APPARATUS HAVING FRICTION PREVENTING FUNCTION, AND METHOD FOR MANUFACTURING AND DRIVING SAME

TECHNICAL FIELD

The present disclosure relates to an apparatus related to friction, and more particularly, to an apparatus with a friction preventing function and a method of manufacturing the apparatus.

BACKGROUND ART

An object that rolls, rotates, or linearly moves contacts another relevant object, and thus, friction between the two objects is generated. Such friction is necessary for a start operation and a stop operation of an object. However, friction may be a factor to hinder continuity of motion of a moving object.

Friction generated during motion of an object generates heat, which may affect not only the moving object but also other objects related to the moving object.

Accordingly, oil or grease may be used to decrease the friction. However, the oil and the grease are harmful to the environment. Also, friction may not be completely decreased only by using oil or grease. Oil and grease have a lower performance as time passes, and accordingly, the efficiency of the oil or the grease is decreased as time passes.

DETAILED DESCRIPTION OF THE INVENTION

TECHNICAL PROBLEM

Provided is an apparatus with a friction preventing function using an electrical method.

Also provided is a method of manufacturing the apparatus.

TECHNICAL SOLUTION

According to an aspect of the present invention, an apparatus with a friction preventing function, the apparatus includes a first object; a second object spaced apart from the first object and facing the first object; and a plurality of charged nanoparticles provided on a surface of one of the first and second objects, wherein a potential difference is formed between the first and second objects.

The nanoparticles may be positively charged and adhere to one having a lower potential of the first and second objects.

The nanoparticles may be negatively charged and adhere to one having a higher potential of the first and second objects.

Each of the nanoparticles may include a core having charged charges and a shell surrounding the core.

The apparatus may further include a material film covering the nanoparticles and filling gaps between the nanoparticles.

The first object may have an outer circumferential surface, and the second object may surround the outer circumferential surface.

The first object may be a flat panel, and the second object may be a carrier moving on the flat panel.

The first object may be a rail, and the second object may surround the rail.

The first and second objects may include conductive layers in a portion where the first and second objects face each other.

The material film may be paint or paste.

The first object may be a conductive pipe, and the second object may be a movable body that moves inside the pipe.

The pipe may be a gun barrel or a cannon barrel, and the second object may be a bullet or a cannon ball.

The nanoparticles may be uniformly distributed or may be uniformly distributed only in a plurality of areas spaced part from one another.

According to another aspect of the present invention, a method of manufacturing an apparatus, the method includes attaching a plurality of nanoparticles on a first object; disposing a second object to face the first object across the nanoparticles; charging the nanoparticles; and forming a potential difference for preventing friction in the first and second objects.

Each the nanoparticles may include a core having charged charges and a shell surrounding the core.

The charging of the nanoparticles may include forming a potential difference greater than the potential difference for preventing friction between the first and second objects.

The attaching of the nanoparticles may include forming a material film that covers the nanoparticles and fills gaps between the nanoparticles.

According to another aspect of the present invention, a method of manufacturing an apparatus, the method includes charging nanoparticles; attaching the charged nanoparticles onto a first object; disposing a second object to face the first object across the nanoparticles; and forming a potential difference for preventing friction in the first and second objects.

Each the nanoparticles may include a core having charged charges and a shell surrounding the core.

The attaching of the nanoparticles may include forming a material film that covers the nanoparticles and fills gaps between the nanoparticles.

ADVANTAGEOUS EFFECTS

An apparatus with a friction preventing function according to an embodiment of the present invention uses charged nanoparticles without using oil or grease and prevents friction between two objects by using an electrical method of applying a DC voltage to two objects concerned in friction.

Accordingly, the apparatus with a friction preventing function may be environmentally friendly.

In addition, since friction is controlled by simply applying a DC voltage, it is possible to maintain constant performance for a long period of time and to obtain an excellent energy efficiency.

DESCRIPTION OF THE DRAWINGS

• FIGS. 1A to 2C are mimetic diagrams for describing a basic principle applied to an apparatus with a friction preventing function according to an embodiment of the present invention;
• FIG. 3 is a cross-sectional view of a nano particle used in an apparatus with a friction preventing function, according to an embodiment of the present invention;
• FIGS. 4 to 7 are cross-sectional views of apparatuses with a friction preventing function according to embodiments of the present invention;
• FIG. 8 is a cross-sectional view of the apparatus shown in FIG. 6 including a nano material film instead of nano particles;
• FIG. 9 is an enlarged cross-sectional view of a region A1 of FIG. 8;
• FIG. 10 is a cross-sectional view of the apparatus shown in FIG. 4 including a nano material film instead of nano particles;
• FIG. 11 is a cross-sectional view of an apparatus with a friction preventing function according to another embodiment of the present invention;
• FIG. 12 is a cross-sectional view of an apparatus with a friction preventing function including nano particles configured as a multi-layered structure according to an embodiment of the present invention; and
• FIGS. 13 and 14 are cross-sectional views for describing a method of manufacturing an apparatus with a friction preventing function.

MODE OF THE INVENTION

Hereinafter, the present invention will be described in detail by explaining exemplary embodiments of the invention with reference to the attached drawings. In the drawings, the thicknesses of layers and regions are exaggerated for clarity.

FIGS. 1A to 2C are mimetic diagrams for describing a basic principle applied to an apparatus with a friction preventing function according to an embodiment of the present invention.

FIGS. 1A and 1B are mimetic diagrams for describing movement of a positively charged point particle 14, according to an initial position of the point particle 14, between first and second flat panels 10 and 12 that are parallel to each other and to which a direct current (DC) voltage is applied.

Here, the point particle 14 may refer to a particle that does not internally have a structure like an electron, a proton, a positron, or the like. In FIG. 1, the point particle 14 may be a positron.

Referring to FIG. 1A, the first flat panel 10 and the second flat panel 12 face each other and are spaced apart from each other at a predetermined distance H1. The first and second flat panels 10 and 12 are conductors. The first and second flat panels 10 and 12 are connected to a power source 16. The power source 16 may be a DC power source. The first flat panel 10 is connected to a positive electrode of the power source 16. The second flat panel 12 is connected to a negative electrode of the power source 16. An area between the first and second flat panels 10 and 12 is divided into a first area B1 and a second area B2. A boundary 18 between the first and second areas B1 and B2 is spaced apart from the first flat panel 10 at a first length L1. The first area B1 is an area between the first flat panel 10 and the boundary 18, and the second area B2 is an area between the boundary 18 and the second flat panel 12. A location of the boundary 18 may vary according to a size of the power source 16, or the like.

The boundary 18 may be closer to the first flat panel 10 than the second flat panel 12.

In FIG. 1A, when the positively charged point particle 14 is located in the second area B2 at an early stage, the point particle 14 moves toward the second flat panel 12 to adhere to the second flat panel 12.

As shown in FIG. 1B, if the point particle 14 is located in the first area B1 at an early stage, even though the point particle 14 is positively charged, the point particle 14 moves toward the first flat panel 10 to adhere to the first flat panel 10. The reason is that when the point particle 14 is located in the first area B1, a negatively induced charge is generated due to the existence of the point particle 14, and thus, a gravitational force between the point particle 14 and the negatively induced charge is stronger than repulsive force between the point particle 14 and an electric field generated between the first and second flat panels 10 and 12 according to the application of power by the power source 16. On the other hand, in the second area B2, the repulsive force between the electric field and the point particle 14 is stronger than the gravitational force between the point particle 14 and the negatively induced charge. Accordingly, when the point particle 14 is located in the second area B2, the point particle 14 moves toward the second flat panel 12 to adhere to the second flat panel 12, as shown in FIG. 1A.

When the point particle 14 is negatively charged instead of being positively charged, that is, when the point particle 14 is an electron, movement of the point particle 14 according to the location of the point particle 14 is opposite to a case when the point particle 14 is positively charged.

When the point particle 14 of FIG. 1 is a particle having an internal structure of, for example, a nanoparticle, the movement of the nanoparticle is changed. FIGS. 2A to 2C show movement of a positively charged nanoparticle 30 that is located between the first and second flat panels 10 and 12.

In FIGS. 2A to 2C, an area between the first and second flat panels 10 and 12 is divided into first to third areas C1 to C3. A first boundary 20 between the first area C1 and the second area C2 is spaced apart from the first flat panel 10 at a first length L11. A second boundary 22 between the second area C2 and the third area C3 is located between the first boundary 20 and the second flat panel 12 and is spaced apart from the first boundary 20 at a second length L22.

FIG. 2A shows movement of the positively charged nanoparticle 30 at an early stage. Reference numeral E1 denotes an electric field generated between the first and second flat panels 10 and 12 due to application of power by the power source 16. Also, a mark '+' shown in the middle of the nanoparticle 30 is an artificial charge, for example, a charge that is charged due to application of an additional voltage. Positive charges (+) and negative charges (-) distributed under a surface of the nanoparticle 30 are induced by the electric field E1 and are depolarization charges. Thus, the electric field E1 may be offset inside the nanoparticle 30 due to the depolarization charges. From among the depolarization charges, the positive charges are distributed on the surface of the nanoparticle 30 that faces the second flat panel 12 having a relatively low voltage, and the negative charges are distributed on the surface of the nanoparticle 30 that faces the first flat panel 10 having a relatively high voltage.

Referring to FIG. 2A, the nanoparticle 30 located in the third area C3 moves toward the second flat panel 12 by the electric field E1 between the first and second flat panels 10 and 12 to adhere to the second flat panel 12. When the positively charged nanoparticle 30 is located between the first and second flat panels 10 and 12, negative charges (-) are induced in the first and second flat panels 10 and 12 by the charges charged in the nanoparticle 30. When the charges charged in the nanoparticle 30 are negative charges, positive charges are induced in the first and second flat panels 10 and 12.

As shown in FIG. 2B, the nanoparticle 30 may be located in the second area C2 at an early stage. The second area C2 is an area corresponding to the first area B1 of FIG. 1A. In the second area C2, a strong gravitational force is applied between the charges charged in the middle of the nanoparticle 30 and negative charges (-) induced in the first flat panel 10 by the charges charged in the middle of the nanoparticle 30. The gravitational force is proportional to 1/r² , wherein 'r' denotes a distance between the first flat panel 10 and the nanoparticle 30. Even though the nanoparticle 30 located in the second area C2 is in the electric field E1, the nanoparticle 30 moves toward the first flat panel 10 instead of the second flat panel 12, that is, in a direction opposite to the electric field E1. When the nanoparticle 30 is located in the first area C1, as shown in FIG. 2C, a strong repulsive force (hereinafter, referred to as a first repulsive force) is applied between negative charges (-) induced in the first flat panel 10 and negative charges induced in the surface of the nanoparticle 30. The first repulsive force is proportional to 1/r³. Thus, in the first area C1, as a distance between the nanoparticle 30 and the first flat panel 10 is decreased, the first repulsive force is sharply increased. Accordingly, the nanoparticle 30 may not contact the first flat panel 10, and thus, the nanoparticle 30 moves away from the first flat panel 10 and moves toward the second area C2. In the second area C2, since the gravitational force is strong, the nanoparticle 30 moves toward the third area C3. Consequently, the nanoparticle 30 vibrates by moving between the first area C1 and the second area C2. The charges induced in the surface of the nanoparticle 30 are due to the electric field E1, a magnitude of the electric field E1 is proportional to a potential difference between the first and second flat panels 10 and 12, and the potential difference is due to the power source 16. Thus, by adjusting a DC voltage applied between the first and second flat panels 10 and 12, contact between the nanoparticle 30 and the first flat panel 10 may be prevented and controlled, which shows that the contact between the first and second flat panels 10 and 12 may be prevented and controlled by simply applying the DC voltage between the first and second flat panels 10 and 12. For example, friction between the first and second flat panels 10 and 12 may be prevented and a degree of contact may be controlled by maintaining a distance H1 between the first and second flat panels 10 and 12 that is equal to or less than the sum (L11+L22) of the first length L11 and the second length L22 when the nanoparticle 30 adheres to the surface of the second flat panel 12.

The nanoparticle 30 is coated with an insulating material to maintain a charge distribution of the nanoparticle 30. The coating of the nanoparticle 30 may use any of various methods.

Hereinafter, an apparatus with a friction preventing function according to embodiments of the present invention using the above-described principle will be described.

FIG. 3 is a cross-sectional view of a nanoparticle 40 used in an apparatus with a friction preventing function, according to an embodiment of the present invention. The nanoparticle 40 includes a conductive core 40a and a shell 40b surrounding the core 40a. The shell 40b may be, for example, aluminum oxide or silicon oxide. The shell 40b protects charges (+) charged inside the core 40a and depolarization charges (+, -) on a surface of the core 40a. Thus, a thickness of the shell 40b may be set to be proper for the protective function of the shell 40b. The thickness of the shell 40b may be uniform at a circumference of the core 40a. The core 40a may correspond to the nanoparticle 30 described with reference to FIGS. 2A to 2C. The core 40a may be, for example, a nano-sized aluminum (Al) particle. As in the case with the nanoparticle 40, a 'nanoparticle' described below refers to a particle having a diameter in a range between several nm and several hundreds of nm. For convenience of illustration and description, the nanoparticle 40 is shown as one circle.

FIG. 4 shows an apparatus (hereinafter, referred to as a first apparatus) with a friction preventing function according to an embodiment of the present invention.

Referring to FIG. 4, the first apparatus includes an axis 44 with a predetermined diameter in its center. The first apparatus includes a cylindrical structure 42 surrounding the axis 44. The cylindrical structure 42 is parallel to the axis 44. The cylindrical structure 42 and the axis 44 are conductors and spaced apart from each other. A gap between the cylindrical structure 42 and the axis 44 may be uniform at a circumference of the axis 44. The gap may be less than the sum (L11+L22) of the first length L11 and the second length L22 described with reference to FIGS. 2A to 2C. Conditions of the gap may be applied to another apparatus to be described below. The cylindrical structure 42 may be a rotating body that rotates around the axis 44. On the contrary, the cylindrical structure 42 may be fixed, and the axis 44 may rotate. A rotational axis of the cylindrical structure 42 may be the same as the center of the axis 44. The cylindrical structure 42 may be a rotating body that rotates around the center of the axis 44 or may be an object that moves along the axis 44. Materials of the cylindrical structure 42 and the axis 44 may be similar to or the same as those of a rotating body and its axis used in a general mechanical apparatus. A plurality of nanoparticles 40 are disposed between the axis 44 and the cylindrical structure 42. The nanoparticles 40 are uniformly distributed on an outer circumferential surface of the axis 44. The axis 44 is connected to a positive electrode (terminal) of a power source 48, and the cylindrical structure 42 is connected to a negative electrode (terminal) of the power source 48. The power source 48 may be a DC voltage source. The principle described with reference to FIGS. 2A to 2C applies to each nanoparticle 40. Thus, since the cylindrical structure 42 and the axis 44 do not contact each other in the first apparatus, friction between the cylindrical structure 42 and the axis 44 may be prevented. As such, since friction may be simply prevented by using the nanoparticle 40 and applying the DC voltage, there is no need to use oil or grease that is conventionally used. In this regard, the first apparatus may be eco-friendly, and this may apply to another apparatus to be described. Also, since a current is not directly applied to prevent friction, high efficiency may be maintained, and also even though a general battery is used, the apparatus may be used for long hours.

Although not shown in the drawing, the nanoparticles 40 may be uniformly distributed on an inner circumferential surface of the cylindrical structure 42 instead of an outer circumferential surface of the axis 44. When the nanoparticles 40 are distributed on the inner circumferential surface of the cylindrical structure 42, the cylindrical structure 42 and the axis 44 are connected to each other with respect to the power source 48 in a way opposite to that shown in FIG. 4. Also, even when charges charged in the middle of the nanoparticles 40 are negative charges instead of positive charges, the cylindrical structure 42 and the axis 44 are connected to each other with respect to the power source 48 in a way opposite to that shown in FIG. 4.

On the other hand, even though the nanoparticles 40 are uniformly distributed entirely on the outer circumferential surface of the axis 44, the nanoparticles 40 may be distributed only on a part of the outer circumferential surface of the axis 44, as shown in FIG. 5. In FIG. 5, the DC voltage applied to the axis 44 and the cylindrical structure 42 may be increased compared to that in the case of FIG. 4.

FIG. 6 shows an apparatus (hereinafter, referred to as a second apparatus) with a friction preventing function according to another embodiment of the present invention.

Referring to FIG. 6, the second apparatus includes a fixed first object 50 and a second object 52 that is movable along the first object 50. The first object 50 and the second object 52 are conductors that are spaced apart from each other. The first and second objects 50 and 52 may or may not entirely be conductors. For example, portions of the first and second objects 50 and 52 that face each other may be conductors, and the remaining portions of the first and second objects 50 and 52 may not be conductors. The first object 50 may be a linear rail. A cross-section of the first object 50 may have a rectangular shape, or alternatively, the cross-section of the first object 50 may have a semicircular shape or a triangular shape. A plurality of nanoparticles 40 may adhere to a surface of the first object 50 facing the second object 52. The nanoparticles 40 may be uniformly distributed entirely on the surface of the first object 50. Although the nanoparticles 40 are spaced apart from one another in FIG. 6, each nanoparticle 40 includes a shell 40b having an insulating property, as shown in FIG. 3, and thus, the nanoparticles 40 may contact one another. The second object 52 is formed to surround the surface of the first object 50 to which the nanoparticles 40 adhere. The second object 52 may be a part of a machine (for example, a vehicle or a train) that moves above the first object 50. An inner surface of the second object 52 may be deformed to correspond to a shape of the surface of the first object 50. The first and second objects 50 and 52 may be connected to a DC voltage power source 56. A positive electrode and a negative electrode of the power source 56 are connected to the second object 52 and the first object 50, respectively.

Although not shown in FIG. 6, the nanoparticles 40 may adhere to the inner surface of the second object 52 instead of the surface of the first object 50. Here, the connection of the power source 56 is performed in a way opposite to that shown in FIG. 6.

FIG. 7 shows an apparatus (hereinafter, referred to as a third apparatus) with a friction preventing function according to another embodiment of the present invention.

Referring to FIG. 7, the third apparatus includes a lower structure 80, an upper structure 82, and a plurality of nanoparticles 40. The lower structure 80 is fixed and may be a flat panel having a predetermined length. A top surface of the lower structure 80 may be flat. The nanoparticles 40 adhere to a top surface of the lower structure 80. The upper structure 82 may be an object that moves above the lower structure 80 or may be a carrier. For convenience of illustration, the upper structure 82 is shown as a flat panel in FIG. 7. Thus, a shape of the upper structure 82 may vary depending on the intended use. The lower and upper structures 80 and 82 may be conductors. The lower and upper structures 80 and 82 may entirely be conductors, or portions of the lower and upper structures 80 and 82 that are necessary for prevention of friction may be conductors. For example, in the case of the lower structure 80, a conductive layer may be disposed only on the top surface of the lower structure 80, and in the case of the upper structure 82, a conductive layer may be disposed only on a bottom surface of the upper structure 82. A DC voltage power source 86 is connected to the lower and upper structures 80 and 82. The lower structure 80 and the upper structure 82 are connected to a negative electrode terminal and a positive electrode terminal of the power source 86, respectively. When the power source 86 is in a connected state, the upper structure 82 is maintained in a non-contact state. That is, the upper structure 82 is disposed above the lower structure 80 without contacting the lower structure 80. In this state, if a force is horizontally applied to the upper structure 82, the upper structure 82 may be easily moved horizontally without friction against the lower structure 80. The nanoparticles 40 may adhere to the upper structure 82, which is a movable body, instead of being disposed in the lower structure 80. At this time, the connection of the power source 86 is performed in a way opposite to that shown in FIG. 7.

Although not shown in FIGS. 4 to 7, an adherent layer may be formed on a surface to which the nanoparticles 40 adhere, and the nanoparticles 40 may adhere to the adherent layer.

FIG. 8 show an apparatus (hereinafter, referred to as a fourth apparatus) with a friction preventing function according to another embodiment of the present invention.

Referring to FIG. 8, the fourth apparatus may be the same as the second apparatus described with reference to FIG. 6 except that a nano material film 60 is coated on a surface of the first object 50. FIG. 9 is an enlarged cross-sectional view of a region A1 including a part of the nano material film 60 of FIG. 8.

Referring to FIG. 9, the nano material film 60 includes a plurality of nanoparticles 40 and a material film 70 covering the nanoparticles 40. The material film 70 attaches the nanoparticles 40 to the first object 50 to fix the nanoparticles 40. The material film 70 may be an insulating material, and its surface may be flat. The material film 70 may be paint or paste. Thus, the nano material film 60 may be formed by mixing the nanoparticle 40 with paint or paste, kneading them, coating a resultant on a surface of the first object 50, and drying the resultant.

FIG. 10 shows a case where the nano material film 60 is coated on an outer circumferential surface of the axis 44 instead of the nanoparticles 40. In the apparatuses shown in FIGS. 5 and 7, the nano material film 60 may be provided instead of the nanoparticles 40. Even when the nano material film 60 is provided instead of the nanoparticles 40, the nano material film 60 may be coated on another surface facing the original surface instead of being coated on the original surface.

FIG. 11 shows an apparatus (hereinafter, referred to as a fifth apparatus) with a friction preventing function according to another embodiment of the present invention.

Referring to FIG. 11, the fifth apparatus includes a pipe 90 having a predetermined length and a movable body 92 that is released or launched through the pipe 90. The pipe 90 may be a metallic pipe or a nonmetallic pipe in which a conductive layer is coated on an inner surface. Also, the pipe 90 may be a gun barrel of a personal weapon or may be a cannon barrel of a cannon or a tank. If the pipe 90 is a gun barrel or a cannon barrel, the movable body 92 may be a launcher such as a bullet or a cannon ball. A DC power source 96 is connected to the pipe 90 and the movable body 92. A positive electrode terminal and a negative electrode terminal of the power source 96 are connected to the pipe 90 and the movable body 92, respectively. If the movable body 92 is a launcher, the movable body 92 is released out of the pipe 90, and simultaneously, the connection between the movable body 92 and the power source 96 is lost. A plurality of nanoparticles 40 may adhere to an inner surface of the pipe 90. At this time, the connection of the power source 96 is performed in an opposite way. Alternatively, the nano material film 60 may be provided instead of the nanoparticles 40.

Although the nanoparticles 40 of the above-described apparatuses are configured as a single-layered structure to adhere to a surface, a plurality of nanoparticles 40 may be configured as a multi-layered structure to adhere to a surface of an object 100 as shown in FIG. 12. Although FIG. 12 shows the nanoparticles 40 configured as a double-layered structure, the present invention is not limited thereto.

Hereinafter, a method of manufacturing apparatuses with a friction preventing function, according to embodiments of the present invention, will be described.

Referring to FIG. 13, a plurality of nanoparticles 40 adhere to a surface of a first object 110. A second object 120 is disposed to face the first object 110 across the nanoparticles 40. Next, a first voltage VH is applied between the first and second objects 110 and 120. Electrons are emitted from the nanoparticles 40 due to the application of the first voltage VH, and net charges of the nanoparticles 40 become positive charges (+). Accordingly, the nanoparticles 40 are positively charged (a state where positive charges are formed in the middle of the core 40a of FIG. 3). A degree of the emission of the electrons may be controlled by adjusting the first voltage VH.

Next, a second voltage VL is applied between the first and second objects 110 and 120, as shown in FIG. 14. The second voltage VL is applied to prevent friction, and charges (+, -) on the surface of the core 40a of FIG. 3 are induced by the second voltage VL. The second voltage VL may be lower than the first voltage VH. A gap between the first and second objects 110 and 120 may be maintained equal to or less than the sum (L11+L22) of the first length L11 and the second length L22 shown in FIGS. 2A to 2C before or at the time when the second voltage VL is applied.

As described above, the nanoparticles 40 may be charged after the nanoparticles 40 adhere onto the first object 110, or may be charged before the nanoparticles 40 adhere onto the first object 110. In other words, the charged nanoparticles 40 may adhere onto the first object 110. Also, the nano material film 60 described with reference to FIG. 8, instead of the nanoparticles 40, may be coated on the first object 110. The nano material film 60 may be charged in the same way as the nanoparticles 40.

It should be understood that the exemplary embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.

INDUSTRIAL APPLICABILITY

An apparatus with a friction preventing function according to an embodiment of the present invention may be applied to apparatuses (for example, various types of carrying apparatuses, shooting apparatuses, and projection apparatuses) which include an apparatus required to prevent friction and to adjust the degree of friction, for example, a rotation apparatus, and an apparatus in which linear motion or reciprocating linear motion of one component is performed.