DE2043775A1 - Hydraulic servo device - Google Patents

Description

% O 43 7 7.3.

Dr .-! Ng. H'λΝ3 RUSCHKE

Dipping. HcINZ AGULAR
• 5-fc / iLr _f ciie.ri S ^ Pienienoueistr. 2

Juiiatrand Corporation, Eocfcforcl, 111. (Y.St.A.)

"Hydraulic servo device"

Jie rorlie ₀ End invention relates to a hydraulic Üervovorrichtung, v / hich the delivery of Hochdruckflüjsi ^ izeit in a Menä; e can control which is proportional to a tflanuellen Zuführ.ist. Such a device is suitable for use in hydraulic circuits such as power steering controls at f.chv / er ^; Iti machines in which a given rotation of a lifter or other hand-operated part produces a supply of fluid to a hydraulic drive or cylinder, for example to steer the ground wheels. Such devices can be used to control the flow in any hydraulic circuit 3 in which precise adjustment of the amount of high pressure fluid to be delivered is required.

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In Λ er Ve ": ^ ^ n ^ enhe it v / uz-don various hydraulic controls -.ecohaffen, urn a cake st itnrc-1-3 Length of hydraulic fluid to 7er or sucher u as drives η and steering system stones to supply -yu . -One such hydraulic device is a pump in Ilor.t: - Nation with a single hand-operated valve. 1,3:. Such simple valves are required to be decided upon and experienced in the operation in order to ensure an effective adjustment of the flow . -eitsdruckeH and de .-;. · obtain current upright 2a addition requires a valve z \ i - i ue.iuelle Bev / Egan _£ s, ie, ur ;, de = valve in a first ilichtun ^ to open, and -ine, ura let the valve in a wide iiichi; uii _ö · su in order to supply a predetermined I.ienje of liquid.

Another. -Irt a hydraulic circuit to supply a predetermined one. Men _e 'e v of liquid systems au / ie steering devices is a hydraulic opeisekreis which "friickfabrunden" has uai the feed to end of liquid, v / conc vorbestiTnmte a movement of the associated actuator reaches v / is orden. Hydraulic recirculation systems, however, have the disadvantage that they require considerable torque in order to operate particularly on units of large displacement. The systems, which have a similar purpose and operate on a differential pressure control basis, are susceptible to erratic operation due to large changes in viscosity such as may be encountered during cranking in cold weather. Pressure differential controls are also not easily suitable for load-insensitive systems that

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before restricting their potential use *

It has also been suggested that a drive control can be achieved with a servo device, which a predetermined amount of liquid in accordance with the degree of movement of a manually controlled one Member feeds. This is the general nature of the present device. However, the devices * which were created for this purpose in the past, gear elements that are very expensive due to precise manufacture, and valves which also require considerable precision machining required. For these reasons, the known units are sensitive to a drop in performance caused by valve failure, namely because of the many sealing surfaces required. Furthermore, it is difficult to get high levels of liquid in these units Acid flow quantities while maintaining a small overall envelope.

The present invention overcomes the difficulties "in known fluid circuit systems by providing a hydraulic" servo device, the is easy to control to the instant release of a liquid flow at full pressure to prevent sudden changes in motion

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to prevent the associated drive and to reduce hydraulic shock forces in the lines and parts, as well as the associated servo valve to completely relieve hydraulic pressure, the device is load-sensitive or load-insensitive as required.

In particular, the present invention provides a hydraulic servo device for metering fluid under pressure, which has a manually operable device which is movable into positions which represent the desired amount of liquid to be delivered, wherein a servo valve device is brought into position by this manually operable device and the servo valve device Feed and load transfer devices, a relatively stationary, internally toothed outer tooth element, a carrier member that is rotatable on an axis, and at least one planetary gear that is rotatable is mounted on the carrier, and the axis of which is arranged at a distance from the axis of the carrier member, the planetary gear having external teeth which mesh with the internal teeth of the external gear stand and thus expanding and narrowing tooth gaps with relative rotation of the gears limited, the carrier member having a first passage means which is continuous with the communicating with another of the gaps, and having a second passage means which is continuous in conjunction with the other of the loopholes

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stands, the servovalve supply passage means optionally with the first and the second passage device is connectable in the] support member, wherein a .first load transfer device is optional with one of the passage devices in the support member is connectable and wherein a second load passage device is optionally connectable to the other passage device in the support member.

An advantage of the present invention is that the servo valve can be insensitive to load by Parts of sufficient length are provided so that if the servo valve is in a neutral position, the load passages in the servo valve from parts within the associated valve bore are blocked. In one embodiment of the present invention a load sensitive servo valve is shown in which the servo device responds to loads that act on the associated drive through appropriate Arrangement of the load passages in the servo valve so that they are partially in communication with the first and second passages in the carrier of the metering device stand. In this way the maintenance man can get through Maintaining the position of the ServoyentiXes of each external Load, which acts on the drive, so that every movement of the drive generates a corrective flow of fluid from the metering section of the hydraulic Device causes u & to move the drive back into its desired position.

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The invention is illustrated below using exemplary embodiments: explained in more detail using the attached drawings »

In the drawings show:

1 shows a plan view of a liquid control device,

Figo 2 is an enlarged longitudinal section of the hydraulic Device according to Figo 1,

Figo 3 is a sectional view along the line 3-3 in Fig =. 2, showing part of the servomotor in the hydraulic unit _f

4 is a cross-section along the line 4-4 in FIG. 1 showing the passages which cooperate with the servomotor ₉

FIG. 5 shows a sectional view along the line 5-5 in FIG. 4, the gallery passages being shown in the gear carrier which cooperates with the servo motor ,

Figure "6 is a cross section along the line 6-6 in Figure" 5 "wherein an arcuate passage shown! associated with a set of passages associated with the hydraulic servomotor

Figure 7 is a cross-sectional view taken along line 7-7 in Figure 5, showing another arcuate passageway which cooperates with the other set of passages in the servomotor;

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Figo 8 a different cross section of the carrier which is associated with the servo motor, wherein one of the two passages is shown, which cooperate with the servo motor to a tank passage _s

Figo 9 'shows another cross section of the support member Fig. 5 "and 8, both container passages shown are,

Figo Io is a partial view of the servo valve,

Fig «Tl a cross section of the servo valve along the line 11-1.1 in Pig * 2,

Fig. 12 shows a cross section of the servo valve along the line 12-12 in Pig »11,

13 is a broken sectional view of the servo valve along the line 13-13 in Fig. 12,

14 is a broken sectional view of the servo valve according to the line 14-14 in Fig. 12,

Fig. 15 is a sectional view of the interconnection between the servo valve and the servo motor according to line 15-15 in Figo 2

Fig. 16 shows the hydraulic mixing system in schematic form Figo 1-15, in which they are in a circle with a pump, a Drive and a container is shown,

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17 and 18 are sectional views of a modified form of the servo valve, which is load-sensitive

and

19 and 20 are sectional views of a further embodiment of the servo valve, with free flow provided by the pump, werji not the valve is in a neutral position,

As best shown in Figures 1 to 3, the hydraulic mixing system 1o generally consists of one manually rotatable input shaft 11, a rotatable servo valve 12 driven thereby, and a hydraulic one Servomotor or a metering device;? · 13ο

The generally opposite rectangular housing parts 15 and 16 are provided which _o The housing parts 15 and 16 is fixed a stationary ^ 2o cover internally toothed ring gear, which is more clearly shown in Figo 3 and the ring gear 2o together with the aid of suitable fastening elements 22, as is shown in Fig = 3 near the left end of the housing an annular end plate 24 is attached to the housing member by means of suitable fasteners 25 and has an axial flange 26 which is attached to a sleeve that supports the manually operated input shaft 11 surrounds "The housing part 15 has sprues 29 and 3o at its tapered portion 28" The sprue 29 has an inlet passage 31 which is connected to a source of pressurized liquid such as a

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Pump can be connected. In this context it should be understood that the present device is not technically as a pump or as a motor in normal Operating state is effective. The primary purpose is to get liquid under pressure from a source to obtain pressurized liquid and a predetermined amount of this liquid to one Give off drive. There is only a slight pressure drop in the hydraulic device 1 ο during their normal operation. The sprue 29 of the housing has a second passage 33, which is connected to one side of a drive (in Fig. 1 and not shown) which is in the form of a can be reciprocable piston cylinder connected to control a vehicle. Another passage 34 in the sprue 3o can over suitable lines are connected to the other side of the drive, to there hydraulic fluid to promote. A fourth passage 35 in the sprue can be connected to a container from which the pump connected to the passage 31 liquid pulls.

The servo motor 13 is generally composed of one annular gear assembly 38 rotatable in the Housing is stored. The carrier assembly 36 includes a left end cap portion 43 and a reohtes end cap portion

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-solder 44 a. A spacer 45 is arranged between the end parts 33 and 34, which is also shown in FIG. is shown. The end portions 43 and 44 and the spacer 45 are rotatable together as a unit attached by means of suitable fastening elements 48, which have threads.

The spacer 45 has four arcuate recesses 5o on its circumference, which are spaced from each other by 9o ° and between the end parts 43 and 44 limit pockets which receive planet gears 53, with the present hydraulic Device four planet gears 53 are arranged, although a greater or lesser number can be provided by planetary gears. The plate 45 also has convex arcuate surfaces 40 (Fig. 3), which have a small sealing space with the tips of the internally toothed wheel 2o and which also serve to close the servo device 13 within the housing parts 15 and 16 support.

Each planetary gear 43 has teeth meshing with the ring gear 2o, and each is rotatably supported in support assembly 38 by shaft 55 rotatably at one end in the end cap 43 in a bearing 56 and at the other end in the

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End section 44 is mounted in a bearing 56. the Gears "53 have a width that is slightly less than the width of the spacer 45 to one Running play for the gears 53 within the associated pockets in the gear carrier assembly create. When the gears 53 are in contact with the carrier rotate, limit which are engaged with each other Teeth expanding and constricting fluid slippers with the ring gear, and the present arrangement operates by carrying liquid to these expanding fluid chambers which cause the rotation of the gears 53, which set the gear carrier 38 in rotation.

To bring fluid to and from the expanding and contracting tooth gaps created by the interengaging gears 53 and 2o are limited, the end member 43 of the carrier assembly provided with two kidney-shaped passages 6o and 61 associated with each of the gears 53 are. The spacer 45 »the gears 2o and 53 seal with the sides of the end links 43 and 44 the Passages 6o from passages 61 so that each can act as a high or low pressure passage, and thus the servo or metering device is 13 reversible, and fluid can be pressurized to either the passage 33 or 34, as in Tig. 1 is shown.

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As shown in Fig. 5, the passages 6o are interconnected by axial passages 63 in the End part 43 connected, which are connected to a semicircular Galiried passage 64 in connection. An annular passage 64 is in communication with a valve bore 66 which is centrally located in the End link 43 is delimited by a passage 68, this is clearly shown in FIG.

In a similar way, the passages 61 (FIG. 5) are connected to one another via axial passages 69 in the end member 43 and an annular passage 71 in communication. The passage 71 stands with the valve bore 66 in connection via a diagonal passage 73, as clearly shown in FIG. Indeed, the passage 73 is angularly close and in the same transverse plane as the passage. The corresponding arrangement of the passages 68 and 73 is shown more clearly in FIG. The servo valve 12 performs the function of submerging liquid Pressure to one of the passages 68 and 73 and thus to the servo device 13 and supply liquid under Pressure from the servo device 13 to one of the passages 33> connected to the drive 34 until rule assembly 38 is given The servo device 13 traverses the angle of movement, following the movement of the valve 12 continues to rotate until valve 12 is manually

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is stopped, at which time the carrier arrangement 3'ä stops rotating and interrupts the flow through one of the passages 33, 34 connected to the drive.

The control valve 12 has a generally cylindrical construction, as shown in Fig. 2, To, 11, .12, 13, 14 and 15 and is rotatably arranged within the valve bore 66 in the end member 43.

As shown in Figures 2 and 15, means are provided to permit rotation of approximately 3o ° between the valve member 12 and the carrier 38 in each direction, from the neutral position of the elements to allow which in fig. 15 are shown.

In detail, the end of the valve hole has diametrically opposed social bolts 81 and 81, which upon rotation of the valve member 12 against the Bore 66 with an arcuate protrusion 83 in Engage coming from the end of the valve 12 extends and engages bolts 81 and 82. In-®er shown in Fig. 15 is the neutral position

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it is clear that the projection 83 rotated with the valve member 12 in each direction by approximately 30 ° can be before the with the bolts 81 and 82 comes into engagement. Another movement of the control valve 12 causes the carrier 38 to be driven by hand in this direction Failure of the pump that interacts with the hydraulic unit 1o, the operator by hand rotate the shaft 13, thereby causing the servo motor 13 to rotate by hand via the protrusion 83 so that the motor 13 acts as a pump and delivers liquid to the associated drive.

In order to resiliently press the control valve 12 into a neutral position with respect to the ¹ He ag he arrangement 38 and the passages 68 and 73, a central projection 83 extends from the end of the control valve 12. Through this projection extends a spring 87, which with its Is attached ends to the bolts 81 and 82, the spring 87 does not prevent a relative movement between the control valve 12 and the support assembly 38, but forces the elements into their corresponding neutral position, as shown in FIGS. 15 and 16 is shown. This is useful because the feedback effect of the servo motor 13 is somewhat short Q before its neutral position with respect to the servo valve 12 because of the relative arrangement between the co

w passages in the servo valve 12 and the carrier

■ ν, can be stopped. In the neutral position of the in

^ Figs. 1 to 16 are both * ^ Passages 68 and 73 from the parts of the control valve blocked, whereby the rotation of the carrier 38 is stopped under flow through one of the duro passages 33,34

out 'keilloohf-shaped manner he Hochdruckzuführdurchgang 86 is provided in the valve member 12 and Aveist a circular part or parts 88 and 89 aufe An axially extending portion 9o is provided to a freer Verbinduni (IGC 2 and 1o?); with the return flow passage, as an open central valve arrangement is provided, as shown in the embodiment according to FIGS. 19 and 20

For the purpose of supplying high pressure fluid to the high pressure passage 68 from passage 31, there is a self axially extending channel 94 is provided in the valve member 12, as shown in FIG. 2 o The channel 94 has a radially extending section 95 'which is connected to' a circumferential groove 97 which is also shown in Figc 1o, in turn in connection with the high pressure inlet recess 36 in the housing member 15 is related to «The recess 36 is continuously in connection with passage 31 »

TJm hydraulic fluid to and from the servo motor with regard to a drive that interacts with the passages 33 and 34, load passages' too and 1o1 of generally circular configuration on opposite sides of the and transverse coplaner with the main supply passage 86 J-n to the valve member 12 intended. The passage too is continuous with the passage 33 via an axially extending one Channel 1o3 and a recess 1o4 in the valve member in connection, which in turn with an annular Recess 1o6 in the gear housing member 15 (Figo 2) in understanding, which is connected to the passage 33 -

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In a similar way, the passage 1o1 is continuously connected to the drive passage 23 via an axial channel 1o9 and a recess 11 or the valve member 12, which is continuously connected to a recess 1o3 in the housing member 15 (FIG. 2). ? ¹ ... · stands, which on your part is in connection with the passage 34 ο The three valve passages 86, 1 oo uro 1o1 are separated from one another by the same angle, with the feed passage 86 between the}., Ϊ «the other one is arranged» The Servomotordurohgür.- _C ; e C -'- and 73 in the bore 66 are arranged so that the passage 68 is in the middle between the passage <: ^ and the passage 1oo, and the passage 73 is in the middle between the Passage 86 and the Durchgar.j 1o1 when the valve slide 12 is in its neutral ".... position according to FIG. 16

Two slots 112 and 113 (see Figures 2, 8, 9 and 16) extend radially outward from the circular bore 66 of the servo device 13 and stenen in connection with the annular space 114 between the carrier 33 and the housing parts 15 »16o These recesses are like this arranged that the load channel 1oo in the middle between the recess 112 and the passage 68 and the load channel 1o1 in the middle between the recess 113 and the Passage 73 is when the servo valve was in the neutral position

The interior of the casing communicates directly with the return passage 35 in communication so that fluid flows therefrom to a suitable container 115 shown in FIG 16 ₀

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ζ3 ± £ · 'ζ is. The recesses. 112 and 113 serve to convey liquid from the contracting side of the associated drive, which liquid flowed into the device through one of the passages 33, 34 aum container 115

The control valve 12 is pressure-balanced by recesses 12o, 121 and 122 in the valve bore 66 , are arranged coplanar with and diametrically opposite the passages 1oo, 86 and toi - "like .this" -in? Ig _o 12. The recesses 12o, 121 and 122 have the same surface area as the passages too, 86 and 1o1 and are fed with high-pressure fluid through generally radially extending passages 123, 124 and 125 which are in communication with the passages lying opposite lu ^ V 125 are shown more clearly in Figs. 13 and 14, respectively, and it can be seen that they are arranged approximately diagonally, so that the channels 123, 124, 125 do not meet with one another without deciding so are equal and opposite hydraulic Reactions imposed on the control valve 12 within the bore 66, the valve member being hydraulically balanced -

In general, each of the passages in valve member 12 and the passages in end member 43 are circumferential at a distance from each other by small sealing ribs arranged around different types of control too obtained, various modifications shown in Figs. 17 to 20 will be described below

So that the liquid can circulate from the space 114 to the feed channel 94 when the servo device as Standby pump is used, a shut-off valve

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arrangement 126 in the valve slide 12 provided as this is shown in Figo 2. The shut-off valve 126 prevents however, that liquid can flow from the supply channel 94 to the space 114 when the pressure in the supply channel 94 is higher, what is generally the case.

While the operation of the embodiment according to FIGS. 1 to 15 should be clear from the above description, the following is a summary of the operation of the device on the basis of the schematic representation ± r. 16. Assuming that a pump 128 feeds pressurized fluid to passage 31 and a container 115 is connected to passage 35, passages 33 and 34 are connected to a hydraulic drive 13o as if it were a double acting cylinder further assume that when the passage 34 is pressurized there will be an effect which may be termed left-handed. Similarly, when the passage 33 is pressurized, a right-hand function will occur

Y / enn by turning the Y-valve 12 either the passage 68 or passage 73 is connected to the source of pressurized liquid and the other passage is connected to the hydraulic load 13o, an equal pressure becomes in every line except one very little loss due to the friction in the servo 13 developed. Assuming that the hydraulic pressure is sufficient to affect the drive Overcome the applied load and the liquid will moved by the servo device 13 so that the latter is rotated o

BATH ORIGINAL

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j '; ann flows out the liquid from the opposite Channel with the same pressure as it enters or "±? Ίΐ we borrowed. ·: With the same DrjclCo 7 / enn of Zu-TU.hr Print in the openings or passages 68, 73 ν-ir build en iet, wii-i the flow in. the opposite ™ cot ;? direction, which causes that sicli the device 13 in a reversed Direction turned

. "Jeim to ^J as Yentilglied 12 c is in the neutral position by ± 'i 16 ciiid, blocking all passages ui.d the Hcjh-äruckein ^ angsdurchgang 31 and the flow rsura 2ufül- rdurchgan ^ ^; 86 in the valve is Hydraulic fluid under pressure blocked by the circular bore 66 of the servo-valve also enters the pushbutton 121 , which is located radially opposite the passage 86, so that the slide is hydraulically balanced

At the same time, the passages 1oo and 1o1 are through the circular solucung blocked so any load that occurs at the drive 15o, is countered by an adequate amount of pressure in the lines connected to the passages 33 and 54 are connected, ο Many times the can Do not move servo because passages 68 and 73 are blocked by the slide 12. From these The reason is that described with reference to FIGS hydraulic circuit a closed and not load-sensitive

Assuming that the slide 12 is rotated counterclockwise by hand by a small amount

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(v / ie is inclined in Pig »16) that the / Suführdurchgai-r ^ C- rait is connected to the 'passage 73, the Duro': juj 68 is in connection with the load passage 100 on the same side. High pressure fluid thus becomes the servo device 13 drive clockwise so that the servo valve ^; ' ^1. ! · ■■ '43 «em valve member 12 follows, and at the same time pressurize passage 68, with pressurized fluid flowing through the passage. 1oo is released from the main passage 33 to the left side of the drive 13o and it is driven to the right v / ird ₀ Since the passage 1co is under pressure at this time, the pressure compensation recess 12o is also under pressure and keeps the slide in hydraulic compensation,

If the servo device 13 rotates, it will move of drive 113 to continue to the right, and liquid from the low-pressure side of the drive v / ird through the passage 34 in the housing 15> Passage 1o1 in valve member 12, recess 113 in end cap 43 to flow back to the container through passage 35 in the housing?

When the movement of the control input member 11 is stopped, the rotation of the servo device 13 may cause that the servo part 43 connects to the link 12 and that all passages are in their original Move back to the neutral position and thus the displacement of hydraulic fluid out of the passage 33 stops »However, the real position of the controller 11 of the servo device 13 in the hydraulic drive changed over a certain amount »It can therefore be understood that a further rotation of the hand of the Input member 11 causes the servo device to continue rotating and more fluid under pressure to the Drive 13o is delivered «

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: When the slide 12 is rotated in the opposite direction, a quantity of pressure fluid is passed over the passage 34 to the right of the drive 3o, 13o, in order to have a left-hand action At this time, liquid at low pressure will flow back from the left side of the drive to the passage 33 and the container through the passage 100 and the recess 112 _e

Since small sealing ribs between the different Durchf-p.njen.in the servo valve 12 and the passages in the support member 38. are provided, avoid the Dic-htrippe.1 the total rotation of the servo device 13, which is required to complete the servo device 13 to.'iiiglii'ili deo servo valves 12 in one neutral position The spring 87 shown in Fig. 1 5 creates its mechanical restoration of the small Complete the distance to the neutral position ο

The circuit described above is a load-insensitive system, since loads given to the drive 13o do not affect the operation of the hydraulic device 1o. In accordance with the servo valve shown in FIGS load-sensitive system can be made in which a load which is applied from the outside is ο "sensed" by the hydraulic unit 1 and thereby a "feedback" is obtained to the operator ο V / ie iii-IJi ^ 17 and 18 are shown, vilrd by providing voa Duccrigai'ig extensions 1oo a ¹ and 1o1 a · the hydraulic device 1o, if desired, load-sensitive »

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The passages 1oo a ¹ and 1o1 a ¹ are of sufficient length so that when the valve 12 is its neutral tip as shown in FIG. 18, the passages 1oo ^! and 1o1 · are connected to the Seryoniotordurehgangen 68 ¹ and 73 ' _β This effectively switches off the neutral seal between these passages "Since the passages 1oo · and 1o1 * are directly connected to both sides of the associated drive and the openings 68" and 73 'of the inlet-outlet for the Servovorri ^v :: ~ tung 13 are, when the actuator is moved by an external load, the servo is driven against the direction 13, the servo device 13 is mechanically coupled to the mechanical control by the spring 87'

If there is no resistance to movement of the input element 11 caused by the operator, any external load on the drive will cause liquid to enter one of the passages 33> 44 through the servo device 13 and back to the opposite side of the drive flows «The leaf spring becomes a convenient alignment between the slide 12 and the servo device Hold 13 upright during this rotation and at the same time rotate the input shaft accordingly 11 cause *. However, the rotation speed is due to of the small fluid channels that exist between the various passages »The operation the pump has no effect at this time as the passage 86 remains blocked.

Under these circumstances, however, if the operator opposes the rotation of the input shaft 12, caused by the "feedback effect" will cause a slight movement of this drive, that the servo device 13 hydraiilisiih of the

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separately and with the pump via passage S6! verbund ei: v-will result from the helative rotation between "the cap 43 and the member 12 resulting liquid is thus driven in one direction, impure movement by the external load to 'v.'ld. stand * ■■■ -: ■■ .. - - - .'- _.:

l-jijie further modification of the servo valve es- is in Figo. and 2o shown In this embodiment, a valve 12 "is provided ,, which is in size and construction equal to the valve 12 except dal? it open in ivt dor llitte by providing a recess 15o ', that in the recesses between the Lütte 112 "and 113" is arranged when the valve member 12 "is in the neutral position, as shown in -Figo 2o, the supply passage 86" is freely in communication with the recess 15o. In this connection, liquid is discharged of the pump is fed back directly to the tank when the valve 12 "is in the neutral position» With this type of circuit, pumps of different volumes are not required and pumps of fixed volume can be used as they can pump continuously at low pressure in the middle of the open valve this is possible and the expenditure of energy under idle conditions is kept to a minimum

It should be understood that the recess should be located 15o so that when the valve is rotated from its neutral position to a working position, as shown in Figo 19, the recess 15o sealed 12 ^K of the ribs on the Vehtilglieä *: ν. :. -. : -.-.. - .-

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Claims (9)

Claims (1. ) J Hydraulic servo device for measuring fluid under pressure, with a manually operable device which is movable in positions which indicate the desired amount of fluid to be delivered, a servo valve device which is brought into position by the manually operable device is, wherein this servo valve device comprises feed and load transfer devices, a relatively stationary, internally toothed outer gear member, a carrier member which is rotatable about an axis, and at least one planetary gear which is rotatably mounted on this carrier and has an axis which is from the axis des-carrier member is arranged at a distance, wherein the planetary gear has outer teeth which are in engagement with the inner teeth of the outer gear and thus limit expanding and contracting gears during relative movement of the gears, characterized in that the carrier member with a first through device v can be seen which is continuously in communication with one of the gaps, that a second passage means is continuously in communication with the other of these gaps, that the servo valve feed passage means is selectively connectable to the first and second passage means in the carrier member, that 'a first load passage means - 109830 / 1U1 BATH ORIGINAL treatment - optionally with one of the through facilities is connectable in the support member, and that a second load transfer device is optional with the other Through device connectable in the carrier member 2.) Door direction according to claim 1, characterized in that that the carrier member has a centrally arranged bore, that the bore has a first through opening having 'which is in "communication with the first passage means, and that a second A through opening is provided which is in communication with the second through-passage means that the servo valve means includes a cylindrical member which is rotatably supported for limited rotational movement in this bore, and that the feed passage means and the first and the second load passage device in this cylindrical Member are limited and are optionally connectable to the first and second openings. 3.) Device according to claim 2, characterized in that the feed passage device and the first and. twelve; i. Lo Lir tdurchgfin. ^. 'E Inr i tung- in a plane q-ue.r to d'Ti! z'j I. -ίην rifjchen, Jorvov-nfcilglif-d lie. 10 9.830 / 11 Λ 1 4 ·) Device according to claim 1, characterized in that a plurality of gear wheels are provided which are rotatably supported on the support member and have external teeth which are in mesh with the teeth of the outer gear. 5.) Device according to claim 1, characterized in that each of the feed passage means the first load passage device and the second load passage device have a through opening on the The scope of the valve device comprises that the valve device is a cylindrical valve member and comprises means to reduce the force of the fluid pressure on the valve member in each of the through openings balance. 6.) Device according to claim 5, characterized in that the compensating device is a pocket at the periphery of the valve member opposite each of the through openings, and that a device is provided, which a connection between the through openings and the opposite Bag creates. 7.) Device according to claim 1, characterized in that that the first and second load 109830/1 U1 BADORTOlNAL gear device are connected to drive a load in any direction of movement that the oexvo valve member movable into a neutral position is in which the feed passage means except in connection with the first and the second Is passage means in the support member, and that the first and the second load passage means are arranged in the valve means are that they are at least partially related to the first and the second paging device in the carrier member are in communication when the valve device is in the neutral position. 8.) Apparatus according to claim 7, characterized by a pump for supplying pressurized liquid to the supply passage means, a liquid drive, a first line means which connects one of the load passage means to one side of the drive, and by a second line means which connects the other of the Load transfer device connects the other side of the drive, 9.) Device according to claim 1, characterized in that the carrier member has a return passage between the first and the second passage comprises a ring, and that the feed passage can be connected to the return passage if, the servo valve device is in a neutral position. 109830/1 UI ι * L e r s e i t e