JPS6133764A - Vapor phase soldering device - Google Patents

Abstract

PURPOSE:To prevent the leakage of vapor by opening a valve device to supply the cooling liquid in a tank to a sprayer to condense the vapor in a vapor vessel in a necessary case such as service interruption. CONSTITUTION:A solenoid valve 12 opens and the cold heat medium 2' stored in a liquid storage tank 10 is fed to a shower nozzle 11 and is sprayed into the vapor vessel 1 when the service interruption arises. The temp. in the vessel 1 is quickly decreased and the satd. vapor of the heat medium is condensed and liquified by such spraying, by which the volume is considerably decreased. As a result, the negative pressure below the atmospheric pressure is temporarily generated in the vessel 1 and the vapor of the heat medium remaining in the vessel 1 is stored in the vessel 1. The leakage of the heat medium vapor is thus prevented.

Description

[Detailed description of the invention]

[Field of Application of the Invention] The present invention relates to a steam soldering device that performs soldering using the latent heat of vaporization of steam, and particularly relates to an improvement for preventing leakage of steam during power outages. [Background of the Invention] Conventionally, a steam soldering device that performs soldering using the latent heat of vaporization of steam is disclosed in Japanese Patent Application Laid-Open No. 55-80 '395.
Batch-type soldering methods, such as those disclosed in ``Soldering Methods,'' were common. In such an apparatus, since the object to be soldered is immersed in the vapor phase of the heat medium confined in a sealed container and then soldered, accidents such as vapor leakage are less likely to occur. 1: On the other hand, in the case of in-line continuous steam soldering equipment that has come into use in recent years, accidents such as steam leaking from the steam tank during power outages are likely to occur. This will be explained below. In in-line continuous steam soldering equipment, in order to speed up the process, the items to be soldered are continuously carried in and out of the steam tank using a belt conveyor, so an open opening is provided in the steam tank. . Since it is necessary to immerse the object to be soldered in the saturated vapor phase of the heating medium, the height position of the open opening is determined so that steam is present above the position of the open opening. On the other hand, as a heating medium. Fluorinated solvents that are heavier than air, such as Fluorinert Fc>7°, sold by 3M, USA, are generally used. Therefore, if no measures are taken, the steam in the steam tank will leak to the outside through the open opening.However, the above-mentioned fluorinated solvents produce toxic byproducts (hydrofluoric acid) when heated. etc.) and is extremely dangerous if leaked. Second, conventionally, leakage of steam from the open opening has been prevented by providing a restorer, an exhaust device, etc. in the open opening. However, in the configuration of such a conventional device, there is a problem in that the restorer and the exhaust device operate normally in the event of a power outage or the like, otherwise steam would leak to the outside through the open opening. [Object of the Invention] Accordingly, an object of the present invention is to provide a steam soldering device that prevents steam leakage during power outages and the like. [Summary of the Invention] The present invention includes a tank for storing a cold liquid having the same composition as the steam in the steam tank, and a dispersion device connected to the tank via a valve device, which is installed in the steam tank. 7. When necessary, such as during a power outage, the valve device is opened to supply the cold liquid in the tank to the spraying device. By distributing cold liquid into the steam tank and forcing the steam inside the steam tank to return to its original position, the pressure inside the steam tank is made negative from the atmospheric pressure, thereby preventing steam leakage. [Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1st
In the figure, 1 is a steam tank, and a heater 3 is installed at the bottom of the tank.
is provided. Heat accumulated at the bottom of the steam tank! jL
2 is heated by the heater 3 and vaporized, and a saturated vapor phase 4 of the heating medium is formed inside the steam tank 1 . Side of steam tank 1

[
2 is an open opening 1 for carrying in and out the soldering object 8;
6 is provided, and through this open opening 16, the object to be hardened 8 is carried in by a conveyor 7, and after passing through the saturated vapor phase 4, it is carried out. In order to prevent the vapor of the heating medium from flowing out from the open opening 16, a restorer 6 consisting of a seed wire coil 5 is installed at the open opening.
and an exhaust duct 9 are provided. This is a pump for sending the heat medium 2 to the filter 14. A liquid storage tank 10 is provided above the steam tank 1, and the heat medium (liquid) discharged from the filter 14 is stored in this tank. 13 is a solenoid valve, and filter 14
The heat medium discharged from the steam tank 1 is returned to the steam tank 1 via a solenoid valve 13. A shower nozzle 11 is provided inside the upper part of the steam tank 1. A shower nozzle 11 is connected to a liquid storage tank 10 via a solenoid valve 12,
When this electromagnetic valve 12 is opened, the heat medium 2' stored in the liquid storage tank IO is supplied to the shower nozzle 11 and sprayed inside the steam tank 1. The solenoid valve 13 is controlled to be closed for a certain period of time from the time when the steam soldering apparatus is powered on, and then to be opened. Further, the solenoid valve 12 is controlled to be closed while the steam soldering apparatus is in operation, and is controlled to be opened when a power outage occurs. Next, the operation will be explained. When the steam soldering apparatus is powered on, the pump 15 is activated and the heat medium 2 in the steam tank 1 is sent to the filter 14. Since the solenoid valve 13 is closed for a certain period of time immediately after the power is turned on, the heat medium (liquid) that has passed through the filter 14 is sent to the liquid storage tank 10 and stored there. After a certain period of time, the solenoid valve 3 becomes open, so
The heating medium filtered by the filter 14 is as follows. It flows into the steam tank 1 located at a lower position than the liquid storage tank 10. Thus, during operation of the apparatus, the Φ heating medium 2 in the steam tank 1 is circulated through the filter 14. The heating medium is heated by two heaters 1 to form a saturated vapor phase 4 inside the steam tank 1 . The conveyor 7 is operated in a state where the saturated vapor phase 4 is formed. The objects 8 to be soldered are carried into the steam tank 1 through the open opening 16, heated by passing through the saturated steam phase 4, and then carried out through the open opening 16 after a certain period of time. In order to allow the object to be soldered 8 to pass through the saturated vapor phase 4, the open opening 6 is provided at a position lower than the saturated vapor phase 4. In addition, saturated steam as a heating medium has a higher specific gravity than air. A portion of the saturated vapor of the heating medium therefore flows out into the open opening 16. The saturated steam flowing out of 1: is seeded by the condensing coil 5 and liquefied, and the resulting heating medium returns to the steam tank 1 through the conduction pipe 17. A portion of the vapor that has not been liquefied by the condensing coil 5 is sucked together with air through the exhaust duct 9 and recovered in a recovery section (not shown in Figure 1). If a power outage occurs during such an operation, the condensing coil 5 and the exhaust duct 6 will stop operating, so there is a risk that the saturated steam of the heating medium in the steam tank 1 will flow out through the open opening 16. To prevent this, the solenoid valve 12 is opened and the cold heat medium 2' stored in the liquid storage tank 10 is opened.
is sent to the shower nozzle 11 and sprayed into the steam tank 1. As a result of this dispersion, the temperature inside the steam tank 1 rapidly decreases, and the saturated vapor of the heating medium is condensed into liquid, resulting in a significant volume increase.
decrease. As a result, the pressure inside the steam tank 1 becomes temporarily lower than the atmospheric pressure, and the steam of the heat medium remaining in the steam tank 1 is stored in the steam tank 1. In this way, leakage of heat medium vapor is prevented. Note that the amount of the heating medium 2' stored in the liquid storage tank 10 is determined according to the marked latent heat of the saturated vapor phase 4 and the amount of the heating medium 2 so as to achieve the above-mentioned effect. Also, the solenoid valve 13
The closed state time of is determined in consideration of the capacity of the pump 15 7 so that the required amount of heat medium is supplied to the liquid storage tank 10 . It is generally preferred that the heat medium is stored in the liquid storage tank 10 at a temperature of about IO"C or less. Although one embodiment has been described above in detail, the present invention is not limited thereto. For example, not only during a power outage, but also when an abnormality in the operation of the condensing coil 5 or exhaust duct 9 is detected, or when leakage of steam from the open opening 16 is detected, the solenoid valve is opened to release cold heat. The medium may be dispersed.Also, the device for dispersing the cold heat medium may be replaced with a means other than the shower or nozzle 11.Also, it is possible to use a means other than the shower or the nozzle 11. [ [Effects of the Invention] As is clear from the above description, 1. According to the present invention, leakage of heat medium vapor can be prevented during power outages, etc., safety of workers can be ensured, and the temperature in the steam tank can be rapidly lowered. Therefore, it is possible to achieve the effect of preventing thermal damage to objects to be soldered left inside the steam tank.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of a steam soldering apparatus according to an embodiment of the present invention. ■...Steam tank, 2...Heating medium, 3...Heater. 4... Saturated vapor phase, 5... Condensing coil, 6.
... Reconverter, 7... Conveyor, 8... Soldered object, 9... Exhaust duct, 10... Liquid storage tank, 11... Shower nozzle circulation 1.2.13.
...Solenoid valve, 14...filter, 15...pump.

Claims (1)

[Claims] (1) In a steam soldering device in which objects to be soldered are carried into and out of a steam tank containing steam by means of a conveying device via an open opening of the steam tank, It includes a tank for storing cold liquid, and a dispersion device provided inside the steam tank and connected to the tank via a valve device, and when necessary, opens the valve device to discharge the cold liquid in the tank. A steam soldering device, characterized in that the vapor soldering device is configured to supply water to the spraying device and spray it into the steam tank.