JP2828938B2 - Gas compression / expansion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas compression / expansion apparatus for a Stirling cycle engine, a Bulmier cycle engine, a pulse tube cycle engine or the like, and more particularly, a crank mechanism for driving a piston or a displacer. The present invention relates to a device for controlling an oil level in a drive chamber.

[0002]

2. Description of the Related Art Generally, a gas compression / expansion device of this type generates a low or high temperature by repeating a cycle of reciprocating a piston or a displacer to compress or expand a gas in a working chamber, or vice versa. By raising or lowering the temperature of the working chamber, the gas expands or contracts, and the piston or the displacer is reciprocated to extract driving force. In order to reciprocate the piston or displacer, a crank mechanism is arranged in the drive chamber together with oil. And since the function of the device is reduced when oil is mixed into the working chamber, a partition wall is provided between the working chamber and the drive chamber, and an oil seal is attached to the partition wall to penetrate the rod. The piston or displacer is connected to the crank mechanism to prevent oil from entering the working chamber from the driving chamber.

[0003]

Heretofore, it has not been practiced to separately control the oil level by merely charging a fixed amount of oil in the drive chamber in which the crank mechanism is housed. However, the crank mechanism has a large number of bearings, and in the initial stage of driving, the oil is insufficient and the oil does not reach all the bearings sufficiently, causing wear on the bearings. It was found that the oil filled in the room entered the working chamber through the oil seal.

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a gas compression / expansion device which controls the oil in a driving chamber always to an optimum amount and smoothly drives a crank mechanism.

[0005]

According to a first aspect of the present invention, there is provided a cylinder chamber in which a piston or a displacer reciprocates, and a drive chamber in which a crank mechanism connected to the piston or the displacer via a rod is stored together with oil. And a mechanism for supplying oil accumulated in the drive chamber along with rotation of the crank mechanism to bearings of each part of the crank mechanism while the rod is partitioned by a partition wall through which the rod passes through an oil seal. Gas compression
In the expansion device, connected to the drive chamber via an oil pipe having a valve and an oil pipe having a pump,
An oil tank for supplying and collecting oil to the drive chamber,
An oil control device that supplies oil from the oil tank to increase the oil level in the drive chamber at the beginning of operation, and collects the oil in the oil tank to reduce the oil level in the drive chamber during stable operation. Features.

Thus, at the initial stage of operation of the gas compression / expansion device, oil is sufficiently supplied to the bearings of the crank mechanism to prevent problems such as abrasion. It is possible to prevent the excess oil from entering the working chamber from the driving chamber by adjusting the amount.

According to a second aspect of the present invention, a first oil level detector for detecting an oil level at which the balancer and the oil splasher are sufficiently immersed is provided in the driving chamber of the gas compression / expansion device according to the first aspect. A second oil level detector for detecting an oil level at which only the splasher is immersed; the crank mechanism includes a crankshaft that is rotationally driven by a driving source; and a connecting rod having one end connected to the crankshaft. A cross guide connected to the other end of the connecting rod, a balancer connected to the crankshaft,
An oil splasher that is connected to the crankshaft and scrapes oil accumulated on the bottom surface with the rotation of the crankshaft, an oil sump that stores oil scraped by the oil splasher, and formed inside the crankshaft. An oil passage for supplying oil from the oil sump to each bearing of the crank mechanism, and the oil control device controls the pump and the valve so that the oil in the drive chamber can be controlled before starting operation. Means for controlling the oil level detected by the first oil level detector, and means for controlling the oil in the drive chamber to the oil level detected by the second oil level detector during stable operation. It is characterized by.

According to this structure, the driving room is always controlled to an appropriate oil level during operation by the oil control device and the respective oil level detectors, and oil is formed from the oil reservoir into the crankshaft. The oil is supplied satisfactorily to the bearings through the oil passages, thereby reliably preventing wear and the like at the beginning of operation and preventing excess oil from entering the working chamber during stable operation.

According to a third aspect of the present invention, the crank mechanism according to the first aspect includes a crankshaft that is rotationally driven by a drive source, a connecting rod having one end connected to the crankshaft, and the other end of the connecting rod. A cross guide connected to the crankshaft, a balancer connected to the crankshaft, an oil splasher connected to the crankshaft to scrape oil accumulated on the bottom surface with rotation of the crankshaft, An oil sump for storing oil scooped up by a washer, and an oil passage formed inside the crankshaft for supplying oil from the oil sump to each bearing of a crank mechanism, and operating the oil control device. Open the valve for a first predetermined time from the start and open the drive chamber Means for controlling the oil level to an oil level at which the balancer and the oil splasher are sufficiently immersed, and further driving the pump for a third predetermined time after a lapse of a second predetermined time to reduce the oil in the drive chamber to the oil splasher. Means for controlling the oil level so that only the oil is immersed therein, and means for driving the pump for a fourth predetermined time after the operation is completed to return all the oil in the drive chamber to the oil tank.

According to this structure, the oil level in the drive chamber during operation is controlled to an appropriate value during operation simply and economically without providing an oil level detector in the drive chamber. 2 Similarly, oil is supplied from the oil reservoir to the bearings through oil passages formed inside the crankshaft to prevent wear at the initial stage of operation and prevent excess oil from entering the working chamber during stable operation. Is performed reliably.

According to a fourth aspect of the present invention, the gas compression / expansion device according to the second or third aspect further comprises a lower limit level detecting means for detecting that the oil level in the drive chamber has reached a lower limit level. The oil control device is characterized in that a means is provided for forcibly opening the valve for a predetermined time according to the lower limit level detecting means.

With this configuration, there is no danger that the oil falls below the lower limit level during operation and the oil does not turn around the bearing, and a highly reliable gas compression / expansion device can be obtained.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment of the present invention will be described below with reference to the drawings, taking an example in which the present invention is applied to a Stirling refrigerator.

FIG. 1 shows an example of a Stirling refrigerator to which the present invention is applied. The Stirling refrigerator shown in this embodiment includes a gas expander 1 for generating refrigeration heat and a gas expander 1 from the gas expander 1. A gas compressor 2 which receives and compresses the expanded working gas and returns it;
And a drive chamber 3 for operating the heat exchanger. A regenerator 4 functioning as a regenerator is interposed between the gas expander 1 and the gas compressor 2 to provide a heat exchanger 5 for extracting refrigeration heat and a heat exchanger for releasing heat. A gas flow path is formed by being connected to the heat exchanger 6.

The gas expander 1 expands the compressed working gas supplied from the gas compressor 2 via the regenerator 4 to generate cold heat. Is slidably fitted in The inside of the expansion cylinder 7 is partitioned by a piston ring of an expansion piston 8, and the front space is used as an expansion space 9 for generating a low temperature.

The gas compressor 2 compresses a working gas having a very low boiling point such as helium in accordance with a predetermined cycle and supplies the compressed working gas to the gas expander 1. A compression piston 11 is slidably fitted in the left-right direction inside the compression piston 11. Compression cylinder 10
The inside is partitioned by a piston ring of a compression piston 11, and the front space thereof is used as a compression space 12.

The drive chamber 3 includes an expansion piston 8 and a compression piston 11 which are driven by a drive motor (not shown) as a drive source.
A crank mechanism 13 for reciprocating with a phase difference of 0 ° is housed together with a lubricating oil 14. Rods 15, 1 are provided between the pistons 8, 11 and the crank mechanism 13.
6 and is separated from the cylinder chamber by a partition wall provided with oil seals 17 and 18. Further, since the rotational movement of the crank mechanism 13 is converted into the linear movement of the pistons 8 and 11, the rods 15 and 16 are provided with a joint mechanism on the way as described later.

The regenerator 4 functions as a regenerator in the present embodiment, and cools the working gas compressed in the course of being supplied from the gas compressor 2 to the gas expander 1, while expanding the gas by the gas expander 1. The cooled and cooled low-temperature working gas is cooled by the low-temperature working gas on the way to return to the gas compressor 2 and accumulates cold. As its material, for example, stainless steel, ceramic, copper, lead, or the like is used. They are provided with a large number of fine holes through which a working gas passes.

The heat exchangers 5 and 6 according to the present invention have the same configuration, in which fins 20 are erected on the outer peripheral surface of a tubular body 19 formed of a flexible material having good thermal conductivity such as copper. The heat exchanger 5 is for taking out the low temperature generated in the expansion space 9 to the outside, and the heat exchanger 6 is for radiating the high temperature generated in the compression space 12.

In this configuration, when the crank mechanism 13 is driven by the rotation of a drive motor (not shown), the compression piston 11 in the compression cylinder 10 of the gas compressor 2 moves toward the compression space 12 and Liquefied working gas, such as helium, which fills the space, is compressed. When the compressed working gas passes through the heat exchanger 6 acting as a radiator, the heat generated at the time of compression is radiated to the outside, cooled to around room temperature, and flows into the regenerator 4 acting as a regenerator.

The working gas flowing into the regenerator 4 is cooled and flows into the expansion space 9 of the gas expander 1, whereby the space is brought into a high pressure state.

Thereafter, the expansion piston 8 in the expansion cylinder 7 of the gas expander 1 descends with a phase difference of about 90 ° from the compression piston 11, so that the expansion space is expanded and the inflowing high-pressure working gas is reduced. The working gas is cooled to a low temperature due to rapid expansion and a sudden drop in pressure.

Eventually, the expansion piston 8 starts to rise,
When the compression piston 11 retreats, the low-temperature working gas passes through the heat exchanger 5 so that the low-temperature working gas is taken out. The working gas returns from the regenerator 4 to the compression space 12 via the heat exchanger 6, but when passing through the regenerator 4, the internal members are cooled by the working gas and the regenerator 4 becomes low temperature.

As described above, the gas compressed in the compression space 12 is supplied to the expansion space 9 and expanded, and the step of returning the expanded gas to the compression space 12 again completes one heat cycle. The process is cyclically repeated by the rotation of the crank mechanism 13. As a result, the temperature of the working gas in the expansion space 9 and the temperature of the regenerator 4 gradually decrease to a low temperature. This low temperature is taken out of the heat exchanger 5 and the cooling load of a low-temperature tank (not shown) can be set to the freezing temperature.

Although the above is the same as the conventional case, in the case of the present invention, the oil pipe 22 having the valve 21 in the drive chamber 3 is provided.
And an oil tank 25 is connected via an oil pipe 24 having a pump 23, and an oil control device 26 for controlling the valve 21 and the pump 23 is provided.

FIGS. 2 and 3 show a detailed view of the drive chamber 3 in which an oil supply for supplying oil to a crank chamber 3a containing a crank portion and a crank mechanism is shown. It is lowered to the chamber 3b and is partitioned by the wall 30.

The lower wall 30 and the outer wall 31 of the drive room 3
A crankshaft 32 is provided through bearings 30a and 31a to be rotated by a motor (not shown). One end of a connecting rod 33 is connected to the crankshaft 32 via a bearing 33a. The other end of the connecting rod 33 is connected to a cross guide 34 forming one end of the piston rod 15 via a bearing 33b.

Therefore, when the crankshaft 32 rotates, the cross guide 3 is connected via the connecting rod 33.
When the guide 4 moves up and down through the bearing 34a, the rotary motion is changed to a linear motion, and the piston rod 15 is driven to reciprocate.

A connecting rod 35 for driving the compression piston 11 is also connected to the crankshaft 32 via a bearing 35a. A balancer 36 is connected to the crankshaft 32 in order to maintain balance when driving the pistons 8 and 11.

An oil passage 37 is formed inside the crankshaft 32 to supply oil to each bearing of the crank mechanism. To supply the oil 14 to the oil passage, an oil reservoir 38 is formed at the end of the crankshaft 32 on the oil supply chamber 3b side, and the oil is supplied to the oil reservoir 38 on the crankshaft 32 shaft near the oil reservoir 38. An oil splasher 39 for scraping is fixed.

With this configuration, the oil control device 26 is configured as shown in FIG.
As shown in (1), the valve 21 and the pump 23 are controlled.
That is, at the start of the operation, the valve 21 is opened for the time T1 so that the oil level in the drive chamber 3 is set to the L1 level at which the balancer 36 is immersed in order to sufficiently supply oil to each bearing of the crank mechanism. The time T1 at which the oil level is set to L1 is obtained by first collecting the drive chamber 3 in the oil tank 25 with no oil in the drive chamber 3 by using the pump 23, and then measuring the time required for the oil to reach the L1 level by opening the valve 21. Can be obtained. Experiments are repeated in the same manner for the time described below, and the required time is obtained.

By opening the valve 21 for T1 time,
When the oil in the drive room 3 reaches the L1 level, the operation of the Stirling refrigerator is started, and when the operation state of the refrigerator is stabilized after the elapse of the time T2, the pump 23 is driven for the time T3, and the drive room is driven. Oil from piston rods 15 and 16 from 3
To control the oil level L2 so that only the oil splasher 39 is immersed in the cylinder chamber.

Thereafter, when the oil level reaches the lower limit level during the operation at the L2 level, the valve 21 is again operated.
Is opened for T4 time to control the oil level in the drive chamber 3 to return to the L2 level. The lower limit of the oil level can be detected by measuring the operation time, but a lower limit detector may be specially installed.

When a stop operation is performed to stop the operation of the Stirling refrigerator, it is detected and the pump 2 is stopped.
3 is operated for T5, and all the oil in the drive chamber 3 is collected in the oil tank 25 in preparation for oil level control at the next operation.

By controlling the opening / closing time of the valve 21 and the operation time of the pump 23 in this manner, the driving room 3
The oil level is always controlled to an appropriate level even if no oil level detector is installed inside, and at the beginning of operation, oil is sufficiently supplied to each bearing of the crank mechanism to prevent problems such as wear and stabilization. During operation, the amount of oil in the drive room is adjusted to an appropriate amount to prevent a problem that surplus oil enters the drive room from the drive room.

FIG. 5 shows another example of the embodiment of the present invention, in which a detector for detecting the oil level of the driving chamber 3 is installed, and the output of the detector adjusts the oil level to an appropriate level. This is an example in the case of controlling to. In the figure, the same reference numerals as those in FIG. 2 indicate the same or corresponding parts, and the points different from the configuration in FIG.
An oil pipe 42 having a valve 41 is additionally provided to supply oil to the oil level L2 in the drive chamber 3, and an oil detector 43 for detecting the oil levels L1, L2, L3 respectively. , 44, and 45, and outputs of these detectors are input to the oil control device 26. As these oil detectors 43 to 45, long-wave detectors are used for installation outside the container, but it goes without saying that they are not limited to this.

With this configuration, the oil control device 26
As shown in the figure, at the start of operation, in order to supply oil sufficiently to each bearing of the crank mechanism, the valve 21 is opened until the oil detector 43 detects oil until the oil in the drive chamber 3 reaches the L1 level at which the balancer 36 is immersed. Supply.

When the oil in the drive chamber 3 reaches the L1 level, the operation of the Stirling refrigerator is started, and when the operation state of the refrigerator becomes stable after the elapse of the time T1, the pump 23 is operated.
Drive.

Next, in order to prevent oil from traveling from the driving chamber 3 through the piston rods 15 and 16 to enter the cylinder chamber, the valve 4 is operated until the oil detector 44 detects oil.
1 is opened to supply oil to an oil level L2 at which only the oil splasher 39 is immersed.

Thereafter, the refrigerator is operated at this L2 level,
When the oil detector 45 detects the lower limit level L3 during operation, the valve 21 is opened again and oil is supplied into the drive chamber 3 until the oil detector 44 detects the L2 level. Control to return to.

When a stop operation is performed to stop the operation of the Stirling refrigerator, the operation is detected and the pump 2 is stopped.
3 is operated until the oil detector 45 detects oil,
The oil in the drive chamber 3 is controlled to the lower limit oil level L3, and all operations are stopped.

[0042]

As described above, according to the configuration of the first aspect of the present invention, at the initial stage of operation of the gas compression / expansion device, oil is sufficiently supplied to each bearing of the crank mechanism, thereby preventing problems such as wear. At the same time, during stable operation, the amount of oil in the drive chamber is adjusted to an appropriate amount, thereby preventing a problem that surplus oil enters the working chamber from the drive chamber.

According to the second aspect of the invention, the inside of the drive room is always controlled to an appropriate oil level during operation by the oil control device and the respective oil level detectors, and oil is removed from the oil reservoir to the inside of the crankshaft. The bearings are satisfactorily supplied to the respective bearings through the oil passages formed at the beginning of the operation, and the ingress of excess oil into the working chamber during the stable operation and the stable operation can be reliably prevented.

According to the third aspect of the present invention, the oil level in the drive room during operation is controlled to an appropriate value while the operation is simple and economical without providing an oil level detector in the drive room. In the same manner as in claim 2, the oil is satisfactorily supplied from the oil reservoir to the respective bearings through an oil passage formed inside the crankshaft, and wear at the initial stage of operation, and intrusion of surplus oil into the working chamber during stable operation. Is reliably prevented.

According to the fourth aspect of the present invention, there is no danger that the oil falls below the lower limit level during operation and the oil does not run around the bearing, and a highly reliable gas compression / expansion device can be obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram of a Stirling refrigerator showing an example of an embodiment of the present invention.

FIG. 2 is a detailed cross-sectional view of a driving chamber portion of FIG.

FIG. 3 is a cross-sectional view of the drive chamber portion of FIG. 1 as viewed in the axial direction of a crankshaft.

FIG. 4 is a flowchart of an oil control operation in the oil control device of FIG. 1;

FIG. 5 is a detailed cross-sectional view showing another example of the drive chamber portion of FIG.

FIG. 6 is a flowchart of an oil control operation of the oil control device of FIG. 5;

[Explanation of symbols]

 21, 41 Valve 23 Pump 22, 24, 42 Oil piping 25 Oil tank 26 Oil control device 32 Crankshaft 36 Balancer 37 Oil passage 38 Oil reservoir 39 Oil splasher 43, 44, 45 Oil detector

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F25B 9/14 510 F04B 39/02

Claims (4)

(57) [Claims] 1. A cylinder chamber in which a piston or a displacer reciprocates, and a drive chamber in which a crank mechanism connected to the piston or the displacer via a rod is stored together with oil. A gas compression / expansion device having a mechanism for supplying oil, which is partitioned by a partition wall that penetrates and accumulates in the drive chamber with the rotation of the crank mechanism to each bearing of the crank mechanism, comprising: an oil having a valve. An oil tank connected to the drive chamber via a pipe and an oil pipe having a pump, for supplying and recovering oil to the drive chamber, and for supplying oil from the oil tank at an initial stage of operation to supply oil in the drive chamber. The oil level is raised and the oil is collected in the oil tank during stable operation, Gas compression and expansion device is characterized in that an oil control device to lower the level. 2. A first oil level detector for detecting an oil level at which the balancer and the oil splasher are sufficiently immersed, and a second oil level for detecting an oil level at which only the oil splasher is immersed, in the drive chamber. The crank mechanism includes a crankshaft rotatably driven by a drive source, a connecting rod having one end connected to the crankshaft, and a cross connected to the other end of the connecting rod. A guide, a balancer connected to the crankshaft, an oil splasher connected to the crankshaft to scrape oil accumulated on the bottom surface as the crankshaft rotates, and an oil scraped by the oil splasher Oil reservoir for storing oil in the crankshaft And an oil passage configured to supply oil from the oil reservoir to each bearing of a crank mechanism. The oil control device controls the pump and the valve, so that the driving chamber is started before the start of operation. Means for controlling the oil in the drive chamber to the oil level detected by the first oil level detector, and means for controlling the oil in the drive chamber to the oil level detected by the second oil level detector during stable operation. The gas compression / expansion device according to claim 1, wherein 3. The crank mechanism includes a crankshaft that is rotationally driven by a driving source, a connecting rod having one end connected to the crankshaft, and a cross guide connected to the other end of the connecting rod. A balancer connected to the crankshaft, an oil splasher connected to the crankshaft for scraping oil accumulated on the bottom surface as the crankshaft rotates, and an oil for storing oil scraped by the oil splasher A reservoir, and an oil passage formed inside the crankshaft and supplying oil from the oil reservoir to each bearing of the crank mechanism. The oil control device operates the valve for a first predetermined time from the start of operation. Open the oil in the drive chamber to the balancer and Means for controlling the oil level so that the oil splasher is sufficiently immersed, and further driving the pump for a third predetermined time after the lapse of a second predetermined time to control the oil in the drive chamber to an oil level at which only the oil splasher is immersed. 2. The gas compression / expansion apparatus according to claim 1, further comprising: means for driving the pump for a fourth predetermined time after the operation is completed, and returning all oil in the drive chamber to the oil tank. 4. The control device further comprises: a lower limit level detecting means for detecting that the oil level in the drive chamber has reached a lower limit level; and means for forcibly opening the valve for a predetermined time by the detecting means. The gas compression / expansion device according to claim 2, wherein the gas compression / expansion device is provided.