Nut.
1. (
Machinery.) A piece of metal
a tapped and adapted to be screwed on the end of a butt
b.
A second nut
g, screwed down upon the first, is called a
jam-nut, check-nut, pinching-nut, or
locknut. (See nut-lock.) A
nut-lock is a device of any kind for fastening a nut; a
lock-nut is a nut or bur which fastens another nut.
B shows a shaft and sleeve with two bushes
c d, one drawn by a
drawing-nut e, the other driven by a
forcing-nut f.
C D are forms of elastic nuts.
One has an opening which permits expansion, and the other screws down upon a spiral spring.
2. (
Vehicle.) Axle-nuts are screwed on to the ends of the spindles or arms of carriage-axles, to hold the wheels on the spindles.
The exercise of ingenuity in this line has been in devices to prevent the nuts from becoming unscrewed, and thus allowing the wheels to roll off. In the ordinary method, a closely fitting nut is screwed on the threaded end of the spindle, the threads on the near side of the carriage being left-hand threads, and those on the off side, right-hand threads, so that the ordinary motion of the wheels tends to roll the nuts on, and not off.
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Bolls and nuts. |
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Axle-nuts. |
Sometimes the nut is fastened by a key of metal or leather, sometimes by a jam-nut.
In the examples,
a has a flanged cap instead of a screw-nut, and this is held by a transverse key slipped through a hole in the hub-band.
b b′ are views of an axle-nut which is secured on the axle by combining with it a spring friction-brake, which acts on the thread of the screw.
The lever or arm of the brake extends beyond one of the faces of the nut, so that the brake may be withdrawn from the thread of the screw by the act of putting on the screw-wrench, to take off or put on the nut.
In
c c′, when the nut is screwed up to its place, the lever-key is thrown into such position as to prevent the nut becoming unscrewed.
To unscrew the nut, the lever-key is turned to a horizontal position
[
1538]
by entering a small iron pin through a hole and causing it to bear upon the key while the nut is started back.
The two figures illustrate the respective positions of the lever-key.
In
d d′ the divided nut is clamped in a groove of the spindle, the shoulders of the groove being formed respectively of the enlarged, bearing portion of the spindle and of the outer boss.
One portion of the nut may be hinged to the other, and the jaws opened to enable it to be placed in its seat; or the two pieces may be locked together in any convenient manner.
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Young's axle-nut. |
In
Fig. 3347, a cap covers in the outer end of the hub, and is not removed for the purpose of taking off the wheel.
A pin is thrust in from the outside through a hole in the cap, and engages with a groove in the axle-nut, so as to lock the two together.
The wheel being then rotated in the proper direction, the cap and nut revolve, and the latter is unscrewed from the end of the spindle, releasing the wheel without soiling the fingers by handling the nut.
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Monkey-wrench. |
Many devices to prevent nuts from becoming unscrewed are found in machinery subject to jar, and particularly in railroadrail fastenings and fish-plates.
See nut-lock.
3. The screwed sleeve which operates the movable jaw of a monkeywrench.
4. One of the rollers or crushingcylinders of a cider-mill.
5. (
Nautical.) A projection on the
shank of an anchor to hold the
stock in place.
6. (
Fire-arms.) The tumbler of a gun-lock.
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Nut-cracker. |
