|Publication number||US2664050 A|
|Publication date||Dec 29, 1953|
|Filing date||Mar 2, 1949|
|Priority date||Mar 2, 1949|
|Publication number||US 2664050 A, US 2664050A, US-A-2664050, US2664050 A, US2664050A|
|Inventors||Carel F Abresch|
|Original Assignee||Gen Motors Corp|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (22), Referenced by (39), Classifications (8)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Dec. 29, 1953 c. F. ABREscH 2,664,050
DOMESTIC APPLIANCE Filed March 2, 1949 4 Sheets-Sheet l Dec. 29, 1953 c. F. ABRI-:SCH 2,664,050
DOMESTIC APPLIANCE Filed March 2, 1949' 4 Sheets-Sheet 2 FIGA Dec. 29, 1953 c. F. ABRESCH 2,664,050
DOMESTIC APPLIANCE Filed March 2. 1949 4 Sheets-Sheet 3 FIG.9
Dec. 29, 1953 c. F. ABREscH 2,664,050
DOMESTIC APPLIANCE Filed March 2, 1949 4 Sheets-Sheet 4 (M VENTO atenteci Dec. 29, 1.953
UNITED STATES PAT ENT OFFICE DOMESTIC APPLIANCE Carelli?.` Abresch, Dayton, Oliio, assi/gnor to General Motors Corporation, Dayton, Oho,a' corporation of'lela'ware Application. March 2, 1949,- `Ser-iai No.` 79,226
Claims.` (Cl. TO3- 117) This invention `relatesto domestic appliances, and more particularly to domestic washing machines or the like.
Aniobject of this` invention is to provide mechanism. capable of imparting a vacuumA and a super-atmospheric pressure. alternatively in the casing ot the Washing .machine or the like,.which mechanism is` automatically lubricatedby liquid trapped in' the` mechanism.
Another object of. this. invention is to provide a pump-structure for imparting avacuum or superatmospheric pressure alternatively in a washing machine or the like,A which pump structure is adapted toarrest a portion of liquid, for use in lubricating the pumping mechanism Within such a structure.
Further objects. and advantages of the present invention will be apparent fromthe following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.
lin the drawings:
Fig. lis a diagrammatic representationv ofV the pump structure and. ar washing machine;
Fig. 2 is a partial view of the mechanism shown in Fig. l, with the rotor of thepuinp.reversed;
Fig. 3 is an enlarged view of the pump structure shown in Fig. 1;
Fig. 4 is a cross-sectional View takenalong the line 4--4 of Fig. 3;
Fig. 5 is a top View of the mechanism shown in Fig. 3. With the cover removed;
Figs. 6v and '7 show modiled forms of pump cylinder structures;
Fig. 8 showsV the optional use of a check` valve inthe pump structure;
Fig. 9 is an enlarged cross-sectional view of a rotary seal suitable for use with the Washing-machine;v
Fig. 10 is a cross-section along the line III-ill of- Fig. 9; and
Fig. l1 is an elevation, and Fig. 12 acrosssection, along the line I2-I2 of a modified form.
According to this invention. a casing, or Washing machine. l0 is adapted to have vacuum and super-atmospheric pressure alternatively. imparted thereto. By way of example, the Washing machine may. be of. theV character disclosed in my copending application` S. N. 34,038, led', June 19, 1948, for Washing Machines. The washing machine I0 may be provided with a flexibler diaphragm II' secured to the casing I0. A pipe I2. is provided to supply water to the casing. A hinged cover I3 may be provided fory inserting and removing4 clothes. The casing; i0 is adapted to be rotated around the axis I4, I4' to impart. a tumbling action to the liquid and clothes inthe cas- `the chamber 25.
and" is adaptedV to rotate therewithv The pipes I-2 and I5 are provided with rotating` seals. I6"'t'o allowrelative rotation. The. drain I5y is. connected to.V the pipeV Il leading. to the pump struc.- ture I8.: The drainY I5 rotatespast thel'ow point in casing I9 at eachrevolution, and thus is adapted to empty the casing by repeated` travel'. past thislowV point. A pipe ISI is providedforsupplying hot and cold. water from the ValveI structure 2D into the casing. I0 through. pipe, I 2'.. An. outi- Wardly directed, spring-pressed, check valve ZTI is provided to allow excess. air to escape when super-atmospheric pressure is producedA in the casing I0. The portion Ili` of' the casing, isperiforated suiiiciently to allow atmospheric air to enter and exert its pressure on the. diaphragm II, to collapse itagainst the clothes-When a vacuum .is produced in the casing..
The pumpy structure I8 .may include first and second upper chambers 22 and 23 which are separated by a vertical wall; 24.. These chambers are connected at their lower ends, andi at separate points 26 and 2'I,v with a horizontally disposed, generally cylindrical, lower chamber 25.' The connections between this chamber 25 and the chambers 22 and.23 are throughopenings 2B and 2.1 respectively which are formed) on eitherside ofthe abutment. wall 28 at the upper portion of A pipe or conduit 29'is connected .to the upper portion ofthe chamber 23 at oney end, and is adapted toA have its' other end 30 hung over the rim of astationary tub or the like 3 I- at a level higher than. the normalworking fluid level 32Y within the washing machine.
A reversible pump piston or rotor 33 is mounted on the horizontal shaft 34 andv preferably is pro'- vided with iiexible fingers or blades 35i This rotor may have its outer body and fingersv made of iiexible material, such as of rubber, eithernatural or synthetic, or of, any other rubber-like compounds noW well known. Between the flngers, smaller knobs or beads 36. are provided', which tend to reduce the area.. between tiwo lsuccessive fingers, when the lingers pass the abutment 28. rI'his producesa pumping action, due to ther decreased area between" the'ngers at this: point;
Preferably the cross-sectional' areas of the pipes. I1 and 29 are smaller' than the cross-sectional areas respectively of the chambers 2v2 and 23. The construction is Ysuch that, when a mii(- ture of gas and liquid is being pumped by the rotor 33, a certain amount of' liquid isltrapped inf-one or theother o1"l chambers 212l or 23,-while the excess liquid is forced out the pipe 29'.: A`=s 'shown in- Fig. 3; the rotor v33'isrotating'clockwise, and: pumping gas (air)i 'through the* body la cylindrical extension 1|.
of liquid whose level is indicated at 40, the air being indicated by bubbles 4|, which in actual use produce more turbulence than is diagrammatically indicated at 4|. The gas continues through the pipe 29. A small amount of liquid passes with the fingers 35 past the abutment 28, and helps to maintain the pump structure cooled and lubricated. Should the rotor 33 of Fig. 3 be reversed, the liquid in chamber 23 will be transferred to chamber 22, and will reach a level 42 somewhat lower than level 48, since the chamber 22 is larger than chamber 23. This will permit the pump to pump air through the pipe I1 into the casing I without sending any liquid into the chamber I0 to wet the clothes therein. The condition shown in Fig. 2 occurs when water is maintained in casing IG to wash the clothes, while the condition shown in Fig. 3 occurs when the clothes are dried.
In the embodiment shown in Figs. 3 and 4, the chamber 25 is substantially circular in crosssection, with the rotor shaft 34 at the center of the circle. The chamber 25 is provided with an oiiset abutment 28, which produces the pumping action. In the modication shown in Fig. 6, the chamber 25a is somewhat elliptical, and the rotor 33a rotates about an axis nearer the upper portion of the chamber 25a. In Fig. 7 the lower half of chamber 25h is semi-circular, with its radius about the point 58. The upper portion of the chamber 25h may be circular, with a much larger radius, with its center below the point 58. The shaft 34h has its center above the point 50 and produces a compressing action, as the fingers 35h pass around the upper portion of the chamber 2522.
In the modification shown in Fig. 8, a check valve 5| is placed between the chambers 22e and 23c. This check valve is spring-pressed a suflicient amount to impart the desired superatmospheric pressure within the casing I9. If a check valve 5| is used, as shown in Fig. 8, then the check valve 2|, shown in Fig. 1, may be omitted, if desired.
The rotary seals indicated at I6 in Fig. 1 may be of the construction shown in Figs. 9 and 10.
The pipes I5 and I1 of Fig. 1 for example, may be threaded on threads 80 and 6I respectively. The thread 68 is formed on a cylindrical xture 62. 'Ihis xture has a smooth internal bore 63, and terminating in a flange B4. The fixture 82 has a smooth plane surface 65 adjacent the ange 64. A bearing ring 66, of self lubricating bearing metal composition, is placed over the xture 62 and extends over the flange 64 at 61.
Another xture 68 carries the thread BI and is also provided with a smooth internal bore 69. This fixture terminates in a flange 18 which has The extension 1| is externally threaded at 12. The flange 10 is provided with a smooth plane surface 13, in which an annular notch 14 is formed.
A rubber-like ring 15, of neoprene or the like, is placed in the notch 14, and thereafter the clamping ring 18 is threaded on threads 12. The ring 16 is provided with inward flange 11 which locks the bearing ring 66 in place. The ring 68, in turn, locks the fixture 82 in place by its action on ange 64. The action of ring 16 also compresses the rubber-like ring slightly to make a water-tight construction at this point. A locking screw 18 holds the ring 16 in proper adjustment.
It is to be noted that the bearing ring 66 assumes all the bearing strains of the seal, while 4 the rubber-like ring 15 assumes all of the sealing functions. This produces a simple and efiicient rotating seal, particularly adapted for use in a washing machine of the character herein disclosed.
In the operation of the machine, the cover I3 is opened preferably while it is at its upper p0- sition of travel, and clothes and detergent are inserted in casing III. The cover I3 is then closed. Water of the desired temperature is admitted through the pipe line I9 by the operation of the valve structure 20, which mixes hot and cold waters from the usual supply pipes. liquid is inserted approximately to the level 32. The casing I8 is then rotated in one direction, by belts (not shown) which are also connected to the pump rotor 33. At this time the rotor 33 rotates counterclockwise, as shown in Fig. 2, and pumps a certain amount of air into the casing I0 and maintains it at a slightly super-atmospheric pressure. The excess air flows out past check valve 2|. This maintains the diaphragm II in the position shown in Fig. 1, distended against the wall Ica.. The water and clothes are tumbled by suitable bafiles 35 in the casing |8. After a suitable time, the rotation of the casing I0 and rotor 33 are reversed, causing the water to be pumped out of the casing III and to be discharged into the stationary tub 3|, as shown in Fig. 1. The pumping of liquid continues until the casing I0 is emptied, it being noted that the pipe I6 rotates repeatedly past the lowest portion of the casing I0 to completely empty the water. Thereafter continued rotation pumps out the air remaining in the casing I0, the air bubbling through the liquid trapped in the chamber 23, as shown in Fig. 3, and is discharged through the pipe 29. This action imparts a vacuum within the chamber I8, and causes the diaphragm to be pressed against the clothes to squeeze them dry. After the drying or squeezing action has proceeded a sufficient length of time, rotation is again reversed, to pump a certain amount of air into the casing I8, to break the vacuum therein, and to force the diaphragm II to its distended position. At the time of this reversal, the liquid in casing I0 is transferred from chamber 23 to the dotted position 42 in chamber 22, which permits pumping air without water into casing I0.
Thereafter one or more rinsing actions can be performed by introducing water without detergent and agitating and squeezing the clothes in the same manner as for washing.
Figs. 11 and 12 show a modification of a pump, which may be connected to the system shown in Fig. l at I1 and 25. The inlet 89 may be connected to the pipe I1, and the outlet 8| may be connected to the discharge pipe 29. The casing 82 is provided with a cover 83 which is bolted thereto. A shaft 84 carries a hub 85 on which is mounted a rubber-like rotor 86 having radial fingers 81. The rotor 88 is placed inside of a partly cylindrical inner casing 88, which has an eccentric portion 89. A copper lining 90 is provided inside of the casing 88. An outlet opening 9| is placed between the inner portion of the casing 88 and the inner portion of the casing 82. The casing 88 is substantially surrounded with liquid which is trapped in the casing 82, when liquid with or without air is being pumped from the inlet 88 to the outlet 8|. A baffle 92 is built in the casing 82 for the purpose of trapping liquid, when the mixture of liquid and air are being pumped.
In the operation of this modification, when liquid alone, or liquid in air, are being pumped from 89 to 8i, by rotation of the rotor in a clockwise direction, liquid is trapped in casing 82, and surrounds the inner casing 88. Any heat which is generated in the rotor 86, is dissipated to the liquid in the casing 62, thus preventing any high temperature within the rotor.
While the form ci embodiment of the invention as herein disclosed, constitutes a preferred :"orin, it is to be understood that other forms might be adopted, as may come within the scope ci the claims which follow.
What is claimed is as follows:
1. A pump including a rotary impeller, said impeller being provided with a plurality of substantially uniformly spaced blades, a casing surrounding the impeller ntting against the ends of the blades and extendinginto contact with the tips of the blades and forming an impeller chamber, said casing having an inlet and an outlet communicating with the impeller chamber, said impeller being provided with axially parallel rounded radially projecting beads between every two adjacent blades extending a lesser distance from the axis of rotation than the blades, a portion of the casing between the inlet andthe outlet being suiiiciently near the axis of the impeller to fold the blades into substantially continuous engagement with the adjacent portion of said beads from the inlet to the outlet so that the beads act like a bending fixture to force uniform bending er the blades as the impeller rotates, said blades being formed principally of a flexible rubberdixe material.
2. A. pump including a rotary impeller, said impeller being provided with a plurality of substantially uniformly spaced blades, a casing surrounding the impeller iitting against the ends of the blades and extending into contact with the 'tips of the blades and forming an impeller charnber, said casing having an inlet and an outlet communicating with the impeller chamber, said impeller being provided with axially parallel rounded radially projecting beads between every two adjacent blades extending a lesser distance from the axis of rotation than the blades, a portion of the casing between the inlet and the outlet being suinciently near the axis of the impeller to fold the blades into substantially continuous engagement with the adjacent portion of said beads from the inlet to the outlet so that the beads act like a bending fixture to force uniform bending ci the blades as the impeller rotates,
said blades and said beads being formed principally of a iiexible rubber-like material.
3. A pump including a rotary impeller, said impeller being provided with a plurality of substantially uniformly spaced radially extending blades, a casing surrounding the impeller tting against the ends of the blades and extending into contact with the tips of the blades and forming an impeller chamber, said casing having an inlet and an outlet communicating with the impeller chamber, said impeller being provided with axially parallel half round radially projecting beads extending substantially the entire distance between every two adjacent blades in the axial direction and extending a lesser distance from the axis of rotation than the blades, a portion of the casing between the inlet and the loutlet being suiciently near the axis of the impeller to fold the blades into substantially continuous engagement with the adjacent portion of said beads from the inlet to the outlet so that the beads act like a bending xture to force uniform bending of the blades as the impeller rotates, said blades being formed principally of a iiexible rubber-like material.
4. A pump including a rotary impeller, said impeller being provided with a plurality of substantially uniformly spaced radially extending blades, a casing surrounding the impeller iitting against the ends of the blades and extending into contact with the tips of the blades and forming an impeller chamber, said casing having an inlet and an outlet communicating with the impeller chamber, said impeller being provided with axially parallel half round radially projecting beads extending substantially the entire distance between every two adjacent blades in the axial direction and extending a lesser distance from the axis of rotation than the blades, a porn tion of the casing between the inlet and the outlet being sufficiently near the axis of the impeller to fold the blades into substantially continuous engagement with the adjacent portion of said beads from the inlet to the outlet so that the beads act like a bending xture to force uniform bending of the blades as the impeller rotates, said blades and said beads being formed principally oi a flexible rubber-like material.
5. A reversible pump for both liquids and gases including a casing, a reversible rotary impel- 1er having means in sealing Contact with the inner walls of the casing, said casing having at least two openings above the impeller interchangeable for intake and discharge upon reversal of the impeller, a iirst reservoir extending above and communicating with one of said openings, a second reservoir extending above and communicating with the second of said openings, said rst reservoir having a capacity exceeding the net fluid space within the casing, said second reservoir having a capacity substantially exceeding the capacity of the rst reservoir, said reservoirs each having an opening adjacent their top interchangeable for intake and discharge upon reversal of the impeller.
CAREL F. ABRESCH.
References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 43,849 Hinds Aug. 16, 1864 '1,188,737 Cutler June 27, 1916 1,233,069 Leonard July 10, 1917 1,535,310 Hobson Apr. 28, 1925 1,683,143 Peterson Sept. 4, 1928 1,823,098 Hargis Sept. 15, 1931 2,013,260 Waterous et al. Sept. 3, 1935 2,189,356 Briggs Feb. 6, 1940 2,203,974 Weinhardt June 11, 1940 2,293,268 Quiroz Aug. 18, 1942 2,312,341 King Mar. 2, 1943 2,835,560 Crane Nov. 80, 1943 2,364,469 Orr Dec. 5, 1944 2,426,491 Dillon Aug. 26, 1947 2,433,484 Roth Dec. 30, '1947 2,438,529 Woodling Mar. 30, 1948 2,455,043 Calhoun Nov. 30, 1948 2,456,651 Schmiel Dec. 21, 1948 2,472,682 Rand June 7, 1949 2,498,420 Hemmeter Feb. 21, 1950 2,499,163 Rand Feb. 28, 1950 FOREIGN PATENTS Number Country Date 348,748 Great Britain May 21, 1931
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US43849 *||Aug 16, 1864||Improvement in rotary pumps|
|US1188737 *||Jul 10, 1913||Jun 27, 1916||Leonard Rotary Pump Corp||Rotary pressure or vacuum pump.|
|US1233069 *||May 22, 1916||Jul 10, 1917||Leonard Pump And Motor Co||Pump and liquids.|
|US1535310 *||Aug 8, 1921||Apr 28, 1925||Roper Corp Geo D||Gear pump|
|US1683143 *||May 7, 1927||Sep 4, 1928||Peterson Francis C||Rotary pump|
|US1823098 *||Jun 12, 1928||Sep 15, 1931||Frederick Iron & Steel Company||Gear pump|
|US2013260 *||Aug 10, 1933||Sep 3, 1935||Waterous Co||Pump and pump assembly|
|US2189356 *||Aug 2, 1938||Feb 6, 1940||Briggs Arthur M||Rotary pump|
|US2203974 *||Feb 8, 1937||Jun 11, 1940||Alfred Vang||Pump|
|US2293268 *||Apr 21, 1941||Aug 18, 1942||Angel Quiroz Francisco||Rotary pump|
|US2312341 *||Mar 4, 1939||Mar 2, 1943||King Walter E||Packed swivel joint|
|US2335560 *||Nov 26, 1940||Nov 30, 1943||Brayton Morton||Laundry apparatus|
|US2364469 *||Sep 22, 1942||Dec 5, 1944||Orr Donald J||Reversible hydraulic pump|
|US2426491 *||Apr 1, 1944||Aug 26, 1947||Dillon Irving W||Variable delivery movable vane pump for a fluid transmission mechanism|
|US2433484 *||Nov 24, 1944||Dec 30, 1947||Borg Warner||Movable vane variable displacement pump|
|US2438529 *||Jan 25, 1945||Mar 30, 1948||George V Woodling||Sleeve nut coupling|
|US2455043 *||Apr 5, 1946||Nov 30, 1948||Calhoun Ann E||Clothes cleansing and fluid extracting apparatus having a flexible clothes squeezingdiaphragm|
|US2456651 *||Oct 11, 1946||Dec 21, 1948||Hydraulic Equipment Company||Tank unit with submerged valve and external pump|
|US2472682 *||Jul 9, 1946||Jun 7, 1949||H J Rand Washing Machine Corp||Washing machine with squeezer extractor|
|US2498420 *||Jul 17, 1944||Feb 21, 1950||Hemmeter George T||Combination clothes washer and extractor|
|US2499163 *||Jan 31, 1948||Feb 28, 1950||H J Rand Washing Machine Corp||Rotary pump|
|GB348748A *||Title not available|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US2772637 *||Mar 20, 1952||Dec 4, 1956||Jabsco Pump Co||Impeller pump|
|US2789511 *||May 25, 1953||Apr 23, 1957||Jabsco Pump Co||Flexible vane pump impeller|
|US2856859 *||Jan 7, 1955||Oct 21, 1958||Visioneering Company Inc||Pump|
|US2899902 *||Apr 4, 1957||Aug 18, 1959||Rotary pump impeller|
|US3054355 *||Apr 25, 1961||Sep 18, 1962||Lord Mfg Co||Pump|
|US3080824 *||Feb 27, 1961||Mar 12, 1963||Boyd James A||Fluid moving device|
|US3185385 *||Apr 16, 1962||May 25, 1965||Floyd J Moltchan||Rotary air pump|
|US3211103 *||Feb 7, 1962||Oct 12, 1965||Kiekhaefer Corp||Rotary vane-type pump structure|
|US3582235 *||Nov 5, 1969||Jun 1, 1971||Ito Heijiro||Rotary pump|
|US3804011 *||Mar 5, 1971||Apr 16, 1974||Zimmer P||Roller squeegee with resilient teeth to increase liquid penetration|
|US3807302 *||Jul 20, 1971||Apr 30, 1974||Zimmer P||Roller squeegee device with fluid pressure increasing means|
|US3832105 *||Jul 21, 1972||Aug 27, 1974||Takahashi K||Flexible blade rotary pump|
|US4940402 *||Nov 8, 1988||Jul 10, 1990||Brunswick Corporation||High pressure and high lift pump impeller|
|US5449280 *||Apr 7, 1994||Sep 12, 1995||Hypro Corporation||Pump including integral reservoirs for permitting dry run of pump|
|US5660536 *||Jan 5, 1996||Aug 26, 1997||Brunswick Corporation||High capacity simplified sea water pump|
|US7841976||Mar 23, 2007||Nov 30, 2010||Thoratec Corporation||Heart assist device with expandable impeller pump|
|US7927068||Apr 19, 2011||Thoratec Corporation||Expandable impeller pump|
|US7998054||Sep 23, 2009||Aug 16, 2011||Thoratec Corporation||Implantable heart assist system and method of applying same|
|US8118724||Dec 4, 2007||Feb 21, 2012||Thoratec Corporation||Rotary blood pump|
|US8376707||Feb 19, 2013||Thoratec Corporation||Expandable impeller pump|
|US8485961||Jan 4, 2012||Jul 16, 2013||Thoratec Corporation||Impeller housing for percutaneous heart pump|
|US8535211||Jul 1, 2010||Sep 17, 2013||Thoratec Corporation||Blood pump with expandable cannula|
|US8591393||Jan 5, 2012||Nov 26, 2013||Thoratec Corporation||Catheter pump|
|US8597170||Jan 4, 2012||Dec 3, 2013||Thoratec Corporation||Catheter pump|
|US8684902||Dec 4, 2007||Apr 1, 2014||Thoratec Corporation||Rotary blood pump|
|US8684904||Aug 15, 2013||Apr 1, 2014||Thoratec Corporation||Blood pump with expandable cannula|
|US8721517||Mar 13, 2013||May 13, 2014||Thoratec Corporation||Impeller for catheter pump|
|US8992163||Jan 11, 2013||Mar 31, 2015||Thoratec Corporation||Expandable impeller pump|
|US9091261||Aug 9, 2010||Jul 28, 2015||Pentair Flow Technologies, Llc||Dry run porting system|
|US9138518||Jan 6, 2012||Sep 22, 2015||Thoratec Corporation||Percutaneous heart pump|
|US9308302||Mar 13, 2014||Apr 12, 2016||Thoratec Corporation||Catheter pump assembly including a stator|
|US9327067||May 13, 2013||May 3, 2016||Thoratec Corporation||Impeller for catheter pump|
|US9358329||Mar 13, 2013||Jun 7, 2016||Thoratec Corporation||Catheter pump|
|US9364592||Nov 12, 2010||Jun 14, 2016||The Penn State Research Foundation||Heart assist device with expandable impeller pump|
|US9364593||Sep 14, 2012||Jun 14, 2016||The Penn State Research Foundation||Heart assist device with expandable impeller pump|
|US9381288||Mar 11, 2014||Jul 5, 2016||Thoratec Corporation||Fluid handling system|
|US20110030822 *||Feb 10, 2011||Bear Patrick A||Dry Run Porting System|
|DE1143779B *||May 16, 1956||Feb 21, 1963||Whirlpool Co||Automatische Waschmaschine|
|EP1789314A2 *||Sep 16, 2005||May 30, 2007||The Penn State Research Foundation||Expandable impeller pump|
|U.S. Classification||418/154, 68/21|
|International Classification||D06F23/02, D06F39/08|
|Cooperative Classification||D06F23/02, D06F39/085|
|European Classification||D06F23/02, D06F39/08D2|