JP4320727B2 - Gas compressor - Google Patents

Description

  The present invention relates to a vane-rotor type gas compressor that sucks and compresses gas by rotating a rotor provided with a plurality of vanes in an elliptical cylinder chamber and discharges the compressed gas.

  In this type of conventional vane / rotor type gas compressor, a discharge port is provided in the vicinity of the short diameter portion of the cylinder chamber having an elliptical cross-sectional shape, and the rotor holding the vane rotates in the cylinder chamber. When rotating around an axis, this rotating shaft is known to vibrate with a maximum amplitude in a radial direction of an angle indicated by a predetermined angle from the minor axis direction of the cylinder to the rotational direction of the rotor (for example, Patent Documents). 1).

In this way, although the rotation shaft of the rotor vibrates strongly in a specific radial direction of the cylinder chamber, the rotation shaft has a circular cross-sectional shape, so that the bearing hole of the bearing that receives the rotation shaft has a circular shape. A cross-sectional shape was adopted. Further, the hole diameter of the bearing hole is set to an appropriate value so that a sufficient gap is maintained between the rotating shaft and the rotating shaft to prevent seizure of the rotating shaft.
JP 2003-254275 A (page 3, FIG. 9)

  Therefore, the conventional vane-rotor type gas compressor cannot effectively suppress the strong vibration of the rotating shaft in the specific radial direction. In order to suppress the strong vibration in the specific radial direction of the rotating shaft described above, it is conceivable to adopt a circular hole whose diameter is smaller than the conventional appropriate value for the circular bearing hole. . However, in this case, since the distance from the bearing becomes smaller than the appropriate value over the entire circumference of the bearing hole, there is a possibility that the rotating shaft may be seized.

  Therefore, an object of the present invention is to provide a gas compressor that can effectively suppress vibration in a specific radial direction of a rotor without causing seizure of a rotating shaft.

  The invention described in claim 1 has a cylinder defining a cylinder chamber having an elliptical cross-sectional shape as a whole and provided with a pair of discharge holes and a pair of suction holes, and a rotating shaft having a circular cross-sectional shape. In order to define a plurality of pressure chambers in the cylinder chamber, an odd number of vanes are held to be pressed toward the peripheral wall of the cylinder chamber and rotated into the cylinder chamber to slide the vane on the peripheral wall. In a gas compressor comprising a rotor that can be accommodated and a bearing provided in the cylinder and provided with a bearing hole that receives the rotation shaft, vibration of the rotation shaft in a direction perpendicular to the axis of the rotation shaft The inner diameter of the bearing hole in a direction coinciding with the maximum amplitude direction in which the amplitude is maximum is set to be smaller than the inner diameter in a direction positioned at a right angle to the direction.

  According to a second aspect of the present invention, in the gas compressor according to the first aspect, the discharge holes are arranged to face each other in the radial direction in the vicinity of the short diameter portion of the cylinder chamber, and the rotating shaft is The bearing generates a vibration with a maximum amplitude in a radial direction having a deviation of a predetermined rotation angle toward a side of each discharge hole closer to each short diameter part than a short diameter direction connecting the both short diameter parts of the cylinder, The hole has an overall elliptical cross-sectional shape defined by a minor axis direction substantially coincident with the maximum amplitude direction and a major axis direction perpendicular to the minor axis direction.

  According to a third aspect of the present invention, in the gas compressor according to the second aspect, the minor axis direction of the bearing hole is from about 150 degrees to about the rotation direction of the rotor from the minor axis direction of the cylinder chamber. It is characterized by being within an angle range of up to 160 degrees.

  According to a fourth aspect of the present invention, in the gas compressor according to the third aspect, the odd number of vanes are held by the rotor at intervals in the circumferential direction of the rotor. .

  According to the first aspect of the present invention, the bearing hole has an inner diameter in a direction that coincides with the maximum amplitude direction of the rotating shaft that is received in the bearing hole, compared to an inner diameter in a direction that is perpendicular to the direction. Therefore, the maximum diameter of the bearing hole is set to substantially the same value as the inner diameter of the conventional circular bearing hole effective for preventing seizure, and the bearing hole in the direction matching the maximum amplitude direction of the rotating shaft is set. Can be set smaller than before. As a result, a gap effective for preventing seizure of the rotating shaft can be partially left in the circumferential direction of the bearing hole between the bearing hole and the rotating shaft received in the bearing hole. It is possible to effectively suppress vibrations in a specific radial direction of the rotor without causing occurrence.

According to the second aspect of the present invention, the bearing hole has an elliptical shape represented by, for example, an n-th power continuous ellipse, an n-th power discontinuous ellipse, or a general ellipse well known as X ² + Y ² = R ² . Thus, the maximum amplitude of vibration of the rotating shaft can be effectively reduced without causing seizure of the rotating shaft.

(Equation 1)
The nth power continuous ellipse is given by the following formula: R (θ) = r
(0 ° ≦ θ ≦ α °, 180−α ° ≦ θ ≦ 180 + α °, 360−α ° ≦ θ ≦ 360 °)

R (θ) = r + Lsin ⁿ {90 / (90−α) · (θ−α)}
(Α ° ≦ θ ≦ 180−α °, 180 + α ° ≦ θ ≦ 360−α °)
here
r: minor axis dimension n: multiplier α: minor axis angle range θ: 0 to 360 °
However, θ = 0 in the above formula is a position of 150 to 160 ° in the maximum amplitude direction.
It can be expressed by the general formula of

An n-th power discontinuity ellipse is expressed by the following equation: R (θ) = r ₁
(0 ° ≦ θ ≦ α °, 180−α ° ≦ θ ≦ 180 + α °, 360−α ° ≦ θ ≦ 360 °)

R (θ) = r ₂ + Lsin ⁿ θ
(Θ: Angle range other than the above)
here
r ₁ : Dimension of minor axis r ₂ : Radial dimension (r ₁ > r ₂ )
n: multiplier α: minor axis angle range However, θ = 0 in the above formula is a position of 150 to 160 ° in the maximum amplitude direction.
It can be expressed by the general formula of

  According to the third aspect of the present invention, the minor axis direction of the bearing hole is positioned within an angle range of about 150 degrees to about 160 degrees from the minor axis direction of the cylinder chamber toward the rotation direction of the rotor. As a result, the maximum amplitude of vibration of the rotating shaft can be effectively reduced without causing seizure of the rotating shaft.

  According to the invention described in claim 4, since the number of the vanes is an odd number, the pressure from the pressurizing chamber acting on the rotating shaft can be balanced with each other in the diameter direction of the rotating shaft. This is advantageous for reducing vibration of the rotating shaft.

  According to the present invention, as described above, a gap effective in preventing seizure can be partially left in the circumferential direction of the bearing hole between the bearing hole and the rotating shaft received in the bearing hole. Vibration in a specific radial direction of the rotor can be effectively suppressed without causing seizure on the rotating shaft.

  The features of the present invention will become more apparent from the following description along with the illustrated embodiments.

  In the example shown in FIG. 1, the gas compressor 10 according to the present invention is used for compressing a refrigerant in, for example, a vehicle air conditioning system, and although not shown, a conventionally well-known condenser, expansion valve, evaporator, etc. At the same time, a circulation path for the refrigerant is formed.

  The gas compressor 10 is a vane rotary compressor. The gas compressor 10 includes a housing 11 including a housing main body 11a formed of a cylindrical body having one end open and a front housing member 11b that closes the open end of the housing main body. The housing 11 accommodates a cylinder 12 having a cylindrical cylinder member 12a open at both ends, and a front side block 12b and a rear side block 12c that close each end of the cylindrical cylinder member. As shown, a cylinder chamber 13 having an elliptical cross section defined by the major axis direction X and the minor axis direction Y is formed.

  Referring to FIG. 1 again, the cylinder chamber 13 is provided with a rotor 17 having a rotating shaft 16 rotatably supported by sliding bearings 14 and 15 formed in both side blocks 12b and 12c. The rotating shaft 16 has the same circular cross-sectional shape as in the prior art. Further, as clearly shown in FIG. 2, the rotor 17 has a circular cross-sectional shape, and the rotor 17 is formed with vane grooves 18 including five slit grooves extending radially, and each vane is formed. In the groove 18, there is a vane 20 that receives a biasing force toward the peripheral wall of the cylinder chamber 13 due to a centrifugal force acting when the rotor 17 rotates and a hydraulic pressure guided to the back pressure chamber 19 formed at the bottom of the vane groove 18. Contained. Each vane 20 divides the cylinder chamber 13 into a plurality of pressurizing chambers 13a in the circumferential direction, and slides while maintaining airtightness with the wall surface of the cylinder chamber 13 as the rotor 17 rotates. It is held in the vane groove 18.

  In the cylinder member 12a, a pair of discharge holes 21 are formed in the cylinder chamber 13 so as to open at the peripheral wall. The pair of discharge holes 21 are arranged symmetrically with respect to the rotating shaft 16 in the vicinity of the minor axis direction Y of the cylinder chamber 13 as in the prior art, and each discharge hole 21 is a short adjacent to each of the cylinder members 12a. It is arranged on the side opposite to the rotation direction of the rotor 17 as viewed from the diameter portion, that is, on the counterclockwise direction side in the example shown in FIG. Each discharge hole 21 is provided with a well-known check valve 22 that allows discharge of compressed gas from the pressurization chamber 13a through the discharge hole 21.

  Further, as shown in FIG. 3, a pair of suction holes 23 are formed in the front housing member 11b. The two suction holes 23 are arranged with respect to each other with respect to the rotary shaft 16, and each of them opens to the cylinder chamber 13 through the front side block 12 b at its side wall.

  As shown in FIG. 1, a cylindrical shaft portion 24 is formed in the front housing member 11b, and the shaft portion rotates at the front end portion of the rotary shaft 16 passing through the sliding bearing 14 of the front side block 12b. Accept as possible. Between the shaft portion 24 and the rotary shaft 16, an annular seal mechanism 24 a for preventing the lubricant oil from flowing out along the rotary shaft 16 is provided. The shaft portion 24 is rotatably provided with a pulley 26 via a rolling bearing 25 composed of an annular ball bearing disposed around the outer periphery thereof. In the illustrated example, an electromagnet device 27 is incorporated in the pulley 26.

  As is well known in the art, the electromagnet device 27 is a clutch that is supported by an armature 28 fixed to the distal end portion of the shaft portion 24 via a leaf spring 29 that is an elastic body and that is spaced from the side portion of the pulley 26. By combining the pulley 26 and the armature 28 by overcoming the spring force of the plate spring 29 and adsorbing the plate 30 with an electromagnetic adsorption force, the two can be rotated together. The clutch plate 30, the electromagnet device 27, and the like constitute a so-called electromagnetic clutch mechanism.

  A pulley (not shown) is hung on the pulley 26, and the pulley 26 is rotated by transmitting a rotational force from a driving source such as an engine mounted on an automobile through the belt. When the electromagnet device 27 of the electromagnetic clutch mechanism is de-energized, the clutch plate 30 is held at a distance from the side surface of the pulley 26 by the spring force of the plate spring 29, so that the rotary shaft 16 rotates. Thus, therefore, the gas compressor 10 is put into a non-operating state.

  When electric power is supplied to the electromagnet device 27 by energization of the electromagnet device 27, the clutch plate 30 rotates integrally with the pulley 26 by the electromagnetic attraction force, so that the rotational force is applied to the rotating shaft 16 via the armature 28. Then, the rotor 17 rotates clockwise as viewed in FIG. Each vane 20 slides on the peripheral surface of the cylinder chamber 13 by the rotation of the rotor 17, and along with this sliding, suction, compression, and discharge in each pressurizing chamber 13a are well known. Each process proceeds.

  In the suction stroke, as shown in FIG. 1, a low-temperature and low-pressure refrigerant discharged from the evaporator (not shown) from a suction port 31 provided in the front housing member 11b through a check valve 32 provided in the suction port. Gas is sucked into the pressurizing chamber 13a from the suction hole 23 (see FIG. 3). The refrigerant gas sucked into the chamber 13a is compressed in the compression stroke and becomes a high-temperature and high-pressure refrigerant gas. This high-temperature and high-pressure refrigerant gas passes through the discharge hole 21 (see FIG. 2) from the pressurizing chamber 13a in the discharge process, and enters the high-pressure chamber 33 and the housing body 11a provided in the housing 11 as shown in FIG. It is sent to the condenser (not shown) through the provided outlet 34.

  In the high-pressure chamber 33, as shown in FIG. 1, a well-known oil separator 35 for separating lubricating oil contained in the refrigerant from the refrigerant is provided, and the oil separator is separated from the compressed refrigerant. Lubricating oil 36 separated by 35 is stored at the bottom of the high pressure chamber 33. The lubricating oil 36 in the high pressure chamber 33 passes through oil passages 37, 38, and 39 provided in the rear side block 12c, the cylindrical cylinder member 12a, and the front side block 12b, respectively, due to the pressure in the high pressure chamber 33. Supplied to the sliding bearings 14 and 15. Further, a part of the lubricating oil 36 supplied toward the slide bearings 14 and 15 is stored in the vane grooves 18 for receiving the vanes 20 in the oil sump recesses provided in the front side blocks 12b and the rear side blocks 12c. After 40 (Saray), it is guided to the back pressure chamber 19.

  As described above, each vane 20 appropriately slides on the peripheral wall of the cylinder chamber 13 along with the rotation of the rotor 17 as described above due to the biasing force including the hydraulic pressure and centrifugal force in the back pressure chamber 19. Each process of suction, compression and discharge proceeds.

  Due to the rotation of the rotor 17, the rotation shaft 16 that rotates integrally with the rotor generates vibrations with various radial amplitudes on a plane perpendicular to the axis of the rotation shaft. Among these vibration directions, as indicated by a symbol M in FIG. 2, the amplitude along a specific radial direction M in the vicinity of the minor axis direction Y of the cylinder chamber 13 is maximized. This maximum amplitude direction M is in the vicinity of the short diameter portion of the cylinder member 12a, on the side of the one discharge hole 21 close to the short diameter portion, from the short diameter direction Y to the direction opposite to the rotation direction of the rotor 17 by an angle θ. Matches the biased direction.

  This is considered to be due to the fact that the pressurization state in the pressurization chamber 13a is released at once when the pressurization chamber 13a in which pressurization proceeds with the rotation of the rotor 17 reaches the discharge hole 21, FIG. As shown in FIG. 4, the maximum amplitude direction M exists within an angle range of 150 degrees to 160 degrees from the minor axis Y to the rotation direction of the rotor 17.

  In the example shown in FIG. 2, the maximum amplitude direction M exists in the middle of the angle range of 150 degrees to 160 degrees.

  In the gas compressor 10, the bearing holes 14 a and 15 a of the sliding bearings 14 and 15 are both formed in an elliptical shape so as to effectively suppress the vibration in the maximum amplitude direction M of the rotating shaft 16. .

  3 showing the relationship between one bearing hole 14a provided in the front side block 12b and the rotating shaft 16 received in the bearing hole, and FIG. 4 showing the bearing hole 14a in an enlarged manner. The bearing hole 14a of the slide bearing 14 has a minor axis L1 in a direction that coincides with the maximum amplitude direction M described above, that is, a direction that is offset by an angle θ from the minor axis direction Y of the cylinder chamber 13 in the direction opposite to the rotational direction of the rotor 17. Have. Further, a major axis L2 is provided in a direction N perpendicular to the minor axis L1, that is, a direction N coinciding with a direction perpendicular to the maximum amplitude direction M. The bearing hole 14a has an elliptical shape defined by an ellipse having the minor axis L1 and the major axis L2. The short diameter L1 described above is the inner diameter L1 of the bearing hole 14a in a direction coinciding with the maximum amplitude direction M of the vibration of the rotary shaft 16, and the long diameter L2 is the direction of the bearing hole 14a in a direction perpendicular to the inner diameter L1. The inner diameter is L2.

  A conventional bearing hole for receiving a rotary shaft having a circular cross-sectional shape without seizure is indicated by reference numeral 14 'in FIG. On the other hand, the bearing 14 having an elliptical shape according to the present invention has a major axis L2 equal to the diameter of the conventional circular bearing hole, but the minor axis L1 corresponding to the maximum amplitude direction of the rotary shaft 16 is A value smaller than the diameter of the conventional bearing hole 14 ', that is, the major axis L2.

  Therefore, the sliding bearing 14 maintains a gap sufficient to prevent the rotary shaft 16 from being seized at and near the major axis L2 of the bearing hole 14a, and on the other hand, in the maximum amplitude direction M of the rotary shaft 16. The vibration in the maximum amplitude direction of the rotating shaft 16 is effectively suppressed in the vicinity of the corresponding minor axis L1 and in the vicinity thereof.

  The other slide bearing 15 provided in the rear side block 12c is not shown, but the direction corresponding to the maximum amplitude direction M is the same as that shown in FIGS. 3 and 4, and the direction is perpendicular to this direction. The bearing hole 15a (refer FIG. 1) of the elliptical shape which makes the direction N to do as a long diameter is provided. Accordingly, the sliding bearing 15 retains a gap sufficient to prevent the rotary shaft 16 from being seized at the long diameter portion and the vicinity thereof, as in the sliding bearing 14, while the maximum amplitude of the rotary shaft 16 is maintained. The vibration of the rotation axis 16 in the maximum amplitude direction M is effectively suppressed in the vicinity of the minor axis that coincides with the direction M and in the vicinity thereof.

  As a result, according to the gas compressor 10 according to the present invention, it is possible to reliably prevent the rotating shaft 16 from being seized by the rotation of the rotating shaft 16 and to the specific direction (M) of the rotating shaft 16. Strong vibration can be effectively suppressed, and noise caused by this vibration can be reduced.

  The shapes of the bearing holes 14a and 15b of the plain bearings 14 and 15 can be expressed by an elliptical general formula as shown by the following formula (1).

X ² + Y ² = R ² (1)
Instead of this, the shape of each of the bearing holes 14a and 15b can be an n-th power continuous ellipse or an n-th power discontinuous ellipse as represented by the following equations.

(Equation 2)
The n-th power continuous ellipse is expressed by equations (2) and (3).

R (θ) = r (2)
(0 ° ≦ θ ≦ α °, 180−α ° ≦ θ ≦ 180 + α °, 360−α ° ≦ θ ≦ 360 °)

R (θ) = r + Lsin ⁿ {90 / (90−α) · (θ−α)} (3)
(Α ° ≦ θ ≦ 180−α °, 180 + α ° ≦ θ ≦ 360−α °)
here
r: minor axis dimension n: multiplier α: minor axis angle range θ: 0 to 360 °
It can be expressed by the general formula of

In addition, the nth power discontinuity ellipse is expressed by Equations (4) and (5).

R (θ) = r ₁ (4)
(0 ° ≦ θ ≦ α °, 180−α ° ≦ θ ≦ 180 + α °, 360−α ° ≦ θ ≦ 360 °)

R (θ) = r ₂ + Lsin ⁿ θ (5)
(Θ: Angle range other than the above)
here
r ₁ : Dimension of minor axis r ₂ : Radial dimension (r ₁ > r ₂ )
n: Multiplier α: Can be expressed by a general formula of the minor axis angle range.

  However, in Equation (2), Equation (3), Equation (4), and Equation (5), θ = 0 matches the position of 150 to 160 ° in the maximum amplitude direction.

  In the above description, the present invention has been described along the example in which the minor axis direction of each of the bearing holes 14a and 15b is matched with the maximum amplitude direction M. However, the minor axis direction of each of the bearing holes 14a and 15b has the maximum amplitude. It can be set with a slight deviation from the maximum amplitude direction M in the above-mentioned angular range of 150 to 160 degrees so as to substantially coincide with the direction M. Further, a rolling bearing can be used instead of the sliding bearing.

It is a longitudinal section showing a gas compressor concerning the present invention. It is sectional drawing obtained along the II-II line | wire shown in FIG. It is sectional drawing obtained along the III-III line | wire shown in FIG. It is explanatory drawing which expands and shows the bearing hole shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Gas compressor 11 Housing 12 Cylinder 13 Cylinder chamber 13a Pressurization chamber 14, 15 (Bearing) Sliding bearing 14a, 15a Bearing hole 16 Rotating shaft 17 Rotor 20 Vane 21 Discharge hole 23 Suction hole

Claims (4)

  A cylinder defining a cylinder chamber having an elliptical cross-sectional shape as a whole and provided with a pair of discharge holes and a pair of suction holes, and a rotary shaft having a circular cross-sectional shape. A rotor that rotatably holds each of the plurality of vanes toward the peripheral wall of the cylinder chamber to define a pressure chamber, and is rotatably accommodated in the cylinder chamber to slide the vane on the peripheral wall; A bearing provided in the cylinder and provided with a bearing hole for receiving the rotating shaft, and the amplitude of vibration of the rotating shaft in a direction perpendicular to the axis of the rotating shaft coincides with the maximum amplitude direction indicating the maximum value. The gas compressor according to claim 1, wherein an inner diameter of the bearing hole in a direction is set to be smaller than an inner diameter in a direction positioned at right angles to the direction.   The discharge holes are disposed in the vicinity of the short diameter portion of the cylinder chamber so as to be opposed to each other in the radial direction, and the rotation shaft has each short diameter portion connected to the short diameter portion connecting the short diameter portions of the cylinder. A vibration having a maximum amplitude in a radial direction having a predetermined rotation angle bias toward the side of each of the discharge holes, wherein the bearing hole has a minor axis direction substantially coincident with the maximum amplitude direction, and the minor axis direction The gas compressor according to claim 1, wherein the gas compressor has an overall elliptical cross-sectional shape defined by a major axis direction perpendicular to the axis.   The minor axis direction of the bearing hole is within an angle range from about 150 degrees to about 160 degrees from the minor axis direction of the cylinder chamber toward the rotation direction of the rotor. Gas compressor.   The gas compressor according to claim 3, wherein the odd number of vanes are held by the rotor at intervals in the circumferential direction of the rotor.

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