JP5469612B2 - Rotary fluid machinery - Google Patents

Description

  The present invention relates to a rotary fluid machine mounted on a refrigeration air conditioner or the like.

  In recent years, the need for downsizing of the compressor is increasing from the viewpoint of environmental load reduction and cost. Taking an air conditioner as an example, the cylinder volume of the mounted compressor is adjusted in accordance with the refrigeration capacity of the air conditioner. Here, the compressor mounted on the compressor is combined in an optimal manner by changing the external dimensions of the compressor for each required cylinder volume. For example, when developing a compressor with a small cylinder volume, the current product is similar. It was common to design by a method of reducing the size. Conversely, when the cylinder volume is increased, it is inevitable to increase the diameter of the compressor. For example, the relationship between the cylinder volume of an existing rotary compressor and the outer diameter of the compressor is approximately φ90 for approximately less than 10 cc and approximately φ110 for approximately 8 to 18 cc.

  In addition, there is an increasing need to switch to a natural refrigerant for the purpose of preventing global warming, and when using tetrafluoropropene, such as HFO1234yf, as an alternative to the R410A refrigerant currently used in air conditioners, It is also known that the refrigerant circulation amount required for the refrigeration cycle is approximately doubled due to the difference in refrigerant physical properties, and it is necessary to increase the cylinder volume or the operating frequency in the compressor when using the same cycle.

  Regarding the downsizing of the compressor outer diameter, a technique disclosed in Patent Document 1 is known as a conventional technique.

Japanese Patent Laid-Open No. 2001-50184

  In response to the above background, it is necessary to develop a compressor capable of maintaining the capacity of the refrigeration air conditioner and reducing the outer diameter of the compressor or expanding the capacity of the refrigeration air conditioner and maintaining the outer diameter of the compressor. And faced the following challenges:

  As a first problem, there is a balance between maintaining the capacity of the refrigeration air conditioner and the performance and reliability of the compressor. When the cylinder volume is reduced together with the outer diameter of the compressor as in the prior art, the capacity can be maintained by increasing the operating frequency of the compressor, but if this operating frequency becomes excessive, the compression mechanism section This is a factor that hinders performance such as efficiency reduction and noise increase due to an increase in mechanical loss in the sliding part. At the same time, since the compression work increases, the load on the sliding portion such as the bearing portion increases, making it difficult to ensure reliability. For this reason, an increase in the operating frequency of the compressor naturally causes a limit point, and it is necessary to devise a compression mechanism portion that can reduce only the outer diameter in order to secure the cylinder volume.

  As a second problem, it is necessary to secure a space volume in the compressor hermetic container. The lower part of the sealed container in which the compression mechanism part is accommodated is mainly used for lubrication or cooling of the sliding part of the compression mechanism part in a space formed by the inner wall of the sealed container and the outer wall of the compression mechanism part. It is necessary to store refrigeration oil. The liquid level height from the bottom of the compressor of the refrigerating machine oil in the sealed container determined by the storage amount of the refrigerating machine oil has an appropriate position for ensuring the performance and reliability of the compressor. When the liquid level is excessive, the motor is stirred by the rotational movement of the motor part provided in the upper part of the sealed container, the efficiency is reduced due to the loss of compressor power, and the refrigeration cycle is brought out of the chiller oil out of the sealed container. This causes a heat exchange hindrance and pressure loss, resulting in a decrease in efficiency and a decrease in reliability due to a shortage of refrigerating machine oil in the compressor. On the other hand, if the liquid level is too small, a sufficient amount cannot be supplied to the vane sliding portion of the cylinder that requires oil supply from the side surface of the compression mechanism, leading to a decrease in reliability. Here, since the refrigerating machine oil is mixed with the refrigerant in the refrigerating cycle and diluted to cause a decrease in viscosity, the amount of refrigerating machine oil to be stored must be maintained. For this reason, when the compressor diameter is reduced or the cylinder volume is increased, the space volume for storing the refrigerating machine oil becomes smaller and the liquid level of the refrigerating machine oil tends to be excessive, so that it is necessary to secure the space volume.

To achieve the above object, according to the present invention, a container is provided with a crankshaft having an eccentric portion, a compression mechanism portion driven by the eccentric portion, and a closing member for closing the compression mechanism portion in the crankshaft direction. The compression mechanism portion includes a cylinder, a roller disposed in the cylinder and driven to rotate by the eccentric portion, a closing member for closing the cylinder in the axial direction, and an outer periphery of the roller. In a rotary fluid machine having a vane that enters and exits a storage portion provided in the cylinder according to the eccentric motion of the cylinder and a spring that presses the vane against a roller, the cylinder is sealed with refrigeration oil between the container and the inner wall of the container. An outer peripheral portion of a substantially circular cylinder that forms a space to be closed, and a vane storage portion outer wall provided with a vane storage portion that stores the vane, the cylinder The substantially throughout the circular cylinder outer peripheral portion definitive, characterized in that a plurality of recesses.

Another feature of the present invention is that in the above rotary fluid machine, instead of providing a plurality of recesses over the substantially circular cylinder outer peripheral portion of the cylinder, the entire outer peripheral portion of the closing member is provided. A plurality of recesses are provided.
According to still another aspect of the present invention, in the rotary fluid machine described above, the closing member is used to engage the compression mechanism with the container, and the cylinder and the entire outer periphery of the closing member. Is provided with a recess.

Here, in consideration of strength and sealing properties necessary for forming a compression mechanism, the plurality of recesses are formed with respect to a plurality of holes provided in the range from the inner wall to the outer peripheral portion constituting the compression chamber of the cylinder. ,
(Minimum distance between the recess and the cylinder inner wall ) ≧ (Minimum distance between the cylinder inner wall and the hole) ≧ 2.5 mm
Or (minimum distance between the recess and the hole) ≧ (minimum distance between the cylinder inner wall and the hole) ≧ 2.5 mm
It is better to configure to satisfy .

According to the present invention, Runode can refrigerating machine oil is formed by an outer circumference of the container inner wall and the cylinder or closure member to expand the volume of the space to be sealed, the sealed container into the cylinder capacity of the compression mechanism portion As a result, the compressor can be designed in such a manner that the space required for optimizing the liquid level at the time of filling the refrigeration oil is ensured.

Sectional drawing of the compression mechanism part periphery by this invention. Sectional drawing of the compression mechanism part periphery by a prior art. Refrigerator oil liquid level height comparison sectional view accompanying diameter reduction of a compressor.

  Examples according to the present invention will be described below.

  As an embodiment of the present invention, a rotary compressor for an air conditioner having the following structure will be described as an example. A motor part is housed in a sealed container, a crankshaft having an eccentric part for transmitting the rotation of the motor part, a compression mechanism part driven by the eccentric part, and a closure for closing the compression mechanism part in the crankshaft direction A member, and the compression mechanism section includes a cylinder, a roller disposed in the cylinder and driven to rotate by an eccentric portion of the crankshaft, and extends to an outer periphery of the roller according to the eccentric motion of the roller. It is comprised by the vane which goes in and out of the accommodating part provided in the cylinder, and the spring which presses the said vane to a roller, and is accommodated in the lower part of the motor part in the said airtight container. The closing member includes a bearing for holding the crankshaft, and includes an upper bearing and a lower bearing for closing the upper and lower sides of the cylinder, or a partition plate when there are a plurality of the compression mechanism portions, and a compression chamber in the compression mechanism portion. A discharge hole for discharging the compressed gas into the sealed container is provided in the upper bearing or the lower bearing. The compression mechanism part is single or plural, and the refrigerating machine oil whose main purpose is lubrication or cooling of the sliding part of the compression mechanism part is provided in the sealed container.

  FIG. 1 is a sectional view around a compression mechanism as an embodiment of the present invention, and FIG. 2 is a sectional view around a compression mechanism according to the prior art. Here, an example is given in which the diameter of the compressor is reduced while maintaining the cylinder volume of the compression mechanism, and the inner diameter of the sealed container 50 in each compressor is φ80 in FIG. In FIG. 2, the form is described as φ112. In each figure, a cylinder 10 includes a cylinder inner wall 11, a substantially circular cylinder outer wall 12, a vane storage portion 13 for storing a vane 30 that partitions the compression chamber 20 into a low pressure side and a high pressure side, a vane storage portion outer wall 14, and the cylinder inner wall. 11 and the cylinder outer wall 12 have a plurality of holes 15 such as a hole 15a used for fastening a closing member for each application, a hole 15b used as a fluid flow path, a hole 15c used as a reference during processing, and the like. Is formed of a suction hole 16 for taking the gas into the cylinder inner wall 11. The compression chamber 20 is formed by the cylinder inner wall 11 and the outer wall of the roller 40, and the volume of the compression chamber 20 in the state shown in the figure becomes the cylinder volume of the compressor. The vane 30 is pressed toward the center of the inner wall of the cylinder by a spring in order to ensure contact with the outer wall of the roller 40 that is eccentrically moved by the crankshaft. Here, the compression chamber 20 in each figure has the same cylinder volume by making the diameter φ43 of the cylinder inner wall 11 and the outer wall diameter of the roller 40 equal, and an air conditioner at the same operating frequency. The ability to equalize has been achieved. Further, in order to secure a region for forming a plurality of holes 15 for fastening with the closing member or as a fluid flow path, the average diameter φ69 of the substantially cylindrical outer wall 12 is also set to the same value. As described above, the inner diameter of the sealed container 50 is φ80 in the embodiment of the present invention and φ112 in the prior art, and the diameter of the outer wall 14 of the vane housing portion of the cylinder is substantially equal to the inner diameter of the sealed container.

  The cylinder 10 according to the prior art shown in FIG. 2 has a protrusion 17 having the same diameter as the vane storage portion outer wall 14 in a direction substantially shifted by 180 ° from the vane storage portion outer wall 14 of the cylinder and the vane storage portion 13 of the cylinder. Is provided. The outer wall 14 and the protrusion 17 of the vane storage portion are used for the purpose of engaging the sealed container 50 and the compression mechanism portion 100 by welding (point 18) or shrink fitting or cold fitting. Therefore, the diameters of the vane storage portion outer wall 14 and the protrusion 17 need to be larger than the diameter of the cylinder inner wall 11 in order to suppress deformation of the cylinder inner wall 11 due to welding heat or fastening stress. On the other hand, in the embodiment of the present invention, the vane is formed by applying an engagement between the sealed container 50 and the compression mechanism 100 by welding, shrink fitting, cold fitting or the like to an upper bearing which is one of the closing members 60. The diameter of the storage section outer wall 14 can be set to a minimum diameter that allows the vane storage section to be disposed and has a size that can withstand the load caused by the movement of the vanes, and the diameter of the sealed container can be reduced.

However, since the refrigerating machine oil 70 is sealed in the space 51 in the sealed container represented by the hatched portion formed by the inner wall of the sealed container 50 and the outer shape of the cylinder 10, this space 51 needs to guarantee a certain volume. There is. Since the required amount of the refrigeration oil 70 is determined by the amount of refrigerant corresponding to the cycle capacity of the air conditioner, in order to maintain the performance of the air conditioner, the amount of the refrigeration oil enclosed is reduced simultaneously with the diameter reduction of the compressor. It is difficult to reduce the reliability. For this reason, when the inside diameter of the sealed container 50 is made small, if the same amount of the refrigerating machine oil 70 is sealed, the refrigerating machine oil 70 flows in the axial direction of the compressor. It becomes difficult to set the liquid level height to the upper end of the compression mechanism unit, which is the upper limit. In this way, if the diameter of only the sealed container 50 is reduced while maintaining the cylinder volume of the compressor to ensure the capacity of the refrigeration air conditioner, the ratio of the diameter of the cylinder 10 to the inner diameter of the sealed container 50 increases. Therefore, the space 51 is reduced, and in particular, the inner diameter of the sealed container 50 and the inner diameter of the cylinder 10 are (the inner diameter of the cylinder) / (the inner diameter of the sealed container) ≧ 0.4.
In such a case, it is difficult to ensure the liquid level.

  FIG. 3 shows a comparison between the inner diameter of the sealed container 50 and the height of the liquid surface 71 due to the difference in the length of the sealed container 50 or the crankshaft 80, using a longitudinal sectional view of the compressor. Here, an example in the case of having two compression mechanism sections 100 is shown, and a partition plate 62 for closing the lower end of the cylinder 10a on the inner motor section 90 side of the cylinder 10 and the upper end of the cylinder 10b on the bottom face side of the compressor is provided. ing. Here, the liquid surface 71 has a lower limit as a lower end 71a of the cylinder 10a because the sealing performance and the lubricity with the vane 30 are increased by performing oil supply to the vane storage portion 13 from the side surface of the cylinder 10, In order to reduce the influence of agitation and the like due to the rotation of the electric motor unit 90, the upper limit is set to the upper end 71b of the cylinder 10 to obtain an appropriate position. FIG. 3A is a longitudinal sectional view when the inner diameter of the sealed container 50 according to the prior art is φ112. FIG. 3B is a longitudinal sectional view when the inner diameter of the sealed container 50 is set to φ80 using the above-described method, and the liquid level 71 exceeds the upper end 71b of the cylinder which is the upper limit. In contrast to the state shown in FIG. 3B, in the prior art, as shown in a longitudinal sectional view of FIG. Although attempts have been made to lower it to an appropriate position, extension of the sealed container 50 and extension of the crankshaft 80 for securing the oil supply passage are necessary, and it has been difficult to achieve sufficient resource saving.

  Therefore, in the embodiment of the present invention, a plurality of recesses 19 are provided in the cylinder outer wall 12 as shown in FIG. As a result, the space 51 can be expanded without extending the closed container 50 or the crankshaft 80, which is a conventional technique, which is effective in reducing the height of the liquid level 71. However, since a pressure difference is generated between the space 51 and the compression chamber 20 by the high pressure gas equivalent to the approximate discharge pressure and the low pressure gas equivalent to the approximate suction pressure, a thickness to suppress leakage is required. The setting of 19 requires the following conditions.

The conditions for preventing leakage due to the pressure difference will be described. The pressure in the space 51 is, for example, a high-pressure gas in the case of a high-pressure chamber system, and the fluid passage hole 15b of the hole 15 is also filled with a substantially equivalent high-pressure gas. On the other hand, the pressure in the compression chamber 20 is discharged from the low pressure gas at the suction pressure and filled with the high pressure gas at the pressure according to the compression process. In the conventional compressor, a distance is secured between the hole 15b and the cylinder inner wall 11 to prevent leakage due to the pressure difference, so that the recess 19 serving as the wall surface of the space 51 and the outer wall of the compression chamber 20 are formed. The distance between the cylinder inner walls 11 is based on the distance between the hole 15b and the cylinder inner wall 11,
By setting the condition of (distance between the recess 19 and the cylinder inner wall 11) ≧ (distance between the hole 15b and the cylinder inner wall 11), leakage between the recess 19 and the cylinder inner wall 11 can be prevented. In the low-pressure chamber system, the space 51 is filled with low-pressure gas and the distance between the recess 19 and the hole 15b is set to prevent leakage between the holes 15b.
(Distance between recess 19 and hole 15b) ≧ (Distance between hole 15b and cylinder inner wall 11)
Is a condition. Here, as a result of experimentally obtaining specific numerical values (distance between the hole 15b and the cylinder inner wall 11) as the criteria for setting each of the above conditions, it is necessary to set at least 2.5 mm or more. In the present embodiment, the method for setting the recesses in the cylinder 10 has been described. However, it is possible to provide the upper bearing 61, the partition plate 62, and the lower bearing 63 as the closing member 60 by the same setting method. .

  The concave portion 19 that satisfies the above conditions does not necessarily need to be provided by machining, and setting at the material stage is effective in reducing the material weight, that is, the cost. By setting the recess 19 as described above, the height of the liquid level 71 in FIG. 3B can be set to the upper end 71b of the cylinder, which is the upper limit. FIG. 3D is a longitudinal sectional view according to the embodiment of the present invention.

  Further, the suppression of the increase in the outer diameter of the compressor due to the expansion of the cylinder volume, which is necessary when the above-described alternative refrigerant HFO1234yf is applied, can be handled by using the same method as described above.

  Based on the above, it is possible to design a compressor that has a minimum required outside diameter relative to the cylinder volume of the compressor, and that secures the space necessary for optimizing the liquid level when filling refrigeration oil as the outside diameter is reduced Thus, a compact, highly efficient and reliable compressor can be provided.

  In the present embodiment, the example in which the concave portion 19 is set to the substantially circular cylinder outer wall 12 has been described. However, the present invention is not limited to this. For example, the concave portion 19 can be applied to the vane storage portion outer wall 14. it can.

DESCRIPTION OF SYMBOLS 10 ... Cylinder, 11 ... Cylinder inner wall, 12 ... Cylinder outer wall, 13 ... Vane storage part, 14 ... Vane storage part outer wall, 15 ... Hole set between cylinder inner wall and cylinder outer wall, 16 ... Fluid, such as a refrigerant | coolant, said A suction hole to be taken into the cylinder inner wall 11, 17... A projection positioned at approximately 180 ° with respect to the vane storage portion, 18. 20 ... Compression chamber formed by cylinder inner wall and roller outer wall, 30 ... Vane, 40 ... Roller, 50 ... Sealed container of compressor, 51 ... Space formed by cylinder outer wall and sealed container inner wall, 60 ... Closure member, 61 ... Upper bearing, 62 ... Partition plate, 63 ... Lower bearing, 70 ... Refrigerating machine oil, 71 ... Liquid level when the refrigerating machine oil is enclosed in the compressor, 80 ... Crankshaft, 90 ... Electric motor part, 1 0 compression mechanism.

Claims (11)

In the container, a crankshaft having an eccentric portion, a compression mechanism portion driven by the eccentric portion, and a closing member that closes the compression mechanism portion in the crankshaft direction are provided.
The compression mechanism section includes a cylinder, a roller disposed in the cylinder and driven to rotate by the eccentric section, a closing member that closes the cylinder in the axial direction, and an outer periphery of the roller. In a rotary fluid machine having a vane that enters and exits a storage portion provided in the cylinder according to an eccentric motion, and a spring that presses the vane against a roller,
The cylinder includes a substantially circular cylinder outer peripheral portion that forms a space in which refrigeration oil is sealed between the container inner wall and a vane storage portion outer wall provided with a vane storage portion that stores the vane.
A rotary fluid machine characterized in that a plurality of recesses are provided over the entire outer circumference of the substantially circular cylinder in the cylinder . The rotary fluid machine according to claim 1, wherein instead of providing a plurality of recesses over the entire outer periphery of the substantially circular cylinder in the cylinder, a plurality of recesses are provided over the entire outer periphery of the closing member. A rotary fluid machine characterized by being provided. In the rotary fluid machine according to claim 1, with the closing member, the compression mechanism portion engaged with said container, provided with a plurality of recesses and over the entire outer periphery of said cylinder and said closure member A rotary fluid machine characterized by the above. 4. The rotary fluid machine according to claim 1, further comprising: a plurality of holes provided in a range from an inner wall to an outer peripheral portion constituting a compression chamber of the cylinder; and (the concave portion and the hole). Minimum distance) ≧ (minimum distance between the cylinder inner wall and the hole)
A rotary fluid machine characterized by being configured as follows . 4. The rotary fluid machine according to claim 1, wherein a plurality of holes are provided in a range from an inner wall constituting the compression chamber of the cylinder to an outer peripheral portion, and (a minimum between the cylinder inner wall and the concave portion). Distance) ≧ (Minimum distance between the cylinder inner wall and the hole)
A rotary fluid machine characterized by being configured as follows . 4. The rotary fluid machine according to claim 1, wherein a plurality of holes are provided in a range from an inner wall constituting the compression chamber of the cylinder to an outer peripheral portion, and (a minimum between the cylinder inner wall and the concave portion). Distance) ≧ 2.5mm
A rotary fluid machine characterized by being configured as follows . The rotary fluid machine according to any one of claims 1 to 3, wherein a plurality of holes are provided in a range from an inner wall constituting the compression chamber of the cylinder to an outer peripheral portion, and (a minimum distance between the concave portion and the hole). ) ≧ 2.5mm
A rotary fluid machine characterized by being configured as follows . The rotary fluid machine according to any one of claims 1 to 3,
(Cylinder inner diameter) / (Container inner diameter) ≧ 0.4
A rotary fluid machine characterized by the above. The rotary fluid machine according to any one of claims 1 to 3,
A rotary fluid machine using tetrafluoropropene as a working fluid. The rotary fluid machine according to any one of claims 1 to 3,
A rotary fluid machine using HFO1234yf as a working fluid. The rotary fluid machine according to any one of claims 1 to 3,
(Inner diameter) ≤ 90mm
A rotary fluid machine characterized by the above.

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