JPH041493A - Hydraulic compressor - Google Patents

Abstract

PURPOSE:To balance each thrust force without increasing the number of part items as well as to reduce a friction loss attributable to the thrust force by installing a discharge pressure inducting closed space or the like which inducts such a working fluid that is formed in an interval between a rotor and, for example, a suction side bearing member and raised up to the extent of discharge pressure. CONSTITUTION:A compression mechanismic part 11 is provided with a cylinder 2, where both axial ends are opened, and a piston 12 being eccentrically set up in this cylinder 2 and rolled with a spiral blade 3 in a groove 3a on the circumferential part. In addition, a main bearing 13 as a suction side bearing member and an auxiliary bearing 14 as a discharge side bearing member both are fitted in this compression mechanism 11. In this case, a discharge pressure interspace 18 is formed in an interval between a recess part 19 opening to a suction side end face of the piston 12 and a projection 21 being installed in an inner end face 20 of the main bearing 13 and fitted in the recess part 19. Furthermore, a suction pressure space 23 is formed in an interval between a recess part 24 opening to a discharge side end face of the piston 12 and a projection 26 being installed in an inner end face 25 of the auxiliary bearing 14.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fluid compressor that compresses refrigerant gas in, for example, a refrigeration cycle.

(Prior Art) For example, the type of fluid compression a! (hereinafter referred to as a compressor) has been proposed by the applicant. And, this type of compressor has: Compression mechanism section 1 as shown in Figure ii3.
It is equipped with

That is, the compression mechanism section 1 has a cylinder 2 with both axial ends open, and a spiral groove 3a that is eccentrically arranged in the cylinder 2 and formed at a gradually decreasing pitch on the outer periphery of the cylinder 2. Helical blade 3 in groove 38
It has a cylindrical piston 4, which is a rotating body, and is wound with a cylinder. Furthermore, the compression mechanism section 1 has a main bearing 5 as a suction side bearing member on the suction end side of the cylinder 2, that is, on the right side in the figure, and a discharge side bearing on the discharge end side of the cylinder 2, that is, on the left side in the figure. A sub-bearing 6 is fitted as a member in an airtight manner.

Furthermore, the compression mechanism section 1 has a support shaft 7 that concentrically passes through the piston 3. The compression mechanism section 1 has the suction side end of the support shaft 7 inserted into the main bearing 5.
The discharge side end of the bearing 6 is passed through the sub bearing 6. The compression mechanism section 1 connects the sub-bearing 6 to the support shaft 7 via a locking pin 9 inserted into the connection protrusion 8 of the sub-bearing 6 and the support shaft 7 .

The compression mechanism section 1 has a main bearing 5 coupled to an inner wall surface of a closed case (not shown), and is supported in a cantilever manner within the closed case. Further, the compression mechanism section 1 holds the sub-bearing 6 in a floating state in a free state relative to the case.

The compression mechanism section 1 is driven by a driving means such as a motor, and rotates the cylinder 2 and the piston 4 relatively and synchronously while moving the blade 3 in and out of the piston 4 in the radial direction. Then, for example, refrigerant gas in a refrigeration cycle is sequentially fed into the working chamber 10, which is partitioned by blades 3 and whose volume gradually decreases from the suction end side to the discharge end side of the cylinder 2, and this refrigerant gas is transferred. Compress while doing so.

(Problem to be Solved by the Invention) By the way, when the sub-bearing 6 is connected to the support shaft 7 as described above,
In the compressor A of the type in which the secondary bearing 6 is held in a floating manner, the compression mechanism section 1
A thrust force is generated that acts from the discharge side to the suction side. Then, this thrust force armor is calculated as follows: (Pd -Ps)(Sd-Se).

Therefore, a thrust bearing is required, which increases the number of parts, and there are problems in that friction loss occurs due to the thrust force.

An object of the present invention is to provide a fluid compressor that can balance thrust force without increasing the number of parts and prevent friction loss caused by thrust force. .

[Structure of the Invention] (Means and operations for solving the r!i problem) In order to achieve the above object, the present invention provides a cylinder having a suction end side and a discharge end side, and an eccentric arrangement in the cylinder. It has a spiral groove formed on its outer periphery at a pitch that gradually decreases from the suction end side to the discharge end side of the cylinder, and a piston with a spiral blade fitted into this groove and the suction side of the cylinder. A suction side bearing member that is airtightly fitted to the end side and supports the cylinder in a cantilevered manner within the sealed case, and a suction side bearing member that is placed inside the cylinder and has one end inserted into the suction side bearing member and passes concentrically through the rotating body. The compression mechanism includes a support shaft that supports the rotating body, and a discharge side bearing member that fits on the discharge end side of the cylinder and is integrally connected to the support shaft. In a fluid compressor that compresses the working fluid sucked into the cylinder by rotating the cylinder while gradually transferring it from the suction end side to the discharge end side of the cylinder, the compressor is formed between the rotating body and the suction side bearing member until it reaches the discharge pressure. At least one of a closed space for introducing discharge pressure to introduce increased working fluid and a closed space for introducing suction pressure formed between the rotating body and the discharge side bearing member to introduce working fluid at suction pressure is provided. That's true.

By doing this, the present invention can balance the thrust force without increasing the number of parts, and furthermore,
The purpose is to reduce friction loss caused by thrust force.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2. Components that are the same as those described in the prior art section are given the same numerals and their explanations will be omitted.

FIG. 1 shows a main part of an embodiment of the present invention, and the reference numeral A in the figure indicates a fluid compressor (for example, a fluid compressor (
(hereinafter referred to as a compressor), and reference numeral 11 indicates a compression mechanism section provided in this compressor A and supported in a cantilever in a closed case (not shown).

The compression mechanism section 11 includes a cylinder 2 with both axial ends open, and a spiral groove 38 arranged eccentrically in the cylinder 2 on the outer periphery, and a spiral blade 3 fitted into the groove 38. Piston 1 as a cylindrical rotating body
It has 2. Furthermore, the compression mechanism section 11 includes a stepped cylindrical main bearing 13 as a suction side bearing member that is hermetically fitted to the suction end side of the cylinder 2, and a main bearing 13 that is airtightly fitted to the discharge end side of the cylinder 2. It has a sub-bearing 14 as a discharge-side bearing member, which is also fitted with a stepped cylindrical shape.

Here, in FIG. 1, the compression mechanism section 11 has its suction end side facing the right side in the figure, and its discharge end side facing the left side in the figure.

Further, in the compression mechanism section 11, a round bar-shaped support shaft 7 having substantially the same diameter over its entire length is passed through the piston 12 concentrically. Then, the compression mechanism section 11 inserts the suction side end of the support shaft 14 into the main bearing 13 to reach a midway point in the axial direction of the main bearing 13 .

Further, in the compression mechanism section 11 , the discharge side end of the support shaft 7 passes through the sub bearing 14 . A distal end portion 15 on the discharge side of the support shaft 7 is made to protrude substantially perpendicularly from an outer end surface 16 of the sub-bearing 14. The compression mechanism section 11 connects the sub-bearing 14 to the support shaft 7 via a locking pin 9, which will be described later, and holds the sub-bearing 14 in a floating manner by the support shaft 7.

The locking pin 9 is formed into a cylindrical shape, for example, and passes through the tip 15 of the support shaft 7.

Furthermore, the locking pin 9 has both ends connected to a support shaft 7 provided on the outer end surface 16 of the sub-bearing 14 and protruding from the outer end surface 16.
A connecting protrusion 17.1 arranged to sandwich the tip 15 of the
It is plugged into 7. The locking pin 9 is attached to the sub-bearing 14 so that it does not fall off the connecting protrusion 17.17.
is fixed.

Here, the reference numeral 2a in the figure indicates a drive pin that is protruded from the inner surface of the cylinder 2, engages with the piston 12, and transmits the rotational force of the cylinder 2 to the piston 12.

Moreover, what is indicated by the reference numeral 18 in FIG. 1 is a closed space for introducing discharge pressure (hereinafter referred to as discharge pressure space). This discharge pressure space 18 includes a recess 19 for forming a circular path-shaped space provided on the suction side of the piston 12 and opening at the suction side end face of the piston 12, and a recess 19 for forming a space in the form of a circular path, and a recess 19 for forming the space by vertically disposed on the inner end face 20 of the main bearing 13. It is formed between the space-forming protrusion 21 and the space-forming protrusion 21 that fits into the recess 19.

Further, the discharge pressure space 18 communicates with the internal space of the sealed case via a discharge pressure balance passage 22 formed inside the main bearing 13 and extending along the radial and axial directions of the main bearing 13. The discharge pressure space 18 introduces refrigerant gas as a working fluid that has been transferred and compressed by the compression mechanism section 11 to reach a discharge pressure (hereinafter referred to as Pd) and is discharged into the sealed case. Pd is applied to the wall surrounding 18.

Moreover, what is indicated by the reference numeral 23 in FIG. 1 is a closed space for introducing suction pressure (hereinafter referred to as suction pressure space). This suction pressure space 23 includes a recess 24 for forming a circular path-shaped space that is provided on the discharge side of the piston 12 and opens at the discharge side end surface of the piston 12, and a recess 24 that is vertically provided on the inner end surface 25 of the sub-bearing 14 to form the space. It is formed between the space-forming protrusion 26 and the space-forming protrusion 26 that fits into the recess 24 for use.

Further, the suction pressure space 23 forms a part of the working chamber lO through a suction pressure balance passage 27 that is formed inside the piston 12 and extends along the radial and axial directions of the piston 12. It communicates with a suction chamber 10a located on the suction side of the chamber.

Then, the suction pressure space 23 introduces refrigerant gas that is sucked into the suction chamber 10g and is at a suction pressure (hereinafter referred to as Ps),
Ps is applied to the wall surface surrounding the suction pressure space 23.

The discharge pressure space 18 and the suction pressure space 23 have their respective cross-sectional areas Sb and Sa, together with the cross-sectional area Sc of the support shaft 7 and the inner diameter cross-sectional area Sd of the cylinder 2, so as to satisfy the following formula: Sd+5c-5a+Sb-■ It is set.

That is, in the fluid compressor A having such a configuration, Pd and P
s causes the compression mechanism section 11 to generate a force acting from the discharge side to the suction side and a force acting from the suction side to the discharge side, respectively. Then, the force acting from the discharge side to the suction side is expressed as Pd (Sd-Sa) 10Ps (Sa-Sc)-〇.

Also, the force acting from the suction side to the discharge side is Pd (Sb
-5c)+Ps (Sd-5b)-■.

Then, if ■−■, Pd (Sd-5a)+Ps (Sa-5c)-P
d (Sb-5c)+Ps (Sd-8b), and when deformed, Pd (Sd+5c-3a-3b) +Ps (Sa5b-8e-3d)=0(Pd-Ps
)(Sd+5c-9a-5b)-0-■.

In order to make the formula (2) hold true in any case where Pd-Ps is, it is sufficient to set the equation as follows.

Therefore, as described above, the discharge pressure space 18 and the suction pressure space 23 are provided, and their sizes are Sd+5c-5a+S.
It is set to satisfy the relationship b, and furthermore, the discharge pressure space 18
11: While guiding the Pd refrigerant gas, the suction pressure space 23
By guiding the refrigerant gas Ps to , the thrust force acting on the compression mechanism section 11 can be balanced.

In addition, the thrust force can be balanced without providing a thrust bearing or the like that receives unbalanced thrust force, and the thrust force acting from the discharge side to the suction side can be received only by the locking pin 9. There is no need to increase the number of parts to maintain balance.

Furthermore, friction loss caused by thrust force can be reduced, and electrical input can be set low.

Note that even if the formula (2) does not completely hold true, the thrust force can be reduced and the same effects as those described above can be obtained.

Furthermore, in this embodiment, two closed spaces are provided: a discharge pressure space 18 disposed on the suction side of the compression mechanism section 11 and a suction pressure space 23 disposed on the discharge side. However, the present invention is not limited to this, and for example, either one of the double opening spaces 18 and 23 may be provided. Even when only one of the double opening spaces 18.23 is provided, it is possible to reduce the thrust force.

Furthermore, in this embodiment, the piston 12 side is made concave in order to form the suction pressure space 23, and the bearings 13 and 14 sides are made convex, but the present invention is not limited to this. For example, a convex portion may be provided on at least one end of the piston 12, and this convex portion may be fitted into a concave portion formed in a corresponding bearing.

Further, the application of the fluid compressor of the present invention is not limited to refrigeration cycles.

[Effects of the Invention] As explained above, the present invention has a cylinder having a suction end side and a discharge end side, in which a piston having a spiral blade wound thereon is arranged eccentrically, and the suction end side is placed on the suction end side of the cylinder. The cylinder is cantilever-supported by the bearing member on the suction side by fitting the bearing member airtightly, and the support shaft, whose one end is inserted into the bearing member on the suction side, is passed concentrically through the rotating body, and the cylinder is discharged. A compression mechanism unit is provided in which a discharge end bearing member is airtightly fitted to the end side, and this discharge end bearing member is integrally connected to a support shaft, and the cylinder and the rotating body are rotated relative to each other. In a fluid compressor that compresses the sucked working fluid while gradually transferring it from the suction end side to the discharge end side of the cylinder,
A closed space for introducing discharge pressure, which is formed between the rotating body and the suction side bearing member, and introduces working fluid raised to the discharge pressure, and a working fluid at the suction pressure, which is formed between the rotating body and the discharge side bearing member. At least one of the closed spaces for introducing suction pressure is provided.

Therefore, the present invention has the effect of being able to balance the thrust force without increasing the number of parts, and further reducing the friction loss caused by the thrust force.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention,
FIG. 1 is a sectional view showing the main parts, FIG. 2 is an exploded sectional view showing the main parts, and FIG. 3 is a sectional view showing a conventional example.

Claims (1)

[Claims] A cylinder having a suction end side and a discharge end side, and a spiral groove arranged eccentrically in the cylinder and formed on its outer circumference at a pitch that gradually decreases from the suction end side to the discharge end side of the cylinder. a piston having a spiral blade fitted into the groove; a suction side bearing member that is airtightly fitted to the suction end side of the cylinder and supports the cylinder in a cantilever manner within the sealed case; A support shaft disposed within the cylinder and having one end inserted into the suction side bearing member and penetrating the rotary body concentrically to support the rotary body; and a support shaft that is airtightly fitted to the discharge end side of the cylinder. A compression mechanism unit includes a discharge side bearing member integrally connected to the support shaft, and the cylinder and the rotary body are rotated relatively, and the working fluid sucked into the cylinder is transferred to the cylinder. In a fluid compressor that compresses fluid while gradually transferring it from the suction end side to the discharge end side, a discharge pressure introducing device is formed between the rotary body and the suction side bearing member and introduces working fluid raised to the discharge pressure. A fluid compressor comprising at least one of a closed space and a suction pressure introducing closed space formed between the rotating body and the discharge side bearing member and introducing working fluid at suction pressure. .