FR2520059A1 - HYDRAULIC PUMP WITH CONTROLLED DISCHARGE VALVES - Google Patents

HYDRAULIC PUMP WITH CONTROLLED DISCHARGE VALVES Download PDF

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Publication number
FR2520059A1
FR2520059A1 FR8200573A FR8200573A FR2520059A1 FR 2520059 A1 FR2520059 A1 FR 2520059A1 FR 8200573 A FR8200573 A FR 8200573A FR 8200573 A FR8200573 A FR 8200573A FR 2520059 A1 FR2520059 A1 FR 2520059A1
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FR
France
Prior art keywords
valve
rod
piston
pump
bias plate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
FR8200573A
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French (fr)
Inventor
Louis-Claude Porel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LEDUC RENE HYDRO SA
Original Assignee
LEDUC RENE HYDRO SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by LEDUC RENE HYDRO SA filed Critical LEDUC RENE HYDRO SA
Priority to FR8200573A priority Critical patent/FR2520059A1/en
Priority to DE19823247290 priority patent/DE3247290A1/en
Publication of FR2520059A1 publication Critical patent/FR2520059A1/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/14—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
    • F04B1/141—Details or component parts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/14—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
    • F04B1/18—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders having self-acting distribution members, i.e. actuated by working fluid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B7/00—Piston machines or pumps characterised by having positively-driven valving

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)

Abstract

The invention relates to a hydraulic pump having hollow pistons (3) which are arranged parallel to the drive axis and are set into reciprocating motion by means of a swashplate (7), pump delivery being effected via discharge valves (12) which are arranged downstream of the hollow pistons (3) and are pretensioned (biased) by means of restoring springs (13). Each valve (12) of this pump has a stem (14) assigned to it whose movement is controlled from the swashplate (7) and which both lifts the valve (12) to open it, and guides it, so as to produce a delay, during its closure.

Description

La présente invention concerne un perfectionnement aux pompes hydrauliques à plateau biais dans lesquelles les pistons sont disposés parallèlement à l'axe de la pompe et sont animés d'un mouvement de va et vient par 1 1intermé- diaire d'un plateau biais appelé également plateau oscillant. The present invention relates to an improvement to hydraulic pumps with a bias plate in which the pistons are arranged parallel to the axis of the pump and are moved back and forth by means of a bias plate known as a plate. oscillating.

Dans les pompes de ce type, il est connu de disposer des clapets de refoulement qui sont contretenus par des ressorts de rappel. Ces ressorts sont en général tarés de façon a ne s'ouvrir que pour une pression de l'ordre de 1,5 bar et au-dessus. De ce fait ces pompes présentent deux inconvenients :
Le premier inconvenient provient de ce que ces pompes ne peuvent pas s'amorcer seules eut doivent avoir une alimentation sous pression, ce qui s'obtient soit en mettant le réservoir sous une pression d'air ou de gaz soit en disposant le reservoir au-dessus de la pompe.In pumps of this type, it is known to have discharge valves which are constrained by return springs. These springs are generally calibrated so as to open only for a pressure of the order of 1.5 bar and above. As a result, these pumps have two drawbacks:
The first drawback stems from the fact that these pumps cannot be started alone or must have a pressurized supply, which is obtained either by putting the tank under air or gas pressure or by placing the tank at above the pump.

L'incapacité de ces pompes a s' auto-amorcer provient de ce que le rapport volumétrique entre les deux positions extrêmes des pistons n'est pas suffisant pour comprimer suffisamment l'air, quand la pompe est vide, pour avoir une pression assez forte pour soulever les clapets.The inability of these self-priming pumps stems from the fact that the volumetric ratio between the two extreme positions of the pistons is not sufficient to sufficiently compress the air, when the pump is empty, to have a pressure strong enough to lift the valves.

Le deuxième inconvénient provient de ce que la fermeture des clapets est toujours très brutale ce qui confère a ces pompes un niveau sonore tres important, parfois supérieur au niveau sonore maximum accepté dans les ateliers par les reglements.  The second drawback stems from the fact that the closing of the valves is always very abrupt, which gives these pumps a very high noise level, sometimes higher than the maximum noise level accepted in workshops by the regulations.

La présente invention a pour objet un dispositif de commande des clapets de refoulement qui permet d'eliminer ces deux inconvénients. The present invention relates to a device for controlling the discharge valves which makes it possible to eliminate these two drawbacks.

La pompe selon la présente invention est caractérisée par le fait que chaque clapet de refoulement est associé avec une tige de levée, elle-même actionnée par le plateau biais qui commande mécaniquement la levée du clapet et qui ralentit son mouvement de fermeture
Cette tige peut soit prendre directement appui sur la surface active du plateau biais, soit être associée a un piston.The pump according to the present invention is characterized in that each delivery valve is associated with a lifting rod, itself actuated by the bias plate which mechanically controls the lifting of the valve and which slows down its closing movement.
This rod can either rest directly on the active surface of the bias plate, or be associated with a piston.

A titre d'exemple non limitatif et pour faciliter la compréhension de l'invention, on a représenté aux dessins annexés
Figure 1 une vue schématique partielle en coupe axiale d'une pompe munie de clapets de refoulement selon la présente invention ;
Figure 2 une vue partielle en plan selon F de la figure 1 ;
Figure 3 une vue schématique partielle d'une première variante de réalisation illustrant un piston et son clapet de refoulement ;
Figures 4 et 5 deux vues schématiques, partielles, représentant deux postions voisines d'un piston et de son clapet de refoulement selon une deuxième variante de réalisation ;
Figures6 et 7 deux vues en plan correspondant respectivement aux figures 4 et 5.By way of nonlimiting example and to facilitate understanding of the invention, there is shown in the accompanying drawings
Figure 1 a partial schematic view in axial section of a pump provided with discharge valves according to the present invention;
Figure 2 a partial plan view along F of Figure 1;
Figure 3 a partial schematic view of a first alternative embodiment illustrating a piston and its discharge valve;
Figures 4 and 5 two schematic views, partial, showing two neighboring positions of a piston and its discharge valve according to a second alternative embodiment;
Figures 6 and 7 two plan views corresponding to Figures 4 and 5 respectively.

Les pompes à pistons axiaux animés par plateau oscillant étant largement connues ne sont pas décrites de façon détaillées et on n'a represente aux dessins annexés que les éléments nécessaires pour la compréhension de l'invention. La pompe comporte donc un corps 1 fixe, percé d'une pluralité d'alésages 2, parallèles à l'axe de la pompe. Since the axial piston pumps driven by a swash plate are widely known, they are not described in detail and only the elements necessary for understanding the invention are shown in the accompanying drawings. The pump therefore comprises a fixed body 1, pierced with a plurality of bores 2, parallel to the axis of the pump.

Dans ces alésages. se déplacent des pistons creux 3, chaque piston étant contretenu par un ressort 4. La tête, partiellement sphérique de chaque piston 3 repose, par l'intermédiaire d'un plot de glissement 5 contre la face 6 d'un plateau biais 7 entrai nué en rotation par un arbre 8. La rotation de l'arbre 8 provoque une oscillation de la surface 6 du plateau 7 et les pistons 3 sont animés d'un mouvement alternatif.Au cours de la phase d'aspiration, lorsqu'un plot 5 passe au-dessus de la lunule 9, gravée sur la face 6 du plateau 7, le liquide hydraulique passe de ladite lunule vers l'intérieur du piston 3 à travers le plot 5 ; au cours de la phase de refoulement, le plot 5 glissant sur une surface unie, le liquide ne peut plus s'echapper a travers le plot et est comprimé ; il s'echappe par la canalisation 10 qui communique avec un conduit de refoulement 11 a travers un clapet de refoulement 12 contretenu par un ressort 13. In these bores. move hollow pistons 3, each piston being constrained by a spring 4. The partially spherical head of each piston 3 rests, by means of a sliding pad 5 against the face 6 of a bias plate 7 entrained in rotation by a shaft 8. The rotation of the shaft 8 causes the surface 6 of the plate 7 to oscillate and the pistons 3 are driven in an alternating movement. During the suction phase, when a stud 5 passes over the lunula 9, engraved on the face 6 of the plate 7, the hydraulic fluid passes from said lunula towards the inside of the piston 3 through the stud 5; during the delivery phase, the stud 5 sliding on a smooth surface, the liquid can no longer escape through the stud and is compressed; it escapes through the pipe 10 which communicates with a discharge conduit 11 through a discharge valve 12 held in place by a spring 13.

Selon la présente invention chaque clapet 12 est solidaire d'une tige 14 qui coulisse librement dans un alesage 15 ménagé dans le corps de pompe 1, On voit que lorsque la surface 6 du plateau biais 7 oscille, elle vient en contact avec l'extrémité arrondie 14a de la tige 14 et qu'ainsi le clapet 12 est souleve mécaniquement par le plateau biais 7 quelle que soit la force du ressort de rappel 13, On obtient ainsi deux résultats : d'une part le clapet 12 est ouvert automatiquement même si le piston 3 correspondant pompe de l'air et n'arrive pas à le comprimer a une pression suffisante pour vaincre la resistance du ressort de rappel 13 : la pompe est donc auto-amorçante d'autre part la course de fermeture du clapet est progressive ce qui diminue considérablement le bruit-provoqué par la fermeture brutale des clapets 12. According to the present invention each valve 12 is integral with a rod 14 which slides freely in a bore 15 formed in the pump body 1. It can be seen that when the surface 6 of the bias plate 7 oscillates, it comes into contact with the end. rounded 14a of the rod 14 and that thus the valve 12 is lifted mechanically by the bias plate 7 whatever the force of the return spring 13, Two results are thus obtained: on the one hand the valve 12 is opened automatically even if the corresponding piston 3 pumps air and cannot compress it to a sufficient pressure to overcome the resistance of the return spring 13: the pump is therefore self-priming on the other hand the valve closing stroke is progressive which considerably reduces the noise caused by the sudden closing of the valves 12.

Cependant, la course d'ouverture et de fermeture des clapets est fonction de l'inclinaison de la face 6 du plateau 7 et peut dans certains cas être trop longue. Pour remédier à cela, on peut,comme cela est représenté aux figures 1 et 2 disposer sur la face 6 du plateau 7 une came bombée 16 qui accelere le mouvement de levée et de descente du clapet. Dans l'exemple représenté, cette came additionnelle 16 est symétrique par rapport à l'axe de plus grande pente due la face 6 du plateau 7 mais on peut disposer une came dissymétrique et avoir ainsi des temps d'ouverture et de fermeture des clapets qui sont différents. However, the opening and closing stroke of the valves is a function of the inclination of the face 6 of the plate 7 and can in some cases be too long. To remedy this, it is possible, as shown in FIGS. 1 and 2, to have on the face 6 of the plate 7 a cambered cam 16 which accelerates the movement of lifting and lowering of the valve. In the example shown, this additional cam 16 is symmetrical with respect to the axis of greatest slope due to the face 6 of the plate 7, but an asymmetrical cam can be arranged and thus have opening and closing times of the valves which are different.

Sur la figure 3, on a représenté u-ne première variante de réalisation, mais pour simplifier la figure, on n'a représenté qu'un seul piston 3 et une portion du plateau biais 7. Selon cette variante de réalisation, la tige 14 passe au milieu du piston 3. Dans ce cas, le clapet 12 est place exactement derrière le piston 3, coaxialement à ce dernier. De préférence, le plot de glissement 5 comporte en son centre un manchon 17 assurant un guidage de la tige 14. Le fonctionnement est le même que dans le cas des figures 1 et 2. In Figure 3, there is shown a u-first embodiment, but to simplify the figure, there is shown only one piston 3 and a portion of the bias plate 7. According to this embodiment, the rod 14 passes in the middle of the piston 3. In this case, the valve 12 is placed exactly behind the piston 3, coaxial with the latter. Preferably, the sliding stud 5 has at its center a sleeve 17 ensuring guidance of the rod 14. The operation is the same as in the case of FIGS. 1 and 2.

Sur les figures 4 a 7, on a representé une deuxième variante de réalisation ; les figures 4 et 5 représentent un seùl et même piston creux 3 dans deux positions légère- ment décalées par rapport a l'axe de plus grande pente du plateau biais 7 comme cela est illustré aux figures 6 et'7 qui correspondent respectivement aux figures 4 et 5. In Figures 4 to 7, there is shown a second embodiment; Figures 4 and 5 show a single and same hollow piston 3 in two positions slightly offset from the axis of greatest slope of the bias plate 7 as illustrated in Figures 6 and '7 which correspond respectively to Figures 4 and 5.

Selon cette variante de réalisation, on a disposé a l'intérieur de chacun des pistons 3 une tige 18 qui est solidaire dudit piston . Ainsi, c'est le piston 3, refoule par la face 6 du plateau 7, qui, en fin de course > soulève le clapet 12 par l'intermédiaire de la tige 18.  According to this variant embodiment, a rod 18 is arranged inside each of the pistons 3 which is integral with said piston. Thus, it is the piston 3, driven back by the face 6 of the plate 7, which, at the end of the stroke> lifts the valve 12 via the rod 18.

Claims (5)

REVENDICATIONS 1. Pompe hydraulique du type a pistons creux (3) parallèles a l'axe, animes d'un mouvement de va et vient par un plateau biais (7), le refoulement de la pompe s'effectuant par des clapets de refoulement (12) placés en aval desdits pistons, lesdits clapets (12) etant contretenus par des ressorts (13), caractérisée par le fait que chaque clapet de refoulement est soulevé pour son ouverture par une tige (14, 18) dont le mouvement est commandé par le plateau biais (7) et guide pour sa fermeture par la même tige (14, 18). 1. Hydraulic pump of the hollow piston type (3) parallel to the axis, driven back and forth by a bias plate (7), the pump discharge being effected by discharge valves (12 ) placed downstream of said pistons, said valves (12) being constrained by springs (13), characterized in that each discharge valve is raised for its opening by a rod (14, 18) whose movement is controlled by the bias plate (7) and guide for its closure by the same rod (14, 18). 2. Pompe selon la revendication 1, dans laquelle chaque clapet de refoulement (12) est solidaire d'une tige (14) coulissant dans un alésage (15) ménagé dans le corps (1) de la pompe, ladite tige 14 prenant contact avec la surface inclinée (6) du plateau biais (7) par son extrémité (14a) et étant ainsi dans un premier temps repoussée par le plateau biais (7) ce qui soulève le clapet (12) et dans un deuxième temps ralentie dans son mouvement de descente pour la fermeture dudit clapet (12). 2. Pump according to claim 1, wherein each discharge valve (12) is integral with a rod (14) sliding in a bore (15) formed in the body (1) of the pump, said rod 14 making contact with the inclined surface (6) of the bias plate (7) by its end (14a) and thus being initially pushed back by the bias plate (7) which raises the valve (12) and secondly slowed down in its movement descent for closing said valve (12). 3. Pompe selon la revendication 1, dans laquelle chaque clapet de refoulement (12) est solidaire d'une tige (14) traversant le piston (3) ainsi que le plot glissant (5) interposé entre la tête du piston (3) et la face inclinée (6) du plateau (7) ; de sorte que ladite tige (14) est, dans un premier temps, repoussee par le plateau biais (7), ce qui souleve le clapet (12) et, dans un deuxième temps, ralentie dans son mouvement de descente lors de la fermeture dudit clapet (12). 3. Pump according to claim 1, wherein each discharge valve (12) is integral with a rod (14) passing through the piston (3) as well as the sliding stud (5) interposed between the head of the piston (3) and the inclined face (6) of the plate (7); so that said rod (14) is, at first, pushed back by the bias plate (7), which raises the valve (12) and, secondly, slows down in its downward movement when closing said valve (12). 4. Pompe selon la revendication 3, dans laquelle des moyens de guidage (17) pour la tige (14) sont disposés a l'intérieur du piston (3). 4. Pump according to claim 3, wherein guide means (17) for the rod (14) are arranged inside the piston (3). 5. Pompe selon la revendication 1, dans laquelle chaque piston (3) est solidaire d'une tige (18) au moyen de laquelle dans un premier temps, il soulève le clapet (12) lorsqu'il est lui-meme repoussé par la face inclinée (6) du plateau biais (7) et dans un deuxième temps, il ralentit le mouvement de fermeture du clapet (12).  5. Pump according to claim 1, wherein each piston (3) is integral with a rod (18) by means of which at first, it raises the valve (12) when it is itself pushed back by the inclined face (6) of the bias plate (7) and in a second step, it slows down the closing movement of the valve (12).
FR8200573A 1982-01-15 1982-01-15 HYDRAULIC PUMP WITH CONTROLLED DISCHARGE VALVES Withdrawn FR2520059A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FR8200573A FR2520059A1 (en) 1982-01-15 1982-01-15 HYDRAULIC PUMP WITH CONTROLLED DISCHARGE VALVES
DE19823247290 DE3247290A1 (en) 1982-01-15 1982-12-21 Hydraulic pump

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR8200573A FR2520059A1 (en) 1982-01-15 1982-01-15 HYDRAULIC PUMP WITH CONTROLLED DISCHARGE VALVES

Publications (1)

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FR2520059A1 true FR2520059A1 (en) 1983-07-22

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FR8200573A Withdrawn FR2520059A1 (en) 1982-01-15 1982-01-15 HYDRAULIC PUMP WITH CONTROLLED DISCHARGE VALVES

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FR (1) FR2520059A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL9400911A (en) * 1994-06-06 1996-01-02 Applied Power Inc Radial plunger pump
EP0860607A3 (en) * 1997-02-25 1999-01-20 Sanden Corporation Suction and discharge valve mechanism for a compressor
EP0902212A2 (en) * 1997-09-11 1999-03-17 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP2113660A1 (en) 2008-04-30 2009-11-04 Ricoh Company, Ltd. Air Discharging Apparatus and Image Forming Apparatus

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE513561C (en) * 1929-01-17 1930-11-29 Gustav Schlick Seamless suspension body with circular, self-contained folds, especially for diaphragm pumps
GB707254A (en) * 1951-10-22 1954-04-14 Beacham Hydraulic Company Ltd Improvements in hydraulic pumps and motors
US2984223A (en) * 1959-11-27 1961-05-16 Budzich Tadeusz Fluid apparatus
FR2275662A1 (en) * 1974-06-19 1976-01-16 Leduc Gerard Swashplate type hydraulic pump with reciprocating pistons - has fluid entry through hollow end of main drive shaft
DE2431938A1 (en) * 1974-07-03 1976-01-22 Bosch Gmbh Robert Piston pump device with bore cut into piston - has sliding bolt in the axial piston aperture which slides under the influence of radial play

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE513561C (en) * 1929-01-17 1930-11-29 Gustav Schlick Seamless suspension body with circular, self-contained folds, especially for diaphragm pumps
GB707254A (en) * 1951-10-22 1954-04-14 Beacham Hydraulic Company Ltd Improvements in hydraulic pumps and motors
US2984223A (en) * 1959-11-27 1961-05-16 Budzich Tadeusz Fluid apparatus
FR2275662A1 (en) * 1974-06-19 1976-01-16 Leduc Gerard Swashplate type hydraulic pump with reciprocating pistons - has fluid entry through hollow end of main drive shaft
DE2431938A1 (en) * 1974-07-03 1976-01-22 Bosch Gmbh Robert Piston pump device with bore cut into piston - has sliding bolt in the axial piston aperture which slides under the influence of radial play

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL9400911A (en) * 1994-06-06 1996-01-02 Applied Power Inc Radial plunger pump
EP0860607A3 (en) * 1997-02-25 1999-01-20 Sanden Corporation Suction and discharge valve mechanism for a compressor
US6012905A (en) * 1997-02-25 2000-01-11 Sanden Corporation Suction and discharge valve mechanism for fluid displacement apparatus
EP0902212A2 (en) * 1997-09-11 1999-03-17 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP0902212A3 (en) * 1997-09-11 2000-07-26 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP1265007A2 (en) * 1997-09-11 2002-12-11 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP1267099A2 (en) * 1997-09-11 2002-12-18 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP1267099A3 (en) * 1997-09-11 2003-12-10 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP1265007A3 (en) * 1997-09-11 2003-12-10 Honda Giken Kogyo Kabushiki Kaisha Swash plate type continuously variable transmission
EP2113660A1 (en) 2008-04-30 2009-11-04 Ricoh Company, Ltd. Air Discharging Apparatus and Image Forming Apparatus
US8139973B2 (en) 2008-04-30 2012-03-20 Ricoh Company, Ltd. Air discharging apparatus and image forming apparatus

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