US915214A - Nozzle. - Google Patents

Description

. with the needle.

chamber between the nozzle and needle is uniform and symmetric for the purpose of' equal pressure distribution. This construction also applies to Fig. 1. In the nozzle 11 is the chamber14 in which the end 15 of thel needle stem 12 operates as a piston. The' opposite end of the chamber 14 1s closed by a packing 16 surrounding theneedle. Communicating with the chamber 14 is the fluid connection 17 having a valve 18. This` valve may connect the chamber 14 with a source of pressure, as from the penstock back of the gate, -or connect the chamber with the exhaust. The extension 19 of theneedle has connection with the mechanical needle control 20 which, in this instance, as a hand wheel having threaded connection The extension 19 of the needle lies opposite the concave or bentaside portion 191 of the nozzle and is directly accessible lfrom without the nrozzle walls without any disassemhlin of parts. lhe/n operated mechanically t e key 21 serves to hold the wheel 2O from longitudinal movement relative to the nozzle. Mounted on the extension 19 of the needle are the stops'22 which are adjustable; the outer one of which may be set so that the n edle may not reach full closedposition in tlie nozzle. This precaution will prevent water hammer in the event the needle should suddenly move toward closing osition. The inner adjustable stop 22 wil serve to limit the maximum opening of the nozzle and thereby prevent excessive use of ,water when but a limited maximum is available.

Besides the chamber 14 in the nozzle 11 there is the chamber 23 in which is the piston 24 also mounted on the needle. Communicating with the chamber 23 is the Vfluid connection 25 having thc valve in the chamber 27. The chamber' 27 has the controllable inlet 23 for fluid under pressure and the exhaust outlet 2). T he controllable inlet may receive the fluid under pressure from the penstock back ol' the gate. The valve 26 1s of the poised type and is controlled by a valve stem 31. rlhe fluid under pressure entering at 23 passes around the valve 26 under its llange extension and through the adjustable cataract portion 30 of the chamber 27 above the valve 26. This lluid may seep out through the opening in the ,valve 26, which opening is controlled bythe valve stem 31. Connected to the stem 31 is the link 32 mounted intermediately of the ends of the lloating lever 33. One end of the lever 33 is connected by the link 34, bell crank lever 35, and link 3 6, with the extension 19 of the needle. The opposite end of the floating lever 33 is connected to a governor 37.

inasmuch as the pistons 15 and 34 are of different effective areas, the fluid under pressure which is admitted to the chambers 14 and 23 may be derived from the A`same source. 4Such bein "the cas-e, the interposed packing 16 is not su ejected to material difierence in pressures in the regular operation of the device.

When the needle of Fig. 2 is connected up for automatic control or relay governing, the device will o crate as follows: Should the speed of the driven element become excessvalve 26 that the fluid under pressure passing the adjustable cataract 3.() is just taken care of b this seepage opening. This rise of the va ve 26 wili connect the chamber 23 through the openinfY 25 with thea exhaust outlet 29. The fluid under pressure in the chamber 14 will accordingly actuate the needle piston 15 toward closing position. This movement of the needle will be transmitted through link 36, bell crank 35 and link 34`v to move the floating' lever 33 about the governor 37 as a l`"ulcru1n.` link 32 to cause the stein 31 to move down to closethe seepage opening in the valve 26.

,This will airain cause an unbalancing of the pressures about the valve 26, for the passage of Huid about the adjustable cataract 30 to the upper side of the valve 26 will, on this greater area, cause the pressure to force the valve 26 downward to again give the seepage opening proper area for outlet.. This movement of .the valve downward closes the fluid connection 25 and thereby holds the needle in the position to which 1t was forced. Should the speed of the driven element fall below the normal,` th n the lloating lever 33 will move downward about thelink 34 as a fulcrum, and through the link and stem 31 close the seepage opening in the valve 26, causing the valve 26 to recede to create proper area of seepage opening to take care of the-fluid under 'pressure passing cataract 30. This movement of the valve 26 downward will permit fluid under pressure entering at opening 23 to pass through luid connections 25 to force the pistonv 24 against the resistance of fluid in the chamber 14 and thereby retract the needle. This movement of the needle causes a secondary movement of the valve 26 through the linkages 36, 35, 34,'and lever 33 about the governor 37 as a fulcrum.l These control devices are such that any one or all may be disconnected. Normally, Huid under pressure is always in the lchamber 14 and the needle is accordingly held toward nozzle closing position.

Notwithstanding the governor is connect- This will cause .the

-jected to the stress of f zle and having the outer portion located adjacent the concave side ol the curved portion tieni/i ed to the device, the' needle may be een trolledby hand by bringing the Wheel 20 into position for locking by the leyQ, then rotatlng the wheel as desired.

The two 'forms of apparatus disclosed bye the drawings accompanying this spec-incaton show that the nozzle is so arranged that the` water is directed against the opposite and opposing sides of the valve, whereby the valve is freed from-side thrusts and in consequence a much stiffer needle or valve can be used, this change in construction assisting in overcoming the defects of the prior types an aperture, of

of these needles, and by substantially irn- Inersing the entire needle or valve'in the water, the material composing the same is subcompression, thereby further reducing the liability for said material to experience vibrations.

What is claimed and it is desired to secure byLetters Patent, is:-

1. The combination with a curved-passage nozzle having. an aperture, of a needle eX- tended through thecurved walls of said nozof the' nozzle. and directly accessible from Without the nozzle walls and adapted to control the thoroughfare through said apertureVy the'space between the portion ol' the needle Within the nozzle and the opposite walls ol' the nozzle-beine' symmetrically enveloped about said needle portion.

2. The eornbinution with a curved-passage nozzle havinkgr an aperture, ol` a needle extended through the curved walls ol said nozzle and adapted to control the thormlghl'are eil through said aperture, the nozzle having its Wall extending inwardly and closely adja cent tlievneedle from the place Where the needle extends through the nozzle wells, Where- J the Space between the portion ,of the need e Within the nozzle and the opposite Walls of the nozzle is symmetric about said portion of the needle.

3. The combination with a nozzle having a needle extended through the walls of seid nozzle to control the thoroughfare .through said aperture, the outer portion of the needle being directly accessible lrorn without the nozzle Wellsw the space between the portion er" the needle wit 'n the 'nozzle and the opposite Wallsof the nozzle being -nnietrically enveloped about Said portion o1" the needle and said needle portion eing oi' decreasing cross-'sections toward the needle point at any p ace where these sections differ in size.

4. The combination with a nozzle having e portion curved or bent aside to receive a needle valve, of a needle valve extended through the curved Walls ol' the nozzle, the nozzle and valve being constructed and nrranged to cause the space between the portion or" the needle valve within the nozzle and the surrounding Walls of the nozzle to be symmetrically enveloped about said needleportion. ln testimony whe-.reel affix my signature in presence of two witnesses.

ARNOLD PFA/lll,

roceed ing Witnesses:

Grao. il). KIRK, G. F* DE yl/E1n.

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