Information
-
Patent Grant
-
6196331
-
Patent Number
6,196,331
-
Date Filed
Friday, April 23, 199925 years ago
-
Date Issued
Tuesday, March 6, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Morgan, Lewis & Bockius LLP
-
CPC
-
US Classifications
Field of Search
US
- 173 169
- 173 DIG 2
- 173 218
- 173 219
- 173 168
- 227 130
- 181 230
- 181 211
-
International Classifications
-
Abstract
An air supply and exhaust system comprising a pneumatic tool, an air supply source, an exhaust apparatus, and at least one double-pipeline air hose. The exhaust apparatus includes a filter through which exhaust from the pneumatic tool passes and is provided apart from the pneumatic tool. The double-pipeline air hose includes two pipelines and connects the pneumatic tool and the air supply source, wherein one of the pipeline is for air supply to the pneumatic tool and the other of pipeline is for exhaust from the pneumatic tool.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an exhaust system especially for a tool driven by pneumatic pressure which causes exhaust discharged not from the tool but from the driving air supply source. More specifically, this invention relates to air supply and an exhaust system for pneumatic tools and particularly to an air supply and exhaust system which does not only reduce exhaust noise of a pneumatic tool but prevent the dust scattered by an exhaust air flow from scattering.
2. Description of the Related Art
Tools driven by pneumatic pressure, hereinafter simply called as pneumatic tools or tools, are normally arranged so that the compressed air used to drive the tools is discharged from exhaust ports into the atmosphere. However, the exhaust contains oil content and dust such as sealant dust discharged from the tool and it is undesirable that the oil content and dust are discharged into the atmosphere in view of the preservation of the environment. Moreover, because in these kind of tools, especially nailing machines, compressed air used to drive striking pistons is rapidly discharged from exhaust ports, expansion of compressed air, generation of whirling flow cause and the like cause noises. In addition, exhaust flows of compressed air blow around and diffuse dust and the like.
In view of the above, conventionally, filters are installed in the exhaust ports of the pneumatic tools so as to remove oil content, sealant dust and the like and to reduce noises by suppressing the rapid expansion of exhaust air.
However, such an arrangement for exhausting air through a filter as mentioned above may only result in decreasing output power of the tool if the flow rate of exhaust air is suppressed by the filter. Therefore, control of the flow rate of exhaust air needs to be eased, but sufficient noise reduction is not achieved.
Increasing the area of the opening of such a filter can be reasoned to cope with the problem mentioned above. This may achieve effect of the noise reduction without lowering the performance of the tool. However, the problem is that the shape and weight of the tool tend to increase, and this will result in reducing the workability.
In another conventional system for a pneumatic tool, the exhaust air is guided through an exhaust hose other than a supply hose so as to exhaust air from the tool. Then, the exhaust air is emitted into the atmosphere through an exhaust purifier having a built-in filter for soundproofing and dust-removing which is provided in the end portion of the exhaust hose.
However, in the conventional systems, two hoses have to be connected to the tool, so it results in spoiling the workability because the steering of the tool and the like become troublesome. Moreover, the laborious task of handling the tool ensues because it is necessitated to not only install the exhaust purifier separately but also move a compressed air supply source such as a compressor and the exhaust purifier when the work place is changed.
Tools such as nailing and staple driving machines driven by pneumatic pressure are constructed so that an exhaust port is provided in the head portion of a housing incorporating a pneumatic cylinder for driving a driver. The tools are also constructed so that a piston returns to a standby position by discharging pressurized air in the back of the piston from the exhaust port into the atmosphere after a nail or a staple is driven in. Therefore, the sound pressure felt by an operator is high because the pressurized air is discharged in the proximity of the operator holding the pneumatic tool. This results in accelerating operator's tired feeling to the extent that cannot be neglected. There are other problems arising from deteriorating working environment such as dust, sawdust and the like are blown up by the air flow jetted out of the exhaust port.
In order to solve the foregoing problems, there has been proposed an arrangement in which a pipe joint between a pneumatic tool and an air hose is built in the form of a coaxial double pipe comprising a center passage as an air supply passage and an outer passage as an exhaust passage surrounding the center passage (Japanese Utility Model Application Laid-open Sho. 50-27608).
In the case of the pipe joint mentioned above, pressurized air is supplied from an air compressor through the center passage of the pipe joint to the air chamber of the pneumatic tool, and exhaust is discharged through the outer passage after the air is used to drive an air cylinder. In other words, the air hose connected through the pipe joint to the pneumatic tool has of coaxial double tubular construction. That is, an outer hose is provided on the outer periphery of an air supply hose up to certain length from the pipe joint, and the end portion of the outer hose is left open as the outer hose ends in the middle of the coaxial air hose. Consequently, the exhaust air after driving the pneumatic cylinder is discharged into the atmosphere from the open end portion of the outer hose through the outer passage of the pipe joint and the outer hose of the coaxial air hose.
When the pipe joint and the coaxial air hose are employed, an exhaust port is placed away from an operator by the coaxial air hose with the effect of reducing the noise felt by the operator and preventing dust and the like from being blown up against the face of the operator. However, the absolute volume of the exhaust sound even in this case is not much different from one in the type in which the air is directly exhausted from the pneumatic tool since this case is less effective in terms of reducing the exhaust sound. On the contrary, when the coaxial air hose is moved around on the floor surface, the amount of dust and the like scattered may become greater than the amount of dust and the like directly exhausted from the pneumatic tool because the exhaust from the exhaust port in the end portion of the outer hose is in contact with the floor surface.
SUMMARY OF THE INVENTION
In order to solve the foregoing problems, as a first aspect of the invention, an object of the present invention is to provide an exhaust processing system for a pneumatic tool which can sufficiently reduces noises and prevents dust from blowing up without decreasing an output available from the pneumatic tool. As well as the above-mentioned object, it is also an object to provide an exhaust processing system for a pneumatic tool which is excellent in workability and handling convenience.
In addition, as a second aspect of the invention, an object of the present invention is to solve the foregoing technical problems by reducing the absolute volume of exhaust sound and the flow velocity of exhaust air flow to suppress noise and prevent dust and the like from scattering as much as possible.
The above object of the first aspect can be attained by an air supply and exhaust system comprising a pneumatic tool, an air supply source, an exhaust apparatus, and at least one double-pipeline air hose. The exhaust apparatus includes a filter through which exhaust from the pneumatic tool passes and is provided apart from the pneumatic tool. The double-pipeline air hose includes two pipelines and connects the pneumatic tool and the air supply source, wherein one of the pipeline is for air supply to the pneumatic tool and the other of pipeline is for exhaust from the pneumatic tool.
Preferably, the exhaust apparatus is fitted on the air supply source.
It is more preferable that the air supply and exhaust system further comprises an auxiliary tank fitted between the a pneumatic tool and an air supply source. More preferably, the exhaust apparatus is fitted on the auxiliary tank.
The above object of the second aspect can be attained by an air supply and exhaust system comprising a pneumatic tool, an air supply source, a silencer, and at least one double-pipeline air hose. The silencer includes a sound-absorbent chamber. The double-pipeline air hose includes two pipelines and connects two of the pneumatic tool, the air supply source, and the silencer, wherein one of the pipeline is for air supply to the pneumatic tool and the other of pipeline is for exhaust from the pneumatic tool.
It is preferable that the sound-absorbent chamber includes a sound-absorbent material, and the sound-absorbent material is made of felt.
More preferably, the air supply and exhaust system further comprises at least one coaxial pipe joint which includes two pipelines and connects the double-pipeline air hose and one of the pneumatic tool, the air supply source, and the silencer.
It is more preferable that the air supply and exhaust system further comprises at least one single pipe joint which includes one pipeline and connects the double-pipeline air hose and one of the air supply source and the silencer.
It is also preferable that the air supply and exhaust system further comprises a single-pipeline air hose which includes one pipeline and connect the air supply source and the silencer, wherein the double-pipeline air hose connect the pneumatic tool and the silencer.
More preferably, the air supply and exhaust system further comprises a baffle plate against which exhaust flow hits in an exhaust passage from the pneumatic tool to the sound-absorbent chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is an overall diagram of an exhaust system for a tool driven by pneumatic pressure according to a first embodiment of the present invention.
FIG. 2
is a diagram briefly explaining the principal part of the exhaust system.
FIG. 3
is a block diagram of an air exhaust system for a pneumatic tool according to a second embodiment of the present invention.
FIG. 4
is a sectional view of a silencer.
FIG. 5
is a sectional view of a pneumatic nailing machine.
FIG. 6
is a sectional view of another embodiment of the silencer.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1
to
2
show a first embodiment of the present invention. In
FIG. 1
, reference numeral
1
,
2
a
and
2
b
respectively denote a pneumatic tool (a nailing machine in FIG.
1
), an auxiliary tank and an air compressor. Driving air from the air compressor
2
b
is stored in the auxiliary tank
2
a
through an air hose
3
before being supplied to a pneumatic tool
1
through an air hose
4
. The driving air for the pneumatic tool
1
is directly supplied from the auxiliary tank
2
a
and when air pressure in the auxiliary tank
2
a
lowers, the air pressure in the auxiliary tank
2
a
is boosted by the air compressor
2
b.
Therefore, the auxiliary tank
2
a
and the air compressor
2
b
are air supply sources.
A supply port
6
for supplying the driving air and a discharge port
7
for discharging the air are arranged at the end of the grip of the tool
1
in a way adjacent to each other.
The pneumatic tool
1
and the auxiliary tank
2
a
are coupled by a double hose
4
. As shown in
FIG. 2
, the double hose
4
is so structured as to incorporate an outer pipeline
4
b
placed in the outer peripheral portion of an inner pipeline
4
a
disposed in the central portion of the hose
4
, the outer and inner pipelines
4
b
and
4
a
being coaxial. Both ends of the inner pipeline
4
a
are each connected to the discharge port
5
of the auxiliary tank
2
a
and to the supply port
6
of the pneumatic tool
1
, whereas both ends of the outer pipeline
4
b
are each connected to the discharge port
7
of the pneumatic tool
1
and to an exhaust system
8
provided in the auxiliary tank
2
a.
Consequently, the driving air from the auxiliary tank
2
a
is passed through the inner pipeline
4
a
before being supplied to the pneumatic tool
1
. The exhaust air that has been used to drive the pneumatic tool
1
is passed through the outer pipeline
4
b
and guided opposite to the direction of supplying the air to the inner pipeline
4
a
before being discharged through the exhaust unit
8
of the auxiliary tank
2
a.
An exhaust chamber
9
is formed in the exhaust system
8
, and an exhaust opening
10
having a large area is formed in the exhaust chamber
9
. Inside the exhaust opening
10
, a filter
11
being installed.
In the structure mentioned above, the tool
1
is driven by the driving air supplied from the auxiliary tank
2
a
through the inner pipeline
4
a
of the air hose so as to do nailing work first. Then the driving air is expanded while it is being passed through the exhaust system
8
of the auxiliary tank
2
a
after being passed through the outer pipeline
4
b
of the double hose
4
from the head portion of the tool
1
. When the expanded air is discharged from the exhaust opening
10
, the flow velocity of the exhaust air is suppressed by the filter
11
and dust in the exhaust air is removed; therefore, the driving air is purified before being discharged.
As set forth above, the pneumatic tool
1
is operated like an ordinary conventional pneumatic tool to supply the driving air by means of one single air hose for guiding the exhaust air up to the exhaust system
8
provided in the auxiliary tank
2
a.
Hence, the workability will not be spoiled as the pneumatic tool
1
can freely be steered.
Since the filter
11
for use in emitting the air into the atmosphere is provided for the exhaust system
8
incorporated into the auxiliary tank
2
a
of a compressed air supply source, it is only needed to move the auxiliary tank
2
a
when the work place is changed without necessitating moving the exhaust system
8
separately. It means that required labor is not worse compared with an exhaust processing system which use one hose with a conventional arrangement, and handling of the system is not troublesome.
Since a large opening area can be provided for the exhaust system
8
in order to sufficiently ease the restriction imposed on the flow rate of the exhaust air, it is possible to efficiently prevent noises arising from the emission of exhaust from the pneumatic tool
1
and also prevent dust from being blown up. Any reason causing the output power of the pneumatic tool
1
can thus be eliminated. As the exhaust system
8
is unnecessary on the side of the pneumatic tool
1
; moreover, the tools
1
can be made smaller and lighter to the extent that the exhaust system
8
is unnecessary.
The structure of the air hose used to connect the pneumatic tool
1
and the auxiliary tank
2
a
need not be a coaxial double structure but may be a structure in which two parallel pipelines (two air hoses), for example, are formed into one.
Furthermore, the exhaust system
8
need not be limited to which is provided for the auxiliary tank
2
a
but may be such that the exhaust system
8
is mounted in the air compressor
2
b
so as to exhaust air therefrom.
A second embodiment of the present invention will now be described with reference to
FIGS. 3
to
6
.
FIG. 3
is a block diagram of an air supply and exhaust system for a pneumatic tool, wherein reference numeral
101
,
102
and
103
respectively denote an air compressor, a silencer and a pneumatic nailing machine. The air compressor
101
and the silencer
102
are connected by an air hose
104
, and the silencer
102
and the pneumatic nailing machine
103
are connected by a coaxial air hose
105
. The high-pressure air sent out by the air compressor
101
is supplied from the air hose
104
to the pneumatic nailing machine
103
through the relay passage of the silencer
102
and the center hose of the coaxial air hose
105
, and exhaust air in the pneumatic nailing machine
103
is discharged into the atmosphere from the silencer
102
through the outer hose of the coaxial air hose
105
.
FIG. 4
shows the silencer
102
. The silencer
102
includes an inner tube
106
as a straight pipe. In one end portion (on the left-hand side of the silencer
102
in
FIG. 3
) of an inner tube
106
, a small-diameter portion
106
a
is formed. In the other end of thereof, a flange
106
b
is provided, and the flange
106
b
includes a vent hole. On the small-diameter portion
106
a
and the flange
106
b,
end plates
107
and
108
are respectively mounted. A cylindrical outer cover
109
surrounds the inner tube
106
and is held between the two end plates
107
and
108
. In order to fix the cylindrical outer cover
109
, stay bolts
110
pass through a plurality of holes provided in the two end plates
107
and
108
and are tightened with nuts
111
at both ends of each stay bolts
110
. The outer cover
109
is provided with a number of exhaust holes (not shown) and a sound-absorbent material
112
, such as felt and the like, is filled in between the outer cover
109
and the stay bolts
110
.
A socket
113
(hereinafter called the coaxial socket) for the coaxial double pipe joint is screwed into one end portion of the flange
106
b
of the inner tube
106
, whereas a plug
114
for an ordinary single pipe joint is screwed into the other end portion of the silencer
102
. The center passage
113
a
of the coaxial socket
113
communicates with the center passage
114
a
of the plug
114
through the inner passage
106
c
of the inner tube
106
, and the outer passage
113
b
of the coaxial socket
113
communicates with the atmosphere through the vent hole
106
d
of the flange
106
b
on the inner tube
106
and the exhaust hole of the outer cover
109
.
The coaxial plug
115
of the coaxial air hose
105
is connected to the coaxial socket
113
, and a coaxial socket at the other end of the coaxial air hose
105
is connected to the coaxial plug of the pneumatic nailing machine
103
. Further, the socket (not shown) of the air hose
104
is connected to the plug
114
, and a plug at the other end of the air hose
104
is connected to the socket of the air compressor.
FIG. 5
shows the pneumatic nailing machine
103
. The coaxial plug
115
is fitted to the end portion of a grip portion
116
. The center passage
115
a
of the coaxial plug
115
communicates with an air chamber
117
in the grip portion
116
and the outer passage
115
b
of the coaxial plug
115
communicates with an exhaust port
120
on a head side of a pneumatic cylinder
119
through an exhaust pipeline
118
passing through the grip portion
116
. The pressurized air sent out by the air compressor
101
is supplied to the air chamber
117
through the air hose
104
, the inner passage of the silencer
102
and the center hose
105
a
of the coaxial air hose
105
.
As the construction and operating principle of the pneumatic nailing machine
103
are well known, the description thereof will be described briefly. When a trigger lever
121
is pulled, pilot pressure acting on the surface of the head valve
122
of the pneumatic cylinder
119
is discharged and the head valve
122
moves up from the descent position shown in
FIG. 5
, thus causing the pressurized air to flow into the air chamber on the head side of the pneumatic cylinder
119
from the air chamber
117
. Consequently, a piston
123
and a driver
124
descends rapidly within the cylinder and the driver
124
strikes against a nail in a nose portion
125
and drives the nail into lumber and so on.
When the trigger lever
121
is released after the driving operation, the pilot pressure is applied onto the surface of the head valve
122
. As the head valve
122
is descending by the pilot pressure, the communication of the air chamber
117
with the pneumatic cylinder
119
is cut off, which results in communicating a head-side exhaust port
120
with the exhaust pipeline
118
. Accordingly, the pressurized air in the head-side air chamber is first passed through the outer hose
105
b
of the coaxial air hose
105
from the exhaust pipeline
118
, then through the outer passage
113
b
of the coaxial socket
113
of the silencer
102
and subjected to sound reduction in the silencer chamber before being discharged into the atmosphere through the sound-absorbent material
112
and the outer cover
109
.
Thus, the absolute volume of exhaust sound, particularly the exhaust sound that an operator can hear is significantly reduced because the exhaust air of the pneumatic tool
103
is discharged through the silencer
102
in a place away from an operator. Moreover, dust and the like on the floor are less scattered because the flow velocity of exhaust air flow is reduced even when the silencer
102
is placed on the floor, and dust and the like can be prevented from being scattered further if the silencer is placed in a place where dust and the like are less accumulated or in a position higher than the floor surface.
FIG. 6
shows another embodiment of the silencer according to the present invention, wherein a silencer
131
is arranged so that the interior of an outer cover
135
is divided into two chambers by inserting a cup-type baffle plate
134
between end plates
132
and
133
. The baffle plate
134
is used to trap misty lubricating oil drops contained in the exhaust air of the pneumatic nailing machine, wherein the center hole of the baffle plate
134
is provided in a small-diameter portion
136
a
formed in an inner tube
136
, and the edge face of a cup portion
134
a
is kept in contact with the inner side of the end plate
133
on the side of the coaxial socket
113
and fixedly held between the inner tube
136
and the end plate
133
.
A plurality of vent holes
134
b
are formed in the baffle plate
134
, and each stay bolt
137
for coupling the end plates
132
and
133
on both sides is passed through the vent hole
134
a.
The exhaust air flow that has flowed between the end plate
133
and the baffle plate
134
from the outer passage
113
b
of the coaxial socket
113
strikes against the baffle plate
134
, so that the misty oil drops contained in the exhaust air flow adhere to the baffle plate
134
. The air, which the most oil drops are deprived, is passed through a sound-absorbent material
138
from the vent hole
134
b
of the baffle plate
134
before being released into the atmosphere from the exhaust hole of the outer cover
135
. Therefore, the oil drops are not scattered around and the surrounding areas are prevented from being contaminated with the effect of prolonging the life of the pneumatic tool as the sound-absorbent material
138
is less soiled and clogged with dust.
The present invention is not limited to the embodiment stated above but may be modified variously in the technical scope of the invention. Needless to say, such modifications are subject to this invention.
As set forth above, the exhaust sound is reduced. Particularly, the exhaust sound near the operator is extremely decreased since the exhaust air of the pneumatic tool in the air supply and exhaust system according to the present invention is guided through the coaxial air hose to the silencer positioned away from the operator before being discharged. Moreover, dust and the like on the floor are least scattered because the flow velocity of exhaust air flow is reduced by the silencer. Thus, any problem arising from noise and sanitation can be solved, whereby the present invention can contribute to improvement in working environment.
The present invention is based on Japanese Patent Application Nos. Hei. 10-115449 and Hei. 10-261368, which are incorporated herein by reference.
Claims
- 1. An air supply and exhaust system comprising:a pneumatic tool; an air supply source; an exhaust apparatus including a filter through which exhaust from said pneumatic tool passes, said exhaust apparatus being fitted onto said air supply source and being provided apart from said pneumatic tool; and at least one double-pipeline air hose which includes two coaxial pipelines and connects said pneumatic tool to said air supply source, wherein one of said pipelines, supplies air to said pneumatic tool from said air supply source and the other pipeline exhausts air from said pneumatic tool to said exhaust apparatus.
- 2. The air supply and exhaust system according to claim 1, further comprising an auxiliary tank fitted between said pneumatic tool and said air supply source.
- 3. The air supply and exhaust system according to claim 2, wherein said exhaust apparatus is fitted on said auxiliary tank.
- 4. The air supply and exhaust system according to claim 3, further comprising:a single-pipeline air hose which includes one pipeline and connects said air supply source to said auxiliary tank, wherein said double-pipeline air hose connects said pneumatic tool to said auxiliary tank.
- 5. The air supply and exhaust system according to claim 2, further comprising at least one coaxial pipe joint which includes two pipelines and connects said double-pipeline air have to one of said pneumatic tool and said auxiliary tank.
- 6. The air supply and exhaust system according to claim 1, further comprising at least one coaxial pipe joint which includes two pipelines and connects said double-pipeline air hose to one of said pneumatic tool and said air supply source.
- 7. An air supply and exhaust system comprising:a pneumatic tool; an air supply source; a silencer fitted onto said air supply source, said silencer including a sound-absorbent chamber; and at least one double-pipeline air hose which includes two coaxial pipelines and connects said pneumatic tool to said air supply source, and said silencer, wherein one of said pipelines is for air supply from said air supply source to said pneumatic tool and the other of pipelines is for exhaust from said pneumatic tool to said silencer.
- 8. The air supply and exhaust system according to claim 7, wherein said sound-absorbent chamber includes a sound-absorbent material.
- 9. The air supply and exhaust system according to claim 8, wherein said sound-absorbent material is made of felt.
- 10. The air supply and exhaust system according to claim 7, further comprising at least one coaxial pipe joint which includes two pipelines and connects said double-pipeline air hose to one of said pneumatic tool, said air supply source, and said silencer.
- 11. The air supply and exhaust system according to claim 10, further comprising at least one single pipe joint which includes one pipeline and connects said double-pipeline air hose to one of said air supply source and said silencer.
- 12. The air supply and exhaust system according to claim 11, further comprising:a single-pipeline air hose which includes one pipeline and connect said air supply source to said silencer, wherein said double-pipeline air hose connects said pneumatic tool to said silencer.
- 13. The air supply and exhaust system according to claim 12, further comprising at least one single pipe joint which includes one pipeline and connects said double-pipeline air hose to one of said air supply source and said silencer.
- 14. The air supply and exhaust system according to claim 7, further comprising a baffle plate against which exhaust flow hits in an exhaust passage from said pneumatic tool to said sound-absorbent chamber.
- 15. The air supply and exhaust system according to claim 14, further comprising at least one coaxial pipe joint which includes two pipelines and connects said double-pipeline air hose to one of said pneumatic tool, said air supply source, and said silencer.
- 16. The air supply and exhaust system according to claim 15, further comprising:a single-pipeline air hose which includes one pipeline and connects said air supply source to said silencer, wherein said double-pipeline air hose connects said pneumatic tool to said silencer.
- 17. The air supply and exhaust system according to claim 16, further comprising at least one single pipe joint which includes one pipeline and connects said double-pipeline air hose to one of said air supply source and said silencer.
- 18. An air supply and exhaust system comprising:a pneumatic tool; an air supply source; an auxiliary tank; an exhaust apparatus including a filter through which exhaust from said pneumatic tool passes, said exhaust apparatus being fitted onto said auxiliary tank and being provided apart from said pneumatic tool; and at least one double-pipeline air hose including two coaxial pipelines for respectively supplying air from said air supply source to said pneumatic tool and for exhausting air from said pneumatic tool to said exhaust apparatus said at least one double-pipeline air hose connecting said pneumatic tool to said air supply source via said auxiliary tank.
- 19. The air supply and exhaust system according to claim 18, wherein said at least one double-pipeline air hose includes a single pipeline air hose portion connecting said air supply source with said auxiliary tank, and a double-pipeline air hose portion connecting said auxiliary tank to said pneumatic tool.
- 20. The air supply and exhaust system according to claim 18, further comprising a coaxial pipe joint for connecting said at least one double-pipeline air hose to one of said pneumatic tool and said auxiliary tank.
Priority Claims (2)
Number |
Date |
Country |
Kind |
10-115449 |
Apr 1998 |
JP |
|
10-261368 |
Sep 1998 |
JP |
|
US Referenced Citations (8)
Foreign Referenced Citations (1)
Number |
Date |
Country |
50-27608 |
Aug 1975 |
JP |