medium made of a liquid such as oil, while the low heat medium source 53 is a low heat medium made of a liquid such as water. To store. The temperature of each heat medium is determined according to the molded product, and the temperature is appropriately adjusted by a heater or a cooler (both not shown) provided in each medium source 51, 52.

The change-over valves 25 to 28 are composed of 3-port / 3-position valves in this embodiment, and are controlled to be opened / closed by a solenoid (not shown). It is connected to the.

As a result, the control signal of the switching valves 25 to 28 can be input from the opening / closing control means 51 to the solenoid. Particularly, in the switching valves 25 and 26 shown in FIG. 2, the opening / closing control means 51 interlocks the switching valves 25 and 26 with the solenoid (details will be described later).

The high heat medium source 52 causes the high heat medium to flow out from the pipe 29, and is reduced via the pipe 33, and the low heat medium source 53 causes the low heat medium to flow out from the pipe 37, while being reduced via the pipe 46. It

The conduit 29 is connected to the conduit 30 and the conduit 34, which together with the conduits 31, 32 and the grooves 20, 21 form a first zone. In the first zone, since no valve body is provided in the middle of the pipelines 29 to 33 and the grooves 20 and 21, the high heat medium is always circulated.

The pipeline 34 is connected to the pipeline 36 and the pipeline 48 via the switching valve 26, the pipeline 36 is connected to the groove 22 and the pipeline 35, and the pipeline 35 is connected to the switching valve 25. Connected to pipelines 33 and 43.

The switching valves 25, 26, the pipe lines 35, 36 and the groove 22 form a second zone, and the switching valves 25, 26 are in the first state and the second state via the solenoid by the opening / closing control means 51. Either is formed.

As a result, the switching valves 25 and 26 form the flow passage 19 of (a) described below when the solenoid is in the first state, while the switching valves 25 and 26 flow in (b) when the solenoid is in the second state. Forming a path 19.

(A) The switching valve 25 connects the pipeline 33 and the pipeline 35, and the switching valve 26 communicates the pipeline 34 and the pipeline 36 (see the solid line in FIG. 3). At this time, the high heat medium flows from the high heat medium source 52 to the second zone via the conduit 19. (B) The switching valve 26 connects the pipeline 43 and the pipeline 35, and the switching valve 26 communicates the pipeline 48 and the pipeline 36 (see the phantom line in FIG. 3). At this time, the low heat medium flows from the low heat medium source 53 to the second zone via the pipe 37 and the pipes 46 and 47.

Although FIG. 2 shows the third state of the solenoid and shows that the switching valves 25 and 26 are in the closed state, in the present embodiment, the switching valves 25 and 26 are the switching control means 51 and the solenoid. It will not be closed by a noid.

Further, the opening / closing control means 51 interlocks the switching valves 25 and 26 by the control of the solenoid to form each of the states (a) and (b), and the following (c) and (d) are shown. ) States are not formed.

(C) The switching valve 25 connects the pipeline 33 and the pipeline 35, and the switching valve 26 communicates the pipeline 48 and the pipeline 36.

(D) The switching valve 26 connects the pipeline 43 and the pipeline 35, and the switching valve 26 communicates the pipeline 34 and the pipeline 36.

Accordingly, the opening / closing control means 51 prohibits the states of (c) and (d) by controlling the opening / closing of the switching valves 25 and 26 in an interlocking manner, and the high heat medium source 52 or the low heat medium source 53 is operated. Each of the plurality of heat mediums supplied is separately circulated in the flow passage 19 in a non-backflowable manner. Further, the opening / closing control means 51 controls opening / closing of the switching valve 27 and the switching valve 28 individually via the solenoids.

That is, the switching valve 27 connects the pipe line 44 and the pipe line 41 when the solenoid is driven and controlled by the opening / closing control means 51 to the first state, and the pipe line 49 and the pipe line 41 in the second state. The channels 41 are communicated with each other, and in the third state, the channel 44 and the channel 41 are communicated with the channel 49 and the channel 41 at the same time.

Further, the switching valve 28 makes the pipe 40 and the pipe 38 communicate with each other when the solenoid is driven and controlled by the opening / closing control means 51 to the first state, and the pipe 39 and the pipe 39 in the second state. And the pipeline 38 are communicated with each other, and in the third state, the pipeline 40 and the pipeline 38 are communicated with the pipeline 39 and the pipeline 38 at the same time.

Further, a pipe line 45 is connected to the pipe line 48, and the third zone is formed by the pipe lines 44, 45, the switching valves 26, 27 and the groove 23. The switching valve 27 is connected to the pipe line 41, and the pipe line 41 is connected to the pipe lines 40 and 42.

The fourth zone is composed of the groove 24, the conduits 39, 42 and the switching valve 28, and the switching valve 28 is connected to the conduit 37 and the conduit 43.

The heating cylinder temperature control device of the injection molding machine configured as described above is capable of switching the switching valves 25 to 28 by the opening / closing control means 51, so that the following six types (1) to (6) will be described. The temperature of the heating cylinder 18 is controlled.

(1) The switching valves 25 and 26 connect only between the pipeline 33 and the pipeline 35, and the switching valves 27 and 28 connect between the pipeline 44 and the pipeline 41 and between the pipeline 49 and the pipeline 41. When the spaces are communicated with each other, the temperatures of the first zone and the second zone are controlled to be high, and the temperatures of the third zone and the fourth zone are controlled to be low (see FIG. 4).

(2) In the case where the switching valves 25 and 26 communicate only between the pipeline 33 and the pipeline 35 and the switching valves 27 and 28 communicate only between the pipeline 49 and the pipeline 41, The zone and the second zone are temperature-controlled to a high temperature, the low-heat medium is not passed through the third zone, and the fourth zone is a low-temperature control (see FIG. 5).

(3) When the switching valves 25 and 26 communicate only between the pipeline 33 and the pipeline 35 and the switching valves 27 and 28 communicate only between the pipeline 44 and the pipeline 41, the first zone and The second zone is controlled to a high temperature and the third zone is controlled to a low temperature, and the low heat medium does not flow in the fourth zone (see FIG. 6).

(4) The switching valves 25 and 26 connect only between the pipeline 34 and the pipeline 36, and the switching valves 27 and 28 connect between the pipeline 44 and the pipeline 41 and between the pipeline 49 and the pipeline 41. When the spaces are communicated with each other, the first zone is temperature-controlled to a high temperature, the second zone is temperature-controlled to a low temperature, and the third zone and the fourth zone are temperature-controlled to a low temperature (see FIG. 7). ).

(5) In the case where the switching valves 25 and 26 communicate only between the pipeline 34 and the pipeline 36 and the switching valves 27 and 28 communicate only between the pipeline 49 and the pipeline 41, The zone is temperature-controlled at a high temperature, the second zone is temperature-controlled at a low temperature, the low heat medium is not passed through the third zone, and the fourth zone is temperature-controlled at a low temperature (see FIG. 8).

(6) In the case where the switching valves 25 and 26 communicate only between the pipeline 34 and the pipeline 36 and the switching valves 27 and 28 communicate only between the pipeline 44 and the pipeline 41, The zone is temperature-controlled to a high temperature, the second zone is temperature-controlled to a low temperature, the third zone is temperature-controlled to a low temperature, and the low heat medium does not flow to the fourth zone (see FIG. 9).

As described above, since the opening / closing control means 51 causes the plurality of heat mediums to separately flow in the flow passage 19 by the switching valves 25 to 28 and cannot flow backward, the high heat medium and the low heat medium have the same flow passage 19. It is possible to prevent the heat from flowing into the chamber and to directly control the temperature by the heat medium supplied from the high heat medium source 52 or the low heat medium source 53.

In particular, although the temperature of the first zone is always adjusted to a high temperature, the temperature of the second zone is directly adjusted by the high heat medium or the low heat medium, so that the influence of the first zone on the temperature is suppressed. To be done.

4 to 9, the opening / closing control means 51, the high heat medium source 52, and the low heat medium source 53 are not shown.

By the way, the above-mentioned temperature control of the second zone is extremely important in order to obtain a good molded product, and this tendency is more remarkable as the injection amount is smaller and the heat history is smaller. Requires temperature control.

[0054]

[Effect of the device]

 Since the present invention is configured as described above, the temperature can be directly controlled by the high heat medium or the low heat medium without the high heat medium and the low heat medium flowing in the same flow passage. As a result, the temperature of the second zone described above can be carefully adjusted, so that a good molded product can be easily obtained even with a small injection amount and a small heat history, and the occurrence rate of defective products can be suppressed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of the switching valve of FIG.

FIG. 3 is a block diagram showing a schematic configuration of a switching valve different from that in FIG.

FIG. 4 is a block diagram showing a usage state of the apparatus of FIG.

FIG. 5 is a block diagram showing a state different from FIG.

FIG. 6 is a block diagram showing a state different from that of FIG.

FIG. 7 is a block diagram showing a state different from that of FIG.

FIG. 8 is a block diagram showing a state different from FIG.

9 is a block diagram showing a state different from FIG.

FIG. 10 is a block diagram showing a conventional example.

[Explanation of symbols]

 18 Heating cylinder 19 Flow path 25-28 Switching valve 51 Open / close control means 52 High heat medium source 53 Low heat medium source

Claims (1)

[Scope of utility model registration request] 1. A heat medium flow passage is provided at a plurality of positions along a raw material conveying direction of a heating cylinder with a plurality of changeover valves having a plurality of ports interposed, and the flow passage is provided in response to opening and closing of the changeover valve. In a heating cylinder temperature control device of an injection molding machine for switching the flow direction of a heat medium, a high heat medium source connected to the switching valve and storing at least a relatively high temperature heat medium, and a heat medium of the high heat medium source A medium supply source comprising a low heat medium source for storing a low temperature heat medium, and at least two of the switching valves for separately and non-backflowing each of the heat medium from the medium supply source to the flow passage. A heating cylinder temperature control device for an injection molding machine, which is provided with an opening / closing control means for interlocking control.