KR20230053224A - cocentric air motor - Google Patents

Abstract

A case having a cylindrical inner space, a rotation center shaft that is hollow with the rotation center axis of the case, and a rotor that is installed in the case and has a diameter matching the inner diameter of the case and rotates around the rotation center axis in the case, Both ends in the direction of the central axis are closed by a closing plate, and when viewed from one side in the direction of the central axis, at least one air inlet and air outlet are arranged on a circumference smaller than the circumference formed by the inner diameter surface of the case in at least one of the closing plates. And, a long groove is formed in the direction of the rotation center on the side surface of the rotor so as to overlap the air inlet and the air outlet, and on one side viewed in the direction of the central axis, at least some of the grooves are sequentially formed at the air inlet and air as the rotor rotates. An air core type pneumatic motor that is formed to overlap the outlet and has a movable piece installed on the inner diameter surface of the case so that the groove meets the groove first before overlapping with the air inlet in the rotational direction, and the degree of protrusion can be changed while contacting the rotor side surface. is initiated.

Description

Air core type pneumatic motor {cocentric air motor}

The present invention relates to a pneumatic motor, and more particularly, to a pneumatic motor that rotates a rotor using compressed air and extracts rotational power from the rotating rotor.

A device for extracting power using pneumatic pressure has a configuration similar to that of an internal combustion engine, and supplies compressed air to a cylinder to reciprocate a piston in the cylinder while rotating a crankshaft connected to the piston and a connecting rod, a pneumatic engine, and a rotor. A pneumatic motor in which air pressure or impulsive force is applied to one side of pins (wings) installed on a side wall so that a rotor rotates around a rotation axis may be used.

As the pneumatic motor, one using a rotor having an asymmetrical element such as a vane motor and one using a symmetrical rotor in the form of a turbine may be mentioned.

In vane motors, the position of the vane changes, and the vane comes into contact with the inner wall of the case to create a sealed space in which air is difficult to leak, and to use the energy of the compressed air supplied between the case and the rotor to the maximum while reducing loss due to air leakage. There is an advantage.

1 is a cross-sectional view showing a cross section cut by a plane perpendicular to the rotor rotational axis direction to explain the principle of operation of a conventional vane motor.

Here, a rotating rotor is installed in the casing 211, and a portion of the casing 211 has a fluid inlet 253 through which fluid applying pressure flows in and a fluid outlet 255 through which fluid is discharged. When the pressure fluid is introduced into the fluid inlet 253, the fluid pressure extends to the outside of the rotor and acts on the vanes 235 whose extending length is variable. Accordingly, while the vane 235 moves in the pressure direction, the entire rotor rotates within the casing 211 . When the fluid that transmits the pressure to the vane 235 reaches the fluid outlet 255 of the case, it is discharged through the fluid outlet 255 having a low pressure.

That is, when the pressure fluid entering the fluid inlet encounters a fluid outlet having a low pressure, it exits through the fluid outlet and applies pressure to the vanes 235 in the process to rotate the rotor.

At this time, the vane 235 is coupled to the rotor body 231, and the length of the vane 235 protruding from the body 231 may be variable. To this end, the vane 235 is inserted into the groove 231a of the rotor body 231 and may move in the longitudinal direction of the groove 231a. Since the distance between the inner wall surface of the casing 211 and the rotating shaft 233 of the rotor body 231 is different depending on the position of the inner wall surface of the casing, in a place where the distance is wide, a large portion of the vane 235 is the groove of the body 231 ( 231a), the protruding length of the vane 235 increases, and most of the vane is inserted into the main body groove where the gap is narrow, so the protruding length of the vane decreases.

In order for the vane 235 to smoothly enter and exit the groove 231a of the main body 231, an elastic body such as a spring may be included at the bottom of the groove between the vane and the vane 235. Alternatively, a separate spring may not be installed because the vane may come out of the groove by the rotational centrifugal force of the rotor.

In a section where the gap between the rotor body 231 and the inner wall surface is narrowed, when the rotor body 231 rotates, the end of the vane 235 comes into contact with the inner wall surface and receives pressure to be inserted into the groove 231a.

However, in the conventional vane motor, if the gap between the end of the vane 235 and the inner wall surface of the casing 211 is too large, fluid escapes through this gap, resulting in a loss of pressure, and if the gap is too small, between the vane and the inner wall surface of the casing. There is a problem in that a significant amount of energy due to fluid pressure is lost due to friction due to severe friction and the cost of replacement and maintenance increases due to wear of the vane and inner wall surface. Since these problems have a trade-off relationship with each other and cannot be completely solved in existing vane motors, the most efficient and durable You need to determine the appropriate gap size.

However, in such a vane motor, even when the appropriate size and air pressure of these elements are determined, there is rotational instability due to the asymmetrical elements of the rotor such as the aforementioned vane configuration and the resulting reduction in efficiency, and the vane is too far in the groove. There is a problem in that if it is allowed to come out far, it may be completely separated, or vibration or other unstable conditions may be achieved while the vane rubs against the inner wall surface of the casing.

In addition, the vane protrudes appropriately from the groove as the rotor rotates, adheres to the inner diameter surface of the case containing the rotor, and must be properly inserted into the groove. It cannot be displaced and may deviate from the correct position, reducing the efficiency of the pneumatic motor.

Therefore, it would be desirable to have a pneumatic motor configured to solve the disadvantages of the vane motor while using the advantages of the vane motor.

Korean Registered Patent No. 10-1874583: Vane Motor

An object of the present invention is to provide a pneumatic motor having a configuration capable of reducing the disadvantages of the vane motor while using the above-described advantages of the vane motor.

The air-core pneumatic motor of the present invention for achieving the above object,

A case having a cylindrical inner space and a central axis of rotation that is hollow with the central axis of rotation of the case, and is installed in the case so that its diameter matches the inner diameter of the case and rotates around the central axis of rotation in the case. With a cylindrical rotor,

Both ends of the case in the direction of the central axis are closed by a closing plate,

When viewed from one side in the direction of the central axis, at least one air inlet and one or more air outlets of the closing plate are arranged on a circumference smaller than the circumference formed by the inner diameter surface of the case, respectively, and the air inlet and the air outlet A groove is formed on the side surface of the rotor so as to overlap in a direction toward the rotation center,

In a cross section perpendicular to the central axis or one side viewed in the direction of the central axis, at least a portion of the groove is formed to overlap the air inlet and the air outlet in turn as the rotor rotates,

A movable piece capable of changing the degree of protrusion while contacting the side surface of the rotor is installed on the inner diameter surface of the case so that the groove meets the groove first before overlapping with the air inlet based on the rotational direction, so that the rotor rotates while the rotor rotates. The groove may be formed so that the movable piece, the air inlet, and the air outlet meet in order.

At this time, in the aspect of the present invention viewed in the direction of the central axis, the groove has a deep groove portion in the front relative to the rotational direction of the rotor, and a gap (width) between the side surface of the rotor and the inner diameter surface of the case behind the deep groove portion. ) is connected to the small tail part compared to the deep groove part, and the attachment of the movable piece in the tail part (the part that protrudes most from the inner diameter surface) continuously touches the side surface of the rotor to open the front space in front of it and the rear space behind it. It may be made to serve as a check valve that prevents air in the front space from going to the rear space while dividing it.

In this case, in one aspect viewed in the direction of the central axis, the tail portion may always be made such that it does not overlap with the air outlet and the air inlet and spatially does not communicate with each other.

In the present invention, the movable piece may be made in the form of a spring hinge (hinge) in which a spring is installed on the hinge shaft portion, or configured to form an air spring to receive force directed toward the side surface of the rotor.

In the present invention, in order to prevent excessive movement of the movable piece to generate vibration or noise when the movable piece meets the deep groove portion, when viewed from one side, a bridge connecting the front and rear entrances of the deep groove portion in the rotational direction of the rotor. At least one (guide part) may be installed, and at this time, the bridge is formed to enable air exchange between the space of the deep groove part and the space of the tail part, and air exchange between the groove, the air inlet, and the air outlet, respectively.

In the present invention, based on the rotation direction of the rotor, the movable piece, the air inlet, and the air outlet are located in order, the number of installation combinations of the movable piece, the air inlet, and the air outlet is more than one, and the installation intervals between the combinations are equal intervals And, the mutual distance between the movable piece, the air inlet, and the air outlet in the combination may be made to be the same over all the combinations.

In the present invention, the number of grooves and the number of movable pieces, air inlets, and air outlet combinations are different, and the installation intervals of the grooves and the installation intervals of the combinations may be equally spaced.

At this time, regardless of the rotational displacement of the rotor, if at least one of the grooves is connected spatially to any air inlet in the front space, it is preferable because it is convenient for starting.

According to the present invention, while using the advantages of preventing leakage of compressed air due to the formation of an enclosed space in a vane motor, which is one of the existing pneumatic motors, and using the resulting compressed air pressure sufficiently, on the other hand, the vane and Disadvantages of improper movement of the vane due to friction between the grooves and reduction in efficiency due to friction between the vane and the inner diameter surface of the case can be reduced.

1 is a cross-sectional view showing the configuration of one example of a conventional vane motor;
Figure 2 is an exploded perspective view showing a configuration according to an embodiment of the air-core type pneumatic motor of the present invention;
Figure 3 is a perspective view of an assembled state of the air-core pneumatic motor of Figure 2;
Figure 4 is a perspective view showing a state in which one side plate is removed from Figure 3;
Figure 5 is a perspective view showing a state in which one side plate and case are removed from the air-core pneumatic motor of the present invention similar to that of Figure 2, but a movable piece coupled to the case is left;
6 to 9 are perspective side views of the air-core pneumatic motor of FIG. 3 viewed from one side in the same direction as the rotor rotation center axis, showing states in which the rotor rotates and is in another rotational displacement;
Figure 10 is a side view of the embodiment of the present invention as shown in Figure 5, viewed from one side in the same direction as the direction of the center axis of rotation of the rotor in a state in which one side of the finishing plate is removed.
11 to 14 are examples different from those of FIGS. 2 and 5, each having a different number of movable pieces and grooves, viewed from one side in the same direction as the direction of the central axis of rotation of the rotor, with the closing plate removed from one side. They are side views.

Hereinafter, the present invention will be described in more detail through specific embodiments of the present invention with reference to the drawings.

Referring to FIGS. 2 to 4, an air-core pneumatic motor constituting the first embodiment of the present invention will be described.

First, this embodiment has a case 11 having a cylindrical inner space, and a rotational center axis that is hollow with the rotational center axis of the case 11, and is installed in the case 11 so that the diameter is substantially the same as the inner diameter of the case. It has a cylindrical (including cylindrical) rotor 31 or rotor that rotates around the rotation center axis 33 in the case. Both ends of the case 11 in the direction of the central axis are closed by the closing plate 13 .

From one side viewed in the direction of the central axis, each of the two end plates 13 has an arc-shaped air inlet 135) having a substantially constant width along the air core circumference smaller than the circumference formed by the inner diameter surface 14 of the case 11 4 The dog and four air outlets 133 are alternately arranged. When viewed from the far side, a groove 31a is provided on the side surface of the rotor to partially overlap the air inlet 135 and the air outlet 133. Here, the groove is formed in an approximate V-shape, and the distance (width) between the rotor side surface and the inner diameter surface of the case is smaller than the depth of the groove and the rotational direction (rear ) and has a tail portion 311a extending long. Here, the distance between the side surface of the rotor 31 and the inner diameter surface 14 in the tail portion 311a gradually decreases as it goes backward in the rotational direction.

In addition, the groove 31a is formed long in the direction of the central axis over the entire length of the rotor, and overlaps the air inlet 135 and the air outlet 133 only in the deep groove portion and does not overlap in the tail portion 311a. When the groove 31a overlaps the air inlet, compressed air is introduced into the groove through the air inlet, and when the groove 31a overlaps the air outlet, the compressed air of the groove can be discharged to the outside under a lower air pressure.

Likewise, when viewed from this side, a case groove 15 is formed on the inner diameter surface 14 of the case so that the groove 31a first meets the groove 31a at a position before overlapping with the air inlet 135 in the rotational direction, , the movable piece 17 is installed in the case groove 15. Here, the movable piece 17 is formed in the form of a spring hinge and coupled to the hinge pin of the case body. Even if the rotational displacement or protrusion of the hinge shaft center of the movable piece 17 changes, the case groove 15 is the rotating end of the movable piece 17 so that air does not communicate with the groove 31a formed on the side surface of the rotor 31 It is possible to move relative to the surface of the case groove 15, but not to form a large gap.

Therefore, usually, the movable piece (the most protruding part of the inner diameter surface among the movable pieces) comes into contact with the side surface of the rotor 31, except for the deep groove part, and is between the inner diameter surface 14 and the side surface of the rotor 31. The degree of protrusion from the inner diameter surface may vary according to the interval of the . The change in the degree of protrusion can be thought of as corresponding to the change in the protruding width of the bale from the vane groove in the vane motor.

On the other hand, the inlet of the V-shaped deep groove is rounded, and the most protruding part of the movable piece 17 and in contact with the side surface of the rotor 31 is also rounded to reduce friction due to the shape during rotation of the rotor. It can be. Oil film formation or coating treatment to reduce friction is also possible.

In addition, as the rotor 31 rotates in the rotation section where the movable piece 17 meets the groove 31a, the groove is divided into two spaces by the movable piece 17. For the two spaces separated by the movable piece, the movable piece 17 serves as a kind of check valve. That is, when the front space overlaps the air inlet 135, the compressed air in the front space is prevented from moving to the rear space, while the volume of the rear space is reduced according to the rotation of the rotor, and the air is compressed in the rear space so that the front When it has a greater pressure than the space, the compressed air is configured to move to the front space by a pressure difference.

The role of such a check valve is, for example, to adjust the inclined or convex curved shape of the front part and the inclined or concave curved shape of the rear part based on the rotational direction of the tip part where the movable piece contacts the rotor side surface, and to adjust the elasticity of the hinge spring or air spring. It can be combined and adjusted.

On the other hand, Figure 5 is a perspective view showing a state in which one side plate and case are removed from the air-core type pneumatic motor constituting the second embodiment of the present invention similar to that of Figure 2, but the movable piece 17 coupled to the case is left.

Unlike the first embodiment of FIG. 2, bridges 31b are formed at both ends of the rotor in the longitudinal direction of the rotor to connect both entrances of the deep groove in the rotational direction. This bridge (31b) greatly protrudes when the movable piece 17 meets the deep groove portion and suddenly falls into the deep groove, causing vibration and noise and reducing the risk of partially intensifying friction or damaging the movable piece parts. can do.

Here, two bridges 31b are formed, but one such bridge may be formed according to the embodiment, or a plurality of bridges may be formed at appropriate intervals in the length direction of the rotor. In either case, the bridge communicates air in the groove, It is preferable to form so as not to interfere with the spatial connection between the air inlet and the air outlet.

When the rotor rotates in the rotation direction in the configuration of the above embodiments, the groove 31a of the rotor 31 first passes through the movable piece 17, then meets the air inlet 135, and then the air outlet ( 133). Here, four movable pieces 17 and case grooves 15 are arranged at equal intervals along the circumference formed by the inner diameter surface 14, and three grooves are equally spaced along the approximate circumference formed by the side surface of the rotor 31. placed at intervals. Here, the width of the arc constituting the air outlet 133 is slightly larger than the width of the arc constituting the air inlet 135, and the arc length is also formed somewhat longer, so that air can be discharged sufficiently and smoothly.

Looking at the operation of the pneumatic motor of the first embodiment of the present invention through FIGS. 6 to 9, first, the rotor in which the V-shaped deep groove part of one groove begins to overlap with the air inlet 135 In the rotational displacement of (31: rotor), the groove is divided into two spaces by the movable piece (17).

For the two spaces separated by the movable piece, the movable piece 17 serves as a kind of check valve. That is, when the compressed air in the front space cannot move to the rear space, while the volume of the rear space is reduced according to the rotation of the rotor and the air is compressed in the rear space, the compressed air moves through the front space due to the pressure difference. It is configured so that it can be moved to

When the rotor rotates and the deep groove part overlaps the air inlet, relatively high pressure compressed air is introduced into the front space of the groove. The front space tends to expand and the rotor rotates. The rear space made up of the tail portion 311a is gradually reduced as the rotor rotates, and accordingly, the compressed air in the rear space ultimately moves to the front space by the check valve function of the movable piece.

When the rotor rotates further and reaches a portion where the groove overlaps the air outlet, the compressed air in the groove is discharged to the outside at a lower pressure through the air outlet. The pressure in the groove is lowered, for example, to the level of the external atmospheric pressure.

Here, the tail portion 311a does not overlap with the air outlet 133 and the air inlet 135, so that the air inlet and the air outlet are directly spatially connected through the tail portion, and the compressed air introduced into the groove from the air inlet is introduced immediately. There is no problem of leakage of compressed air discharged through the air outlet.

Although not shown here, a configuration may be made such that a part of the air discharged through the air outlet is introduced into the case groove. In this case, the inside of the case groove may have a pressure slightly higher than the external atmospheric pressure at which air is discharged and act as a back pressure of the movable piece to act as an air spring. If the elastic force of the air spring is appropriate, it is also possible to couple the movable piece 17 to the case in a simple hinge form without configuring it in the form of a hinge spring as in this embodiment.

10 is a state in which one side of the case is removed from the closing plate 13 in the embodiment of the present invention having the same rotor 31' as in FIG. It is a side view showing

Here, as shown in FIG. 5, bridges 31b are formed on both sides of the rotor 31' in the longitudinal direction of the groove, connecting both entrances in the rotational direction of the deep groove portion, thereby preventing damage caused by vibration, noise, and shock during rotation. It is different from the embodiment of FIGS. 6 to 9 in terms of preventing efficiency degradation, and the groove space is divided as the groove sequentially meets the movable piece, the air inlet and the air outlet according to the rotational displacement of the rotor 31 ', The operation of introducing compressed air into the front space and discharging the compressed air from the groove to the outside, and the operation are made of almost the same concept.

11 to 14 are examples different from those of FIGS. 2 and 5, each having a different number of movable pieces and grooves, viewed from one side in the same direction as the direction of the central axis of rotation of the rotor, with the end plate on one side removed. They are side views.

Among these embodiments, in the embodiment shown in Fig. 11, the movable pieces 17 are arranged at equal angular intervals of 120 degrees on the circumference formed by the inner diameter surface of the case, and the grooves 31a on the side surface of the rotor 31" are located in two places. They are installed at equal angular intervals.

In the embodiment of Fig. 12, the movable pieces are arranged at regular angular intervals of 120 degrees on the circumference formed by the inner diameter surface of the case, and the grooves on the side surface of the rotor are provided at 4 locations at regular intervals.

In the embodiment of Fig. 13, the movable pieces are arranged on the circumference formed by the inner diameter surface of the case at regular intervals of 120 degrees, and the grooves on the side surface of the rotor are provided at five locations at regular intervals of 72 degrees.

In the embodiment shown in Fig. 14, four movable pieces are arranged at equal angular intervals of 90 degrees on the circumference formed by the inner diameter surface of the case, and grooves on the side surface of the rotor are provided at equal angular intervals at five locations.

Under the premise of arranging at equal intervals, if the number of movable pieces and the number of grooves are the same, all grooves receive the same rotational force by compressed air at the same time, but in this case, rotational stability may be reduced because the rotational state is different depending on the rotational section , As a result, the durability of the pneumatic motor may decrease, the rotation efficiency may decrease, and vibration noise may occur.

Therefore, in the above embodiments, the number of movable pieces and the number of grooves are different, so that when one groove receives a large rotational force from compressed air, the other groove does not receive a rotational force or receives a small rotational force. Distributes the rotational force relatively evenly according to the rotational displacement This can make the rotation state of the rotor uniform as a whole. This configuration can be seen as similar to distributing the top dead center of the piston differently in one rotation period in a multi-cylinder internal combustion engine.

In addition, in terms of the first rotational operation of the rotor at startup, the groove and the movable piece are arranged differently, and the installation section, length, and length of the part where the groove is not installed are adjusted If so, the front portion of the at least one groove comes into contact with the air inlet, and starting can be facilitated by simply supplying compressed air without a separate starting device.

Increasing the number of grooves and the number of air inlets and air outlets can increase the output of the pneumatic motor while consuming more compressed air in most cases, but efficiency can increase or decrease depending on the arrangement, so efficient arrangement is desirable. It is also possible to adjust the output of the pneumatic motor by locking or opening a part of the air inlet.

On the other hand, although the air inlet is formed in an arc shape in the above, a plurality of small circular air inlets may be arranged in an arc shape to replace the arc-shaped air inlet, and the output of the pneumatic motor is increased by adjusting the opening and closing of at least some of them. It is also possible to adjust. The same can be applied to the air outlet.

In the above, the present invention has been described based on the illustrated embodiment, but this is only an example, and various modifications may be made therefrom by those skilled in the art, and all or part of the above-described embodiment It will be appreciated that may be configured by selectively combining. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

11: Case 13: Closing plate
14: inner diameter surface (case inner diameter surface) 15: case groove
17: movable piece 18: bearing
31, 31', 31 ": rotor (rotor) 31a: groove
33: rotation center axis 133: air outlet
135: air inlet 311a: tail (tail of groove)

Claims (8)

A cylindrical rotor having a case having a cylindrical inner space and a central axis of rotation cocentric with the central axis of rotation of the case, installed in the case and rotating around the central axis of rotation in the case with a diameter matching the inner diameter of the case. with,
Both ends of the case in the direction of the central axis are closed by a closing plate,
When viewed from one side in the direction of the central axis, at least one air inlet and one or more air outlets of the closing plate are arranged on a circumference smaller than the circumference formed by the inner diameter surface of the case, respectively, and the air inlet and the air outlet A groove is formed on the side surface of the rotor so as to overlap in a direction toward the rotation center,
In a cross section perpendicular to the central axis or one side viewed in the direction of the central axis, at least a portion of the groove is formed to overlap the air inlet and the air outlet in turn as the rotor rotates,
A movable piece capable of changing the degree of protrusion while contacting the side surface of the rotor is installed on the inner diameter surface of the case so that the groove meets the groove first before overlapping with the air inlet based on the rotational direction, so that the rotor rotates while the rotor rotates. The groove is an air-core type pneumatic motor made to meet in order of the movable piece, the air inlet, and the air outlet. According to claim 1,
On the side surface viewed in the direction of the central axis, the groove has a deep groove portion at the front with respect to the rotation direction of the rotor, and a gap between the side surface of the rotor and the inner diameter surface of the case at the rear of the deep groove portion ( Width) is connected to the tail part, which is smaller than the deep groove part,
The tip of the movable piece (the part that protrudes most from the inner diameter surface) of the tail part continuously contacts the side surface of the rotor to divide the front space in front of it and the rear space behind it, and the air in the front space is blown into the rear space. An air core type pneumatic motor made to act as a check valve that prevents it from going into space. According to claim 2,
On the one side viewed in the direction of the central axis, the tail portion always does not overlap with the air outlet and the air inlet and spatially does not communicate with each other. According to claim 2 or 3,
The movable piece is formed in the form of a spring hinge (hinge) in which a spring is installed on the hinge shaft portion, or is configured to form an air spring to receive force directed toward the side surface of the rotor. According to claim 2 or 3,
When the movable piece meets the deep groove portion, in order to prevent the movable piece from excessively moving and generating vibration or noise, when viewed from the one side, both front and rear entrances of the deep groove portion are formed based on the rotational direction of the rotor At least one connecting bridge (guide part) is installed,
The bridge is formed to enable air exchange between the space of the deep groove part and the space of the tail part and air exchange between the groove and the air inlet and the air outlet, respectively. According to claim 2 or 3,
Based on the rotational direction of the rotor, the movable piece, the air inlet, and the air outlet are sequentially located at the same number,
The number of installation combinations of the movable piece, the air inlet, and the air outlet is one or more, the installation distance between the combinations is equal intervals, and the movable piece, the air inlet, and the air outlet in the combination are mutually spaced is an air-core type pneumatic motor made to be the same in all the above combinations. According to claim 2 or 3,
The air-core type pneumatic motor, characterized in that the number of grooves and the number of combinations of the movable piece, the air inlet, and the air outlet are different from each other, and the installation interval of the grooves and the installation interval of the combination are equal intervals, respectively. According to claim 7,
Regardless of the rotational displacement of the rotor
At least one of the grooves is an air-core type pneumatic motor in which the front space is spatially connected to the air inlet.

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