Air intake passage cleaning method and its apparatus

Information

  • Patent Grant
  • 6230359
  • Patent Number
    6,230,359
  • Date Filed
    Monday, March 29, 1999
    25 years ago
  • Date Issued
    Tuesday, May 15, 2001
    23 years ago
  • Inventors
  • Examiners
    • Stinson; Frankie L.
    Agents
    • Kojima; Moonray
Abstract
The present invention provides air intake passage cleaning method and its apparatus for cleaning the air intake passage of intake and exhaust apparatus for conditioning the air in building, ship, aircraft, automobile, train, or other room, to be used in an intake and exhaust apparatus comprising a heat exchanger, and at least one blow-out port for blowing out air conditioning air exchanged in heat by the heat exchanger, comprising supplying means for supplying a cleaning solvent, together with compressed air, to the heat exchanger side from a specific blow-out port through an air intake passage, and moving means for moving cleaning and wiping elements loaded in the air intake passage toward a specific blow-out port side, and hence relates to air intake passage cleaning method and its apparatus capable of securely cleaning and removing dirt deposits in the air intake passage and heat exchanger, and obtaining sanitary environments.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to air intake passage cleaning method and its apparatus for cleaning the air intake passage of intake and exhaust apparatus such as air conditioning passage of air conditioner for conditioning the air in, for example, building, ship, aircraft, automobile, train, or other room.




2. Description of the Prior Art




Hitherto, the air conditioner incorporates, in its housing, a heat exchanger which acts as an evaporator in cooling and a condenser in heating, and the heat exchanger and air intake passage are likely to be contaminated, and germs and molds are formed in the process of heat exchange of the indoor air containing dust, moisture, cigarette smoke or the like taken in from the air suction port provided in the housing.




When air conditioning is operated in such state, the sanitation in the room is spoiled, and the indoor environments deteriorate due to generation of offensive smell.




SUMMARY OF THE INVENTION




It is hence a primary object of the invention to present an air intake passage cleaning apparatus capable of cleaning the air intake passage and heat exchanger securely and improving the indoor environments, by comprising supplying means for supplying cleaning solvent, together with compressed air, to the heat exchanger side from the blow-out port through the air intake passage.




It is other object of the invention to present an air intake passage cleaning apparatus capable of improving the ease of cleaning operation, by disposing the above supplying means in an arbitrary blow-out port out of plural blow-out ports.




It is a different object of the invention to present an air intake passage cleaning apparatus capable of cleaning the entire region and heat exchanger securely even if the air intake passage is long in the passage length, by disposing the above supplying means in the blow-port port at the remotest position from the heat exchanger out of plural blow-out ports.




It is another object of the invention to present an air intake passage cleaning apparatus capable of cleaning the air intake passage and heat exchanger securely and improving the indoor environments, by cleaning the air intake passage by supplying compressed air and cleaning solvent from the blow-out port to the heat exchanger side through the air intake passage.




It is a further object of the invention to present an air intake passage cleaning apparatus capable of preventing the fluid after cleaning from flowing out from other blow-out port and enhancing the cleaning efficiency, by blocking other blow-out ports with a clocking member when supplying air and cleaning solvent from a specific blow-out port.




It is still other object of the invention to present an air intake passage cleaning apparatus capable of obtaining sanitary environments, by moving a cleaning and wiping element provided in the air intake passage by moving means, thereby cleaning and removing securely and cleanly the dirt depositing inside the air intake passage, for example, by the cleaning power of the cleaning solvent impregnated or adhered to the cleaning and wiping element.




It is a further different object of the invention to present an air intake passage cleaning apparatus capable of moving all cleaning and wiping elements together to the blow-out port side and cleaning and removing the dirt depositing inside the air intake passage in a short time, by blocking the other blow-out ports except for a specific blow-out port, when applying a transfer pressure supplied from the air supplying means to the cleaning and wiping elements provided in the air intake passage.




It is a still further different object of the invention to present an air intake passage cleaning apparatus capable of wiping and removing the dirt depositing inside the air intake passage by the cleaning and wiping elements, and freely changing the wiping position by the cleaning and wiping elements depending on the position and area of contamination, by towing and manipulating linear traction members linked to the cleaning and wiping elements.




Other objects of the invention will be clarified from the following description of the embodiment.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a sectional view showing an air intake passage cleaning method and its apparatus of the invention.





FIG. 2

is an essential magnified view of FIG.


1


.





FIG. 3

is a sectional view showing other embodiment of air intake passage cleaning method of the invention.





FIG. 4

is a sectional view showing a different embodiment of air intake passage cleaning method and its apparatus of the invention.





FIG. 5

is a sectional view showing a further different embodiment of air intake passage cleaning method and its apparatus of the invention.





FIG. 6

is a sectional view showing a duct cleaning method.





FIG. 7

is a sectional view showing a still different embodiment of air intake passage cleaning method and its apparatus of the invention.





FIG. 8

is a sectional view showing a mounting state of cleaning and wiping elements and traction pipes.





FIG. 9

is a sectional view showing a cleaning method by traction wires and traction pipes.





FIG. 10

is a sectional view showing a mounting state of traction wires and traction pipes.





FIG. 11

is a sectional view showing another different embodiment of air intake passage cleaning method and its apparatus of the invention.





FIG. 12

is a sectional view showing a mounting state of cleaning and wiping elements.





FIG. 13

is a sectional view showing a cleaning method by tubular cleaning and wiping elements.





FIG. 14

is a sectional view showing a mounting state of tubular cleaning and wiping elements.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring now to the drawings, embodiments of the invention are described below.




The drawings show the air conditioning passage cleaning method and its apparatus of the air conditioner as an example of the air intake passage of the intake and exhaust apparatus, and referring first to FIG.


1


. the constitution of the air conditioner is described.




The air conditioner


1


of the central air conditioning system shown in

FIG. 1

comprises a housing


2


of an indoor unit. and an air suction port


4


having a filter


3


communicates to the air suction side of the housing


2


. and a fan


5


is provided in the housing


2


.




In the downstream of the fan


5


, a heat exchanger


6


working as an evaporator when cooling and working as a condenser when heating is disposed. and a drain pan


8


having a drain pipe


7


is disposed in the lower part of the heat exchanger


6


. The heat exchanger


6


communicates and connects to an outdoor unit (not shown).




To communicate to a downstream side chamber


9


of the heat exchanger


6


, ducts


10


A,


10


B of each air conditioning area (the air conditioning area of each floor in the case of a building, the air conditioning area of each vehicle or cabin in the case of a moving structure) are provided, and plural blow-out ports


11


,


12


,


13


,


14


,


15


,


16


are opened in these ducts


10


A,


10


B.




An air intake passage cleaning apparatus in a first embodiment for cleaning thus constituted air conditioner


1


comprises, as shown in FIG.


1


and

FIG. 2

, a blowing fan as blowing means for sending compressed air A, and a solvent source


18


for supplying a cleaning solvent B by making use of the air flow by the blowing fan


17


.




In this embodiment, an arbitrary blow-out port of the plural blow-out ports


11


to


16


(preferably the blow-out port positioned at a considerably remote position from the heat exchanger


6


) or the blow-out port


16


at the remotest position from the heat exchanger


6


is provided with a detachable seal member


19


, and two joint pipes


20


,


21


are disposed in this seal member


19


.




One joint pipe


20


communicates and connects to the discharge port of the blowing fan


17


through a blowing line


22


, and other joint pipe


21


communicates and connects to the solvent source


23


through a solvent line


23


.




Herein, the cleaning solvent B may be liquid detergent, foamy (mousse) detergent (water, phosphoric acid, Softanol 70, propylene glycol monomethyl ether MFG, and others properly blended), cleaning water, or soap water, which may be used alone, or such cleaning solvent B may be mixed with solvents having other functions such as aromatic, medicine, deodorant, bactericide, fungicide and others to be used as compound.




The solvent source


18


may be of filled container type for discharging the solvent by the pressure of sealing gas, or a pump or the like may be also used for pumping out the solvent by force if the solvent discharge force is insufficient by the blowing force of the blowing fan


17


alone.




Moreover, when supplying the air A and cleaning solvent B from a specific blow-out port (for example, blow-out port


16


). a detachable blocking member


14


is provided to block the other blow-out ports


11


to


15


air-tightly. The blocking member


24


may be lid, plug, sheet, tape, packing, or other members, and these blocking members


24


close the blow-out ports


11


to


15


according to the structure of the blow-out ports


11


to


15


.




Using thus constituted air intake passage cleaning apparatus, to clean the ducts


10


A,


10


B and heat exchanger


6


of the air conditioner


1


, first the fan


5


is stopped, and then the other blow-out ports


11


to


15


are closed by the blocking members


24


.




Then, as shown in FIG.


1


and

FIG. 2

, the seal member


19


is attached to the specific blow-out port (for example, blow-out port


16


), and the cleaning solvent B is supplied, together with the compressed air A, from the two joint pipes


20


,


21


to the duct


10


B and the heat exchanger


6


through the downstream side chamber


9


as indicated by arrow in FIG.


1


.




That is, the cleaning solvent B is supplied in the opposite direction to the flowing direction of the normal air conditioning flow. In this case, since the ducts


10


B,


10


A communicate to each other, the cleaning solvent B is also supplied to the duct


10


A side.




In this way, when the cleaning solvent B is supplied from the specific blow-out port (for example, the blow-out port


16


at the position remotest from the heat exchanger


6


) to the heat exchanger


6


side, the inside of the ducts


10


B,


10


A and heat exchanger


6


can be cleaned by this cleaning solvent B. and the waste liquid after cleaning is discharged outside of the housing


2


from the drain pipe


8


through the drain pipe


7


.




In particular, when foamy cleaning solvent B is used, this foamy cleaning fluid spreads in the whole area of the ducts


10


B,


10


A by its nature, and is supplied to the heat exchanger


6


side by the compressed air A, and a high cleaning efficiency is maintained, but the cleaning solvent B is not limited to the foamy type alone.




Incidentally, as shown in

FIG. 1

, in the duct


10


B corresponding to one air conditioning area, after supplying the cleaning solvent B together with compressed air A from the blow-out port


16


at the position remotest from the heat exchanger


6


, similarly, the cleaning solvent B may be supplied, together with the compressed air A, from the blowout port


13


in the duct


10


A corresponding to other air conditioning area, or




As in an apparatus of a second embodiment shown in

FIG. 3

, the cleaning solvent B may be supplied together with the compressed air A into both blow-out ports


13


,


16


positioned remotely from the heat exchanger


6


in the ducts


10


A,


10


B in the air conditioning areas, so that both enhancement of cleaning efficiency of the ducts


10


A,


10


B and shortening of cleaning time may be achieved.




After cleaning, of course, the inside of the ducts


10


A,


10


B may be dried by supplying only compressed air A from the blowing fan


17


.




Thus, according to the air intake passage cleaning apparatus of the embodiments, by supplying the cleaning solvent B together with the compressed air A to the heat exchanger


6


side from the blowing fan


17


and solvent source


18


through the ducts


10


A,


10


B, the ducts


10


A,


10


B and the heat exchanger


6


can be cleaned securely by the cleaning solvent B supplied by the air A.




Accordingly, by starting air conditioning operation after cleaning, offensive smell or the like is not generated and the indoor environments may be enhanced.




Moreover, since the cleaning solvent B can be supplied together with the compressed air A through an arbitrary blow-out port out of the blow-out ports


11


to


16


from the blowing fan


17


and solvent source


18


, the ease of cleaning operation can be enhanced. In particular, it is effective when it is hard to supply from the blow-out ports


13


,


16


due to obstacles or the like positioned beneath the blow-out ports


13


,


16


.




Further, since the cleaning solvent B can be supplied together with the compressed air A through the blow-out port


16


at the remotest position from the heat exchanger


6


, out of the blow-out ports


11


to


16


, from the blowing fan


17


and solvent source


18


, if the air intake passage of the ducts


10


B,


10


A is long, the entire length and the heat exchanger


6


can be cleaned securely.




On the other hand, according to an air intake passage cleaning apparatus of an embodiment, when the cleaning solvent B is supplied together with the compressed air A to the heat exchanger


6


side from the blow-out port through the air intake passages (see ducts


10


A,


10


B), the air intake passages and heat exchanger


6


can be securely cleaned by the cleaning solvent B supplied by the air A.




Besides, when supplying the air A and the cleaning solvent B from a specific blow-out port (for example, blow-out port


16


), since the blow-out ports


11


to


15


are closed by the blocking members


24


, the fluid after cleaning is prevented from flowing out from the blow-out ports


11


to


15


, and also the air A is prevented from escaping from the blow-out ports


11


to


15


, so that the air A and cleaning solvent B can be efficiently guided to the heat exchanger


6


side, thereby enhancing the cleaning efficiency.




The air intake passage cleaning method and apparatus in a third embodiment shown in

FIG. 4

comprise cleaning and wiping elements C impregnated with cleaning solvent B and loaded inside of ducts


10


A,


10


B, and a fan


5


for supplying air A in the direction of moving the cleaning and wiping elements C toward a specific blow-out port (for example, blow-out port


16


).




The cleaning and wiping elements C are composed of flexible and elastic members such as sponge, and are formed in a size and shape to abut against the inner wall of the ducts


10


A,


10


B, tightly contacting with almost entire peripheral surface. The cleaning and wiping elements C may be also replaced by, for example, brushes planting multiple bristles, non-woven cloth made from fibers, or cotton-like mesh made of entangled wire materials.




When cleaning, after stopping the fan


5


, the blow-out ports


11


to


15


, except blow-out port


16


, are closed by blocking members


24


, and a blocking member


26


at an entrance


25


formed in the side chamber


9


is opened, and the cleaning and wiping elements C impregnated with solvent are loaded inside the duct


10


B.




After closing the entrance


25


with the blocking member


26


, the fan


5


is driven, and the transfer pressure of the air A is applied positively to the cleaning and wiping elements C, and the cleaning and wiping elements C are moved at once toward the blow-out port


16


side, and the dirt deposits inside the duct


10


are quickly cleaned and removed in a short time by the synergistic actions of the cleaning solvent B and the cleaning and wiping elements C, and by repeating the operation for some times, the remaining dirt can be completely cleaned and removed.




The cleaning solvent B and cleaning and wiping elements C discharged from the blow-out port


16


are recovered, and the cleaning and wiping elements C are washed in water or detergent, and recycled. It is also possible to clean while supplying the cleaning solvent B into the duct


10


B, or to clean the inside of the duct


10


B by dismounting the heat exchanger


6


.




When cleaning the duct


10


A, the blow-out port


13


is opened, and the blow-out ports


11


,


12


,


14


,


15


,


16


are closed and the inside of the duct


10


A is cleaned. By opening the blow-out ports


13


,


16


of the ducts


10


A,


10


B, closing the blow-out ports


11


,


12


,


14


,


15


, and cleaning the ducts


10


A,


10


B simultaneously, the working time can be shortened and the working efficiency can be enhanced.




By laying or applying a protective member (not shown) such as cover and sheet beneath or around a specific blow-out port, the cleaning work can be done cleanly and hygienically.




In this way, since the cleaning and wiping elements C loaded in the ducts


10


A,


10


B are moved by transfer pressure of air A, the dirt deposits of the ducts


10


A,


10


B can be securely and cleanly removed by the synergistic actions of the cleaning solvent B and cleaning and wiping element C, and sanitary environments can be obtained.




Moreover, since the cleaning and wiping elements C are moved simultaneously toward a specific blow-out port (for example, blow-out port


16


). and the time required for removing the dirt deposits inside the ducts


10


A,


10


B is shortened, and the working time can be shortened notably. At the same time, the job can be done simply and easily, and the working efficiency can be enhanced.




The air intake passage cleaning method and its apparatus of a fourth embodiment shown in

FIG. 5

are designed to clean and remove dirt deposits in the ducts


10


A,


10


B by towing and operating linear traction members


31


linked to the cleaning and wiping elements C.




The traction member


31


is composed by coupling and fixing flexible traction wire


32


And traction cord


33


, the cleaning and wiping element C is fixed to the end of the traction wire


32


, and the traction wire


32


and traction cord


33


are formed longer than the distance linking the blow-out port


16


and entrance


25


. Instead of the traction wire


32


, for example, rope, chain or the like may be also used.




When cleaning, the fan


5


is stopped, the blow-out ports


11


to


15


, except blow-out port


16


, are closed, the traction cord


33


is inserted into the inside of the duct


10


B from the entrance


25


side of the side chamber


9


, and the traction wire


32


drawn out to the entrance


25


side and the traction cord


33


drawn out to the blow-out port


15


side are alternately towed and operated by hand, so that the dirt deposits inside the duct


10


B can be cleaned and removed by the synergistic actions of the cleaning solvent B and cleaning and wiping elements C.




Besides, depending on the position and area of dirt, the wiping position by the cleaning and wiping elements C can be freely changed. It is also possible to clean while supplying cleaning solvent B into the duct


10


B.




Alternatively, the traction cord


33


may be also connected through, for example, a connector to the cleaning and wiping element C or traction wire


32


projecting to the blow-out port


16


side. Or, the traction wire


32


and traction cord


33


may be mechanically towed by traction means such as winch.




After drawing out the traction cord


33


to the blow-out port


13


side of the duct


10


, or drawing out to the blow-out port


11


,


12


side of the duct


10


A or the blow-out port


14


,


15


side of the duct


10


B, by towing and manipulating the traction wire


32


and traction cord


33


. the dirt deposits in the ducts


10


A,


10


B can be cleaned and removed by the cleaning and wiping elements C.




Meanwhile, without linking the traction cord


33


, only the traction wire


32


may be inserted into the duct


10


B, and the dirt deposits inside the duct


10


B may be cleaned and removed by the cleaning and wiping elements C fixed to the traction wire


32


.




Incidentally, as shown in

FIG. 6

, for example, by inserting a traction member


31


into a duct


10


C piped in the kitchen or the like, and towing and manipulating the traction wire


32


drawn out to the air intake


32


side and the traction cord


33


drawn out to the exhaust port


35


side, the dirt deposits inside the duct


10


C can be cleaned and removed by the cleaning and wiping elements C.




Also, by loading the cleaning and wiping elements C only in side the duct


10


C, and moving the cleaning and wiping elements C by making use of the transfer pressure by the air A or the negative pressure by the vacuum pump, the dirt deposits inside the duct


10


C can be cleaned and removed.




The air intake passage cleaning method and its apparatus of a fifth embodiment shown in FIG.


7


and

FIG. 8

are designed to clean and remove the dirt while blowing the cleaning solvent B to the inner wall of the ducts


10


A,


10


B.




The cleaning and wiping elements C are fixed to the end of traction pipes


35


formed elastically, holes


37


. . . for discharging the cleaning solvent B around the traction pipes


35


are formed at specific intervals in the length direction, the traction cord


33


and traction pipe


36


are coupled, and the solvent source


18


and traction pipe


36


are connected by a feed line


29


through a pump


27


and a valve


28


.




When cleaning, after inserting the traction pipe


36


and cleaning and wiping elements C into the duct


10


B, the cleaning solvent B stored in the solvent source


18


is supplied into the traction pipe


36


by the pump


27


, and the cleaning solvent B discharged from the holes


37


. . . of the traction pipe


36


is sprayed to the inner wall of the duct


10


B, and the dirt deposits in the duct


10


B are cleaned and removed by the cleaning and wiping elements C, so that the solvent is stably obtained in an amount suited to cleaning, and therefore the cleaning job can be done efficiently




Or, traction pipe


36


may be inserted into the duct


10


B, and the inside of the duct


10


B may be cleaned by the wiping and cleaning elements C fixed in the traction pipe


36


.




Also, as shown in FIG.


9


and FIG.


10


. the traction pipe


36


may be also fitted along the side periphery of the traction wire


32


, and by spraying the cleaning solvent B discharged from the holes


37


. . . of the traction pipe


36


to tile inner wall of the duct


10


B, and the dirt deposits in the duct


10


B are cleaned and removed by the cleaning and wiping elements C.




The air intake passage cleaning method and its apparatus of a sixth embodiment shown in FIG.


11


and

FIG. 12

are designed to clean and remove the dirt deposits from the inside of the ducts


10


A,


10


B, by sector or trapezoidal cleaning and wiping elements C coupled to the traction wire by towing and operating the traction wire


32


along a wire guide


38


.




The traction wire


32


is inserted into the wire guide


38


formed elastically, and the traction wire


32


and cleaning and wiping elements C are integrally coupled through a guide groove


39


formed at the side of the wire guide


38


.




After inserting the wire guide


38


into the duct


10


B, by towing and manipulating the traction wire


32


, the cleaning and wiping elements C impregnated with the solvent are moved along the wire guide


38


, so that the dirt deposits in the duct


10


can be wiped, cleaned and removed accurately, thereby securely preventing dislocation of the wiping position.




At the same time, contact between the duct


10


B and traction wire


32


can be prevented, and the duct


10


B is prevented securely from being broken or damaged. It is also possible to clean while supplying the cleaning solvent B into the duct


10


B.




As shown in FIG.


13


and

FIG. 14

, by coupling the traction wire


32


inserted into the wire guide


38


and the tubular cleaning and wiping element C freely fitted to the outer circumference of the wire guide


38


, towing and manipulating the traction wire


32


, and moving the cleaning and wiping elements C impregnated with solvent along the wire guide


38


, the dirt deposits in the duct


10


B can be cleaned and removed simultaneously, and the working efficiency can be improved.




In the correspondence between the constitution of the invention and the above embodiments,




the air intake passages of the invention correspond to the ducts


10


A,


10


B,


10


C of the embodiments, and similarly,




the supplying means, to the blowing fan


17


and solvent source


18


,




the moving means, to the fan


5


and traction member


31


,




the air supplying means, to the fan


5


, and




the traction member, to the traction member


31


, traction wire


32


, traction cord


33


, and traction pipe


36


,




but the invention is not limited to the illustrated embodiments alone.




For example, in

FIG. 1

,

FIG. 3

,

FIG. 4

, and

FIG. 5

, the object of cleaning is the air conditioner of the central air conditioning system, but it may be also applied to the air conditioners of other types.




Alternatively, mesh members may be disposed inside of the seal member


19


, and the soap water supplied from the solvent line


23


may be foamy, or depending on the structure, since the ducts


10


B,


10


A may be disposed at a higher position than the heat exchanger


6


, so that the lift may be effectively utilized.



Claims
  • 1. A cleaning apparatus for use in cleaning inside walls of a passage through which air travels to or from a heat exchanger and having a plurality of ports, an entrance, and an exit, said apparatus comprising:means for closing said plurality of ports in a leak proof manner; at least one wiping means inserted into said passage through said entrance and removed from said exit, and being of a dimension to abut at least parts of said inside walls of said passage; means for supplying cleaning solvent to said at least one wiping means and to said at least parts of said inside walls so that deposits on said inside walls are contacted by said cleaning solvent; and flexible moving means for holding said at least one wiping means and for moving said at least one wiping means through said passage to cause said deposits to be loosened and removed from said inside walls.
  • 2. The apparatus of claim 1, wherein said means for moving comprises a flexible cord and a hollow pipe attached to said cord, said hollow pipe having a plurality of holes in side walls thereof, and wherein said means for supplying comprises means for supplying said cleaning solvent to said hollow pipe.
  • 3. The apparatus of claim 2, wherein said plurality of holes are disposed in one line extending along a longitudinal direction of said hollow pipe.
  • 4. The apparatus of claim 2, wherein said plurality of holes are disposed in two or more lines extending along a longitudinal direction of said hollow pipe.
  • 5. The apparatus of claim 1, wherein said means for moving comprises a flexible cord extending from one end of said passage to another, and a hollow pipe attached to said cord along an entire length thereof, and wherein said means for supplying comprises means for supplying said cleaning solvent to said hollow pipe.
  • 6. The apparatus of claim 1, wherein said means for moving comprises a guide means disposed within said passage, and holder means disposed along a length of said guide means for holding said at least one wiping means.
  • 7. The apparatus of claim 1, wherein said means for moving comprises guide means disposed along a length of said passage, and holder means surrounding said guide means for holding said at least one wiping means.
  • 8. The apparatus of claim 1, wherein said at least one wiping means comprises a material selected from the group consisting of sponge, brush, non-woven cloth, and wire mesh.
RELATED APPLICATION

This is a division of Ser. No. 09/008,407 filed Jan. 17, 1998, now U.S. Pat. No. 6,047,714 issued Apr. 11, 2000.

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Number Date Country
1024683 Mar 1966 GB
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