JP2003148340A - Sealed motor-driven compressor and refrigerating device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealed motor-driven compressor capable of reducing a required refrigerant quantity by using a refrigerant mainly composed of hydrocarbon having a small warming factor. SOLUTION: This inverter-driven reciprocating sealed motor-driven compressor is driven by a plurality of operating frequencies including a rotating speed less than a commercial power frequency. A motor-driven element is composed of a rotor embedded with a permanent magnet, and an intensively wound stator having a teeth part in a core, the teeth part intensively wound with a coil to reduce the space volume in a sealed vessel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor used in electric refrigerators and vending machines.

[0002]

2. Description of the Related Art In recent years, demands for the global environment have been increasing more and more, and movements such as energy saving and regulation of gas with high greenhouse effect have been accelerated.

The conventional technique is disclosed in JP-A-11-10793.
There is one disclosed in Japanese Patent No.

Hereinafter, the above-mentioned conventional hermetic electric compressor will be described with reference to the drawings. In the following description, the relationship between the upper and lower sides is based on the state in which the hermetic electric compressor is installed in a regular posture.

FIG. 5 is a cross-sectional view of a conventional hermetic electric compressor, in which 1 is a hermetic container for storing refrigerating machine oil 2 inside. 5
Is an electric element provided in the closed container 1, and has a distributed winding stator 3 and a rotor 4 incorporating a permanent magnet (not shown).
Consists of. Reference numeral 6 denotes a compression element located under the electric element 5, which is driven by the electric element 5 and is both closed.
Housed in.

Further, this hermetic electric compressor is R13 which is a typical HFC refrigerant having an ozone depletion coefficient of zero.
It is designed to compress 4a.

The details of the compression element 6 will be described below.

Reference numeral 10 denotes a crankshaft, which is a main shaft portion 11 and a main shaft portion 1 in which the rotor 4 of the electric element 5 is press-fitted and fixed.
The eccentric portion 12 is formed so as to be eccentric with respect to 1. 20
Is a cylinder block having a substantially cylindrical compression chamber 22 and a bearing portion 23 for supporting the main shaft portion 11.

A piston 30 is fitted in the compression chamber 22,
The eccentric portion 12 is connected by a connecting means 31. A suction tube 39 is fixed to the closed container 1 and is connected to the low pressure side (not shown) of the refrigeration cycle to guide a refrigerant gas (not shown) into the closed container 1. 40
Forms a sound deadening space 42 with a suction muffler.

An inverter device 60 is connected to the distributed winding stator 3. 61 is a control circuit for controlling the inverter device 60, 62 is a commercial power source, and the control circuit 61,
And to the inverter device 61.

Next, details of the electric element 5 will be described.

FIG. 6 is a plan view of a conventional stator, showing a winding state of a distributed winding stator 3 which has been most commonly used since ancient times. FIG. 7 is an external view thereof.

Reference numeral 50 denotes a stator core, which is formed by laminating an annular core 54 having slots 52 formed at predetermined intervals, and a plurality of slots 52 are provided between the slots by an inserter winding method. This is a well-known stator in which a winding wire 56 in which wires are bundled is inserted. Reference numeral 58 is a crossover wire extending from the winding wire 56 and extending between the respective slots to form a coil end having a height H1.

Next, a series of operations in the above configuration will be described.

Electric power supplied from the commercial power supply 62 is supplied to the electric element 5 via the control circuit 61 and the inverter 60, and the rotor 4 of the electric element 5 is rotated at an arbitrary rotation speed. The rotor 4 rotates the crankshaft 10, and the eccentric movement of the eccentric portion 12 causes the piston 30 to move through the connecting means 31.
When the piston 30 is driven, the piston 30 reciprocates in the compression chamber 22, and the refrigerant gas introduced into the closed container 1 through the suction tube 39 is sucked from the suction muffler 40 and continuously compressed in the compression chamber 22. It

[0016]

This hermetic electric compressor of the prior art is designed to compress R134a, which is a typical HFC refrigerant having an ozone depletion potential of zero, but includes R134a. HFC-based refrigerants have a high global warming potential, and it has been decided that they will eventually be regulated.

In place of this, hydrocarbon refrigerants that have already been put to practical use in Europe and have a zero ozone depletion potential and a small global warming potential, specifically R600a and R290, are considered to be the most promising alternatives in Japan. Has been. On the other hand, such a hydrocarbon-based refrigerant is more strongly combustible than the refrigerant R134a, and it is preferable that the total amount of refrigerant enclosed in the refrigeration cycle is small.

However, in the hermetic electric compressor of the prior art, since the connecting wire extending from the winding 56 in which a plurality of wires are bundled forms the coil end across each slot,
Inevitably, the size of H1 becomes large, and as a result, the total height of the closed container that stores this becomes high.

This means that the space volume of the closed container becomes large without repairing, that is, the enclosed amount of the refrigerant filling the space increases, which hinders the reduction of the above-mentioned total enclosed amount of the refrigerant. ing.

The present invention solves these problems by providing a hermetic electric compressor that uses a refrigerant mainly containing hydrocarbons and can reduce the required amount of refrigerant, and also reduces the total amount of refrigerant enclosed. An object of the present invention is to provide a refrigeration device that can be used.

[0021]

According to a first aspect of the present invention, a refrigerant containing a hydrocarbon refrigerant as a main component is used, and the refrigerant is driven at a plurality of operating frequencies including rotation speeds lower than the commercial power frequency. An hermetic electric compressor driven by an inverter, wherein the electric element comprises a rotor having a permanent magnet embedded therein, and a concentrated winding stator having teeth and concentrated windings around the teeth. Thus, the space inside the closed container of the compressor can be reduced, and the total enclosed amount of the refrigerant can be reduced.

According to a second aspect of the present invention, there is provided a refrigeration apparatus including a compressor, a condenser, a drier, an expander, and an evaporator, and the hermetic electric compressor according to the first aspect. It has the effect of reducing the total amount of refrigerant enclosed.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a hermetic electric compressor according to the present invention will be described below with reference to the drawings. The same components as those in the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

(Embodiment 1) FIG. 1 is a sectional view of a hermetic electric compressor according to a first embodiment of the present invention, in which 101 is a hermetic container in which refrigerating machine oil 102 is stored. Reference numeral 105 denotes an electric element, which includes a concentrated winding stator 103 and a rotor 104 having a permanent magnet (not shown) built therein. Reference numeral 106 denotes a compression element, which is driven by the electric element 105 and is housed in the closed container 101 together.

The hermetic electric compressor is designed to compress a hydrocarbon refrigerant having a zero ozone depletion potential and a small global warming potential, specifically, a refrigerant mainly containing R600a or R290. There is.

Details of the compression element 6 will be described below.

Reference numeral 110 is a crankshaft, which is the rotor 10.
4 has a main shaft portion 111 into which press-fitting is fixed, and an eccentric portion 112 formed eccentrically with respect to the main shaft portion 111. Reference numeral 120 denotes a cylinder block, which has a substantially cylindrical compression chamber 122 and a bearing portion 123 that pivotally supports the main shaft portion 111.

A piston 130 is fitted in the compression chamber 122 and is connected to the eccentric portion 112 by a connecting means 131. 139 is a suction tube, which is a closed container 1.
01 and is connected to the low-pressure side (not shown) of the refrigeration cycle to store the refrigerant gas (not shown) in the closed container 1.
Lead into 01. A suction muffler 140 forms a sound deadening space 142.

An inverter device 60 is connected to the concentrated winding stator 103. Reference numeral 61 is a control circuit for controlling the inverter device 60, and 62 is a commercial power source for the control circuit 6
1 and the inverter device 61.

Next, details of the electric element 105 will be described.

FIG. 2 is a plan view of the stator according to the first embodiment of the present invention, showing a winding state of the concentrated winding stator 103. FIG. 3 is an external view thereof. Reference numeral 150 denotes a stator core, which is formed by stacking annular cores 154 having teeth portions 152 formed at predetermined intervals, and windings 156 are wound around the teeth portions 152. 15
Reference numeral 8 is a connecting wire which normally connects between the windings by one wire, and forms a coil end portion 159 having a height H2 which is much lower than the conventional corend height H1.

Next, a series of operations in the above configuration will be described.

Electric power supplied from the commercial power source 62 is supplied to the electric element 105 via the control circuit 61 and the inverter 60, and causes the rotor 104 of the electric element 105 to rotate at an arbitrary rotational speed. The rotor 104 is the crankshaft 110.
And the eccentric movement of the eccentric part 112 causes the connecting means 131 to rotate.
By driving the piston 130 via the
0 reciprocates in the compression chamber 122, and the refrigerant gas introduced into the closed container 101 through the suction tube 139 is sucked from the suction muffler 140,
It is continuously compressed in 22.

The concentrated winding stator 1 of the electric element 105
Reference numeral 03 forms a coil end portion having a height H2 which is much lower than the conventional corend height H1.

As a result, the total height of the hermetically-sealed container for containing the same can be kept extremely low, which means that the space volume of the hermetically-sealed container becomes small without repairing, that is, the refrigerant filling the space is The reduction in the amount of the enclosed gas makes it possible to reduce the required total amount of the enclosed refrigerant.

Generally, the power consumption of a compressor becomes smaller as the operating frequency becomes lower, and on the other hand, the refrigerating capacity corresponding to the load is also required at the same time. A plurality of output frequencies are arbitrarily set up to a level exceeding the frequency of.

When operating at a low frequency, which is commonly used under these operating conditions, the amount of work is small and the amount of heat generated is small. As a result, the temperature of the closed container 101 is low, and the circulating amount of the refrigerant is small. As a result, the evaporation pressure rises,
Due to these synergistic effects, the refrigerant density in the space of the closed container 101 is relatively high, and as a result, the closed container 101
The effect of reducing the required total enclosed amount of the refrigerant obtained by reducing the space volume of is much larger than that of the hermetic electric compressor operated at a constant rotation speed at the power supply frequency.

In the present embodiment, the reciprocating type compressor having a low pressure inside the closed container is taken as an example. However, even if the rotary type compressor has a high pressure inside the closed container, the space volume of the closed container is small. It goes without saying that a large reduction effect of the required total enclosed amount of the refrigerant can be obtained.

(Second Embodiment) FIG. 4 is a block diagram of a refrigerating apparatus according to the present invention. In FIG. 4, 170 is a compressor, 1
80 is a condenser, 185 is a dryer, 187 is an expander, 18
Reference numeral 9 denotes an evaporator, each of which is fluidly connected by piping by welding such as brazing. The compressor 170 is the one described in claim 1 of the present invention.

In the above structure, if the brazing seal connecting the components of the refrigeration system is incomplete, the refrigerant will leak little by little from the seal.
Since the space volume of the closed container of 0 is small, the amount of the refrigerant filled in the space is reduced, so that the total amount of the refrigerant enclosed in the refrigeration system can be reduced.

Therefore, even if the refrigerant leaks, the total amount thereof is small, so that a refrigerating apparatus with higher safety can be obtained.

[0042]

As described above, the invention described in claim 1 is an inverter drive which uses a refrigerant containing a hydrocarbon refrigerant as a main component and is driven at a plurality of operating frequencies including a rotation speed lower than the commercial power supply frequency. Is a closed hermetic electric compressor,
The electric element is composed of a rotor having a permanent magnet embedded therein, a toothed portion, and a concentrated winding stator in which windings are concentratedly wound around the toothed portion, thereby using a refrigerant mainly containing hydrocarbon, and The required amount of refrigerant can be reduced.

According to a second aspect of the present invention, the hermetic electric compressor according to the first aspect is used in a refrigerating apparatus including a compressor, a condenser, a drier, an expander, and an evaporator. However, since a refrigerant mainly containing hydrocarbons is used and the total amount of the refrigerant enclosed can be reduced, a safer refrigeration system can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a hermetic electric compressor according to an embodiment of the present invention.

FIG. 2 is a plan view of the stator according to the first embodiment of the present invention.

FIG. 3 is an external view of a stator according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram of a refrigerating apparatus according to a second embodiment of the present invention.

FIG. 5 is a sectional view of a conventional hermetic electric compressor.

FIG. 6 is a plan view of a conventional stator.

FIG. 7 is an external view of a conventional stator.

[Explanation of symbols]

60 inverter device 61 Control circuit 101 airtight container 102 Refrigerator oil 103 Concentrated winding stator 104 rotor 105 Electric element 106 compression element 152 Teeth 154 core 156 winding 170 compressor 180 condenser 185 dryer 187 expander 189 evaporator

Claims (2)

[Claims] 1. A refrigerating machine oil, a compression element, and
An inverter-driven hermetically-sealed electric motor that accommodates an electric element that drives the compression element and that uses a refrigerant containing a hydrocarbon refrigerant as a main component and that is driven at a plurality of operating frequencies including a rotation speed lower than the commercial power supply frequency A hermetic compressor characterized in that the electric element comprises a rotor having a permanent magnet embedded therein, and a concentrated winding stator having a tooth portion in a core and windings concentratedly wound around the tooth portion in the previous period. Type electric compressor. 2. A refrigerating apparatus comprising a compressor, a condenser, a drier, an expander, and an evaporator, wherein the hermetic electric compressor according to claim 1 is used as the compressor.