Cleaning assembly for a surface of a roller   

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to a cleaning assembly, and more particularly to a cleaning assembly used to clean a surface of a roller thoroughly to prevent the roller from contaminating objects on the roller.

2. Description of the Related Art

An object with laser patterns such as a security label with a holographic laminating film, laser hologram or the like is coated, printed or the like with a laser ceramic anilox rollers (hereinafter referred to as rollers). A process for forming the laser patterns generally is an automatic process comprising (a) grinding surfaces of the rollers to make the surfaces of the rollers smooth; (b) polishing the surfaces of the rollers to make the surfaces of the rollers like mirror; (c) then forming laser patterns on the surfaces of the rollers by laser cutting and engraving system; (d) fine polishing the surfaces of the rollers after the surfaces is engraved; (e) finally, cleaning the surfaces of the rollers to keep the surfaces clean.

During the laser patterns are formed at the step of (c), protrusions protruding form the surfaces and residues such as ceramic powders, particles or other contamination are generated. Therefore, polishing the surfaces of the rollers at the step of (d) comprises eliminating protrusions on the surfaces to make the surfaces smooth like a mirror. The residues are still remained on the surfaces of the rollers after the step (d), therefore, the step of (e) comprises cleaning the surfaces.

A conventional clean method for cleaning the surfaces comprises spray sodium bicarbonate (NaHCO3) with a high pressure toward the surfaces to clean the surfaces. Although the conventional clean method is able to remove the residues, white powders of sodium bicarbonate will be embedded in meshes, cavities, or cells (hereinafter referred to as cells) in the surfaces of the rollers to contaminate objects treated by the rollers to form holographic pattern or the like.

In case the foregoing disadvantages, another conventional clean method for cleaning the surfaces comprises immersing the rollers into a water tank or a solvent tank using supersonic vibration to remove the residues from the surfaces of the rollers. The residues precipitate in the tank. However, the automatic process of the conventional clean method further comprises a step of drying the rollers after the step of (e). Therefore, a cost of the automatic process will be increased. In addition, after water or solvent is dried, water stains will be formed on the surfaces to affect the object treated by the roller to generate undesired patterns.

Although the inventor had considered impacting the surfaces by high-pressure gas to clean the surfaces, the high-pressure gas cannot provide enough kinetic energy to the residues in the cells, so the residues in the cells cannot be removed from the cells. As a result, a method for not only cleaning the surfaces but also removing the residues from the cells is still being sought.

Therefore, the present invention provides a cleaning assembly for a surface of a roller to mitigate or obviate the aforementioned problems.

SUMMARY

The primary objective of the present invention is to provide a cleaning assembly used to remove residues from a surface of a roller allowing the surface to be cleaned thoroughly to prevent the roller from contaminating objects on the roller.

To achieve the objective, the cleaning assembly in accordance with the present invention comprises a dry-ice container, a connector and an injector. The dry-ice container contains carbon dioxide (CO2). The connector has two ends and one end connects the dry-ice container. The injector is mounted on the other end of the connector, is coupled with the connector and the dry-ice container and allows CO2 to be sprayed out of the injector toward the surface of the roller. Because CO2 is solid when it is sprayed out of the injector toward the surface of the roller, the solid CO2 provides enough kinetic energy to residues in cells of the roller. Therefore, the residues can be removed from the cells. Additionally, after the solid CO2 impacts the surface of the roller, the solid CO2 sublimates directly to a gas CO2, so there is no stain or other spot to be remained on the surface of the roller.

Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a deployment diagram of a cleaning assembly for a surface of a roller in accordance with the present invention;

FIG. 2 is a front view of a machine with a roller to be cleaned by a cleaning assembly in accordance with the present invention;

FIG. 3 is an operational side view of the cleaning assembly for the surface of the roller in FIG. 1 cleaning the surface of the roller.

DETAILED DESCRIPTION

As used herein “Dry ice” is referred to solid carbon dioxide (CO2), which is usually used as a cooling agent. The dry ice sublimates from a solid directly to a gas at normal atmospheric pressure. Its sublimation point is −78.5° C. (−109.3° F.). The dry ice can be pressurized to turn into a liquid.

With reference to FIGS. 1 and 2, a cleaning assembly for a surface of a roller (21) in accordance with the present invention has a dry-ice container (10), a connector (11), a pressure controller (12), an injector (13) and a fixing apparatus (14). The roller (21) is mounted in a machine (20) and may be a laser engraved ceramic anilox roller. The machine rotates the roller (21) along a center fixed axis by designed control motor. The machine has at least one driver (22) to drive the roller (21) to move along a track (23).

The dry-ice container (10) may be a tank, a steel bottle, a steel drum or the like, which is used to contain high-pressure liquid phase of CO2. The dry-ice container (10) is preferably a steel drum that can be move conveniently. The dry-ice container (10) contains liquid carbon dioxide (CO2).

The connector (11) is a flexible hose that is cold temperature resistant and may be made of metal or polymer. The connector (11) has two ends, an outer surface and a protective sleeve. One of the ends of the connector (11) is coupled with the dry-ice container (10). The protective sleeve is mounted around the connector (11) in case an operational person frostbites by touching the connector (11).

The pressure controller (12) connects with the dry-ice container (10) to control an output pressure of the liquid gas allowing the liquid gas to become a solid when the liquid gas is output from the dry-ice container (10). The output pressure is preferred to be controlled between 15˜30 kg/cm2.

With further reference to FIGS. 3A and 3B, the injector (13) is mounted on the other end of the connector (11), is coupled with the connector (11) and the dry-ice container (10) and allows the solid, may be dry ice to be sprayed out of the injector (13) toward the surface of the roller (21). The injector (13) is preferably a tapered nozzle with a spray angle that is equal or smaller than 30°.

The fixing apparatus (14) is coupled with the connector (11) near the injector (13) to fix the injector (13) and allow the injector (13) to spray steadily toward the surface of the roller (21). The fixing apparatus (14) may be mounted on the machine (20) or may be a bracket standing on the ground without connecting with the machine (20).

Because CO2 is solid when it is sprayed out of the injector (13) toward the surface of the roller (21), the solid CO2 provides enough kinetic energy to residues in cells of the roller (21). Therefore, the residues can be removed from the cells. Additionally, after the solid CO2 impacts the surface of the roller (21), the solid CO2 sublimates directly to a gas CO2, so there is no stain or other spot to be remained on the surface of the roller (21). Accordingly, the clean assembly of the present invention has an excellent clean effect.

Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.