CN1839261B - dual capacity compressor - Google Patents

Abstract

The present invention relates to a dual capacity compressor for preventing relative movement from taking place between components. For this, the present invention provides a dual capacity compressor including a power generating part (20) having a reversible motor (21, or 22) and a crank shaft (23) inserted in the motor (21, or 22), a compression part (30) having a cylinder (32), a piston (31), and a connecting rod (33), a crank pin (110) in an upper part of the crank shaft (23) eccentric from an axis of the crank shaft (23), an eccentric sleeve (120) rotatably fitted between the crank pin (110) and an end of the connecting rod (33), a key member (130, or 230) configured such that the key member is held at at least a part of the eccentric sleeve (120), and held at the eccentric sleeve (120) additionally during operation, for latching the eccentric sleeve (120) with the crank pin (110) positively in both direction rotation of the motor.

Description

dual capacity compressor

technical field

The present invention relates to a compressor for compressing a working fluid such as a refrigerant to a required pressure, in particular to a compressor whose compression capacity varies with the direction of rotation.

Background technique

A dual capacity compressor is a reciprocating compressor whose piston stroke and compression capacity vary with the direction of rotation of the motor and crankshaft by means of an eccentric sleeve rotatably connected to the crankpin of the crankshaft. Because the compression capacity of the dual-capacity compressor can vary with the required load, this dual-capacity compressor is widely used in equipment that needs to compress working fluid, especially in household appliances that work in the refrigeration cycle, such as refrigerators, To improve work efficiency.

US Patent 4236874 discloses a common dual capacity compressor, and the prior art dual capacity compressor will be briefly described below with reference to this patent.

Fig. 1 shows a cross-sectional view of a dual capacity compressor disclosed in US Patent 4,236,874, and Fig. 2 schematically shows the operation of the dual capacity compressor.

Referring to Fig. 1, the dual-capacity compressor is provided with the following key components: a piston 7 located in a cylinder 8; a crankshaft 1; a crankpin 3 whose axis 3a deviates from the axis 1a of the crankshaft 1; The connected eccentric ring 4; and the connecting rod 6 connected between the eccentric ring 4 and the piston 7. The eccentric ring 4 and the connecting rod 6 are rotatable relative to each other and also relative to the axis 3a of the crankpin. The crank pin 3 and the eccentric ring 4 are respectively provided on their contact surfaces with a release area 9 in which a key 5 for connecting the crank pin 3 and the eccentric ring 4 is arranged. The operation of the dual capacity compressor in relation to the compression capacity will be described below. As shown in Figure 2, in a dual-capacity compressor, the stroke of the piston 7 is adjusted by the eccentricity that varies with the position of the eccentric ring 4, wherein, when a larger capacity is required, the crankshaft 1 moves clockwise (forward) , and when less capacity is required, the crankshaft 1 rotates in a counterclockwise (reverse) direction. In detail, Fig. 2A shows the moment when the piston 7 is at the top dead center when it rotates clockwise, and Fig. 2B shows the moment when the piston 7 is at the bottom dead center when it rotates clockwise, at this time, the stroke Lmax is caused by the maximum eccentricity. maximum. Figure 2C shows the moment when the piston 7 is at the bottom dead center when it rotates in the counterclockwise direction, and Figure 2D shows the moment when the piston 7 is at the top dead center when it rotates in the counterclockwise direction.

However, during the above-mentioned running process, the crankpin 3 and the eccentric ring 4 are subjected to centrifugal force due to rotation around the crankshaft axis 1a, and the centrifugal force suffered by the two is respectively perpendicular to the crankshaft axis 1a and the crankpin axis 3a, and is respectively located at a position including the crankshaft axis. 1a and the plane of the crankshaft pin axis 3a and the plane containing the crankshaft axis 1a and the center of gravity 4a of the eccentric ring. Therefore, different from Figures 2A and 2B, in the situation shown in Figures 2C and 2D, since the forces are not on the same straight line, a local rotational moment is generated at the eccentric ring 4 relative to the crank pin 3, the magnitude of which is the centrifugal force of the eccentric ring to The product of the vertical distance "d" of crankpin 3 and its own centrifugal force acting in the same direction as the direction of rotation of crankshaft 1 (counterclockwise). Since the crank pin 3 and the eccentric ring 4 are parts that can move relative to each other, the rotational moment causes the eccentric ring 4 to rotate relatively in the direction of rotation of the crankshaft 1, thereby disengaging the key 5 from engagement with the crank pin 3 and the eccentric ring 4, and The eccentric ring 4 and the key 5 are moved in the rotational direction shown by the dotted line in FIG. 3 . In addition, as shown in FIG. 3 , for example, during rotation in the clockwise direction, the pressure "P" in the compressed cylinder (the pressure of the re-expansion of the working fluid) pushes the eccentric ring 4 in the direction of rotation of the crankshaft 1, so that the eccentric The ring 4 turns relative to the crankpin 3 in the direction of rotation of the crankshaft. As a result, this relative rotation makes the operation of the compressor unstable, and the desired compression performance cannot be obtained.

In fact, the relative rotation occurs because the key 5 cannot hold the crank pin 3 and the eccentric ring well. As long as the rotation direction of the crankshaft changes, the key 5 will roll in the release area, thereby causing severe wear on the contact surfaces and shortening the service life of the compressor.

Meanwhile, besides US Patent No. 4,236,874, there are many patent documents disclosing the technology of dual-capacity compressors, which will be briefly described below.

Similarly, US Patent 4479419 also discloses a dual capacity compressor having crank pins, eccentric cams and keys. The key is fixed to an eccentric cam and follows a track in the crankpin when the direction of rotation of the compressor changes. However, US Patent 4,479,419 also has the problem of unstable operation due to relative rotation, since the key does not hold the crank pin and eccentric cam well.

US Patent 5951261 discloses a compressor having: an eccentric member having a hole passing through the eccentric member and having a certain diameter; and an eccentric cam having another hole on one side thereof, The hole has the same diameter as the hole of the eccentric part. A pin is arranged in the hole of the eccentric part and a compression spring is arranged in the hole of the eccentric sleeve. Thus, when the holes are aligned during rotation, the pin enters the hole of the cam under centrifugal force, thereby connecting the eccentric member and the eccentric cam together. However, since US Patent No. 5951261 provides only one hole in the eccentric cam, the eccentric part and the eccentric cam can only be connected together when the compressor rotates in a specific direction. Furthermore, since the precise movement of the pin from the eccentric through the holes to the cam is difficult, stability in operation cannot be ensured.

Contents of the invention

An object of the present invention is to provide a dual capacity compressor capable of maintaining a fixed eccentricity and operating stably even when the compressor rotates in either direction with different compression capacities.

As described above, the inventors have recognized that during operation, the unstable operation of the dual capacity compressor is caused by the local centrifugal force of the eccentric sleeve and external loads applied through the connecting rod and the like. Although these situations would inevitably arise with the use of an eccentric mechanism, the inventors have realized that this problem could be solved if the crankpin and eccentric sleeve could be rigidly secured during operation. In view of the key member having such a fixed structure, the key member and its related parts are modified to prevent relative rotation between the crank pin and the eccentric sleeve.

In accordance with this, the present invention provides a dual capacity compressor comprising: a power generation unit including a reversible electric motor and a crankshaft inserted into the motor; a compression unit including a cylinder, a piston in the cylinder and a The connecting rod to which the piston is connected; the crankpin, which is on the upper part of the crankshaft and is eccentric with respect to the axis of the crankshaft; and the eccentric sleeve, whose inner peripheral surface rotatably fits the outer peripheral surface of the crankpin , the outer peripheral surface of the eccentric sleeve is rotatably engaged with one end of the connecting rod; the key part, which is configured to be held on at least a part of the eccentric sleeve, is also held on the eccentric sleeve during operation, so that the In each direction of rotation of the electric motor, the eccentric sleeve and the crank pin are rigidly clamped.

The key part is always fixed on a part of the eccentric sleeve, relatively located radially inside the crankshaft. More specifically, the key member includes a first protrusion for always protruding the crank pin by a predetermined length; and a second protrusion for protruding only one end of the crank pin by a predetermined length during operation.

The key prevents the eccentric sleeve from being rotated by the centrifugal force and the resulting rotational moment. In order to achieve this, the key part is always fixed on a part of the eccentric sleeve, so that the direction of the rotational torque generated on the eccentric sleeve is opposite to the direction of rotation of the crankshaft. More specifically, the key part comprises a first protrusion always protruding beyond the crankpin, and a second protrusion always protruding beyond the crankpin, which is fixed to the eccentric sleeve when the compressor is in operation.

In addition, the key member further includes an elastic member that always supports the key member so that at least a part protrudes from the crank pin regardless of the operating state of the compressor. Preferably, the elastic member restricts movement of the key member in one direction. The elastic member has uneven elastic force. The elastic member includes a first elastic member in contact with the key component, and a second elastic member in contact with the first elastic member and the inner peripheral surface of the crank pin respectively, and the elastic force of the second elastic member is greater than that of the first elastic member.

The eccentric sleeve also includes a counterweight for preventing the eccentric sleeve from being disengaged from the key member due to rotation before the key member catches the eccentric sleeve well by changing the center of gravity of the eccentric sleeve. The counterweight places the center of gravity of the eccentric sleeve in a plane containing the longitudinal axis of the crankshaft and the longitudinal axis of the crankpin. The counterweight alters the center of gravity of the eccentric sleeve so as to be positioned opposite a plane containing the longitudinal axis of the crankshaft and the longitudinal axis of the crankpin.

Therefore, the present invention prevents relative rotation between the crank pin and the eccentric sleeve, allowing the compressor to operate stably and improve its efficiency.

Description of drawings

The accompanying drawings, included for a better understanding of the invention, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention.

In the attached picture:

Figure 1 shows a sectional view of a dual capacity compressor of the prior art;

Figure 2 schematically represents the operation of the existing dual capacity compressor in Figure 1;

Figure 3 shows a cross-sectional view of a key part of a conventional double capacity compressor, schematically showing the relative rotation between the crank pin and the eccentric sleeve;

Figure 4 shows a cross-sectional view of a dual-capacity compressor of a preferred embodiment of the present invention;

Figure 5A shows a side view with a partial sectional view of the dual capacity compressor of the first preferred embodiment of the present invention;

Figure 5B shows a top view with a partial cutaway view of the dual capacity compressor of the first preferred embodiment of the present invention;

Figure 6A shows a perspective view of the crankpin of the first preferred embodiment of the present invention;

Figure 6B shows a perspective view of a variation of the crankpin in Figure 6A;

Fig. 7 A shows the perspective view of eccentric sleeve of the present invention;

Figure 7B, 7C and 7D respectively represent the top view, the side view and the perspective view of the modification of the eccentric sleeve of the present invention;

Fig. 8 shows the perspective view of the key member of the first preferred embodiment of the present invention;

Figure 9 shows a plan view of a variant of the key member of Figure 8, which cooperates with the crank pin;

10A and 10B represent perspective views of key components, each key component having a detachable first stopper of the first preferred embodiment of the present invention;

Figures 11A-11C show plan views of key components each having a second stopper of the first preferred embodiment of the present invention;

Fig. 12 represents the plan view of the modified form of the elastic member that is used for the key member of the first embodiment;

13A and 13B are plan views respectively showing the operation of the dual-capacity compressor using the first preferred embodiment, the compressor rotating in a clockwise direction;

14A and 14B are plan views respectively showing the operation of the dual-capacity compressor adopting the first embodiment, the compressor rotating counterclockwise;

Fig. 15A and Fig. 15B are plan views, respectively represent the relation of the force that has the eccentric sleeve of the key part of the first embodiment to rotate clockwise and counterclockwise;

16A to 16C are side views and top views with partial sectional views showing the dual capacity compressor of the present invention employing the key member of the second embodiment;

Fig. 17 is a side view showing a key member of a second preferred embodiment of the present invention;

18 is a plan view showing a modification of a key member installed in a crankpin according to a second preferred embodiment of the present invention;

19A to 19C are plan views respectively showing a key member with a stopper according to a second preferred embodiment of the present invention;

Fig. 20 is a plan view showing a modification of the elastic member used in the key member of the second embodiment;

21A and 21B are plan views respectively showing the operation of the dual-capacity compressor using the key member of the second embodiment, which compressor rotates in a clockwise direction;

22A and 22B are plan views respectively showing the operation of a modified dual-capacity compressor using the key assembly of the second embodiment, which compressor rotates in a counterclockwise direction;

Fig. 23A and Fig. 23B are plan views, respectively represent the relation of the force that has the eccentric sleeve of the key part of the second embodiment to rotate clockwise and counterclockwise;

Figure 24 is a perspective view showing a variation of an eccentric sleeve with a counterweight; and

25A and 25B are plan views showing the relationship of forces generated by clockwise and counterclockwise rotation of an eccentric sleeve with a counterweight, respectively.

Detailed ways

Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. In the embodiments of the present invention, the same components have the same names and reference numerals, and their repeated descriptions are omitted. The overall structure of the dual capacity compressor of the present invention will be described below with reference to FIG. 1 .

As shown in the figure, the dual-capacity compressor of the present invention includes: a power generation part 20, which is located at the lower part of the compressor, for generating and transmitting required power; and a compression part 30, which is located above the power generation part 20, for Power is used to compress the working fluid. In addition to these basic components, the dual capacity compressor also includes a stroke switching component 100 connected between the power generation component 20 and the compression component 30 for changing the compression capacity of the compression component 30 during operation. . At the same time, there is also a casing that encapsulates the power generating part 20 and the compressing part 30 to prevent leakage of the refrigerant, and a frame 12 that is elastically supported on a plurality of supports (ie, springs) connected to the inside of the casing . The compressor also has a refrigerant inlet 13 and a refrigerant outlet 15 mounted to and communicating with the inside of the casing.

The power generating part 20 located under the frame 12 includes: a motor having a stator 21 and a rotor 22 that generates rotational force using an external power source; and a crankshaft 23 . The motor is reversible. The lower part of the crankshaft 23 is inserted into the rotor 22 for power transmission, and the crankshaft 23 has an oil hole or an oil groove for supplying lubricating oil stored in the lower part to each driving part.

The compressing part 30 is installed on the frame 12 above the power generating part 20 and includes: a mechanical drive part for compressing refrigerant; and a suction valve and a discharge valve for assisting the drive part. In addition to the cylinder 32 that actually forms the compression space, the driving member has a piston 31 for reciprocating movement inside the cylinder 32 and a connecting rod 33 for transmitting the reciprocating power of the piston 31 . Valves are combined with the cylinder head 34 and the cylinder front cover 35 to receive/discharge refrigerant into/from the cylinder 32 .

The stroke switching part 40 of the dual capacity compressor of the present invention will be described in detail below, while omitting the description of the same power generating part and compressing part as the prior art.

Referring to FIG. 5A, the stroke conversion part 40 generally includes: a crank pin 110, which is located at the top of the crankshaft and is eccentric relative to the crankshaft; an eccentric sleeve 120, which is rotatably fitted on the outer peripheral surface of the crank pin 110 and the connecting rod 33; and the key member 130 fitted in the crankpin 110. The key member 130 maintains the relative position between the crank pin 110 and the eccentric sleeve 120 during operation of the compressor. In this stroke conversion part 100, the eccentric sleeve 120 is rotatably arranged between the connecting rod 33 and the crank pin 110, so that its effective eccentricity varies with the rotation direction of the motor (forward or reverse). Change. In order to maintain the changed effective eccentricity, the key part 130 clamps the eccentric sleeve 120 . Therefore, in the stroke conversion component 100, when the rotation direction of the motor changes, the stroke length of the connecting rod and the displacement of the piston change with the effective eccentricity, thereby making the compression capacity also change with the rotation direction. The stroke conversion component 100 of the present invention has been briefly introduced above, and will be described in detail below with reference to the accompanying drawings.

Figures 5A and 5B show, respectively, a side view and a cross-sectional view of a dual capacity compressor of the present invention, with components of the assembled compressor partially cut away for convenience and clarity. 6A to 12 show each component individually.

Referring to FIG. 5A , the crank pin 110 is partially hollow, and the key member 130 is movably installed in the hollow portion. The crank pin 110 also has a pair of key member engaging portions 111 opposed to each other, and has an oil passage 112 and an oil supply hole 113 at a lower portion.

Referring to FIGS. 5A and 5B, the fitting portions 111a and 111b are formed in the hollow tubular portion such that they lie in a vertical plane containing the crankshaft axis 23a and the crankpin axis 110a. Therefore, the key member 130 in the fitting portions 111a and 111b is affected by the centrifugal force 'F' along the length direction of the key member 130 and in the plane where the shaft 23a and the shaft 110a are located. The key part 130 is movable by being guided by the matching parts 111a and 111b under the centrifugal force 'F'. As shown in FIG. 6A, the fitting portions 111a and 111b actually form through holes. The matching portion 111 of the through hole can prevent the key component 130 from falling off when the compressor is running. Preferably, as shown in FIG. 6B , at least one of the fitting portions 111 a and 111 b may be a groove extending from the top end of the wall of the crankpin 110 to a position where the key member 130 is easily installed on the crankpin 110 . More preferably, a seat portion 111c is provided at the end of the fitting portion to stably fit the key member 130 .

Referring to FIG. 5A , the oil passage 112 communicates with the oil groove in the outer surface of the crankshaft 23 and the oil supply hole 113 . The oil supply hole 113 is perpendicular to the extension line of the connecting portion 111a and 111b. When the compressor is running, the lubricating oil at the bottom of the compressor first passes through the oil groove and the oil passage 112, and then is sprayed out to be supplied between the contact surfaces of the components during operation, so as to prevent the wear of the components and make the components run smoothly; the lubricating oil It is also possible to directly feed into the gap between the crank pin 110 and the eccentric sleeve 120 via the oil supply hole 113 . Preferably, the position of the crank pin 110 is higher than that of the eccentric sleeve 120 so that lubricating oil can be evenly sprayed onto the components from a height.

The eccentric sleeve 120 mainly has an inner peripheral surface rotatably coupled with an outer peripheral surface of the crank pin 110 , and an outer peripheral surface rotatably coupled with one end of the connecting rod 33 . In more detail, as shown in FIG. 7A , the eccentric sleeve 120 includes: a track portion 121 formed along the circumference of the eccentric sleeve 120 , and a limiting portion 122 for limiting the track of the track portion 121 . There are two steps 123a and 123b between the rail portion 121 and the restricting portion 122 . As shown in FIG. 5A , the track portion 121 enables the eccentric sleeve itself to rotate relative to the key member as at least a portion of the key member 130 protrudes and engages with the eccentric sleeve 120 when the compressor is not operating. That is, the eccentric sleeve 120 is rotatable around the crank pin 110 within a range defined by the track portion 121 formed therein. The restricting portion 122 opposite to the rail portion 121 restricts the rotation of the sleeve and key member 130 when stopped or moved. Actually, the key member 130 is stuck at the steps 123a and 123b.

Actually, in the eccentric sleeve 120 , the track portion 121 may be a cut-off portion extending in the circumferential direction from the top end of the eccentric sleeve 120 to a desired depth. As shown in Figures 5B and 7B, the steps 123a and 123b are parallel to a plane containing the crankshaft axis 23a and the crankpin axis 110a. That is, the steps 123a and 123b are parallel to the line between the maximum thickness and the minimum thickness of the eccentric sleeve so as to have different widths, and when the compressor is running, the line is located on a plane containing the axes 23a and 110a . Or it can be said that when the compressor is running, the plane where the steps 123a and 123b are located is parallel to the plane containing the axes 23a and 110a. Therefore, the key part 130 located on the same plane can be caught by the steps 123a and 123b at the same time, so that the steps 123a and 123b actually form a surface that contacts the key part 130 in common. Preferably, the steps 123a and 123b are separated from the plane containing the axes 23a and 100a by half the thickness "t" of the key member 130 . According to this, the key part 130 can be more stably and precisely held at the steps 123a and 123b. On the other hand, the steps 123a and 123b may have inclined surfaces inclined at a certain angle with respect to the plane of the axes 23a and 110a, respectively. More specifically, the steps 123c and 123d may be formed along the radial extension of the crankpin axis 110a and perpendicular to the crankpin axis 110a while being inclined at an angle θ to the plane where the axes 23a and 110a lie. Also, the steps 123e and 123f may be inclined at an angle to the restricting portion around the intersection point with the inner peripheral surface. Even in the above case, the steps 123c, 123d, 123e, and 123f have at least a common contact point with the key member 130 so as to be able to engage with each other. In addition, the track portion 121 can be not only a cut-off portion as shown in FIG. 7A , but also a through hole extending along the circumferential direction at a certain distance from the top of the sleeve 120 as shown in FIG. 7D . The rail portion 121 formed by such a through hole can keep the key member 130 from coming off in the vertical direction.

In addition, referring to FIG. 7C , the eccentric sleeve 120 may also include an oil supply hole 124 oppositely formed at a certain height. The oil supply hole 124 may be a symmetrical through hole with respect to the plane where the axes 23a and 110a are located, so that when the key member 130 is held on the eccentric sleeve 110, the oil supply hole 124 is connected with the oil supply hole 113 in the crankpin Pass. Therefore, during operation of the compressor, one of the two oil supply holes 124 always communicates with the oil supply hole 113 regardless of the rotation direction, so that lubricating oil can be supplied to the eccentric sleeve 120 and the connecting rod 33 . In addition, an oil groove 124 a is formed at a certain depth around the oil supply hole 124 for forming a space for distributing lubricating oil around the oil supply hole 124 so that lubricating oil can be easily supplied between the eccentric bush 120 and the connecting rod 33 . Referring again to FIG. 7A, the eccentric sleeve 120 may also include a seat 125 at each of the steps 123a and 123b. The seat 125 accommodates the key member 130 when the key member 130 is held by the eccentric sleeve 110 . The seat 125 may actually be a groove in the step 123a or 123b, and preferably a portion of the key member 130 fits into a portion of the step 123 . Thanks to the seat 125 , the key part 130 can thus be held stably within the eccentric sleeve 120 . In addition, due to the seat 125, the key member 130 and the eccentric sleeve 120 are not in point contact but in surface contact. Therefore, even if there is repeated contact between the key member 130 and the eccentric sleeve 120 when the compressor is operating, neither the key member 130 nor the eccentric sleeve 120 will be broken due to stress concentration and fatigue. Furthermore, as shown in FIGS. 5A and 7C , a ring 126 may be provided between the eccentric sleeve 120 and the crankshaft 23 . Since the annular member 126 and the eccentric sleeve 120 are in line contact, the friction between them can be effectively reduced, and the rotation is smoother than that of the eccentric sleeve 120 alone.

5A, 5B and 8 respectively show the key member of the first preferred embodiment of the present invention. As shown in the figure, the key member 130 of the first preferred embodiment of the present invention basically includes: a first protrusion 131 protruding from the crank pin 110 by a certain length even when the compressor is not in operation; Protrudes a certain length from the crank pin 110 when the compressor is running. The key component 130 also includes a first stopper 133 for limiting the protruding length of the first protruding portion 131 . In addition, the key component 130 also includes an elastic member 140 for adjusting the position of the key component 130 when the compressor is stopped or running. In the present invention, the key member 130 clamps the eccentric sleeve 120 when moved by centrifugal force. As mentioned above, in particular the second protrusion 132 protrudes to hold the eccentric sleeve 120 during operation. In order to protrude due to centrifugal force during operation, the second protruding portion 132 needs to be in the same direction as the centrifugal force. Thus, as shown, the first protrusion 131 is relatively positioned on the inside of the radius of the crankshaft 23 and crankpin 110 while the second protrusion 132 is positioned relatively outside of the radius of the crankshaft 23 and crankpin 110 . In other words, in practice, the second protrusion 132 is arranged inside the crankpin 110, away from the crankshaft axis 22a, for bearing a large centrifugal force, whereas the first protrusion 131 is arranged close to the center 22a in contrast. . In addition, in order to simultaneously lock the eccentric sleeve 120 during operation, it is preferable that the length of the key member 130 is greater than the outer diameter of the crank pin 110 .

In more detail, as shown in FIG. 5A, the first protrusion 131 protrudes from the crank pin 110 and always engages with one of the steps 123a and 123b regardless of the operating state of the compressor (stopped or running), so that even in Also remains engaged while the compressor is running. To this end, an elastic member 140 is installed on the second protrusion 132 , which elastically supports the first stopper 133 together with the inner wall of the crankpin 110 . The protruding length of the first protrusion is defined due to the first stopper 133 of the key member 130 being blocked by the inner wall of the crank pin 110 . In order to make the operation more stable, it is preferable that the length of the first protrusion is at least half of the minimum width of the steps 123a and 123b. In addition, as described above, the first protruding portion 131 is located radially inward of the crankshaft 23 and the crank pin 110 , and the first protruding portion 131 always protrudes radially inward (that is, the axis 23 a of the crankshaft). Therefore, the key member 130 is always held by at least a portion of the eccentric sleeve 120 which is located relatively radially inward of the crankshaft 23 .

The second protrusion protrudes in an opposite direction to the first protrusion so as to engage with the other step when the compressor is operating. In this way, the first protruding portion 131 and the second protruding portion 132 of the key member 130 are engaged with the eccentric sleeve 120 at the same time. The centrifugal force along the key member 130 gradually increases as the rotation speed of the crankshaft 23 increases to overcome the elastic force of the elastic member 140 . Therefore, the second protrusion moves and protrudes in the direction of the centrifugal force (ie, the length direction of the key member along the plane where the axes 23a and 110a lie). In this case, when the compressor changes the rotation direction, the eccentric sleeve 120 rotates around the crank pin 110 to change the eccentricity. Therefore, in order not to hinder the rotation of the eccentric sleeve 120, the length of the second protrusion 132 is such that the tip does not protrude beyond the outer peripheral surface of the crank pin 110 when the compressor is not in operation.

The first and second protrusions 131, 132 are alternately engaged with the steps 123a and 123b according to the rotation direction of the crankshaft. Since the key part 130 is perpendicular to the axes 23a and 110a and is located at or at least parallel to the plane in which the axes 23a and 110a lie, if the thicknesses "t1" and "t2" of the first and second protrusions are different, the key part 130 and the step The contact positions of 123a and 123b are also different. Therefore, the thicknesses "t1" and "t2" of the first and second protrusions should be the same in order to precisely engage with the steps 123a and 123b. Although the cross-section of the key part 130 in the specification and drawings of the present invention is circular, any cross-sectional shape capable of engaging the steps 123a and 123b, such as a square or a hexagon, may be employed.

As shown in FIG. 9 , the contact surface 133 a of the first stopper 133 may have a shape that fits the inner peripheral surface of the crankpin 100 . Accordingly, the key member 130 can be closely engaged with the crank pin 110 and run more smoothly due to increased weight (ie, increased centrifugal force makes it easier for the second protrusion 132 to protrude). Preferably, the first stopper 133 may further include a recess 133b for stably receiving the elastic member 140 . Such contact surfaces 133 a and recesses 133 b can actually assist in increasing the operational stability of the key member 230 . Meanwhile, the first stopper 133 can be manufactured integrally with the key part 130 , or can be an independent part installed on the key part 130 . 10A and 10B show an example of the first stopper 133 of the independent type.

Referring to FIG. 10A , the first stopper 133 may include a protrusion 133a extending radially inward. Accordingly, the first stopper 133 is fitted on the key member 130 when the protrusion 133a is fitted into the circumferential groove of the key member 130 in place. Alternatively, as shown in FIG. 10B , the first stopper 133 of a simple ring can be fixed in place on the key member 130 by fasteners. This independent type of stopper 133 enables the key member 130 to be mounted on the crank pin 130 even when both key member fitting portions 111a and 111b are through holes. More specifically, by placing the stopper 133 inside the crank pin 110 and by inserting the key member 130 into the through hole, the stopper 133 can be connected with the key member 130 .

Meanwhile, as mentioned above, during normal operation, the protruding length of the second protruding portion 132 in the key part 130 can be adjusted by the elastic force of the elastic member 240 . However, the momentary rapid acceleration of the crankshaft 23 and crankpin 110 upon compressor start-up subjects the key member 130 to considerable momentary centrifugal forces. The centrifugal force causes the second protruding portion 132 to protrude excessively under the action of a sufficiently large centrifugal force, thereby causing the first protruding portion 131 to disengage from the matching portion 111 . Therefore, preferably, the key component 130 further includes a second stopper 134 for limiting the protruding length of the second protruding portion 132 from the crank pin 110 when subjected to centrifugal force.

Referring to FIG. 11A , the second stopper 134 may be a hollow tubular member 134 a installed on the second protrusion 132 in a manner to be movable along the length direction of the second protrusion 132 . In this case, the elastic member 140 is installed between the second stopper 134 a and the second protrusion 132 . When the key member 130 moves in the centrifugal force direction, the second stopper 134a contacts the first stopper 133 and the inner wall of the crank pin 110, thereby preventing the first protrusion 133 from protruding beyond a certain length. As shown in FIG. 11B , the second stopper 134 may be an extension portion 134 b whose thickness is at least greater than that of the second protruding portion 133 . That is to say, the second stopper 134b in FIG. 11B is actually a longitudinal extension of the first stopper 133 . At this time, the elastic member 140 is installed on the outer peripheral surface of the second stopper 134b. Alternatively, as shown in FIG. 11C , the second stopper 134 may be a radially extending portion 134 c of the second protrusion radially extending to a desired thickness, and its shape is actually similar to that of the first stopper 133 . At this time, the elastic member 140 is installed between the second stopper 134 b and the inner peripheral surface of the crankpin 110 . Similar to the modification of the first stopper 133 described in FIGS. 10A and 10B , the stoppers 134 b and 134 c may be fixed to the key member 130 as separate parts, respectively.

Alternatively, as shown in FIG. 12 , an elastic member 140 may be used instead of the second stopper 134 to limit the movement of the key member 130 , more specifically, to limit the movement of the second protrusion 132 . For this reason, the elastic member 140 has a non-uniform elastic coefficient, so that one part of the spring has a larger elastic force than the other part. In this way, the deformation of the elastic member 140 is relatively small when the compressor is running, so as to reduce the protruding length of the second protruding portion 132, so that the protruding of the second protruding portion 132 is greatly affected even when an instantaneous excessive centrifugal force acts on it. A large degree of restraint thereby prevents the first protrusion 131 from coming off the crankpin 110 . More preferably, if the elastic force of a part of the elastic member 140 is greater than the maximum centrifugal force of the compressor, excessive protrusion of the second protruding portion 132 can be prevented very well.

Referring to FIG. 12 , such an elastic member 140 actually includes a first elastic member 141 having a predetermined elastic force, and a second elastic member 142 having a greater elastic force than the first elastic member 141 . The first elastic member 141 is in contact with the first stopper 133 for keeping the first protruding portion 131 protruding. Similarly, the second elastic member 142 is in contact with the first elastic member and supported on the inner peripheral surface of the crank pin 110 for protruding the first protruding portion 131 and deforming together with the first elastic member 141 . More specifically, as shown, if the elastic member 140 is in the form of a spring, the first elastic member 141 is a spring with a predetermined diameter, and the second elastic member 142 is always connected to the first elastic member 141 and has a larger diameter. A spring, which is designed to have a greater spring rate and therefore a greater spring force. As mentioned above, preferably, the elastic force of the second elastic member 142 is greater than the maximum centrifugal force of the compressor, so as to well prevent the second protruding portion 142 from protruding excessively. That is to say, in this case, only the first elastic member 141 is deformed, while the second elastic member 142 will not be deformed by the centrifugal force. Therefore, similar to the second stopper 134 , the second elastic member 142 prevents the key part 140 from moving excessively. Since the elastic member 142 can prevent the key part 130 from coming off even without the second stopper 134, the structure of the key part 130 can be simplified and also the key part 130 can be easily installed.

In summary, the length of the key member 130 is substantially longer than the diameter of the crankpin by at least a predetermined amount, and is movably mounted within the crankpin. Even if the compressor is not running, at least a part of the key member 130 (i.e., the first protrusion) protrudes from the crank pin, and another part of the key member 130 (i.e., the second protrusion) is released from the crankshaft by centrifugal force when the compressor is operating. Pin 110 protrudes. That is, the key part 130 is always held on at least a part of the eccentric sleeve 120, and also the key part 130 is held on the eccentric sleeve 120 even when the compressor is operating. Therefore, the key part 130 is mainly in contact with the eccentric sleeve 120 at multiple points, and more specifically, when the compressor is running, the key part 130 and the eccentric sleeve 120 are arranged on opposite sides of any center line in the horizontal plane. contacts at the same time. Ultimately, the key member 130 rigidly engages the eccentric sleeve 120 with the rotating crankpin 110 in either direction of rotation of the motor, thereby preventing the eccentric sleeve 120 and crankpin 110 from moving relative to each other.

The operation of the dual-capacity compressor of the present invention will be described below with reference to the accompanying drawings. Fig. 13A and Fig. 13B respectively show the plan view of the double capacity compressor of the present invention when it runs clockwise, and Fig. 14A and 14B respectively show the plan view of the double capacity compressor of the present invention when it runs counterclockwise.

FIG. 13A shows the relative position between the key member 130 and the eccentric sleeve 120 when the crankshaft starts to rotate in the forward direction (ie clockwise). As mentioned above, the first protruding portion 131 always protrudes from the crankpin 110 due to the inward elastic force along the radial direction of the crankpin 110 . In the state where the first protrusion 131 is protruded, if the crankshaft 23 starts to rotate clockwise, the crank pin, the eccentric sleeve, and the key members 110, 120, 130 also start to rotate clockwise about the axis 23a of the crankshaft. During the rotation, there is a relative frictional force 'f' between the crankpin 110 and the connecting rod 33 which is opposite to the direction of rotation. Therefore, the eccentric sleeve 120 is rotated counterclockwise around the crank pin 110 by the frictional force 'f' until the step 123b on the thin-walled side catches the first protrusion 131 . Once the crankshaft 23 rotates, since the frictional force is always generated when the crankshaft 23 rotates, the stuck state between the first protrusion 131 and the step 12b is always maintained. At this time, as shown in Figure 13B, if the rotational angular velocity reaches a certain value, the key component 130 will follow the direction of action of the centrifugal force 'F', that is, the length direction of the key component in the plane where the axes 23a and 110a are located, in the direction of the centrifugal force 'F' Move under the action of F'. Therefore, the second protrusion 132 engages with the step 223a on the thick side, and at the same time, the first protrusion maintains a state of being in contact with the step 123b. This multi-point simultaneous contact enables the key member 130 to fully engage with the eccentric sleeve 120 . Therefore, when rotating in the forward direction, even if the external force 'P' generated by the expansion of the compressed working fluid and other forces are transmitted through the connecting rod 330, there will be no relative rotation between the crank pin 210 and the eccentric sleeve 220. Furthermore, even if a partial rotational moment is generated at the eccentric sleeve 120 , the eccentric sleeve 120 is prevented from rotating relative to the crank pin 110 . In addition, referring to Fig. 13B, the solid line part in the figure represents the top dead center state, the dotted line part in the figure represents the bottom dead point state, and the eccentric sleeve 220 is set as the piston connected to the connecting rod 33 when forward rotation (not shown) and crankpin 110 provide maximum eccentricity. Therefore, the piston reciprocates within the maximum stroke length Lmax, so that the compressor of the present invention has the maximum compression capacity.

At the same time, if the crankshaft 23 starts to reverse, that is, rotates in the counterclockwise direction, a relative frictional force 'f' that is opposite to the direction of rotation, that is, in the clockwise direction, is generated between the crankpin 110 and the connecting rod 33. Subsequently, the eccentric sleeve 120 starts to rotate clockwise around the crank pin 110a from the position shown in FIG. 13A until the step 123a on the thick wall side engages with the first protrusion 131 , as shown in FIG. 14A . Similarly, as the crankshaft 23 rotates, the engagement between the first protrusion 131 and the step 123a is maintained by frictional force 'f'. Similar to forward rotation, as shown in FIG. 14B, if the rotational angular velocity reaches a certain value, the second protrusion 232 engages with the step 123b on the thin-walled side under the action of centrifugal force 'F', thereby making the eccentric sleeve 120 and The key components 130 are in a multi-point contact state. Therefore, in reverse rotation, relative rotation between the crank pin 110 and the eccentric sleeve 120 can be prevented even if there is an external force 'P' of the working fluid acting on the piston at the time of compression and any other force received. In addition, as shown in FIG. 14B, during reverse rotation, since the eccentric sleeve 120 is set to have the minimum eccentricity, the piston reciprocates within the minimum stroke length Lmin, thereby enabling the compressor of the present invention to have the minimum compression capacity .

In a word, the relative movement between the parts maintaining the eccentricity, that is, the crank pin 110 and the eccentric sleeve 120 is well eliminated by the key part 130, and the compressor of the present invention can be in any state, that is, forward rotation or reverse rotation stable operation.

Meanwhile, referring to FIGS. 15A and 15B , the eccentric sleeve 120 has an eccentric center of gravity 'G' due to its structure. That is, the center of gravity 'G' is on the heavier side of the restricting portion 122 . When the crankshaft 23 rotates, the centrifugal force 'C' acts on the center of gravity 'G' along the extension of the line between the center of gravity 'G' and the crankshaft axis 23a and in a direction perpendicular to the axis 23a of the crankshaft 23. Since the center of gravity 'G' is eccentric, the centrifugal force 'C' produces a rotational moment 'M' about the crankpin axis 23a. In more detail, as shown, the rotational moment 'M' can be expressed as the product of the centrifugal force 'C' and the moment arm length d perpendicular to the crankpin axis 23a. This rotational moment 'M' acts in the same direction as the rotation of the crankshaft. That is to say, as shown in Figure 15A, when rotating clockwise, the eccentric sleeve generates a clockwise rotational moment due to the center of gravity 'G'; as shown in Figure 15B, when rotating counterclockwise, the eccentric sleeve generates a torque 'G' to produce a counterclockwise rotational moment. As mentioned above, when the frictional force 'f' tends to rotate the eccentric sleeve 120 in the direction opposite to the direction of rotation until the eccentric sleeve 120 engages with the first protrusion 131, the rotational moment 'M' tends to move toward The direction of rotation of the compressor turns the eccentric sleeve 120 . Accordingly, the rotational moment 'M' may cause intermittent micro-rotation of the eccentric sleeve 120 , thereby causing disengagement of the eccentric sleeve 120 from the key member 130 . The rotation of the eccentric sleeve 120 hinders the protrusion and catch of the second protrusion.

The key part 230 of the second embodiment can prevent the rotation of the eccentric sleeve 120 caused by centrifugal force 'C'/rotational moment 'M'. 16A-16C and 17 illustrate the key member 230 in detail.

As shown in the figure, the key component 230 of the second embodiment basically includes: a first protruding portion 231 and a second protruding portion 232 , and each protruding portion always protrudes beyond the crankpin 110 by a certain length during operation. The second protrusion 232 does not engage with the eccentric sleeve 120 when the compressor is stopped, but moves and engages with the eccentric sleeve 120 when the compressor is running. The key component 230 also includes a first stopper 233 for limiting its movement in a certain direction. The first stopper 233 limits the radially inward movement of the second protruding portion 232 and defines the protruding length of the second protruding portion 232 . In addition, similar to the first embodiment, an elastic member 140 is provided on the key component 230 for adjusting the position of the key component 230 . As previously shown in FIGS. 15A and 15B, since the eccentric sleeve 120 is rotated by the centrifugal force 'C' and the rotational moment 'M', it is difficult for the key member 130 to catch a radially outer portion of the eccentric sleeve 120. Therefore, it is preferable that the key member 230 of the second embodiment has a portion that engages with the radially outer portion of the eccentric sleeve 120 when the compressor is started to operate. For this reason, when the first protruding portion 231 to be maintained in a protruding state is located radially outside of the crankshaft 23 and the crankpin 110 , the second protruding portion 231 is located radially inward. In other words, to prevent rotation of the eccentric sleeve 120, the first protrusion 231 is disposed within the crank pin 110 away from the axis 22a of the crankshaft, and oppositely, the second protrusion 131 is disposed close to the axis 22a.

In more detail, as shown in FIG. 16A , the first protruding portion 231 has a sufficient length to maintain its protruding crankpin 110 , and as described above, the first protruding portion 231 faces the crankshaft 23 in the direction of the centrifugal force generated during operation. And the radially outer side of the crankpin 110 protrudes. Therefore, as shown in FIG. 16C , the first protrusion 231 further protrudes radially outward due to the centrifugal force during operation, and thus remains engaged with the eccentric sleeve 120 even during operation of the compressor.

The second protruding portion 232 protrudes from the crankpin 210 in a direction opposite to the first protruding portion 231 under the elastic force of the elastic member 140 . For this, an elastic member 140 is installed on the first protrusion 231 to elastically support the first stopper 233 together with the inner wall of the crankpin 110 . The first stopper 233 on the key member 130 is caught on the inner wall of the crank pin 110 , thereby limiting the protruding length of the second protrusion 232 . Meanwhile, when the compressor changes the rotation direction, the elastic sleeve 120 rotates around the crank pin 110 to change the eccentricity. Therefore, in order not to hinder the rotation of the inner rod 120 of the eccentric sleeve, the second protruding portion 232 should not protrude from the crank pin 110 when the operation is stopped, so as to prevent the second protruding portion 232 from interfering with the eccentric sleeve 120 . In more detail, as shown in the figure, the second protrusion 232 has a groove 232a through which the eccentric sleeve 130 can pass. Preferably, the width of the groove 232a is slightly larger than the maximum width of the eccentric sleeve 130 . This groove 232 a allows the end 32 b of the second protrusion to lie outside the eccentric sleeve 120 . During operation, the centrifugal force 'F' generated along the key part 230 becomes larger as the rotation speed of the crankshaft 23 increases, and becomes greater than the elastic force of the elastic member 140 . The second protrusion moves in the direction of the centrifugal force (the length direction of the key member along the plane where the axes 23a and 110a lie) under the action of the centrifugal force 'F' until the end of the second protrusion 232b is blocked by the eccentric sleeve 120, As shown in Figure 16C. Therefore, the first and second protrusions 231, 232 of the key member 230 are simultaneously engaged with the eccentric sleeve 120 when the compressor is operating.

The key member 230 of the second embodiment can be used in the dual capacity compressor of the present invention without modifying the crank pin 110 and the eccentric sleeve 120 . Since the crank pin 110 and the eccentric sleeve 120 have been described with reference to FIGS. 6A to 7D , further descriptions of the crank pin 110 and the eccentric sleeve 120 will not be given even if the key member 230 has other features.

Referring to FIG. 18 , the first stopper 233 includes a contact surface 233 a shaped to match the inner peripheral surface of the crankpin 110 , and preferably has a recess 233 b adapted to accommodate the elastic member 140 . The contact surface 233a and the dimple 233b contribute to the stable operation of the key member 230 of the second embodiment. The first stopper 233 can be integrally formed with the key part 230, or can be manufactured as an independent part.

During normal operation, the protrusion and movement of the first and second protrusions 231 , 232 can be adjusted by the elastic force of the elastic member 140 . However, as mentioned above, the key part 230 is easily disengaged under the instantaneous centrifugal force, especially the second protrusion 232 cannot be precisely engaged with the eccentric sleeve 120 . In order to prevent the key component 230 from operating abnormally, preferably, a second stopper 234 can be further used to limit the movement of the key component 230 in the direction of the centrifugal force. As shown in FIGS. 19A to 19C , the shape of the second stopper is the same as that of the first embodiment. That is to say, the stopper 234 of this second embodiment may be a hollow member 234a (see FIG. 19A ) installed on the second stopper 234 in a manner movable along the length direction, or a first stopper The extending portion 234b in the length direction of 133 (see FIG. 19B ), or the extending portion from which the first protruding portion 231 protrudes radially outward by a predetermined thickness (see FIG. 19C ).

In addition, referring to FIG. 20 , similar to the first embodiment, the key component 230 of the second embodiment may use an elastic member 140 with uneven elastic force instead of the second stopper 234 . As shown in the figure, the elastic member 140 has a first elastic member 141 with a predetermined elastic force and a second elastic member 142 with a stronger elastic force than the first elastic member 141 . In fact, the first elastic member 141 is a spring with a predetermined diameter, and the spring diameter of the second elastic member 142 is larger than that of the first elastic member, so it has a larger elastic coefficient and elastic force. The elastic force of the second elastic member 141 is greater than the maximum centrifugal force of the compressor, so as to fundamentally prevent the key component 230 from moving excessively. The elastic member 140 restricts the movement of the key part 230 in the direction of the centrifugal force, so as to prevent the key part 230 from disengaging from the eccentric sleeve or locking the eccentric sleeve without success. In addition, the key part 130 is simplified and the key part 130 is easy to install because an additional part such as the second stopper 234 can be provided.

The operation of the dual capacity compressor having the key member of the second embodiment of the present invention will be described below with reference to the drawings. Fig. 21A and Fig. 21B respectively show the plan view of the dual capacity compressor of the present invention rotating clockwise, and Fig. 22A and Fig. 22B respectively represent the plan view of the dual capacity compressor of the present invention running counterclockwise.

FIG. 21A shows the relative positional relationship between the key member 130 and the eccentric sleeve 120 when the crankshaft starts to rotate clockwise. As mentioned above, the first protruding portion 231 always protrudes beyond the crankpin 110 under the action of the elastic force radially inward of the crankpin 110 . In the state where the first protrusion 231 protrudes, if the crankshaft 23 starts to rotate clockwise, the crank pin, the eccentric sleeve, and the key members 110, 120, and 130 also start to rotate clockwise about the axis 23a of the crankshaft. During the rotation, a relative frictional force 'f' is generated between the crankpin 110 and the connecting rod 33 which is opposite to the direction of rotation, that is, in the counterclockwise direction. Therefore, the eccentric sleeve 120 rotates counterclockwise around the crank pin 110 under the action of the frictional force 'f' until the eccentric sleeve 120, more specifically, the restricting portion 122 passes through the groove 232a of the second protrusion, and The step 123 b on the thin-walled side is caught on the first protruding portion 231 . As shown in FIG. 23A, since the first protruding portion 231 clamps the eccentric sleeve 120 at a position relative to the radially outer side of the crankshaft, relative to the action line of the centrifugal force (perpendicular to the axes 23a and 110a, and located at the axes 23a and 110a In terms of plane), the center of gravity 'G' of the eccentric sleeve 120 is opposite to the position of the center of gravity in FIG. 15A . Due to the position of the center of gravity 'G', the centrifugal force 'C' produces a rotational moment 'M' which is opposite to the direction of rotation (counterclockwise). Therefore, the rotation moment 'M', together with the friction force 'f' acting in the same direction, rotates the eccentric sleeve 120 in the direction opposite to the rotation direction, that is, counterclockwise, so that the gap between the first protrusion 231 and the step 123b Stable engagement. Subsequently, as shown in FIG. 21B, if the rotational angular velocity reaches a certain value, the key component 130 will be along the direction of the centrifugal force 'F', that is, the length direction of the key component in the plane where the axes 23a and 110a are located, under the centrifugal force 'F' move under the influence of Therefore, as described above with reference to FIG. 16C , the end portion 232b of the second protrusion 132 engages with the step 223a on the thick side while the first protrusion 131 remains in contact with the step 123b. As described above, since the first protrusion 231 is stably engaged by the rotational moment 'M' opposite to the rotation direction, the second protrusion 232 can smoothly catch the eccentric sleeve 120 . This multi-point simultaneous contact enables the key member 130 to fully engage with the eccentric sleeve 120 . Therefore, in forward rotation, even if the compressed working fluid is re-expanded due to external force 'P' and other forces are transmitted through the connecting rod 330, the relative rotation between the crank pin 210 and the eccentric sleeve 220 can be prevented. . Furthermore, even if a partial rotational moment is generated at the eccentric sleeve 120 , the eccentric sleeve 120 is prevented from rotating relative to the crank pin 110 . Also, referring to FIG. 21B , the solid line part in the figure represents the top dead center state, the dotted line part in the figure represents the bottom dead point state, and the eccentric sleeve 220 is set to provide the maximum eccentricity during forward rotation. Therefore, the piston reciprocates within the maximum stroke length Lmin, whereby the compressor of the present invention has a minimum compression capacity.

If the crankshaft 23 starts to reverse direction, that is, rotates in the counterclockwise direction, a relative frictional force 'f' that is opposite to the direction of rotation, that is, in the clockwise direction, is generated between the crankpin 110 and the connecting rod 33. Therefore, the eccentric sleeve 120 starts to pass through the groove 232a from the position shown in FIG. until the first protruding portion 131 is engaged, as shown in FIG. 22A . As shown in Fig. 23B, the principle of clockwise rotation is the same, and the center of gravity 'G' of the eccentric sleeve relative to the line of action of the centrifugal force is opposite to the position of the center of gravity in Fig. 15B. Therefore, the centrifugal force 'C' produces a clockwise rotational moment 'M' opposite to the rotational direction, which acts in the same direction as the frictional force, and together they maintain the gap between the first protrusion 231 and the step 123a. Stable engagement. As shown in Figure 22B, same as forward rotation, if the rotational angular velocity reaches a certain value, the second protrusion 232 engages with the step 123b on the thin-walled side under the action of centrifugal force 'F', thereby making the eccentric sleeve 120 and the key The parts 130 are in a multi-point contact state. As in the case of clockwise rotation, the stable engagement of the first protrusion 231 enables smooth engagement of the second protrusion 232 and the eccentric sleeve 120 . Therefore, at the time of reverse rotation, even if there is an external force 'P' acting on the piston by the pressure of the working fluid at the time of compression and any other force received, it is possible to prevent the gap between the crankpin 110 and the eccentric sleeve 120 from being reversed. relative rotation occurs. In addition, as shown in FIG. 22B, during reverse rotation, since the eccentric sleeve 120 is set to have the maximum eccentricity, the piston reciprocates within the maximum stroke length Lmax, thereby enabling the compressor of the present invention to have maximum Compression capacity.

In conclusion, relative movement between the crank pin 110 and the eccentric sleeve 120 is very well eliminated by using the key member 130, so that the compressor of the present invention operates stably. In addition, the key part 230 prevents the eccentric sleeve from rotating by the eccentric force 'C' and the rotational moment 'M', thereby ensuring operational reliability.

On the other hand, in order to prevent the second protrusion 132 from being engaged in an unstable manner, it has been proposed above with reference to FIGS. The key member 130 is prevented from disengaging. As described above, since the center of gravity 'G' is biased towards the restricting portion 122, the rotational moment 'M' is well generated before the key member 130 catches the eccentric sleeve 120 in the subsequent rotation. In order to move the position of the center of gravity 'G', it is necessary to increase the weight of the lighter portion of the eccentric sleeve 120 . The counterweight has an appropriate weight for shifting the center of gravity, and is provided on the track portion 121 on the lighter side of the eccentric sleeve. The counterweight 127 may be integrally formed with the eccentric sleeve, or may be mounted to the eccentric sleeve 120 as a separate component.

25A and 25B are plan views showing the relationship of forces generated when the eccentric sleeve 120 with the counterweight 127 is rotated clockwise and counterclockwise, respectively.

As shown, the counterweight 127 is preferably capable of offsetting the center of gravity "G1" of the eccentric sleeve to the plane of the crankshaft axis 23a and the crankpin axis 110a. The center of gravity "G1" enables the centrifugal force 'F' of the crankshaft 23/crankpin 110 and the centrifugal force 'C1' of the eccentric sleeve 120 to act in the same direction. Therefore, since there is no moment arm between the center of gravity "G1" and the crankpin axis 110a, no rotational moment is generated whether the rotation is clockwise (FIG. 25A) or counterclockwise (FIG. 25B), and Since there is no rotational moment, rotation is essentially prevented.

In addition, the counterweight 127 shifts the center of gravity 'G2' of the eccentric sleeve 120 from the original center of gravity 'G' to an opposite position with respect to the plane where the crankshaft axis 23a and the crankpin axis 110a lie. In this way, the center of gravity 'G2' generates a rotational moment 'M2' which is opposite to the rotational direction of the centrifugal force 'C2'. That is, as shown in Figure 25A, when the crankshaft rotates clockwise, the center of gravity 'G2' produces a counterclockwise rotational moment 'M2', and as shown in Figure 25B, when the crankshaft rotates counterclockwise, the center of gravity ' G2' produces a clockwise rotational moment 'M2'. The rotational moment 'M' acts together with the frictional force 'f' to rotate the eccentric sleeve 120 in a direction opposite to the rotational direction. Accordingly, the first protrusion 131 is stably engaged with the eccentric sleeve 120 , thereby continuously and smoothly engaging the second protrusion 132 with the eccentric sleeve 120 .

In summary, similar to the key member 230 in the second embodiment, the counterweight 127 prevents the disengagement of the eccentric sleeve 120 from the key member 130 due to the centrifugal force 'C'/rotational moment 'M', thereby improving the compression of the present invention. machine stability. Although only the counterweight 127 is described in combination with the key member 130 of the first embodiment, the counterweight 127 can also be used with the key member 230 of the second embodiment.

It will be apparent to those skilled in the art that various modifications and variations can be made in the dual capacity compressor of the present invention without departing from the spirit or scope of the invention. Accordingly, the present invention is protected for all modifications and variations of the present invention that come within the scope of the appended claims and their equivalents.

Industrial Applicability

The multi-point contact between the eccentric sleeve and the key part during operation allows the key part to securely hold the crank pin and the eccentric sleeve. Accordingly, relative movement between the eccentric sleeve and the crank pin can be prevented regardless of internal or external causes, thereby allowing the compressor to operate stably without any output variation. That is, a fixed compression capacity is obtained by maintaining a fixed eccentricity. Furthermore, frictional losses between the crank pin and the eccentric bush due to relative movements are prevented. Finally, such stable operation results in an increase in the efficiency of the dual capacity compressor. In addition, it prevents noise due to relative movement and prolongs the service life of components.

In addition, there is a change in the part that was initially caught between the key member and the eccentric sleeve, or the center of gravity of the eccentric sleeve is shifted due to the use of a counterweight. Therefore, even before the eccentric sleeve is well locked by the key member, the eccentric sleeve does not rotate under the action of centrifugal force and rotational moment. The key part can thus engage the eccentric sleeve very well and stably, thereby increasing the stability of the compressor.

By using the elastic member to properly limit the movement of the key part under the action of centrifugal force, the compressor of the present invention can avoid using too many parts to realize this function. Therefore, the construction of the present invention becomes substantially simplified, and assembly becomes easy, thereby improving productivity.

Claims (41)

1. A dual capacity compressor comprising: A power generating component comprising a reversible electric motor and a crankshaft inserted into the electric motor; a compression component comprising a cylinder, a piston positioned within the cylinder, and a connecting rod connected to the piston; a crankpin positioned on the upper portion of the crankshaft and eccentrically relative to the axis of said crankshaft; an eccentric sleeve, the eccentric sleeve has an inner peripheral surface and an outer peripheral surface, the inner peripheral surface is rotatably installed in the outer peripheral surface of the crankpin, and the outer peripheral surface of the eccentric sleeve is rotatable way mounted to one end of the connecting rod; and a key member configured such that the key member engages with a portion of the eccentric sleeve and is also retained on the eccentric sleeve during operation so as to rigidly couple the eccentric sleeve in all directions of rotation of the motor Sleeves and crankpins; Wherein, the key component further includes an elastic member for supporting the key component, and regardless of the operating state of the compressor, the elastic component always supports at least a part of the continuous protrusion of the key component to pass through the crank pin , Multiple compression capacities are provided by rearranging the eccentric sleeve based on multiple eccentricities and piston displacements as the direction of motor rotation changes, virtually preventing the crankpin and eccentric sleeve through the keying regardless of the direction of motor rotation The relative movement of the barrel during operation, Wherein, the eccentric sleeve also includes a balance weight, which rotates together with the eccentric sleeve to shift the center of gravity of the eccentric sleeve during the rotation and maintain the balance between the eccentric sleeve and the key component. joint between. 2. The dual capacity compressor of claim 1, wherein the key member engages the eccentric sleeve at multiple points. 3. The dual capacity compressor of claim 1, wherein the key member is engaged with the eccentric sleeve at two points disposed in arbitrary directions with respect to the center line during operation. 4. The dual capacity compressor of claim 1, wherein the key member has a length greater than an outer diameter of the crank pin. 5. The dual capacity compressor according to claim 1, wherein the key member is always engaged with at least a portion of the eccentric sleeve located oppositely at a radially inner portion of the crankshaft. 6. The dual capacity compressor of claim 1, wherein said key member comprises: a first protrusion protruding outside the crankpin by a first predetermined length; and The second protrusion protrudes outside the crankpin by a second predetermined length only during operation. 7. The dual capacity compressor according to claim 6, wherein the first protrusion protrudes through the crankpin all the way inward in the radial direction. 8. The dual capacity compressor of claim 1, wherein the key member prevents the eccentric sleeve from being rotated due to a centrifugal force acting on the eccentric sleeve and a corresponding rotational moment. 9. The dual capacity compressor according to claim 1, wherein the key member is always engaged with at least a part of the eccentric sleeve, thereby making the direction of the rotational moment generated by the eccentric sleeve consistent with the direction of the eccentric sleeve. The direction of rotation of the crankshaft is opposite. 10. The dual capacity compressor according to claim 1, wherein the key member is always engaged with at least a portion of the eccentric sleeve located oppositely at a radially outer portion of the crankshaft. 11. The dual capacity compressor of claim 1, wherein said key member comprises: a first protrusion protruding through the crankpin to the outside of the crankpin; and A second protrusion protrudes through the crank pin to the outside of the crank pin and engages with the eccentric sleeve during operation of the compressor. 12. The dual capacity compressor of claim 11, wherein the first protrusion protrudes to an outer side of the crankshaft in a radial direction. 13. The dual capacity compressor of claim 11, wherein the second protrusion protrudes through the crank pin such that the second protrusion is not eccentric to the compressor when the compressor is stationary. The sleeve interferes. 14. The dual capacity compressor of claim 11, wherein the second protrusion includes a groove for passing the eccentric sleeve when the compressor is at rest. 15. The dual capacity compressor of claim 1, wherein said key member includes a stopper within said crankpin to limit movement of said key member relative to said crankpin. 16. The dual capacity compressor of claim 15, wherein a contact surface of the stopper coincides with a corresponding inner peripheral surface of the crank pin. 17. The dual capacity compressor of claim 15, wherein the stopper includes a first stopper that restricts movement of the key member in the first direction. 18. The dual capacity compressor of claim 17, wherein the stopper further comprises a second stopper restricting movement of the key member in a second direction opposite to the first direction. 19. The dual capacity compressor as claimed in claim 1, wherein the elastic member restricts movement of the key member in the first direction. 20. The dual capacity compressor as claimed in claim 1, wherein the elastic member provides uneven elastic force. 21. The dual capacity compressor as claimed in claim 1, wherein the elastic force of the first portion of the elastic member is relatively greater than the elastic force of the second portion of the elastic member. 22. The dual capacity compressor as claimed in claim 1, wherein an elastic force of a part of the elastic member is greater than a centrifugal force generated by the key member. 23. The dual capacity compressor of claim 1, wherein the elastic member comprises: a first elastic member in contact with the key member; and A second elastic member in contact with the first elastic member and the inner peripheral surface of the crank pin respectively, wherein the elastic force of the second elastic member is greater than that of the first elastic member. 24. The dual capacity compressor as claimed in claim 23, wherein an elastic force of the second elastic member is greater than a centrifugal force generated by the key member. 25. The dual capacity compressor of claim 23, wherein said first elastic member is a spring having a first diameter and said second elastic member extends from said first elastic member and has a diameter greater than The diameter of the first elastic member is a spring of a second diameter. 26. The dual capacity compressor as claimed in claim 1, wherein the crank pin includes a pair of key fitting portions disposed opposite to each other. 27. The dual capacity compressor as claimed in claim 26, wherein the key fitting portion includes a through hole formed in a wall of the crank pin. 28. The dual capacity compressor as claimed in claim 26, wherein the key fitting portion includes at least one groove extending from the top end of the wall of the crank pin to a predetermined position of the wall. 29. The dual capacity compressor of claim 1, wherein said eccentric sleeve comprises: a track portion formed along the extending direction of the main body itself of the eccentric sleeve for allowing the protrusion of the key member to rotate; and A restricting portion formed with respect to the rail portion for restricting rotation of the protrusion of the key member. 30. The dual capacity compressor as claimed in claim 29, wherein the track portion of the eccentric sleeve includes a track portion extending from a top end of the eccentric sleeve to a predetermined depth and extending in a circumferential direction of the eccentric sleeve. cut off part. 31. The dual capacity compressor of claim 29, further comprising a step disposed between the track portion and the restricting portion, wherein the step is parallel to the longitudinal axis of the crankshaft and the longitudinal direction of the crankpin The plane on which the axis lies. 32. The dual capacity compressor of claim 29, further comprising a step disposed between the track portion and the restricting portion, wherein the step is in a plane with the longitudinal axis of the crankshaft and the longitudinal axis of the crankpin, respectively. Space half the thickness of the key parts. 33. The dual capacity compressor of claim 29, further comprising a step disposed between the track portion and the restricting portion, wherein at least one of the steps is aligned with the longitudinal axis of the crankshaft and the longitudinal direction of the crankpin. Half the thickness of the key member is inclined in such a way that the plane of the axis is at an angle. 34. The dual capacity compressor of claim 1, wherein the eccentric sleeve further comprises a ring disposed between a bottom surface of the eccentric sleeve and a top surface of the crankshaft. 35. The dual capacity compressor of claim 1, wherein the balance weight prevents rotation of the eccentric sleeve due to a rotational moment. 36. The dual capacity compressor of claim 1, wherein said counterweight prevents rotational moment generated by said eccentric sleeve. 37. The dual capacity compressor of claim 1, wherein said counterweight locates a center of gravity of said eccentric sleeve in a plane in which a longitudinal axis of said crankshaft and a longitudinal axis of said crankpin lie. 38. The dual capacity compressor of claim 1, wherein the counterweight generates a rotational moment in a direction opposite to the rotational direction. 39. The dual capacity compressor of claim 1, wherein said counterweight shifts the center of gravity of said eccentric sleeve to opposite sides with respect to the plane in which the longitudinal axis of said crankshaft and the longitudinal axis of said crankpin lie. s position. 40. The dual capacity compressor of claim 1, wherein said counterweight is disposed on a relatively light portion of said eccentric sleeve. 41. The dual capacity compressor of claim 29, wherein said counterweight is disposed on said track portion of said eccentric sleeve.

Images