JP5004535B2 - Turbine unit for air cycle refrigeration cooling - Google Patents

Description

  The present invention relates to a turbine unit for an air cycle refrigeration cooling system in which air is used as a refrigerant and is used for a refrigeration warehouse, a low-temperature room of zero degrees or less, and air conditioning.

  The use of air as a refrigerant is preferable in terms of environmental protection and safety compared to the case of using chlorofluorocarbon or ammonia gas, but is insufficient in terms of characteristics as energy efficiency. However, when used in a facility that can directly blow in air, such as a refrigerated warehouse, the total cost can be reduced to the same level as existing systems by taking measures such as omitting the internal fan and defrost. there is a possibility. At present, the use of chlorofluorocarbon as a refrigerant is already restricted from the environmental viewpoint, and it is desired to avoid using other refrigerant gas as much as possible. Therefore, an air cycle refrigeration cooling system that uses air as a refrigerant has been proposed for the above-described applications (for example, Patent Document 1 and Non-Patent Document 1).

Further, it is stated that the theoretical efficiency of air cooling is equal to or higher than that of chlorofluorocarbon or ammonia gas in a deep coal region of −30 ° C. to −60 ° C. (Non-patent Document 1). However, it is also stated that obtaining the theoretical efficiency of the air cooling is not possible until there is an optimally designed peripheral device. The peripheral device is a compressor, an expansion turbine, or the like.
As the compressor and the expansion turbine, a turbine unit in which a compressor impeller and an expansion turbine impeller are attached to a common main shaft is used (Patent Document 1, Non-Patent Document 1).

In addition, as a turbine compressor which processes process gas, a turbine impeller is attached to one end of the main shaft, a compressor impeller is attached to the other end, and the main shaft is supported by a journal and a thrust bearing that is controlled by an electromagnet current. A compressor has been proposed (Patent Document 2).
In addition, although it is a proposal for a gas turbine engine, in order to avoid the thrust load acting on the rolling bearing for supporting the main shaft from shortening the bearing life, the thrust load acting on the rolling bearing should be reduced by the thrust magnetic bearing. Has been proposed (Patent Document 3).
Japanese Patent No. 2623202 Japanese Patent Application Laid-Open No. 7-91760 JP-A-8-261237 Magazine, Nikkei Mechanical, “Cooling the Air with Air”, published November 13, 1995, no 467, pp. 46-52

As described above, as the air cycle refrigeration cooling system, in order to obtain the theoretical efficiency of air cooling that is highly efficient in the deep coal region, an optimally designed compressor and expansion turbine are required.
As the compressor and the expansion turbine, a turbine unit in which the compressor wheel and the expansion turbine wheel are attached to a common main shaft as described above is used. In this turbine unit, the compressor impeller can be driven by the power generated by the expansion turbine, thereby improving the efficiency of the air cycle refrigerator.

However, in order to obtain practical efficiency, it is necessary to keep the gap between each impeller and the housing minute. The fluctuation of the gap hinders stable high-speed rotation and causes a decrease in efficiency.
In addition, a thrust force acts on the main shaft by the air acting on the compressor impeller and the turbine impeller, and a thrust load is applied to the bearing that supports the main shaft. The rotation speed of the main shaft of the turbine unit in the turbine unit for air cycle refrigeration cooling is 80,000 to 100,000 rotations per minute, which is very high compared to a bearing for general use. For this reason, the thrust load as described above causes a decrease in long-term durability and life of the bearing supporting the main shaft, and decreases the reliability of the turbine unit for air cycle refrigeration cooling. Unless the problem of long-term durability of such a bearing is solved, it is difficult to put the air cycle refrigeration cooling turbine unit into practical use, and hence the air cycle refrigeration cooling system into practical use. However, the techniques disclosed in Patent Document 1 and Non-Patent Document 2 have not yet been solved with respect to a decrease in the long-term durability of the bearing against a thrust load under high-speed rotation.

In the case where the main shaft is supported by a journal bearing made of a magnetic bearing and a thrust bearing, such as the magnetic bearing type turbine compressor of Patent Document 2, the journal bearing does not have a restriction function in the axial direction. For this reason, if there is an unstable factor in controlling the thrust bearing, it is difficult to perform stable high-speed rotation while maintaining a minute gap between the impeller and the housing. In the case of a magnetic bearing, there is also a problem of contact when the power is stopped.
Further, in an air cycle refrigeration cooling turbine unit in which a main shaft is rotatably supported by a bearing, and a thrust force applied to the main shaft is supported partly or entirely by an electromagnet by an output of a sensor that detects a thrust force acting on the main shaft. If the accuracy of detecting the thrust force acting on the main shaft is low, there is a problem that the thrust force on the bearing cannot be effectively reduced and the long-term durability of the bearing cannot be ensured.

  An object of the present invention is an air cycle refrigeration cooling that can achieve stable high-speed rotation while maintaining a minute clearance of an impeller, and can improve long-term durability, long life, and reliability of a bearing that supports a main shaft at low cost. A turbine unit for a vehicle is provided.

An air cycle refrigeration cooling turbine unit of the present invention is an air cooling turbine unit having a compressor and an expansion turbine, wherein the compressor impeller of the compressor and the turbine impeller of the expansion turbine are attached to a common main shaft, The compressor impeller is driven by the power generated in the turbine impeller, or a motor rotor is attached to a common main shaft to which the compressor impeller and the turbine impeller are attached, and the main shaft is rotated by the motor, whereby the compressor impeller is rotated. Which rotates the car,
The main shaft is rotatably supported by a rolling bearing, and the thrust force applied to the main shaft is supported partly or entirely by an electromagnet according to the output of a sensor that detects the thrust force acting on the main shaft. A turbine unit,
The sensor is arranged on the stationary side in the vicinity of the rolling bearing , and the sensor has a sensor element whose characteristics are changed by the pressing force, and sensor elements that can electrically detect the characteristic change are arranged around the spindle axis in the circumferential direction. and is from the outputs of the plurality of sensor elements to detect the thrust forces, Ru der that is interposed between the spindle housing for supporting the outer ring and the outer ring of the rolling bearing. The sensor detects a thrust force by detecting the permeability of a plurality of magnetostrictive materials or giant magnetostrictive materials arranged in a circumferential direction around the spindle axis. Before SL rolling bearing, which has a holding function of the axial-direction position between the inner and outer rings, such as deep groove ball bearings or the like are preferable. The rolling bearing may be an angular ball bearing.

The turbine unit for air cycle refrigeration cooling having this configuration includes, for example, compression by pre-compression means, cooling by a heat exchanger, compression by a compressor of the turbine unit, cooling by another heat exchanger for the incoming air, the turbine unit This is applied to an air cycle refrigeration cooling system that sequentially performs adiabatic expansion by an expansion turbine. In this case, the air used as the cooling medium is compressed by the compressor to increase the temperature so that the heat exchanger can efficiently exchange heat even with a medium having a relatively high temperature. It is cooled by a heat exchanger, led to an expansion turbine, and used to cool and discharge to a target temperature, for example, a very low temperature of about -30 ° C to 60 ° C by adiabatic expansion.
The turbine unit in this case has a compressor impeller and a turbine impeller of the expansion turbine attached to a common main shaft, and drives the compressor impeller by the power generated by the turbine impeller, so a power source is unnecessary. Cooling can be efficiently performed with a compact configuration.

  In addition to the above, the air cycle refrigeration cooling turbine unit of the present invention may be motor driven. For example, cooling by a heat exchanger, compression by a compressor of a turbine unit, cooling by another heat exchanger, adiabatic expansion by an expansion turbine of the turbine unit are sequentially performed on the inflow air, and the turbine unit is Compressor impeller of this type and turbine impeller of said expansion turbine and motor rotor are mounted on a common main shaft, and the main shaft is rotated by a magnetic force from a motor stator opposed to the motor rotor, thereby driving the compressor impeller and air cycle refrigeration cooling It may be applied to the system. When the main shaft is driven by providing a motor, it is not necessary to provide pre-compression means such as a blower before the compressor.

In order to ensure the efficiency of compression and expansion of this type of turbine unit, it is necessary to keep the gap between each impeller and the housing minute. In the air cycle refrigeration cooling system, ensuring this efficiency is important. On the other hand, in the air cycle refrigeration cooling turbine unit of the present invention, since the main shaft of the impeller is supported by the rolling bearing, the position of the main shaft is regulated to some extent by the restriction function of the axial position of the rolling bearing. The minute gap between the car and the housing can be kept constant.
However, a thrust force is applied to the main shaft of the turbine unit due to air pressure acting on each impeller. Further, in a turbine unit used in an air cooling system, the rotation speed is very high, for example, about 80,000 to 100,000 rotations per minute. For this reason, when the thrust force acts on a rolling bearing that rotatably supports the main shaft, the long-term durability of the main shaft decreases.

  In the present invention, since the thrust force is supported by the electromagnet, it is possible to reduce the thrust force acting on the rolling bearing for supporting the main shaft while suppressing an increase in torque without contact. In this case, since the sensor for detecting the thrust force acting on the main shaft by the air in the compressor and the expansion turbine and the controller for controlling the bearing force by the electromagnet according to the output of the sensor are provided, the rolling bearing is provided. It can be used in an optimum state with respect to the thrust force according to the bearing specifications. Therefore, stable high-speed rotation of the main shaft can be obtained while maintaining an appropriate clearance between the impellers, and the long-term durability and life of the rolling bearing can be improved. Since the long-term durability of the rolling bearing for supporting the main shaft is improved, the reliability of the entire air cycle refrigeration cooling turbine unit and, as a whole, the air cycle refrigeration cooling system is improved. As described above, stable high-speed rotation, long-term durability, and reliability of the main shaft bearing of the turbine unit, which is a bottleneck of the air cooling system, are improved, so that the air cycle refrigeration cooling system can be put to practical use.

  The rolling bearing may be arranged in the vicinity of the compressor wheel and the turbine wheel in the spindle housing. In this case, since the main shaft is supported at both ends, even more stable high-speed rotation is possible.

In the sensor, sensor elements whose characteristics change due to the pressing force and in which the characteristic change can be electrically detected are arranged in a circumferential direction around the spindle axis, and the thrust force is obtained from outputs of the plurality of sensor elements. It is to detect. This sensor is interposed between the outer ring of the rolling bearing and the spindle housing that supports the outer ring.
By arranging a plurality of sensor elements in the circumferential direction, it is possible to detect a thrust force acting between the outer ring of the rolling bearing and the spindle housing without causing an inclination. Further, by using a plurality of sensor elements, it is possible to average and detect forces acting on a plurality of locations in the circumferential direction.

  The plurality of sensor elements may be interposed between two ring-shaped members through which the main shaft passes. By interposing a sensor element between two ring-shaped members, a plurality of sensor elements can be handled as an integrated sensor, and assemblability is good.

More specifically, the sensor detects a thrust force by detecting the permeability of a plurality of magnetostrictive materials or super magnetostrictive materials arranged in a circumferential direction around the spindle axis. Also good. The plurality of magnetostrictive materials or giant magnetostrictive materials may be sandwiched between two yoke members made of a soft magnetic material. A second yoke member made of a soft material that is slightly shorter than the magnetostrictive material or the giant magnetostrictive material may be disposed between the two yoke members.
When a magnetostrictive material or a giant magnetostrictive material is used as the sensor element, the pressing force can be detected with high accuracy. Further, when the second yoke member is used, the magnetic resistance of the magnetic path is reduced, and the sensitivity of the sensor is improved. By making the length of the second yoke member slightly shorter than the magnetostrictive material or the giant magnetostrictive material, all of the detected thrust force acts on the magnetostrictive material or the giant magnetostrictive material, so that the detection of the pressing force is accurate. Can do well.

Further, permanent magnets magnetized in the thickness direction are provided in close contact with the end face of the magnetostrictive material or giant magnetostrictive material, and the magnetostrictive material or giant magnetostrictive material and the permanent magnet are made of two soft materials. It may be sandwiched between the yoke members. Also in this case, a second yoke member made of a soft material that is slightly shorter than the length in which the magnetostrictive material or super magnetostrictive material and the permanent magnet are overlapped is disposed between the two yoke members. You may do it.
When a permanent magnet is used, a bias magnetic field can be applied, and a portion having a large change in permeability of the magnetostrictive material or the giant magnetostrictive material can be selected and used for detection, and the detection sensitivity can be improved. By making the length of the second yoke member slightly shorter than the length of the magnetostrictive material or giant magnetostrictive material and the permanent magnet overlapped, all of the detected thrust forces act on the magnetostrictive material or giant magnetostrictive material. Therefore, the pressing force can be detected with high accuracy.

In the case of a sensor that detects a thrust force by detecting the permeability of the plurality of magnetostrictive materials or giant magnetostrictive materials, the sensor includes a sensor coil disposed around the magnetostrictive material or the giant magnetostrictive material, and the permeability May be detected by measuring the inductance of the sensor coil. In this case, a plurality of sensor coils may be provided, and the plurality of sensor coils may be connected in series to average the outputs of the sensor coils. In this case, the sensor coil and the magnetostrictive material or the giant magnetostrictive material may be an even number, and the currents flowing in the adjacent sensor coils may be in opposite directions.
When it is configured to detect by measuring the inductance of the sensor coil, a change in magnetic permeability can be detected with high accuracy. Further, the thrust force can be detected with high accuracy by providing a plurality of the sensor coils and averaging these outputs. Furthermore, by connecting a plurality of sensor coils in series, an inductance equivalent to the sum of the inductances of each sensor coil is connected between both ends of all the connected sensor coils. By detecting, it means that the inductance of each sensor coil is averaged, and it has an advantage that the averaging process can be easily performed. Furthermore, the magnetostrictive material or the giant magnetostrictive material is an even number, and the currents flowing through the adjacent sensor coils are in opposite directions so that a substantially common magnetic flux can be passed through the magnetostrictive material or the giant magnetostrictive material. In addition, since the inductance characteristics of the sensor coils can be made the same, detection can be performed with high accuracy.

In the case of a sensor that detects a thrust force by detecting the permeability of the plurality of magnetostrictive materials or giant magnetostrictive materials, the sensor uses resonance between the inductance of the sensor coil and a separate capacitor, and The inductance change may be measured from a change in resonance frequency that changes with a change in inductance.
If the inductance change is measured from the change in resonance frequency, the change in permeability can be detected with high accuracy.

  In the case of a sensor that detects a thrust force by detecting the permeability of the plurality of magnetostrictive materials or giant magnetostrictive materials, the sensor inputs a carrier wave having a constant frequency and a constant frequency to one end of the sensor coil. The inductance change may be measured from the voltage amplitude at the other end of the sensor coil, which changes due to the change in inductance, using the resonance between the inductance of the sensor coil and a separate capacitor. Even in this configuration, a change in magnetic permeability can be detected with high accuracy.

  In the case of a sensor that detects a thrust force by detecting the permeability of the plurality of magnetostrictive materials or giant magnetostrictive materials, the sensor arranges an excitation coil around the magnetostrictive material or the giant magnetostrictive material in addition to the sensor coil. The thrust force may be measured by passing an excitation current of a constant current through the excitation coil at a constant frequency and detecting the current excited in the sensor coil. In this configuration, by controlling the current flowing through the exciting coil, the magnetic permeability change point of the magnetostrictive material or super magnetostrictive material with respect to the load change can be set to the optimum one, and the change in magnetic permeability can be detected accurately. Can do.

  In the case of a sensor that detects a thrust force by detecting the permeability of the plurality of magnetostrictive materials or giant magnetostrictive materials, the sensor uses a Hall sensor to change the permeability of the magnetostrictive material or the giant magnetostrictive material. The thrust force may be measured by detecting the accompanying magnetic flux density. The Hall sensor connects the DC power supply from the outside and outputs the magnetic flux density of the environment in an analog manner, so it can be measured easily and inexpensively.

In the sensor of each configuration described above, a temperature sensor is arranged around the sensor coil or the magnetostrictive material or the giant magnetostrictive material, and the inductance measurement result or the magnetic permeability measurement result is corrected by the output of the temperature sensor. May be provided.
By performing temperature correction, accurate detection can be performed.

In the present invention, the sensor may be disposed in the vicinity of the rolling bearing. When the sensor is arranged in the vicinity of the rolling bearing, the thrust force acting on the rolling bearing in question can be directly measured, the measurement accuracy is good, and the thrust force can be precisely controlled.
Therefore, stable high-speed rotation of the main shaft can be obtained while maintaining an appropriate clearance between the impellers, and the long-term durability and life of the rolling bearing can be improved. Since the long-term durability of the rolling bearing for supporting the main shaft is improved, the reliability of the entire air cycle refrigeration cooling turbine unit and, as a whole, the air cycle refrigeration cooling system is improved. As described above, stable high-speed rotation, long-term durability, and reliability of the main shaft bearing of the turbine unit, which is a bottleneck of the air cycle refrigeration cooling system, are improved, and thus the air cycle refrigeration cooling system can be put to practical use.

In the turbine unit for air cycle refrigeration cooling according to the present invention, the sensor is interposed directly or via another member between the outer ring of the rolling bearing and the spindle housing that supports the outer ring. There may be.
By interposing the sensor between the outer ring of the rolling bearing and the spindle housing, the thrust force of the main shaft acting on the rolling bearing can be accurately measured with a simple configuration.

In this case, a bearing housing in which the outer ring of the rolling bearing is fixedly fitted is fitted into an inner diameter hole provided in the spindle housing so as to be movable in the axial direction, and the sensor is connected to the width surface of the bearing housing and the width surface of the bearing housing. You may interpose between a spindle housing or the member fixed to this spindle housing.
In this way, by making the bearing housing movable and arranging the sensor between the bearing housing and the spindle housing, the wide width surface of the bearing housing can be used for the arrangement of the sensor, and the radial thickness of the outer ring is thin. However, a relatively large sensor can be arranged to improve measurement sensitivity and accuracy.

  The sensor may be preloaded by a first spring element. Sensors that measure force by interposing between members generally cannot detect negative force. However, if preload is applied, either the forward or reverse can be detected by detecting the deviation from the preload amount. Even the thrust force in the direction can be detected.

The preload by the first spring element may be greater than an average thrust force acting on the main shaft by the air in the compressor and the expansion turbine.
By providing a preload that is equal to or greater than the average thrust force, a sufficient range of detectable force can be obtained when detecting a thrust force in either the forward or reverse direction based on the preload amount.
Note that the preload by the first spring element may be about the average thrust force.

In the air cycle refrigeration cooling turbine unit of the present invention, a plurality of the rolling bearings are provided, the sensor is disposed in the vicinity of one of the rolling bearings, and the other rolling bearing moves in the axial direction with respect to the spindle housing. It can be installed and elastically supported by the second spring element.
Since the other rolling bearing is elastically supported by the second spring element, an appropriate preload can be applied to the bearing. In addition, the axial position of the main shaft can be maintained with high accuracy, and the thrust force can be detected with high accuracy by the sensor.

  The second spring element is provided between the outer ring of the other rolling bearing and the spindle housing, or between the member fixing the outer ring of the other rolling bearing and the spindle housing, or the inner ring of the rolling bearing and the It is interposed between the main shaft. Even if it interposes in any of these places, the 2nd spring element can be installed with simple composition.

When the first spring element and the second spring element are provided, the second spring element has a spring constant smaller than that of the first spring element.
When the spring constant of the second spring element is larger than that of the first spring element, an excessive preload acts on both bearings when an excessive thrust force is applied to the main shaft. By keeping the spring constant of the second spring element small, it is possible to avoid this excessive preload acting on other bearings, and to obtain a stable rotational performance, while detecting the thrust force in both forward and reverse directions on the sensor. Preload can be applied.

In the present invention, a plurality of flange-shaped thrust plates made of a ferromagnetic material may be provided on the main shaft, and the electromagnets may be installed on a spindle housing provided with the bearings so as to face the width surfaces on both sides of each flange.
In the turbine unit, when the thrust force due to air pressure is large, the diameter of the thrust plate should be increased to increase the force of the electromagnet. However, at high speed rotation, there is a risk of being destroyed by centrifugal force, and there is a limit to increasing the diameter of the thrust plate. When a plurality of thrust plates are used, the supporting force against the thrust force can be increased without causing the problem of destruction due to centrifugal force.

  When a plurality of thrust plates are provided, the electromagnet may be divided into a plurality arranged in the circumferential direction. Since the electromagnet is divided, it can be easily assembled even if it has a plurality of thrust plates.

  The number of poles and the size of each of the electromagnets divided into a plurality and the number of turns of the built-in coil may be the same. By making the number of poles, size, and number of turns the same, an even electromagnetic force can be applied to the entire circumference, and each divided electromagnet has the same configuration, so that productivity and assembly are possible. Can be improved.

An air cycle refrigeration cooling turbine unit of the present invention is an air cooling turbine unit having a compressor and an expansion turbine, wherein the compressor impeller of the compressor and the turbine impeller of the expansion turbine are attached to a common main shaft, The compressor impeller is driven by the power generated in the turbine impeller, or a motor rotor is attached to a common main shaft to which the compressor impeller and the turbine impeller are attached, and the main shaft is rotated by the motor, whereby the compressor impeller is rotated. An air that rotates a vehicle, supports the main shaft rotatably by a rolling bearing, and supports part or all of the thrust force applied to the main shaft by an electromagnet by the output of a sensor that detects the thrust force acting on the main shaft. Turbine unit for cycle refrigeration cooling A is, wherein the sensor is arranged on the stationary side in the vicinity of the rolling bearing, circumferential said sensor characteristics change its characteristics changed by the pressing force is electrically detectable sensor elements around a spindle axis The thrust force is detected from the outputs of the plurality of sensor elements. The sensor is interposed between an outer ring of the rolling bearing and a spindle housing that supports the outer ring. Thrust force is detected by detecting the permeability of a plurality of magnetostrictive materials or super magnetostrictive materials arranged side by side in the circumferential direction around the spindle axis, and the plurality of magnetostrictive materials or super magnetostrictive materials are A permanent magnet that is sandwiched between two yoke members made of a soft magnetic material or magnetized in the thickness direction is provided in close contact with the end face of the magnetostrictive material or giant magnetostrictive material. And Luo magnetostrictive material or super magnetostrictive material and the permanent magnet, because sandwiched between two yoke members made of a soft material, stable high-speed rotation was is obtained while maintaining a small gap of impeller, the bearing supporting the main shaft Long-term durability, long life, and reliability can be improved.

That describes a first embodiment of the present invention in conjunction with FIGS. A specific configuration example of the sensor will be described later. FIG. 1 shows the overall configuration of an air cycle refrigeration cooling system. This air cooling system is a system that directly cools air in a space 10 to be cooled, such as a freezer, as a refrigerant, and has an air circulation path 1 extending from an air intake port 1a to a discharge port 1b respectively opened in the space to be cooled 10 Have. In this air circulation path 1, pre-compression means 2, first heat exchanger 3, dehumidifier 4, compressor 6 of air cycle refrigeration cooling turbine unit 5, second heat exchanger 8, intermediate heat exchanger 9, And the expansion turbine 7 of the said turbine unit 5 is provided in order. The intermediate heat exchanger 9 exchanges heat between the inflow air in the vicinity of the intake port 1a in the same air circulation path 1 and the air whose temperature has been raised by the subsequent compression, and is in the vicinity of the intake port 1a. Air passes through the heat exchanger 9a.

  The pre-compression means 2 comprises a blower or the like and is driven by a motor 2a. The first heat exchanger 3 and the second heat exchanger 8 have heat exchangers 3a and 8a for circulating a cooling medium, respectively, and a cooling medium such as water and an air circulation path in the heat exchangers 3a and 8a. Heat exchange with 1 air. Each of the heat exchangers 3 a and 8 a is connected to the cooling tower 11 by piping, and the cooling medium whose temperature is increased by heat exchange is cooled by the cooling tower 11.

  This air cycle refrigeration cooling system is a system that keeps the space to be cooled 10 at about 0 ° C. to −60 ° C., and is 1 atmosphere at about 0 ° C. to −60 ° C. from the space to be cooled 10 to the inlet 1a of the air circulation path 1. Inflow of air. Note that the numerical values of temperature and atmospheric pressure shown below are examples that serve as a guide. The air that has flowed into the intake port 1a is used by the intermediate heat exchanger 9 to cool the downstream air in the air circulation path 1 and is heated to 30 ° C. The heated air remains at 1 atm, but is compressed to 1.4 atm by the pre-compression means 2, and the temperature is raised to 70 ° C. by the compression. Since the 1st heat exchanger 3 should just cool the air of 70 degreeC which raised temperature, even if it is cold water about normal temperature, it can cool efficiently and it cools to 40 degreeC. The dehumidifier 4 prevents the moisture in the air in the air circulation path 1 from freezing due to cooling below the freezing point in the subsequent stage and causing clogging of the air circulation path 1 and galling of the expansion turbine 7. Dehumidify the air.

The air at 40 ° C. and 1.4 atm after dehumidification is compressed to 1.8 atm by the compressor 6 of the turbine unit 5, and the second heat exchanger 8 is heated to about 70 ° C. by this compression. To 40 ° C. The 40 ° C. air is cooled to −20 ° C. by the −30 ° C. air in the intermediate heat exchanger 9. The atmospheric pressure is maintained at 1.8 atmospheric pressure discharged from the compressor 6.
The air cooled to −20 ° C. by the intermediate heat exchanger 9 is adiabatically expanded by the expansion turbine 7 of the turbine unit 5, cooled to −55 ° C., and discharged from the outlet 1 b to the cooled space 10. This air cycle refrigeration cooling system performs such a refrigeration cycle.

  FIG. 2 shows a specific example of the turbine unit 5 for air cycle refrigeration cooling. The turbine unit 5 includes a compressor 6 and an expansion turbine 7. A compressor impeller 6 a of the compressor 6 and a turbine impeller 7 a of the expansion turbine 7 are respectively attached to both ends of the main shaft 13. Further, the compressor impeller 6a is driven by the power generated in the turbine impeller 7a, and no other drive source is provided.

  For example, as shown in the example of FIG. 26 described later, the compressor impeller 6 a of the compressor 6, the turbine impeller 7 a of the expansion turbine 7, and the motor rotor 92 are attached to the common main shaft 13, and the main shaft 13 is attached by the driving force of the motor 90. It may be driven. When the motor 90 is provided to drive the main shaft 13, it is not necessary to provide the pre-compression means 2 (FIG. 1) such as a blower before the compressor 6.

The compressor 6 has a housing 6b that opposes the compressor impeller 6a with a minute gap d1, and compresses air sucked in the axial direction from the suction port 6c in the center by the compressor impeller 6a, Discharge from the outlet (not shown) as shown by arrow 6d.
The expansion turbine 7 has a housing 7b that opposes the turbine impeller 7a with a minute gap d2, and aspirates and expands the air sucked from the outer peripheral portion as indicated by an arrow 7c by the turbine impeller 7a. Is discharged in the axial direction from the discharge port 7d.

  In the turbine unit 5, the main shaft 13 is supported by a plurality of bearings 15 and 16 in the radial direction, and the thrust force applied to the main shaft 13 is supported by an electromagnet 17. The turbine unit 5 includes a sensor 18 that detects a thrust force acting on the main shaft 13 by the air in the compressor 6 and the expansion turbine 7, and a controller 19 that controls the bearing force by the electromagnet 17 in accordance with the output of the sensor 18. have. The electromagnet 17 is installed in the spindle housing 14 so as to face the both surfaces of a flange-like thrust plate 13a made of a ferromagnetic material provided at the center of the main shaft 13 without contact.

  The bearings 15 and 16 for supporting the main shaft 13 are rolling bearings and have a function of regulating the axial position, and for example, deep groove ball bearings are used. In the case of a deep groove ball bearing, it has a thrust support function in both directions, and has the effect of returning the axial position of the inner and outer rings to the neutral position. These two bearings 15 and 16 are arranged in the vicinity of the compressor impeller 6a and the turbine impeller 7a in the spindle housing 14, respectively.

The main shaft 13 is a stepped shaft having a large-diameter portion 13b at the center and small-diameter portions 13c at both ends. The bearings 15 and 16 on both sides have their inner rings 15a and 16a fitted into the small diameter portion 13c in a press-fit state, and one of the width surfaces engages with a stepped surface between the large diameter portion 13b and the small diameter portion 13c.
The portions of the spindle housing 14 closer to the impellers 6a and 7a than the bearings 15 and 16 on both sides are formed with an inner diameter surface close to the main shaft 13, and non-contact seals 21 and 22 are formed on the inner diameter surface. Yes. The non-contact seals 21 and 22 are labyrinth seals in which a plurality of circumferential grooves are arranged in the axial direction on the inner diameter surface of the spindle housing 14.

  The sensor 18 is provided on the stationary side in the vicinity of the bearing 16 on the turbine impeller 7a side, that is, on the spindle housing 14 side. The outer ring 16 b of the bearing 16 provided with the sensor 18 in the vicinity thereof is fitted in the bearing housing 23 in a fixed state. The bearing housing 23 has an inner flange 23a that is formed in a ring shape and engages with the width surface of the outer ring 16b of the bearing 16 at one end, and is movable in the axial direction in an inner diameter hole 24 provided in the spindle housing 14a. It is mated. The inner collar 23a is provided at the center side end in the axial direction.

  The sensor 18 is interposed between the width surface of the bearing housing 23 on the inner flange 23 a side and one electromagnet 17 which is a member fixed to the spindle housing 14. The sensor 18 is applied with a preload by the first spring element 25. The first spring element 25 is housed in a housing recess provided in the spindle housing 14 to urge the outer ring 16b of the bearing 16 in the axial direction, and the sensor 16 is moved through the outer ring 16b and the bearing housing 23. Preload. The first spring element 25 is composed of, for example, coil springs provided at a plurality of locations in the circumferential direction around the main shaft 13.

  The preload by the first spring element 25 is to enable the sensor 18 that detects the thrust force by the pressing force to detect the movement of the main shaft 13 in any axial direction. The magnitude is greater than the average thrust force acting on the main shaft 13 in a normal operating state.

  The bearing 15 on the non-arrangement side of the sensor 18 is installed so as to be movable in the axial direction with respect to the spindle housing 14 and is elastically supported by a second spring element 26. In this example, the outer ring 15 b of the bearing 15 is fitted to the inner diameter surface of the spindle housing 14 so as to be movable in the axial direction, and the second spring element 26 is interposed between the outer ring 15 b and the spindle housing 14. . The second spring element 26 biases the outer ring 15b so as to face the step surface of the main shaft 13 with which the width surface of the inner ring 15a is engaged, and applies a preload to the bearing 15. The second spring elements 26 include coil springs and the like provided at a plurality of locations in the circumferential direction around the main shaft 13, and are accommodated in accommodation recesses provided in the spindle housing 14. The second spring element 26 has a smaller spring constant than the first spring element 25.

  In the air cycle refrigeration cooling system, the turbine unit 5 having this configuration is compressed by the compressor 5 to increase the temperature so that the air serving as a cooling medium can be efficiently heat exchanged by the heat exchangers 8 and 9 (FIG. 1). The air cooled by the heat exchangers 8 and 9 is used by the expansion turbine 7 to be cooled and discharged by adiabatic expansion to a target temperature, for example, a very low temperature of about −30 ° C. to −60 ° C.

In this turbine unit 5, the compressor impeller 6a and the turbine impeller 7a are attached to a common main shaft 13, and the compressor impeller 6a is driven by the power generated in the turbine impeller 7a, so that no power source is required. Cooling can be efficiently performed with a compact configuration.
In order to secure the efficiency of compression and expansion of the turbine unit 5, it is necessary to keep the gaps d1 and d2 between the impellers 6a and 7a and the housings 6b and 7b minute. In the air cycle refrigeration cooling system, ensuring this efficiency is important. On the other hand, since the main shaft 13 is supported by the rolling bearings 15 and 16, the axial position of the main shaft 13 is regulated to some extent by the restriction function of the axial position of the rolling bearing, and the impellers 6a and 7a The minute gaps d1 and d2 between the housings 6b and 7b can be kept constant.

However, a thrust force is applied to the main shaft 13 of the turbine unit 5 by the pressure of air acting on the impellers 6a and 7a. In addition, the turbine unit 5 used in the air cycle refrigeration cooling system rotates at a very high speed of, for example, about 80,000 to 100,000 rotations per minute. Therefore, when the thrust force acts on the rolling bearings 15 and 16 that rotatably support the main shaft 13, the long-term durability of the bearings 15 and 16 decreases.
In this embodiment, since the thrust force is supported by the electromagnet 17, the thrust force acting on the rolling bearings 15 and 16 for supporting the main shaft 13 can be reduced while suppressing an increase in torque without contact. In this case, a sensor 18 for detecting a thrust force acting on the main shaft 13 by the air in the compressor 6 and the expansion turbine 7 and a controller 19 for controlling the bearing force by the electromagnet 17 according to the output of the sensor 18 are provided. Therefore, the rolling bearings 15 and 16 can be used in an optimum state with respect to the thrust force according to the bearing specifications.
In particular, since the sensor 18 is disposed in the vicinity of the bearing 16, the thrust force acting on the bearing 16 in question can be directly measured, the measurement accuracy is good, and the thrust force can be precisely controlled. .

  Therefore, stable high-speed rotation of the main shaft 13 can be obtained while maintaining appropriate gaps d1 and d2 between the impellers 6a and 7a, and the long-term durability and life of the bearings 15 and 16 can be improved. Since the long-term durability of the bearings 15 and 16 is improved, the reliability of the entire air cycle refrigeration cooling turbine unit 5 and, as a whole, the air cycle refrigeration cooling system is improved. As described above, stable high-speed rotation, long-term durability, and reliability of the main shaft bearings 15 and 16 of the turbine unit 5 that are the bottleneck of the air cycle refrigeration cooling system are improved. It becomes possible.

  The bearings 15 and 16 are disposed in the vicinity of the compressor impeller 6a and in the vicinity of the turbine impeller 7a, and the main shaft 13 is supported at both ends, so that more stable high-speed rotation is possible. Further, since the bearing 15 formed of a rolling bearing is elastically supported by the second spring element 26 and applies an appropriate preload, the axial position of the main shaft 13 is stabilized, and the minute gap d1 between the impellers 6a and 7a. , D2 are more reliably maintained, and more stable high-speed rotation can be obtained.

  Since non-contact seals 21 and 22 are provided between the main shaft 13 and the spindle housing 14 on the end side of the bearings 15 and 16, air passes through the bearings 15 and 16 and the like with the compressor 6. Leakage between the expansion turbines 7 is prevented. Since there is a large pressure difference between the inside of the compressor 6 and the inside of the expansion turbine 7, the inside of each bearing 15, 16 and the surface on which the inner and outer rings 15 a, 16 a of each bearing 15, 16 are fitted to the main shaft 13 and the spindle housing 14. Air leaks are about to occur. Such air leakage causes the efficiency of the compressor 6 and the expansion turbine 7 to decrease, and the air passing through the bearings 15 and 16 dries the lubricant in the bearings 15 and 16 or has dust. There is a risk that the inside of the bearings 15 and 16 may be soiled to reduce the durability. Such a decrease in efficiency and the fouling of the bearings 15 and 16 are prevented by the non-contact seals 21 and 22.

Since the sensor 18 applies a preload, even if the sensor 18 can only detect the pressing force, the sensor 18 can detect any movement of the main shaft 13 in the axial direction. That is, in the case of a sensor that detects by pressing force, detection cannot be performed when the pressing force is negative, but preloading reduces the pressing force that acts on the sensor 18 in the case of a negative thrust force. Can be detected.
Since the first spring element 25 that preloads the sensor 18 has a larger spring constant than the second spring element 26 that preloads the bearings 15 and 16, the first spring element 25 depends on the preload of the sensor 18 even if the bearings 15 and 16 are preloaded. Both forward and reverse directions can be detected.

Each of FIGS. 3 and later, shows the details or the like of each of the other embodiments or sensor 18, in the present invention. However, the sensors shown in FIGS. 13 to 15 do not constitute the present invention, but are shown as reference examples. In each example after FIG. 3, the configuration and effects are the same as those in the example of FIG. 2 except for the matters specifically described, and the same reference numerals are given to the corresponding parts, and redundant explanations are omitted.

FIG. 3 shows another embodiment of the present invention. In this example, the arrangement of the spring elements 25 and 26 and the sensor 18 is changed with respect to the example of FIG. In this example, the bearing housing 23 to which the bearing 16 on the turbine impeller 7a side is fixed has an inner flange 23a on the shaft end side, and the width surface of the bearing housing 23 on the inner flange 23a side and the spindle housing opposite to this. A sensor 18 is arranged between the 14 side surfaces.
The first spring element 25 is disposed between the outer ring 16 a of the bearing 16 and the electromagnet 17 and preloads the sensor 18 via the outer ring 16 a and the inner flange 23 a of the bearing housing 23. The second spring element 26 is interposed between the outer ring 15b of the bearing 15 on the compressor impeller 6a side and the electromagnet 17, and preloads the bearing 15. Therefore, the direction of the contact angle generated in the bearings 15 and 16 is opposite to that in the example of FIG.

  In the case of this configuration, the arrangement of the sensor 18 and the direction of the preload by the spring elements 25 and 26 are opposite to the example of FIG. 2, but also in this example, the sensor 18 is arranged in the vicinity of the bearing 16. The thrust force acting on 16 can be directly detected. Moreover, each effect demonstrated in the example of FIG. 2 is obtained.

  In the example of FIG. 4, the outer ring 15 b of the bearing 15 on the sensor non-arrangement side is fixed to the inner periphery of a bearing housing 27 separate from the spindle housing 14. The bearing housing 27 has inner flanges that respectively engage with the width surfaces on both sides of the outer ring 15b, and is fitted in an inner diameter hole 28 provided in the spindle housing 14 so as to be axially movable. The second spring element 26 pre-loads the outer ring 15 b via the bearing housing 27.

  In the example of FIG. 5, the bearing housing 27 in which the outer ring 15b of the bearing 15 on the sensor non-positioning side is fixed to the spindle housing 14 by two leaf springs 29 in the example shown in FIG. . The leaf spring 29 is a second spring element that preloads the bearing 15.

  In the case of this configuration, the leaf spring 29 serves as both means for supporting the bearing housing 27 and preloading means for the bearings 15 and 16, so that the configuration is simple. The leaf spring 29 has a plate shape, but has a high rigidity in the radial direction, which is the planar direction, and the bearing 15 can be reliably supported even by the support by the leaf spring 29. The reason why the two leaf springs 29 are separated from each other in the axial direction is that it is difficult to stably support the bearing 15 because the moment load acts on one leaf spring 29.

  The example of FIG. 6 is an example in which the second spring element 26 for applying a preload to the bearing 15 on the non-sensor arrangement side is arranged on the rotation side in the example of FIG. In this example, the second spring element 26 is disposed between the width surface of the inner ring 15a and the step surface of the main shaft 13 facing the width surface.

FIG. 7 shows a specific example of the sensor 18 used in the embodiment shown in FIG. This sensor 18 is configured such that a magnetostrictive material 31 is sandwiched between two yoke members 32 made of a soft magnetic material, and a coil 33 for detecting the magnetic permeability is provided on the outer periphery of each magnetostrictive material 31. The yoke member 32 is a ring-shaped plate member having a main shaft through hole 32a, and a set of the magnetostrictive material 31 and the coil 33 is provided at a plurality of locations in the circumferential direction. The magnetostrictive material 31 may be a giant magnetostrictive material.
Two or more magnetostrictive materials 31 are preferably provided to prevent tilting, and more preferably three or more. In this example, four are equally arranged in the circumferential direction.

According to the sensor 18 having this configuration, the magnetic flux due to the current flowing through the coil 33 is indicated by an arrow in the figure. When a pressure acts between the yoke members 32 in FIG. 7 due to the thrust force acting on the bearing 16 in FIG. 2, the magnetic permeability of the magnetostrictive material 31 changes and the inductance changes. This change in the inductance is detected by the coil 33, and the thrust force can be detected from the detected value.
If a plurality of magnetostrictive members 31 are provided around the spindle axis as shown in the figure, the yoke member 32 is prevented from tilting, and the thrust force can be detected stably. If the number of magnetostrictive materials 31 is three or more, the inclination is more stable. Further, for example, by connecting each coil 33 so as to be connected in series with the adjacent coil 33, the thrust force acting on the entire circumference of the yoke member 32 can be detected by averaging.

  In the sensor 18 of FIG. 7, as shown in FIG. 8, a second yoke member 34 made of a soft material that is slightly shorter than the magnetostrictive material 31 is arranged between the two yoke members 32. good. The second yoke member 34 has, for example, a ring shape similar to that of the two yoke members 32 described above, and has a coil receiving hole 34a into which each coil 33 is fitted with a gap. For example, the second yoke member 34 is overlapped and fixed to one of the two yoke members 32. The magnetostrictive material 31 may be a giant magnetostrictive material. The gap d34 due to the small difference in length is not limited as long as the load does not directly act between the two yoke members 32. For example, the gap d34 has a gap dimension of several tens to several hundreds of microns.

  By providing the second yoke member 34 as described above, the magnetic resistance of the magnetic path of the coil 33 is reduced, and the sensitivity of the sensor 18 is improved.

  FIG. 9 shows a sensor 18 shown in FIG. 8 in which an excitation coil 35 is provided in addition to a coil 33 for detecting the magnetic permeability of the magnetostrictive material 31 and provides a carrier wave for carrying the signal of the coil 33.

In the example of FIG. 10, in the sensor 18 shown in FIG. 7, a permanent magnet 36 magnetized in the thickness direction is provided in close contact with the end face of the magnetostrictive material 31. The magnetostrictive material 31 and the permanent magnet 36 are sandwiched between two yoke members 32 made of a soft material.
When the permanent magnet 36 is provided in this way, a bias magnetic field can be applied. Therefore, it is possible to select a portion where the change in the magnetic permeability in the magnetization curve of the magnetostrictive material 31 is large and use it for the detection, thereby improving the detection sensitivity. Alternatively, the control can be facilitated by using a portion having excellent linearity of change in magnetic permeability.

  In the example of FIG. 11, the second yoke member 34 is provided in the sensor 18 provided with the permanent magnet 36 shown in FIG. 10 as in the example of FIG. 8.

  In the sensor 18 shown in FIG. 12, a permanent magnet 36 magnetized in the thickness direction is provided in close contact with the end face of the magnetostrictive material 31 as in the example of FIG. Is sandwiched at a plurality of locations in the circumferential direction between the two yoke members 32 made of a soft material. However, in this example, as a means for detecting the magnetic permeability of the magnetostrictive material 31, a Hall element 37 is provided instead of the coil. The Hall element 37 is disposed between the magnetostrictive materials 31 arranged in the circumferential direction. The Hall elements 37 are attached to the tip of a second yoke member 34A partially provided on the opposing surface of one yoke member 32, and are close to the other yoke member 32.

  In the case of this configuration, a change in the magnetic permeability of the magnetostrictive material 31 becomes a change in the magnetic resistance of the magnetic circuit, a change in the magnetic flux density passing through the Hall element 37, and is detected as a change in the output of the Hall element 37. Also in this example, since the permanent magnet 36 is provided, a portion where the change in the output of the Hall element 37 due to the change in the magnetic permeability of the magnetostrictive material 31 due to the bias magnetic field can be used for detection, and the sensitivity can be improved. .

The sensor 18 shown in FIG. 13 has pressure sensitive resistance elements 39 interposed at a plurality of locations in the circumferential direction between two yoke members 32. A temperature sensor 40 is attached to the yoke member 32 located around the pressure-sensitive resistance element 39, and the resistance value of the pressure-sensitive resistance element 39 is corrected by the output of the temperature sensor 40.
According to the sensor 18 having this configuration, the resistance value of the pressure-sensitive resistance element 39 is changed by the force F acting between the two yoke members 32. By detecting this change in resistance value, the force F acting between the two yoke members 32 can be detected, and the thrust force of the main shaft 13 in the turbine unit 5 can be detected in FIG.

  The sensor 18 shown in FIG. 14 has a configuration in which an elastic body 45 is inserted between the pressure-sensitive resistance element 39 and the yoke member 32 having the sensor structure shown in FIG. By sandwiching the elastic body 45, the pressure is applied evenly to the pressure sensing part of the pressure-sensitive resistance element 39, and measurement errors due to the local application of pressure can be reduced.

The sensor 18 shown in FIG. 15 has a disc spring 41 concentric with the yoke members 32 between two yoke members 32, and has strain gauges 43 attached to a plurality of locations in the circumferential direction of the disc spring 41. is there. In this example, the temperature sensor 40 is attached to the yoke member 32 located around the strain gauge 43, and the resistance value of the strain gauge 43 is corrected by the output of the temperature sensor 40.
According to the sensor 18 with this configuration, the disc spring 41 is bent by the force F acting between the two yoke members 32, and this bending changes the resistance value of the strain gauge 43. A change in the resistance value of the strain gauge 43 is detected as a change in the output of the strain gauge amplifier.

FIGS. 16 to 24 show examples of sensor circuits and sensor outputs of the sensors 18, respectively.
FIG. 16 shows an example of a sensor circuit 50 in the case of a sensor 18 provided with a coil 33, such as the sensor 18 shown in FIG. The sensor circuit 50 generates a carrier wave having a constant amplitude and a constant frequency by the carrier wave generation circuit 51 and transmits the carrier wave to the coil 33 through the capacitor Co. The coil 33 forms a parallel resonance circuit with the capacitor C, and the output of the parallel resonance circuit is connected to the amplitude detection circuit 52.

  In the above resonance circuit, when the input ei and the output eo are used, the value of the transfer function eo / ei changes depending on the input frequency f. When the inductance of the coil 33 is L and the capacitance of the capacitor C is C, the peak value of the transfer function eo / ei is 1 / (2π√LC). The value of the inductance L of the coil 33 changes according to this change because the magnetic permeability of the magnetostrictive material 31 (FIG. 7) changes with the force F as described above. Therefore, by applying a voltage having a constant amplitude and a constant frequency by the carrier wave generating circuit 51 and exciting the resonance circuit, the value of the transfer function eo / ei at a predetermined frequency is changed by the change of the force L, that is, the change of the inductance L. change. The amplitude detection circuit 52 detects the change of the transfer function eo / ei and sets it as the sensor output Vo.

  When a plurality of coils 33 are provided as in the example of FIG. 7, the sensor circuit 50 may be provided for each individual coil 33. However, as shown in FIG. You may make it detect by. The winding directions of the adjacent coils 33 are different in various directions. Thus, by connecting the coils 33 in series, the force acting on the magnetostrictive material 31 corresponding to each coil 33 is averaged and taken out as a sensor output Vo.

  In the sensor circuit 50 of FIGS. 16 and 17, the relationship between the force F applied to the magnetostrictive material 31 and the inductance L, and the relationship between the force F and the sensor output Vo are as shown in FIGS. 18 (A) and 18 (B). become. In this case, applying a force in the minus direction means that the facing portion that exerts pressure on the magnetostrictive material 31 is separated from the magnetostrictive material 31 and cannot be detected. Therefore, an initial preload amount is given as shown in FIG. Thus, even if the thrust force acts in either forward or reverse direction, the thrust force can be detected by the difference from the sensor output at the initial preload amount.

  19 and 20 show a sensor circuit 53 of the sensor 18 using the pressure sensitive resistance element 39 of FIG. The sensor circuit 53 connects a series circuit of the pressure-sensitive resistor element 39 and the fixed resistor R1 to the power supply 61, and a sensor output Vo from a connection point between the pressure-sensitive resistor element 39 and the fixed resistor R1 that is an intermediate part of the series circuit. To take out.

As shown in FIG. 20A, the pressure-sensitive resistance element 39 increases in resistance R as the applied force F increases. Therefore, the voltage dividing resistance ratio of the series circuit increases, and the sensor output Vo increases as the force F increases as shown in FIG.
Applying a force in the negative direction means that the opposing portion that exerts pressure on the pressure-sensitive resistance element 39 is separated from the pressure-sensitive resistance element 39, and the pressure-sensitive resistance element 39 cannot measure a negative force. By giving an initial preload amount as shown in 20 (A) and (B), the difference from the sensor output at the time of the initial preload amount is measured regardless of whether the force F is applied in the forward or reverse direction. Can do.

FIG. 21 shows an example of another sensor circuit 54 for the sensor 18 using the pressure sensitive resistance element 39 of FIG. This sensor circuit 54 has a fixed resistor R ′ connected between the inverting input terminal and the output terminal of the operational amplifier OP1, one end of the pressure-sensitive resistor element 39 connected to the inverting input terminal, and a constant voltage V applied to the other end. It is.
In this sensor circuit 54, if the resistance of the pressure-sensitive resistance element 39 is R, the sensor output Vo is -R '/ R * Vi. Therefore, as shown in FIG. 22, the sensor output Vo increases as the force F applied to the pressure sensitive resistance element 39 increases.

  When a plurality of pressure-sensitive resistor elements 39 are provided as in the example of FIG. 13, a sensor circuit 54 may be provided for each pressure-sensitive resistor element 39, and the pressure-sensitive resistor elements 39 are arranged in parallel as shown in FIG. It is also possible to connect between the operational amplifier OP1 and the power supply, and detect with one sensor circuit 50. In this case, the force F applied to the pressure sensitive resistance element 39 at each position is averaged and appears in the sensor output Vo.

  FIG. 24 shows a specific configuration example of the controller 19 shown in FIG. The controller 19 is an example in the case where a sensor circuit 53 is provided for each pressure-sensitive resistance element 39 in FIG. Reference numerals with parentheses shown in each sensor circuit 53 are codes for distinguishing the four sensor circuits 53. The sensor circuit 53 shown in the figure may be the sensor circuit 50 for the coil 33 shown in FIG.

The outputs of the sensor circuits 53 are arithmetically averaged by the averaging circuit 55, compared with the reference value set in the reference value setting means 56 by the comparison unit 57, and the deviation is taken. The reference value is, for example, a value corresponding to the preload setting amount. For example, the detection value of the temperature sensor 40 in FIG. 13 is input to the sensor correction amount calculation circuit 59 via the temperature detection circuit 58, and the sensor correction amount calculation circuit 59 outputs a correction value corresponding to the temperature. This correction value is added to the deviation by the comparison unit 57.
The PID compensation circuit 60 processes the deviation after the temperature correction by proportional, differential, and integral operations that are appropriately set according to the turbine unit 5.

  The output of the PID compensation circuit 60 is input to power circuits 63 and 64 that drive the electromagnets 171 and 172 in each direction via diodes 61 and 62, respectively. The electromagnets 171 and 172 are a pair of electromagnets 17 opposed to the thrust plate 13a shown in FIG. 2, and only the attractive force acts. Therefore, the direction of current is determined in advance by the diodes 61 and 62, and the two electromagnets 171 and 172 are used. Is driven selectively.

FIG. 25 shows a turbine unit 5 according to still another embodiment. In the example shown in FIG. 2, the turbine unit 5 is provided with a plurality of thrust plates 13 a made of a ferromagnetic material provided on the main shaft 13. The electromagnet 17 is installed on the spindle housing 14 so as to face both surfaces of each thrust plate 13a.
Each electromagnet 17 is divided into a plurality of electromagnet divisions 17A and 17B arranged in the circumferential direction, as shown in FIG. Each of the electromagnet divisions 17A and 17B has a coil 17a and a yoke. This division enables assembly while providing a plurality of thrust plates 13a.

In the case of this configuration, the following action is obtained. That is, in the turbine unit 5, when the thrust force due to air pressure is large, it is desirable to increase the diameter of the thrust plate 13 a and increase the force of the electromagnet 17. However, at high speed rotation, there is a risk of being destroyed by centrifugal force, and there is a limit to increasing the diameter of the thrust plate 13a.
As in the example of FIG. 25, when a plurality of thrust plates 13a are used, the supporting force against the thrust force can be increased without causing a problem of destruction due to centrifugal force.

  FIG. 26 shows a turbine unit 5 according to still another embodiment. The turbine unit 5 is provided with a motor 90 that rotationally drives the main shaft 13. The motor 90 is provided side by side with the electromagnet 17 and includes a stator 91 provided on the spindle housing 14 and a rotor 92 provided on the main shaft 13. The stator 91 has a stator coil 91a, and the rotor 92 is made of a magnet or the like. The motor 90 is controlled by a motor controller 93.

  In the turbine unit 5, the compressor impeller 6 a is rotationally driven by the driving force of the turbine impeller 7 a generated in the expansion turbine 7 and the driving force of the motor 90. Therefore, the compressor 6 can be driven to rotate without the pre-compression means 2 comprising the blower of FIG.

1 is a system diagram of an air cycle refrigeration cooling system using an air cycle refrigeration cooling turbine unit according to an embodiment of the present invention. It is sectional drawing of the turbine unit for air cycle refrigeration cooling which concerns on 1st Embodiment of this invention. It is sectional drawing of the turbine unit for air cycle refrigeration cooling which concerns on other embodiment. It is sectional drawing of the turbine unit for air cycle refrigeration cooling which concerns on other embodiment. It is sectional drawing of the turbine unit for air cycle refrigeration cooling which concerns on other embodiment. It is sectional drawing of the turbine unit for air cycle refrigeration cooling which concerns on other embodiment. It is the front view of the sensor used for the turbine unit of each said embodiment, and its VII-VII sectional view taken on the line. It is the front view of the other example of the sensor used for the turbine unit of each said embodiment, and its VIII-VIII sectional view taken on the line. It is the front view of the further another example of the sensor, and its IX-IX sectional view. It is the front view of the further another example of the sensor, and its XX sectional view. It is the front view of the further another example of the sensor, and its XI-XI sectional view taken on the line. It is the front view of the further another example of the sensor, and its XII-XII sectional view taken on the line. It is sectional drawing of the reference example of the sensor, and its XIII-XIII arrow directional view. It is sectional drawing of the other reference example of the sensor, and its XIV-XIV arrow directional view. It is sectional drawing of the other reference example of the sensor, and its XV-XV arrow directional view. It is a block diagram which shows an example of the sensor circuit used for the turbine unit of each said embodiment. It is a block diagram which shows the other example of the sensor circuit. It is a graph which shows the relationship between the force and inductance in the sensor circuit, and the graph which shows the relationship between force and a sensor output. It is a block diagram showing other examples of the sensor circuit. It is the graph which shows the relationship between the force and resistance value in the sensor circuit, and the graph which shows the relationship between force and a sensor output. It is a block diagram showing other examples of the sensor circuit. It is a graph which shows the relationship between the force and sensor output in the sensor circuit. It is a block diagram showing other examples of the sensor circuit. It is a block diagram which shows an example of the controller used for the turbine unit of each said embodiment. (A), (B) is the longitudinal cross-sectional view of the turbine unit for air cycle refrigeration cooling which concerns on further another embodiment, respectively, and the cross-sectional view of the electromagnet. It is sectional drawing of the turbine unit for air cycle refrigeration cooling which concerns on other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Air circulation path 1a ... Intake port 1b ... Exhaust port 2 ... Precompression means 3 ... 1st heat exchanger 5 ... Air cycle refrigeration cooling turbine unit 6 ... Compressor 6a ... Compressor impeller 7 ... Expansion turbine 7a ... Turbine blade Car 8 ... Second heat exchanger 9 ... Intermediate heat exchanger 10 ... Space to be cooled 13 ... Main shaft 13a ... Thrust plate 14 ... Spindle housing 15, 16 ... Bearing 17 ... Electromagnet 18 ... Sensors 19, 19A ... Controllers 21 and 22 ... non-contact seal 23 ... bearing housing 25 ... first spring element 26 ... second spring element 29 ... leaf spring 31 ... magnetostrictive material 32 ... yoke member 33 ... coil 34 ... second yoke member 35 ... exciting coil 36 ... permanent magnet 37 ... Hall element 39 ... pressure sensitive resistance element 40 ... temperature sensor 41 ... disc spring 42 ... strain gauge 45 ... elastic bodies 50, 53, 54 ... sensor circuit 6 To 64 ... Pressure sensor (pressure measuring means)
65-68 ... temperature sensor 81 ... pressure equalizing means 83 ... vent passages 84, 85 ... bearing cooling air introduction passage 86 ... bearing cooling air introduction passage 70 ... outflow passage 90 ... motor 93 ... motor controller

Claims (21)

An air cycle refrigeration cooling turbine unit having a compressor and an expansion turbine, wherein the compressor impeller of the compressor and the turbine impeller of the expansion turbine are attached to a common main shaft, and the compressor blade is generated by power generated by the turbine impeller. car is driven, or all SANYO for rotating the compressor wheel by the compressor wheel and rotor on a common spindle which turbine wheel is attached rotates the spindle by the motor is attached,
An air-cooling turbine unit that rotatably supports the main shaft by a rolling bearing and supports a part or all of the thrust force applied to the main shaft by an electromagnet according to an output of a sensor that detects a thrust force acting on the main shaft. ,
The sensor is arranged on the stationary side in the vicinity of the rolling bearing , and the sensor has a sensor element whose characteristics are changed by the pressing force, and sensor elements that can electrically detect the characteristic change are arranged around the spindle axis in the circumferential direction. The thrust force is detected from the outputs of the plurality of sensor elements, and is interposed between an outer ring of the rolling bearing and a spindle housing that supports the outer ring ,
The sensor detects thrust force by detecting the permeability of a plurality of magnetostrictive materials or giant magnetostrictive materials arranged side by side in the circumferential direction around the spindle axis. The magnetostrictive material is sandwiched between two yoke members made of a soft magnetic material.
An air cycle refrigeration cooling turbine unit. 2. The air cycle refrigeration cooling turbine unit according to claim 1 , wherein a second yoke member made of a soft magnetic material that is slightly shorter than the magnetostrictive material or the giant magnetostrictive material is disposed between the two yoke members. . An air cycle refrigeration cooling turbine unit having a compressor and an expansion turbine, wherein the compressor impeller of the compressor and the turbine impeller of the expansion turbine are attached to a common main shaft, and the compressor blade is generated by power generated by the turbine impeller. A motor rotor is attached to a common main shaft to which the car is driven or the compressor impeller and the turbine impeller are attached, and the compressor impeller is rotated by rotating the main shaft by the motor.
An air-cooling turbine unit that rotatably supports the main shaft by a rolling bearing and supports a part or all of the thrust force applied to the main shaft by an electromagnet according to an output of a sensor that detects a thrust force acting on the main shaft. ,
The sensor is arranged on the stationary side in the vicinity of the rolling bearing, and the sensor has a sensor element whose characteristics are changed by the pressing force, and sensor elements that can electrically detect the characteristic change are arranged around the spindle axis in the circumferential direction. The thrust force is detected from the outputs of the plurality of sensor elements, and is interposed between an outer ring of the rolling bearing and a spindle housing that supports the outer ring,
The sensor detects thrust force by detecting the permeability of a plurality of magnetostrictive materials or giant magnetostrictive materials arranged in a circumferential direction around the spindle axis.
Permanent magnets magnetized in the thickness direction are provided in close contact with the end face of the magnetostrictive material or giant magnetostrictive material, and these two magnetostrictive materials or giant magnetostrictive material and permanent magnet are made of a soft material. Turbine unit for air cycle refrigeration cooling sandwiched between members. 4. The second yoke member according to claim 3 , wherein the second yoke member is made of a soft magnetic material that is slightly shorter than a length in which the magnetostrictive material or super magnetostrictive material and the permanent magnet are overlapped between the two yoke members. Arranged turbine unit for air cycle refrigeration cooling. 5. The sensor according to claim 1 , wherein the sensor includes a sensor coil disposed around a magnetostrictive material or a giant magnetostrictive material, and the permeability of the magnetostrictive material or the giant magnetostrictive material is determined by an inductance of the sensor coil. A turbine unit for air cycle refrigeration cooling, which is detected by measuring. 6. The air cycle refrigeration cooling turbine unit according to claim 5 , wherein a plurality of the sensors are provided, the sensor coils of the plurality of sensors are connected in series, and the outputs of the sensor coils are averaged. 7. The air cycle refrigeration cooling turbine unit according to claim 6 , wherein the sensor coil and the magnetostrictive material or the giant magnetostrictive material are an even number, and currents flowing in adjacent sensor coils are in opposite directions. 8. The inductance change according to claim 5 , wherein the sensor uses resonance between an inductance of the sensor coil and a separate capacitor, and changes the inductance from a change in resonance frequency that changes due to a change in the inductance. Turbine unit for air cycle refrigeration cooling that measures. 8. The sensor according to claim 5 , wherein the sensor includes an excitation coil around a magnetostrictive material or a giant magnetostrictive material in addition to the sensor coil, and the excitation coil has an alternating current excitation having a constant frequency and a constant amplitude. An air cycle refrigeration cooling turbine unit for measuring a thrust force by flowing a current and detecting a voltage excited in the sensor coil. 5. The thrust force according to claim 1 , wherein the sensor uses a Hall sensor to detect a magnetic flux density that changes with a change in permeability of the magnetostrictive material or the giant magnetostrictive material. Turbine unit for air cycle refrigeration cooling to be measured. 11. The sensor according to claim 1 , wherein the sensor includes a sensor coil disposed around a magnetostrictive material or a giant magnetostrictive material, and the permeability of the magnetostrictive material or the giant magnetostrictive material is determined according to an inductance of the sensor coil. A temperature sensor disposed around the magnetostrictive material or the giant magnetostrictive material, and means for correcting the measurement result of the inductance or the measurement result of the magnetic permeability by the output of the temperature sensor Turbine unit for air cycle refrigeration cooling provided. 12. The sensor according to claim 1 , wherein the sensor is interposed directly or via another member between an outer ring of the rolling bearing and a spindle housing that supports the outer ring. Turbine unit for air cycle refrigeration cooling. 13. The bearing housing according to claim 12 , wherein the outer ring of the rolling bearing is fitted in a fixed state, is fitted in an inner diameter hole provided in the spindle housing so as to be movable in the axial direction, and the sensor is connected to the width surface of the bearing housing. An air cycle refrigeration cooling turbine unit interposed between the spindle housing or a member fixed to the spindle housing. The turbine unit for air cycle refrigeration cooling according to any one of claims 1 to 13 , wherein the sensor is applied with a preload by a first spring element. Oite to claim 14, wherein the first preload of the spring elements, the compressor and the average thrust force more air cycle refrigeration cooling turbine unit is sized to act on the main shaft by the air in the expansion turbine. 16. The rolling bearing according to claim 12 , wherein a plurality of the rolling bearings are provided, the sensor is disposed in the vicinity of one of the rolling bearings, and the other rolling bearing is in an axial direction with respect to the spindle housing. A turbine unit for air-cycle refrigeration cooling that is movably installed in the vehicle and elastically supported by a second spring element. 17. The second spring element according to claim 16 , wherein the second spring element is between the outer ring of the other rolling bearing and the spindle housing, or between the member that fixes the outer ring of the other rolling bearing and the spindle housing, or the rolling housing. An air cycle refrigeration cooling turbine unit interposed between an inner ring of a bearing and the main shaft. 18. The air cycle refrigeration cooling according to claim 16 , wherein the sensor is preloaded by a first spring element, and the second spring element has a smaller spring constant than the first spring element. Turbine unit. 19. The flange according to claim 1 , wherein a plurality of flange-shaped thrust plates made of a ferromagnetic material are provided on the main shaft, and the electromagnets are installed on the spindle housing so as to face the width surfaces on both sides of each thrust plate. Turbine unit for air cycle refrigeration cooling. The air cycle refrigeration cooling turbine unit according to claim 19, wherein the electromagnet is divided into a plurality of pieces arranged in a circumferential direction. The turbine unit for air cycle refrigeration cooling according to claim 20, wherein the number of poles and the size of each of the electromagnets divided into a plurality and the number of turns of the incorporated coil are the same.

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