JPH0240316Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a variable displacement compressor, in particular, a compression element having a front head, a rear head, and a cylinder is fixed in a housing by press fitting, and the compression element is provided with an opening into a cylinder chamber. The present invention relates to a variable displacement compressor in which a valve hole with an intermediate port is provided, a capacity control valve for opening and closing the intermediate port is installed in the valve hole, and the capacity is controlled by opening and closing the capacity control valve.

Conventionally, this type of compressor has already been proposed as shown in the specification and drawings of Japanese Patent Application No. 1983-36207 filed by the present applicant (see Japanese Patent Publication No. 62-45456). . To roughly explain this compressor based on FIG. 1, the front head 30,
An intermediate port 3 that opens into a cylinder chamber 34 is provided in the rear head 31 of the compression element A, which is equipped with a cylinder 33 that is press-fitted into the rear head 31 and housing 32.
A valve hole 36 with a diameter of 5 is provided, and a capacity control valve 37 is installed inside this valve hole 36.
A back pressure passage 39 opening from the back pressure chamber 38 to the outer wall of the cylinder 33 is formed, and a back pressure pipe 40 is penetrated into the housing 32 to
It is attached to the opening of No. 9 by press fitting.

As such, this compressor has a housing 32
A back pressure pipe 40 is connected to the outer wall of the cylinder 33 that is press-fitted into the rear head 31, and a displacement control valve 37 is connected to the rear head 31.
Since the connection part of the back pressure pipe 40 is provided with
The back pressure passage 39 leading to the cylinder 33 and the rear head 31 has an extremely complicated shape passing through the inside of the cylinder 33 and the rear head 31, and there is a problem in that the number of man-hours for machining the cylinder 33 and the rear head 31 increases.

Therefore, the cylinder that is press-fitted into the housing has an intermediate port that opens into the cylinder chamber, and a valve hole is formed horizontally so as to open on the outer wall of the cylinder, and a capacity control valve is inserted into the valve hole. It is conceivable to connect a back pressure pipe to the opening.

However, in a so-called subassembly state in which the front head, cylinder, and rear head of the compression element are stacked and assembled and then the capacity control valve is inserted into the valve hole of the cylinder, the capacity control valve tends to fall off from the cylinder. This results in the problem of poor assembly workability.

Therefore, in order to solve the problem of the capacity control valve falling off, a valve cover is installed on the back pressure chamber side of the capacity control valve inserted into the valve hole of the cylinder, and a valve cover is installed to prevent the valve from falling off. communicates a passage opening on one side of the valve hole position in the cylinder outer wall,
Further, it is conceivable that after press-fitting and fixing into the housing, a back pressure pipe may be connected to the opening of this passage.

However, in order to simplify the back pressure passage of the back pressure chamber of the capacity control valve, even though the cylinder is provided with the capacity control valve, the cylinder has a valve hole with a back pressure chamber and a connection hole for the back pressure pipe. Since these are provided separately, it is inevitable that the back pressure passage of the back pressure chamber will become complicated.

The purpose of the present invention is to insert a capacity control valve into a valve hole opening in the outer wall of a cylinder in a compression element, provide a cylindrical valve cover in the back pressure chamber of the control valve, and create a subassembly state. After press-fitting and fixing this state into the housing, a back pressure pipe is connected to the valve cover, thereby preventing the capacity control valve from falling off in the sub-assembly state and simplifying the back pressure passage to the back pressure chamber. To provide a variable displacement compressor that can reduce the total number of processing steps, improve assembly workability, and provide good sealing performance for control pressure introduced into a back pressure chamber.

Therefore, the configuration of the present invention is such that the front head 5
a. A compression element A having a rear head 5b and a cylinder 6 is fixed in the housing 1 by press fitting, and the compression element A is provided with a valve hole 7 having an intermediate port 7a that opens into the cylinder chamber 6a. 7
In addition, a capacity control valve V for opening and closing the intermediate port 7a is installed, and a back pressure pipe 11 is connected to the back pressure chamber 10 of the capacity control valve V, so that the capacity is controlled by opening and closing the capacity control valve V. In the compressor,
The cylinder 6 is provided with the valve hole 7, and the valve hole 7 is opened in the outer wall of the cylinder 6.
A valve cover 15 having an insertion hole 13 of the inlet tube 12 and a communication hole 14 opening to the back pressure chamber 10 is attached to the outer wall opening of the valve hole 7, and the outer surface of the valve cover 15 is connected to the cylinder 6. The inlet tube 12 is press-fitted into the outer surface of the housing 1 in a non-protruding manner, and the inlet tube 12 is press-fitted into the insertion hole 13 located in the valve hole 7, and the inlet tube 12 is press-fitted into the valve cover 15. The back pressure pipe 11 is connected through the inlet tube 12, and the inlet tube 12 and the valve cover 1 are connected to each other.
5 overlaps with the press-fitted part between the valve cover 15 and the valve hole 7, it is possible to reduce the number of machining steps and improve assembly workability, and to seal the control pressure well. did.

An embodiment of the compressor of the present invention will be explained based on FIGS. 2 and 3.

The one shown in Figures 2 and 3 is a high-pressure dome type rotary compressor, and in Figures 1 and 2, 1
This housing has a lid plate 1b on the upper part of the body 1a and a bottom plate 1c on the lower part.A suction pipe 2 is attached to the body 1a, and a discharge pipe 3 is attached to the lid plate 1b.

4, a rotor 4a is mounted on the upper part of the housing 1.
By protruding the drive shaft 4b downward, the stator 4c
This is a motor supported by press-fitting.

Further, A is a compression element constructed by integrally assembling a front head 5a, a rear head 5b, and a cylinder 6 having a rotor 6a sandwiched between these two heads 5a, 5b in a triple form by means of a connecting member a. , a cylinder 6 is press-fitted to support the lower part of the housing 1, and the drive shaft 4b is supported by a rotor 6.
It is rotatably connected to a.

Further, in this compression element A, a suction port 6c and a discharge port 6d communicating with the cylinder chamber 6b are formed in the cylinder 6 and the front head 5a, and the suction pipe 2 communicates with the suction port 6c.
A discharge port 6d is opened outward to the front head 5a, and by driving the rotor 6a, suction gas is sucked into the cylinder chamber 6b from the suction pipe 2 through the suction port 6c and compressed, thereby producing an amount corresponding to the full load capacity. The compressed gas is supplied to the motor 4 from the discharge port 6d.
It is designed to be discharged from the discharge pipe 3 through the inside.

This compression element A has a cylinder chamber 6b.
A valve hole 7 is provided with an intermediate port 7a that opens into the valve hole 7, and this valve hole 7 is connected to the suction port 6c through a bypass passage 8, and a capacity control valve V that opens and closes the intermediate port 7a is provided in the valve hole 7. Hey, Bullet 9
A back pressure pipe 11 is connected to a back pressure chamber 10 of the capacity control valve V.

Then, by applying high control pressure to the back pressure chamber 10 from the back pressure pipe 11 and closing the capacity control valve V, operation at full load capacity is performed.
By applying low control pressure from the back pressure pipe 11 to open the capacity control valve V, a part of the refrigerant in the middle of the compression process in the cylinder chamber 6b is bypassed from the intermediate port 7a to the suction side, allowing operation at a low load capacity. I am trying to do it.

Therefore, in the variable displacement compressor constructed as described above, the present invention provides the valve hole 7 in the cylinder 6 of the compression element A that is press-fitted into the housing 1, and 6
A valve cover 15 is provided which is opened in the outer wall of the valve hole 7 and has an insertion hole 13 for the inlet tube 12 and a communication hole 14 which opens into the back pressure chamber 10 at the outer wall opening of the valve hole 7. The outer surface of the cylinder 6
The inlet tube 12 is press-fitted into the outer surface of the housing 1 in a non-protruding manner, and the inlet tube 12 is inserted into the insertion hole 13 located in the valve hole 7.
The back pressure pipe 11 is connected to the valve cover 15 through the inlet tube 12 by press-fitting the valve cover 15 into the valve hole 7. It overlaps with the press-fitted part.

Specifically, as shown in FIGS. 2 and 3, the valve hole 7 has its intermediate port 7a provided in the inner circumferential wall of the cylinder chamber 6b of the cylinder 6 between the suction port 6c and the discharge port 6d. , from this intermediate port 7a to the valve seat 7 laterally via the valve seat 7b.
It is provided so as to open at the outer wall of the cylinder 6 with a constant inner diameter larger than b.

Further, the valve cover 15 is tightly fixed to the outer wall opening of the valve hole 7 by press fitting to receive the capacity control valve V which is biased in the opening direction by the bullet 7.

Further, the inlet tube 12 has a distal end portion inserted into the body portion 1a of the housing 1 fixed to the insertion hole 13 of the valve lid 15 by press fitting, and a portion protruding outward from the body portion 1a. A joint pipe 16 is provided around the outside of the inlet tube 16 to tightly fix it to the body part 1a, and the back pressure pipe 11 is inserted into the protruding end of the inlet tube 12 from the body part 1a. Pressure pipe 11 and joint pipe 1
Each gap with 6 is densely filled with brazing material and fixed by brazing.

Reference numeral 17 denotes a stroke adjustment protrusion of the capacity control valve V, which is provided on one side of the capacity control valve V and the valve lid 11 so as to protrude toward the other side, and is provided with a protrusion 17 for adjusting the stroke of the capacity control valve V. This is done to adjust the opening degree of the valve when it is opened, and to set a low load capacity value for the compressor capacity.

Further, 18 is a discharge valve, and 19 is a terminal.

The compressor of the present invention is constructed as described above, and during assembly work, the front head 5a, cylinder 6, and rear head 5b of the compression element A are assembled into a triple-layered structure using the connecting member a, and then the valve of the cylinder 6 is assembled. The ammunition 9 and the capacity control valve V are inserted into the hole 7, and the valve cover 15 is fixed to the opening of the outer wall of the valve hole 7, and the valve cover 15 is assembled into the housing 1 as a subassembly.

Therefore, when the subassembly is in this state, the capacity control valve V can be reliably prevented from falling out of the valve hole 7 of the cylinder 6 by the valve cover 15, and can be easily transported or stored in a storage location. When the compression element A is oriented in any direction or moved with any acceleration, the displacement control valve V can be normally held in the cylinder 6 without falling out. There is no problem that the outer surface of the valve cover 15 protrudes toward the housing 1 and becomes a hindrance, and the overall workability can be improved.

Furthermore, when the back pressure pipe 11 is connected to the compression element A via the inlet tube 12 after the subassembly is press-fitted into the body 1a, the members of the compression element A connected in this way are Since the cylinder 6 is press-fitted into the body 1a and equipped with a capacity control valve V, the inlet tube 12
The back pressure passage leading from the valve cover 15 to the back pressure chamber 10 only needs to be provided in the cylinder 6, and can be made extremely short and straight as a whole, and the number of man-hours for machining the back pressure passage can be greatly reduced. Processability can be improved.

Further, the inlet tube 12 is connected to the valve lid 1.
5, the inlet tube 12 can be made sufficiently thin regardless of the size of the valve hole 7. Therefore, during the brazing work, the brazing material is dripped onto the protruding end B of the inlet tube 12, and applied inwardly into each gap between the joint pipe 16 on the outer periphery of the inlet tube 12 and the back pressure pipe 11 on the inner periphery. When flowing, the inner and outer flow surfaces of the thin-walled inlet tube 12 can be quickly brought to a high temperature and maintained at this high temperature, thereby improving the workability of brazing.

Further, the inlet tube 12 is connected to the valve hole 7.
The inlet tube 12 is press-fitted into the insertion hole 13 located inside, and the part of the inlet tube 12 that is press-fitted into the valve cover 15 and the part of the valve cover 15 that is press-fitted into the valve hole 7 are arranged so that they overlap within the valve hole 7. Therefore, the sealing performance between the inlet tube 12 and the valve lid 15 as well as the sealing performance between the valve lid 15 and the valve hole 7 can be improved. This makes it possible to almost eliminate leakage of the control pressure introduced into the back pressure chamber 10.

Moreover, as mentioned above, the inlet tube 12
Since the press-fitted portion between the valve cover 15 and the valve hole 7 overlaps with the press-fitted portion between the valve cover 15 and the valve hole 7, the cylinder 6 is installed inside the housing 1 as a subassembly.
Afterwards, the inlet tube 12 is attached to the valve cover 15.
When the inlet tube 12 is press-fitted into the insertion hole 13 of the valve hole 7, it can be expected that the press-fitting of the inlet tube 12 also serves as a wedge against the press-fitting and fixing of the valve cover 15 into the valve hole 7. Since it can be firmly fixed to the valve hole 7, leakage of the control pressure introduced into the back pressure chamber 10 can be further prevented.

As described above, in the present invention, the cylinder of the compression element has an intermediate port that opens into the cylinder chamber, and a valve hole in which the capacity control valve is installed is provided so as to open on the outer wall of the cylinder, and the outer wall opening of the valve hole Since a valve cover with an insertion hole for the inlet tube and a communication hole opening into the back pressure chamber of the capacity control valve is attached, a sub-assembly with a capacity control valve and a valve cover installed in the cylinder of the compression element is installed. In the closed state, the displacement control valve is reliably prevented from falling out of the cylinder by the valve cover, and the compression element cannot be moved in any direction when being carried, stored in a storage location, or assembled into a housing. The capacity control valve can be held in the cylinder without falling off even when it is moved with acceleration in any direction, and there is no problem that the outer surface of the valve cover protrudes toward the housing side and gets in the way. This improves work efficiency.

In addition, the valve cover is attached to the outer wall opening of the cylinder in which the capacity control valve in the compression element is provided, and an inlet tube is provided in the insertion hole of the valve cover, and the back pressure pipe is connected to the tube. It is only necessary to form a back pressure passage for the pressure chamber in the cylinder,
Furthermore, since the overall length can be made extremely short, the number of man-hours required for machining the back pressure passage can be significantly reduced, and machinability can be improved.

Moreover, since the inlet tube is fixed to the valve hole through the valve cover, it can be made thin regardless of the size of the valve hole. Therefore, when connecting the back pressure pipe to the inlet tube by brazing, Heat can be quickly distributed to the inlet tube, improving the workability of brazing work. Furthermore, since the part of the inlet tube that is press-fitted into the valve cover and the part of the valve cover that is press-fitted into the valve hole are arranged to overlap within the valve hole, the inlet tube and the valve cover are This improves both the sealing performance between the valve cover and the valve hole, and the leakage of the control pressure introduced into the back pressure chamber can be almost eliminated.

Moreover, when the inlet tube is press-fitted into the insertion hole of the valve cover, the press-fitting of the inlet tube is
It can also be expected to serve as a wedge when the valve cover is press-fitted into the valve hole, and the valve cover can be firmly fixed to the valve hole, thereby preventing leakage of control pressure introduced into the back pressure chamber. can be further eliminated.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional explanatory diagram of the main parts showing a conventional example;
The figure is a sectional front view showing an embodiment of the present invention, and FIG. 3 is a sectional plan view taken along the line X--X in FIG. 2. 1...Housing, 5a...Front head,
5b...Rear head, 6...Cylinder, 6b...
Cylinder chamber, 7a... intermediate port, 7... valve hole,
10... Back pressure chamber, 11... Back pressure pipe, 12... Inlet tube, 13... Insertion hole, 14... Communication hole, 15... Valve cover, A... Compression element, V... Capacity control valve .

Claims (1)

[Scope of utility model registration request] A compression element A comprising a front head 5a, a rear head 5b and a cylinder 6 is fixed in the housing 1 by press fitting, and the compression element A is provided with a valve hole 7 having an intermediate port 7a opening into the cylinder chamber 6b. A capacity control valve V for opening and closing the intermediate port 7a is installed in the valve hole 7, and a back pressure pipe 11 is connected to the back pressure chamber 10 of the capacity control valve V, and the capacity is controlled by opening and closing the capacity control valve V. In a powerful compressor, the cylinder 6 is provided with the valve hole 7.
The valve hole 7 is opened in the outer wall of the cylinder 6, and the outer wall opening of the valve hole 7 is provided with a communication hole 14 that opens into the insertion hole 13 of the inlet tube 12 and the back pressure chamber 10. Valve lid 15 with
The outer surface of the valve cover 15 is press-fitted into the outer surface of the cylinder 6 that is press-fitted into the housing 1 in a non-protruding manner, and the inlet tube 12 is
The inlet tube 12 is press-fitted into the insertion hole 13 located in the valve hole 7 and inserted into the valve lid 15.
The back pressure pipe 11 is connected through
A variable displacement compressor characterized in that the press-fitted portion of the valve hole 7 overlaps with the press-fitted portion of the valve hole 7.