WO2001019540A1

WO2001019540A1 - Method and device for washing article

Info

Publication number: WO2001019540A1
Application number: PCT/JP2000/006254
Authority: WO
Inventors: Toshiaki Amano; Masahiro Osakabe
Original assignee: Emhart Inc.
Priority date: 1999-09-13
Filing date: 2000-09-13
Publication date: 2001-03-22
Also published as: JP2001079503A; AU7311500A; JP3234204B2

Abstract

An article degreasing and washing method for washing those unwashed articles (26) such as small machine parts, capable of maintaining the considerations for environment without using any solvent such as trichloroethylene, preventing adverse effects of high temperature on those unwashed articles such as small machine parts and printed circuit boards, using a simple system configuration, and reducing a running cost, comprising the steps of feeding water into a closable steam generating container (2), heating water contained in the steam generating container (2) by a heater (13) and vacuating the steam generating container to a negative pressure by a vacuum pump (5) to generate low temperature steam, and feeding the low temperature steam into a washing container (3) storing and holding the unwashed articles (26) therein and decompressed to a negative pressure so as to inject the steam from nozzles (26), whereby the unwashed articles can be degreased and washed by steam flow.

Description

Description Method and apparatus for cleaning articles etc.

The present invention relates to a method and an apparatus for cleaning small mechanical parts such as rivets, electronic parts, and articles such as printed circuit boards, and more particularly to small mechanical parts, electronic parts and printed circuit boards without using a cleaning solvent such as trichloroethylene. The present invention relates to a method and an apparatus for degrease and cleaning an object to be cleaned such as a substrate. Background art

Japanese Patent Application Laid-Open No. 3-127673 discloses that an object to be cleaned of an electronic component printed circuit board is arranged in a flow of superheated steam, and that the object to be cleaned is contaminated by the flow of superheated steam. Methods for removal are described. Since this method uses superheated steam without using a chlorine-based organic solvent such as trichloroethylene, it has an advantage that pollution can be prevented.

However, the cleaning method described in the above-mentioned Japanese Patent Application Laid-Open No. 3-127673 removes dirt on the object to be cleaned by the flow of superheated steam, so that the boiler, the superheater, the condenser, etc. Required, complicating the configuration of the entire system, and increasing the running cost of the system. In addition, since superheated steam is used, electronic components and printed circuit boards to be cleaned may be heated to high temperatures and may be affected. Disclosure of the invention

Therefore, an object of the present invention is to maintain environmental considerations without using a solvent such as trichloroethylene, and to prevent adverse effects of high temperature on small articles such as small mechanical parts, electronic parts, printed circuit boards, etc. An object of the present invention is to provide a degreasing and cleaning method and apparatus with a low running cost of the system configuration.

In the method for cleaning an article or the like to be cleaned according to the present invention, water is supplied to a sealable steam generation container, the water in the steam generation container is heated, and the steam generation container is set to a negative pressure to generate low-temperature steam. And supplying steam to the cleaning container in which the object to be cleaned is housed and held and jetted into a negative pressure cleaning container, and degreases and cleans the object to be cleaned by the steam flow. I do.

As a result, the washing is carried out with steam such as tap water, so that environmental considerations are maintained without using solvents such as trichloroethylene, and steam is generated under negative pressure. Is a low temperature of, for example, about 60 ° C., and the object to be cleaned is not heated to a high temperature. In the above-mentioned cleaning method, it is preferable that the method further includes a step of maintaining the negative pressure in the cleaning container after the stop of the ejection of the steam into the cleaning container, or a step of heating the object to be cleaned. Thus, the object to be cleaned after the cleaning can be dried.

An apparatus for cleaning an article or the like to be cleaned according to the present invention includes: a steam generation container connected to a water supply pipe; a vacuum pump for setting the steam generation container to a negative pressure; and heating water in the negative pressure steam generation container. Heating means for generating low-temperature steam by heating, a cleaning container for accommodating the object to be cleaned, a vacuum pump for applying a negative pressure to the cleaning container, and a supply of steam in the steam generation container to the cleaning container. And means for degrease and cleaning the object to be cleaned by the flow of the steam.

As described above, the cleaning device according to the present invention requires a boiler, a superheater, a condenser, and the like. Therefore, the configuration of the entire system becomes extremely simple, and the running cost of the system can be kept low. In the above-mentioned cleaning apparatus, a cleaning tank capable of accommodating a plurality of cleaning containers is included, and a means for heating the cleaning container is provided around the plurality of cleaning containers contained in the cleaning tank. Preferably, they are arranged. Further, the vacuum pump for making the steam generation container a negative pressure and the vacuum pump for making the cleaning container a negative pressure are the same vacuum pump, and the vacuum pump is connected to the cleaning tank to make the cleaning tank a negative pressure. It is preferable that the pressure of the washing container accommodated therein is reduced. Alternatively, the vacuum pump and the steam generation container may be directly connected to make the steam generation container have a negative pressure.

Further, according to the present invention, there is provided a method of cleaning an object to be cleaned such as an article, wherein the step of disposing the object to be cleaned in a sealable cleaning container and applying a negative pressure to the cleaning container includes the steps of: A step of injecting hot water into a pressure washing container to generate low-temperature steam, exposing the object to be washed to the flow of steam, and degrease and washing the object to be washed with the steam. Provided. According to this method, the environment is maintained without using a solvent such as ethylene, etc., and the steam is heated under negative pressure, so the temperature of the steam is low and the object to be cleaned is heated to a high temperature. In addition to the advantage that no steam is generated, the low-temperature steam is generated in the cleaning vessel without using a steam generating vessel, so that it is not necessary to supply steam to the cleaning vessel. In this cleaning method, it is preferable to suck the vapor flow passing through the cleaning object from the cleaning container to the outside.

Further, according to the present invention, there is provided an apparatus for cleaning an object to be cleaned such as an article, wherein the apparatus includes a sealable cleaning container capable of storing and arranging the object to be cleaned, a vacuum pump for applying a negative pressure to the cleaning container, and a cleaning container. A hot water injection means for injecting hot water into one end to generate low-temperature steam in the negative pressure washing container; and Means for sucking steam to the outside so as to perform degreasing cleaning through the object to be cleaned. According to this device, a boiler, a superheater, a condenser, and the like are not required, and a steam generation vessel and a system for supplying steam are not required. Therefore, the configuration of the entire system is further simplified, and The running cost can be further reduced. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram of a cleaning apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a cleaning device according to a second embodiment of the present invention.

FIG. 3 is a block diagram of a cleaning device according to a third embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a cleaning apparatus 1 according to a first embodiment of the present invention. The cleaning apparatus 1 includes a steam generation container 2 serving as a sealable vacuum container, a cleaning tank 3 forming a sealable cleaning chamber, and a vacuum pump 5 for maintaining the inside thereof at a negative pressure. The washing tank 3 can accommodate a plurality of washing containers 6 for accommodating small mechanical parts such as rivets. The vacuum pump 5 for evacuating the steam generation container 2 and the cleaning tank 3 may be shared by a single pump as shown in the figure, and the steam generation container 2 and the cleaning tank 3 may be separately evacuated. You may have two. Further, the reason why the pressure in the cleaning tank 3 is set to be negative is to maintain the pressure in each of the cleaning vessels 6 at a negative pressure. Therefore, instead of the vacuum pump 5, a vacuum pump for individually vacuuming each of the cleaning vessels 6 is used. It can also be provided.

The steam generation vessel 2 has a line 11 from a water supply source such as water supply via a valve 10. It is connected so that water is supplied to the steam generation vessel 2. On the bottom of the steam generating container 2, a heater 13 as a heating means for heating the supplied water is arranged. The power supply 13 is turned on and off by an external power supply 14. Further, a line 15 extends from the upper part of the steam generation vessel 2, and the line 15 passes through a valve 17 to the upper end of the cleaning vessel 6 arranged in the cleaning tank 3, and is connected to the steam generation vessel 2. The generated steam is sent to the cleaning vessel 6. In the steam generation vessel 2, since a negative pressure can be maintained, steam having a temperature lower than 100 ° C. is obtained. Normally, it boils sufficiently at 50 ° C when the degree of vacuum is around 65 mmHg. The low-temperature steam may be generated by heating the water in the steam generation container 2 by heating the water in the steam generation container 2 while maintaining the inside of the steam generation container 2 at a predetermined negative pressure. (20 ° C. to 80 ° C., preferably 60 ° C.), the pressure in the container may be reduced to a negative pressure, and the heating and vacuum suction may be performed simultaneously. Good. Although not shown, it is preferable to provide a sensor or the like in order to know the temperature and pressure inside the steam generation container 2.

The cleaning tank 3 is connected to a line 18 from the vacuum pump 5 through a valve 18 to make the cleaning tank 3 a negative pressure. A pressure gauge 21 may be provided in the middle of the line 18 to monitor the pressure of the washing tank. On the bottom surface of the washing tank 2, a drain line 22 for discharging moisture caused by steam passing through the washing vessel 6 is provided. Further, a heater 23 is provided as a heating means for heating the washing container 6 from outside. The heater 23 is for removing (evaporating) water from the object to be washed in the washing container 6. Since the washing container 6 is maintained at a negative pressure, its moisture can evaporate at a low temperature, so that the temperature of the heater 23 does not need to be increased.

Each washing vessel 6 is connected to a line 15 from the steam producing vessel 2 at the upper end. A low-temperature steam is supplied to the cleaning container 6. This steam is supplied so as to jet to the cleaning vessel 6. Except for the upper end and the lower end of the cleaning container 6, a large amount of objects 26 to be cleaned such as rivets are stored. The lower end of the cleaning vessel 6 communicates with a cleaning chamber formed inside the cleaning tank 3, and the cleaning chamber is under a negative pressure by the vacuum pump 5. Through to the lower end. The steam flow removes dirt (especially oily dirt) from the object to be cleaned and performs degreasing cleaning. The method of holding the object 26 to be cleaned may be arbitrary, but it is preferable that the vapor is easy to flow while maintaining the speed, and the vapor is preferably held so as to contact the surface of each object to be cleaned as much as possible. .

The shape of the washing container 6 is such that, for example, for a holed component such as a rivet or other mechanical component or an electronic component, or for an article having a complicated shape, the steam is easy to flow in a state where the speed is maintained. It may be of such a degree as to regulate as much as possible to contact the surface, for example, it can be formed in a cylindrical shape. However, if it is a plate-shaped member such as a printed circuit board, it is formed in a box shape that can accommodate it. In addition, the effect of cleaning cannot be obtained unless steam is applied two-dimensionally to the surface of the printed circuit board. Therefore, a large number of linear nozzles (connected to the line 15) are arranged in two rows in the box-shaped washing container so as to face each other. If the plate-like member passes between the two rows of nozzle groups, the vapor from each nozzle flows along the surface of the plate-like member, and it becomes possible to remove dirt on the surface. Further, in the case of cleaning such plate-like members, the cleaning container may be eliminated, the plate-like members may be held in the cleaning tank 3, and two rows of nozzle groups may be provided to perform surface cleaning. Good.

Next, the operation of cleaning small mechanical parts using the cleaning apparatus 1 having the above configuration will be described. Water is supplied from a water supply source such as water supply to the steam generation vessel 2 through the line 11. Next, the temperature was set to 20 ° C to 80 ° C (13 ° C in the experimental example. At the same time, the water is heated, and the vacuum pump 5 is operated to open the valve 17 to maintain the steam generation vessel 2 at a negative pressure through the line 15. As a result, low-temperature steam is generated, and is supplied to each cleaning container 6 of the cleaning tank 2 through the line 15 by opening the valve 17. From a nozzle 25 at the tip of a line 15 provided at the upper end of each washing vessel 6, low-temperature steam is blown into the washing vessel. The cleaning container 6 is filled with dirty small machine parts which are to be cleaned 26. On the other hand, since the vacuum in the cleaning chamber of the cleaning tank 3 is reduced by the vacuum pump 5, the steam flows at a high speed in the cleaning vessel, and the dirty small machine parts (the cleaning object 26) are degreased and cleaned. . After the cleaning is completed, the small machine parts to be cleaned 26 are wet due to the temperature difference between the steam and the parts.The steam supply is cut off, and the vacuum pump 5 is operated as it is to maintain the negative pressure in the cleaning vessel. By turning on the heater 23, the temperature of the object 26 is raised (about 80 ° C.). As a result, the residual moisture of the object 26 was completely evaporated. Therefore, there is no need to install a separate drying device.

In the cleaning of a printed circuit board (plate-like member), as described above, a large number of linear nozzles are arranged in two rows in the cleaning chamber so as to face each other, and the plate-like member as an object to be cleaned is passed between the nozzles. As a result, dirt on both sides of the plate member is removed along the surface. After the cleaning is completed, the steam supply is cut off, the negative pressure in the cleaning chamber containing the plate-like member to be cleaned is maintained, and the plate-like member is warmed by heating 23 to completely remove the adhering moisture. Evaporates, making drying equipment unnecessary.

In general, it is considered that when high-temperature steam is sprayed onto a machine part to which oil has adhered, the oil component evaporates due to the heat energy of the steam, and then the oil component is carried away by the flow velocity. However, according to the experiments performed by the inventors of the present application, a degreasing effect was obtained even with low-temperature steam. Therefore, the degreasing cleaning is considered to be due to mechanical (physical) scraping by flow velocity rather than evaporation effect by high temperature. Also, steam flows It was also found that by restricting the direction, it was possible to efficiently clean the inside of the hole of the part. Furthermore, in the case of cleaning internal parts with holes such as rivets, if the parts are filled in a container that regulates the direction of steam flow, and the container is placed in a vacuum, it is possible to use the method described in Japanese Patent Application Laid-Open No. HEI 3-127676. Experiments confirmed that the same effect as that obtained by using superheated steam described in Japanese Patent Publication No. 3 was obtained. A feature of low-temperature steam cleaning is that it can have no or negligible effect of thermal strain on the object to be cleaned. Therefore, it is suitable for cleaning not only small mechanical parts but also electronic parts and printed circuit boards. In particular, the energy efficiency of the low-temperature steam generator is much higher than that of the superheated steam generator described in JP-A-3-127673, the number of parts constituting the system is small, and the water used is small. It is easy to manage and the whole system is economical.

In the plate member cleaning experiment, the machine sludge, carbonized machine oil, and fibrous dirt were cleanly cleaned with a 1-minute jet. In a rivet washing experiment, rivets were filled in a cylindrical washing container for regulating the flow of steam, and the washing container was set in a washing room. After one minute of steam injection, the valve was closed and the cleaning chamber was evacuated for about one minute. As a result, the inside of the rivet body was completely degreased. FIG. 2 shows a cleaning apparatus 30 according to a second embodiment of the present invention. In this embodiment, no steam generation vessel is provided. The cleaning device 30 includes a sealable cleaning container 31 for accommodating an object to be cleaned 26 such as small mechanical parts, a vacuum pump 33 for applying a negative pressure to the cleaning container, and a cleaning container via a valve 34. 3 A line 35 supplying hot water to one end of 1 and a nozzle 3 provided at the end of the line 35 for injecting hot water so as to generate low-temperature steam in a negative pressure washing vessel. The vacuum pump 33 is provided with a valve 38 and a separator 39 at the other end of the cleaning vessel 31 so that a low-temperature steam flow is sucked outside through the workpiece 26. And line 41. The separator 39 is attached to the steam flow and the object to be cleaned. Water from the exhaust steam stream.

The operation of the cleaning device 30 according to the second embodiment will be described. The washing container is filled with an object 26 to be washed such as a rivet, and the vacuum is increased by a vacuum pump 33 to maintain a negative pressure. Open valve 34 and supply hot water to nozzle 37 through line 35. Spray warm water from nozzle 37 into mist. Since the inside of the cleaning vessel 31 is maintained at a negative pressure, the hot water vaporizes and expands to generate steam, and the steam flows through the packed bed of the object 26 to be cleaned, and is covered by the steam. The cleaning material 26 is degreased and cleaned. After washing, close the warm water valve 34 and operate the vacuum pump 33 as it is to keep the inside of the washing container at a vacuum and evaporate residual moisture. If necessary, the temperature of the object 26 to be cleaned can be increased by an external heater (not shown) or the like, so that the evaporation can be made faster.

FIG. 3 shows a cleaning device 45 according to a third embodiment of the present invention. In this embodiment, a plurality of cleaning containers 47 similar to the cleaning container 31 of the cleaning device of the second embodiment are housed in a cleaning tank 46 similar to the cleaning tank of the cleaning device of the first embodiment. Has been done. In the cleaning device 45, each of the cleaning containers 47, which can accommodate and place the objects to be cleaned 26 such as small mechanical parts, is opened at the outlet portion 49 toward the cleaning tank 46, and the low-temperature steam is released. It is designed to be discharged into the washing tank. Further, a vacuum pump 50 is provided in the cleaning tank 46 to maintain the inside of the cleaning tank at a negative pressure. Further, the washing tank 46 is provided with a valve 51 and a drain line 53, through which moisture caused by steam passing through the washing container 47 is discharged. Hot water is supplied from a common supply line 54 to a selected washing vessel 47 via a valve 55 and a nozzle 57 provided at the inlet side of each washing vessel 47, and the hot water is supplied to the selected washing vessel 47. Produces low-temperature steam. A heater 58 is provided around the outer periphery of the plurality of cleaning containers 47 to heat the respective cleaning containers 47 from the outside. Remove (evaporate). Since each cleaning vessel 6 is maintained at a negative pressure in the cleaning tank, its water content can evaporate at a low temperature, and the temperature of the heater 46 does not need to be raised.

The operation of the cleaning device 45 according to the third embodiment will be described. Each washing container 47 is filled with an object 26 to be washed such as a small mechanical part, and a vacuum pump 50 is used to increase the degree of vacuum in the washing tank to maintain a negative pressure. The selected valve 55 is opened, and the hot water from the line 54 is sprayed from the corresponding nozzle 57 into the washing container 47 in the form of a mist. Since the outlet portion 49 of each cleaning vessel 47 is opened to the negative pressure cleaning tank 46 and maintained at a negative pressure, the hot water is vaporized and expanded to generate steam, and the steam flow is reduced. The object to be cleaned 26 is degreased and washed by flowing through the packed layer of the object to be cleaned 26 and the vapor flow. After the washing is completed, the valve 55 is closed to stop the supply of hot water, the vacuum pump 50 is operated as it is, the inside of the washing tank 46 is maintained at a negative pressure, and residual moisture is evaporated. In this case, the temperature of the object 26 to be cleaned can be increased by heating the air 58 so that the evaporation can be made faster. Since the pressure in the washing tank is maintained at a negative pressure, the water can evaporate at a low temperature, and the temperature of the heater 46 does not need to be raised. Industrial applicability

According to the present invention, since the washing is performed with steam such as tap water, consideration for the environment is maintained without using a solvent such as tricloethylene, and the steam is evaporated under a negative pressure. The temperature is low, and the object to be cleaned is not heated to a high temperature and has no thermal distortion. Since the cleaning device according to the present invention does not require a boiler, a superheater, a condenser, or the like, the configuration of the entire system is extremely simplified, and the running cost of the system can be reduced. According to another aspect of the present invention, in addition to the above advantages, the generation of low-temperature steam can be performed without using a steam generation vessel. The cleaning is performed in the cleaning vessel, eliminating the need to supply steam to the cleaning vessel. Furthermore, in addition to eliminating the need for boilers, superheaters, condensers, etc., the need for a steam generation vessel and a steam supply system is also eliminated, which further simplifies the configuration of the entire system and reduces system running costs. It can be further reduced.

The present invention may be embodied in various other forms without departing from its spirit or essential characteristics. Therefore, the above-described embodiment is merely an example in every respect and should not be construed as limiting. The scope of the present invention is defined by the appended claims, and is not restricted by the specification text. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

Claims

The scope of the claims

1. A method of cleaning an object to be cleaned, such as an article,

Supplying water to a sealable steam generation container, heating the water in the steam generation container, and generating a low-temperature steam by reducing the pressure of the steam generation container to a negative pressure;

A step of supplying the steam so as to be ejected into a cleaning container in which the object to be washed is held and held and having a negative pressure, and degreases and cleans the object to be washed by the steam flow. How to wash.

2. The cleaning method according to claim 1, further comprising a step of maintaining a negative pressure in the cleaning container after stopping the ejection of steam into the cleaning container.

3. The cleaning method according to claim 1 or 2, further comprising a step of heating the object to be cleaned after stopping the ejection of steam into the cleaning container.

4. In an apparatus for cleaning an article or the like,

A steam generation vessel to which the water supply pipe is connected,

A vacuum pump for applying a negative pressure to the steam generation vessel;

Heating means for heating water in the negative-pressure steam generation container to generate low-temperature steam; a cleaning container for accommodating the object to be cleaned;

A vacuum pump for applying a negative pressure to the washing container;

Means for supplying the steam in the steam generation container so as to be jetted to the cleaning container and degrease and wash the object to be cleaned by the flow of the steam; A cleaning device comprising:

5. The cleaning apparatus according to claim 4, further comprising a cleaning tank capable of storing a plurality of the cleaning containers.

6. The cleaning device according to claim 5, wherein a means for heating the cleaning container is arranged around an outer periphery of the plurality of cleaning containers housed in the cleaning tank.

7. The cleaning apparatus according to claim 5, wherein the vacuum pump that makes the vapor generation container have a negative pressure and the vacuum pump that makes the cleaning container have a negative pressure are the same vacuum pump; A cleaning device connected to the cleaning tank to reduce the pressure of the cleaning tank to a negative pressure of the stored cleaning container.

8. A method for cleaning an object to be cleaned, such as an article,

Disposing an object to be cleaned in a sealable cleaning container, and applying a negative pressure to the cleaning container;

A step of injecting hot water into the negative pressure cleaning container to generate low-temperature steam, exposing the object to be cleaned to the flow of steam, and degrease and cleaning the object to be cleaned with the steam;

A cleaning method comprising:

9. The cleaning method according to claim 8, wherein a steam flow passing through the cleaning object is sucked to the outside from a cleaning container.

10. An apparatus for cleaning an article or the like to be cleaned,

A sealable washing container capable of containing and arranging an object to be washed;

A vacuum pump for applying a negative pressure to the washing container,

Hot water jetting means for jetting hot water to one end of the washing container to generate low-temperature steam in the negative pressure washing container,

The vacuum pump is connected to the other end of the cleaning container so that the steam flow is sucked to the outside through the object to be cleaned.

A washing device characterized by the above-mentioned.