JP5984920B2 - Non-cyanide-based electropolishing - Google Patents

Description

  Embodiments of the present invention relate to jewelry manufacture, and more specifically, but not limited to, embodiments of the present invention relate to a method of polishing jewelry in a jewelry manufacturing process.

  The jewelry industry is currently growing around the world. With the growing demand for jewelry, the jewelry manufacturing industry is required to optimize jewelry manufacturing methods in order to produce more jewelry in a minimal amount of time and meet customer expectations. Furthermore, very high demands are placed on the quality of the jewelry, in particular the high reflectivity of the surface of the jewelry product.

  In general, jewelry products are polished and sent to the market so that the surface has a fine finish and high reflectivity. Conventionally, the metal polishing process is carried out by manually buffing with various types of cotton, chemical grinding wheels, etc., in order to give the jewelry product a mirror finish.

  Another existing method for polishing jewelry is an electropolishing process using a cyanide solution. Electropolishing using a cyanide solution is a battery consisting of two electrodes that are electrically connected and immersed in a cyanide-based solution (electrolyte): a positive electrode (anode) and a negative electrode (cathode). Is done using. Further, the metal to be polished is connected to the positive electrode, and when current passes through the battery, excess metal is removed from the positive electrode (anode) and dissolved in the electrolyte.

  As described above, since the cyanide electrolyte used in the conventional metal polishing method is toxic, the entire process is dangerous and requires careful handling throughout the polishing process. Moreover, residual sludge of cyanide is becoming a major concern for metal surface treatment companies. This is due to the limited disposal options for sludge containing cyanide, which is time consuming and costly. Furthermore, in the case of mass production, the total time spent greatly affects the overall efficiency of the process. Furthermore, in the conventional polishing method, gas is generated as ions pass through the electrolytic cell. The gas generated in the electrolyzer contains suspended particles that are harmful to health and can cause environmental problems.

  Furthermore, conventional metal polishing methods are not efficient for polishing complex shaped jewelry (eg, jewelry with grooves), which makes the entire process partially inefficient. In addition, conventional methods for polishing gold jewelry cannot completely recover the gold lost during the polishing process, leading to gold loss.

  Therefore, there is a need in the jewelry manufacturing industry for a system that can overcome the aforementioned weaknesses and reliably improve efficiency. Furthermore, there is a need for a system that can be used to improve the efficiency of metal polishing.

  The main objective of the present invention is to provide an environmentally friendly metal polishing system.

  Another object of the present invention is to provide a metal polishing system that can be used for mass production.

  It is a further object of the present invention to provide a system that can remove harmful gases generated during metal polishing.

  Yet another object of the present invention is to provide a metal polishing system that minimizes metal loss to a negligible amount.

  The present invention is illustrated in the accompanying drawings, wherein like reference numerals designate corresponding components throughout the drawings. Embodiments of the present invention will be better understood by reading the following description with reference to the drawings.

1 is a perspective view of a metal polishing system according to an embodiment of the present invention. It is a flowchart explaining the metal grinding | polishing process by embodiment of this invention. 1 illustrates a system that can remove harmful gases generated during metal polishing according to an embodiment of the present invention. FIG.

  Embodiments of the present invention, as well as their various features and advantageous details, are more fully described with reference to non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. In order to avoid unnecessarily obscuring embodiments of the present invention, descriptions of well-known components and processing techniques are omitted. The examples used herein are intended only to facilitate an understanding of how to implement the embodiments of the present invention and to further enable those skilled in the art to practice the embodiments of the present invention. Has been. Accordingly, the examples should not be understood as limiting the scope of the embodiments of the present invention.

  Embodiments of the present invention provide an environmentally friendly metal polishing system. Furthermore, embodiments of the present invention provide an electric tractor that can enable multi-speed shifting. Furthermore, embodiments of the present invention provide a system that can remove harmful gases generated during the metal polishing process. Hereinafter, each drawing (specifically, FIGS. 1 to 3) in which an embodiment is shown will be referred to. Throughout these drawings, like reference numerals indicate corresponding features.

  FIG. 1 shows a perspective view of a metal polishing system according to an embodiment of the present invention. System 100 includes a base assembly 102 and an electrolytic cell assembly 130. The base assembly 102 includes a support stand 104 that may be made of wood or other insulating material. The support stand 104 is attached to the connection component 106. The connecting piece 106 further extends from the support stand 104 to a wheel 108 that is used to move, rotate, and secure the system 100 to the ground. In addition, the base assembly 102 includes a column 112, which includes a first end 112a and a second end 112b. The second end portion 112 b of the column 112 is connected to the support stand 104 through the extended portion 110. Furthermore, the first end portion 112 a of the column 112 is connected to the first end portion 116 a of the shaft 116 via the swelling joint 114. The shaft 116 extends in an axial direction perpendicular to the axis of the column 112 and the swelling joint allows the shaft 116 to pivot 360 degrees along the axis indicated by the arrow 115. Further, the second end portion 116 b of the shaft 116 is connected to the plurality of cylinders 120 via the rotor 118. Rotor 118 is adapted to provide a plurality of cylinders 120 with rotational movement along the axis and direction indicated by arrow 119. The base assembly 102 further includes a holding cylinder 122 that includes a hook 124 or similar means adapted to hold the anode fixture 134.

  In addition, the electrolyzer assembly 130 includes a glass beaker 132 that surrounds the anode fixture 134, cathode strip 136, thermostatic heater 142, and non-cyanide based stripping solution (not shown). It is adapted to. The anode fixture 134 includes a hook 126, or similar means, adapted to hold the anode fixture 134 to the holding cylinder 122 at its upper end 134a. Further, the portion of the anode fixture 134 located inside the glass beaker includes a plurality of hooks 138, which are arranged in a row of rows, and a product to be polished (not shown) is arranged. Adapted to hold. However, it should be noted that the anode fixture 134 may be a different design and structure as long as it does not interfere with the intended function of the system 100. This will be clear from the description of the embodiments of the present invention. Such anode fixtures 134 having different designs and structures are also within the scope of the present invention. Furthermore, the electrolytic cell assembly 130 is provided with a plurality of cathode strips 136 between the anode fixture 134 and the glass beaker 132. The heater 142 with the thermostat is electrically connected to the control panel rectifier 126. For example, the heater with the thermostat is connected to the control panel rectifier by the cable 128. The control panel rectifier is used to control parameters such as voltage and temperature, and is used to convert alternating current into direct current.

  FIG. 2 shows a flowchart illustrating a metal polishing process 200 according to an embodiment of the present invention. A cyanide-free stripping solution (eg, a thiourea-based solution) is taken into the glass beaker 132 of the electrolyzer assembly 130 and heated to 80 degrees Celsius (step 201). In one embodiment, the stripping solution is prepared by uniformly mixing a desired amount of distilled water, thiourea, reducing sugar, activated acid, and wetting agent in a suitable container. In one embodiment, 1 liter of distilled mineral water is taken into a glass beaker or similar means. The distilled water is preheated to about 75 degrees Celsius. Next, 65 grams of thiourea is added to the preheated water and stirred until completely dissolved. Next, 100 grams of reducing sugar is added to the mixture of thiourea and distilled water. As reducing sugar is added, the stirring temperature of the solution decreases. Next, 40 ml of activated acid and about 30 to 50 ml of wetting agent are added to a solution of thiourea, distilled water, and reducing sugar, and the mixture is stirred and mixed uniformly. Note that the step of preparing the stripping solution described above is given to facilitate understanding of the embodiment of the present invention. However, the various steps provided in the above method may be performed in the above order, in a different order, or may be performed simultaneously. Further, in some embodiments, one or more steps listed in the above method may be omitted. Accordingly, any modifications apparent from such embodiments, as well as the specification and drawings are within the scope of the invention. FIG. 3 is a flowchart illustrating a method of preparing a stripping solution according to an embodiment of the present invention.

  Next, the product to be polished is attached to the anode fixture 134 using the plurality of hooks 138 (step 202). For example, the anode fixture is designed to hold nine products to be polished at a time. In one embodiment, the anode fixture is a jig made of titanium. However, it should be noted that the anode fixture 134 may be a different design and structure as long as it does not interfere with the intended function of the system 100. This will be clear from the description of the embodiments of the present invention. The anode fixture 134 is attached to the holding cylinder 122 by hooks 124 and 140 together with the product to be polished. Next, a cathode strip 136, preferably made of stainless steel plate, is placed inside the glass beaker 132 so that it is located between the anode fixture 134 and the glass beaker 132. However, the cathode strip 136 may be selected from any metal such as a titanium plate, a gold plate, or a platinum plate. The area ratio of anode to cathode is preferably maintained at 1: 1. Next, the cathode strip 136 and the anode fixture 134 are placed in the glass beaker 132 of the electrolytic cell assembly 130 such that the cathode strip 136 surrounds the anode fixture 134 (or the anode fixture 134 surrounds the cathode strip 136). To do. However, it should be noted that the anode fixture 134 and cathode strip 136 may be positioned in the glass beaker 132 of the electrolyzer assembly in various ways as long as they do not interfere with the intended function of the system 100. This will be clear from the description of the embodiments of the present invention. Next, the cathode strip 136 is connected to the negative electrode, and the anode fixture 134 is connected to the positive electrode (step 203).

  Next, a voltage of about 15-18 volts is applied to the electrolyzer assembly 130 for about 2 minutes (step 204). Application, control and monitoring of the voltage is performed through the control panel rectifier 126. Next, when the desired voltage is applied, the anode fixture is rotated closer to the cathode strip. As a result of the voltage being applied, excess metal is etched / removed from the anode fixture, and the etched / removed metal precipitates in the stripping solution (step 205). In another embodiment, the metal removed from the anode is deposited in the cathode. The process of depositing metal on the cathode is similar to the plating process. Thus, in addition to the polishing operation (which removes excess metal from the product to give a quality finish to the product), this step is a plating operation (which deposits metal on the product to give the product a fine finish). Can also be used.

  Electropolishing is performed and the anode fixture is removed from the holding cylinder 122. As described above, by rotating the pillar 114 and the support stand 116 along their respective axes, the anode fixture 136 can be easily attached to and detached from the holding cylinder. After performing the electropolishing process, the product is removed from the anode fixture and the polished product attached to the anode fixture is replaced with the next batch of unpolished product (step 206). This process (steps 203, 204, 205, and 206) is repeated until all products are polished. In addition, each metal grinding | polishing step mentioned above is presented so that it may be easy to understand the embodiment of the present invention. However, the various steps provided in the above method may be performed in the above order, in a different order, or may be performed simultaneously. Further, in some embodiments, one or more steps listed in the above method may be omitted. Accordingly, any modifications apparent from such embodiments, as well as the specification and drawings are within the scope of the invention.

  Further, excess gold removed from the product during the polishing process and deposited on the cathode peels off to the bottom of the bath after multiple batches of product are polished using the non-cyanide based electropolishing method described above. Thereafter, the tank is decanted to collect the gold, and the collected gold is washed out with water and melted in a furnace to recover solid gold, which is almost 100% (step 207). In another embodiment, system 100 is provided with cathode strip 136 and anode fixture 134 in a 1: 2 ratio.

  In another embodiment, the system 100 includes a scrubber device 144. FIG. 3 illustrates a system capable of removing harmful gas 143 generated in a metal polishing process according to an embodiment of the present invention. The scrubber device 144 includes a valve 146 and a scrubber water 148. In one embodiment, the scrubber water is distilled mineral water. Further, the scrubber device 144 is provided in the system 100 so that the gas 143 generated in the electrolytic cell assembly 130 can be passed during the plating process. In one embodiment, the gas 143 generated in the electrolyzer assembly 130 flows into the scrubber device 144 through the vent 150. The scrubber device 144 further includes a piping 152 that allows steam communication between the valve 146 and the scrubber water 148. In one embodiment, gas 143 generated within electrolyzer assembly 130 includes suspended particles that are harmful to the environment. The valve 146 operates as a mist eliminator and is configured to remove acidic substances from the gas 143. Scrubber water 148 is configured to receive gas 143 from valve 146 through piping 152. In addition, the scrubber water 148 removes all suspended particles from the gas 143 and provides clean air 153. Further, the clean air 153 is vented to the atmosphere.

  The process of removing harmful gas generated during the metal polishing process according to the embodiment of the present invention includes supplying power to the scrubber device 144. In one embodiment, power is supplied to the scrubber device 144 from the control panel rectifier 126. The power supply of the scrubber device 144 is performed before the start of the polishing process in the electrolytic cell assembly 130. The pH value of the scrubber water 148 is measured. If the scrubber water 148 is identified as acidic, fresh distilled water is used as the scrubber water 148. Next, the electropolishing disclosed by method 200 is performed and gas generated during electropolishing is caused to flow into valve 146 via vent 150. Further, the valve 146 operates as a mist eliminator and removes acidic substances from the gas. The scrubber water 148 is configured to receive gas from the valve 146 via the pipe 152. In addition, the scrubber water 148 removes all suspended particles from the gas and provides clean air 153. In addition, clean air is vented into the atmosphere 153.

Since the foregoing description of specific embodiments has revealed in greater detail the general nature of embodiments of the present invention, others have applied the current knowledge to the general concept. It will be readily possible to modify and / or adapt such particular embodiments for various applications without departing. Accordingly, such adaptations and modifications must be understood and intended to be understood within the spirit and scope of the equivalents of the embodiments of the present disclosure. It should be understood that the wording and terminology used herein is for the purpose of illustration and not limitation. Thus, while embodiments of the present invention have been described in terms of preferred embodiments, as will be appreciated by those skilled in the art, embodiments of the present invention are intended to be within the spirit and scope of the embodiments described herein. May be implemented with modifications.
[Appendix 1]
A metal polishing system including an electrolyzer assembly, the electrolyzer assembly comprising:
An anode fixture connected to the positive electrode and configured to receive a plurality of metals to be polished;
A cathode connected to the negative electrode;
A stripping solution configured to allow ions to move between the anode fixture and the cathode;
The stripping solution does not contain cyanide,
system.
[Appendix 2]
The system according to claim 1, wherein the anode fixture is selected from a jig made of titanium.
[Appendix 3]
The system of claim 1, wherein the cathode is selected from stainless steel.
[Appendix 4]
The system of claim 1, wherein the area ratio of the anode fixture and the cathode is maintained at 1: 1.
[Appendix 5]
The system of claim 1, wherein the stripping solution is a thiourea based solution.
[Appendix 6]
The system according to claim 1, wherein the stripping solution is a uniform mixture of thiourea and at least one of distilled water, reducing sugar, activated acid, and wetting agent.
[Appendix 7]
And further comprising a scrubber device provided in vapor communication with the electrolyzer assembly, the scrubber device comprising:
A valve configured to remove acidic material from gas generated within the electrolytic assembly;
Scrubber water configured to remove suspended particles from gas generated within the electrolysis assembly;
The system according to appendix 1.
[Appendix 8]
Preparing a stripping solution;
Preheating the stripping solution;
Providing in the stripping solution an anode connected to the positive electrode and a cathode connected to the negative electrode;
Applying a desired voltage to the anode and the cathode;
A metal polishing method comprising:
The anode includes a plurality of metals to be polished,
The stripping solution does not contain cyanide,
Method.
[Appendix 9]
The metal polishing method according to appendix 8, further comprising a step of cleaning a gas generated during the metal polishing.
[Appendix 10]
The metal polishing method according to appendix 9, wherein the stripping solution is a solution obtained by uniformly mixing thiourea with at least one of distilled water, reducing sugar, activated acid, and wetting agent.

Claims (7)

A metal polishing system that performs metal polishing and removes harmful gases generated during polishing,
A preheated stripping solution;
A base assembly configured to hold an anode fixture;
An electrolytic cell assembly,
The electrolytic cell assembly includes:
Which is connected to the positive electrode of the cell assembly, said configured to receive at least one polished metal anode fixture,
A cathode fixture connected to the negative electrode of the electrolyzer assembly ;
A said stripping solution ions are adapted to be moved between said cathode fixture and the anode fixture, and said stripping solution without cyanide,
A scrubber device provided in gas communication with the electrolyzer assembly;
The scrubber device
A valve configured to remove acidic material from gas generated within the electrolytic assembly;
Scrubber water configured to remove suspended particles from gas generated in the electrolysis assembly;
A pipe that enables steam communication between the valve and the scrubber water;
system.   The system of claim 1, wherein the anode fixture is selected from a titanium jig. The system of claim 1, wherein the cathode fixture is selected from stainless steel. The system of claim 1, wherein an area ratio of the anode fixture and the cathode fixture is maintained at 1: 1.   The system of claim 1, wherein the stripping solution is a homogeneous mixture of thiourea and at least one of distilled water, reducing sugar, activated acid, and wetting agent. A metal polishing method for performing metal polishing and removing harmful gas generated during polishing, comprising the step of preparing a stripping solution;
Preheating the stripping solution;
Providing a base assembly configured to hold an anode fixture;
Providing an electrolyzer assembly;
The electrolytic cell assembly includes:
Which is connected to the positive electrode of the cell assembly, said configured to receive at least one polished metal anode fixture,
A cathode fixture connected to the negative electrode of the electrolyzer assembly ;
A the stripping solution ions are adapted to be moved between said cathode fixture and the anode fixture, the stripping solution is the preheating cyanide-free,
A scrubber device provided in gas communication with the electrolyzer assembly;
The scrubber device
A valve configured to remove acidic material from gas generated within the electrolytic assembly;
Scrubber water configured to remove suspended particles from gas generated in the electrolysis assembly;
A pipe that enables steam communication between the valve and the scrubber water;
Method. The metal polishing method according to claim 6, wherein the stripping solution is a uniform mixture of thiourea and at least one of distilled water, reducing sugar, activated acid, and wetting agent.

Images