US3073275A - Control surface actuators - Google Patents

Control surface actuators Download PDF

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Publication number
US3073275A
US3073275A US5468A US546860A US3073275A US 3073275 A US3073275 A US 3073275A US 5468 A US5468 A US 5468A US 546860 A US546860 A US 546860A US 3073275 A US3073275 A US 3073275A
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Prior art keywords
motor
shaft
housing
hydraulic
supported
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Expired - Lifetime
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US5468A
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Fenzl Franz
Hinsch Karl
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Licentia Patent Verwaltungs GmbH
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Licentia Patent Verwaltungs GmbH
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63HMARINE PROPULSION OR STEERING
    • B63H25/00Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
    • B63H25/06Steering by rudders
    • B63H25/08Steering gear
    • B63H25/14Steering gear power assisted; power driven, i.e. using steering engine
    • B63H25/26Steering engines
    • B63H25/28Steering engines of fluid type

Definitions

  • the present invention relates to supporting arrangements for hydraulic actuator equipment for ships rudders or control surfaces of airplanes.
  • Hydraulic actuators are commonly used to control the positions of ships rudders or control surfaces of airplanes. These hydraulic actuators sometimes have transversely moving pistons which are disposed perpendicular to the rudder stock, or sometimes the pistons are annularly arranged around the rudder stock. Other arrangements include turning sash or rotary vane pistons.
  • the rudder stock serves as a carrier support for the complete hydraulic actuator equipment which may, for example, include an hydraulic motor such as a rotary vane motor or a turning sash motor or any other kind of motor in which pressure actuates one or more pistons while the piston movement is transformed into a rotary movement for driving the rudder stock.
  • the hydraulic motor itself supports and carries the pumping equipment, preferably electrically driven pumps arranged symmetrically about the rudder stock in axially parallel relationship thereto.
  • the assembly also carries the hydraulic-mechanical control means including a geared differential-servo motor and a control lever for the pump valves. This entire assembly including motor, pumps and control means, is carried by a shaft and is shock-mounted to the ships bull or to the planes body only rigidly enough to prevent angular displacement and possible axial shifting.
  • FIGURE 1 is an elevational view partially in cross section of the device shown in FIGURE 2, taken along the dash-dot line II thereof;
  • FIGURE 2 is a top view of hydraulic actuator equipment for a ships rudder
  • FIGURE 3 is half of a cross sectional view taken along line IIIIII of the equipment shown in FIGURE
  • FIGURE 4 shows the actuator unit in combination with a ships rudder
  • FIGURE 5 is a side half of the actuator unit
  • FIGURE 6 is a plan view, partly in section of the structure shown in FIGURE 5;
  • FIGURE 7 is a schematic showing of the hydraulic connection between the actuator unit and the pumps
  • FIGURE 8 is a fragmentary elevational view, partly in section of the control mechanism.
  • FIGURE 9 is a perspective view of a differential incorporated in the control mechanism.
  • Two electric pumping motors 2 and 2 are secured to the stationary part of a rotating vane motor 1 which motor, however, may alternatively be another kind of hydraulic motor.
  • the axes of the two pumping motors have a vertical position and they are symmetrically arranged about the vertical rotary stock 8 of a ships rudder or any other kind of control surface.
  • the housings of pumping motors 2 and 2 serve as supports for pumps 3 and 3, respectively, which pumps are capable of being continuously controlled.
  • the housings of pumps 3 and 3' are directly secured to the housings of the pump motors 2 and 2, respectively.
  • a housing 4 is supported on the stationary part of motor 1 which housing 4 contains the differential flow and feedback for the motor 1, i.e. controlling the output of the pumps.
  • Housing 4 supports a servomotor 5 acting to position the control levers 7, 7 of pumps 3, 3' respectively, via longitudinal rods 6, 6' respectively.
  • Levers 7 and 7 control the pump valves (not shown).
  • the preloading bushes 9 and 9 embrace the main bearing bolt 14 on top and at the bottom and are connected by the preloaded elastic sleeve to the stationary support 10 which is solidly fitted to the hull of the ship or plane.
  • the preloading bush 9 with its main bearing bolt is correspondingly secured to a stationary mount corresponding to the ship or plane. It will be appreciated that the coupling between preloading bushes 9 and 9' and stationary support 10 is not the main support for the pumping arrangement and the various motors, but it merely serves to block their rotary movements, or angular displacements, and also their vertical displacements.
  • the stock 8 is supported on a bearing 12 which is stationary and secured to the ships hull 13.
  • FIGURE 4 shows the control surface actuated described above in conjunction with a ships rudder 20 which is mounted for pivotal movement about the mounting shaft 21 and is in alignment with the screw 22.
  • the lower end of the rudder shaft 8 is angled and connected to the upper edge of the rudder 20.
  • FIGURES 5 and 6 are sectional side and plan views, respectively, of the left side of the actuator and show the hydraulic connections 23, 24, as Well as the details of the infinitely variable axial piston pump 3.
  • the connections are, for the sake of clarity, shown angularly displaced by 90, with FIGURE 6 illustrating the actual positions of the connections.
  • the connections 23, 24 communicate with upper and lower annular channels 25, 26, respectively, of the rotary vane motor 1.
  • the drive shaft of the pumping motor 2 is coupled to the drive shaft of the pump 3', as shown at 27.
  • the pump itself can be moved by the control lever 7 (not shown in FIGURE 5 which is connected to the rod 6 between the positions shown in solid and dotted lines.
  • FIGURE 7 shows, in schematic form, the connections between the pumps 3, 3' and the three pressure chambers of the rotary vane motor 1. As is shown in FIGURE 7, each of the two annular channels25, 26 communicates with each of three pressurechambers so that, depending on the setting of the pumps, the shaft 8 can be turned in either direction.
  • FIGURES 8 and 9 show the details of the differential 4 which carries the servomechanism 5, through which the position of the pump levers 7, 7 is adjusted.
  • the vertically positioned ser'vomotor 5 drives a bevel gear 30 by way of a two-part worm screw drive 31 and a planetary gearing 32.
  • the bevel gear 30 is in mesh with two bevelgears, one for each of the rods'6, 6, only the bevel gear 33 being shown in FIGURE 9.
  • This bevel gear is mounted on a shaft carrying a gear 34 meshing with a gear 35, the latter being mounted on a shaft carrying the link 36 to which the rod 6 (or 6') is pivotally connected. In this way, the pumps are brought out of the rest position in response to'the actuation of'the servojmo'tor 5.
  • An hydraulic actuator assembly for controllingthe position of a shaft supported on hearing means'fiXed to a vehicle body, comprising an hydraulic motor having a housing supported'on said shaft such that there may occur relative rotation between said shaft and housing, said motor including a rotatable motor member fixed to said shaft; bracket means connected with the vehicle body and coupled with said housing for preventing rotation of the latter with respect to the Vehicle body; hydraulic pressure-pump means supported on said housing and including conduit means leading to said motor; and valve means located in said conduit means for controlling the direction of rotation of said rotatable motor member.
  • said motor comprising a rotary vane motor carried coaxially on said shaft; said pressure pump means comprising at least two electric-motor-driven pumps symmetrically supported. on said housing; and said valve means comprising a valve having a control lever on each pump, and
  • shock-mount means coupling the bracket means and said housing.
  • valve means each having a control lever and controlling the admission of hydraulic pressure from the pump means into said motor to control its direction of rotation, and differential servo-motor control means connected with said valve levers by symmetrical linkage means.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)

Description

Jan. 15, 1963 F. FENZL ETAL CONTROL SURFACE ACTUATORS 4 Sheets-Sheet 1 Filed Jan. 29, 1960 m m e v r I 2 s ,2 k\\\\\\\\\ 'IIIIIIIIIIIL u M I a my Jan. 15, 1963 F. FENZL E'II'AL 3,073,275
CONTROL SURFACE ACTUATORS Filed Jan. 29, 1960 4 Sheets-Sheet 2 INVENTORS' Franz Fenzl 8 Kurl Hinsch )d wwr 4 1 71 ATTORNEYS Jan. 15, 1963 F. FENZL ETAL CONTROL SURFACE ACTUATORS Filed Jan. 29, 1960 lTw- I M I,
4 Sheets-Sheet 3 Fig. 5
INVENTORS Franz. Fgnll &
Karl Hmsch ATToRNEYs Jan. 15, 1963 F. FENZL ETAL CONTROL SURFACE ACTUATORS 4 Sheets-Sheet 4 Filed Jan. 29, 1960 mvemoas Franz Fenzl 8 Karl Hinsch ATTORNEYS Unite The present invention relates to supporting arrangements for hydraulic actuator equipment for ships rudders or control surfaces of airplanes.
Hydraulic actuators are commonly used to control the positions of ships rudders or control surfaces of airplanes. These hydraulic actuators sometimes have transversely moving pistons which are disposed perpendicular to the rudder stock, or sometimes the pistons are annularly arranged around the rudder stock. Other arrangements include turning sash or rotary vane pistons.
It is further known in many of these actuator systems to mount the actuators so that displacement and torque is produced between pistons and cylinders, or between vanes and vane-housings, when the stationary part thereof is secured to and carried by the ships hull and when the moving part is secured to the rudder stock. To improve these devices it is known to have the stock carry the hydraulic motor while a stationary portion thereof is secured against rotary displacement with respect to the ships hull. The pumping and control equipment for such arrangement is commonly secured to other stationary supports fixed to parts of the ships hull with conduits connecting them with the hydraulic motor. Such arrangements require considerable expenditure and space, particularly in view of the fact that the pumping means have to include two pumps for safety reasons. The conduits which are partially, i.e. at least at one of their ends, connected to the ships hull are subjected to vibrations of the hull and may be broken thereby.
It is an object of this invention to provide for a new and improved supporting arrangement for hydraulic actuator equipment for ships rudders or for plane control surfaces in which no strain may be set up between stationary and revolving or moving parts of the drive, whereby weight, space and expenditure is decreased as compared with the prior art arrangements.
According to one aspect of the invention in a preferred embodiment thereof the rudder stock serves as a carrier support for the complete hydraulic actuator equipment which may, for example, include an hydraulic motor such as a rotary vane motor or a turning sash motor or any other kind of motor in which pressure actuates one or more pistons while the piston movement is transformed into a rotary movement for driving the rudder stock. The hydraulic motor itself supports and carries the pumping equipment, preferably electrically driven pumps arranged symmetrically about the rudder stock in axially parallel relationship thereto. The assembly also carries the hydraulic-mechanical control means including a geared differential-servo motor and a control lever for the pump valves. This entire assembly including motor, pumps and control means, is carried by a shaft and is shock-mounted to the ships bull or to the planes body only rigidly enough to prevent angular displacement and possible axial shifting.
Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by Way of illustration only, since various changes and modifications within the spirit and States Patent scope of the invention will become apparent to those skilled in the art from this detailed description.
In the drawings:
FIGURE 1 is an elevational view partially in cross section of the device shown in FIGURE 2, taken along the dash-dot line II thereof;
FIGURE 2 is a top view of hydraulic actuator equipment for a ships rudder;
FIGURE 3 is half of a cross sectional view taken along line IIIIII of the equipment shown in FIGURE FIGURE 4 shows the actuator unit in combination with a ships rudder;
FIGURE 5 is a side half of the actuator unit;
FIGURE 6 is a plan view, partly in section of the structure shown in FIGURE 5;
FIGURE 7 is a schematic showing of the hydraulic connection between the actuator unit and the pumps;
FIGURE 8 is a fragmentary elevational view, partly in section of the control mechanism; and
FIGURE 9 is a perspective view of a differential incorporated in the control mechanism.
Two electric pumping motors 2 and 2 are secured to the stationary part of a rotating vane motor 1 which motor, however, may alternatively be another kind of hydraulic motor. The axes of the two pumping motors have a vertical position and they are symmetrically arranged about the vertical rotary stock 8 of a ships rudder or any other kind of control surface. The housings of pumping motors 2 and 2 serve as supports for pumps 3 and 3, respectively, which pumps are capable of being continuously controlled. In particular, the housings of pumps 3 and 3' are directly secured to the housings of the pump motors 2 and 2, respectively. The pumps elevational view, in section, of
are hydraulically connected to the chambers of the hydraulic motor 1 by means of pressure conduits.
A housing 4 is supported on the stationary part of motor 1 which housing 4 contains the differential flow and feedback for the motor 1, i.e. controlling the output of the pumps. Housing 4 supports a servomotor 5 acting to position the control levers 7, 7 of pumps 3, 3' respectively, via longitudinal rods 6, 6' respectively. Levers 7 and 7 control the pump valves (not shown).
The entire arrangement described thus far is rotatably mounted on and carried by the rudder stock 8.
In the flanges of the upper and lower motor casing part 1 there are bores where the main bearing bolt 14 with the two preloading bushes 9 and 9' are located. The preloading bushes 9 and 9 embrace the main bearing bolt 14 on top and at the bottom and are connected by the preloaded elastic sleeve to the stationary support 10 which is solidly fitted to the hull of the ship or plane.
The preloading bush 9 with its main bearing bolt is correspondingly secured to a stationary mount corresponding to the ship or plane. It will be appreciated that the coupling between preloading bushes 9 and 9' and stationary support 10 is not the main support for the pumping arrangement and the various motors, but it merely serves to block their rotary movements, or angular displacements, and also their vertical displacements.
The stock 8 is supported on a bearing 12 which is stationary and secured to the ships hull 13.
FIGURE 4 shows the control surface actuated described above in conjunction with a ships rudder 20 which is mounted for pivotal movement about the mounting shaft 21 and is in alignment with the screw 22. The lower end of the rudder shaft 8 is angled and connected to the upper edge of the rudder 20.
FIGURES 5 and 6 are sectional side and plan views, respectively, of the left side of the actuator and show the hydraulic connections 23, 24, as Well as the details of the infinitely variable axial piston pump 3. In FIGURE 5, the connections are, for the sake of clarity, shown angularly displaced by 90, with FIGURE 6 illustrating the actual positions of the connections. The connections 23, 24 communicate with upper and lower annular channels 25, 26, respectively, of the rotary vane motor 1. The drive shaft of the pumping motor 2 is coupled to the drive shaft of the pump 3', as shown at 27. The pump itself can be moved by the control lever 7 (not shown in FIGURE 5 which is connected to the rod 6 between the positions shown in solid and dotted lines.
FIGURE 7 shows, in schematic form, the connections between the pumps 3, 3' and the three pressure chambers of the rotary vane motor 1. As is shown in FIGURE 7, each of the two annular channels25, 26 communicates with each of three pressurechambers so that, depending on the setting of the pumps, the shaft 8 can be turned in either direction.
FIGURES 8 and 9 show the details of the differential 4 which carries the servomechanism 5, through which the position of the pump levers 7, 7 is adjusted. The vertically positioned ser'vomotor 5 drives a bevel gear 30 by way of a two-part worm screw drive 31 and a planetary gearing 32. The bevel gear 30 is in mesh with two bevelgears, one for each of the rods'6, 6, only the bevel gear 33 being shown in FIGURE 9. This bevel gear is mounted on a shaft carrying a gear 34 meshing with a gear 35, the latter being mounted on a shaft carrying the link 36 to which the rod 6 (or 6') is pivotally connected. In this way, the pumps are brought out of the rest position in response to'the actuation of'the servojmo'tor 5. As a result, one of thevannular channels 25,
26 'will be filled with a pressure fluid medium, thereby rotating'the vane in one or the otherdirection'. The rota'tion of the rudder will be transmitted to the lower one ofthe two sun gears which will cause the rods6, 6 and,.consequently, the pumpsi3, 3, to resume their rest position as soon as the desired rudder position, as determined by the servomotor 5, is attained.
We claim; V
1. An hydraulic actuator assembly for controllingthe position of a shaft supported on hearing means'fiXed to a vehicle body, comprising an hydraulic motor having a housing supported'on said shaft such that there may occur relative rotation between said shaft and housing, said motor including a rotatable motor member fixed to said shaft; bracket means connected with the vehicle body and coupled with said housing for preventing rotation of the latter with respect to the Vehicle body; hydraulic pressure-pump means supported on said housing and including conduit means leading to said motor; and valve means located in said conduit means for controlling the direction of rotation of said rotatable motor member.
2. In an actuator assembly as set forth in claim 1, said motorcomprising a rotary vane motor carried coaxially on said shaft; said pressure pump means comprising at least two electric-motor-driven pumps symmetrically supported. on said housing; and said valve means comprising a valve having a control lever on each pump, and
a linkage connecting said control levers for operating the latter in unison.
3. In an actuator assembly as set forth in claim 1, shock-mount means coupling the bracket means and said housing.
4. In an actuator assembly as set forth in claim 1, two
valve means each having a control lever and controlling the admission of hydraulic pressure from the pump means into said motor to control its direction of rotation, and differential servo-motor control means connected with said valve levers by symmetrical linkage means.
References Cited in the file of this patent

Claims (1)

1. AN HYDRAULIC ACTUATOR ASSEMBLY FOR CONTROLLING THE POSITION OF A SHAFT SUPPORTED ON BEARING MEANS FIXED TO A VEHICLE BODY, COMPRISING AN HYDRAULIC MOTOR HAVING A HOUSING SUPPORTED ON SAID SHAFT SUCH THAT THERE MAY OCCUR RELATIVE ROTATION BETWEEN SAID SHAFT AND HOUSING, SAID MOTOR INCLUDING A ROTATABLE MOTOR MEMBER FIXED TO SAID SHAFT; BRACKET MEANS CONNECTED WITH THE VEHICLE BODY AND COUPLED WITH SAID HOUSING FOR PREVENTING ROTATION OF THE LATTER WITH RESPECT TO THE VEHICLE BODY; HYDRAULIC PRESSURE-PUMP MEANS SUPPORTED ON SAID HOUSING AND INCLUDING CONDUIT MEANS LEADING TO SAID MOTOR; AND VALVE MEANS LOCATED IN SAID CONDUIT MEANS FOR CONTROLLING THE DIRECTION OF ROTATION OF SAID ROTATABLE MOTOR MEMBER.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3762356A (en) * 1968-06-06 1973-10-02 Allen Electric And Equip Co Steering mechanism for ships
US20040163386A1 (en) * 2003-02-21 2004-08-26 Moog Inc. Tandem electrohydrostatic actuator
US20080098942A1 (en) * 2006-10-26 2008-05-01 Northrop Grumman Systems Corporation Steering system and an associated vessel

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB173115A (en) * 1920-10-18 1921-12-29 Cottrell Corbett Wheeler Improvements in mechanism for hydraulically operating rudder stocks of ships
CH161914A (en) * 1932-03-24 1933-05-31 Oerlikon Maschf Actuating device working with hydraulic fluid.
US1974775A (en) * 1930-11-08 1934-09-25 Philip Dupre Hydraulic motor
US2019264A (en) * 1932-09-30 1935-10-29 American Eng Co Ltd Steering mechanism
US2340175A (en) * 1939-01-19 1944-01-25 Chance Britton Automatic steering
US2380596A (en) * 1941-05-21 1945-07-31 Western States Machine Co Torque control hydraulic clutch or coupling
US2449482A (en) * 1945-03-12 1948-09-14 Weatherhead Co Reversible pump controlled hydraulic cylinder system
DE893311C (en) * 1949-04-09 1953-10-15 Licentia Gmbh Hydraulic steering gear
US2746251A (en) * 1951-08-01 1956-05-22 Electrol Inc Self-contained power actuator
DE955031C (en) * 1954-12-07 1956-12-27 Licentia Gmbh Hydraulic rotary wing drive, especially for steering gear

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB173115A (en) * 1920-10-18 1921-12-29 Cottrell Corbett Wheeler Improvements in mechanism for hydraulically operating rudder stocks of ships
US1974775A (en) * 1930-11-08 1934-09-25 Philip Dupre Hydraulic motor
CH161914A (en) * 1932-03-24 1933-05-31 Oerlikon Maschf Actuating device working with hydraulic fluid.
US2019264A (en) * 1932-09-30 1935-10-29 American Eng Co Ltd Steering mechanism
US2340175A (en) * 1939-01-19 1944-01-25 Chance Britton Automatic steering
US2380596A (en) * 1941-05-21 1945-07-31 Western States Machine Co Torque control hydraulic clutch or coupling
US2449482A (en) * 1945-03-12 1948-09-14 Weatherhead Co Reversible pump controlled hydraulic cylinder system
DE893311C (en) * 1949-04-09 1953-10-15 Licentia Gmbh Hydraulic steering gear
US2746251A (en) * 1951-08-01 1956-05-22 Electrol Inc Self-contained power actuator
DE955031C (en) * 1954-12-07 1956-12-27 Licentia Gmbh Hydraulic rotary wing drive, especially for steering gear

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3762356A (en) * 1968-06-06 1973-10-02 Allen Electric And Equip Co Steering mechanism for ships
US20040163386A1 (en) * 2003-02-21 2004-08-26 Moog Inc. Tandem electrohydrostatic actuator
US6817067B2 (en) * 2003-02-21 2004-11-16 Moog Inc. Tandem electrohydrostatic actuator
US20080098942A1 (en) * 2006-10-26 2008-05-01 Northrop Grumman Systems Corporation Steering system and an associated vessel
US7418912B2 (en) * 2006-10-26 2008-09-02 Northrop Grumman Systems Corporation Steering system and an associated vessel

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