JP3049213B2 - Steam degreasing device and degreasing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam degreasing apparatus and a method for degreasing parts using an organic solvent vapor. Hereinafter, the above-mentioned vapor refers to the vapor of the organic solvent.

[0002]

The present invention is an extension of the prior art described below.

[0003] Trichloroethylene, which has a stricter regulation of solvent vapor emission than conventional 1.1.1-trichloroethane, has come to be used as an organic solvent for vapor degreasing. According to the steam degreasing apparatus using trichlorethylene, the vapor phase of the organic solvent is stabilized in the middle of the degreasing tank, and the parts to be cleaned (hereinafter, referred to as "work") are moved up and down in the degreasing tank, thereby degreasing. Since the cleaning of the work and the drying of the work in the tank are realized and the discharge of the organic solvent is suppressed, only about half the depth of the degreasing tank can be used for cleaning, and the effective range of degreasing is small. During the drying of the work, the vapor phase of the organic solvent is directly below the work, so the work is heated in the vapor phase and the cooling effect of the work is small, and in order to suppress the vapor leakage due to the vaporization effect of the organic solvent by the heat of the work, A long drying time is required. Since the height of the degreasing tank is twice as large as the effective size, which is the height of the degreasing tank when the work is kept at a fixed position, a deep equipment bit is required, and measures must be taken to ensure work safety. Become.

[0004] An object of the present invention is to provide a degreasing method and a steam degreasing apparatus capable of reducing the size of a degreasing tank and performing degreasing and drying of a component to be degreased even when the degreasing tank is low.

[0005]

According to a first aspect of the present invention, there is provided a steam degreasing apparatus which has a cooling pipe in the upper part of a degreasing tank and through which a refrigerant flows, and which cleans parts using organic solvent vapor. A degreasing tank having a space for accommodating and removing parts to be cleaned above the organic solvent, and a degreasing tank at the bottom of the degreasing tank .
Heating means of the solvent provided in the solvent, the air-degreasing bath
A steam degreasing apparatus comprising: a solvent vapor cooling unit provided at a bottom portion between the heating unit and a heating / cooling selection unit that selectively functions one of the heating unit and the cooling unit.

A second invention according to the present application is characterized in that a shutter is provided for selectively closing one of the heating means and the cooling means, which selectively communicates with a space through which a component to be degreased is put in and out. A steam degreasing apparatus according to the first aspect of the present invention.

A third invention according to the present application is the steam degreasing device according to the second invention, wherein the shutter is a slide shutter.

According to a fourth aspect of the present invention, the heating means and the cooling means are arranged such that the cooling means is located higher than the heating means.
There is an exposed side of the cooling means between the cooling means and the heating means, and the slide shutter closes the cooling means upper surface and the side exposed part and closes the heating means when the cooling means is closed. The steam degreasing apparatus according to the third invention is characterized in that, in the state, the upper part of the heating means is closed, but the side exposed part of the cooling means is opened.

A fifth invention according to the present application has a recovery device for an organic solvent gas generated in a degreasing tank, and this gas recovery device discharges gas from above a vapor phase boundary of the degreasing tank during cleaning of parts. The first feature is that the gas is sucked and collected and the gas is sucked and collected from the bottom side of the degreasing tank during the drying of the parts.
The steam degreasing apparatus according to any one of the first to fourth aspects of the present invention.

A sixth invention according to the present application is directed to a steam degreasing apparatus which has a cooling pipe through which a refrigerant passes above a degreasing tank and cleans parts by using an organic solvent vapor. A degreasing tank having a space for taking parts to be washed in and out, a heating means for a solvent provided in a solvent at the bottom of the degreasing tank, and a cooling means for solvent vapor provided at the bottom of the space of the degreasing tank, A steam degreasing apparatus, comprising: a shutter for selectively closing one of a side of a heating unit and a cooling unit that communicates with a space into and out of a component to be degreased.

A seventh invention according to the present application is the steam degreasing device according to the sixth invention, wherein the shutter is a slide shutter.

According to an eighth aspect of the present invention, the heating means and the cooling means are arranged such that the cooling means is positioned higher than the heating means,
There is an exposed side of the cooling means between the cooling means and the heating means, and the slide shutter closes the cooling means upper surface and the side exposed part and closes the heating means when the cooling means is closed. The steam degreasing apparatus according to the seventh aspect of the present invention, wherein, in the state, the position above the heating means is closed but the side exposed portion of the cooling means is opened.

A ninth invention according to the present application has a recovering device for an organic solvent gas generated in a degreasing tank, and this gas recovering device discharges gas from above a vapor phase boundary of the degreasing tank during cleaning of parts. The sixth feature is that the gas is suctioned and collected from the bottom side of the degreasing tank while the parts are being dried while the parts are being dried.
To the steam degreasing device according to any one of the eighth to eighth aspects.

According to a tenth aspect of the present invention, a degreasing tank having a heating means for an organic solvent and a cooling means for organic solvent vapor at the bottom of the tank and a degreasing tank having a cooling means at the top is used for degreasing in the degreasing tank. Parts to be disposed, the organic solvent is heated by heating means, an organic solvent vapor phase is generated so that the organic solvent vapor passes over the parts and reaches the upper cooling means, and the parts are degreased. A degreasing method characterized in that the organic solvent vapor is cooled from the bottom side of the tank using a cooling means, and the vapor phase boundary on the upper surface of the organic solvent vapor phase is set below the component to dry the component.

[0015]

2. Description of the Related Art Conventionally, components to which fats and oils have adhered have been degreased using an organic solvent vapor. In this degreasing, an organic solvent is contained in the bottom of the degreasing tank, and this organic solvent is vaporized by heating with a heating means, and the components are suspended in the vapor to degrease, and then the heating means is deenergized. Parts are raised to a high position in the degreasing tank and dried. Such a conventional example is disclosed in Japanese Patent Publication No. 57-43315,
There is a technique disclosed in JP-A-25087.

4 and 5 show a conventional example, in which a steam generating section 2 is provided at the bottom of a degreasing tank 1 and a degreasing effective zone K as shown in FIG.
The work W is suspended inside to perform degreasing, and the work W is pulled up above the vapor phase boundary U, as shown in FIG. The work W is dried while being sucked by the machine 6.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Overall Configuration) FIG. 1 is a longitudinal sectional view schematically showing an embodiment of the present invention. The degreasing tank 1 is in the form of a cylindrical container having an open top, and a steam generator 2 for generating organic solvent vapor and a bottom cooling unit 3 for cooling organic solvent vapor are juxtaposed at the bottom. Further, a slide shutter 4 for selectively closing the upper part of the bottom cooling part 3 and the steam generating part 2 is provided. A cooling pipe 5 is provided inside the upper portion of the degreasing tank 1 to prevent the overflow of the organic solvent vapor out of the tank. Then, the suction pipe 6a and the suction pipe 6a are introduced into the gas recovery machine 6 so that the organic solvent gas does not leak out of the tank.
6b (see FIGS. 1 and 2), and the suction pipe 6
Reference numerals a and 6b selectively suck the gas in the degreasing tank 1. The degreasing tank 1 is provided with an open-ended canopy 10 that opens and closes around a hinge 10a. The doors on both sides of the canopy 10 are closed, and a portion corresponding to the center of the degreasing tank 1 at a portion where the door ends coincide with each other has an opening 10b through which a wire 11 for suspending the work W can be inserted. It should be noted that the canopy 10 may be of a type that slides to both sides, and is similarly provided with an opening 10b.

(Steam Generation Unit) The steam generation unit 2 divides the bottom of the degreasing tank 1 into partitions 1a,
A space 1c is formed by the top plate 1b, and an organic solvent tank 2a is formed adjacent to the space 1c. Therefore, the organic solvent tank portion 2a is formed of the above-mentioned partition plate 1a and the plate material constituting the degreasing tank 1 and has a tank shape. An organic solvent S is stored in the organic solvent tank 2a. As the organic solvent S, for example, trichloroethylene is used. As a heating means for heating the organic solvent S to generate an organic solvent vapor, a heat exchanger passing through the primary side and having the organic solvent S as a secondary side is provided in the organic solvent tank section 2a. ing. The heat medium used for the heat exchanger 7 is, for example, high-temperature steam, and the supply of the high-temperature steam can be turned on and off by a control valve (not shown).

(Bottom Cooling Unit) A bottom cooling unit 3 is provided on the top plate 1b in the space 1c. The bottom cooling section 3 is provided with a heat exchanger 8 as a cooling means for cooling the organic solvent vapor and preventing the organic solvent S from generating the organic solvent vapor. The heat exchanger 8 passes through a cooling medium such as water to liquefy the organic solvent in the degreasing tank 1 and collects it in the organic solvent tank section 2a.
The organic solvent S is sent to the liquid surface of the organic solvent S therein to cool the organic solvent S, thereby stopping the generation of the organic solvent vapor in a short time.

(Slide Shutter) The slide shutter 4 is fitted to a guide rail (not shown) in the direction of the arrow a, and is movable in the horizontal direction to take a position to close the bottom cooling unit 3 and a position to cover the steam generation unit 2. be able to. One end of the upper plate 4a contacts the tank wall 1d on the side of the degreasing tank 1 near the heat exchanger 8 so that the slide shutter 4 closes the heat exchanger 8 of the bottom cooling unit 3. The lower edge of the side plate 4b hanging down from the other end of 4a is in contact with a member constituting the space 1c. Side plates 4 b according to Figure 1 are close or in contact with the corner portion of the partition plate 1a and the top plate 1b which constitute the space 1c. The slide shutter 4 is close to the front and rear side walls of the degreasing tank 1 before and after the sheet of FIG. 1, and the heat exchanger 8 is closed by the slide shutter 4 in the state of FIG.

(Cooling Pipe) The cooling pipe 5 approaches the inner wall of the upper part of the degreasing tank 1 and is disposed so as to be surrounded by a plan view, through which cooling water passes, and cools the rising organic solvent vapor. The organic solvent vapor is prevented from rising from the degreasing tank 1 and leaking out of the tank.

(Gas Recovery Machine) The gas recovery machine 6 has an upper limit vapor phase boundary U of the organic solvent vapor VS.
Alternatively, suction pipes 6a and 6b for sucking an organic solvent gas on the lowermost vapor phase boundary L are provided.
Is connected to the suction port of the exhaust blower so as to be switchable by a switching valve (not shown), and the discharge pipe of the exhaust blower communicates with the condenser to recover the organic solvent by the condenser.

When the steam degreasing device is stopped, no high-temperature steam is sent to the heat exchanger 7, and no cooling water flows to the heat exchanger 8. Then, the gas recovery unit 6 is not operated, and no cooling water flows in the cooling pipe 5.

The operation of the present invention will be described with reference to the work flowchart of FIG.

In step 1, the work W suspended by the transport means (not shown), for example, the wire 11 of the hoist, is carried above the degreasing tank 1 and stopped.

In step 2, the canopy 10 is opened.

In step 3, the workpiece W is lowered and stopped in the degreasing effective zone K in the degreasing tank 1 between the upper vapor phase boundary U and the slide shutter 4 shown in FIG.

In step 4, the canopy 10 is closed.

In step 5, when the organic solvent S is heated by passing high-temperature steam through the heat exchanger 7, the organic solvent S evaporates. At the same time, cooling water is flowed through the cooling pipe 5 and the gas recovery unit 6 operates. The gas recovery device 6 sucks gas from a suction pipe 6a opening at a lower position of the cooling pipe 5, but does not suck gas from a suction pipe 6b opening at the same height as just above the slide shutter 4.

The evaporated organic solvent vapor VS is cooled to the work W at normal temperature, liquefied on the surface of the work W, and the oils and fats adhering to the work W surface are washed away. Organic solvent vapor VS
Is cooled by the cooling water flowing through the cooling pipe 5 and liquefied and dropped in the cooling space 13 surrounded by the cooling pipe 5, and the organic solvent vapor in the cooling space 13 is reduced in concentration to the surrounding air. It becomes a mixed gas. This gas is sucked through the suction pipe 6a, and the organic solvent in this gas is recovered.

In step 6, the work W is dried without being moved. That is, the slide shutter 4 on the heat exchanger 8 through which the cooling water passes is moved rightward from FIG. 1 to open the upper part of the heat exchanger 8 and stop at a position covering the steam generator 2. In this state, an opening 12 is formed between the left edge of the slide shutter 4 and the top plate 1b.

Here, the cooling water is flowed into the heat exchanger 8 of the bottom cooling section 3 and the supply of high-temperature steam to the heat exchanger 7 of the steam generating section 2 is cut off. organic solvent vapor VS in is cooled and liquefied, the vapor phase boundary begins descending from the upper vapor phase boundary U. Further, the gas around the heat exchanger 8 cooled by the heat exchanger 8 of the bottom cooling unit 3 passes through the opening 12 as shown by an arrow c in FIG. The organic solvent S, which flows into the space 14 between the surface and the slide shutter 4 and is still high in temperature and is going to evaporate, is cooled and its evaporation is suppressed.

By the above operation, the vapor phase boundary rapidly decreases from the upper vapor phase boundary U shown in FIG. 1 to the lower vapor phase boundary L shown in FIG. 2, so that the drying of the work W is started immediately. Here, the suction pipe of the gas recovery machine 6 is switched to 6b. When the drying is completed, the process proceeds to step S7.

In step 7, the canopy 10 is opened.

In step 8, the work W is lifted by the hoist.

In step 9, the canopy 10 is closed.

As described above, in the present invention, the degreasing effective zone K is used as it is as a space for drying the work W by selectively operating the bottom cooling unit 3 and the steam generating unit 2. Need only be low. That is,
Since the heating means and the cooling means are arranged at the bottom of the degreasing tank and the heating means and the cooling means are selectively operated, degreasing and drying can be performed without moving the work W.

Since the heating means is a heat exchanger for passing a heat medium such as high-temperature steam, and the cooling means is a heat exchanger for flowing a cooling medium such as cooling water, the switching between heating and cooling of the organic solvent can be performed quickly. Since the cooling means and the heating means are juxtaposed in the horizontal direction, they act on the organic solvent without hindering each other. Therefore, even without the slide shutter 4, the heating / cooling selection unit applies a heating medium to a degreasing state in which the heating unit and the cooling unit are deactivated, and a heating medium in which the energizing unit is deactivated and the cooling unit is energized. As means for selecting the supply of the cooling medium, for example, a motor-operated valve may be provided in the pipes of the heat exchangers 7 and 8 to selectively open and close the motor-operated valve.

When a shutter for selectively closing one of the sides of the heating means and the cooling means, which communicates with the space for taking in and out the component to be degreased, is provided, the heat exchanger 7 of the heating means and the heat exchanger of the cooling means are provided. 8, it is possible to shorten the switching time of the heating of the organic solvent and the cooling action of the organic solvent vapor after the supply of the heat medium and the cooling medium is started and stopped. Further, while energizing both the heating means and the cooling means, either the heating or cooling function can be selected.

By using the slide shutter 4 as the above-described shutter, the height at which the shutter is closed is small, and the height of the degreasing tank 1 is slightly increased by installing the shutter. Further, the slide shutter 4 of the present embodiment selectively closes one of the upper portions of the heat exchangers 7 and 8 but completely opens the other, so that cleaning and maintenance and inspection of the inside are easy.

The heating means and the cooling means are such that the cooling means is located at a position higher than the heating means, there is an exposed side of the cooling means between the cooling means and the heating means, and the slide shutter is provided with a cooling means. In the closed state, the upper surface and the side exposed portion of the cooling unit are closed, and in the state where the heating unit is closed, the upper side of the heating unit is closed, but the side exposed portion of the cooling unit is opened. Thereby, especially when the cooling means is operated for cooling the organic solvent evaporation,
Since the cooling gas flows positively onto the liquid surface of the organic solvent, the speed of lowering the boundary of the vapor phase is increased and the preparation for the drying step is promptly performed.

The gas recovery machine sucks and recovers gas from above the vapor phase boundary of the degreasing tank during work cleaning, and suctions and recovers gas from the bottom side of the degreasing tank during work drying to thereby recover the work W. Since the concentration of the surrounding solvent vapor can be reduced quickly and the state can be maintained, the drying time does not become long.

[0044]

According to the present invention, the heating means of the organic solvent in the bottom of the degreasing bath, by which the selective heating means or cooling means provided with cooling means of the organic solvent vapor and operable, steam phase the boundary can be up and down, a component to be dry defatted large movement necessary to Without limiting the vertical, with Ino yo immobile, the degreasing bath can be lowered. Therefore, workability is good and the cost of the degreasing tank is low.

Since the supply of the heat medium to the heating means of the organic solvent is cut off, the drying efficiency is improved and the processing time can be shortened. Further, since the switching between the heating means and the cooling means can be performed quickly, the heat medium is supplied to the heating means immediately, and the degreasing step is started immediately.

As described above, since the height of the degreasing tank can be reduced, even if the degreasing tank is installed on the ground, it can be significantly reduced as compared with the conventional degreasing tank, so that the danger of working at heights can be reduced.
Moreover, the danger when the degreasing tank is provided as a bit underground can be reduced.

Since the cooling means is in the organic solvent vapor at the bottom of the degreasing tank and the vapor phase boundary of the organic solvent vapor is at a low position in the drying step, the reliability for suppressing the leakage of the organic solvent vapor is improved. Since a degreasing tank can be installed near a water tank used for washing with an adhesive when using an adhesive or for washing parts in a plating operation, the degree of freedom in installing a steam degreasing apparatus is increased.

When a pit is used, the construction cost is significantly reduced because the depth is greatly reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 3 is a work flowchart of the present invention.

FIG. 4 is a longitudinal sectional view of a conventional example.

FIG. 5 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

W: Work S: Organic solvent VS: Organic solvent vapor U: Vapor phase boundary L: Vapor phase boundary K: Degreasing effective zone 1: Degreasing tank 1a: Partition plate 1b: Top plate 1c: Space
1d: tank wall 2: steam generating section 2a: organic solvent tank section 3: bottom cooling section 4 ... slide shutter 4a ... top plate 4b ... side plate 5 ... cooling pipe 6 ... gas recovery machine 6a ... suction pipe 6b ... suction pipe 7 ... Heat exchanger 8 Heat exchanger 10 Canopy 10a Hinge 10b Opening 11 Wire 12 Opening 13 Cooling space 14 Space

Claims (10)

(57) [Claims] 1. A cooling pipe for passing a refrigerant to an upper part of a degreasing tank.
In a steam degreasing apparatus for cleaning parts using an organic solvent vapor, a degreasing tank containing an organic solvent and having a space for taking in and out parts to be cleaned above the organic solvent, and a solvent at the bottom of the degreasing tank A heating means for the solvent provided in the tank; a cooling means for the solvent vapor provided at the bottom of the space in the degreasing tank; and a heating and cooling selecting means for selectively operating any one of the heating means and the cooling means. A steam degreasing device, comprising: 2. A shutter according to claim 1, further comprising a shutter for selectively closing one of the heating means and the cooling means, which is in communication with a space through which a component to be degreased is put in and out.
A steam degreasing device according to item 1. 3. The steam degreasing device according to claim 2, wherein the shutter is a slide shutter. 4. The heating means and the cooling means, wherein the cooling means is located at a position higher than the heating means, and between the cooling means and the heating means, there is an exposed side of the cooling means. In the state where the cooling means is closed, the upper surface and the side exposed portion of the cooling means are closed, and in the state where the heating means is closed, the position above the heating means is closed but the exposed side part of the cooling means is opened. The steam degreasing apparatus according to claim 3, wherein: 5. A device for recovering an organic solvent gas generated in a degreasing tank, wherein the gas recovering device sucks and recovers gas from above a vapor phase boundary of the degreasing tank and cleans the component during component cleaning. 5. The steam degreasing apparatus according to claim 1, wherein the gas is suctioned and collected from a bottom side of the degreasing tank. 6. A steam degreasing apparatus which has a cooling pipe for passing a refrigerant at an upper part of a degreasing tank and cleans parts by using organic solvent vapor, wherein an organic solvent is accommodated and parts to be cleaned are taken in and out above the organic solvent. A degreasing tank having a space to perform, a heating means for the solvent provided in the solvent at the bottom of the degreasing tank, a cooling means for the solvent vapor provided at the bottom of the space of the degreasing tank, a degreasing of the heating means and the cooling means And a shutter for selectively closing any one of the sides communicating with the space for taking in and out the parts to be taken in and out. 7. The steam degreasing device according to claim 6, wherein the shutter is a slide shutter. 8. The heating means and the cooling means, wherein the cooling means is located at a position higher than the heating means, and between the cooling means and the heating means, there is an exposed side portion of the cooling means. In the state where the cooling means is closed, the upper surface and the side exposed portion of the cooling means are closed, and in the state where the heating means is closed, the position above the heating means is closed but the exposed side part of the cooling means is opened. The steam degreasing apparatus according to claim 7, wherein: 9. A device for recovering an organic solvent gas generated in a degreasing tank, wherein the gas recovering device sucks and recovers a gas from above a vapor phase boundary of the degreasing tank and cleans the component during component cleaning. The steam degreasing apparatus according to any one of claims 6 to 8, wherein the gas is suctioned and collected from the bottom side of the degreasing tank. 10. A component to be degreased is provided in a degreasing tank using a degreasing tank having a heating means for an organic solvent and a cooling means for an organic solvent vapor at a bottom of the tank, and a degreasing tank having a cooling means at an upper part thereof. The organic solvent is heated by the heating means to generate an organic solvent vapor phase so that the organic solvent vapor passes over the part and reaches the cooling means at the top, degreases the part, and uses the cooling means at the bottom of the tank to cool the bottom of the tank. A degreasing method, wherein the organic solvent vapor is cooled from the side, and the vapor phase boundary on the upper surface of the organic solvent vapor phase is set below the component to dry the component.