US1752022A - Means for actuating steering gear and for analogous purposes - Google Patents

Description

S. D. OLSEN March 25, 1930.

MEANS FOR ACTUATING STEERING GEAR AND FOR ANALOGOUS PURPOSES Filed Jan. 12, 1925 2 Sheets-Sheet l lnulllll I I l l l1 s. D. OLSEN 1,752,022

MEANS FOR ACTUATING STEERING GEAR AND FOR ANALOGOUS PURPOSES March 25, 1930.

Filed Jan. 12, 1925 2 Sheets-Sheet 2 25 waste.

i Patented Mar. 25, 1930 SIMON DOKK OLSEN, OF WALTHAMSTOW, ENGLAND MEANS FOR ACTUATING STEERING GEAR AND FOR ANALOGOUS PURPOSES Application filed January 12, 1925, Serial No.

This invention has reference to hydraulic or like transmission systems, and is applicable to ships steering gear and to analogous purposes, such as the working of turrets or dock '5 gates for instance.

A feature of the invention is that the rudder post (or the like) is operated through the medium of rams or plungers acting on a cam in such a way that only true rotary or turning forces are applied to the rudder post, whereby all sidewise or lateral pressure or strains are reduced or avoided altogether. In addition to this the cam permits of the force being varied for different positions of the rudder .15 or other apparatus, according to the resistance at that particular position, and is always ready to start instantly when required.

The hydraulic transmission comprises a system in which the working pressure is generated by a continuously running pump combined with a high pressure accumulator and arranged in a closed circuit comprising the rams and a control valve, so that the exhaustis returned to the pump instead of going to To this end the low-pressure side of the system comprises a reservoir arrangement of the air-bottle type for instance) in which the exhaust can accumulate ready to be repumped back gradually to the high-pressure side. This reservoir is connected with the pump through a loaded non-return valve.

This system enables a small motor running continuously to deal with a load which would otherwise require a much larger motor, and is always ready to start instantly under the maximum pressure, whilst being constantly held when at rest without any play or backlash. Inthe accompanying diagrammatic drawmgs:

Fig. 1 is a general view of a hydraulic steering gear according to the view.

Fig. 2 is a development of the edge cam by which the rudder is operated. a

Fig. 3 is a part sectional view through the cam, rollers and one of the cylinders. According to this example, the cam is formed by a semi-circular turret or segmental cylindrical piece a standing onedge on 0 rollers (such as b) or the like, and connected 1 ,908, and in Great Britain January 24, 1924.

The thrust against one slope of the cam serves to impart the required motion to the rudder in one direction, whilst the thrust against the other half or slope of the cam serves for the opposite directlon.

The movements of the cam a will be clear from Fig. 2 in which a and a represent the extreme or hard-over positions of the bottom point or angle of the cam, a representing of course the position of this angle when the rudder is amidships and the rollers e are in the middle of the cam slopes.

The contour of each half or slope cl (Z1 of the cam may be so shaped as to give the desired graduations in force or range of movement above referred to. The shape shown in full lines in Fig. 2 is very suitable for ordinary steering purposes. It differs only slightly from the theoretical shapesee dotted lines'to avoid having a flat surface under the roller in the midway position.

The rollers b on which the cam a rests serve to resist or take up any of the endwise thrust or downward pressure from the rams which is not converted into circular motion by the cam, instead of such thrust being transmitted to the rudder post. The axles of these rollers rest in bearings 6 carried by the base plate 5 of the apparatus.

Thus lateral or bending strains on the rudder post 0 are obviated, and the only force which is applied thereto is the actual torque or turning movement of the cam.

In the normal position (as when in the case of a rudder the latter is directly amidships and therefore not acting) the ram rollers press on the middle of each slope or cam curve d (Z the rams f themselves being approximately at right angles to the average slope of the two sides of the V-cam, so that they converge upwardly. The ram cylinders a, in the; well known way.

friction rollers 25, instead ofbeing in a direct axial line with the cylinders f are placed a little further apart so as to be slightly out i of e x c l ne of th u t.- Te h s n e b st.

resultsthe cam slopes Z. (l instead of being straight have. the r ower hal es mad sl ght y bulging or: convex, whilst theu-pper halves are sligtly lQCBSSeClor concave, as shown inEig. 2.

his; d ag am qo r spe s the. movement Q e09 on. ea h. id f th mld-sh p pe iti n i he rud e z- The the et c l h p s sh w in dotted lines, but this gives an almosthorizontal bearing surface immediately under the roller at the middle point on either side. The full line position is therefore preferred in pra ice, ereby he urfa e at h m d l point is brought somewhat more nearly nor? mat to he, hr st, and t us tarting in either direction. is facilitated.

The hydraulic pump his connected with the flow and return pipes 71 is which a e pro,-.

vided. with air-bottles or accumulators], m, of which there may be one or moreto. each pipe. The admission of the-power-transmittingmedium on liquid, (oil or water). to the rams. is regulated by any suitable form of COIllZhOlLVfilVQ n and following-up or hunting valve gear a operated by thesteering Wheel 0.- and mesh' -g. with a, rack pen. the cam body Or the valve, n may be operated by suitable connections from t rudder: Pe n ny other c n enien in anner; I. Th svel in urn s conn ted w h the erms by pipesi and k 1 In the. xampl show it. s Pi$ 0l1 lv s and; is ither ubular 0r hesop n Pas ages connecting he paces, at. the. top and bottom. of its: cylinder- It is, saa g ehg d Pasties the P 96; i

that; in; its; upper n s muse ro itien connected with 11 both. and; is? just shgh-tly area .se a to alsooonnestwithi; and (3 tslowest Be sition, only It is: eOmwfillfld at th piss being then open .to. exhaus th'mllghi lighte of the Valve and the ipe Thealatter pipe isfconstantlyopen and is in fact Qll=$id the. .movementof the valve.

The. pump 7 electric or other motor; 9. The.return flow,

through lb back into the pump. is; controlled;

a ans r ches wa r loaded to gi a sli 'ghtjresistanoe (sayhal'fjan atmosphere).

hv "s GlIhVBIL continucusly by V orpressureg eservoir1,; hilst' harr g to the re-entry of the liquid into the pump chamber from the exhaust reservoir or airbottle m in which it first collects. This exhaust accumulator we may be arranged for working at about atmospheric pressure and below the same. From the pump the liquid is forced, through another ordinary non-return valvem up into the main accumulator Z on the high-pressure or delivery side i of the system again, where it may be stored up for .the nextoperation.

In connection with this, it may be mentioned that any air which may get into the system, is carried round by the circulation and ultimately collects in the main reservoir or airsbottle, and thus any risk, of trouble with air-blocksv in the pipes is entirely avoided;

' In. the pipe i may be provided a relief-valve i and to the return 1 e is a feed reservoir 9 s v I be connected to make up for small may losses,

The working pressure may be varied; by these arrangements, that is, raised or lowered by admitting working fluid to or releasing L,

same from the system.

It will be understood that owingtothe action of the main accumulator, the rams are always kept tight down on, to the two cam edges, thus holding the cam. positively without shake or backlash. I

When the system is idle, the pump. goes on drawing liquid from the exhaust reservoir m until, owing to the reduction of pressure therein and the action of the non-return valve q. loaded as just mentioned, the counter re sistance is more than the normal suction of the pump (about one atmosphere) can overcome. The pump therefore simply begins to run idly. Immediatelyhowever that owing tothe reworking of the system, the counterpressure or, partial-vacuum in the exhaust steady reservoir m isrelieved, the pump is able to again take liquid in from the returnsidela and pump it back into the pressure or deliv: ery side i. pump. is automatic and it can at a practically constant: speed without requiringregulation or attention, whilst as. it can go on storing up pressure or motive liquid n. ur g erm. is id e, a mesh smaller pump a d mot will suffice than would otherwise be necessary; .Moreever a tullsupply of motive liquid at a maximum pressure is available always to. start-the em 'fi instant y h t h ye 'v gear n ismojved, instead ot the pump having e'hsgin at. that menisn t bu d-up h me sure. r v

When the d r' e th midwa-y PO t Q and the. valve is ai ed ate he pos tieh h wn in Figs. 1,. le t ha d. are f 00. nested through th pipes i? end tethe ta a ram. is. connected; threngh he raises Thus the delivery action of the be set to. run

. .15 the n er al th t the sysf to exhaust reservoir m. Thus the left-hand roller 6 is forced downwards and moves the turret cam a towards the left, so operating the rudder. The roller of the right hand cam at the same time is moved upwards by the upper right hand portion of the cam as the latter swings round, this movement being permitted by the escape of the working fluid through the valve to the exhaust reservoir. lVhen the desired position of the rudder is reached, the valve moves into its middle position, in which both pipes 2' and 71: are just barely open so that pressure from the pipe 2' can act on both rams and hold the rollers and the rest of the arrangement steady and without any backlash or play, as mentioned.

When the rudder is to be moved the opposite Way, the valve is lowered until the left-hand ram can exhaust through its pipe 2' into the top of the valve chamber and through the body of the valve a (which is tubular as stated) into the exhaust pipe is. The pipe 70 at this time is fully open to the supply pipe 2' and the full pressure comes on the right-hand cam. As the exhaust pipe is constantly open, the valve does not need to cover it. It will be seen also that the pipe z is always more or less open through the valve itself, and either in communication with 2' or 70 or with both, as above explained, according as the rudder is moving or is stationary.

Instead of being applied simply to moving rudders the arrangement may be employed for moving other heavy loads such as gun turrets or dock gates for instance, and for other purposes where reliable transmission of an analogous kind may be desired.

Obviously the above arrangements may be modified in various ways in carrying the invention into practice without departin from the general nature thereof. Thus instead of the cam being semi-circular in shape, it might be a complete ring or turret with the cam slopes and rams duplicated at opposite sides.

I claim:

1. Means for operating ships steering gear and for analogous purposes, comprising a shaft to which onlya partial turn is to be given, a segmental cylindrical cam co-aXially mounted on said shaft, such cam resting on one edge and having a V-shaped cam-like part at its other edge, stationary hydraulic rams exerting their thrusts on opposite sides of said recess, substantially as described.

2. Means for operating ships steering gear and for analogous purposes, comprising a shaft to which only a partial turn is to be given, a segmental cylindrical cam co-axially mounted on said shaft, such cam resting on one edge and having a V-shaped cam-like recess in its other edge, stationary hydraulic rams exerting their thrusts on opposite sides of said recess, valves for controlling the action of said rams and gearing between the cylindrical cam and said valves for controlling the latter, substantially as described.

3. Means for operating ships steering gear and for analogous purposes, comprising a segmental cam with a V-shaped cam-like part at one edge, stationary hydraulic rams acting counter to each other on opposite sides of said part, and a valve arrangement which in its intermediate position keeps both rams under pressure, substantially as described.

4-. A motor arrangement for operating ships steering gear and for analogous purposes, where a very powerful but only partlyrotary movement is required, comprising a turret-like segmental cylindrical cam mounted on the shaft which is to be turned and co-axial therewith, said cam having two oppositely inclined cam-slopes forming a wideangled V-shaped gap in one of its edges, the other edge being flat to serve as the supporting edge, and stationary inclined hydraulic rams situated at said recess and acting counter to each other on the opposite cam slopes in a direction towards the supporting de vices, substantially as described.

5. A motor for operating ships steering gear and for analogous purposes, comprising a shaft, a turret-like edge-cam carried by said shaft, such cam being formed by a segment of a cylinder having oppositely inclined cam slopes forming a wide-angled V-shaped recess in its upper edge and said segmental cam being co-axial with the shaft to be moved, inclined hydraulic rams situated in the V-shaped recess and acting on the oppositely-inclined slopes of said cam, said rams straddling the cam and having slots through which the cam-edges can move, and means for supporting the cam at its opposite edge so that it can travel freely thereon, substantially as described.

In testimony whereof I affix my signature.

SIMON DOKK OLSEN.

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