US1692296A - Safety valve - Google Patents

Safety valve Download PDF

Info

Publication number
US1692296A
US1692296A US222667A US22266727A US1692296A US 1692296 A US1692296 A US 1692296A US 222667 A US222667 A US 222667A US 22266727 A US22266727 A US 22266727A US 1692296 A US1692296 A US 1692296A
Authority
US
United States
Prior art keywords
valve
bushing
stem
casing
boiler
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US222667A
Inventor
French E Godsey
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US222667A priority Critical patent/US1692296A/en
Application granted granted Critical
Publication of US1692296A publication Critical patent/US1692296A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K17/00Safety valves; Equalising valves, e.g. pressure relief valves
    • F16K17/02Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side
    • F16K17/04Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded
    • F16K17/10Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded with auxiliary valve for fluid operation of the main valve
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/1624Destructible or deformable element controlled
    • Y10T137/1632Destructible element
    • Y10T137/1789Having pressure responsive valve

Definitions

  • Thisk invention relates to 4safety valves of the kind that are usually mounted in boiler connections and the'like to prevent the escape' of steam or hot water in case the connections are broken.
  • the locomotive boiler is provided with a variety ci connections leading to gages, blow-oils, etc., ⁇ and incase breakingv of these connections occurs, through wrecking of the locomotive or otherwise, the escaping steam or hotA water from theboiler will be liable to scaldthe trainmen unless means are provided to prevent Vsuch escape of the steam and hot water.
  • the primary object of the presentr inven-V tion is to provide a safety valve for such connections that willbeautomatically closed by the fluid pressure of the boilerin case such connectionsare thus accidentally broken off.
  • FIG. 1 is a perspective view of a valve ern-
  • Fig. 2 is a longitudinaly section thereof, the parts being shown in elevation; v
  • Fig. 3 is aperspective view of thevalvecarrying bushing
  • 1 is a casing provided o n its interior -end ,with screw-threads 2', whereby it vmay be screw-threaded into a boiler and on the exterior end with lefthand screw- ⁇ threads 3, to the end that the valvebonnet 4 may be screwed thereto.
  • This casing 1 hasl va centralfport or openingv leading into the boiler, which port is surroundedby an annularrshoulder 6'.
  • a bushing' 7 is screw-threaded as at 8, such screw-t ireads being formed at the inner end of the bushing and if desired throughout the length 'of thev bushing, as shown.
  • the inner end of the bushing is provided with a' valve lchamber 9 which, near its inner end, has a valve seatvlO, and a valve 11 having a stem portion 12 is mounted in the valveA chamber 9 so that the valve 11 can play between the shoulder 6 and the valve seaty l0.
  • the size of the valve 11 issuch that, when it is slightly raised off or itsV seat and out of around the valve and gain access to a groove 13,v Fig. 3, exterior to the valve 11 and formed about the ystem '121A plurality of'ispiral g grooves 14 extend from the groove 13 around the stem 12 to the outer end thereof.
  • TheH serted the valve chamber 9 ot the bushing,
  • PaiEnripol striv/ff len v contacta/'ith theshouldei 6,'steamV may passL ing 7 at its exterior end 7 lits snugly withinV an interior chamber of the bonnet 4.
  • the valve-operating stem 22 is screw-threaded at 22 into the eXterior end of the bonnet'4' and is provided with the usual or any suitat its interior end, an extension 24 of .smallerv diameter than the main valve-operating stem 22 and of considerably less diameter than the interior oi the bushing 7 'at that point, to the end that the stem that passes around the valve ll ⁇ from the boiler may pass around the valve extension 24.
  • this ei:-v tension 24 is screw-threaded to the interior end of the valve-operating stem, of which it forms a part, and for the purpose oi' enabling the same to be screwed into or unscrewediirom said stein, he same is provided with ilattened faces ⁇ 24, as clearly shown in Fig. 4.
  • said stem is provided with a valve 25, here shown as preferably formed by the suitably shaped end of said valve-operating stem and seats on a valve seat 26, and when seated prevents the outward passage of steam.
  • valve-operating stem 22 is slightly reduced at 2T, so that there is an annular space surrounding the stem opposite an opening 28 leading into the interior of the bushing.
  • a pipe 29 is secured into or otherwise connected to the casing l, and when the parts are assembled, the port or opening 28 is opposite the open end of the pipe 29, which pipe leads to the gage cock or other Connection.
  • the opening 28 is larger than that of the end opening of the pipe 29p, in order to insure perfect registration without the necessity ot exercising undue care in that regard when the parts are assembled.
  • rlhe casing l is formed tor the reception of a wrench to screw the Vsame into a boiler, and the bonnet4 is likewise formed for the reception of a wrench for the purpose of screwing the same onto the casing.
  • openings 7 are provided in the outer end ot' the bushing, through which a rod may be passed for this purpose.
  • groove 30, Figs. l and 2 is formed around the casing opposite the point where the part 24 of the valve-operating stem bears upon the valve stem 12, and immediately opposite this groove 30 in the' casingis formed an annular groove 3l around the bushing.
  • the casing is Yscrew-threaded into the boiler in the absence ing, the threads uniting the two parts being such that when the bushing is screwed home so that the inner end oi the bushing contacts with the shoulder 6, the port 28 comesoppo4 siteithe opening oi? the pipe 29.
  • the bonnet 4 is Vthen screwed onto the exterior end of the bushing, the valve op era'ting'stem 22 tlrst having ⁇ preferably been screw-threaded in to the outer end of the bonnet.
  • the packing 34 surrounds the valve-operating stem 22 and'is compressed between oppositely disposed annular concave shoulders in the bonnet 4 and onthe end of the bushing, 1 i j VJ ith the parts thus assembled, the valveoperating stem 22 is screwed down through the operation of the handle 23 with the stern extension 24 resting in the concave socket 17 of the valve stem, until the valve 11 is slightly raised from its seat l0.
  • This valve seat 26 is one that requires frequent grinding to cause it to V'tunetion perfectly, and by unscrewing the bonnet 4 romthe casing 1,'said bonnet with the valve-operating stem”and the valve 26, as well as the valve stem extension 24, are readily removed and the valve seat 26 exposed for grinding without removal o'l' the parts from their connection with the boiler. lnas ⁇ much as the pressure on the valve stem l2 has'been withdrawn by reason ot the withdrawal of thevalve-operating stem 22, steam passing outwardly through the port 5 forces the valve 11" lirmly on its seat l0, and thus the escape oi steam is prevented and the grinding operation can be effected even though steam is carried in the boiler.
  • valve unit is made of VMonel metal, though this is not absolutely essential.
  • valve constituting this invention is one ot extremely simple construction, readily assembled and disassembled with few operations, and requiring no tools other than a wrench, and a rod to pass through the openings Z in the bushing.
  • a valve of the Acharacter described the combination of the casing open at inner end, a tubular bushing sicured in the casing, a valve and valveseat .located in the inner end of the bushing, a bonnet secured to the outer end ot the casing, a valveoper ating stem screw-threaded into the bonnet and passing into the bushing and into operative relation with the valve in the inner end of the bushing, and a valve on said valve stem and seating on a valve-seat within said bushing.
  • valve ot the combination of the casing open inner end, al tubular bushing having two valve-seats :formed therein, separate valves cooperating one with each seat, a bonnet screw-threaded 0n said casing, and a valvestem screw-threaded in said bonnet for openling the inner valve and closing the outer valve when the inner valve is fully open, thek inner valve adapted to be moved toward its seat by fluid pressure on retraction of the valve stem and outer valve.
  • a valve et the character described the combination of a casing adapted to open int-o aboiler, and a ⁇ steam connection lead# ing from saidcasing, a tubular bushing in said casing having aV port leading to said steam connection, a valve within the inner end or said biiishing capable of being closed by Vpressure trom the boiler, a lvalve-operating stem to open said valve against boiler pressure, and a valve on said va-lvefoperating stem between the boiler and said steam con# nection.
  • a valve of the character described the combination or" a casing and aibushing, a valve in said bushing closingl under boiler pressure, said casing'and bushing being pror vided withfracture lines exterior to said
  • a casing adapted to openI a steam conveying yenduit leading therefrom, a bushing secured tits ner end in said casing and removable 'through the outer endV thereof, safety valve mounted in the inner ol said bushing, a bonnet secured to the casino' and, withy i the casing, enclosing said bushing, and a y valve-operating stem adjustably mounted.
  • bonnet and stem may beremoved without disturbing said casing or conduit.
  • the combination oit' casing open at its inner end, a bushing in said casing having a valve-receiving chamber with an inwardly projecting lug, and a revoluble valve in .said chamber, saidvvalve being provided with a peripheral recess capable of being brought into registry with said lug.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Lift Valve (AREA)

Description

Patented Nov. 20, 1928.
" UNITED si'iAfTEfs .FRENCH n. 'Gomma or BLUiirrEL-n, WEST VIR-orma;
SAFETY VALVE. 'Y
Application filed September 28, 1927." Serial'No. 222,667. y
Thisk invention relates to 4safety valves of the kind that are usually mounted in boiler connections and the'like to prevent the escape' of steam or hot water in case the connections are broken.
The locomotive boiler is provided with a variety ci connections leading to gages, blow-oils, etc.,` and incase breakingv of these connections occurs, through wrecking of the locomotive or otherwise, the escaping steam or hotA water from theboiler will be liable to scaldthe trainmen unless means are provided to prevent Vsuch escape of the steam and hot water. V
The primary object of the presentr inven-V tion is to provide a safety valve for such connections that willbeautomatically closed by the fluid pressure of the boilerin case such connectionsare thus accidentally broken off.'
and which may be assembled or dissembled with a minimum amount of work. y
The inventive idea iscapable of receiving a variety of expressions, one of which, for the purpose of illustrating the invention, is shown inl the accompanying drawings, but it is to be expiesslylunderstood that` such drawings are for the purpose of illustration only and are not designed to deline the limits ot the invention, reference being had' to the appended claims for lthis purpose.
e In said drawings-- Fig. 1 is a perspective view ofa valve ern-,
bodying the invention;
Fig. 2 is a longitudinaly section thereof, the parts being shown in elevation; v
Fig. 3 is aperspective view of thevalvecarrying bushing; and
Fig. 4 stem.
numerals designate like parts throughout is a brokenA detail of the valve" In said drawings, in which like reference the several views," 1 is a casing provided o n its interior -end ,with screw-threads 2', whereby it vmay be screw-threaded into a boiler and on the exterior end with lefthand screw-` threads 3, to the end that the valvebonnet 4 may be screwed thereto. This casing 1 hasl va centralfport or openingv leading into the boiler, which port is surroundedby an annularrshoulder 6'. Within the casing 1, a bushing' 7 is screw-threaded as at 8, such screw-t ireads being formed at the inner end of the bushing and if desired throughout the length 'of thev bushing, as shown.
vThe inner end of the bushing is provided with a' valve lchamber 9 which, near its inner end, has a valve seatvlO, and a valve 11 having a stem portion 12 is mounted in the valveA chamber 9 so that the valve 11 can play between the shoulder 6 and the valve seaty l0.
The size of the valve 11 issuch that, when it is slightly raised off or itsV seat and out of around the valve and gain access to a groove 13,v Fig. 3, exterior to the valve 11 and formed about the ystem '121A plurality of'ispiral g grooves 14 extend from the groove 13 around the stem 12 to the outer end thereof. TheH serted the valve chamber 9 ot the bushing,
which chamber' has an inwardly 'projecting lug I9, Fig. 8, `while the valve is 'provided with a corresponding groove 20. When the valve Vis'. inserted'within the bushing, thev groove 2O` is brought oppositethe lug 19 tothe end that the valve may readily pass into they bushing and then given a slight turn, whereupon the lug 19 preventsthe valve from dropping out, the valve and its stem 'nevertheless being left free to vrotate' within the valve chamber in theA` bushing.; Byv reasonv of the spiral grooves 14. on the stem ofthevalve and the, grooves 15 andI 16 on the face ofthe valve, steam passing outwardly from the boiler serves to rotate theyalve, thus keeping the valve and valve receiving chamber tree from, any accumulation of scale or dirt. The bush.
PaiEnripolierten/ff len v contacta/'ith theshouldei 6,'steamV may passL ing 7 at its exterior end 7 lits snugly withinV an interior chamber of the bonnet 4. The valve-operating stem 22 is screw-threaded at 22 into the eXterior end of the bonnet'4' and is provided with the usual or any suitat its interior end, an extension 24 of .smallerv diameter than the main valve-operating stem 22 and of considerably less diameter than the interior oi the bushing 7 'at that point, to the end that the stem that passes around the valve ll `from the boiler may pass around the valve extension 24. Preferably this ei:-v tension 24 is screw-threaded to the interior end of the valve-operating stem, of which it forms a part, and for the purpose oi' enabling the same to be screwed into or unscrewediirom said stein, he same is provided with ilattened faces`24, as clearly shown in Fig. 4. At the point where the valve-operating stem unites with extension24, said stem is provided with a valve 25, here shown as preferably formed by the suitably shaped end of said valve-operating stem and seats on a valve seat 26, and when seated prevents the outward passage of steam.
The valve-operating stem 22 is slightly reduced at 2T, so that there is an annular space surrounding the stem opposite an opening 28 leading into the interior of the bushing. A pipe 29 is secured into or otherwise connected to the casing l, and when the parts are assembled, the port or opening 28 is opposite the open end of the pipe 29, which pipe leads to the gage cock or other Connection.
Preferably the opening 28 is larger than that of the end opening of the pipe 29p, in order to insure perfect registration without the necessity ot exercising undue care in that regard when the parts are assembled.
rlhe casing l is formed tor the reception of a wrench to screw the Vsame into a boiler, and the bonnet4 is likewise formed for the reception of a wrench for the purpose of screwing the same onto the casing.
For the purpose of enabling the bushing 7 to be screw-threaded into the casing l, openings 7 are provided in the outer end ot' the bushing, through which a rod may be passed for this purpose. groove 30, Figs. l and 2, is formed around the casing opposite the point where the part 24 of the valve-operating stem bears upon the valve stem 12, and immediately opposite this groove 30 in the' casingis formed an annular groove 3l around the bushing. These two grooves serve to weaken the casing and theV bushing at this point, and in casev the structure becomes broken at any place the break will occur at this weakened point, in which case the steam from the boiler passing outward through the porty 5 forces the valve ll onto the valve seat l0,
An external annular thus effectively preventing the escape of steam or water from the boiler. h
Vln assembling the parts, the casing is Yscrew-threaded into the boiler in the absence ing, the threads uniting the two parts being such that when the bushing is screwed home so that the inner end oi the bushing contacts with the shoulder 6, the port 28 comesoppo4 siteithe opening oi? the pipe 29.
The bonnet 4 is Vthen screwed onto the exterior end of the bushing, the valve op era'ting'stem 22 tlrst having` preferably been screw-threaded in to the outer end of the bonnet. The packing 34 surrounds the valve-operating stem 22 and'is compressed between oppositely disposed annular concave shoulders in the bonnet 4 and onthe end of the bushing, 1 i j VJ ith the parts thus assembled, the valveoperating stem 22 is screwed down through the operation of the handle 23 with the stern extension 24 resting in the concave socket 17 of the valve stem, until the valve 11 is slightly raised from its seat l0. Y y
llith the parts in this position steam passes through the port 5 around the valve 1l 'through the groove 14' and around the valve stem extension 24, and, the valve 25 being slightly raised from its seaty26, passes through the port 28and into the pipe By screwing the valve stem 22 in to a sutlicient extent, the valve 25 may seat lirmly on 'the seat 26, thus entirely preventing the es- AD cape or" steam through the ports 28 and the pipe 29. This valve seat 26 is one that requires frequent grinding to cause it to V'tunetion perfectly, and by unscrewing the bonnet 4 romthe casing 1,'said bonnet with the valve-operating stem"and the valve 26, as well as the valve stem extension 24, are readily removed and the valve seat 26 exposed for grinding without removal o'l' the parts from their connection with the boiler. lnas` much as the pressure on the valve stem l2 has'been withdrawn by reason ot the withdrawal of thevalve-operating stem 22, steam passing outwardly through the port 5 forces the valve 11" lirmly on its seat l0, and thus the escape oi steam is prevented and the grinding operation can be effected even though steam is carried in the boiler. Moreover, under the requirements of the Interstate Commerce Commission, the interior passages of these valves have to be inspected and cleaned at short intervals, and by thus removing the bonnet and the valve-operating stem, as just described, the interior passage of the bushing down tothe valve stem i2 is open Vfor cleaning by the passage of a 'rod therethrough.` In case there is no steam in with a suitable brush or rod without discon-v nectingthevalve casing from the boiler, Preferably the valve unit is made of VMonel metal, though this is not absolutely essential.
It will beobserved that the valve constituting this invention is one ot extremely simple construction, readily assembled and disassembled with few operations, and requiring no tools other than a wrench, and a rod to pass through the openings Z in the bushing.
lVhile the valve shown in the drawings'has been specifically described in detail, it is to be understood that the invention is not limited to such specific details and that the same may be varied within the limits ot the appended claimsv without departing from the invention. l
lVhat is claimed is: y
vl. In a valve of the Acharacter described, the combination of the casing open at inner end, a tubular bushing sicured in the casing, a valve and valveseat .located in the inner end of the bushing, a bonnet secured to the outer end ot the casing, a valveoper ating stem screw-threaded into the bonnet and passing into the bushing and into operative relation with the valve in the inner end of the bushing, and a valve on said valve stem and seating on a valve-seat within said bushing.
2. In a valve ot the character described, the combination of the casing open inner end, al tubular bushing having two valve-seats :formed therein, separate valves cooperating one with each seat, a bonnet screw-threaded 0n said casing, and a valvestem screw-threaded in said bonnet for openling the inner valve and closing the outer valve when the inner valve is fully open, thek inner valve adapted to be moved toward its seat by fluid pressure on retraction of the valve stem and outer valve.
3. In a valve of the character described, the combination of a casing having a port for communicatingwith a boiler, a bonnet valve.
`into a boiler, and having secured to-theouter end of the casing, a tubular bushing within the easing, a valve and valve-stem mounted in the inner end of said bushing, a valve-operating stem extending through.v said bonnet into thebushing and into operative relation with said valve-stem, said bushing and casing being weakened atv Va point approximately opposite the outer end ot said valve-stein.
In a valve et the character described, the combination of a casing adapted to open int-o aboiler, and a `steam connection lead# ing from saidcasing, a tubular bushing in said casing having aV port leading to said steam connection, a valve within the inner end or said biiishing capable of being closed by Vpressure trom the boiler, a lvalve-operating stem to open said valve against boiler pressure, and a valve on said va-lvefoperating stem between the boiler and said steam con# nection. 'i
5. In a valve of the character described, the combination or" a casing and aibushing, a valve in said bushing closingl under boiler pressure, said casing'and bushing being pror vided withfracture lines exterior to said Ina valve of the character described, the combination of a casing adapted to openI a steam conveying yenduit leading therefrom, a bushing secured tits ner end in said casing and removable 'through the outer endV thereof, safety valve mounted in the inner ol said bushing, a bonnet secured to the casino' and, withy i the casing, enclosing said bushing, and a y valve-operating stem adjustably mounted. in
said bonnet7 whereby said valve, bushing,
bonnet and stem may beremoved without disturbing said casing or conduit. i 7. In a valve of the character described, the combination oit' casing open at its inner end, a bushing in said casing having a valve-receiving chamber with an inwardly projecting lug, and a revoluble valve in .said chamber, saidvvalve being provided with a peripheral recess capable of being brought into registry with said lug.
In testimony whereof I have siened this specication.
i rennen n eonsnr.
US222667A 1927-09-28 1927-09-28 Safety valve Expired - Lifetime US1692296A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US222667A US1692296A (en) 1927-09-28 1927-09-28 Safety valve

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US222667A US1692296A (en) 1927-09-28 1927-09-28 Safety valve

Publications (1)

Publication Number Publication Date
US1692296A true US1692296A (en) 1928-11-20

Family

ID=22833190

Family Applications (1)

Application Number Title Priority Date Filing Date
US222667A Expired - Lifetime US1692296A (en) 1927-09-28 1927-09-28 Safety valve

Country Status (1)

Country Link
US (1) US1692296A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2678799A (en) * 1948-01-02 1954-05-18 Phillips Petroleum Co Quick closing valve
US2800140A (en) * 1952-12-15 1957-07-23 James C Ross Faucet
US3035595A (en) * 1958-10-30 1962-05-22 Phillips Petroleum Co Fluid handling structure
US20060219296A1 (en) * 2005-04-05 2006-10-05 Hui-Ming Lin Safety machanism of a high-pressure gas outflow control for cutting off gas outflow when the control is broken

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2678799A (en) * 1948-01-02 1954-05-18 Phillips Petroleum Co Quick closing valve
US2800140A (en) * 1952-12-15 1957-07-23 James C Ross Faucet
US3035595A (en) * 1958-10-30 1962-05-22 Phillips Petroleum Co Fluid handling structure
US20060219296A1 (en) * 2005-04-05 2006-10-05 Hui-Ming Lin Safety machanism of a high-pressure gas outflow control for cutting off gas outflow when the control is broken

Similar Documents

Publication Publication Date Title
US1692296A (en) Safety valve
US645696A (en) Blow-off valve.
US709262A (en) One-way valve.
US483635A (en) Check-valve
US2160657A (en) Valve for control of mediums under pressure
US854108A (en) Combined gage and stop cock.
US1160285A (en) Blow-off cock.
US1078420A (en) Water-gage cock.
US1188535A (en) Boiler feed-admission valve.
US708527A (en) Combined gage-cock and safety-valve.
US829632A (en) Gage-cock.
US1072245A (en) Combination check and stop valve.
US1388624A (en) Safety scaleproof automatic gage-cock
US665209A (en) Water-gage.
US780414A (en) Safety-valve.
US465766A (en) roberts
US1654451A (en) Steam valve or gauge cock
US564095A (en) Water-gage
US529133A (en) Blow-off cock
US1013426A (en) Blow-off valve.
US307294A (en) Gage-cock
US838055A (en) Safety-valve for water-gages.
US1066891A (en) Convertible blow-off cock and check-valve.
US754963A (en) Water-gage.
US618696A (en) Gage-cock