Steer′ing-appa-ra′tus.
A device in aid of the steersman, being interposed between the tiller or tiller-wheel and the rudder-head.
See also steer-ing-wheel.
In
Sickel's steam-steering apparatus (
Fig. 5757), in use since 1860, the steering-wheel
a and the barrel
c for the steering-chains are upon separate shafts, in a line with each other.
On the shaft
b of the steeringbarrel is a toothed wheel, gearing with a pinion upon a crank-shaft, which is driven by a small steam-engine having two cylinders working at a right angle to each other.
The eccentrics which work the slidevalves of that engine are upon a separate shaft, having a pinion driven by a spur-wheel fixed to and driven by the steering-wheel.
Thus when the steeringwheel is turned, it causes the eccentricshaft to turn, and every revolution of the eccentric-shaft causes the engine to make one revolution, and thus the motions of the barrel are made to correspond exactly with those of the steering-wheel.
Another steering-wheel
d is made fast to the barrel, to be used in the ordinary way, in the event of the engine getting out order; in which case the wheels and pinions are thrown out of gearing.
Fig 5758 is North's steering-apparatus, 1865.
Attached to the upright shaft that carries the bevel-gear
a is a cam
b having two grooves on its periphery for the reception of the chains.
This cam has a spline that allows it to traverse longitudinally on the upright shaft.
The gear-wheel and cam are rotated by means of the pinion on the horizontal shaft that carries the steering-wheel.
The machinery is mounted on a frame, bolted to the deck of the vessel.
On the rudder-post is secured a quadrant
d, so depressed in its periphery to correspond with the eccentric action of the cam
c in its rotation as always to present the same face to its action.
The periphery of the segment has two grooves for the reception of the chain.
When the rudder is “hard up” the quadrant presents its longest radius to the shortest radius of the cam, thereby increasing the power upon the rudder at the time when it is most required.
In
Fig. 5759, the tiller-wheel shaft has a right and left handed screw which passes through nuts which are connected by arms to the gudgeons of the rudder-head.
The rotation of the shaft draws the nuts simultaneously toward or from the rudder, and rotates the latter on its axis.
Hunt's steering and propelling apparatus (English patent) combines the two operations in one, the axis of the screw being made to oscillate in a horizontal plane by means of the tiller, while the rotation of the axis by the engine is not affected.
a is a driving-shaft rotated by the steam-engine;
b, a bearer;
c e d m n, the gearing and shafting connecting the shaft
a with the short shaft
i of the propeller.
The shaft
d is carried down to the step
z projecting from the stern-post, and is inclosed by a case
f which has independent motions thereon by means of
[
2372]
the tiller
w. The trunk
g is formed by an enlargement of the case
f, and incloses the lower pair of bevel gears
m and
n, and the short shaft
i, to whose end the propeller
p p′ is attached by a coupling
o. This arrangement is used in the propulsion.
The steering part of the apparatus consists of a tiller-wheel
w, shaft
q, bearing
r, and bevel-wheel
t gearing into a similar bevel-wheel (see the other figure) on the end of a short screwshaft
v which takes into a quadrant
x attached to the top of the case
j above the plate on which the vertical plate
q is stepped When the steersman turns the wheel
w, motion is communicated to the quadrant
x and the case
f, thereby rotating the propeller-shaft
i o in a horizontal plane, and thereby varying the angle of presentation of the axis of the propeller to port or starboard, as the case may be, giving a positive lateral propulsion to the stern of the vessel.
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North's steering apparatus. |
Blackie's electric signal for steering-apparatus is to enable the pilot of a vessel to communicate with the engineer or helmsman.
When the pilot sends an order he presses a knob, and a bell rings, meaning attention.
The engineer looks to the index, which resembles a clock face, on which are printed the 5 general orders used, namely,
stop: ahead easy; ahead full speed; back easy; back full speed. The pointer indicates the order, and always remains at the last, and is locked The device by which the pilot transmits his orders to the engineer is constructed as follows: First, there is a dial on which the five orders described are printed.
A pointer, like the hand of a clock, moves at the will of the pilot from order to order.
The pointer is attached to a cylinder of iron 4 1/2 inches long, 1/2 inch diameter, which leads from the center of the dial backward at right angles, and is supported at each end eccentrically.
On each side are two electro-magnets and one underneath; there being one magnet for each order.
A wire from each magnet leads to the pilot-house, and all wires are connected with a battery.
By means of five knobs in the pilot-house the connections are made; one on each wire The iron cylinder, or keeper, moves from side to side, or downward, according to the attraction of the magnet; and as the pointer is attached to the keeper or cylinder, the movements on the dial will correspond with movements of the keeper, by reason of its eccentric motions.
By a double arrangement of wires in connection with a galvanometer, the rudder is made to indicate its position on a dial for the observation of the captain and pilot.
