JPS623190A - Coolant compressor - Google Patents

Abstract

PURPOSE:To permit the capacity control through pulse electric conduction by installing a solenoid valve for directly opening and closing a coolant-gas passage which communicates to one suction hole between two suction holes for supplying coolant gas. CONSTITUTION:When the swithcing from full load operation to part load operation is performed, a secondary side coil 49 is put into pulse electric conduction, and when a magnetic field is applied in the direction for deenergizing the magnetic force of a permanent magnet 48, a movable iron-core 45 is separated from an iron-core receiving part 47 by the springy force of a bias spring 51, and a piston 46 contacts with a valve seat. At this time, an upstream-side flow passage 40 and a downstream-side flow passage 41 are cut off, and the supply of coolant gas into a cylinder 28 is carried out only through the first suction hole 38, and the refrigeration facul is reduced by the quantity of coolant gas which is not supplied from the second suction hole 39, and capacity control is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to capacity control of a refrigerant compressor used for cooling automobiles.

Conventional technology In recent years, there has been a strong demand for refrigerant compressors used for automobile air conditioning to control the discharge capacity of refrigerant gas according to the heat load in the vehicle interior, thereby saving energy and improving comfort. ing.

As a method for controlling the discharge capacity of this refrigerant gas, the present applicants have provided suction holes for supplying refrigerant gas in two locations in the cylinder, and have created a capacity to control the supply of refrigerant gas by blocking one of the suction holes. (For example, Japanese Patent Application Laid-Open No. 1983-1999)
No. 170488).

An example of the conventional refrigerant compressor mentioned above will be explained with reference to FIG. 6. In the figure, 1 is a cylinder having a cylindrical inner wall, and a rotor 2 is disposed inside. The rotor 2 has radial slits in which the vanes 3 slide. Both sides of the cylinder 10 are closed by a front plate 4 and a rear plate 6, and a rad cover 7 is fixed to the cylinder, which has a suction port 6 at the top.
A suction chamber 8 is formed. A first suction hole 9 is provided in the cylinder 1, and a second suction hole 10 is provided at the suction end point of the rear plate 6. A solenoid valve 12 is provided in the refrigerant gas flow path 11 leading from the suction chamber 8 to the second suction hole.
will be installed. The electromagnetic valve 12 includes a movable iron core 14 sliding within a sleeve 13, a piston 16 made of a non-magnetic material attached to the movable iron core, an iron core receiver 16, a permanent magnet 17, and a secondary coil. 18゛ and secondary coil 1
9, a bias spring 2o, an outer yoke 21, and a lower yoke 22. In addition, 23 is an intermediate plate, 2
4 is the rear case, 26 is the discharge port, 26 is the shaft,
27 is a clutch.

The operation of the refrigerant compressor configured as above will be described below. In the case of full-load operation that produces the maximum cooling capacity, a pulse current is applied to the primary coil of the solenoid valve 12,
The movable iron core 14 is attracted to the iron core receiver 16, and is held by the permanent magnet 17 after energization. At this time, the piston 15 attached to the movable iron core 14 separates from the valve seat 28 formed on the rear plate 5, and the refrigerant gas flow path 1
1, refrigerant gas is also supplied into the cylinder 1 from the second suction hole 1o. Therefore, sufficient refrigerant gas is supplied into the cylinder 1 through the first suction hole 9 and the second suction hole 10, and maximum cooling capacity is obtained.

Next, in the case of par) cr-do operation that controls the cooling capacity,
When the secondary coil 19 of the solenoid valve 12 is energized in pulses, a magnetic field is applied in a direction that demagnetizes the magnetic force of the permanent magnet 17, and the movable iron core 14 held by the permanent magnet 17 is moved by the spring force of the bias spring 20. The piston 15 is separated from the receiver 16 and comes into close contact with the valve seat 28. Therefore, flow path 1
1 is shut off, and refrigerant gas is not supplied from the second suction hole 1o, but is supplied into the cylinder 1 only from the first suction hole 9, and the cooling capacity is controlled.

Problems to be Solved by the Invention However, in the above configuration, when switching from part-load operation to full-load operation, a pressure difference occurs before and after the movable iron core 14 and piston 16 of the solenoid valve 12, and the suction force The movable iron core 14 cannot be attracted unless it is made large. This is because during part-load operation, refrigerant gas is supplied into the cylinder 1 only from the first suction hole 9.
The inside of the cylinder 1 is not filled with refrigerant gas, and the pressure is lower than the supply pressure. Therefore, the pressure in the flow path 11 that is blocked by the piston 16 is the supply pressure on the upstream side of the piston 16, and the average pressure in the cylinder 1 on the downstream side, which is lower than that on the upstream side.

Therefore, the force due to the pressure difference is applied to the upstream side of the movable iron core 14 and the piston 16, and the suction force of the movable iron core 14 increases. The broken line A in FIG. 4 indicates the power consumption which is the operating limit of the movable iron core 14 with respect to the differential pressure in the conventional example, and the power consumption increases as the differential pressure increases. Moreover, the broken line A in FIG. 5 indicates the power consumption which is the operating limit of the movable iron core 14 with respect to the rotational speed, and the higher the rotational speed, the greater the power consumption. This is because as the rotation speed increases, the time for which the refrigerant is supplied from the first suction hole 9 into the cylinder 1 becomes shorter, and the amount of refrigerant supplied decreases, so the average pressure inside the cylinder 1 decreases and the piston 15 This is because the differential pressure between the upstream side and the downstream side becomes large.

As described above, in the conventional configuration, a pressure difference occurs between the upstream side and the downstream side of the movable iron core 14 and the piston 15, and when this pressure difference becomes large, the electromagnetic valve required to attract the movable iron core 14 12 increases, the movable iron core 14 is not attracted, and switching from part-load operation to full-load operation may not be possible.

The present invention solves the above problems and provides a refrigerant that reduces the power consumption of the solenoid valve and improves the operational reliability of capacity control by eliminating the pressure difference between the movable iron core and the front and rear of the piston with a simple configuration. The company provides compressors.

Means for Solving the Problems In order to solve the above problems, the refrigerant compressor of the present invention includes a cylinder having a cylindrical inner wall, a rotor disposed within the cylinder, and a rotor formed radially within the rotor. a plurality of slits, a plurality of vanes that slide within the slits, a side plate that closes the cylinder from both sides, and two suction holes that supply refrigerant gas into the cylinder;
It is equipped with a solenoid valve that directly opens and closes a refrigerant gas flow path leading to one of the suction holes by activating a movable iron core to which a piston is attached by pulsed energization,
The piston and the movable iron core have a through hole in the center, and are formed in a shape such that the piston and the flow path are in line contact with each other.

Effects The effects of the above-described configuration of the present invention are as follows. That is, the movable iron core of the solenoid valve is attracted by pulsed energization and held by a permanent magnet. Further, when a pulse current is applied in a direction to demagnetize the permanent magnet, the movable iron core separates from the magnetic force of the permanent magnet. A piston is attached to this movable iron core, and it directly opens and closes a flow passage to one of two suction holes through which refrigerant gas is supplied into the cylinder. In this way, when the flow path is open, sufficient refrigerant gas is supplied into the cylinder from the two suction holes, resulting in full-load operation that produces the maximum cooling capacity.
When the flow path is closed, only one suction hole
Refrigerant gas will be supplied, resulting in part-load operation with controlled discharge capacity. During this part-load operation, the average pressure inside the cylinder decreases, and a pressure difference occurs in the flow passages on the upstream and downstream sides of the piston. , by making the pressure applied to the piston from the downstream flow path equal to the pressure applied to the upper end of the movable iron core, and by bringing the piston and flow path into line contact, the pressure outside the contact area of the piston is set to the pressure of the upstream flow path. Therefore, the pressure difference between the movable iron core and the piston is almost eliminated.

As a result, the movable iron core and piston are hardly affected by pressure differences during part-load operation, reducing the power consumption of the solenoid valve, which is the operating limit of the movable iron core, and increasing the operational reliability of capacity control. At the same time, miniaturization of solenoid valves,
Energy saving can be achieved.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 3. In FIGS. 1 and 2, 28 is a cylinder having a cylindrical inner wall, and a rotor 29 is disposed inside. The rotor 29 has a radial sill 30, in which vanes 31 slide. The cylinder 28 is closed on both sides by a front plate 32 and a rear plate 33. A rad cover 34 is provided with a suction port 36 to the cylinder, and a suction chamber 36 and a discharge chamber 37 are formed.

A first suction hole 38 is provided in the cylinder 28, and a second suction hole 39 is provided at the suction end point of the rear plate 33.
is provided. From the suction chamber 36 to the second suction hole 39
A valve seat 42 is formed between an upstream flow path 40 and a downstream flow path 41, which are flow paths for refrigerant gas, and a solenoid valve 43 is installed therein. The electromagnetic valve 43 includes a movable iron core 45 that slides within a sleeve 44, a piston 46 made of a non-magnetic material attached to the movable iron core 46, and an iron core receiver 4.
7, a permanent magnet 48, a secondary coil 49, a secondary coil 60, a bias spring 51, an outer yoke 62,
It is composed of a lower yoke 63.

A through hole 5 is formed in the center of the movable iron core 45 and the piston 46.
4, and a sealing member 66 is inserted between the movable iron core 45 and the sleeve 44.

Further, the surface of the piston 46 that contacts the valve seat 42 is formed at an acute angle, and is in line contact with the valve seat 42 .

In addition, 66 is an intermediate plate, 67 is a discharge hole, 68 is a discharge valve, 69 is a discharge valve holding plate, 60 is a rear case, 61 is a discharge boat, 62 is a shaft, and 63 is a clutch.

The operation of the refrigerant compressor configured as above will be explained. Figure 3 shows the operating state of the solenoid valve 43 that performs capacity control. Figure 3a shows the state during full-load operation that produces the maximum cooling capacity, and Figure 3 shows the state during part-load operation that performs capacity control. state.

First, in the case of full load operation, when the negative side coil 44 is energized in pulses, the movable iron core 46 is attracted to the iron core receiver 47, and this state is maintained by the permanent magnet 48. The piston 46 attached to the movable iron core 45 separates from the valve seat 42, and the upstream flow passage 4° and the downstream flow passage 41 are connected, and the refrigerant gas flows through the first suction hole 38. Air is supplied into the cylinder 28 from both of the second suction holes 39, providing maximum cooling capacity.

Next, when switching to vert road operation, when a pulse current is applied to the secondary coil 49 and a magnetic field is applied in a direction to demagnetize the magnetic force of the permanent magnet 48, the movable iron core 45 is moved by the spring force of the bias spring 61. It separates from the iron core receiver 4 and the piston 46 comes into contact with the valve seat. At this time, the upstream flow path 4
o and the downstream flow path 41 are cut off, and refrigerant gas is supplied into the cylinder 28 only from the first suction hole 38, and the second
The cooling capacity is reduced by the amount of refrigerant gas that is not supplied from the suction hole 39, and the capacity is controlled. During this part-time road driving,
Since the average pressure inside the cylinder 28 is lower than the supply pressure, for the upstream flow passage 4o which is approximately equal to the supply pressure,
The pressure inside the downstream flow passage 41 decreases, and a pressure difference occurs between the two flow passages. Since the valve seat 42 is formed in a shape that makes line contact with the valve seat 42, the forces applied to the movable iron core 45 and the piston 46 in the vertical direction are canceled out. Note that a sealing member 55 is inserted between the movable iron core 45 and the sleeve 44 to prevent leakage from the upstream flow path 4o.

Therefore, when switching from part-load operation to full-load operation, almost no force due to pressure difference acts on the movable iron core 46 and the piston 46, so the bias spring 6
1 spring force, sliding resistance of the seal member 65 and movable iron core 4
5 and the suction force that overcomes the weight of the piston.

The solid line in FIG. 4 indicates the power consumption that is the operating limit of the movable iron core 46 with respect to the differential pressure in this embodiment, and the influence of the differential pressure is negligible. It shows the power consumption that is the operating limit of the movable iron core 46 with respect to the rotation speed, and the increase in power consumption is slight.

As described above, according to this embodiment, the power consumption of the solenoid valve, which is the operating limit of the movable iron core, can be reduced by having a configuration that is not affected by the pressure difference between the movable iron core and the piston of the solenoid valve. In addition to increasing the operational reliability of capacity control, it is also useful for downsizing and energy saving of solenoid valves.

In this embodiment, full load operation is performed in a state where the movable iron core is attracted and held, but a similar configuration is also possible for vert load operation.

Effects of the Invention As described above, the present invention includes a cylinder having a cylindrical inner wall, a rotor disposed within the cylinder, a plurality of slits formed radially within the rotor, and a rotor that slides within the slit. a plurality of vanes that close the cylinder from both sides, two suction holes that supply refrigerant gas into the cylinder, and a flow of refrigerant gas that leads to one of the suction holes. It consists of a movable iron core that directly opens and closes the passage, a piston, a permanent magnet, a bias spring, and a solenoid valve consisting of a negative side and a secondary side coil. Activate it,
Since the capacity can be controlled, the configuration is simple, the refrigerant compressor can be made smaller, the reliability of the capacity control is increased, and energy savings are achieved, so the practical effects are extremely large.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a refrigerant compressor according to an embodiment of the present invention, Fig. 2 is a front sectional view of the refrigerant compressor, and Figs. 3 a and b are operation of a solenoid valve used in the refrigerant compressor. Explanatory drawings, Fig. 4 is a diagram showing the relationship between the power consumption of the solenoid valve and the differential pressure, Fig. 5 is a diagram showing the relationship between the power consumption of the solenoid valve and the rotation speed, and Fig. 6 is a diagram showing the relationship between the power consumption of the solenoid valve and the rotation speed.
The figure is a longitudinal sectional view of a conventional refrigerant compressor. 28... Cylinder, 29 River... Rotor, 31
...Vane, 38...First suction hole, 3
9...Second suction hole, 4o...Upstream flow passage, 41...Downstream flow passage, 42...
・Valve seat, 43...Solenoid valve, 44...Sleeve, 45...Movable iron core, 4e...
Piston, 48...Permanent magnet, 49...
・-Next coil, 6゜・・・Secondary coil, 61
......No (Iasuno (ne, 54......through hole. Name of agent: Patent attorney Toshi Nakao, male, and 1 other person 2T)
---1-1 cow 6-・-σ
0 stone hand 3-・Constant embroidery station Fig. 2 Fig. 3, t, 2 Fig. 4 Fig. 5 Rotation speed Upm) Fig. 6

Claims (1)

[Claims] a cylinder having a cylindrical inner wall; a rotor disposed within the cylinder; a plurality of slits formed radially within the rotor; a plurality of vanes sliding within the slits; A side plate that closes from the surface, two suction holes that supply refrigerant gas into the cylinder, and an electromagnetic valve that opens and closes a refrigerant gas flow path leading to one of the suction holes, and the electromagnetic The valve includes a primary coil that attracts the movable iron core in the sleeve, a permanent magnet that holds the attracted movable iron core, a secondary coil that demagnetizes the magnetic force of the permanent magnet, and a secondary coil that restores the movable iron core. The movable iron core and the piston have a through hole in the center, and the piston and the flow path are formed in a line contact shape. refrigerant compressor.