JP2001200789A - Vibration type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a vibration type compressor as well as preventing reduction of piston position detecting accuracy. SOLUTION: A fixing part 19a of a displacement detector 19 is disposed on the end part of the reverse compression chamber side of a cylinder 15, and a movable core part 19b is disposed on an outer peripheral part of a piston 16. Reduction of the position detecting accuracy caused by the influence of assembly accuracy can be prevented, and also the compressor can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating compressor used for a refrigeration cycle or the like.

[0002]

2. Description of the Related Art A conventional vibratory compressor is disclosed in
Japanese Unexamined Patent Publication (Kokai) No. 3247674 discloses an example. Hereinafter, the conventional vibrating compressor will be described with reference to the drawings.

FIG. 10 shows a conventional configuration. FIG. 10 is a longitudinal sectional view of a conventional vibrating compressor. In FIG. 7, 1 is a closed container, and 2 is a main body. The main body 2 includes a motor 3, a cylinder 4, a piston 5, a block 6, a cylinder head 7, an elastic element 8, and the like. The motor 3 includes a stator 3a formed of pure iron and a mover 3b formed of a coil, and a permanent magnet 3c is fixed to the stator 3a. The mover 3b is connected and fixed to the piston 5 via a mover connecting member 9. The piston 5 is supported by the cylinder 4 and the elastic element 8 so as to be slidable in the axial direction.

The elastic element 8 has an inner peripheral part fixed to the piston 5 and an outer peripheral part fixed to the block 6. Reference numeral 10 denotes a movable element including the piston 5, the mover 3b of the motor 3, the mover connecting member 9, and the like.
It is a fixed element composed of the stator 3a of the motor 3, the block 6, and the like. Reference numeral 12 denotes a compression chamber,
It is formed by a piston 5. Reference numeral 13 denotes a displacement detector, which includes a movable core 13a connected to the movable element 10 via a connecting member 14 in the axial direction of the piston 5, and a fixed part 13b attached to the fixed element and housing the movable core 13a therein. And a coil is formed in the fixed portion 13b.

Next, the mechanism of the vibrating compressor will be described. When an AC power generated by using an inverter circuit (not shown) is supplied to the mover 3b (coil) of the motor 3, the mover 3b (coil) is acted upon by the action of a magnetic field generated by the permanent magnet 3c due to the current supply. Generates a reciprocating force in the axial direction. By the force, the mover connecting member 9
The piston 5 connected to the mover 3b through the elastic member 8 deforms the elastic element 8 and efficiently reciprocates in the axial direction while utilizing the repulsive force of the elastic element 8.

[0006] The displacement detector 1 accompanying the reciprocation of the piston 5
The movable core portion 13a reciprocates in the fixed portion 13b, and a voltage corresponding to the position of the piston 5 is applied to the fixed portion 13b (coil).
, Whereby the position of the piston 5 can be known.

[0007] Refrigerant gas from a cooling system (not shown) is guided to a low-pressure chamber 7a of the cylinder head 7 via a suction pipe (not shown), and reaches a compression chamber 12 in the cylinder 4.
The refrigerant gas that has reached the compression chamber 12 is compressed by the reciprocating motion of the piston 5 described above. The compressed refrigerant gas is supplied to a discharge valve (not shown) provided in the cylinder head 7.
Once discharged into the high-pressure chamber 7b in the cylinder head 7 through the discharge pipe (not shown).

[0008]

However, in the above-described conventional configuration, the displacement detector 13 is connected to the movable element 10 in the axial direction of the piston 5 via the connecting member 14, so that the displacement detector 13 is affected by assembly accuracy. However, there is a disadvantage that the position detection accuracy may be easily reduced.

An object of the present invention is to solve the conventional problems, and an object of the present invention is to provide a vibrating compressor having high position detection accuracy without being affected by assembly accuracy.

[0010] The above-mentioned conventional configuration has a displacement detector 13.
Is connected to the movable element 10 in the axial direction of the piston 5 via the connecting member 14, there is a disadvantage that the overall shape of the compressor may increase in the axial direction of the piston 5.

Another object of the present invention is to provide a vibration-type compressor which can reduce the shape of the compressor as a whole, reduce leakage of refrigerant gas from a compression chamber, and have high efficiency.

Further, the above-mentioned conventional configuration is provided with the displacement detector 13.
There is a disadvantage that the fixing portion 13b may expand or contract due to the influence of heat transfer from the refrigerant gas in the closed vessel 1, and the position detection accuracy may be reduced.

Another object of the present invention is to provide a vibrating compressor capable of preventing a change in top clearance even when the temperature of a fixed portion of a displacement detector changes, thereby obtaining a stable refrigeration capacity.

Another object of the present invention is to provide a vibration type compressor in which a displacement detector can be easily assembled.

Further, the above-mentioned conventional configuration is provided with the displacement detector 13.
Have a temperature drift characteristic, the displacement detector 13
When the temperature changes, the output voltage changes and the top clearance also changes, so there is a drawback that the refrigerating capacity may decrease or the movable element 10 may collide with the fixed element 11.

Another object of the present invention is to maintain a small top clearance irrespective of the temperature of the displacement detector, thereby preventing a decrease in refrigeration capacity and preventing an excessive amplitude of the piston, thereby providing a highly reliable vibration type. It is to provide a compressor.

Further, in the above-described conventional configuration, when the external conditions such as the outside air temperature, the power supply voltage, and the load suddenly change and the top clearance sharply decreases, the movable element 10 and the fixed element 11
However, there was a drawback that there was a possibility of collision.

Another object of the present invention is to provide a highly reliable vibration compressor which reliably prevents an excessive amplitude of a piston even when external conditions change suddenly.

[0019]

SUMMARY OF THE INVENTION In order to achieve this object, the present invention provides a cylinder, a piston which is reciprocally slidable in the cylinder and forms a compression chamber in the cylinder space, a stator and a movable member. A motor composed of a child and
A fixed element constituted by the cylinder, the stator, and the like, a movable element constituted by the piston, the movable element, and the like, a part of which is fixedly held by the fixed element and a part of which is fixed or connected to the movable element Elastic element, and a displacement detector for detecting at least the top dead center position of the piston, the displacement detector is a fixed portion disposed at the end of the cylinder opposite the compression chamber, It is composed of a movable core portion arranged on the outer peripheral portion.

Thus, the displacement detector is built in the motor, so that it is possible to prevent a decrease in position detection accuracy due to the influence of assembly accuracy and to reduce the size of the compressor.

Further, according to the present invention, the outer diameter of the movable core portion of the displacement detector is smaller than the outer diameter of the sliding portion of the piston.

As a result, the size of the compressor can be reduced, and the sliding length between the cylinder and the piston can be increased, so that the leakage of refrigerant gas from the compression chamber can be reduced, and the efficiency can be improved by reducing the leakage loss. Can be planned.

Further, according to the present invention, the constituent material of the fixed portion of the displacement detector is a material having a linear expansion coefficient equal to or less than that of the cylinder material.

As a result, even if the temperature of the fixed portion rises, the fixed portion does not expand excessively, and the positional relationship between the movable core portion and the fixed portion can be kept constant. Capability can be prevented from lowering.

Further, according to the present invention, the movable core portion of the displacement detector is constituted by at least two divisions in the axial direction.

As a result, it is possible to improve the assemblability when attaching the movable core to the outer periphery of the movable element.

Further, the present invention comprises a cylinder, a piston reciprocally slidable in the cylinder, a motor comprising a stator and a mover, and the cylinder, the stator and the like. Fixed element, a movable element constituted by the piston, the mover, and the like, an elastic element partially fixed to the fixed element and partially fixed or connected to the movable element, and at least the piston The differential transformer detects a top dead center position, and the output voltage of the differential transformer is set to approximately 0 V at the top dead center position of the piston.

As a result, it is possible to prevent the differential transformer from being affected by the temperature drift, so that it is possible to reduce the top clearance by suppressing variations in the top clearance, to obtain a high refrigerating capacity, and to increase the piston amplitude. It is possible to prevent the collision between the movable element and the fixed element and the reduction in the reliability of the elastic element.

Further, the present invention is provided with an inverter circuit and inverter control means for stopping the supply of voltage to the motor or reducing the supply voltage when the output voltage of the differential transformer is inverted.

Thus, even if the amplitude of the piston increases due to a sudden change in external conditions such as the outside air temperature, the power supply voltage, and the load, the collision between the movable element and the fixed element is reliably prevented, and the reliability is improved. it can.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a cylinder, a piston which is reciprocally slidable in the cylinder and forms a compression chamber in the cylinder space, a stator and a movable member. And a fixed element formed by the cylinder and the stator, a movable element formed by the piston and the mover, and a part fixedly held by the fixed element. An elastic element fixed or connected to the movable element, and a displacement detector for detecting at least a top dead center position of the piston, wherein the displacement detector is provided at an end of the cylinder opposite the compression chamber. Fixed portion and a movable core portion disposed on the outer peripheral portion of the piston. Since the displacement detector is incorporated in the motor, a decrease in position detection accuracy is prevented. With wear, such an action can be made compact compressor.

According to a second aspect of the present invention, in the first aspect, the outer diameter of the movable core portion of the displacement detector is smaller than the outer diameter of the sliding portion of the piston. Since the core portion can also reciprocate in the cylinder, the compressor can be reduced in size, the sliding length between the cylinder and the piston can be increased, and leakage of refrigerant gas from the compression chamber can be reduced. Therefore, there is an effect that the efficiency can be improved by reducing the leakage loss.

According to a third aspect of the present invention, in the first aspect of the present invention, the material of the fixing portion of the displacement detector is made of a material having a linear expansion coefficient equal to or less than that of the cylinder material. Even if the temperature rises, the fixed part does not expand excessively, and the positional relationship between the movable core part and the fixed part can be kept constant, so that the top clearance can be prevented from increasing and the refrigeration capacity can be prevented from lowering. Has the effect of being able to.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the movable core of the displacement detector is divided into at least two parts in the axial direction. This has the effect that the assemblability at the time of attachment can be improved.

According to a fifth aspect of the present invention, there is provided a cylinder, and a piston disposed reciprocally slidably in the cylinder,
A motor constituted by a stator and a mover, a fixed element constituted by the cylinder and the stator, a movable element constituted by the piston and the mover, etc. An elastic element fixedly held and partly fixed or connected to the movable element, and a differential transformer for detecting at least a top dead center position of the piston, wherein an output voltage of the differential transformer is detected by the top dead center of the piston. It is approximately 0 V at the point position, so that the differential transformer can be prevented from being affected by the temperature drift, so that the top clearance can be kept small, a high refrigerating capacity can be obtained, and the amplitude of the piston can be increased. This has the effect of preventing a collision between the movable element and the fixed element and a reduction in the reliability of the elastic element.

According to a sixth aspect of the present invention, in addition to the fifth aspect of the present invention, when the output voltage of the inverter circuit and the differential transformer is inverted, the supply of the voltage to the motor is stopped or the supply voltage is reduced. It is provided with an inverter control means for lowering, and reliably prevents the collision between the movable element and the fixed element even if the amplitude of the piston increases due to sudden changes in external conditions such as outside temperature, power supply voltage, load, This has the effect of improving reliability.

[0037]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a vibrating compressor according to an embodiment of the present invention. The same components as those of the related art are denoted by the same reference numerals, and detailed description is omitted.

(Embodiment 1) FIG. 1 is a longitudinal sectional view of a main part of a vibrating compressor according to Embodiment 1 of the present invention.

In FIG. 1, reference numeral 15 denotes a cylinder,
6 is reciprocatingly arranged in the cylinder 15
A piston 17 forms the compression chamber 12 in the inner space, 17 is a fixed element constituted by the cylinder 15 and the stator 3a of the motor 3, and 18 is a piston 16 and the movable element 3
b. Reference numeral 19 denotes a displacement detector such as a differential transformer for detecting at least the top dead center position of the piston 16.
And a movable core 19b disposed on the outer periphery of the piston 16.

The operation of the vibrating compressor constructed as described above will be described below.

As the piston 16 reciprocates, the movable core 19b of the displacement detector 19 reciprocates in the fixed portion 19a.
A voltage corresponding to the position of the piston 16 is induced in the fixed portion 19a, whereby the position of the piston 16 can be known. Here, since the displacement detector 19 is incorporated in the motor 3, assembling is performed in comparison with a configuration in which the movable core 13a is connected to the movable element 10 via the connecting member 14 in the axial direction of the piston 5 as in the conventional example. A decrease in position detection accuracy due to the influence of the accuracy can be prevented, and the overall length of the compressor in the piston axial direction is shortened, so that the compressor can be downsized.

As described above, the vibratory compressor of this embodiment is
A motor 3 comprising a cylinder 15, a piston 16 which is reciprocally slidable in the cylinder 15 and forms a compression chamber 12 in a space inside the cylinder 15, a motor 3 comprising a stator 3 a and a mover 3 b, A fixed element 17 constituted by a child 3a and the like; a movable element 18 constituted by a piston 16 and a movable element 3b;
And a displacement detector 19 for detecting at least the top dead center position of the piston 16.
Reference numeral 9 denotes a fixed portion 19a provided at the end of the cylinder 15 on the side opposite to the compression chamber, and a movable core portion 19b provided on the outer peripheral portion of the piston 16.
Since it is configured to be incorporated in the inside, it is possible to prevent a decrease in position detection accuracy due to the influence of assembly accuracy, to shorten the overall length of the compressor in the axial direction of the compressor, and to reduce the size of the entire compressor. .

(Embodiment 2) FIG. 2 is a longitudinal sectional view of a main part of a vibrating compressor according to Embodiment 2 of the present invention.

In FIG. 2, reference numeral 20 denotes a displacement detector such as a differential transformer for detecting at least the top dead center position of the piston 16, and the displacement detector 20 is disposed at the end of the cylinder 15 on the side opposite to the compression chamber. It comprises a fixed portion 19a and a movable core portion 20a provided on the outer periphery of the piston 16, and the outer diameter of the movable core portion 20a is smaller than the outer diameter of the sliding portion of the piston 16.

The operation of the vibrating compressor constructed as described above will be described below.

As the piston 16 reciprocates, the movable core 20a of the displacement detector 20 reciprocates in the fixed portion 19a,
A voltage corresponding to the position of the piston 16 is induced in the fixed portion 19a, whereby the position of the piston 16 can be known. Here, since the outer diameter of the movable core portion 20a provided on the outer peripheral portion of the movable element 18 is smaller than the outer diameter of the piston 16, the movable core portion 20a is
5, the cylinder 15 and the piston 1
6 can be extended, so that the compression chamber 12
Leakage of refrigerant gas from the fuel cell can be reduced. Therefore, leakage loss can be reduced and efficiency can be improved.

If the sliding length between the cylinder 15 and the piston 16 is not increased, the overall length of the compressor in the axial direction of the compressor can be shortened accordingly, so that the compressor can be further downsized.

As described above, the vibratory compressor of this embodiment is
The outer diameter of the movable core portion 20a of the displacement detector 20 is
6 and the movable core 20a can reciprocate in the cylinder 15 together with the piston 16, so that the sliding length between the cylinder 15 and the piston 16 can be increased, and the compression chamber Since the leakage of the refrigerant gas from the refrigerant gas 12 can be reduced, the efficiency can be improved by reducing the leakage loss.

When the sliding length between the cylinder 15 and the piston 16 is not increased, the overall length of the compressor in the axial direction of the compressor can be shortened accordingly, so that the compressor can be further downsized. .

(Embodiment 3) FIG. 3 is a longitudinal sectional view of a main part of a vibrating compressor according to Embodiment 3 of the present invention.

In FIG. 3, reference numeral 21 denotes a displacement detector such as a differential transformer for detecting at least the top dead center position of the piston 16, and reference numeral 21a denotes a fixed portion of the displacement detector 21. It is made of a material that is equal to or less than the coefficient of linear expansion.

The operation of the vibrating compressor constructed as described above will be described below.

With the reciprocating motion of the piston 21, the movable core portion 24b of the displacement detector 25 reciprocates in the fixed portion 25a.
A voltage corresponding to the position of the piston 21 is induced in the fixed portion 25a, whereby the position of the piston 21 can be known.

However, during operation of the compressor, the compression chamber 1
The temperature of the cylinder 15 rises due to heat transfer from the refrigerant gas compressed to a high pressure and a high temperature in the cylinder 2, and accordingly, the fixed portion 21 a of the displacement detector 21 disposed at the end of the cylinder 15 on the side opposite to the compression chambers The temperature also rises due to heat conduction from the cylinder 15. In addition, the temperature of the refrigerant gas in the closed container is controlled by the motor 3.
The temperature rises due to heat generation and heat generation in the mechanical part, and the temperature of the fixed part 21a further rises due to heat transfer from the refrigerant gas. At this time, if the linear expansion coefficient of the material forming the fixed portion 21a is larger than the linear expansion coefficient of the material of the cylinder 15, the fixed portion 21a expands toward the bottom dead center by δ due to a temperature rise. As a result, the relative position of the fixed portion 21a with respect to the position of the movable core portion 19b moves toward the bottom dead center of the piston 16 by δ, and the absolute value of the output voltage from the fixed portion 21a at the top dead center position decreases. I do. Accordingly, the top clearance at the top dead center position of the piston 16 increases by δ,
The refrigeration capacity is reduced.

On the other hand, when the linear expansion coefficient of the material forming the fixed portion 21a is larger than the linear expansion coefficient of the material of the cylinder 15 at a low outside air temperature, the fixed portion 21a contracts toward the top dead center of the piston 16 and The relative position of the fixed portion 21a to the portion 19b moves to the top dead center side, and the absolute value of the output voltage from the fixed portion 21a at the top dead center position increases. When the compressor is started in a state where the fixed portion 21a is contracted in this way, a collision between the movable element 10 and the fixed element 11 due to a decrease in the top clearance occurs.

Therefore, if the constituent material of the fixing portion 21a is a material having a coefficient of linear expansion equal to or less than that of the material of the cylinder 15, even if the temperature of the fixing portion 21a rises or falls, the fixing portion 21a
Does not excessively expand or contract, and can maintain a constant positional relationship between the movable core portion 19b and the fixed portion 21a. Therefore, it is possible to prevent an increase in the top clearance, prevent a decrease in refrigeration capacity, and prevent the top clearance. The collision between the movable element 10 and the fixed element 11 due to the decrease in the distance can be prevented, and reliability can be improved.

As described above, the vibratory compressor of this embodiment is
The constituent material of the fixing portion 21a of the displacement detector 21 is the cylinder 1
Since the material having a coefficient of linear expansion equal to or less than that of the five materials was used, the fixed portion 21a did not expand or contract excessively even if the temperature of the fixed portion 21a changed, and the positional relationship between the movable core portion 19b and the fixed portion 21a was kept constant. To prevent an increase in top clearance, prevent a decrease in refrigeration capacity, and improve reliability by preventing collision between movable and fixed elements due to a decrease in top clearance. Can be.

(Embodiment 4) FIG. 4 is a longitudinal sectional view of a main part of a vibrating compressor according to Embodiment 4 of the present invention, and FIG. 5 is an external view of a movable core portion of a displacement detector of the embodiment. It is.

In FIGS. 4 and 5, reference numeral 22 denotes a piston having a recess 22a in the axial direction, and reference numeral 23 denotes a movable element constituted by a piston, a movable element 3b of a motor, and the like. Reference numeral 24 denotes a displacement detector such as a differential transformer for detecting at least the top dead center position of the piston 22, and 24a is divided into at least two parts in the axial direction,
The movable core portion is disposed in the movable core portion. The movable core 24
The outer diameter of “a” is smaller than the outer diameter of the sliding portion of the piston 22.

The operation of the vibrating compressor configured as described above will be described below.

To increase the rigidity of the movable element 23 by increasing the shaft diameter of the piston 22, it is necessary to provide a recess 22a in the piston 22 in order to dispose the movable core 24a of the displacement detector 24. Here, if the movable core portion 24a is configured to be divided in the axial direction, the movable core portion 24a can be disposed on the piston 22 without forming the piston 22 as a separate body. The assemblability can be improved without the need.

As described above, the vibratory compressor of this embodiment is
Since the movable core portion 24a of the displacement detector 24 is configured to be divided into at least two in the axial direction, when the movable core portion 24a is arranged on the outer peripheral portion of the piston 22, the assemblability is improved regardless of the shape of the piston 22. can do.

(Embodiment 5) FIG. 6 is a longitudinal sectional view of a vibrating compressor according to Embodiment 5 of the present invention, and FIG. 7 is a temperature characteristic diagram of the differential transformer of the embodiment.

In FIG. 6, reference numeral 25 denotes a differential transformer for detecting at least the top dead center of the piston 5, via the connecting member 14 so that the output voltage becomes approximately 0 V at the top dead center position of the piston 5. It is connected to the movable element 10.

The operation of the vibrating compressor constructed as described above will be described below with reference to the temperature characteristic diagram of the differential transformer shown in FIG.

The differential transformer 25 has such a characteristic that the output voltage changes with a temperature change despite the fact that the position of the piston 5 does not change. The change width increases as the output voltage value departs from 0V. Become.

However, since the output voltage hardly changes even when the temperature changes near 0 V, the output voltage of the differential transformer 25 is set to be near 0 V at the top dead center position of the piston 5. By assembling, the output voltage can be kept constant even when the temperature of the differential transformer 25 changes, so that the compressor can be operated with a constant top clearance. Therefore, a decrease in refrigeration capacity due to an increase in the top clearance can be prevented, and a predetermined top clearance can be maintained, so that the collision between the movable element 10 and the fixed element 11 due to the decrease in the top clearance and the elastic element 8 It is possible to prevent a decrease in reliability.

As described above, the vibratory compressor of this embodiment is
A cylinder 4, a piston 5 arranged reciprocally slidable in the cylinder 4, a motor 3 composed of a stator 3a and a mover 3b, and a stationary element 11 composed of the cylinder 4, the stator 3a, and the like. And a movable element 10 composed of a piston 5 and a mover 3b, and a part of the fixed element 1
An elastic element 8 fixed and held at 1 and partially fixed or connected to the movable element 10 and a differential transformer 25 for detecting at least the top dead center position of the piston 5, and the output voltage of the differential transformer 25 is Since the voltage is set to approximately 0 V at the top dead center of the piston 5, the influence of the temperature drift of the differential transformer 25 can be prevented. Therefore, since the top clearance can be kept constant, it is possible to prevent a decrease in the refrigerating capacity due to an increase in the top clearance, and it is possible to always keep the predetermined top clearance. It is possible to prevent the collision between the fixed element 11 and the fixed element 11 and the reduction in the reliability of the elastic element 8.

Although the output voltage of the differential transformer 25 at the bottom dead center side of the piston 5 is positive in this embodiment, the same effect can be obtained even if the output voltage at the bottom dead center side is negative. No.

(Embodiment 6) FIG. 8 is an electric circuit diagram of a vibrating compressor according to Embodiment 6 of the present invention, and FIG. 9 is a timing chart showing the operation of the embodiment.

In FIG. 8, reference numeral 26 denotes an inverter circuit for supplying a voltage to the motor 3, and reference numeral 27 denotes inverter control means for turning on / off the output voltage of the inverter circuit.

The operation of the vibrating compressor configured as described above will be described below with reference to the timing chart of FIG.

The differential transformer 25 is arranged so that its output voltage is close to 0 V at the top dead center position of the piston 5. However, during operation of the compressor, external differentials such as outside air temperature, power supply voltage, load, etc. When the output voltage of the differential transformer 25 sharply increases with a sudden change in the condition, and the amplitude of the piston 5 increases, the top clearance becomes smaller than a predetermined value.
The output voltage of the differential transformer 25 is inverted. At the moment when the positive / negative reversal occurs, the inverter control circuit 27 stops the voltage supply from the inverter circuit 26 to the motor 3, so that the compressor is stopped and the movable element 1 is stopped.
0 and the fixed element 11 can be reliably prevented from colliding.

As described above, the vibratory compressor of this embodiment is
Since the inverter circuit 26 and the inverter control means 27 for stopping the supply voltage to the motor 3 when the output voltage of the differential transformer 25 is inverted, the outside temperature,
Even if the top clearance decreases due to abrupt changes in external conditions such as a power supply voltage and a load, collision between the movable element 10 and the fixed element 11 can be reliably prevented, and reliability can be improved.

Although the output voltage of the differential transformer 25 at the bottom dead center side of the piston 5 is positive in this embodiment, the same effect can be obtained even when the output voltage at the bottom dead center side is negative. No.

Further, in this embodiment, the differential transformer 2
5 when the output voltage of the inverter 5 is inverted.
To stop the voltage supply to the motor 3 from the
It goes without saying that the same effect can be obtained even if the supply voltage is reduced.

[0077]

As described above, according to the first aspect of the present invention, there is provided a cylinder, a piston which is reciprocally slidable in the cylinder and forms a compression chamber in the cylinder space, a stator and a movable member. And a fixed element formed by the cylinder and the stator, a movable element formed by the piston and the mover, and a part fixedly held by the fixed element. An elastic element fixed or connected to the movable element, and a displacement detector for detecting at least a top dead center position of the piston, wherein the displacement detector is provided at an end of the cylinder opposite the compression chamber. And a movable core disposed on the outer periphery of the piston, and the displacement detector is incorporated in the motor. It decreases with can be prevented, the overall length of the piston-axis direction of the compressor can be shortened, it is possible to reduce the size of the whole compressor.

The invention described in claim 2 is the first invention.
In addition to the invention described in the above, by making the outer diameter of the movable core portion of the displacement detector smaller than the outer diameter of the piston, the movable core portion together with the piston can reciprocate in the cylinder, so that the distance between the cylinder and the piston Since the sliding length can be lengthened and the leakage of the refrigerant gas from the compression chamber can be reduced, the efficiency can be improved by reducing the leakage loss.

When the sliding length between the cylinder and the piston is not increased, the overall length of the compressor in the axial direction of the compressor can be shortened by that amount, so that the compressor can be further downsized.

The invention described in claim 3 is the first invention.
In addition to the invention described in the above, the material of the fixed part of the displacement detector is made of a material equal to or less than the linear expansion coefficient of the cylinder material, so that the fixed part expands or contracts excessively even if the temperature of the fixed part changes. Without reducing the top clearance, it is possible to prevent the refrigeration capacity from lowering because the positional relationship between the movable core part and the fixed part can be kept constant. Element collision can be prevented and reliability can be improved.

The invention described in claim 4 is the first invention.
In addition to the invention described in the above, the movable core portion of the displacement detector is configured to be divided into at least two in the axial direction, so that when the movable core portion is arranged on the outer peripheral portion of the piston, the assemblability is improved regardless of the piston shape. can do.

According to a fifth aspect of the present invention, there is provided a motor comprising a cylinder, a piston disposed reciprocally slidably in the cylinder, a stator and a movable element, A fixed element constituted by a child or the like, a movable element constituted by the piston or the movable element, and an elastic element partially fixed to and held by the fixed element and partially fixed or connected to the movable element. A differential transformer for detecting at least the top dead center position of the piston, and by setting the output voltage of the differential transformer to approximately 0 V at the top dead center position of the piston, the temperature drift of the differential transformer is reduced. Influence can be prevented, and the top clearance can be kept constant. Can be kept in the top clearance, it can be prevented the occurrence of lowering the reliability of the collision and the elastic element of the movable element and the fixed element due to the reduction of the top clearance.

The invention described in claim 6 is the same as that in claim 5
In addition to the invention described in the above, the inverter circuit and the inverter control means for stopping the supply of the voltage to the motor or reducing the supply voltage when the output voltage of the differential transformer is inverted are provided during the operation of the compressor. Even if the top clearance decreases below a predetermined value due to a sudden change in external conditions such as the outside air temperature, the power supply voltage, and the load, the collision between the movable element and the fixed element can be reliably prevented, and the reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of a vibration compressor according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part of a vibration compressor according to a second embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a main part of a vibration type compressor according to a third embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a main part of a vibration type compressor according to a fourth embodiment of the present invention.

FIG. 5 is an external view of a movable core unit according to the embodiment.

FIG. 6 is a longitudinal sectional view of Embodiment 5 of the vibration compressor according to the present invention.

FIG. 7 is a temperature characteristic diagram of the differential transformer according to the embodiment.

FIG. 8 is an electric circuit diagram of Embodiment 6 of the vibrating compressor according to the present invention.

FIG. 9 is a timing chart showing the operation of the embodiment.

FIG. 10 is a longitudinal sectional view of a conventional vibratory compressor.

[Explanation of symbols]

 Reference Signs List 3 motor 3a stator 3b mover 4 cylinder 5 piston 8 elastic element 10 movable element 11 fixed element 12 compression chamber 15 cylinder 16 piston 17 fixed element 18 movable element 19 displacement detector 19a fixed part 19b movable core part 20 displacement detector 20a Movable core unit 21 Displacement detector 21a Fixed unit 24 Displacement detector 24a Movable core unit 25 Differential transformer 26 Inverter circuit 27 Inverter control means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junta Kawabata 4-5-2-5 Takaida Hondori, Higashi-Osaka City, Osaka Inside Matsushita Refrigerating Machinery Co., Ltd. (72) Inventor Masanori Kobayashi 4-chome, Takaida Hondo, Higashi-Osaka City, Osaka Prefecture No. 2 Matsushita Refrigerator Co., Ltd. (72) Inventor Koji Inagaki 4-5-2-5 Takashita Hondori, Higashi Osaka City, Osaka Prefecture (72) Inventor Takanori Ishida Takaida Hondori, Higashi Osaka City, Osaka Prefecture 4-2-5 Matsushita Refrigerator Co., Ltd. (72) Inventor Makoto Katayama 4-2-5 Takaida Hondori, Higashi-Osaka City, Osaka Prefecture Matsushita Refrigerator Co., Ltd. F-term (reference) 3H045 AA03 AA12 AA27 BA41 CA21 DA07 EA34 3H076 AA02 BB21 BB38 BB40 BB50 CC06 CC98

Claims (6)

[Claims] 1. A motor comprising a cylinder, a piston which is reciprocally slidable in the cylinder and forms a compression chamber in the cylinder space, a motor comprising a stator and a mover, the cylinder and the stationary A fixed element constituted by a child or the like, a movable element constituted by the piston or the movable element, and an elastic element partially fixed or held to the fixed element and partially fixed or connected to the movable element. ,
A displacement detector for detecting at least a top dead center position of the piston, wherein the displacement detector is disposed at a fixed portion disposed at an end of the cylinder opposite to the compression chamber, and disposed at an outer peripheral portion of the piston. A vibrating compressor composed of a movable core part. 2. The vibration type compressor according to claim 1, wherein the outer diameter of the movable core portion of the displacement detector is smaller than the outer diameter of the sliding portion of the piston. 3. The vibratory compressor according to claim 1, wherein the constituent material of the fixed portion of the displacement detector is a material having a linear expansion coefficient equal to or less than that of a cylinder material. 4. The vibrating compressor according to claim 1, wherein the movable core portion of the displacement detector is configured to be divided into at least two in the axial direction. 5. A cylinder, a piston arranged reciprocally slidably in the cylinder, a motor constituted by a stator and a mover, and a stationary element constituted by the cylinder, the stator and the like. A movable element constituted by the piston, the mover, and the like; an elastic element partially fixed and held by the fixed element and partially fixed or connected to the movable element; and at least a top dead center position of the piston. And a differential transformer for detecting the output of the piston, wherein the output voltage of the differential transformer is substantially 0 V at the top dead center of the piston. 6. An inverter circuit for supplying a voltage to a motor, and inverter control means for stopping the supply of voltage to the motor or reducing the supply voltage when the output voltage of the differential transformer is inverted. The vibratory compressor as described.