JPH01100397A - Gas compressor - Google Patents

Abstract

PURPOSE:To reduce frictional torque before compression is started, by furnishing a communicating means for communication with the compression side formed in a cylinder chamber at the bottom side of a recess in which a plurality of vanes are fitted, formed at a rotor accommodated in the cylinder chamber with approx. elliptical profile. CONSTITUTION:Cylinder chamber (a) of a gas compressor is bounded by an approx. cylindrically formed cylinder block 4 and side blocks arranged on its both sides, and in this chamber (a) at its periphery, a cylindrical rotor 9 fitted with flat plate shaped vanes 8 with possibility of advancing and retracting in the radial direction is accommodated rotatably. Each vane 8 is fitted slidably in a groove-shaped recess 9a formed at the rotor 9 radially. A communicating means in the form of longitudinal grooves 8a starting a little below the tip and reaching the tail is formed at the surface on the compression side of vane 8, and the compression side of cylinder chamber (a) formed before the vane 8 viewed in its rotational direction is put in communication with a small chamber 9b of the rotor 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a gas compressor, and particularly to a rotary vane type gas compressor used in Kartara and other relatively small-sized refrigeration equipment.

(Summary of the Invention) In the present invention, since the vane pressure of the gas compressor is generated using the pressure on the compression side of the cylinder chamber, the friction torque before compression starts can be suppressed to a low level.

(Prior Art) Fig. 7.8 shows a conventional variable capacity compressor.

That is, this gas compressor includes a compressor main body 1, a casing 2 with an open end that airtightly surrounds the main body, and a front head 3 attached to the open end surface of the casing 2.

The gas compressor 1 includes a cylinder block 4 having a substantially elliptical inner circumference, and a front side block 5 and a rear side block 6 attached to both sides of the cylinder block 4.
In the cylinder chamber a, which has a substantially elliptical inner circumference formed by the side block, there are five flat plates that are integral with the rotor shaft 7 and can freely move forward and backward in the radial direction of the rotor shaft 7. A solid cylindrical rotor 9 equipped with shaped vanes 8 is horizontally suspended so as to be freely rotatable.

The vane 8 is attached to the rotor 9 by forming a groove around the rotor 9 that extends in the direction of its rotation axis, has a cross section slightly larger than the cross section of the vane 8, and has a depth slightly larger than the height of the vane 8. A groove-shaped recess 9a is provided, and the vane 8 is inserted into this groove-shaped recess 9a.

Further, a small chamber 9b having a larger cross-sectional area than the upper portion is formed at the bottom of the groove-shaped recess 9a.
The lubricating oil O inside the casing 2 is supplied to b. That is, the lubricating oil O is in the cylinder block 4.
．． The oil is supplied to the bearing portion of the rotor shaft 7 through the oil distribution channels 4a, 5a, and 6a formed in the front side block 5 and the rear side block 6, and after lubricating the bearing portion of the rotor shaft 7, the oil is supplied to the rear side block 6 and the control plate 1, which will be described later.
0 through the grooves 21 and 22 formed at
b.

Roughly, between the front side block 5 and the cylinder block 4, control plates 1 to 10 in the shape of a circular disk are fitted and supported on the rotor shaft 7, and the control plate 10 is rotated at a predetermined angle. It is movably driven, and bypass recesses 11.11 are formed in its peripheral edge so as to be 180° opposed to each other. It communicates with a bypass hole provided in the.

That is, this control plate 10 is rotatable within a predetermined angle, and for example, during low-speed operation, the control plate 10 is placed in a position that does not bypass the intake refrigerant gas, ensuring the maximum capacity of the compression work chamber. .

On the other hand, during high-speed operation, the control plate 10 rotates in the clockwise direction in FIG. The gas is bypassed to the suction chamber side through the bypass hole, and as a result, the capacity of the compression chamber is reduced, and the gas is compressed by only the reduced capacity.

To explain the flow of refrigerant gas in the variable capacity gas compressor configured in this way, first, the refrigerant gas introduced into the suction chamber 15 from the intake hole 14 provided in the front head 3 flows as shown by the solid line in FIG. As shown by arrow A, the communication hole 12
It is introduced into an intake passage 16 formed through the cylinder block 4, and notches 17 are formed at both ends of this intake passage 16.
a, 17b are provided, and high pressure gas is sucked into the cylinder chamber a from these notches 17a, 17b, and then compressed by the rotation of the vane 8, to a discharge port 18a.

The oil is supplied to the oil separator 19 provided at the back of the rear side block 6 through the discharge valve 18b and through a communication hole (not shown) provided in the rear side block 6, and is then supplied to the casing 2 as shown by the broken line arrow in FIG. Outlet 20 from the rear space of
It is then discharged to the outside.

Furthermore, since the lubricating oil 0 in the casing 2 is maintained at a high pressure with compressed high-pressure gas, the cylinder block 4. Oil flow path 4a formed in front side block 5 and rear side block 6.

The pressure of the lubricating oil O in the small chamber 9b supplied via 5a and 6a also increases, and vane pressure is generated. That is, the tip of the vane 8 applies a pressing force to the inner wall of the cylinder chamber a, thereby preventing chattering during compression work.

(Problem to be Solved by the Invention) However, in the above gas compressor, the vane pressure is always maintained high due to pressurized lubricating oil pressure, so the friction torque at the vane tip is large and the driving power is large. There were drawbacks.

Particularly during high-speed operation of a variable capacity compressor, there is a problem in that the vane pressure is maintained high even during non-compression until the vane tip passes through the bypass hole, resulting in an increase in friction torque.

Further, as the frictional torque increases, the amount of frictional heat increases, which not only increases the temperature of the discharged gas, but also causes problems such as severe wear of the vanes.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and consists of a cylinder block having side blocks on both sides and a substantially elliptical cylindrical inner circumference; A rotary vane type gas compressor comprising a cylinder block and a rotor having a plurality of vanes that are rotatable in a cylinder chamber formed by both side blocks and that can move forward and backward in groove-like recesses provided in the radial direction. It is characterized in that a communication means is provided on the bottom side of the groove-like recess to communicate with the compression side formed in the cylinder chamber in front of the vane in the rotational direction.

(Function) - With the above configuration, the present invention generates vane pressure at the pressure on the compression side of the cylinder chamber, so the vane pressure is low before compression starts, and increases when compression starts. It works like this.

(Description of an embodiment) Hereinafter, an embodiment of a gas compressor according to the present invention will be described using the accompanying drawings.

In this embodiment, the same reference numerals are used for the same components as in the prior art, and since the explanations for these components will overlap, only new parts will be explained using different reference numerals.

1 to 4 show a first embodiment of a gas compressor according to the present invention, in which FIG. 1 is a longitudinal sectional view thereof, and FIG. 2 is a sectional view taken along line A-A in FIG. , FIG. 3 is a perspective view of the vane, and FIG. 4 is an explanatory diagram showing the relationship between the contact angle of the vane and the friction torque.

In the figure, 8a denotes a plurality of grooves (three in this example) cut in the compression side of the vane 8 starting slightly below the tip and reaching the rear end in the cylinder chamber a. The compression side formed at the front of the vane 8 in the rotational direction and the small chamber 9b of the rotor 9 communicate with each other.

Therefore, the rotation of the rotor 9 causes the vane 8 to move into the cylinder chamber a.
When rotating inside, the pressure on the compression side is not high at the beginning of rotation, so the pressure in the small chamber 9b is also low, the vane pressure is not high, and the friction torque is small. However, as the rotation of vane 8 progresses,
When the compression side pressure increases, the pressure is transmitted to the small chamber 9b via the groove 8a, so that a force that pushes the vane 8 toward the cylinder chamber a side, that is, a vane pressure is generated. This results in
A vane pressure sufficient to withstand compression work is obtained, and chattering phenomenon is prevented. In other words, the vane pressure is low before compression starts and becomes high after compression starts.

By the way, during low-speed operation, the control plate 10 does not bypass the refrigerant gas, so the compression side in the cylinder chamber a,
That is, the capacity of the compression work chamber becomes large, and compression starts when the vane contact angle (rotation angle) is around 54°, as shown in FIG.

Therefore, the vane pressure increases from this vicinity, and the friction torque increases accordingly (see the solid line in FIG. 4).

On the other hand, during high-speed operation, the control plate 10 is rotated by a predetermined angle according to the speed by a control plate drive means (not shown), and the refrigerant gas is bypassed, thereby reducing the capacity of the compression work chamber. Therefore, the angle at which the vane 8 starts compressing becomes slower (approximately 180'), and the rise in vane pressure also becomes slower (see the dotted chain line in FIG. 4).

As described above, in this embodiment, the pressure on the compression side in the cylinder chamber a and the pressure in the small chamber 9b in the rotor 9 become the same due to the communication means of the groove 88 cut in the vane 8, and this pressure causes the vane to Since pressure is generated, the vane pressure is only due to centrifugal force before compression starts, and the friction torque becomes substantially equal to O. This is significantly less than the conventional pressurized lubricating oil, which generates friction torque from the start of vane rotation as shown by the chain line in Figure 4, and vane wear is significantly reduced. Furthermore, since the amount of heat generated is also reduced, the temperature of the discharged gas can also be kept low.

Further, unlike the conventional method, there is no need to provide a groove or the like for supplying pressurized lubricating oil to the small ib in the rotor 9, so the structure is simplified.

FIG. 5 shows a second embodiment of the present invention,
The communication means is constructed by providing a groove 9C in the wall surface of the groove-shaped recess 9a of the rotor 9 on the rotation direction side.

In this embodiment, the compression side of the cylinder ia and the small i9b in the rotor 9 communicate with each other through the groove 9c and have the same pressure, so that the same effect as in the first embodiment described above can be obtained.

Furthermore, FIG. 6 shows a third embodiment of the present invention, in which a through hole 9d is provided near the rotational direction side of the groove-shaped recess 9a of the rotor 9, communicating between the outer periphery of the rotor 9 and the small chamber 9b. It constitutes a communication means. Note that the opening position of the through hole 9d to the outer periphery of the rotor 9 is set close to the groove-shaped recess 9a side so that when the vane 8 is located on the discharge boat 18a, it is not yet located in the rear cylinder chamber a. ing.

In the above embodiments as well, the compression side of the cylinder chamber a and the small chamber 9b in the rotor 9 communicate with each other through the through hole 9d and have the same pressure, so it is possible to obtain the same effects as in each of the embodiments described above. can.

In each of the embodiments described above, the cross-sectional area of the small chamber 9b provided in the rotor 9 is larger than that of the groove-shaped recess 9a, but they may have the same cross-sectional area.

(Effects) As described above, in the gas compressor according to the present invention,
Since the vane pressure is obtained from the pressure in the cylinder chamber, the friction torque can be substantially reduced to O until compression starts, so driving power can be saved and the amount of frictional heat can be reduced.

Further, since the frictional torque is reduced, the wear of the vanes is also reduced, and since the amount of frictional heat is small, the temperature of the discharged gas can also be lowered.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of a gas compressor according to the present invention, in which FIG. 1 is a longitudinal sectional view thereof, FIG. 2 is a sectional view taken along line A-A in FIG. Figure 3 is a perspective view of the vane, Figure 4 is a perspective view of the vane.
The figure is an explanatory diagram showing the relationship between vane contact angle and friction torque.
Fig. 5 is a cross-sectional view showing a second embodiment of the present invention, Fig. 6 is a cross-sectional view showing a third embodiment of the present invention, and Figs. 7 and 8 show a conventional gas compressor. 7 is a longitudinal sectional view thereof, and FIG. 8 is a sectional view taken along the line B--B in FIG. 7. 1... Gas compressor main body 2... Casing 3... Front head 4... Cylinder block 5... Front side block 6... Rear side block 7... Rotor shaft 8... Vane 8a ...Groove (communicating means) 9...Rotor 9a...Groove-shaped recess 9b...Small chamber 9C...Groove (communicating means) 9d...Through hole (communicating means) 10...Control plate 11... Bypass recess 12... Communication hole 14... Intake hole 15... Intake to 16... Intake passage 17a, 17b... Notch 18a... Discharge port 18b... Discharge Valve 19...Oil separator 20...Discharge port 21.22...Groove a...Cylinder chamber Patent applicant Seiko Seiki Co., Ltd. Agent Patent attorney Kazu 1) Seiji Figure 2 Figure 1 A -A-line sectional view Figure 3 Vane perspective view Figure 4 Relationship between vane contact angle and friction torque Vane contact angle -

Claims (1)

[Claims] (1) A cylinder block with side blocks on both sides and a substantially oval cylindrical inner circumference, and a groove-shaped recess rotatably provided in the cylinder chamber formed by the cylinder block and both side blocks in the radial direction. In a rotary vane type gas compressor comprising a rotor having a plurality of vanes that can move forward and backward, a communication means is provided on the bottom side of the groove-like recess to communicate with a compression side formed in a cylinder chamber in front of the vane in the direction of rotation. A gas compressor characterized by: