JP2935089B2 - Precision cleaning method for machine parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for precision cleaning of mechanical parts and the like, in which a large number of objects to be cleaned such as mechanical parts and electronic equipment parts are put into a cleaning basket, and the objects to be cleaned are precisely cleaned in basket units.

[0002]

2. Description of the Related Art Conventionally, precision cleaning of mechanical parts, electronic equipment parts and the like has been performed simply and efficiently using a chlorinated solvent such as chlorofluorocarbon or trichloroethane. However, this kind of solvent was considered to be the cause of ozone depletion, and it was urgently required to completely eliminate it. Numerous alternative cleaning methods have been proposed and implemented by trial and error. Despite this situation, the use of solvents that are convenient but whose safety has not been confirmed, and the use of hydrocarbon solvents that cause global warming without destroying the ozone layer should be avoided. . That point,
Although water-based cleaning agents require proper treatment of wastewater, they are highly safe and are expected to be widely used in the future. Among them, the application fields that can be washed only with high-temperature pure water are quite wide, and the wastewater treatment and recovery / reuse are easy. Therefore, it is considered that they will be widely applied to precision washing in the future.

In the case of such cleaning using only water or using a water-based cleaning agent, the action of physical force on the surface of the object to be cleaned is very important in order to efficiently perform high-precision cleaning. is there. Conventionally used physical forces include the collision of spray droplets (colliding the droplets of the spray with the surface of the object to be cleaned and removing dirt by the force of the collision), and the action of ultrasonic waves in the liquid (ultrasonic). The action of sound waves promotes the dispersion and dissolution of dirt, etc.), and the blowing of bubbles (produces a myriad of small bubbles in the liquid and promotes cleaning by contacting the bubbles with the object to be cleaned and stirring the liquid); Turbulence by a submerged jet (making a strong turbulence in the liquid and agitating the liquid with its power).

On the other hand, in the cleaning of mechanical parts and the like performed in actual production sites and the like, a large number of objects to be cleaned are put in a cleaning basket in order to efficiently clean various parts produced in large quantities. Very often washed.

FIG. 4 shows an example of an ultrasonic cleaning method, and FIG. 5 shows an example of a spray cleaning method.

In the ultrasonic cleaning method, a cleaning basket (32) containing an object to be cleaned (A) is immersed in a cleaning liquid in a cleaning tank (31), and the cleaning liquid is circulated. The ultrasonic vibrator (33) arranged in the above is vibrated to generate ultrasonic waves, and the action of the ultrasonic waves promotes the dispersion and dissolution of dirt.

In the spray cleaning method, a cleaning basket (42) containing an object to be cleaned (A) is suspended in a cleaning tank (41), and the cleaning basket (4) is suspended.
The cleaning liquid is sprayed onto the 2) from above and around by a spray (43), and the droplets of the spray (43) collide with the surface of the object (A) to be cleaned, and the dirt is removed by the force of the collision.

In any of the above ultrasonic cleaning and spray cleaning, it is difficult to sufficiently exert physical force on the object to be cleaned placed at the center of the basket. For this reason, auxiliary means for enhancing the detergency are often used together. The auxiliary means includes vertical swinging (eliminating unevenness of washing caused by ultrasonic washing, etc.), horizontal swinging (rotating the washing basket horizontally to make spray and ultrasonic action uniform, and centrifugal force ( Rotate the washing basket in the liquid at high speed to increase the frictional force with the surrounding liquid to promote washing), rotate (the basket with hexagonal or octagonal cross section is rotated around the horizontal axis, (So that spray or ultrasonic waves can be easily applied to the remaining surface), vibration (shake the washing basket several tens of times or more per minute, and enhance the relative movement between the liquid and the object to be washed to promote washing). is there.

FIG. 6 shows an example of a conventional metal parts cleaning system configured by combining the above-described cleaning method and auxiliary means. In the example shown in the figure, a spray cleaning method is used in the preliminary cleaning, an ultrasonic cleaning method is used in the main cleaning, and an ultrasonic cleaning method is used in the rinsing (finish cleaning). In addition to spray cleaning and ultrasonic cleaning, a submerged jet system or bubble system may be used.

[0010]

As described above, it has often been difficult to perform good cleaning uniformly over the entire number of parts in a cleaning basket even when various physical forces are used. Therefore, in order to enhance the cleaning effect without excessively complicating the apparatus, the shape of the object to be cleaned,
While taking into account the amount to be treated in one basket, the nature of the stains attached, etc., various tests are performed to determine the optimal combination of the above-mentioned physical force and cleaning power enhancement auxiliary means. When the shape of the object to be cleaned is very complicated, a great deal of testing is required to find conditions that can sufficiently clean all the objects to be cleaned in the basket.

For this reason, it is important to provide an effective cleaning power enhancing method when cleaning a large number of components with a cleaning basket.

In the case of cleaning using only water or a water-based cleaning agent, it is necessary to pay special attention to drying of water adhered after cleaning, and there is a problem that it takes time to dry.

An object of the present invention is to provide a precision cleaning method for machine parts and the like which efficiently cleans a large number of small parts having a complicated shape, which are put in a cleaning basket, with pure water or an aqueous cleaning agent. is there.

Another object of the present invention is to provide a machine which efficiently cleans a large number of small-sized parts and the like placed in a cleaning basket with pure water or a water-based cleaning agent, and efficiently drains and dries. An object of the present invention is to provide a precision cleaning method for parts and the like.

[0015]

According to the present invention, there is provided a method for precision cleaning of mechanical parts or the like, wherein a cleaning basket containing a large number of objects to be cleaned is suspended in a cleaning tank, and a cleaning liquid is supplied from an upper end or a lower end of the cleaning tank. By spraying air on the object to be cleaned and sucking air from the opposite side of the liquid spraying end of the tank, a two-phase co-current flow of cleaning liquid and air is formed around the object to be cleaned, and the cross section of the cleaning basket The air flow rate is 0.1 m / sec to 2.6 m / sec and the washing liquid flow rate is 15 m / hr to 150 m / hr.

As the cleaning liquid, pure water, a water-based cleaning liquid or the like is used.

More preferable conditions of the superficial velocity per section of the washing basket are an air velocity of 0.26 m / sec to 2.6 m / sec and a cleaning liquid velocity of 25 m / h to 150 m / h.

After the washing is completed, it is preferable that the spraying of the washing liquid is stopped and the suction of the air is continued to drain and dry the object to be washed.

[0019]

The washing basket containing a large number of objects to be washed is suspended in the washing tank, and the washing liquid is sprayed from the upper end or the lower end of the washing tank onto the object to be washed, and the opposite side of the liquid spraying end of the tank. To form a co-current two-phase flow of the cleaning liquid and the air around the object to be cleaned, and the air flow velocity is 0.1 m / sec.
By setting the flow rate of the cleaning liquid to 2.6 m / sec and the flow rate of the cleaning liquid to 15 m / hour to 150 m / hour, sufficient wetting and appropriate turbulence are given to the entire surface of the object to be cleaned.

Then, after the cleaning is completed, the spraying of the cleaning liquid is stopped and the suction of the air is continued, whereby the drainage and drying of the object to be cleaned are performed by utilizing the suction and circulation functions of the air.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. For the sake of simplicity, the lines for the replenisher and the drainage are not shown in FIGS.

The precision cleaning method for mechanical parts and the like according to the present invention is as follows.
As shown in FIG. 1, first, a washing basket (2) containing a large number of objects to be washed (A) is supported by a basket supporting frame (3) above a washing tank (1) having a substantially closed structure and suspended. Then wash basket
(2) The cleaning liquid (9) is sprayed uniformly on the upper surface of the object (A) by the spray (4) provided above. The cleaning liquid (9) flows down the gap between the small articles, which are the objects to be cleaned (A),
It flows into the gas-liquid separator (5). The cleaning liquid (9) is drawn from the bottom of the gas-liquid separator (5) by the pump (6),
Circulated and used as a cleaning solution for spraying. In addition, an air suction blower connected to the upper part of the gas-liquid separator (5)
(7) is activated and the air in the gas-liquid separator (5) is sucked and eliminated, so that the air between the lower part of the cleaning basket (2) and the cleaning tank (1) becomes negative pressure, and the cleaning basket ( 2) The surrounding air (10) is sucked from above, and the washing liquid and the air (10) flow downward in the washing basket (2).

The downward cocurrent of the cleaning liquid and the air (gas) becomes a continuous gas flow when the flow rate of the gas is small with respect to a constant flow rate of the cleaning liquid. However, when the flow rate of the gas increases, the transition flow is changed. After that, a pulsating flow is reached. Further, when the flow rate of the gas is increased, a part of the liquid becomes droplets and becomes a spray flow that accompanies the gas flow. Among these flow conditions, in the pulsating flow, the liquid film on the surface of the object to be cleaned (A) vibrates violently, and a liquid continuous phase portion in which bubbles are dispersed is locally formed, or the liquid continuous phase is formed. The portions are swept away by the gas flow to reveal portions of the gas continuous phase, or they are alternately formed to exhibit a pulsation phenomenon.

If this pulsating flow is used for cleaning, excessive energy is not required, and sufficient wetting and turbulence can be provided even in a portion that is difficult to clean such as a contact surface between the objects to be cleaned (A). . Therefore, without completely moving the cleaning basket (2) or using any of a number of other cleaning power enhancement auxiliary means, all the objects to be cleaned (A) in the cleaning basket (2) can be used.
Can be efficiently cleaned.

Specific conditions for realizing a flow state suitable for cleaning as described above include almost no relation to the shape and size of the object to be cleaned (A), regardless of the cross section of the cleaning basket (2). As the superficial flow velocity, the air velocity is 0.1 m / sec to 2.6.
m / sec, more desirably from 0.26 m / sec to 2.6 m / sec, and the cleaning solution flow rate is 15 m / hour (4.2 liter / m ^2).
Sec) to 150 m / hr (42 l / m ² sec), more preferably 25 m / hr (7 l / m ² sec) to 1
It is effective to set it to 50 m / hour (42 liter / m ² · second).

In the above embodiment, the soft packing (8) is attached to the basket support frame (3), whereby the cleaning tank (1) and the cleaning basket (2) at the basket support frame (3) are provided. )
The short path of air from the gap is minimized.
The air discharged from the air suction blower (7) is
The washing basket (2) may be circulated to the upper part of (1) and blown upward. As the washing basket (2), one having a circular, square or other polygonal cross section is appropriately used.

FIG. 2 shows another embodiment of the method for precision cleaning of mechanical parts and the like according to the present invention. In this example,
An ejector (11) is provided instead of the air suction blower (7), and both the air and the cleaning liquid collected in the gas-liquid separator (5) are circulated by the ejector (11), and the cleaning liquid containing air (12) Is sprayed on the object to be cleaned (A). Other configurations are the same as those in FIG. 1, and the same components are denoted by the same reference numerals and description thereof will be omitted.

As described above, as an apparatus for carrying out the method for precision cleaning of mechanical parts and the like according to the present invention, a cleaning tank (1) having a substantially closed structure and a cleaning liquid are circulated and sprayed on the upper surface of the object (A) to be cleaned. A mechanism, an air circulation mechanism for creating an air flow in the same direction as the cleaning liquid in the gap between the objects to be cleaned (A), and a cleaning tank
(1) A gas-liquid separator (5) at the outlet.

FIG. 3 illustrates an embodiment of a cleaning system using the above-described cleaning apparatus.

In FIG. 3, the cleaning tank (51) is covered with a lid (51a) which can be freely opened and closed, and the lid (51a) is provided with an air suction duct (61). Air intake duct (61)
Has an air intake damper that adjusts the amount of air intake
(62) and a filter (63) are provided. Spray (5
The header (54a) of (4) can be flipped up, the lid (51a) of the cleaning tank (51) is opened, and the header (5) of the spray (54) is opened.
With the 4a) flipped up, the washing basket (52) is put in and out of the washing tank (51). In cleaning tank (51), packing (58)
A basket support frame (53) for supporting the cleaning basket (52) is provided. A cleaning liquid recovery path (64) is provided at the lower end of the side wall of the cleaning tank (51).
The gas-liquid separator (55) communicates with the cleaning tank (51) via (64). The liquid used for cleaning is the cleaning liquid recovery path (64)
The bottom wall of the cleaning tank (51) is inclined downward toward the cleaning liquid recovery path (64) in order to facilitate the flow. Above the gas-liquid separator (55), a duct (65) for taking out the air separated in the gas-liquid separator (55) is provided. A circulation blower (57) and a heater (66) are provided in the air extraction duct (65). The air heated by the heater (66) is introduced into the cleaning tank (51) from a circulating air introduction duct (67) provided at the upper end of the side wall of the cleaning tank (51), and a part of the air is discharged into the exhaust duct (51). 68) exhausted as appropriate.
The exhaust duct (68) is provided with an exhaust port damper (69) for adjusting the amount of exhaust air.

The cleaning device of the embodiment shown in FIG.
The cleaning process is performed in three stages: main cleaning and final cleaning. The pre-cleaning solution tank (70A) and the main cleaning solution tank (70
Three tanks are provided: B) and a finish cleaning liquid tank (70C). The cleaning liquid in each of the tanks (70A) (70B) (70C) is sprayed by the pre-cleaning liquid circulating pump, the main cleaning liquid circulating pump and the finishing cleaning liquid circulating pump (56A) (56B) (56C), respectively. Sent. Each pump (56A) (56B) (5
6C) to the spray (54), a pre-cleaning liquid introduction opening / closing valve (71A) and a main cleaning liquid introduction opening / closing valve (7
1B) and an opening / closing valve (71C) for introducing the finishing cleaning liquid are provided. Further, the washing and drainage liquid separated in the gas-liquid separator (55) is supplied to one of the tanks (70A) (70B)
(70C), and in the middle of the piping from the gas-liquid separator (55) to each tank (70A) (70B) (70C), a pre-cleaning liquid recovery opening / closing valve (72A) and a main cleaning liquid A recovery opening / closing valve (72B) and a finishing cleaning liquid recovery opening / closing valve (72C) are provided. The pre-cleaning liquid tank (70A), the main cleaning liquid tank (70B) and the finishing cleaning liquid tank (70C) are provided with opening / closing valves (74A) (74B) (74C) for replenishing the cleaning liquid, respectively, and each pump (56A) (56B) (5
In the middle of the pipe from 6C) to the spray (54), there are provided opening / closing valves (73A), (73B), and (73C) for extracting the contaminated cleaning liquid that can be opened when the contaminated cleaning liquid is discharged. Although not shown, each valve is opened and closed by a solenoid valve or the like linked to a timer or the like.

The following procedure is used for precision cleaning of small articles such as machine parts by this apparatus.

A) The lid (51a) of the cleaning tank (51) is in an open state, and the header (54a) of the spray (54) is in a state of being flipped up, and the object to be cleaned (A) is placed in the cleaning tank (51). A cleaning basket (52) full of small articles such as a mechanical part is inserted.

B) Next, the header (54) of the spray (54)
a) is set in place, and the lid (51) of the washing tank (51) is
a) Close. Then, the circulation blower (57) is started, and a predetermined flow rate (0.1 m / sec to 2.
(6 m / sec). At this time, the opening degree of the air suction port damper (62) and the opening degree of the exhaust port damper (69) are adjusted so that the air pressure in the cleaning tank (51) is slightly lower than the atmospheric pressure. Adjust in advance to obtain the required ventilation volume.

C) Next, in the pre-cleaning step, the pre-cleaning liquid introduction opening / closing valve (71A) and the pre-cleaning liquid recovery opening / closing valve (72A) are opened, and the pre-cleaning liquid circulation pump (56A) is opened.
Is started, the pre-cleaning liquid is sent to the spray (54), and the pre-cleaning liquid is evenly sprayed on the upper surface of the object (A) from above the cleaning basket (52). The flow rate of the liquid is 15 m /
Hours to 150 m / hour By doing so, the gas-liquid flowing between the objects to be cleaned (A) becomes a pulsating flow,
The object to be cleaned (A) in the cleaning basket (52) wets all surfaces and provides sufficient turbulence to promote cleaning. After a preset cleaning time, the liquid circulation pump (56A) is stopped, and the liquid introduction opening / closing valve (71
A) Close, stop the circulation of the cleaning solution, and continue only the air circulation. The cleaning liquid adhering to the surface of the object to be cleaned (A) is blown off by the circulating air, including the liquid held in the gap between the parts by surface tension, and is drained. This liquid is collected in the pre-cleaning liquid tank (70A), and at the end of the recovery, the pre-cleaning liquid collecting open / close valve (72A) is closed.

D) Next, in the main cleaning step, the main cleaning liquid introduction opening / closing valve (71B) and the main cleaning liquid collection opening / closing valve (72B) are opened, and the main cleaning liquid circulation pump (56B) is started to discharge the main cleaning liquid. It is sent to the spray (54) and sprayed uniformly on the upper surface of the object (A) from above the washing basket (52). Less than,
c) the time required to obtain the required cleanliness under sufficient wetting and turbulence, as in the pre-cleaning step of c);
Perform cleaning. Cutting off and collecting the adhering liquid after washing is the same as in the preliminary washing step c).

E) Then, as a finish cleaning step, c)
The same operation as in the pre-cleaning step (d) and the main cleaning step d) is carried out to remove a small amount of the main cleaning liquid which adheres to the object (A) to be cleaned and causes spots.

F) Next, in the drying step, after the finish cleaning agent is sufficiently blown off from the surface of the object (A) to be cleaned, if the operation of the circulation blower (57) is continued, the object (A) Is dried. It is preferable that the cleaning liquid used in the previous cleaning step is slightly heated (for example, to 50 ° C. or higher), so that heat is accumulated in the object (A) to be cleaned during the cleaning step. In addition, the time required for the drying step can be significantly reduced.

G) Next, the circulation blower (57) is stopped, the lid (51a) of the washing tank (51) is opened, and the header (5) of the spray (54) is opened.
4a) is flipped up and the object to be cleaned (A) is taken out together with the cleaning basket (52).

Thus, one batch is completed.

In the above embodiment, the cleaning process is performed in three steps (preliminary cleaning, main cleaning and finish cleaning). However, the present invention is not limited to this. Depending on the degree of cleanliness, the type of cleaning liquid used may be more or less.

Examples of the cleaning liquid include, for example, hot pure water after the preliminary cleaning liquid has been used for the final cleaning (rinsing), an alkaline cleaning agent whose concentration has been adjusted for the main cleaning liquid, hot pure water for the final cleaning liquid, or There are various combinations, such as hot pure water after use for cleaning, hot pure water after using the main cleaning liquid for finish cleaning, and hot pure water for newly using the finishing cleaning liquid. The present invention is not limited to the use of a specific cleaning liquid, but provides an apparatus which is effective when only water or an aqueous cleaning liquid is used.

The transfer of the cleaning liquid between the cleaning liquid tanks (70A) (70B) (70C) is performed by the liquid introduction valves (71A) (71B) (71C) and the liquid recovery valves (72A) (72B) (72C) Opening and closing and operation of the pump. These operations can be automated or performed manually. In addition, withdrawal of the contaminated cleaning liquid and replenishment of the new cleaning liquid are naturally necessary, and are performed according to conventionally used judgment criteria.

The opening and closing mechanism of the lid (51a) of the cleaning tank (51)
There are various types of mechanisms for raising the header (54a) of the spray (54) and for transporting and inserting the cleaning basket (52), and the present invention does not specify a specific one. In addition, the number of the cleaning tanks, the flow of the cleaning liquid, the method of the intermediate treatment, and the like are appropriately changed and implemented.

[0045]

According to the precision cleaning method for mechanical parts and the like of the present invention, sufficient wetting and appropriate turbulence are given to the entire surface of the object to be cleaned, so that the object to be cleaned is swung or rotated. Even without this, it is possible to reliably and precisely clean all the mechanical parts and the like in the cleaning basket using pure water or a water-based cleaning agent.

Further, since excessive local physical force does not act like ultrasonic waves, problems such as erosion do not occur even if aluminum parts are cleaned.

By draining and drying the object to be cleaned by utilizing the air suction / circulation function,
With a simple system, a highly efficient and economical cleaning device can be obtained.

[Brief description of the drawings]

FIG. 1 shows a method for precision cleaning of mechanical parts and the like according to the present invention.
It is a figure which shows an example schematically.

FIG. 2 is a view schematically showing another example of the method for precision cleaning of mechanical parts and the like according to the present invention.

FIG. 3 is a view schematically showing another example of the precision cleaning method for mechanical parts and the like according to the present invention.

FIG. 4 is a view schematically showing an example of a conventional precision cleaning method for mechanical parts and the like.

FIG. 5 is a view schematically showing another example of a conventional precision cleaning method for mechanical parts and the like.

FIG. 6 is a flowchart showing another example of a conventional precision cleaning method for mechanical parts and the like.

[Explanation of symbols]

 (1) (51) Cleaning tank (2) (52) Cleaning basket (4) (54) Spray (5) (55) Gas-liquid separator (7) (57) Air suction blower (A) Object to be cleaned

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazunori Kiba 5-28 Nishikujo, Konohana-ku, Osaka-shi Inside Tachibana Shipbuilding Co., Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name) B08B 3 / 02

Claims (2)

(57) [Claims] 1. A washing basket containing a large number of objects to be washed is suspended in a washing tank, and a washing liquid is sprayed on an object to be washed from an upper end or a lower end of the washing tank. By sucking air from the opposite side, a co-current two-phase flow of the cleaning liquid and air is formed around the object to be cleaned, and the air flow velocity is 0.1 m as the superficial flow velocity per cross section of the cleaning basket.
/ S to 2.6 m / s, and the flow rate of the washing solution is 15 m / h to 150
m / hour. A precision cleaning method for mechanical parts, etc. 2. The precision of machine parts and the like according to claim 1, wherein after the cleaning is completed, the spraying of the cleaning liquid is stopped and the suction of air is continued to drain and dry the object to be cleaned. Cleaning method.