Pulse nozzle

A pulse nozzle of a reaction apparatus which obtains a very low temperature by expanding high-pressure and normal-temperature gas in heat insulation manner includes a fixed slit member disposed at an inlet of the nozzle and having a plurality of slit openings, a movable slit member having similar slit openings disposed along the fixed slit member, and two piezoelectric-crystal elements driven by an external pulse signal to slidably move the movable slit member with respect to the fixed slit member repeatedly to thereby open and close a flow of gas in the pulse manner. A plurality of the pulse nozzles are disposed in parallel to increase the capacity of the pulse nozzle.

FIELD OF THE INVENTION AND RELATED ART STATEMENT 
The present invention relates to a pulse nozzle, and more particularly to a 
nozzle for improving the reaction efficiency and increasing the capacity 
of a reaction apparatus for generating a chemical reaction and a physical 
reaction at a very low temperature. 
Until a recent date, it has been desired to develop a pulse nozzle more 
suitable for a reaction apparatus capable of obtaining a very low 
temperature by expanding high-pressure and normal-temperature gas in heat 
insulation manner. 
Heretofore, in order to attain the nozzle of this kind, an solenoid 
controlled valve is used to feed fluid intermittently. 
However, there is a problem that a repetition frequency of the intermittent 
feeding of the fluid by the solenoid controlled valve can not be increased 
since an electromagnetic driving portion of the solenoid controlled valve 
is broken by heat when the repetition frequency is increased to 10 Hz or 
more. 
It is necessary to make large the solenoid controlled valve to process a 
large amount of fluid in order to improve the reaction efficiency of the 
reaction apparatus. However, when the solenoid controlled valve is made 
large, there is a problem that a driving power is increased and the 
repetition frequency of the intermittent feeding of the fluid is lowered 
extremely. 
OBJECT AND SUMMARY OF THE INVENTION 
The present invention has been made in view of the above problems and it is 
an object of the present invention to solve the problems by providing a 
pulse nozzle having a structure more suitable for the reaction apparatus 
and in which the repetition frequency of the intermittent feeding is 
improved to be high. 
It is another object of the present invention to provide a pulse nozzle 
suitable for processing of a large amount of fluid without reduction of 
the repetition frequency to improve the efficiency of the reaction 
apparatus. 
In order to attain the above objects, the present invention is configured 
as described in the following (1) and (2): 
(1) The pulse nozzle of the reaction apparatus obtaining a very low 
temperature by expanding high-pressure and normal-temperature gas in heat 
insulation manner, comprises: 
a fixed slit member disposed at an inlet of the pulse nozzle and having a 
plurality of slit openings, a movable slit member disposed to be slidably 
moved with respect to the fixed slit member and having a plurality of 
similar slit openings disposed at a position coincident with that of the 
plurality of slit openings of the fixed slit member when the pulse nozzle 
is open, and two piezoelectric-crystal elements supporting both ends of 
the movable slit member, respectively, for driving to slidably move the 
movable slit member from the both ends thereof. 
The pulse nozzle is characterized in that the two piezoelectric-crystal 
elements are driven in cooperative manner in the same direction by a pulse 
signal supplied externally and when the plurality of slit openings of the 
movable slit member being slidably moved coincide with the plurality of 
slit openings of the fixed slit member, the pulse nozzle is opened while 
when the openings do not coincide the pulse nozzle is not opened. 
(2) A plurality of pulse nozzles described in (1) are characterized to be 
disposed in parallel. 
In operation of the present invention, the movable slit member is slidably 
moved by being driven by the two piezoelectric-crystal elements supporting 
both ends of the movable slit member and when the slit openings of the 
movable slit member coincide with the slit openings of the fixed slit 
member, the pulse nozzle is opened so that a flow of gas occurs. 
When the slit openings of the movable slit member is deviated from the slit 
openings of the fixed slit member and do not coincide with the slit 
openings, the pulse nozzle is closed so that the flow of gas is stopped. 
Thus, a pulse flow of gas occurs. 
Further, a plurality of the pulse nozzles are disposed in parallel and are 
operated simultaneously, so that a large amount of pulse flow of gas can 
be obtained. 
According to the pulse nozzle of the present invention, the pulse flow of 
gas having the improved intermittent feeding of gas and increased 
repetition frequency can be obtained and can be applied to the reaction 
apparatus. 
A large-sized structure of the pulse nozzle which can not be attained 
heretofore due to restriction of a driving power of the 
piezoelectric-crystal element operating as a drive source of the movable 
slit member can be attained and can be applied to the processing of a 
large amount of gas. 
The pulse flow of gas passes through a nozzle portion and is expanded in 
heat insulation manner to be a gas flow having a very low temperature. A 
period of generating the very low temperature gas is made coincident with 
an irradiation period of laser light for reaction to thereby be able to 
improve the reaction efficiency and increase the capacity of the reaction 
apparatus.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
Preferred embodiments of the present invention are now described in detail 
with reference to the accompanying drawings. 
[First Embodiment] 
FIGS. 1 and 2 are sectional views of a pulse nozzle 1 according to a first 
embodiment of the present invention, which is used in a reaction apparatus 
which obtains a very low temperature by expanding high-pressure and 
normal-temperature gas in heat insulation manner. 
A nozzle portion 2 of the pulse nozzle 1 includes a nozzle opening 2b 
communicating with a nozzle inlet 2a and having an inner portion being 
narrowed on the way thereof and a nozzle outlet 2c which is opened with an 
enlarged diameter. A fixed slit member 3 having a plurality of slits 
(three slits in FIG. 1) 3a formed perpendicularly to a flow of gas G and 
the nozzle opening 2b is fixedly disposed in an inlet side chamber 2d of 
the nozzle portion 2. 
A movable slit member 4 having a width of, for example, about 50 mm and 
including a plurality of slits 4a similar to the slit 3a is disposed to be 
slidably moved while the plane of the movable slit member 4 is in contact 
with the plane of the fixed slit member 3. The plurality of slits 4a are 
positioned to coincide with the plurality of slits 3a of the fixed slit 
member 3 when the pulse nozzle 1 is opened. 
Two piezoelectric-crystal elements 5 and 6 having one ends supporting both 
upper and lower sides of the movable slit member 4 to drive to be slidably 
moved the movable slit member 4 and the other ends fixedly attached to a 
fixed portion of the pulse nozzle 1 are disposed in the inlet side chamber 
2d of the nozzle portion 2. Numerals 5a, 5b and 6a, 6b denote connection 
terminal of the piezoelectric-crystal elements 5 and 6, respectively. 
Operation of the pulse nozzle 1 is now described with reference to FIG. 3. 
An external pulse generator 7 is connected through lead wires 8 to 
connection terminals 5a, 5b and 6a, 6b of the two piezoelectric-crystal 
elements 5 and 6, respectively, for slidably moving the movable slit 
member 4 of the pulse nozzle 1, so that the same pulse voltage is applied 
to drive the two piezoelectric crystal elements 5 and 6 in the same 
direction. 
The pulse nozzle 1 shown in FIG. 1 includes the piezoelectric crystal 
elements 5 and 6 which are not applied with a voltage from the pulse 
generator 7 and the piezoelectric crystal elements 5 and 6 are returned to 
the original position by the returning force thereof so that the plurality 
of slits 4a of the movable slit member 4 coincide with the plurality of 
slits 3a of the fixed slit member 3 to open the pulse nozzle 1. At this 
time, the flow of gas G is sent from the nozzle inlet 2a maintained to a 
high pressure to the nozzle outlet 2c maintained to a low pressure by a 
compressor or the like. 
As shown in FIG. 3, when the voltage from the pulse generator 7 is applied 
to the piezoelectric-crystal elements 5 and 6 through the terminals 5a, 5b 
and 6a, 6b, respectively, the piezoelectric-crystal elements 5 and 6 are 
driven in the same direction of arrow to be deflected so that the 
piezoelectric-crystal elements 5 and 6 slidably move the movable slit 
member 4 in the direction of arrow of FIG. 3. Consequently, the plurality 
of slits 4a of the movable slit member 4 do not coincide with the 
plurality of slits 3a of the fixed slit member 3, so that the pulse nozzle 
1 is closed. Accordingly, it is stopped to sent gas from nozzle inlet 2a 
to the nozzle outlet 2c. 
Accordingly, the voltage generated by the pulse generator 7 is applied to 
the piezoelectric crystal elements 5 and 6 in the pulse manner, so that 
gas can be sent from the nozzle inlet 2a to the nozzle outlet 2c 
intermittently. 
When the pulse nozzle 1 is closed, seal of the slits is made by plane 
contact of the fixed slit member 3 and the movable slit member 4. 
[Second Embodiment] 
It is necessary to make large the pulse nozzle to process a large amount of 
gas in order to improve the reaction efficiency of the reaction apparatus, 
while if the fixed slit member 3, the movable slit member 4 and the 
piezoelectric-crystal elements 5 and 6 are made large in the first 
embodiment, there is a problem that the movable slit member 4 is not 
slidably moved by a pressure of gas and the flow of gas G in the form of 
pulse does not occur. 
This is caused by the fact that since the driving force of the 
piezoelectric-crystal elements 5 and 6 used in the pulse nozzle 1 is 
limited, the driving force of the piezoelectric crystal elements 5 and 6 
is exceeded when the movable slit member 4 is made large. A factor of 
preventing or disturbing increase of the capacity of the pulse nozzle is 
that the movable slit member 4 having a size capable of being slidably 
moved by the driving force of the piezoelectric crystal elements 5 and 6 
must be used. 
FIGS. 4 and 5 show a second embodiment of the present invention which shows 
a pulse nozzle 11 in section including a plurality (five sets in this 
embodiment) of the pulse nozzles 1 of the first embodiment disposed in 
parallel in order to solve the problems in the first embodiment. 
A nozzle portion 12 of the pulse nozzle 11 includes a nozzle opening 12b 
communicating with a nozzle inlet 12a and having an inner portion being 
narrowed on the way thereof and a nozzle outlet 12c which is opened with 
an enlarged diameter. A plurality of fixed slit members (five sets in 
FIGS. 4 and 5) 13 put side by side and having a plurality of slits (three 
slits in FIG. 4) 13a arranged vertically in FIG. 5 are disposed 
perpendicularly to the flow of gas G and the nozzle opening 12b in an 
inlet side chamber 12d of the nozzle portion 12. 
As shown in FIGS. 4 and 5, a plurality (five sets in Figures) of movable 
slit members 4 having a width of about 50 mm and a plurality of pairs of 
piezoelectric-crystal elements 5 and 6 for driving to slidably move the 
movable slit members 4 with respect to the fixed slit members 13 are 
disposed in the inlet side chamber 12d of the nozzle portion 12 to be 
slidably moved to the fixed slit members 13. 
The plurality of pairs of piezoelectric-crystal elements 5 and 6 are driven 
simultaneously in the same direction by a pulse generator not shown 
connected externally. 
The same elements as those of FIGS. 1 and 2 are designated by the same 
numerals and description thereof is omitted. 
In the embodiment, the pulse nozzle 11 includes a plurality of pulse nozzle 
1 of the first embodiment disposed in parallel, while the number of the 
pulse nozzle 1 can be increased or reduced properly in accordance with a 
desired capacity of the pulse nozzle 11. 
When the number of the movable slit member 4 and the pair of 
piezoelectric-crystal elements 5, 6 is five, the overall width of the 
movable slit members 4 is five times of the width of the pulse nozzle 1 
and the capacity of the pulse nozzle 11 is also five times of the pulse 
nozzle 1 of the first embodiment. 
The present invention is not limited to the embodiment, while the present 
invention can be attained by using other means having the similar function 
and various modification and addition can be made thereto without 
departing from the scope of the present invention.