US1514537A - Electrohydraulic steering gear - Google Patents

Electrohydraulic steering gear Download PDF

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US1514537A
US1514537A US706710A US70671024A US1514537A US 1514537 A US1514537 A US 1514537A US 706710 A US706710 A US 706710A US 70671024 A US70671024 A US 70671024A US 1514537 A US1514537 A US 1514537A
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pump
crosshead
cylinders
rudder
cylinder
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US706710A
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Kriebel Percy Elmer
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American Engineering Co Ltd
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American Engineering Co Ltd
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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

  • a My invention relates to controlling apparatus and it has particular relation to electro-hydraulic steering systems.
  • One object of my invention is to provide a hydraulic motor of novel construction which is characterized by the absence of side-thrust guides, blocks, slippers and connecting links.
  • Another object of my invention is to pro- -vide, an electro-hydraulie steering system which is capable of installation in restricted spaces by reason of its compactness and general simplicity of desi n.
  • a further object o my invention 182130 provide a-- special form of connection be-- tween the hydraulic motor and the actuating pump which is so designed as to avoid leakage upon the operation of the hydraulic motor.
  • a hydraulic motor which comprises a pair of ramsand a pair of swiveled cylinders for said rams, the former being secured to the respective ends ofa rudder-crosshead.
  • variable-stroke'pump w ich may be driven by a continuously running electric motor.
  • the hydraulic "system may be maintained solid by means of a shuttle-valve which is operatively associated with the cylinders and asupply tankx
  • follow-up means is also provided for returning the reversing element of the variablestroke pump to its 'neutral'position when the rudder has moved through'a desired angle.
  • Fig. 1 is a top plan view ofv an electrohydraulic steering gear embodying' my in- Vention;
  • Fig. 2 is a-side elevational view ofthe structure of Fig. 1; and i Fig. 3' is a detail sectional view of the shuttle-valve.
  • a pair of hydraulic motors 1 and 2 comprising cylinders 3 and 4 and rams 5*and 6, respectively, are swivelly mounted by providing the former with upper and lower trunnions 77 and 8-8, respectively.
  • a bed-plate 9 is provided with pockets 10 for the reception of the lower trunnions 8-8, while the upper pair of trunnions 7-7 are journaled in bearings formed in a tie-piece 1-1.
  • outer ends of the rams 5' and 6 are ,pivotally secured to the respective ends of a ruddercrosshead 12 or other rotary or oscillatory structure by means of pins 13 and 14-, respectively, each pin being removably -secured to the ram by means of a set screw 15.
  • An actuating fluid say oil, may be supand 22 by means of clips 23 and 24: of usual design, respectively.
  • I. provide curved or coiled portions 26 and 27 immediately adjacent to the cylinder connection, so that the 'force incident to the turning movement of the fixed outer ends of the .pipes 18 and 19 are absorbed by the spring of the curved coil portions 26 and 27, respectively.
  • the reversible, variable-stroke pump 17 may be of the type, for instance, which is described in the patent to'Hele-Shaw and Martineau, No. 1,077,979, dated Nov. 11, 4
  • a pump of such type is provided with a control element (not shown) for determining the quantity as well as the direction-of #60 flow of the fluid through the flexible pipes 18 and 19',the arrangement being such that when the control element (notshown) is moved in one direction from a neutral position, say to the left, fluid is delivered under 3 while fluid neutral position,
  • the drum 34 constitutes a nut for a threaded shaft 35, which" is mounted for longitudinal movement in the pedestals 32 and 33.
  • a floating lever 36 is pivotally mounted midway its ends onthe outer end of the longitudinally movable control-rod 31. floating lever 36 has a sliding-block connection 37 with the end of the threaded shaft 35, while the other through a link 38 with a pivot pin 39 mounted on an adjacent outer end, of the rudder-crosshead 12.
  • I rovide a three-way surge valve 41 of usual design, as shown in Fig. 3.
  • This valve comprises a c lindrical casing 42 having a central chamber 43, which is connected by abpipe 44 to asupply tank 45 A formed in the plate 9, and it also comprises end-chambers 46 and 47.
  • the end chamber 46 is connected by means of pipes 48 and 49 with one side of the pump 17 while'the other end chamber 47 is connected by pipes 51v and 52 with the other side of the pump 17.
  • v p The chambers 4346 and 4347 are sepaextending annular flanges 53 and .54, respectively.
  • the flanges 53 and 54 constitute valve seats for a longitudinally slidable spindle 55 havin grooves 56 extending lengthwise thereo
  • the spindle 55 is further provided with valve disks 57 and 58 on the ends thereof, which are so constructed with relation to the valve, that when the tive and the rudder-crosshead 12 is brought 1nto its reverse position causes a reverse differences spindle 55 is in one extreme position it permits communication from the end chamber 47 to the central chamber 43 through the grooves 56, while communication is cut off between the other end chamber 46 and the.
  • the pump 17 may take up from the supply tank 45 a sufiicient quantity of fluid to keep the hydraulic system solid.
  • the connection between .the suction side of the hudraulic system and the suplpy tank 45 permits the excess discharge from the cylinder 3 to drain back into the supply tank 45 which, however, can be immediately recoveredupon the operation of the other cylinder. 4
  • I provide means whereby circulate from one cylinderto the other, said means comprising a valve-controlled pipe 58 which is c0nnected,respectively, to the pipes 49 and 52.
  • the openi-n of the valve 59 in the pipe 58 permits the uid, which is forced vout of one cylinder into the other, to pass freely around the pump 17 through the pipes 49,58 and 52..
  • a steering mechanism including a hydraulic motorone element of which is swiveled.
  • a movable element for actuating the same, a variable-stroke pump, flexible means for operatively associating said pump and said swiveled motor, and a continuously running electric motor for driving said'pump.
  • pivoted cylinder pivoted cylinder, a ram extending from said cylinder and operatively associated with said element, a Variable capacity pump, and flexible-means for-conducting the actuating fluid from said pump to said pivoted cylinder.
  • a .crosshead a pair of swiveled hydraulic motors foractuating the respective ends of said crosshead, a reversible variable-stroke pump, and fl exible pipes 'for operatively associating said pump, and motors.
  • the fluid in the hydraulic system may freely swiveled cylinders, rams for said cylindersoperatively associated with the respective ends of said crosshead, a variable-stroke pump for operating said motors, and flexible p1ping for operatively associating said pump and said cylinders.
  • a rud-- der-crosshead a pair of swiveled cylinders, rams for said cyl nders secured respectlvely to the ends of said crosshead, a varlablestroke pump, and flexible piping for operatively associating said pump and said cylin- 12.
  • a hydraulic steering In a hydraulic steering.
  • bearings for certain of said trunnions a tie-piece'providing bearin for the remaining trunnions, rams exten g from said 0 linders, a rudder crosshead secured to sai rams, and means operative to supply an actuating fluid to one of said cylinders.
  • a pair of cylinders provided with trunnions a bed-plate providing bearings for certain of said trunfor the nions, a tie-piece providing bear g from remaimng trunnions, rams exten said'cylinders, a'rudder-cro'sshea'd secured to sai rams, and means for supplying an actuating fluid to one oi said 0 linders and for simultaneously receivin t e discharge from the other of said cylin ers.
  • a hydraulic steering system'co prising a rudder-crosshead, a pair of swiveled hydraulic motors operatively associated with said rndder-crosshead, a pump for supplying an actuating fluid to one of said hydraulic motors and for receiving at least. a;
  • a variabletor, means or contro stroke131 havinga control element for 40 e dcrs and respectively secured'to the an s of 55 said rudder-crosshead, a reversible variable stroke pump, flexible piping for operatively' associating said reversible-pump and said cylinders, whereby actuati fluid ma be supplied to one cylinder an removed om the other, a supply tank, a shuttle-valve hav-v 1n sa l cylinders and said supply tank, whereby the excess discharge from one of said cylmders may be by-pass'ed to said suppl tank 85,
  • a controlelement forvarying the direction of operation of said pump, operating means for movin said control element from a neutral position to forward .or reverse positions, and follow-up mechanism actuated bysaid rudder-crosshead for returning the pnmp control element. from either of its forward or reverse post. 7 tions to its neutral position.

Description

' Nov. 4 1924- 1,514,537
P. E. KRIYEBEL ELECTROHYDRAULIC STEERING GEAR Filed April 15 1924 a Sheets-Sheet 1 Nov. 4, 1924.
, 1,514,537 P. E. KRIEBEL ELECTROHYDRAULIC STEERING GEAR Filed April 15 1924 2 Sheets-Sheet 2 Patented Nov. 4, 19.24.
PERCY ELMER KRIE BEL, O'F ATLANTIC CITY, NEW JIElRSEY, ASSIG'NOR TO AMERICAN ENGINEERING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A. CORPORATION or ramisxnvam annc'rnonvnnaomo srnmme GEAR.
1 Application filed April 15, 1924. Serial No, 706,710.
To all whom it may concern:
Be it known that I, -PERGY ELMER KRIE- BEL, a citizen of the United States, residing in Atlantic City, Atlantic County, New J ersey, have invented an Electrohydraulic Steering Gear,'of which the following is a specification.
A My invention relates to controlling apparatus and it has particular relation to electro-hydraulic steering systems.
One object of my invention is to provide a hydraulic motor of novel construction which is characterized by the absence of side-thrust guides, blocks, slippers and connecting links.
Another object of my invention is to pro- -vide, an electro-hydraulie steering system which is capable of installation in restricted spaces by reason of its compactness and general simplicity of desi n.
A further object o my invention 182130 provide a-- special form of connection be-- tween the hydraulic motor and the actuating pump which is so designed as to avoid leakage upon the operation of the hydraulic motor.
According to my invention, I provide a hydraulic motor, which comprises a pair of ramsand a pair of swiveled cylinders for said rams, the former being secured to the respective ends ofa rudder-crosshead. The
means of flexible pipin with a reversible,
variable-stroke'pump w ich may be driven by a continuously running electric motor. The hydraulic "system may be maintained solid by means of a shuttle-valve which is operatively associated with the cylinders and asupply tankx Follow-up means is also provided for returning the reversing element of the variablestroke pump to its 'neutral'position when the rudder has moved through'a desired angle.
With these and other objects and appli cations in mind, my invention further consists in the details of construction and op erationand arrangement hereinafter described and claimed and illustrated in the accompanying drawings, whereinc Fig. 1 is a top plan view ofv an electrohydraulic steering gear embodying' my in- Vention;
Fig. 2 is a-side elevational view ofthe structure of Fig. 1; and i Fig. 3' is a detail sectional view of the shuttle-valve.
In the illustrated form of embodiment, of my invention shown in the drawings, a pair of hydraulic motors 1 and 2 comprising cylinders 3 and 4 and rams 5*and 6, respectively, are swivelly mounted by providing the former with upper and lower trunnions 77 and 8-8, respectively. A bed-plate 9 is provided with pockets 10 for the reception of the lower trunnions 8-8, while the upper pair of trunnions 7-7 are journaled in bearings formed in a tie-piece 1-1. The
outer ends of the rams 5' and 6 are ,pivotally secured to the respective ends of a ruddercrosshead 12 or other rotary or oscillatory structure by means of pins 13 and 14-, respectively, each pin being removably -secured to the ram by means of a set screw 15.
- An actuating fluid, say oil,, may be supand 22 by means of clips 23 and 24: of usual design, respectively. In order to avoid the loosening of the connection between the outer ends of the pipes 18 and 19 and the cylinder clips 23 and 24 as the cylinders 3 and 4 are oscillated, I. provide curved or coiled portions 26 and 27 immediately adjacent to the cylinder connection, so that the 'force incident to the turning movement of the fixed outer ends of the .pipes 18 and 19 are absorbed by the spring of the curved coil portions 26 and 27, respectively.
- The reversible, variable-stroke pump 17 may be of the type, for instance, which is described in the patent to'Hele-Shaw and Martineau, No. 1,077,979, dated Nov. 11, 4
1913. A pump of such type is provided with a control element (not shown) for determining the quantity as well as the direction-of #60 flow of the fluid through the flexible pipes 18 and 19',the arrangement being such that when the control element (notshown) is moved in one direction from a neutral position, say to the left, fluid is delivered under 3 while fluid neutral position,
p relate;
pressure through the pipe 18' to the cylinder is substantially simultaneously drawn from the cylinder 4 into the ump 1 through the pipe 19. .However, w on said control element is moved to the right from a fluid is delivered through the'pipe 19 to the cylinder 4 and substanpump 17 is secured to ably mounted in spaced supporting pedestals 32 and 33, the latter a so providing a revolublemounting for a control drum 34.
a The control drum 34 is operatively associ= -der-crosshead 12 ated with a corresponding drum in the control station of the ship by means of a flexible wire rope (not shown). The drum 34 constitutes a nut for a threaded shaft 35, which" is mounted for longitudinal movement in the pedestals 32 and 33. A floating lever 36 is pivotally mounted midway its ends onthe outer end of the longitudinally movable control-rod 31. floating lever 36 has a sliding-block connection 37 with the end of the threaded shaft 35, while the other through a link 38 with a pivot pin 39 mounted on an adjacent outer end, of the rudder-crosshead 12.
When the control drum 34 is actuated in accordance with the movement of the co- 0 rating driving drum in the pilot house 0 the ship (not shown), the threaded shaft 35 is moved from the neutral 'tion shown in the to the left. .the midisnot in. motion at this time,the cross head 'pin39 is a fixed point about-whichthe floating lever 36' and the link thereb actuating shown ing of. one cylinder 38 are under the force of the outwardly moving threaded shaft 35. The resultiug lever" 36 causes a corresponding outwar movement of the pump control rod 31, the'control element (not of the reversible variable stroke pump 17. from its neutral position to an operating position, permitting the pump 17 to supply fluid under pressure through the pipe'18 to the cylinder 3 while simultaneously withdrawing-"the liquid from the cyl-.
inder 4 through the pipe 19, the gradual fill,
the other being substantially equal. The
. outward movement of the ram 5 and the inward movement of the ram 6' continues a so long as the drum 34 is rotated and the out offits neutral One end of the end thereof is connected in the cylinder displacement,
outward movement of the floating rated by a pair of inwardly and the discharge fromv other parts of the pump control element (not shown) is held position by the shdable control-rodBl.
e swinging movement of the cylinders 3 and 4, incident to the movement of the rudder-crosshead 1-2, is prevented frolrgloosemng the connection between the salts of the supply pipes 18 and 19 and their. respective cylinders by reason of-the flexible arrangement of the pipes 18. and 19, particularly the coiled 'portions'27 and 26 thereof.
When it is desired to stop the movement of the rudder-crosshead 12, the rotation of the drum 34 is discontinued whichqresult's in the slidin'g-blockconnection 37 becoming a fixed point for the linkage 36 and 38,
rather than the 39. Inasmuch as the i pump 17 is still livering fluid under pressure to the cylinder 3, causing the continued turning of the rudder-crosshead 12, the mo-' tion of the latter through the linkage 38 and 36 actuates the slidab e. control rod 31 inwardly until the reversing element (not s own) of the pump 17 is moved from its 0 crating position to its neutral position, whereupon the pump '17 becomes mopera to rest. A a
As mayreadily be seen, a further movenent of the control rod 31 by the drum '34 movement of the rudder-crosshead 12, such movement continuing until the drum 34 is brought to rest, Whereuponthe linkage 38 and 36 operates to return the pump control element (not shown) to its neutral osition.
While the fluid system, which inc udes the pump 17, the pi es 18 and 19 and the cylinders 3 and 4, w en once filled, is theoreti cally solid for all time, leaka es, for instance, due to slight mechanica require an automatlc replenishment from time to time. To this end, I rovide a three-way surge valve 41 of usual design, as shown in Fig. 3. This valve comprises a c lindrical casing 42 having a central chamber 43, which is connected by abpipe 44 to asupply tank 45 A formed in the plate 9, and it also comprises end-chambers 46 and 47. The end chamber 46 is connected by means of pipes 48 and 49 with one side of the pump 17 while'the other end chamber 47 is connected by pipes 51v and 52 with the other side of the pump 17. v p The chambers 4346 and 4347 are sepaextending annular flanges 53 and .54, respectively. The flanges 53 and 54 constitute valve seats for a longitudinally slidable spindle 55 havin grooves 56 extending lengthwise thereo The spindle 55 is further provided with valve disks 57 and 58 on the ends thereof, which are so constructed with relation to the valve, that when the tive and the rudder-crosshead 12 is brought 1nto its reverse position causes a reverse differences spindle 55 is in one extreme position it permits communication from the end chamber 47 to the central chamber 43 through the grooves 56, while communication is cut off between the other end chamber 46 and the.
central chamber 43. When the spindle 55 is in the other extreme position, communication is established between the end chamber 46 and thecentral chamber 43 through the groove 56, while communication be-- side of the pump. 17 is such that the valve disk 58 is moved into engagement with the annular flange 54 to interrupt the onnection between the end valve chambe 47 andthe central val've chamber 43. As eviously pointed out, the resulting moveme t of the valve spindle 55 actuates the'valve disk 57 out. of engagement with the annular flange 53, establishing a connection between the centralchamber43 and the end chamber 46.
Since the end chamber 46 is connected through the pipes 48 and 49 with the suction side of the hydraulic system, that is, the side of the pump 17 receiving fluid from the cylinder 3, and since the central chamber 43 is directly connected to the supply tank 45,-- the pump 17 may take up from the supply tank 45 a sufiicient quantity of fluid to keep the hydraulic system solid. The connection between .the suction side of the hudraulic system and the suplpy tank 45 permits the excess discharge from the cylinder 3 to drain back into the supply tank 45 which, however, can be immediately recoveredupon the operation of the other cylinder. 4
Should it become necessary to operate the rudder-crosshead 12 by means of the usual hand mechanism, I provide means whereby circulate from one cylinderto the other, said means comprising a valve-controlled pipe 58 which is c0nnected,respectively, to the pipes 49 and 52. The openi-n of the valve 59 in the pipe 58 permits the uid, which is forced vout of one cylinder into the other, to pass freely around the pump 17 through the pipes 49,58 and 52..
' While I have shown only one form of embodiment of my invention, for the purpose of describing the same and illustrating its principles of construction and operation, it is apparent that various changes and modifications may be made therein without departing from the spirit and scope of my invention. I desire, therefore, that only-such limitations shall be imposed thereon as are the above-described arrangement of ders.
demandedby'the prior art. Y
*Iclaim: v 1
. 1. A steering mechanism including a hydraulic motorone element of which is swiveled.
2. In combination, a swiveled hydraulic motor, and a variable-stroke pump for operating said motor.
3. In combination, a swiveled hydraulic motor, a variable-stroke pump, and a pipe operatively associating said pump and mo-' tor, said pipe having a flexible portion immediately adjacent to said motor.
4. In combination, a movable elementfa swiveled motor for actuating the same, a
pump for operating said motor, nd a conelectric motor for driving said pump.
6. In combination, a movable element, a swiveled motor for actuating the same, a variable-stroke pump, flexible means for operatively associating said pump and said swiveled motor, and a continuously running electric motor for driving said'pump.
' 7. In combinatlon, a vmovable element, a
pivoted cylinder, a ram extending from said cylinder and operatively associated with said element, a Variable capacity pump, and flexible-means for-conducting the actuating fluid from said pump to said pivoted cylinder.
8. In combination, a crosshead, a pair of indicated in the appended claims or as are swiveled hydraulic motors for actuating the respective endsof said crosshead, and a variable-stroke pump for operating said motors.
9. In combination, a .crosshead, a pair of swiveled hydraulic motors foractuating the respective ends of said crosshead, a reversible variable-stroke pump, and fl exible pipes 'for operatively associating said pump, and motors. y the fluid in the hydraulic system may freely swiveled cylinders, rams for said cylindersoperatively associated with the respective ends of said crosshead, a variable-stroke pump for operating said motors, and flexible p1ping for operatively associating said pump and said cylinders.
11.. In a hydraulic steeringsystem, a rud-- der-crosshead, a pair of swiveled cylinders, rams for said cyl nders secured respectlvely to the ends of said crosshead, a varlablestroke pump, and flexible piping for operatively associating said pump and said cylin- 12. In a hydraulic steering. system, the combination with a rudder-crosshead, of a pair of swiveled cylinders, rams for said cylinders secured respectively to the ends of 7 said crosshead, a reversible variable-stroke um flexible ipi for o eratively' assoiatiiig said pump h n d said ylinders, and a continuously operating motor for driving saidpump. I a 1 Y 13. In combination, a pair of cylinders provided with trunnions, a bed-plate providing. bearings for certain of said trunnions, a tie-piece'providing bearin for the remaining trunnions, rams exten g from said 0 linders, a rudder crosshead secured to sai rams, and means operative to supply an actuating fluid to one of said cylinders.
14. In combination, a pair of cylinders provided with trunnions a bed-plate providing bearings for certain of said trunfor the nions, a tie-piece providing bear g from remaimng trunnions, rams exten said'cylinders, a'rudder-cro'sshea'd secured to sai rams, and means for supplying an actuating fluid to one oi said 0 linders and for simultaneously receivin t e discharge from the other of said cylin ers.
15. A hydraulic steering system'co mprising a rudder-crosshead, a pair of swiveled hydraulic motors operatively associated with said rndder-crosshead, a pump for supplying an actuating fluid to one of said hydraulic motors and for receiving at least. a;
e other of portion of the discharge from t saidmotors, avsupply tank, a shuttle valve operable to permit the remaining portion of said discharge to pass into said-supply tank,
and means for driving said pump. I
16. In a hydraulic system of stee ng; t e combination with a rudder-'crosshead, of a pair of 'swiveled hydraulic motors, the ram elements of which are actively secured to the ends-of said cro ead, a variabletor, means or contro stroke puiplp havinga control element for 40 e dcrs and respectively secured'to the an s of 55 said rudder-crosshead, a reversible variable stroke pump, flexible piping for operatively' associating said reversible-pump and said cylinders, whereby actuati fluid ma be supplied to one cylinder an removed om the other, a supply tank, a shuttle-valve hav-v 1n sa l cylinders and said supply tank, whereby the excess discharge from one of said cylmders may be by-pass'ed to said suppl tank 85,
and also permitting the pump to e up such amounts of fluid as are necessary to keep the system solid, a controlelement forvarying the direction of operation of said pump, operating means for movin said control element from a neutral position to forward .or reverse positions, and follow-up mechanism actuated bysaid rudder-crosshead for returning the pnmp control element. from either of its forward or reverse post. 7 tions to its neutral position.
PERCY .Emmmmm.
an operative connection with each'of
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