JPH0262227A - Device and method for controlling electric fusion - Google Patents

Abstract

PURPOSE:To apply optimum power to the resistance values of the heating wires of each joint even when the resistance values differ, and to enable electric fusion positively and efficiently by controlling the duty ratio of a power supply applied to the heating wires of the joints and overall conduction time. CONSTITUTION:A light pen 28 for reading a bar code label 26 attached to a joint 24 is connected to a connector 22. A microcomputer 68 interrupts a control signal to the output port of the microcomputer 68 in response to a duty ratio D and the conduction time T set. Since the control signal is amplified and applied to the base of a switching transistor 62, the switching transistor 62 repeats ON/OFF according to the duty ratio D set, and the ON/OFF is continued only for the conduction time T set.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric fusion control device and method, and in particular to a control device and method for electric fusion bonding, and in particular to a joint in which a heating wire is embedded, for example, PE, PP, etc.
Alternatively, the present invention relates to an apparatus and method for controlling the energization time when welding a conduit for gas or water, for example, made of a synthetic resin such as EPPB (hereinafter referred to as a "synthetic resin conduit") and its joint.

[Prior art]

Conventionally, such electric fusion (Electo-Fusio)
A heating wire is embedded in the inner wall of the end of the joint for (n), and after fitting the synthetic resin conduit into the joint, the heating wire is energized to generate heat and melt-join (fusion) the two. arrival)
are doing. In such an EF vertical joint, the type of heating wire (
Since it is complicated to change the resistivity (or specific resistance) depending on the diameter of each pipe, the length of the heating wire, that is, the resistance value, differs depending on the pipe diameter of the joint. On the other hand, for good fusion, both the joint and the synthetic resin conduit need to be appropriately melted, and therefore, considering the difference in resistance, the time to energize the heating wire should be determined according to the pipe diameter. need to be controlled.

Various examples of such time control methods are disclosed in, for example, Japanese Patent Laid-Open No. 58-13 published on August 4, 1988.
No. 1025, JP-A No. 1982-198224 published on October 7, 1985, or December 1988
This method is disclosed in Japanese Patent Application Laid-Open No. 61-274920 published on May 5, 1983.

The first conventional technology adds recognition resistors having different resistance values for different pipe diameters, recognizes the resistance values of the recognition resistors, and sets a predetermined time in a counter accordingly. The energization time is controlled by

The second conventional technology detects the molten state with a sensor,
When the molten state reaches a predetermined state, electricity is cut off.

The third conventional technique compares the current level that initially flows with a previously known current level for each pipe diameter, and controls the entire energization time based on the comparison.

[Problem to be solved by the invention]

The first and third conventional techniques focus on the electrical characteristics of the heating wire and control the energization time accordingly, while the second conventional technique focuses on the volume change during melting and controls the energization time. It is for controlling. In the first and second prior art techniques, it is necessary to add special recognition resistors and sensors, which makes manufacturing of synthetic resin conduits and joints complicated. On the contrary,
In the third conventional technique, although such an additional device can be omitted, it is necessary to compare current levels before full-scale energization, which complicates control.

[Means to solve the problem]

One of the inventions, to put it simply, is a control device for electrically fusing a joint in which a heating wire is buried and a synthetic resin conduit, and for generating electric power to be applied to the heating wire. a power generation means, a data input means for inputting data correlated to the resistance value of the heating wire of the joint, and a duty ratio of the power supply from the power generation means and the overall energization based on the data given from the data input means. The present invention is an electrical fusion control device comprising a control data output means for outputting control data including time, and a control means for controlling power from a power generation means based on the control data.

Another aspect of this invention, to put it simply, is a control method for electrically welding a joint in which a heating wire is buried and a synthetic resin conduit, the method comprising: (a) the resistance value of the heating wire of the joint; (b) based on the data, output control data including the duty ratio and overall energization time of the power source to be applied to the heating wire; This is a method of controlling electrical fusion that intermittents.

[Effect]

For example, the Hercodragel affixed to each joint is read with a light pen, and data related to the resistance value of the heating wire of the joint, such as the pipe type and pipe diameter, are input. For example, control data including the duty ratio of the power supply to be applied to the heating wire and the total energization time is determined from the control data output means including the ROM of the microcomputer, based on its own data. Then, based on the control data, for example, the microcomputer turns on and off the power from the power generation means. Therefore, the duty ratio of the power supply applied to the heating wire of the joint and the entire energization time are controlled. When the power source is AC, not only the total energization time but also the number of cycles per unit time is controlled. In the case of direct current, the duty ratio and energization time are similarly controlled.

〔Effect of the invention〕

According to this invention, the duty ratio of the power supply applied to the heating wire of the joint and the overall energization time are controlled, so even if the resistance value of the heating wire of each joint is different, it is optimal for that resistance value. power is provided, thus making electrofusion possible reliably and efficiently.

Moreover, if the heating wires of all the joints are made of a material with the same resistivity or specific resistance so that the resistance value is uniquely determined by the pipe type and/or pipe diameter, the resistance value correlation data can be used for the pipes. It is only necessary to input data on the species and/or pipe diameter, and there is no need to provide extra means for joints or synthetic resin conduits, unlike in the prior art, and complicated control can be avoided.

Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the accompanying drawings.

(Embodiment) Referring to FIG. 1, a fusion control device 10 according to an embodiment of the present invention includes a casing 12, and a front panel 14 of the casing 12.
A power switch 16 is provided. The front panel 14 also houses a tube type display section 18, which has 1, ED20a, 20b, -, each displaying a different tube diameter (nominal diameter) of different tube types. .

The front panel 14 is further provided with a connector 22, which has a coupling 2 as shown in FIG.
A light bezel 28 (FIG. 3 or FIG. 6) is connected to read the barcode label 26 attached to 4.

Then, the tube type displayed on the barcode label 26 read by the light pen 28 is displayed on the tube type display 18.
The information is displayed by lighting up the corresponding LEDs 20a, 20b, . . . .

Between the tube type indicator 1 day and the connector 22, there is an energization time indicator 30. An abnormality indicator 32 and an operation indicator 34 are arranged. The energization time display 30 is for displaying the energization time and remaining time determined as described below, and is composed of, for example, a two-digit segment display. The abnormality indicator 32 includes display LEDs 36a, 36b, 36c and 36d, and these display LEDs 36a, 36b3
6c and 36d indicate "power supply voltage,""outputvoltage,""wirebreak," and "overcurrent," respectively. The operation indicator 32 includes two display LEDs 38a and 38b, and the display LED 38a indicates that it is in operation ( The display LED 38b displays the end of operation (EDD).

A start switch 40 provided together with the operation display 2S32 is a switch for instructing the start of energization, and a stomp switch 42 is a switch for forcibly stopping energization.

The upper part of the front panel 14 is formed as a storage part 44, and although not shown here, for example, a core cord, an output cord, a light pen, etc. are stored in the storage part 44.

As a joint to which this invention can be applied, °°socket pipe"
There are various types such as ``cheese'', ``elbow'', ``cap'', ``saddle'', or ``reducer''.

FIG. 2 shows a socket as an example, and the joint 24 has a connecting end 46 into which a connecting end 50 of a synthetic resin conduit is inserted. A heating wire 52 is embedded in the inner wall of the connecting end 46 of the joint 24, as shown by the dotted line, and the heating wire 52 is connected to a terminal 54 on the outer periphery of the joint 24. The terminal 54 is connected to the output code 5 of the device shown in FIG.
6 is connected so that the electric heating cotton 52 can be energized.

The above-mentioned barcode label 26 is further affixed to the outer circumference of the joint 24, and the barcode label 26 contains information specific to the joint 24, such as the pipe type and pipe diameter.
It is readable by the light ben 28 and displayed as a barcode.

In this embodiment, heating wires having the same resistivity or specific resistance are used in order to avoid complicating manufacturing even if the type of joint or pipe diameter changes. Therefore, the resistance value of the heating wire 52 as a whole varies depending on the individual joints. Therefore, in order to optimize the energization time depending on each individual joint,
This embodiment attempts to control this.

Referring to FIG. 3, the casing 12 of the fusion control device 10 includes:
A power supply terminal 58 for receiving a power supply of 100V AC is provided, and AClooV from this power supply terminal 58 is applied to a constant voltage circuit 60 of 24V DC, for example. The constant voltage circuit 60 includes a known transformer, a symverter circuit, etc.
These generate DC24V from AClooV. The output voltage from this constant voltage circuit 60 is controlled intermittently by a switching transistor 62 to output a voltage at an output terminal 64.
is derived.

For example, a CT (Current Transformer) is used to detect the input voltage from the power supply terminal 58.
), etc., is provided, and the input voltage detection circuit 66 has a predetermined value, for example, 85
When the voltage fluctuates beyond the range of V to 135 cm, a signal is output and given to the microcomputer 68. Further, an overcurrent detection circuit 70 is provided in association with the constant voltage circuit 60, and the overcurrent detection circuit 70 has a specified value that the output current becomes during welding.
For example, when the current exceeds 15 A, a signal is output and given to the microcomputer 68. Furthermore, an output voltage detection circuit 72 is provided at the output of the constant voltage circuit 60, and the output voltage detection circuit 72 detects when the output voltage from the constant voltage circuit 60 exceeds a specified value, for example, 24V±2%. A signal is output and given to the microcomputer 68. A disconnection check transistor 74 is inserted between one of the outputs of the constant voltage circuit 24 and the output terminal 64, and a disconnection detection circuit 76 is connected to the output of the disconnection check transistor 74. . This disconnection detection circuit 76 detects whether or not there is a disconnection between the terminals 54 of the joint 24 to which the output cord 56 is connected, that is, the heating wire 52, by the voltage of the resistor 76a associated with the circuit 76. judge. If the heating wire 52 is disconnected, the disconnection detection circuit 76 outputs a signal to the microcomputer 68.
44. Ru.

In the microcomputer 68, these abnormality detection circuits 6
6.70 When an abnormal state is detected by 72 and 76, as described later, for example, the output from the constant voltage circuit 60 is stopped, and each display LE of the abnormality indicator 32 is
Light up the corresponding ones of D36a to 36d.

A light pen 28 is connected to the aforementioned connector 22 (FIG. 1), and an output signal of the light pen 28 is given to a barcode reading circuit 78. The bar code reading circuit 78 decodes the signal from the light pen 28, converts it to "bi" or "°0", and provides it to the microcomputer 6. Therefore, data on the pipe type and pipe diameter of the joint 24 displayed on the barcode label 26 is input to the microcomputer 68.

Although not shown in FIG. 1 above, a temperature sensor 80 including, for example, a thermistor is provided inside the housing 12.
This temperature sensor 80 detects the temperature of the environment to which the device 10 is grounded. The voltage signal from the temperature sensor 80 is then applied to a temperature detection circuit 82, where it is converted into digital data and applied to the microcomputer 68. In response to the environmental temperature measured by the temperature sensor 80, the microcomputer 6 displays the temperature display 8 shown in FIG.
The display LED 86a, 86b, or 86c included in 4 is turned on, and the energization time is modified (increased or decreased) as described later.

The aforementioned start switch 40 and stop switch 42 are connected to the microcomputer 68, and its outputs are connected to the various indicators 18, 3 shown in FIG.
0.32 and 34 and a temperature indicator 84, which will be described later, are connected.

Referring to FIGS. 5A to 5C, the main routine of FIG. 5A is started in response to turning on the power switch 16. In the first step SL of the main routine, the microcomputer 68 controls each display LED and the energization time display 3.
For a 0 etc., initialize its associated 1, /O port or register.

Subsequently, in step S3, the barcode reading circuit 82
When the barcode input is given from , the microcomputer 68 reads temperature data from the temperature detection circuit 82 in the next step S5.

In the following step S7, the microcomputer 68
Set I10 data. Specifically, the duty ratio is 1 based on the barcode human horn data and temperature data.
Set the energization time etc. in the register.

For example, the standard time and duty ratio (time ratio of energization/cutoff repeated per unit time, for example, 1 second) are set in advance for each tube type displayed on the tube type display 18 in FIG. 1, such as blowing 1. Microcomputer 68 ROM
(not shown).

(Left below) Table 1 In the above table, the duty ratio or time T is
It may be different for each fitting, or it may be common to fittings of multiple types or pipe diameters.

In any case, depending on the temperature, 10Dα, 0 or −D
Add α to the duty ratio in the table above.

For example, if the standard duty ratio of the joint is ``50,'' and the corrected duty ratio Dα is ``10,'' for example, when the environmental temperature is below O'C, the duty ratio is set to '60J (=D+Dα=60+10). Set. For example, when the environmental temperature is between 0°C and 30°C, the duty ratio is set to [50J (-D+Dα-5
0+O), and when the environmental temperature is, for example, 30°C or higher, the duty ratio is 40J (=D+Dα
-50-10), respectively.

Also, depending on the temperature, +Tα, 0 or -Tα is added to the standard time T in the above table. Assuming that the standard energizing time T of a joint made of
The energization time is set as 21 seconds (-T+Tα=16+5). When the environmental temperature is, for example, O''C to 30°C, the energization time is set to 16 seconds (=T + Tα = 16 + O),
Further, when the environmental temperature is, for example, 30° C. or higher, the energization time is set to 11 seconds (−T+Tα=16−5).

With the duty ratio and energization time T set in this way, the start switch 40 (
When the button (FIG. 1) is pressed, the microcomputer 68
In the next step Sll, cycle timer control is performed.

That is, the microcomputer 68 operates according to the set duty ratio and the energization time T described above.
Intermittent the control signal to that output port. This control signal is amplified and applied to the base of the switching transistor 62, so that the switching transistor 62 is repeatedly turned on and off according to the set duty ratio, and the on/off state is maintained for the set energization time T. . Therefore, according to this embodiment, the fusion control device 1
From 0, for example, as shown in FIG. 4, an intermittent voltage of C24V is applied to the heating wire 52 of the joint 24 (FIG. 2).

In this way, by controlling not only the energization time but also the duty ratio, optimum energization control can be performed for each type of pipe diameter. That is, in a joint with a small pipe diameter, the duty ratio is relatively small, but if the energization time is controlled not to be too short, rapid heating can be suppressed when the pipe diameter is small. To be more specific, if a joint with a small diameter pipe is used with the same heating wire as a joint with a large pipe diameter, the overall resistance will be smaller, so if the same amount of electricity is applied, the current will increase and the pipe will heat up faster. It ends up. When the joint is heated rapidly in this manner, the joint is sufficiently melted, but sufficient heat is not transmitted to the synthetic resin conduit to which it is to be joined, and the melting remains insufficient. In this case, naturally the fusion bonding will be poor.

On the other hand, when the overall resistance value is small as in this example, by reducing not only the energizing time but also the duty ratio, welding defects caused by insufficient melting can be effectively prevented. can. Further, when the overall resistance value is large, increasing the duty ratio and lengthening the current application time allows a sufficient amount of heat to be obtained in a shorter time, which is preferable in terms of work efficiency.

Furthermore, by changing the duty ratio and/or the energization time depending on the environmental temperature, reliable fusion can be achieved regardless of the environmental temperature or the existing installation.

Returning to FIG. 5A, then in step S13,
When an abnormality signal is outputted in the abnormality detection routine shown in FIG. 5B or a stomp signal is outputted by pressing the stop switch 42, control is immediately stopped. Then, in step S15, when barcode data is input again for another fusion, the previous steps 35 to S13 are repeated, and when all termination is instructed in step S17, this main routine is terminated. Ru.

Note that the abnormality detection routine shown in FIG. 5B can be easily understood and is not important to the present case, so a detailed explanation will be omitted.

FIG. 6 is a block diagram showing another embodiment of the invention. This embodiment attempts to control the duty ratio and energization time of the AC voltage, whereas the previous embodiment in FIG. 3 was for intermittent DC voltage.

That is, the AClooV applied from the 50 or 60 Hz commercial power supply 84 is stepped down by the transformer 86 and output as AC 24V.

On the primary side of the transformer 86, for example, “°OMRON G3
^-20B'' is inserted, and this syrisk circuit 88 is controlled by the control circuit 90.
Wholesale.

The control circuit 90 includes a power supply circuit 92, and this power supply circuit 92
generates DC5V from AClooV and supplies it to each circuit of the control circuit 90. An input voltage detection circuit 94 is also coupled to the primary side of transformer 86 and, like input voltage detection circuit 66 (FIG. 3) of the previous embodiment, detects abnormal voltages at AClooV. Detect fluctuations.

An output voltage detection circuit 96 and a disconnection detection circuit 98 are coupled to the secondary side of the transformer 86. These circuits 96 and 98 also detect an abnormality in the output voltage and a break in the heating wire 52 (FIG. 2) of the joint 22, similarly to the output voltage detection circuit 72 and the disconnection detection circuit 76 of the previous embodiment. Then, the input terminal detection circuit 94. The respective detection outputs of the output voltage detection circuit 96 and the disconnection detection circuit 98 are provided to an abnormality detection circuit 100, and the abnormality detection circuit 100 provides an abnormality signal to the Cyrisk drive circuit 102. When receiving the abnormal signal, the thyrisk drive circuit 102 controls the thyrisk circuit 88 to disable it.

The thyrisk drive circuit 102 is started in response to a start signal from a start/stop circuit 104 connected to the start switch 40 and the stop switch 42, and stopped in response to a stop signal.

Further, the barcode reading circuit 106 receives a reading signal of the barcode label 26 (FIG. 2) from the light pen 24 and decodes it. Then, the barcode reading circuit 106
Based on the deciphered results, data representing the pipe type and pipe diameter is provided to the duty ratio/time setting circuit 108 as described above. The duty ratio/time setting circuit 108 knows the duty ratio and energization time preset for the pipe type and diameter based on the given data, and accordingly determines the duty ratio and energization time set in advance for the pipe type and pipe diameter, and accordingly
The duty ratio data is given to 02. Therefore, the thyristor drive circuit 102 creates a drive signal based on the given data, and controls firing of the gate of the thyristor included in the thyristor circuit 88.

At this time, the temperature detection circuit 110 connected to the thermistor 80 provides data on the environmental temperature to which the device 10 is grounded at that time to the thyrisk drive circuit 102. Therefore, in the same manner as described above, the thyrisk drive circuit 102 modifies or changes the set duty ratio depending on the temperature, and controls the thyrisk circuit 88 with the changed duty ratio. Therefore, according to this embodiment, an intermittent voltage of 24 VAC as shown in FIG. 7 is output from the output terminal 64. That is, when applying AC power as described above, if the duty ratio is controlled, the number of cycles (number of repetitions) per unit time is controlled.

Further, a timer time is set in the timer circuit 112 based on the time data from the duty ratio/time setting circuit 108, and this timer time is also modified or changed in accordance with the above-mentioned temperature data. Then, the timer circuit 112 displays the timer time on the display 3o.

Then, based on the data from the barcode reading circuit 106, the display setting circuit 114 sets the tube type display LE as shown in FIG.
D20, 20b, ... LED36a ~36.
The lighting of the LED group including d, 38a, and 38b is controlled.

In this embodiment as well, the duty ratio and energization time of the power applied to the heating wire 52 are controlled, so whether the wire has a small diameter or a large diameter, the M purse string can be attached reliably and efficiently.

The results of the fusion experiment according to this example are shown in Blowing 2. In addition, a threaded adapter with a pipe diameter of φ8 was used in the experiment.

Table 2 In the above table, the results are the results of a 90°C hot internal pressure creep test, and the test pressure was 22 kg/c4. In sample 1, the frequency was applied at 60 Hz per second, that is, at a duty ratio of r100 J, without controlling the number of cycles. As a result, leakage occurred in sample 1. On the other hand, in sample 2, the duty ratio r33. (Number of cycles 2
0), and sample 3 was applied with a duty ratio of 8 J (cycle number 5).As a result, samples 2 and 3
In both cases, no abnormality occurred for more than 1000 hours. In this way, even though the total amount of heat is almost the same,
As for the results, there was a big difference between changing the duty ratio and not changing the duty ratio, demonstrating the effectiveness of this example.

In addition, in the embodiment shown in FIG. 6, a microcomputer may be used for control as in the embodiment shown in FIG. 3, or in the embodiment shown in FIG. It may also be configured using a circuit.

Furthermore, as a switching means for turning on and off the power supply, any means other than the switching transistor 62 shown in FIG. 3 and the SIRISC circuit 88 shown in FIG. 6 may be used.

Furthermore, in the above embodiments, a barcode label and a light pen were used as input means.

However, for example, the LEDs 2a, 20 shown in FIG.
Various modifications may be possible, such as configuring b, .

[Brief explanation of the drawing]

FIG. 1 is an illustrative view showing, in particular, the arrangement of the front panel of an embodiment of the present invention. FIG. 2 is a perspective view showing an example of a joint to which the present invention can be applied. FIG. 3 is a block diagram showing an example of the configuration of the fusion control device shown in FIG. 1. FIG. 4 is an illustrative diagram showing an example of an output voltage waveform according to the embodiment of FIG. 5A and 5B are flow diagrams showing the operation of the embodiment of FIG. 3. FIG. FIG. 6 is a block diagram showing another example of the configuration of the fusion control device shown in FIG. 1. FIG. 7 is an illustrative diagram showing an example of the output voltage waveform according to the embodiment of FIG. In the figure, 10 is a fusion control device, 24 is a joint, 26 is a barcode label, 28 is a light pen, 50 is a constant voltage circuit, 62 is a switching transistor, 68 is a microcomputer, 78 is a barcode reading circuit, and 80 is a temperature sensor, 82 is a temperature detection circuit, 88 is a cyrisk circuit,
102 is a thyristor drive circuit, and 108 is a duty ratio.
The time setting circuit is shown. Patent Applicant Kubota Iron Works Co., Ltd. Agent Patent Attorney Yama 1) Yoshihito Diagram Diagram Diagram Diagram 5A Procedural Amendment Written Side 1 Color. December 19, 1988 78 Contents of the Amendment Figures 1 to 7 are revised as shown in the attached sheet. that's all

Claims (1)

[Scope of Claims] 1. A control device for electrically fusing a joint in which a heating wire is embedded and a synthetic resin conduit, comprising power generation means for generating power to be applied to the heating wire. , data input means for inputting data correlated to the resistance value of the heating wire of the joint, based on the data given from the data input means,
control data output means for outputting control data including a duty ratio and a total energization time of the power from the power generation means; and a control data output means for intermittent the power from the power generation means based on the control data. A control device for electrical fusion, comprising an interrupting means. 2. Temperature detection means for detecting an environmental temperature is provided, and the control data generation means includes changing means for changing at least one of the duty ratio and the entire energization time according to the temperature detected by the temperature detection means. An electric fusion control device according to claim 1. 3. A control method for electrically welding a joint in which a heating wire is buried and a synthetic resin conduit, the method comprising: (a) inputting data correlated to the resistance value of the heating wire of the joint; (b) Based on the data, output control data including a duty ratio of a power source to be applied to the heating wire and a total energization time, and (c) intermittent the power source based on the control data.
Control method for electric fusion.