JPH07164532A - Electric fusing device - Google Patents

Abstract

PURPOSE:To eliminate failure in electric fusion caused by defective insertion of a pipe. CONSTITUTION:In an electric fusing device, a spigot of a thermoplastic resin pipe 17 is fused to a faucet 18 of a joint 16 by supplying electric current to a heat generating body 20 provided on the inner peripheral face of the faucet 18 of the thermoplastic resin joint 16. In the electric fusing device, there is provided an defective insertion detection means for determining that the spigot of the pipe 17 is not properly inserted into the faucet 18 of the joint 16 when a time where a current value flowing to the heat generating body 20 rises to a set current value exceeds a set time. When the detecting means detects a defective insertion of the pipe 17, the supply of the current to the heat generating body 20 is interrupted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe opening made of a thermoplastic resin for receiving a joint of a thermoplastic resin by supplying an electric current to a heating element provided on an inner peripheral surface of the joint. The present invention relates to an electric fusing device for fusing.

[0002]

2. Description of the Related Art Conventionally, even if the pipe opening has not been properly inserted into the receiving port of the joint, the welding operation is performed to the end by operating the start button.

[0003]

However, if the pipe mouth is melt-bonded in a state where it is not properly inserted into the receiving port of the joint, there is a problem in that it is easily separated after the melt-bonding.

[0004]

SUMMARY OF THE INVENTION However, according to the present invention, by supplying an electric current to a heating element provided on the inner peripheral surface of the receiving end of a joint made of a thermoplastic resin, a pipe made of a thermoplastic resin is received at the receiving end of the joint. In an electric fusing device for fusing and welding the insertion hole, when the time for which the current value flowing through the heating element rises to the set current value exceeds the set time, the pipe opening is properly placed in the receiving port of the joint. Equipped with a tube insertion failure detection means for determining that the tube is not inserted, and when the detection means detects a tube insertion failure, the supply of current to the heating element is interrupted, and it is possible to visually judge. A defective tube insertion that cannot be accurately detected, and the fusion welding operation is interrupted when it is detected. It can be done.

[0005]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 is a heat pattern diagram, FIG. 2 is a diagram for explaining the electric fusion welding work, and the reference numeral (1) in FIG. 2 is a controller for the electric fusion welding, and the start button (3) and the stop are provided on the upper surface of the main body case (2) A button (4) and a liquid crystal display (5) are provided, and a plug (6) for connecting to a power source is provided at the tip of a power cord (7) and a connector (8) for connecting to the end face of a thermoplastic resin outlet. ) Is provided at the tip of the control cord (9) extending from the main body case (2).

As shown in FIG. 3, the main body case (2)
Is a rectangular box-shaped hermetically sealed structure including a side plate (10) having a rectangular frame shape, a top plate (11) closing the upper surface of the side plate (10), and a bottom plate (12) closing the lower surface of the side plate (10). Aluminum, which prevents water from entering the inside of the main body case (2) in which various electric and electronic parts and wiring boards on which they are mounted are arranged, and which is excellent in heat dissipation of the bottom plate (12). And the like, and a large number of heat dissipation blades (13) are integrally formed on the lower surface side of the bottom plate (12), and the bottom plate (12) is used as a heat dissipation plate to suppress the temperature rise inside the main case (2). Protects various electric and electronic parts from heat, and attaches a power control element (14) or the like, which has a high temperature during operation, to the bottom plate (12) in close contact with the bracket (15) to obtain a high temperature rise suppressing effect. Is configured as

In FIG. 2, reference numeral (16) is a thermoplastic resin joint, and reference numeral (17) is the joint (16).
It is a tube made of the same material as the thermoplastic resin.

As shown in FIG. 4, the electric resistance wire (19) folded in two is formed on the inner peripheral surface of each receiving port (18) of the joint (16) into which the insertion port of the pipe (17) is inserted. Heating element (20) formed in a sleeve shape by spirally winding along
, Is embedded in advance by insert molding, and terminal pins (21) (21) attached to both ends of the electric resistance wire (19) are projected and fixed from the end faces of the respective receiving ports (18).

The electric resistance wire (19) is an electric resistance wire such as a nickel wire having an insulating coating formed of the same thermoplastic resin as that of the joint (16).

Further, between the terminal pins (21) and (21) on the end face of each of the receiving ports (18), a recess for product type discrimination having different depths depending on the product type, shape, size and the like of the joint (16). (22) is formed.

As shown in FIG. 5, fixed terminals (23) and (23) for inserting and connecting the terminal pins (21) and (21) are embedded in the connection end surface of the connector (8), and the fixed terminals (23) are also embedded. ) (23) through the recess (2
A movable terminal (25), which is a sensor arm having a tip portion inserted into 2), is slidably projected.

A potentiometer type sensor (26) is provided inside the connector (8),
A rack gear (28) that constantly meshes with the pinion gear (27) of the product type sensor (26) is formed on the movable terminal (25) inside the connector (8), and each terminal pin (21) (21) of the receiving port (18) and the connector. When the fixed terminals (23) and (23) of (8) are connected, the socket (1
The movable terminal (2) of the connector (8) is placed in the recess (22) of
5) is connected and the moving amount of the movable terminal (25) is detected by the product type sensor (26).
It is configured to determine the product type of 5).

A spring (29) for elastically pressing the movable terminal (25) in a protruding direction is connected to a mounting bracket (30) of the product type sensor (26) to regulate the protruding amount of the movable terminal (25). The movable terminal (25) is positioned at the reference position of the product type sensor (26) by the stopper (31).

In addition, the movable terminal (25) is formed in a cylindrical shaft shape, and a cylindrical shaft-shaped sensor case (32) is detachably inserted and fixed in the movable terminal (25). The temperature sensor (33), which is a thermistor, is attached to the tip of the movable terminal (2), and the tip of the temperature sensor (33) is exposed to the tip of the movable terminal (25).
5) is connected to the recess (22), the recess (2
2) The tip surface of the temperature sensor (33) is brought into contact with the bottom surface to detect the temperature (outside air temperature) of the joint (16) at the start of the electric fusion welding operation.

The control code (9) having the connector (8) attached at the tip is a power cord connected to the fixed terminals (23) and (23) and a product type signal transmission code connected to the product type sensor (26). And a temperature signal transmission cord connected to the temperature sensor (33) is connected to the CPU (34) provided in the controller (1).

As shown in FIG. 6, the controller (1)
And a CPU (34) comprising a microcomputer, and the CPU (34) is provided with the start button (3).
And a stop button (4) and the product type sensor (26)
A temperature sensor (33), the heating element (20), the display (5), and a memory (35) for storing a heat pattern are connected to each other, and a current is supplied to the heating element (20) based on the heat pattern. Of the pipe (17) is electrically fused to the receptacle (18) of the joint (16).

By the way, the memory (35) stores a heat pattern for each type of joint (16). As is apparent from the heat pattern diagram of FIG. 1, the heat pattern is a heating element (20). ) Electric resistance wire (1
9) shows the relationship between the current value (A) and the time (S) to flow in 9), and starts to flow the current from the start of the electric fusion welding work, and first increases the current value (A) to the first set current value (A1), The first set current value (A1) is maintained for the first time (S1).
Next, the current value (A) is increased to the second set current value (A2), and the second set current value (A2) is set for the second time (S).
2) Keep it. Next, the current value (A) is increased to the fifth set current value (A5) which is the maximum current value, and the fifth set current value (A5) is maintained for the third time (S3). Next, the current value (A) is decreased to the third current value (A3),
Current value (A3) is maintained for a fourth time (S4)
After the lapse of time (S4), the current supply is cut off.

The fourth current value (S4) is the current value for heating the thermoplastic resin, which is the molding material for the insulating film of the joint (16), the pipe (17) and the electric resistance wire (19), to this melting temperature. And the first to third set current values (A
1) (A2) (A3) to the fourth set current value (A4)
While setting it lower, the fifth set current value (A5) is set higher than the fourth set current value (A4), and A1 <A
2 <A3 <A4 <A5 is set, and a period from the start of the electric fusion welding operation to the elapse of the second set time (S2) is a drying step, and the heating element (2
0) to heat the surface of the resin to be melted by evaporating the moisture adhering to the inner peripheral surface of the receiving port (18) of the joint (16) and the outer peripheral surface of the pipe (17), and the above drying step. After completion, the process until the third set time (S3) elapses is a melting step, and the heat generation amount from the heating element (20) in this melting step is used to determine the inner peripheral surface of the receiving port (18) of the joint (16) and the pipe ( 17) The fixing process is performed until the outer peripheral surface of the outlet and the insulating coating of the electric resistance wire (19) are melted and the fourth set time (S4) elapses after the melting process is completed. The molten resin is gradually solidified in a stable state by the amount of heat generated from the heating element (20).

Then, as shown in FIG. 2, the controller (1) is brought into the piping site, and the plug (6) at the tip of the power cord (7) is connected to the power source such as a generator installed at the piping site. At the same time, the terminal pin (2) at the end face of the receiving port (18) of the joint (16) into which the insertion port of the pipe (17) is inserted.
After connecting the fixed terminals (23) and (23) and the movable terminal (25) of the connector (8) at the end of the control cord (9) of the controller (1) to the controller (1) (21) and the recess (22), By turning on the start button (3) of (1), the socket (1) of the joint (16) is
8) and the automatic control to automatically fuse the mouth of the pipe (17) is started. As shown in the heat pattern diagram of FIG. 1 and the flowchart of FIG. 7, the start button (3) is When turned on, first, the output values of the product type sensor (26) and the temperature sensor (33) are read, the product type of the joint (16) is determined based on the output values of the product type sensor (26), and the product type is selected. Heat pattern selection setting control (initial setting) of reading the corresponding heat pattern from the memory (35) is performed. After that, the drying control, the melting control, and the fixing control for controlling the current flowing through the heating element (20) are performed based on the heat pattern that is selectively set, and the electric fusion deposition is completed.

Further, as shown in the flow chart of FIG. 8, in the melting control, the output value (t
When a) is within the set range (for example, 10 ° C to 30 ° C), the heating element (2
The current supplied to 0) is controlled, but when the outside air temperature at the work site is high, the resin temperature rises quickly, and conversely, when the outside air temperature is low, the rise in the resin temperature slows down, so the temperature sensor (3
When the output value (ta) of 3) is higher than the set range, the third set time (S3) of the heat pattern is corresponding to the difference.
Is shortened, and conversely when it is low, the heat pattern is corrected so as to lengthen the third set time (S3) of the heat pattern corresponding to the difference, and thereafter, the heating element is corrected based on the corrected heat pattern. The current passed through (20) is controlled.

Further, the receptacle (18) of the joint (16)
If the insertion port of the pipe (17) is not properly inserted into the resin, the amount of heat transferred from the heating element (20) to the resin is small, the temperature of the heating element (20) rises quickly, and the temperature rises. Then, while the electrical resistance also increases, conversely, when the insertion is properly performed, the amount of heat transferred to the resin is large, and the temperature rise of the heating element (20) slows down. Then, the fact that the rising time of the current value flowing through the heating element (20) changes due to this characteristic is used to detect the defective insertion of the pipe (17), and it flows into the heating element (20) from the start of melting control. When the current value (Ax) rises to the set current value (A0) set lower than the fourth set current value (A4) of the heat pattern within the set time (S0), the pipe (17) is properly inserted. When the rising time exceeds the set time (S0) while the electric current is supplied to the heating element (20) and the electric fusion welding operation is performed, the pipe (1
7) is not inserted properly and the heating element (2
0) is relayed, and the indicator (5) indicates that the pipe (17) is not properly inserted, and the electric fusion welding process is interrupted before the resin is melted. )
Is prevented from being melt-adhered to the joint (16) in a poorly inserted state.

[0022]

As is apparent from the above embodiments, the present invention is directed to the receiving port (18) of the thermoplastic resin joint (16).
An electric fusion welding in which an electric current is supplied to a heating element (20) provided on an inner peripheral surface of the pipe (17) made of a thermoplastic resin to be fused to a receiving port (18) of the joint (16). In the device, the current value (A
When the time for which x) rises to the set current value (A0) exceeds the set time (S0), the outlet of the pipe (17) is not properly inserted into the socket (18) of the joint (16). It is provided with a defective insertion detecting means for the pipe (17) which judges that the defective insertion of the pipe (17) is detected by the detecting means, and the current supply to the heating element (20) is interrupted. It is possible to accurately detect the defective insertion of the pipe (17) that cannot be determined by the above method, and the fusion welding operation is interrupted when it is detected. It is possible to eliminate the failure of the above and always perform proper fusion welding.

[Brief description of drawings]

FIG. 1 is a heat pattern diagram.

FIG. 2 is an explanatory view of electric fusion welding work.

FIG. 3 is a sectional view of a controller.

FIG. 4 is a cross-sectional view of the receiving port of the joint.

FIG. 5 is a sectional view of the connector.

FIG. 6 is an electric fusion control circuit diagram.

FIG. 7 is a flowchart of the entire control.

FIG. 8 is a flowchart of melting control.

[Explanation of symbols]

 (1) Controller (16) Joint (17) Pipe (18) Receptacle (20) Heating element

Claims (1)

[Claims] 1. An electric fusion system in which an electric current is supplied to a heating element provided on an inner peripheral surface of a receiving end of a joint made of a thermoplastic resin to melt and attach an end of a pipe made of a thermoplastic resin to the receiving end of the joint. In the attachment device, when the time when the current value flowing through the heating element rises to the set current value exceeds the set time, it is determined that the pipe opening is not properly inserted into the receptacle of the joint. An electric fusion welding apparatus comprising: a defect detecting means, wherein when the detecting means detects a defective insertion of a tube, the supply of current to the heating element is interrupted.