JP3286483B2 - Free piston Vilmier cycle engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a free-piston Vilmier cycle engine (Fre
e Piston Vuillermiercycle Machine).

[0002]

2. Description of the Related Art FIG. 3 is a cross-sectional view of a main part of a conventional free-piston-type Vilmier cycle engine (hereinafter may be abbreviated as a VM engine), and its structure and operation will be described. In the figure, a high-temperature displacer 1 has a stepped rod in which a rod 2 having a diameter a and a rod 3 having a diameter b are arranged in series, and the end of the rod 3 is forcibly moved by a vibrator (not shown). Is driven up and down. On the other hand, on the outside of the cylindrical sleeves 4a and 4b, the high-temperature-side high-temperature part heat exchanger 5, the high-temperature side regenerator 6, the high-temperature medium-temperature part heat exchanger 7,
A low-temperature medium-temperature heat exchanger 8, a low-temperature regenerator 9, and a low-temperature low-temperature heat exchanger 10 are provided. The high-temperature medium-temperature heat exchanger 7 and the low-temperature medium-temperature heat exchanger 8 are ring-shaped. They are integrated via the part 11. Further, outside the high temperature side regenerator 6, the high temperature side middle temperature part heat exchanger 7, and the low temperature side middle temperature part heat exchanger 8, a high temperature side cylindrical shell 12, and a medium temperature side cylindrical shell 13a, 13b are arranged, respectively. A low-temperature cylindrical shell 14 is provided outside the low-temperature side regenerator 9 and the low-temperature side low-temperature part heat exchanger 10 to be isolated from the outside.

An electric heater 15 is provided at the head of the cylindrical shell 12 on the high-temperature side. Heat is taken out from the high-temperature medium-temperature heat exchanger 7 and the low-temperature medium-temperature heat exchanger 8 for heating, and the low-temperature medium heat exchanger 8 is used for cooling. Cold heat is provided from the side low-temperature section heat exchanger 10. Water is arranged outside the respective heat exchangers as a transport medium. In addition, a vibrator (not shown) is connected to a lower portion of the rod 3, and is used for vibrating the high-temperature displacer 1 for starting and steady operation. Here, the electric heater 1
The working water such as helium in the high temperature working space 16 and the medium temperature working space 17 heated by 5 heats the outer water through the high temperature side middle temperature part heat exchanger 7, while the low temperature working space 18 and the medium temperature working The working gas in the space 17 heats the outer water through the low-temperature intermediate-temperature heat exchanger 8 and removes heat from the outer water through the low-temperature low-temperature heat exchanger 10. At this time, the up-and-down movement of the high-temperature displacer 1 causes the working gas to flow between the high-temperature working space 16 and the medium-temperature working space 17, thereby causing the high-temperature high-temperature section heat exchanger 5, high-temperature side regenerator 6, and high-temperature medium-temperature section heat exchanger. Alternate through 7. The vertical movement of the low-temperature displacer 19 that divides the medium-temperature operation space 17 and the low-temperature operation space 18 causes the working gas to flow between the low-temperature operation space 18 and the medium-temperature operation space 17 through the low-temperature low-temperature part heat exchanger 10, the low-temperature regenerator 9, and Alternating through low temperature side middle temperature heat exchanger 8. At that time, a change in the ratio between the high-temperature working gas and the low-temperature working gas causes pressure fluctuations in the entire working chamber. Displacer piston rod 2 of diameter a, low temperature area difference of both end faces of the low-temperature displacer 19 that by the difference in b <br/>
The difference between the pressure in the displacer 19 and the pressure in the working chamber acts
As a result, an exciting force is generated, and the low-temperature displacer 19 operates so as to maintain a certain phase difference from the high-temperature displacer 1. At this time, the temperature of each working space is kept constant by the heat storage action of each of the regenerators 6 and 9. The output of the VM engine is used for heating and cooling using the heat release and absorption of the heat exchangers 5, 7, 8, and 10.

[0004] As a technical document on a VM engine, "D
evelopment of a Free PistonVuilleumier Machine
for Cooling Purposes ”(ISEC-91060 P.15) and“ Basic Research on Free-Piston Villemy Cycle Heat Pump ”by the present inventors (Presentation at the 71st Ordinary General Meeting of the Japan Society of Mechanical Engineers). The former includes the V which is the object of the present invention.
A test machine with the same structure as the M engine was introduced, and the latter
A VM heat pump developed by the authors is introduced.

[0005]

In the conventional construction as described above, the vibrator section environment mounted on the lower portion of the rod 3 is at a steady pressure, and a box is formed by using the vibrator housing section as a buffer chamber. In this case, the pressure of the gas sealed in the buffer chamber is usually set to be equal to the average pressure of the working gas in each of the working spaces described above, and the influence of the pressure in the buffer chamber on the improvement of the operation of the high-temperature displacer and the low-temperature displacer is described. Was not considered, and the consequent improvement in engine performance was not clear. An object of the present invention is to solve the above-mentioned problems (problems) of the conventional engine and to provide a free-piston-type Virmier cycle engine having higher performance than the conventional engine without using a special configuration that makes it expensive. Aim.

[0006]

SUMMARY OF THE INVENTION A free-piston Vilmier cycle engine (VM engine) according to the present invention uses an average pressure in a buffer chamber provided with driving means for exciting a rod connected to a high-temperature displacer. The above problem is solved by setting the pressure lower than the working gas average pressure.

[0007]

[Action] In VM engine of the present invention, since the set lower than the working gas mean pressure in the working space an average pressure of the buffer chamber provided with a driving means for driving the rod for connecting the high-temperature displacer, the pressure difference rod Made as the excitation force of
Use, pumping calorie, exhalation calorie increase,
The amount of work and the amount of exchanged heat increase, and the performance as a heat pump, that is, both the cooling capacity and the heating capacity, increase.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a cross section of a main part of a VM engine constructed according to the present invention. In FIG. 1, components corresponding to those of the conventional engine are denoted by the same reference numerals as those in FIG. 3, and detailed description thereof is omitted. I do. In FIG. 1, a lower end of a rod 3 is coupled to a movable portion 21 of a linear motor which is a driving mechanism for vibration in a buffer chamber 20, and a fixed portion 22 of the linear motor is fixed to a predetermined position in the buffer chamber. I have. A high-temperature displacer mechanical spring 23 is connected to a lower portion of the rod 3, and the high-temperature displacer mechanical spring 23 is fixed to a ceiling surface of the buffer chamber 20. In the figure, reference numeral 24 denotes a seal for preventing gas leakage from the rod portion, and reference numeral 25 denotes a ring-shaped seal for preventing gas leakage from the buffer chamber, which keeps the inside of the buffer chamber 20 confidential. Reference numeral 27 denotes an auxiliary mechanical spring for a low-temperature displacer. At the time of assembling the VM engine, the working gas is sealed in the buffer chamber 20 so as to have a predetermined pressure lower than the average pressure of the working gas in the working space during operation. In order to enclose a working gas at a predetermined pressure in the buffer chamber, a gas supply port provided with an on-off valve at an appropriate location corresponding to the shape / configuration of the buffer chamber is provided, and the gas pressure in the buffer chamber is adjusted at appropriate times. It may be determined.

In the VM engine of the present invention, the average pressure in the buffer chamber provided with the driving means for driving the rod connected to the high-temperature displacer is set lower than the average pressure of the working gas in the working space as described above. When the VM engine is driven, the gas pressure in the enclosed buffer chamber is increased by a rod.
The operation of the high temperature displacer and the low temperature displacer is made more ideal by acting on the driving of the third . Thus, the amount of heat exchanged with the combined load is increased. In FIG. 2, the horizontal axis shows the change of the pressure P _B in the buffer chamber 20 with respect to the average pressure P _mean of the working gas in each working space, and the vertical axis shows this P _B / P _mean.
Heat capacity Q _C (kW) corresponding to the change of
Shows the calculated values Example conducted in the structure of a given VM engine for and discharging heat Q _R (kW). As shown in the figure, increases the amount of heat Q _C and spit heat Q _R assembling a buffer chamber pressure P _B becomes lower than the working gas mean pressure P _mean in the working space are both workload increases amount of heat exchange in an increase Thus, it is shown that the performance as a heat pump is improved, and both the cooling capacity and the heating capacity are increased.

The above-described embodiment is an example for realizing the technical idea of the present invention, and a buffer room having a structure other than that shown in the present embodiment is also provided for a VM engine. It is only necessary to set the gas pressure to a predetermined pressure lower than the average pressure of the working gas in the working space, and it is natural that the gas pressure setting means in the buffer chamber may be appropriately configured corresponding to the structure and the like of the buffer chamber. It is. For example, in the structural example shown in FIG. 1, the buffer chamber is described as being later assembled to the main body of the VM engine. However, since the pressure difference between the buffer chamber and the VM engine is low, the load of each gas seal is reduced. It is also possible to use a sealing material with reduced durability and cost and to use a maintenance-free configuration to include the buffer chamber in the VM engine to have a closed structure.

[0011]

As described above, in the free-piston Vilmier cycle engine (VM engine) according to the present invention, the pressure in the buffer chamber is lower than the average pressure of the working gas in the working space. Increased together. Therefore, the amount of work increases, the amount of exchange heat increases, the performance as a heat pump improves, and there is an excellent effect that both the cooling capacity and the heating capacity increase.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing a main configuration of a free-piston Vilmier cycle engine according to the present invention.

FIG. 2 is a characteristic diagram illustrating the operation of the present invention.

FIG. 3 is a vertical sectional front view showing a main configuration of a conventional free-piston Vilmier cycle engine.

[Explanation of symbols]

 1: High temperature displacer 5: High temperature side high temperature part heat exchanger 6: High temperature side regenerator 7: High temperature side medium temperature part heat exchanger 8: Low temperature side medium temperature part heat exchanger 9: Low temperature side regenerator 10: Low temperature side low temperature part heat Exchanger 12: High temperature side cylindrical shell 13a, 13b: Medium temperature side cylindrical shell 14: Low temperature side cylindrical shell 15: Electric heater 16: High temperature working space 17: Medium temperature working space 18: Low temperature working space 19: Low temperature displacer 20: Buffer chamber 24, 25: Seal

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-61761 (JP, A) JP-A-63-243439 (JP, A) JP-A-64-87852 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F25B 9/14 510 F02G 1/05

Claims (1)

(57) [Claims] 1. A high temperature side high temperature section heat exchanger, a high temperature side regenerator,
In a free-piston Villemy cycle engine having a high-temperature medium-temperature section heat exchanger, a low-temperature medium-temperature section heat exchanger, a low-temperature regenerator and a low-temperature low-temperature section heat exchanger, and further including a high-temperature displacer and a low-temperature displacer, A free-piston Vilmier cycle engine wherein an average pressure in a buffer chamber provided with a driving means for exciting a rod connected to a displacer is set lower than an average pressure of a working gas in a working space.