KR20240012133A - Outer rotor type oilless air compressor - Google Patents

Abstract

The outer rotor type oilless air compressor is rotatable and includes a ring-shaped rotor with a plurality of magnets along the inner circumferential surface, a stator coil provided inside the rotor that provides electromagnetic force to rotate the rotor, and a stator coil connected to the rotor. A motor shaft that rotates as one unit, a flywheel that is coupled to one side of the motor shaft to provide rotational inertia, an eccentric cam that is coupled to the other side of the motor shaft and rotates so that it is eccentric with respect to the center of rotation, and the eccentric cam and the main A cylinder that is rotatably connected through a bearing, has a connecting rod with a piston on the other side, the piston reciprocates in the inner space, and has an intake port and an exhaust port to intake and exhaust external air into the inner space. , and a valve assembly that selectively opens and closes the intake passage and the exhaust passage.

Description

Outer rotor type oilless air compressor {Outer rotor type oilless air compressor}

The following description relates to an outer rotor type oil-less air compressor.

An air compressor is a device that compresses air to produce high pneumatic pressure. Among them, an oilless air compressor refers to a reciprocating air compressor that does not require lubrication. Because there is no oil mixed in the air, there is no need for oil management, and it is highly portable, making it suitable for use while moving.

The air compressor sucks the surrounding air into the cylinder provided inside, and then compresses the air sucked into the cylinder through piston action. It can also be used as an inhaler because it sucks in the surrounding air, and uses the produced compressed air. By connecting it to air tools (e.g., air guns, spray guns, airbrushes, etc.), it can be used for various purposes such as industrial, medical, and household devices that use compressed air.

Figures 1 and 2 are presented for detailed explanation. Figure 1 is a cross-sectional view showing the air intake of an air compressor, and Figure 2 is a cross-sectional view showing the air discharge of the air compressor. The shaft 70, which is connected to a motor (not shown) and rotates, is inserted and coupled to the eccentric hole 11 formed in the eccentric body 10. The eccentric body 10 is connected to the connecting rod 30, and a bearing 20 is installed between it to rotatably couple the eccentric body 10 to the connecting rod 30. The piston 25 coupled to one end of the connecting rod 30 by the rotation of the eccentric body 10 reciprocates in the inner space 45 of the cylinder 40, and moves the inner space 45 of the cylinder 40. ) is formed with an intake passage 64 and an exhaust passage 63 communicating to the outside, and each of them is equipped with an intake valve 62 and an exhaust valve 61.

When the eccentric body 10 rotates and the piston 25 moves downward in the inner space 45 of the cylinder 40, the intake valve 62 opens the intake passage 64 and the exhaust valve 61 opens. When the exhaust passage 63 is closed, the internal space 45 expands and the pressure drops, causing external air to flow into the internal space 45 of the cylinder 40 through the suction passage 64. This operation can also be used as a vacuum pump to suck in external air. Next, the eccentric body 10 is rotated in a state in which the intake path 64 and the exhaust path 63 are closed using the intake valve 62 and the exhaust valve 61, so that the piston 25 moves into the cylinder 40. When advancing in the direction of reducing the internal space 45, the air sucked into the internal space 45 is compressed. After compression occurs for a certain period of time, when the exhaust valve 61 is opened, the compressed air is provided to the outside through the exhaust passage 63. A piston ring 50 is coupled to the outer peripheral surface of the piston 25 to prevent compressed air in the internal space 45 from leaking.

For example, when an oil-less air compressor has a problem, there are cases where the motor does not have sufficient torque and does not perform as well as desired. In addition, if the torque of the motor is insufficient and overheating occurs during operation, the coil of the motor is locally heated and the insulation is destroyed and burned out. This not only causes the compressor to fail, but also poses a risk of fire.

In this case, a motor that provides large torque can be used, but there is a problem that the size and weight increase and the unit price increases. In order to increase the torque, the outer diameter and length of the motor must be increased, but this is not a correct solution due to the problem that the size of the compressor must also be increased. Therefore, if there is no room for motor torque, the performance of the compressor is lowered before use.

The purpose of the embodiment is to provide an outer rotor type oilless air compressor that can be compact and provide sufficient torque.

The purpose of the embodiment is to provide an outer rotor type oilless air compressor in which noise and vibration are suppressed and the risk of failure, such as the risk of burnout, is significantly reduced.

The problems to be solved in the embodiments are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to embodiments for achieving the above-described problem, the outer rotor type oilless air compressor includes a ring-shaped rotor that is rotatable and has a plurality of magnets along the inner circumferential surface, and is provided inside the rotor, A stator coil that provides electromagnetic force so that the rotor rotates, a motor shaft that is connected to the rotor and rotates as one piece, a flywheel that is coupled to one side of the motor shaft to provide rotational inertia, and a flywheel that is coupled to the other side of the motor shaft to rotate, An eccentric cam coupled to be eccentric with respect to the rotation center, a connecting rod connected to the eccentric cam and the main bearing so that it can rotate, and with a piston coupled to the other side, the piston reciprocates in the internal space, and the intake and exhaust passages are connected to each other. It includes a cylinder formed to intake and exhaust external air into the internal space, and a valve assembly that selectively opens and closes the intake port flow path and the exhaust port flow path.

The main bearing has an insert ring made of a different metal material connected to the outer surface by interference fit. The insert ring is preferably manufactured by die casting, and the insert ring is preferably connected to the defect groove and engaging protrusion formed on the connecting rod by interference fit. .

Additionally, a shock absorbing bearing and a shaft bearing may be provided in the direction from the main bearing to the rotor, respectively.

According to embodiments, there is an effect of being able to provide sufficient torque while being compact.

In addition, while noise and vibration are suppressed, the risk of breakdown, such as the risk of burnout, can be significantly reduced.

The effects according to the embodiment are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below.

Figure 1 is a cross-sectional view showing the air intake of an air compressor.
Figure 2 is a cross-sectional view showing air discharge from an air compressor.
Figure 3 is a cross-sectional perspective view of an oil-less air compressor according to an embodiment of the present invention.
Figure 4 is a cross-sectional view of an oil-less air compressor according to an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. However, various changes can be made to the embodiments, so the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents, or substitutes for the embodiments are included in the scope of rights.

The terms used in the examples are for descriptive purposes only and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the embodiments belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

In addition, when describing with reference to the accompanying drawings, identical components will be assigned the same reference numerals regardless of the reference numerals, and duplicate descriptions thereof will be omitted. In describing the embodiments, if it is determined that detailed descriptions of related known technologies may unnecessarily obscure the gist of the embodiments, the detailed descriptions are omitted.

Additionally, in describing the components of the embodiment, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being "connected," "coupled," or "connected" to another component, that component may be directly connected or connected to that other component, but there is no need for another component between each component. It should be understood that may be “connected,” “combined,” or “connected.”

Components included in one embodiment and components including common functions will be described using the same names in other embodiments. Unless stated to the contrary, the description given in one embodiment may be applied to other embodiments, and detailed description will be omitted to the extent of overlap.

3 and 4, the structure and operation of the oil-less air compressor according to the present invention will be described. Figure 3 is a cross-sectional perspective view of an oil-less air compressor according to an embodiment of the present invention, and Figure 4 is a cross-sectional view of an oil-less air compressor according to an embodiment of the present invention.

The oil-less air compressor 1000 is equipped with a drive motor 600 inside. The drive motor 600 is broadly classified into a rotatable rotor 615 and a stator 620 provided therein. The rotor 615 has a ring shape, and a plurality of magnets 610 are regularly arranged along its inner peripheral surface, and a stator coil 625 for providing electromagnetic force is provided at a position corresponding to the magnets 610. Since the rotation principle of the motor is a widely known technology, detailed explanation will be omitted. The rotor 615 is coupled to the motor shaft 70, so the rotation of the rotor 615 rotates the motor shaft 70, and the motor shaft 70 is coupled to the flywheel 640, which provides rotational inertia. there is.

The motor shaft 70 is connected to the eccentric cam 100 and is inserted into the eccentric hole 120 provided in the cam body 110 of the eccentric cam 100. When the motor shaft 70 rotates, the eccentric cam 100 rotates. At this time, the eccentric cam 100 is coupled to the motor shaft 70 so that it is eccentric with respect to the rotation center. The eccentric cam 100 is coupled to the connecting rod 210 through the main bearing 310, and the other side of the connecting rod 210 is combined with the piston 250 and inserted into the internal space 450 of the cylinder 400. do. The cylinder 400 has a cylindrical shape with an internal space 450, and the connecting rod 210 and the piston 250 coupled thereto reciprocate within the internal space 450. That is, by the connecting rod 210 connected to the eccentric cam 100 to enable relative movement, the rotational force produced by the drive motor 600 is transformed into a reciprocating motion that can compress or expand the inner space of the cylinder 450. It will happen.

The internal space 450 of the cylinder is communicated with the outside through an intake passage 510 and an exhaust passage 520, and a valve assembly 500 that selectively opens and closes the intake passage and exhaust passages 510 and 520 is coupled. there is.

When the eccentric cam 100 rotates and the piston 250 moves downward in the internal space 450 of the cylinder 400, the intake passage 510 is opened using the valve in the valve assembly 500 and the exhaust passage is opened. When 520 is closed, the internal space 450 expands, the pressure drops, and external air flows into the internal space 450 of the cylinder 400 through the intake passage 510. This operation can also be used as a vacuum pump to suck in external air. Next, when the eccentric cam 100 is rotated with the intake passage 510 and the exhaust passage 520 closed, the piston 250 moves forward in a direction that reduces the internal space 450 of the cylinder 400, The air sucked into the internal space 450 is compressed. After compression occurs for a certain period of time, when the exhaust passage 520 is opened, the compressed air is provided to the outside. A piston ring may be coupled to the outer peripheral surface of the piston 250 to prevent compressed air in the internal space 450 from leaking.

At this time, the eccentric cam 100 is coupled to the connecting rod 210 through the main bearing 310, and if the distance (L) between the connecting rod 210 and the drive motor 600 becomes long, it may cause vibration and noise. Therefore, in order to support the motor shaft 70 in the meantime, a shock absorbing bearing 321 and a shaft are installed at positions spaced a certain distance (L1, L2) away from the main bearing 310 in the direction of the drive motor 600, respectively. Install bearing (322). Here, the sizes have the relationship L > L2 > L1. It is desirable to place the rod bearing adjacent to the shock-absorbing auxiliary bearing to minimize the separation distance (L1) between the connecting rod 210 and the shock-absorbing auxiliary bearing 321.

In addition, the main bearing 320 is coupled to the outer surface with an insert ring 240 made of a different metal material in an interference fit manner. The insert ring 240 is manufactured by die casting, and is press-fitted with the engaging protrusion 241 formed in the engaging groove 242 formed in the connecting rod 210. Instead of manufacturing the shock absorbing bearing 321 or the shaft bearing 322 using the interference fitting method, the main bearing 310 is manufactured by die casting the insert ring 240 and connecting rod 210 joined by the interference fitting method. By using it, the noise and vibration of the outer rotor type can be effectively suppressed.

With this configuration, not only can the compressor be configured as an outer rotor type that can provide sufficient torque without having to be large in size, but it is also possible to provide a compressor that is resistant to noise and vibration.

Although the embodiments have been described with limited drawings as described above, those skilled in the art can apply various technical modifications and variations based on the above. For example, the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or other components are used. Alternatively, appropriate results may be achieved even if substituted or substituted by an equivalent.

Therefore, other implementations, other embodiments, and equivalents of the claims also fall within the scope of the following claims.

10: Eccentric body 11: Eccentric hole
20: bearing 25, 250: piston
30, 210: connecting rod 40, 400: cylinder
45, 450: Cylinder inner space 50: Piston ring
61: exhaust valve 62: intake valve
63: exhaust passage 64: intake passage
70: Motor shaft 100: Eccentric cam
110: Cambody 120: Eccentric hole
310: main bearing 321: bearing for shock absorption
500: valve assembly 510: intake passage
520: exhaust port 600: drive motor
610: Magnetic 615: Rotor
620: stator 625: stator coil
640: flywheel

Claims (4)

A ring-shaped rotor that is rotatable and has a plurality of magnets along its inner circumferential surface;
a stator coil provided inside the rotor and providing electromagnetic force to rotate the rotor;
A motor shaft connected to the rotor and rotating integrally with it;
A flywheel coupled to one side of the motor shaft to provide rotational inertia;
An eccentric cam coupled to the other side of the motor shaft to rotate and to be eccentric with respect to the center of rotation;
a connecting rod rotatably connected to the eccentric cam and the main bearing and having a piston coupled to the other side;
a cylinder in which the piston reciprocates in an internal space and has an intake channel and an exhaust channel to intake and exhaust external air into the internal space;
A valve assembly that selectively opens and closes the intake and exhaust passages;
Outer rotor type oil-less air compressor including.
According to paragraph 1,
An outer rotor type oilless air compressor, wherein an insert ring made of a different metal material is coupled to the outer surface of the main bearing in an interference fit manner, and the insert ring is manufactured by die casting.
According to paragraph 2,
An outer rotor type oilless air compressor, characterized in that the insert ring is press-fitted with a defect groove and a coupling protrusion formed on the connecting rod.
According to paragraph 1,
An outer rotor type oilless air compressor, characterized in that a shock absorbing bearing and a shaft bearing are provided in the direction from the main bearing to the rotor.

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