JP2001208612A - Thermometer for welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermometer for welding enabling a welding technician to easily control interpass temperature in welding. SOLUTION: This thermometer is made up of a permanent magnet 2 provided on a portable case 1 as an attaching means for putting the case 1 to attachment removably near a weld part 30, an infrared sensor 3 provided on the case 1 for outputting a signal on sensing infrared rays emitted from the weld part 30, a microprocessor provided in the case 1 and serving as an arithmetic processing means for converting the output signal from the infrared sensor 3 into temperature, a display 4 as a display means for displaying the temperature, and a buzzer serving as an alerting means for announcing that the temperature has fallen below a preset temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermometer for welding operation capable of controlling the temperature of a welded portion such as a steel frame member.

[0002]

2. Description of the Related Art Since the Great Hanshin Earthquake, the importance of heat input control and inter-pass temperature control of welded parts such as steel members has been highlighted.

[0003] In a steel structure building, the welded joint is the most important part, and if the strength and toughness are insufficient, the building may collapse in case of a large earthquake. Therefore,
It is necessary to perform welding under welding conditions that can ensure comprehensive mechanical performance, and to assure the quality of welding joints. These process controls cannot be managed by post-weld visual inspection and ultrasonic inspection to find physical defects, and new control methods are required.

Conventionally, inspection after welding has been performed based on steel frame accuracy inspection standards, but there is no effective inspection during welding, and the mechanical performance of welded joints varies in state and conditions. It is difficult to guarantee the mechanical performance of the weld joint after welding.

[0005] Since the earthquake, the relationship between welding conditions, welding heat input and interpass temperature, and tensile strength and impact value has been studied. At this time, the interpass temperature was measured using a high temperature thermocouple or resistance thermometer. Attempts have been made to measure with a thermometer.

[0006]

However, the conventional high-temperature thermometer is configured as a large-scale device of an installation type, or a portable type high-temperature thermometer is a device requiring a measurement operation, that is, a portable high-temperature thermometer is a device that requires an operator to perform a welding operation. Are not suitable for use by welding technicians at the time of welding to measure the interpass temperature and use it for the construction management. In particular, it was not possible for welding technicians at a construction site to carry and use them individually.

Therefore, an object of the present invention is to solve the above-mentioned problems, to be carried individually by a welding technician and to use the welding technician, so that the welding technician can easily manage the inter-pass temperature during welding. To provide a thermometer.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is provided on a portable case, mounting means for detachably mounting the case around a welded portion, and on the case. An infrared sensor that detects infrared rays emitted from a welded portion and outputs a signal, an arithmetic processing unit provided in the case, that converts an output signal of the infrared sensor into a temperature, and a display unit that displays the temperature And a notifying means for notifying that the temperature has fallen below the preset temperature.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment. Thermometer 10 for welding work of the present embodiment
Are basically provided on a portable case 1 and are provided on the case 1 with permanent magnets 2 as attachment means for detachably attaching the case 1 to the periphery of the welding portion 30, and are radiated from the welding portion 30. An infrared sensor 3 that senses infrared light and outputs a signal, a microprocessor provided in the case 1 and that is an arithmetic processing unit that converts an output signal of the infrared sensor 3 into a temperature, and a display unit that displays temperature. The display device 4 includes a display 4 and a buzzer which is a notification unit for notifying that the temperature has fallen below the preset temperature. The attachment means is not limited to the permanent magnet 2, but may be a steel member 2.
It can be temporarily fixed to 0 with a bolt.

FIG. 1 shows an external view of a thermometer 10 for welding work, and is a small heat-resistant case 1 which can be carried around.
Specifically, width 100mm x depth 60mm x height 40m
A case having a size of about m is provided. As shown in FIG. 2, a permanent magnet 2 is provided on the bottom surface of the case 1, so that the case 1 can be attached to the steel member 20 in the vicinity of the welded portion 30 by using its attraction force.

The case 1 has a welded portion 3 on its side.
An infrared sensor 3 that senses and measures infrared radiation emitted from 0 is provided, and a microprocessor (not shown) that converts a measurement signal from the infrared sensor 3 into a temperature is built in. Furthermore, the case 1 front (upper surface)
Has a digital display 4 for displaying the temperature converted as the temperature of the welded portion 30, and buttons 5a to 5e for various operations.
5c, and a buzzer (not shown) that emits sound when the measured temperature of the welded portion 30 falls below the preset temperature is provided inside the case 1.

In the illustrated example, the buttons 5a to 5c include a preset button 5a for presetting a temperature to be notified,
A release button 5b for releasing the preset and a stop button 5c for stopping the buzzer sound are provided. Here, for example, the preset button 5a can set one temperature value up to a maximum of 350 ° C.

The welding thermometer 10 is carried by an operator and, as shown in FIG. 2, a steel frame near the welded portion 30 utilizing the attraction force of the permanent magnet 2 fixed to the case 1. It is mounted on a horizontal or vertical surface of the member 20.
At that time, the case 1 is oriented so that the infrared sensor 3 faces the welded portion 30. The infrared sensor 3 is provided so as to protrude from the outer surface of the case 1 in the case of the present embodiment.
In such a manner that only its sensor surface is exposed on the case surface.

The inter-pass temperature of the welded portion 30 is indirectly measured by detecting infrared energy radiated from the welded portion 30 by the infrared sensor 3. That is, the microprocessor converts the measurement signal obtained from the infrared sensor 3 into a temperature, whereby the inter-path temperature is automatically measured and digitally displayed on the display 4. This measurement accuracy is
For example, it is preferable that the minimum weighing is about 2 ° C. and the error ± 1 ° C. The microprocessor can also manage the history record.

On the other hand, when the temperature falls below a preset temperature preset by the preset button 5a, for example, 400 ° C., a buzzer sounds to that effect. Therefore, the operator can perform the welding operation while controlling the inter-pass temperature of the welded portion 30 by working so as not to overlap the passes until such a buzzer sounds, and as a result, a high-quality welding can be performed. It can be performed.

FIGS. 3 to 5 exemplify temperature changes during welding. 3 shows the case where the temperature between passes is 200 ° C., FIG. 4 shows the case where the temperature between passes is 400 ° C., and FIG. 5 shows the case of continuous welding. The temperature between passes in the case of continuous welding is usually 450 ° C. to 650 ° C.

Incidentally, in order to correctly measure the temperature of the welded portion 30, it is necessary to correct the temperature indication of the thermometer 10 using the infrared sensor 3 accurately. The meter 10 is provided with a standard heating device (not shown), and the display value of the thermometer 10 can be finely adjusted and calibrated to the temperature display of the standard heating device in advance.

Further, the following correction function may be provided. That is, the amount and wavelength of infrared radiation emitted from the object to be measured not only varies depending on the material or surface condition thereof, but also varies depending on the temperature itself. The object that emits infrared rays most ideally is called a “perfect black body”, and this emissivity is defined as “1”. The infrared emissivity of an object is the ratio of the amount of infrared emissivity, and the emissivity of a perfect black body is defined as "1", so the emissivity of an actual object is always 1 or less. .

Therefore, in order to accurately measure the temperature of the welded portion 30, the emissivity of the welding thermometer 10 must be set to the value of the welded portion 3.
It is necessary to match the infrared emissivity from zero. That is, as shown in FIG. 6A, when the emissivity set in the thermometer 10 and the emissivity of the emissivity measurement object match, the thermometer 1
The display of 0 and the temperature of the object are in direct proportion. on the other hand,
When the emissivity set in the thermometer 10 does not match the emissivity of the object, as shown in FIG.
Between the displayed temperature and the actual temperature of the object.

In order to correct this deviation, in the thermometer 10 for welding work of the present embodiment, the emissivity set value is set to 0.95 in advance.
Alternatively, it can be switched to 0.7. This is executed by a microprocessor that converts an output signal from the infrared sensor 3 into a temperature.
Thus, the thermometer 10 for welding operation can be used with a set value closer to the emissivity of the welded portion 30 as the measurement object.

The thermometer 10 for welding work according to the embodiment described above.
According to this, the following operation and effect can be obtained. That is,
Since it is housed in the portable case 1, the welding operator can carry it with other tools. Permanent magnet 2
The welding operation can be carried out by a single welding operator because it is possible to cause the steel member 20 to be attracted to the steel frame member 20 and no temperature measurement operation is required. Since the temperature history can be recorded, management data can be left. Using the attached heating device, the indicated value of the thermometer 10 can be checked (when correct measurement fails, calibration can be performed). If necessary, the measured emissivity can be corrected by setting the microprocessor.

The thermometer 10 for welding work according to the present embodiment.
Has a maximum temperature of 700 ° C. to 800 ° C.
(Iron surface), radiant heat, magnetic field, impact, rainfall, dust, etc. can be used in harsh environments.

The thermometer 10 for welding work of the present embodiment can be used not only for welding work at a construction site but also for welding work in a factory.

In the above-described embodiment, an infrared sensor is used as a non-contact sensor. However, another type of non-contact sensor such as an optical sensor or a contact sensor such as a thermocouple is used. The thermometer 10 for welding work of the present invention can also be configured.

[0025]

As described above, according to the thermometer for welding work of the present invention, mounting means for being provided on a portable case for detachably mounting the case around the welded portion, An infrared sensor that is provided and senses infrared rays emitted from the welded portion and outputs a signal; an arithmetic processing unit that is provided in the case and converts the output signal of the infrared sensor into a temperature; and displays the temperature. Since the display means and the notifying means for notifying that the temperature has fallen below the preset temperature are provided, the welding operator can carry the tool together with other tools, and can be detachably installed, and Further, by relying on the notification of the notification means, direct measurement operation is not required, and the welding operator can appropriately perform welding management.

[Brief description of the drawings]

FIG. 1 is a front view of a thermometer for welding work of the present invention.

FIG. 2 is a diagram showing a use state of the thermometer for welding work of the present invention.

FIG. 3 is a diagram exemplifying a temperature change at the time of welding and showing a case where an inter-pass temperature is 200 ° C.

FIG. 4 is a diagram exemplifying a temperature change at the time of welding and showing a case where the inter-pass temperature is 400 ° C.

FIG. 5 is a diagram exemplifying a temperature change during welding and showing a case of continuous welding.

FIG. 6 is a diagram showing the display temperature indicated by the welding operation thermometer of the present invention and the actual temperature of the measurement object in relation to the infrared emissivity.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Case 2 Permanent magnet 3 Infrared sensor 4 Display 5a Preset button 10 Thermometer for welding work 20 Steel member 30 Welded part

Continuation of the front page (72) Inventor Yuzo Yamaguchi 3-47-8 Minami-Otsuka, Toshima-ku, Tokyo F-term (wide) 2G066 AB01 AC09 BA08 BC15 CB01

Claims (1)

[Claims] 1. A mounting means provided on a portable case for detachably mounting the case around a welded portion, and a signal output by sensing infrared rays radiated from the welded portion provided on the case. An infrared sensor, an arithmetic processing unit provided in the case, for converting the output signal of the infrared sensor into a temperature, a display unit for displaying the temperature, and a notification unit for notifying that the temperature has fallen below a preset temperature. And a thermometer for welding work.