JPS6161994A - Through vane type compressor - Google Patents

Abstract

PURPOSE:To reduce the sliding resistance with simple processing by providing the casing at its inside surface with an enlarged diameter part so that the tip surface of each vane is free from slide contact, wherein said enlarged part is situated between the discharge port and suction port oriented in the rotational direction of rotor. CONSTITUTION:A casing 8 is provided at its inside surface with an enlarged diameter part 30, which shall be a little greater than the original inside surface 8b of the casing 8 and be situated between the discharge port 15 and suction port 14 as oriented in the rotational direction of the rotor 1. This allows the tip of each vane 7a, 7b to be free from slide contact with the casing. The circumferential length of this enlarged diameter part 30 shall range between theta=10 deg. and 90 deg. with theta=0 deg. used as reference point. No sealing is required in this zone around theta=10 deg.-90 deg., as it serves for the expansion stroke, and therefore the vane tips being off contact with the inside surface of the casing in this part will not present any substantial problem.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a through-vane compressor in which vanes provided on an eccentric rotor are integrally formed diagonally and slide against the inner surface of a casing.

(Technical Background of the Invention) As is widely known from Japanese Patent Application Laid-Open No. 58-38395, a vane type compressor has vanes that are provided on an eccentric rotor so as to be freely projectable and retractable in the radial direction. The rotor is in sliding contact with the inner surface of the casing to compress fluid, such as oil or refrigerant, in the pump chamber formed between the inner surface of the casing, the rotor, and adjacent vanes.

By the way, a vane type compressor in which diagonal vanes are integrally connected is called a through-vane type compressor, and a conventional through-vane type compressor will be explained with reference to FIGS. 2 and 3. In the figure, reference numeral 1 denotes an eccentric rotor that also serves as a drive shaft, and both ends thereof are rotatably supported via bearings 4 and 5 at eccentric positions with respect to front and rear side plates 2 and 3. A plurality of sliding grooves 6 are formed in the rotor 1 in the radial direction.
... have vanes 7a and 711 fitted in them so as to be slidable in the radial direction, respectively. The vanes 7a, 71) are integrally formed diagonally, so that the overall length is always kept constant.

8 is a casing, and the side plates 2 and 3 are
The rotor 1 and the vane 7a are sandwiched between the rotor 1 and the vane 7a.

71) and the pump chamber V as a compression space surrounded by side plates 2 and 3! ~ Configure V4.

9 is a front housing, which forms a suction pressure space 10 between the front side plates 2;

11 is a rear housing, and a rear side plate 3
A discharge pressure space 12 is formed between the two. These Freon 1~
Housing 9, rear housing 11, casing 8. The side plates 2 and 3 are fixed by poles 1 to 13...

A suction port 14 is provided in the front side plate 2, and discharge ports 1 to 15 are provided in the casing 8 at positions spaced apart from the suction port 14 in the circumferential direction. The discharge boat 15 is provided with a discharge valve 16. The discharge valve 16 is covered by a cover 17, and the space inside the cover 17 communicates with the discharge pressure space 12. 18 is a valve stopper, and 19 is a mechanical seal. In a through-vane compressor with such a configuration, when the rotor 1 is rotated clockwise in FIG. 3, the vanes 7a and 7b are also integrally rotated in the same direction. be rotated. Therefore, the vanes 7a, 7b are pressed against the inner surface 8a of the casing 8 by centrifugal force, and come into sliding contact with the inner surface 8a of the casing 8. Therefore, the volumes of the pump chambers V1 to V4 change as the rotor 1 rotates, and perform suction and discharge operations.

In this type of through-vane compressor, the vanes 7a and 7b having a constant length L rotate, so the liquid tightness of the pump chamber is greatly influenced by the shape of the inner surface 8a of the casing 8. That is, in the vane 7a in the state shown in FIG. 3, centrifugal force is generated in the six directions of the arrows, so that one end 7aa of the vane 7a tends to be pressed against the inner surface 8a of the casing 8. At this time, the other end 7ab of the vane 7a tries to move away from the inner surface 8a of the casing 8, but since the region where the other end 7ah of the vane 7a is located is in the discharge stroke, high sealing performance is required.
Therefore, this portion of the inner surface 8a of the casing 8 requires highly accurate machining.

[Problems with background technology]

As mentioned above, in this type of through-vane compressor, the inner surface 8a of the casing 8 has a shape that extends over the entire circumference based on the viewpoint that the liquid tightness of the pump chamber is greatly influenced by the shape of the inner surface 8a of the casing 8. High precision surface processing was applied. However, performing high-precision surface processing over the entire circumference requires time and effort, and there is a problem that productivity decreases.

That is, considering the other vane 71) in the state shown in FIG. 3, centrifugal force is generated in this vane 7b in the direction of arrow B, so one end 7ab of the vane 7b tends to be pressed against the inner surface 8a of the casing 8. At this time vane 7b
The other end 7bb tends to separate from the inner surface 8a of the casing 8. Since the region where the other end 7bb of the vane 7b is located is in the suction stroke, the fluid pressure is low and high precision sealing is not required. Therefore, the machining accuracy of this part should be reduced.

[Purpose of the invention]

The present invention was made based on the recognition of the above-mentioned circumstances, and its purpose is to provide a through-vane compressor that improves productivity by reducing the shape accuracy of the inner surface of the casing in low-pressure regions where high sealing performance is not required. That is.

[Summary of the invention]

To achieve the above object, the present invention forms a bulging diameter portion on the inner surface of the casing, which is located between the discharge boat and the suction port in the rotational direction of the rotor, so that the tip surface of the vane does not come into contact with the suction port, This bulging diameter portion is characterized in that no special surface processing is required because the tip surface of the vane does not come into sliding contact.

[Embodiments of the invention]

The present invention will be explained below based on an embodiment shown in FIG.

The present embodiment may be similar in most parts to the configuration of FIGS. 2 and 3 described above, so the same parts will be given the same numbers and the explanation thereof will be omitted. FIG. 1 is a view corresponding to the above-mentioned FIG. 3, and in the figure, reference numeral 30 indicates a bulged diameter portion according to the present invention formed on the inner surface of the casing 8. As shown in FIG. This bulging diameter portion 30
has a diameter several mm larger than the inner surface of the conventional casing 8 (indicated by phantom line 8b), and in the circumferential direction from the discharge port 15 to the suction port 14 along the rotational direction of the rotor 1. is formed between. Therefore, the vane 7a
, 7b, each tip surface 7aa, 7ab, 7ba
, 7bb C. It is designed not to come into sliding contact with the bulged diameter 130. Note that the length in the circumferential direction of the bulged diameter portion 30 in this embodiment is Θ=10 with Θ=〇° shown in FIG.
It is formed in the range of Θ=90'. The above o-0
The reference line of ° is a line connecting the rotation center of the rotor and the inner surface of the casing 8 closest to this rotation center, in other words, it is the position where the rotor 1 directly slides into the casing 8, and this type of through-vane compressor This position is generally used as a design reference line.

The operation of an embodiment of such a configuration will be explained.

Approximately ±10° (indicated by α) centered on the above reference line Θ=0° is the boundary between the high pressure side and the low pressure side, where the outer circumferential surface of the rotor 1 and the inner circumferential surface of the casing 8 are in surface contact, causing high pressure. It forms a seal between the side and the low pressure side. Then, since the tip of the vanes 7a and 7b is Θ=100, the vane (
While the vane (which together with the vane constitutes the pump chamber) passes through the suction port 14, it is in the suction stroke. Further, when such a suction stroke is completed, the engine moves to a compression stroke, and further moves to a stroke (discharge stroke) in which the compressed fluid is discharged from the discharge port 15 as the engine rotates.

In the state shown in FIG. 1, one end 7aa of the vane 7a is θ=9
It is located in a region (Z2) from 0° to θ=18°, and one end 7aa is pressed against the inner surface 8a of the casing 8 by centrifugal force. The other end 7ab of this vane 7a is 0
This is in the region (Z4) from =270° to e=350', and since this region is the discharge stroke, high sealing performance is required. Moreover, in the other vane 7b, one end 7b
Region where a is around Θ=1800 to Θ=270° (Z3)
This end 7ba is attached to the casing 8 due to centrifugal force.
is pressed against the inner surface 8a of. Since this region is a compression stroke, high sealing performance is required. That is, Θ=
In the range from 90° to Θ = 370° (Θ = 10°), the vanes 7a and 7b make sliding contact with the inner surface 8a of the casing 8, so in order to reduce wear and sliding noise and maintain sealing performance, surface accuracy is required. is highly demanded.

On the other hand, the other end 7bb of the other vane 7b has θ=
Located in the region from 10° to Θ = 90', casing 8
Trying to get away from the inner world of a. Therefore, even if the bulging diameter portion 30 is formed at this position, the tips of the vanes 7a and 7b do not come into sliding contact with the bulging diameter portion 30. From the above θ=10°, e=
Since the region around 90' is in the expansion stroke, sealing is not required, and there is no problem even if the tips of the vanes 7a, 7b do not come into sliding contact with the bulging diameter portion 30.

-9= Rather, this part requires fluid to be introduced from the suction port 14 side as the pump chamber ■1 is about to expand, and the vane 7
Fluid can be introduced into the pump chamber (1) through the gaps between the tips of the tubes (a) and (7b) and the inner surface of the bulging diameter portion (30).

Since the vanes 7a and 7b do not come into sliding contact with the bulging diameter portion 30, the sliding resistance is reduced, resulting in less power loss, and the machining accuracy of the bulging diameter portion 30 can be reduced, resulting in less machining effort. It becomes possible to improve productivity.

〔Effect of the invention〕

As described above, according to the present invention, a bulging diameter portion is formed on the inner surface of the casing between the discharge port and the suction port in the rotational direction of the rotor, with which the tip surface of the vane does not come into sliding contact. Therefore, there is no need for particularly sophisticated surface processing on this bulging diameter portion, and the processing accuracy of this portion can be reduced, resulting in improved productivity. Furthermore, since the tip surface of the vane does not come into sliding contact with the bulging diameter portion, sliding resistance is reduced and power loss is also reduced.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the present invention, Figs. 2 and 3 show a conventional structure, Fig. 2 is a sectional view, and Fig. 3 is a sectional view taken along line 111-1 in Fig. It is a diagram. 1... Rotor, 7a, 7ba... Vane, 8...
- Casing, 14... Suction port, 15... Discharge port, 30... Expanded diameter portion. Applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (2)

[Claims] (1) A casing having a cylindrical inner surface, a rotor provided eccentrically within the casing, and a rotor that is slidably attached to the rotor in the radial direction and is in sliding contact with the inner surface of the casing, thereby connecting the casing and the rotor. a plurality of vanes integrated diagonally to form a pump chamber whose volume is changed between the pump chambers, a suction port that sucks fluid into the pump chamber, and a pump chamber that is compressed when the volume is reduced In a through-vane compressor equipped with a discharge port for discharging fluid, the tip surface of the vane is in non-sliding contact with the inner surface of the casing located between the discharge port and the suction port in the rotational direction of the rotor. A through-vane compressor characterized by forming a bulging diameter portion. (2) The bulging diameter portion is defined by the line connecting the rotation center of the rotor and the inner surface of the casing closest to this rotation center at Θ=0°.
Θ toward the direction of the suction port.
2. The through-vane compressor according to claim 1, wherein the through-vane compressor is formed over a range of Θ = 10° to Θ = 90°.