KR20030047546A - Multi capacity compressor - Google Patents

Abstract

PURPOSE: A multi-capacity compressor is provided to adjust discharge amount in various sizes even in the equal Lmin and Lmax of a piston by being variously changed into the volume of a cylinder. CONSTITUTION: A multi-capacity compressor comprises a power generating unit(20) having a motor and a crank shaft(23) inserted into the motor, a compressing unit(30) including a predetermined-size cylinder(32), a piston(31) located in the cylinder, and a connecting rod(33) of which both ends are connected with the piston and a crank pin of the crank shaft respectively, and a compression capacity varying device installed to the cylinder to change the volume of the cylinder.

Description

MULTI CAPACITY COMPRESSOR}

The present invention relates to a compressor for compressing a working fluid such as a refrigerant to a predetermined pressure, and more particularly to a compressor for changing the compression capacity as needed.

In various devices that require compression of the working fluid, in particular in home appliances using refrigeration cycles such as refrigerators, the size of the load actually changes from time to time, and the compression capacity of the compressor changes depending on the size of the load to improve the operating efficiency. Required. Various technical attempts have been made to solve such compressor capacity changes, and as an example, a double capacity compressor may be used. This double displacement compressor has two compression capacities as the motor rotates forward and backward, the most common of which is disclosed in US Pat. No. 4,236,874.

1 is a cross-sectional view showing the structure of a double displacement compressor according to US Patent No. 4,236,874, and FIG. 2 is a schematic view showing the operation of the double displacement compressor.

The main part of the double displacement compressor, as shown, is a piston 7 inside the cylinder 8, a crankshaft 1, and a crank pin 3 in which the center 3a is eccentrically formed with the center 1a of the crankshaft. ), And an eccentric ring 4 coupled to the crank pin 3, and a connecting rod 6 connected to the eccentric ring 4 and the piston 7, respectively. The eccentric ring 4 and the connecting rod 6 are rotatable with respect to an adjacent component and have the center of rotation of the crank pin center 3a. On each contact surface of the crank pin 3 and the eccentric ring 4, a release region 9 of a predetermined length is formed, and in the release region 9, the crank pin 3 and the eccentric ring 4 are connected to each other. A key 5 for engagement is provided. The operation according to the compression capacity of the double displacement compressor is as follows. As shown in FIG. 2, in the double displacement compressor, the stroke distance of the piston 7 is adjusted by the amount of eccentricity that varies according to the arrangement state of the eccentric ring 4, and when a large load is required, the crankshaft ( 1) clockwise (forward direction), when the load is required to be small, the crankshaft 1 is rotated counterclockwise (reverse direction). More specifically, FIG. 2A shows a state where the piston 7 is located at the top dead center and B is the bottom dead center during the clockwise rotation, and in this case, the eccentricity is the maximum, so the stroke distance Lmax. Is also the maximum. In addition, FIG. 2C shows a state where the piston 7 is located at the bottom dead center, and D is the top dead center of the piston, and the stroke distance Lmin is minimized due to the minimized amount of eccentricity.

However, due to the rotation about the crankshaft center 1a during this operation, a separate centrifugal force acts on the crank pin 3 and the eccentric ring 4, and this centrifugal force is generated between the axis center 1a and the pin center 3a. And an extension line between the shaft center 1a and the ring center of gravity 4a, respectively. Therefore, unlike A and B of FIG. 2, since the lines of action do not coincide with each other, the eccentric ring 4 has a vertical distance d with respect to the pin 3 and the product of its centrifugal force. The local moment of rotation which occurs appears and the direction of action of this moment of rotation is the same as the direction of rotation of the crankshaft 1 (counterclockwise). Since the crank pin 3 and the eccentric ring 4 are members rotatably separated from each other, the rotation moment causes relative rotation in the direction of rotation of the crank shaft 1 so that the key 5 is moved to the crank pin 3 and Release from eccentric ring (4). The eccentric ring 4 and the key 5 are thus moved in the rotational direction as indicated by the dashed line in FIG. 3. Further, as shown in FIG. 3, for example, the pressure P in the cylinder (re-expansion pressure of the working fluid) after the compression process during operation in the clockwise direction causes the eccentric ring 4 to rotate in the crankshaft 1 direction. Acting as a pushing force, this pressure rotates the eccentric ring 4 relative to the crank pin 3 in the direction of the compressor rotation. As a result, the relative rotation makes the operation of the compressor unstable, and the desired compression performance is not obtained. Substantially the relative rotation occurs because the key 5 does not completely secure the crank pin 3 and the eccentric ring 4. In addition, the key 5 makes a rolling motion in the release area 9 whenever the compressor rotation direction changes, thereby shortening the life due to severe wear at each contact.

As described above, the conventional double displacement compressor presents various problems due to the characteristics of the structure itself that changes the stroke such as the key or the eccentric ring in actual operation. In addition, the dual capacity compressor can adjust the compression capacity in only two stages, but in many cases, a compressor capable of adjusting the compression capacity in several stages is required.

On the other hand, in addition to the dual displacement compressor, but the rotational speed variable compressor, multi-cylinder compressor and the like has been developed to have a varying compression capacity, these are a lot of problems to be used in practice due to the increase in cost and the size of the compressor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a multi-capacity compressor which stably changes the compression capacity to various sizes.

1 is a cross-sectional view showing a general configuration of a conventional double displacement compressor.

2 is a schematic diagram illustrating the operation of the dual displacement compressor of FIG.

3 is a schematic representation of the relative rotation between crank pins and eccentric sleeves generated during operation of a double displacement compressor;

4 is a cross-sectional view showing the overall configuration of a multi-capacity compressor according to the present invention.

5A and 5B are plan views illustrating a compression capacity variable apparatus of the multi-capacity compressor according to the present invention.

6A and 6B are plan views showing the operation of the multi-capacity compressor according to the present invention.

Description of the main parts of the drawing

20: power generating unit 21: stator

22: rotor 23: crankshaft

30 compression unit 31 piston

32: cylinder 33: connecting rod

34: cylinder head 35: head cover

40: variable compression capacity 41: auxiliary space

41a: through hole 42: piston

43: volume changer

In order to achieve the above object, the present invention provides a power generation unit including a motor and a crank shaft inserted into the motor; A compression unit including a cylinder having a predetermined size, a piston positioned in the cylinder, and a connecting rod having both ends connected to the crank pin of the piston and the crankshaft, respectively; And it is provided with a variable capacity compression device installed in the cylinder to change the cylinder volume, by varying the cylinder volume to provide a multi-capacity compressor in which the discharge amount is adjusted to different sizes at the same piston stroke distance.

Substantially the compression capacity variable device is formed in the upper end of the cylinder and comprises an auxiliary space of a predetermined size in communication with the inside of the cylinder and an adjusting member for changing the volume of the auxiliary space.

Here, the adjustment member is preferably a piston capable of reciprocating in the auxiliary space.

Also preferably, the adjusting member may be a volume changer which is located in the auxiliary space and whose volume changes according to the application of electricity or magnetism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention in which the above objects can be specifically realized are described with reference to the accompanying drawings. In describing the present embodiment, the same name and the same reference numerals are used for the same configuration and additional description thereof will be omitted below.

First, the overall structure of a multi-capacity compressor according to the present invention will be described with reference to FIG. 4.

As shown in the multi-capacity compressor of the present invention, the power generating unit 20 and the power generating unit 20 are positioned above the power generating unit 20 to generate and transmit the required power. Compression unit 30 for compressing the working fluid by using. In addition to this general configuration, the multi-capacity compressor further includes the compression capacity variable device 40 of FIGS. 5A and 5B installed in the compression unit 30 to change the volume of the compression unit 30. Meanwhile, the container 11 encloses the power generating unit 20 and the compression unit 30 in a sealed manner in order to prevent leakage of the refrigerant, and the frame 12 is attached to the container inside the container 11. It is elastically supported by a plurality of support members (ie springs) 14. In addition, the refrigerant suction pipe 13 and the discharge pipe 15 are respectively installed at a predetermined position of the container 11 and communicate with the inside thereof.

The power generating unit 20 is installed below the frame 12 and consists of a motor and a crankshaft 23 including a stator 21 and a rotor 22 for generating rotational force by an external power source. Here, the motor is rotatable in a counterclockwise direction, that is, clockwise and counterclockwise. The crankshaft 23 is a balance weight 23b and a balance weight 23b formed at an upper end of the drive shaft 23a and the drive shaft 23a inserted into the rotor 22 so as to transmit power. An eccentrically formed crank pin 23c is formed on the upper surface of the. In addition, the crankshaft 23 has a structure for supplying the lubricating oil accommodated in the lower part of the compressor, such as an oil hole or an oil groove, to each drive unit of the compressor.

The compression unit 30 is installed on the frame 12 to be positioned above the power generating unit 20 and has a driving mechanism mechanically moving to compress the refrigerant and an intake and discharge valve structure to assist the driving mechanism. Is done. The drive mechanism, together with the cylinder 32 forming a substantial compression space, includes a piston 31 and the crank pin 23c and the piston 31 reciprocating inside the cylinder 32 for refrigerant suction / compression. Each is connected to have a connecting rod 33 for transmitting power for reciprocating movement to the piston (31). In addition, the valve structure supplies the refrigerant to the cylinder 32 and discharges the compressed refrigerant by a combination of related parts such as the cylinder head 34 and the head cover 35.

In the dual capacity compressor configuration of the present invention, the power generation unit 20 and the compression unit 30 are the same as those of a general compressor, and thus, an additional description thereof will be omitted, and the compression capacity variable device 40 is illustrated in FIGS. With reference to 5b, it demonstrates in detail as follows.

The variable compression capacity 40 is located above the compression unit 30, that is, the cylinder 32, as shown, and adjusts the volume of the cylinder (32). To this end, the variable compression capacity 40 includes a predetermined size of the auxiliary space 41 formed in the upper end of the cylinder 32 and the adjusting members (42, 43) for changing the volume of the auxiliary space.

First, the auxiliary space 41 communicates with the inside of the cylinder through the through hole 41a. Accordingly, the refrigerant in the cylinder 32 is compressed, that is, the auxiliary space 41 during the piston 31 forward movement. ) Can flow into the interior. That is, in the present invention, the auxiliary space 41 becomes an adjustable expanded cylinder volume. More specifically, the auxiliary space 41 adjustably expands the dead volume formed when the piston 31 is located at the top dead center of the volume of the cylinder 32. A plurality of such auxiliary space 41 may be formed along the circumferential direction on the upper end of the cylinder 32 as necessary.

The adjusting members 42 and 43 may substantially change the volume of the cylinder 32 by adjusting the volume in the auxiliary space 41. This adjusting member may be a piston 42 capable of reciprocating in the auxiliary space 41 as shown in FIG. 5A. On the other hand, as shown in Fig. 5B, the predetermined volume changer 43 can be used as the adjusting member. The volume changer 43 is located in the auxiliary space 41 and is made of a material that can increase or decrease in its volume according to the application of electricity or magnetism.

Referring to the operation of the multi-capacity compressor of the present invention having such a configuration with reference to Figure 6a and 6b as follows.

When adjustment of the compression capacity is required during operation of the multi-capacity compressor of the present invention, the adjusting members 42 and 43 first change the size of the auxiliary space 41. More specifically, as shown in FIG. 6A, the piston 42 changes the size of the auxiliary space 41 by reciprocating in the auxiliary space 41. That is, the size of the auxiliary space 41 is reduced when the piston 42 is raised, and the size of the auxiliary space 41 is increased when the piston 42 is lowered. In addition, as shown in FIG. 6B, the volume changer 43 also increases or decreases the size of the auxiliary space 41 by increasing or decreasing the magnetic volume caused by the application of external current or magnetism.

Due to the change in the size of the auxiliary space 41, the volume of the cylinder 42 connected thereto is changed. More specifically, as described above, the auxiliary space 41 itself is formed near the cylinder head 34 so that the cylinder dead volume is changed. On the other hand, since the stroke distance of the piston 41 is constant, the amount of refrigerant compressed in the cylinder 31 is constant. At this time, some of the compressed refrigerant is introduced into the auxiliary space 41, so that the discharge amount of the refrigerant from the cylinder 41 through the cylinder head 34, that is, the compression capacity increases or decreases as the dead volume increases or decreases. Will decrease.

On the other hand, the auxiliary space 41 may be changed to any size by the piston 42 or the volume changer (43). Therefore, in the compressor of the present invention, the compression capacity can also be variously adjusted as necessary.

Although only a few embodiments have been described herein above, it will be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit and scope thereof. Therefore, the above-described embodiments are to be considered as illustrative and not restrictive, and thus, the invention is not limited to the above detailed description, but may vary within the scope of the appended claims and their equivalents.

As described above, the effects of the multi-capacity compressor according to the present invention will be described.

In the present invention, the compression capacity variable device forms an additional auxiliary space around the cylinder and can adjust the size of the auxiliary space by the adjustment member. Accordingly, as the size of the auxiliary space changes, the amount of compressed refrigerant flowing into the auxiliary space changes, which causes a substantial change in the discharge amount. Therefore, the compressor of the present invention can have a multi-stage compression capacity as the variable compression capacity arbitrarily adjusts the size of the auxiliary space.

On the other hand, since the configuration of the variable capacity variable compression device and other accessories are not required, the production cost can be reduced compared to other types of variable capacity compressor in the multi-capacity compressor of the present invention.

Claims (4)

A power generator including a motor and a crankshaft inserted into the motor; A compression unit including a cylinder having a predetermined size, a piston positioned in the cylinder, and a connecting rod having both ends connected to the crank pin of the piston and the crankshaft, respectively; And Compression capacity variable device is installed in the cylinder to change the volume of the cylinder, a multi-capacity compressor to adjust the discharge amount in various sizes at the same piston stroke distance by varying the cylinder volume. The method of claim 1, The compression capacity variable device: An auxiliary space formed at an upper end of the cylinder and communicating with an inside of the cylinder; And And a regulating member for changing a volume of the auxiliary space. The method of claim 2, And the regulating member is a piston capable of reciprocating in the auxiliary space. The method of claim 2, And the regulating member is a volume changer which is located in the auxiliary space and whose volume changes according to the application of electricity or magnetism.