JP3102175B2 - Reciprocating compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a reciprocating compressor suitable for use in vehicle air conditioning.

[0002]

2. Description of the Related Art Conventionally, each piston reciprocates in a plurality of bores formed in a cylinder block in parallel with a drive shaft, as in a swash plate compressor described in Japanese Patent Application Laid-Open No. Sho 59-145378, for example. Compressors that compress refrigerant gas are known. In this type of compressor, a drive shaft is fitted and supported in a central shaft hole of a cylinder block, and each piston is linked to a swash plate in a crank chamber that cooperates with the drive shaft to move directly in each bore. A housing is joined to the end surface of the cylinder block via a valve plate, and a suction chamber for supplying refrigerant gas into the bore and a discharge chamber for discharging refrigerant gas compressed by a piston in the bore are formed in the housing. Is formed. The suction of the refrigerant gas from the suction chamber into the bore is performed by moving the piston to the bottom dead center position, and by setting the suction port formed in the valve plate and the pressure in the bore provided on the bore side of the suction port. And a suction valve that opens a suction port in response to the pressure. Further, the discharge of the refrigerant gas from the bore to the discharge chamber is performed by moving the piston to the top dead center position, the discharge port formed in the valve plate, and the discharge port provided on the discharge chamber side of the discharge port inside the bore. This is performed via a discharge valve that opens a discharge port according to pressure.

[0003]

However, in the conventional compressor, the suction valve is configured to overcome its own elastic force acting in the direction of maintaining the valve closed state and to open the valve. Is big. This pressure loss leads to a decrease in volumetric efficiency. Therefore, the present applicant has filed Japanese Patent Application No. Hei.
No. 31853 proposed a reciprocating compressor having excellent volumetric efficiency. In this compressor, a conduction path that radially communicates each bore with the central shaft hole is formed, and a rotary valve is coupled to the drive shaft so as to be able to rotate synchronously. The rotary valve is formed with a suction passage that sequentially connects the passage of each bore in the suction stroke and the suction chamber. In the proposed compressor, the rotation valve rotates in synchronization with the drive shaft, so that the refrigerant gas in the suction chamber is sequentially sucked into each bore, and the suction operation of the refrigerant gas continues smoothly and stably in each bore. Therefore, the pressure loss is extremely reduced. Thus, in this compressor,
With a fixed capacity, sufficient volumetric efficiency can be maintained regardless of a variable capacity.

[0004] However, in order to secure the strength at the time of transmitting the driving force, the drive shaft needs to be made of an iron-based metal, while from the viewpoint of reducing the weight of the compressor as much as possible, the rotary valve is made of an aluminum-based metal. preferable. Here, if the drive shaft made of an iron-based metal and the rotary valve made of an aluminum-based metal interfere with each other when the drive shaft rotates, the rotary valve will be damaged and the synchronous rotation of the rotary valve will be impaired. For this reason, in the Japanese Patent Application No. 3-238402, the present applicant has disclosed a rotary valve having a cylindrical outer member having an opening on an outer peripheral surface, and a suction passage formed by the opening and the inner surface; An inner member press-fitted into the crank chamber side and fitted to the engagement shaft portion of the drive shaft is employed. The outer member is made of an aluminum-based metal, and the inner member is made of an iron-based metal.

However, in this compressor, since the inner member having a large volume is press-fitted into the outer member, the outer diameter of the outer member changes, and it becomes necessary to rework the entire rotary valve after the press-fitting. For this reason, the production cost has risen due to the additional steps. Further, in this compressor, the weight of the rotary valve increases due to the inner member having a large volume, which results in impairing the weight reduction of the compressor.

SUMMARY OF THE INVENTION It is an object of the present invention to maintain a sufficient volumetric efficiency and to surely reduce the weight of a compressor while reducing manufacturing costs.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, a reciprocating compressor according to the present invention has a cylinder block having a plurality of bores around an axis, and a bearing fitted into a shaft hole of the cylinder block. A drive shaft, a piston linked to a swash plate in a crank chamber cooperating with the drive shaft, and linearly moving in the bore, a suction chamber communicating with the shaft hole, and an outer region of the suction chamber. A reciprocating compressor including a housing having a closed discharge chamber and closing an end surface of the cylinder block, a conduction path is formed between each of the bores and the shaft hole, and the drive shaft is A rotary valve having a suction passage for sequentially communicating the passage of each bore in the suction stroke with the suction chamber is connected to be synchronously rotatable, the drive shaft is an iron-based metal, and the rotary valve is an aluminum-based It is made of metal, and a pair of A first engaging groove having a flat surface is bored, and a key having a matching opposing flat surface is fitted into the first engaging groove portion, and the key has a matching opposing flat surface and is drilled at the drive shaft end. A new configuration is adopted in which the second engagement groove portion is fitted.

[0008]

In the reciprocating compressor of the present invention, the rotation valve rotates in synchronization with the drive shaft, so that the refrigerant gas in the suction chamber flows through the suction passage of the rotation valve and the passages of the respective bores in the suction stroke. Thus, the suction operation of the refrigerant gas is smoothly and stably continued in each bore, so that the pressure loss is extremely reduced.

Further, in this compressor, the driving shaft is made of an iron-based metal, so that the strength at the time of transmitting the driving force is secured, and the rotary valve is made of an aluminum-based metal, so that the weight is reduced. Here, in this compressor, a key is formed between an opposing plane of the first engagement groove formed in the end part circumferential side of the rotary valve and an opposing plane of the second engagement groove formed in the drive shaft end. Are fitted to each other to connect the drive shaft and the rotary valve. At this time, the rotary valve made of aluminum-based metal receives torque from the drive shaft at a position as far as possible from the shaft center because the first engagement groove portion is bored on the end circumferential side. And the arm length of the moment can be increased, so that deformation is less likely to occur.
Thus, the torque from the drive shaft is transmitted to the rotary valve via the key while preventing the rotary valve from being damaged, and the synchronous rotation is not impaired.

Further, even if the key is interposed between the drive shaft and the rotary valve, the outer diameter of the rotary valve does not change as in the previous proposal, and no post-processing is required. Further, the key is relatively lightweight, and the sum of the rotary valve and the key does not increase so much, and the weight reduction of the compressor is not impaired.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, reference numeral 1 denotes a cylinder block having a central shaft hole 1a penetrating in the axial direction and six bores 1A to 1F, and a front housing 2 is joined to one end surface of the cylinder block 1, A rear housing 4 is joined to the other end surface via a ring-shaped valve plate 3. A drive shaft 6 made of an iron-based metal is provided in the crankcase 5 in the front housing 2.
And the central shaft hole 1 of the cylinder block 1
a and is rotatably supported. A rotor 7 is fixed on the drive shaft 6, and a long hole 8 a penetrates a distal end of a support arm 8 extending to the rear side of the rotor 7. A pin 8b is slidably fitted into the elongated hole 8a, and a swash plate 9 is slidably connected to the pin 8b.

A sleeve 10 is loosely fitted on the drive shaft 6 adjacent to the rear end of the rotor 7, and is constantly urged toward the rotor 7 by a coil spring 11 and protrudes from the left and right sides of the sleeve 10. A pivot 10a (only one is shown) is fitted into an engagement hole (not shown) of the swash plate 9, and the swash plate 9 is supported so as to be able to swing around the pivot 10a. A rocking plate 12 is supported on the rear side of the swash plate 9 via a thrust bearing or the like.
The rotation of the rocking plate 12 is restricted by a notch (not shown). In addition, six connecting rods 14 are moored at equal intervals on the outer edge of the swing plate 12, and each connecting rod 14 has a bore 1A to 1A.
It is moored with the piston 15 in 1F. Therefore,
The rotational movement of the drive shaft 4 is converted into forward and backward swing of the swing plate 12 by the intervention of the rotor 7 and the swash plate 9, and each piston 15 reciprocates in the bores 1 </ b> A to 1 </ b> F. The stroke of the piston 15 and the tilt angle of the rocking plate 12 are changed in accordance with the pressure difference from the suction pressure. The pressure in the crank chamber 5 is controlled by a control valve (not shown) provided in the rear housing 4 based on the cooling load.

The rear housing 4 is provided with a suction chamber 17 which is open at the rear end face at the center and communicates with the central shaft hole 1a of the cylinder block 1. Are formed. Valve plate 3
Has a discharge port 3 communicating with the head of each of the bores 1A to 1F.
a, and a retainer 21 is interposed between the discharge port 3a and the discharge chamber 18 via a discharge valve 20.

Further, in the cylinder block 1, as shown in FIG. 2, conduction paths 2A to 2F are formed radially between the bores 1A to 1F and the central shaft hole 1a. As shown in FIG. 3, a cylindrical rotary valve 22 made of an aluminum-based metal that slides on the central shaft hole 1a via a key 23 is attached to the end of the drive shaft 6 extending into the central shaft hole 1a. ing.
That is, the flange 22 a is provided on the end circumferential side of the rotary valve 22.
The flange 22a is provided with a first engaging groove 22b having an opposing flat surface and diametrically formed in the flange 22a. A second engaging groove 6a having an opposing plane is also formed in the end of the drive shaft 6 in the diametrical direction. The opposing plane of the first engagement groove portion 22b in these rotary valves 22 and the drive shaft 6
The key 23 is fitted in such a manner that the opposing planes coincide with the opposing planes of the second engaging groove 6a.

As shown in FIG. 1, the rotary valve 22 has an opening formed at a predetermined angle communicating with the inner surface, and the opening and the inner surface define a suction passage 25 communicating with the suction chamber 17. I have. The rear side of the rotary valve 22 is supported on the inner wall of the suction chamber 17 via a thrust bearing. The compressor configured as described above is disposed in a circuit as a vehicle air conditioning refrigeration apparatus and is used.

When the compressor is operated and the drive shaft 6 rotates, the swash plate 9 swings while rotating together with the drive shaft 6, and the swing plate 12 rotates in a state where the rotation of the swing plate 12 is regulated with respect to the swash plate 9. Only the oscillating motion is performed, so that the piston 15
Reciprocate in 1F. When the piston 15 starts moving from the top dead center toward the bottom dead center in the bores 1A to 1F, the bores 1A to 1F enter a suction stroke. Also, bore 1A
If the piston 15 starts moving from the bottom dead center toward the top dead center within 1F, the bores 1A-1F enter the compression / discharge stroke.

Here, as shown in FIG.
The direction torque is transmitted from the second engagement groove 6a to the key 23, and the M direction torque of the key 23 is transmitted from the first engagement groove 22b to the rotary valve 22. In this way, the rotary valve 22 is rotated in the direction indicated by the arrow in FIG. 2 in synchronization with the drive shaft 6 via the key 23, so that the bores 1A to 1F in the suction stroke are rotated.
The refrigerant passages 2A to 2F communicate with the suction passage 25, and the refrigerant gas in the suction chamber 17 flows through the suction passage 25 and the conduction passage 2A.
To 2F, and is sequentially sucked into each of the bores 1A to 1F.

Thereafter, if the rotation of the rotary valve 22 causes each of the bores 1A to 1F to be in the compression / discharge stroke, their conduction paths 2A to 2F do not communicate with the suction path 25, and It is closed. At this time, the pressure in the bores 1A to 1F during the compression stroke is still lower than the pressure in the discharge chamber 18, and the discharge valve 20 is closed. Also, the bores 1A to 1F in the discharge stroke do not communicate with the suction passage 25 in the conduction passages 2A to 2F, and are closed by the seal portion of the rotary valve 22. However, at this time, the pressure in the bores 1A to 1F in the discharge stroke becomes higher than the pressure in the discharge chamber 18, and the discharge valve 20 is opened.

In this way, the respective bores 1A to 1F sequentially repeat the suction, compression and discharge strokes via the rotary valve 22 which rotates in synchronization with the reciprocating movement of the piston 15. At this time, the bores 1A to 1F in the suction stroke are communicated with the suction chamber 17 through the conduction paths 2A to 2F and the suction passage 25, and the suction operation of the refrigerant gas is continued smoothly and stably. Is made very small. Therefore, in this compressor, sufficient volumetric efficiency can be maintained.

Further, in this compressor, since the drive shaft 6 is made of an iron-based metal, the strength at the time of transmitting the driving force is secured, and since the rotary valve 22 is made of an aluminum-based metal, the weight is reduced. Here, in this compressor, even if the rotary valve 22 is made of an aluminum-based metal, the first engagement groove portion 22b is formed on the end circumferential side, so that the position is as far as possible from the axis. Can receive the torque from the drive shaft 6 and the arm length of the moment can be increased, so that deformation is less likely to occur. Thus, the torque from the drive shaft 6 is reliably transmitted to the rotary valve 22 via the key 23 while preventing the rotary valve 22 from being damaged,
Synchronous rotation is not impaired.

Further, in this compressor, even if the key 23 is interposed between the drive shaft 6 and the rotary valve 22, the outer diameter of the rotary valve 22 does not change as in the previous proposal, and post-processing is required. do not do.
Further, the key 23 is relatively lightweight, and the sum of the rotary valve 22 and the key 23 does not increase so much, and the reduction in weight of the compressor is not impaired. Accordingly, in this compressor, sufficient volumetric efficiency can be maintained, and the post-processing of the rotary valve 22 as in the above proposal is not required, so that the manufacturing cost can be reduced, and the rotary valve 22 and the key can be combined. Since the weight does not increase even in the total of 23, the weight of the compressor can be reliably reduced.

In this compressor, a disc spring can be provided on the crank chamber 5 side if interference with the key 23 is avoided.

[0023]

As described in detail above, the reciprocating compressor of the present invention employs the configuration described in the claims, so that sufficient volumetric efficiency is maintained and the manufacturing cost is reduced. Thus, the weight of the compressor can be reduced reliably.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a compressor according to an embodiment.

FIG. 2 is a cross-sectional view of the compressor according to the embodiment.

FIG. 3 is an exploded perspective view of a main part of the compressor according to the embodiment.

FIG. 4 is a sectional view of a main part of the compressor according to the embodiment.

[Explanation of symbols]

1: Cylinder block 1a: Central shaft hole 1A
~ 1F ... Bore 3 ... Valve plate 4 ... Rear housing 6 ...
Drive shaft 5 ... Crank chamber 9 ... Swash plate 15
... Piston 17 ... Suction chamber 18 ... Discharge chamber 2A
２2F: conduction path 22: rotary valve 25: suction path 22
b: first engagement groove 23: key 6a: second engagement groove

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Osamu Hiramatsu 2-1-1, Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (58) Field surveyed (Int. Cl. ⁷ , DB name) F04B 27 / 08 F04B 39/10

Claims (1)

(57) [Claims] A cylinder block having a plurality of bores around an axis, a drive shaft fitted and supported in a shaft hole of the cylinder block, and a swash plate in a crank chamber cooperating with the drive shaft. And a housing having a suction chamber communicating with the shaft hole and a discharge chamber formed outside the suction chamber to close an end face of the cylinder block. In the reciprocating compressor, a conduction path is formed between each of the bores and the shaft hole, and a suction path that sequentially communicates with the drive shaft the conduction path of each of the bores in a suction stroke and the suction chamber. The drive shaft is made of an iron-based metal, the rotary valve is made of an aluminum-based metal, and the first end of the rotary valve has an opposing flat surface on the circumferential side. An engagement groove is drilled,
A key having a matching opposing plane is fitted into the first engaging groove, and the key is fitted with a second engaging groove formed in the end of the drive shaft having a matching opposing plane. Reciprocating compressor.