US2498045A

US2498045A - Deceleration apparatus

Info

Publication number: US2498045A
Application number: US690768A
Authority: US
Inventors: Charles T G Looney; Lynn G Howell; Bruce G Johnston
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-08-15
Filing date: 1946-08-15
Publication date: 1950-02-21
Anticipated expiration: 1967-02-21

Description

@l Thm C. T. G. LOONEY ETAI- DECELERATION APPARATUS F'iled Aug. 15, 1946 INVENToRs CHARLES I G. LOONEY L LY/VN 6. HOWELL www Feb. 21, 195o JOHNS TON BRUCE' ATTORNEY Patented Feb. 217 1950 leans DECELERATION APPARATUS Charles T. G. Looney, Silver Spring, Md., Lynn G. Howell, Houston, Tex., and Bruce G. Johnston, Bethlehem, Pa., assignors to the United States of America as represented by the Secretary of the Navy Application August 15, 1946, Serial No. 690,7.68

(Cl. J3-167) 11 Claims. l

This invention relates generally to deceleration apparatus and is particularly directed to improvenents in apparatus for the deceleration of projec iles.

Ruggedness tests of vacuum tubes and other components constituting the proximity fuze are presently made by the vertical method, whereby the materials being tested are contained in a projectile and red directly upwardly and permitted to fall base downwardly in a field within the vicinity of the gun where the projectile is recovered by digging it out of its embedded location. This method requires a large plot of ground in a secluded area far from inhabited areas due to the frequent occurrence of wild or improperly iired projectiles. A large group of men are required to operate the gun, observe the landing of each projectile, and dig the projectile out of the ground; all of which duties are performed by the men under the dangerous condition of being struck by a falling projectile. A great deal of time is consumed since the materials 7being tested have to be shipped to and from the laboratory and the testing grounds. Also, damage to the materials within the projectile may occur on landing, which situation gives rise to the necessity of repeated tests in order to arrive at an accurate conclusion since it would not be known if any of the damage was caused on iiring the projectile.

The present invention provides an improved ruggedness test apparatus wherein the projectile containing the materials being tested is tired horizontally and decelerated after a relatively short distance or travel by a iiuid under pressure. The

'apparatus is suiciently compact to be housed in a small space within the vicinity of the laboratory or factory. The test itself is positive in result Without requiring unnecessary duplication of effort and does not subject the operators, who are few in number, to any dangers that are prevalent in the vertical recovery method.

The principal object of the present invention is to provide aprojectile deceleration apparatus which is compact and simple in construction and eicient in operation.

Another object of the present invention is to provide apparatus for decelerating projectiles which may be operated by very few men without subjecting the operators to any of the dangers that are prevalent in the present testing methods.

A further object of the present invention is to provide apparatus that permits a greater rapidity of ruggedness tests.

A still further object resides inthe provision of a projectile decelerating apparatus which employs fluid under pressure for retarding the iired projectiles within a short distance from the point of re.

These and other objects of the invention will be evident from the following specification and the accompanying drawings, in which:

Figure 1 is a diagrammatic view partly in sectionv of the projectile decelerating apparatus.

Figure 2 is a side sectional view in elevation of the gate apparatus. I

Figure 3 is a sectional view in elevation of the pressure operated switch.

Referring now to the drawings the numeral l 0- indicates a fragment of the muzzle end of the barrel of a gun whose axis is in direct alignment with that oi a deceleration pipe l2 which is of substantial length and mounted parallel to the ground of a desired height there above by suitf able standards (not shown). The gun barrel I!) and the deceleration pipe I2 may be aligned by means of a transit or by any other of the wellknown methods, but once aligned only occasional checking of alignment is necessary. The barrel l0 is spaced from the pipe I2 to provide a gap permitting the muzzle gases to escape to the atmosphere, the gap increasing in size as the gun rei coils. The muzzle end of the barrel l0 is clamped to its mounting (not shown) by a steel collar lila' which holds the gun barrel lil in alignment but permits the barrel to recoil upon ring. Like- Wise, a plurality of clamps (not shown) retain the deceleration pipe l2 in position.

A horizontally hinged gate ll shown in detail by Figure 2 is mounted in the gap between the barrel l0 and the pipe l2. Thefpurpose of the gate Il is to block off the passageway at the gap after the projectile has been fired so that the muzzle of the barrel l0 will not be injured by a Aprojectile that may be blown backward by pressure in the pipe l2, as is hereinafter described in detail.

The gate Il consists of a, base` plate member 40 l tension arm 4l to normally rest on the end of the gun barrel l0. A guide rack consists of two parallel bars t9 between and along which the A gate member 43' is swingably mountedl with the gate member 43 in its upper position the? ring circuit is closed while with the Agate mem,- ber 43 in its lowered position the ri'ng circuit is opened. The switch 52 is connected .bywires 32a; 32h in series with a ring circuitfhereinafterfdescribed in detail.

When the gun is red, its'recoilwhile increasing the gap will permit the bolt 48 to slip past the end of the barrel I andzswing `doiavnwardlyV causing the gate member 43 to fall to its lower position thus blocking off the open end'of the pipe I2. In the event the projectile, which has beer-1f fdecelerated' in the pipe I2; iis :blownicback through: the pipe I2 Eby the. iiuid pressure there:- in, the' gate member-.43 Twill varrest the movement of the projectile at the gap and prevent injury to the gun-'barrel IBB When .thelrgun. recovers from# its recoil,v andi-returns to the: positionfshown in Fig. l, the gatef43 lstilljwillbe infront-.of 'its muzzle, shieldingit -fronrthc-z.` projectile'f-.that mightbe returning-:fromtthe piper I21i iIt willbe seen that ther-extension'arm41 at this times-will be well below the bottom ofthe'guzr barreland will f'nottbe struck` byy said r-barrel eafter: recoil. Before the next firing, thearm 41 fand'assocated parts are readjusted manually.

A relatively large acylindricalx.projectileN receiV- ing.' chamber -I 3 'is provided: :with a reducediinlet pipey I 4-1which is` secured.C to andon: the sameiaxis with'A thai/rearward Iend Vof i theiideceleratingipipe I2 by a Tcouplin'gflli.; Thechamber .Imayiconztain` a cushioning material .(not fsh'ownrfsuch; fas cotton and i the liker :for stoppmg-fthe :projectile without injury to vthe equipmentxinz thoserin-- stances.' when the: fluid pressure'sin .therfpipe I 2 fails to completely'deceleratecthelprojectile;1

An air .storage tank-zlconnected; to anair compressor .(not shown) vof.fccnventional design has :a valve chamber I'I:inzzwhichaatvalvex-IB -is mounted: A pipe 'Iaconnects theavalvechamber I I lto 'thefT-f-'c'ouplingzl tio'permit:airzunder presnsure-:in thestorage tankrI 6= to now; into. the deceleratingpipe I 2` when :'thevalve ii Sisiopened: z The valve'y I8 is operatecl:by anzauxiliaryvalvefmechanism which includes :ai cylinderlfZI anda `pis-.- tonf 22S' slidably f mounted therein carrying the valve I 8 *at .one end.I and aicontact :stems-23 .at the other)endrthereof. The contactszstenr 2'3 carries at its:outerzendiancontact sleeve-128 afndyan insulatingsleeve r 29..r A contact ia1mre30=.isumounted for en gagement f with t either `v-.theI contactaasleeve 28"orthe'- insulating sleevefn29 Idepen'dingon wheth'e'rethe valve I 821s openedf or closed respectively.

Air` for shiftingy the pistonI 22in the fcylin'cler. 2I is supplied from the ftank- 'IIfthroughza/ `pipeil `underi pressure f into one side 'of fthe. cylinderfZI and discharge 0f air out4` of thefother side causing 'energizedthe Valve 25 4`is shifted to* itsfsecond 'position'and thefowf' of air:y is reversed-causingfthe piston to shift in an opposite direction. A starting switch 21a is connected between the solenoid 26 and the current source Z1 to control the operation of the valve mechanism 20.

An electrical delay apparatus 3 I, which is wellknown vin theta-ruinas a'pair 'oiinputor control terminals v32, one of whichis grounded at the cylinder 2| while the other is connected to the contact arm 30. A pair of electric conductors 32a .connectsthe output of the electric delay apparatus 3l with the gun control apparatus (not shown) isuchzas-ring. solenoid, having the switch 52 connectedlin'series with one of the electric conductors 32a sothat the firing circuit is closed `only when'thegate member 43 is in upper or non-obstructing position.

.f-.pressure operated switch 33 is mounted on the deceleration pipe I2 at its receiving and adjacent the gap between the pipe I2 and the gun barrel I0. As shown in detail by Figure 3, the switch-'i33'fconsists vof a .mounting =34 :made of a noni-conducting,- material suchi .f as .f a synthetic resiniorfth@ like;A having: a vvent i passage 235 nextending through the mounting 34 and connecting ithei fatmosphere :with an airfchamber-Jsituatedi on 'the' 4forward ,-'face 4:of i the-switch-:.153:A A flexible: diaphragm 31 --whichs is. .mountedk vonithe forward `face of the switch '33 -lbyscrews ,-139 nar-l ries a contact member:38imaintainedrnormally in Vspaced relationship toan ,electrical connector 53"threaded:throughthe-.mountingf34n :A sec.- ond'A electrical connector-.54 .-.is threaded. through the mounting-34making :contact-Withfthe flex--Y ible diaphragm: 31 at'its periphery: Electr-icoonductors'; 55;. :55:: connected 1 to ,Y the-1connectors..y 53 and 54 `extendztoa second.- conventional electrical delay'apparatus56;\one:of thefconductors 55 having' an electric rpower.-sourcei 55a interposed therein. On the: output sideeof .the.delay apparatus 56;: an-electric conducton-.5-'I textendsto the pipe I2 whereit isgrounded, anda secondelectric conductor iaextendsto a conventional-circuit, breaker-.v5 S :and ,arr electrically.v operatedrelief vvalve 60 r which are y connected in l parallel.- The relief valve -E0 fis. of the'. catchiretained ytype which is-,freleasediby operation of .the-solenoid and 'upona dropgin :fluid pressure-causedbythe opening.- of the .jvalve- 60; the-:valve `returns to 4its closed position.

A4 plurality .of electrodes-ti farenpositioned at fixeddistances 'apart on.the-:decelerationtpipe I2 along. itsi full` lengthy. The function: `of the rvelectrodes 6I is to pickupzthe change in magneticeld caused vbyrft'he passage-ofthe projectileandto convey lthis vchange-.to a magnetic.11ux.indicator 62,--. connectedA by conductors .-63 fto .the electrodes 5 I ,c and; havingf a suitable source `of` electricity l(i4 connected'thereto: Anoscilloscopefor Yotheriap.- propriate electrical. indicating.' device. 68 is con- .nectedV to ther-outputI l leads yIi5,-.of -theI :magnetic flux indicator 63, asshown; Byathismethod-the deceleration rateof fthe. projectiles, :can .be f computedwand "the f proper: airzpressure fora .desired rate of 'deceleration-canibe obtained accurately. The timing of the passage of 'the-:projectiles .past the. spacedfistations along .the :pipe- SIZ- can ibe zdone by any-off the-. welleknown' .methodsisuch as using photoeelectricroells; changeinv'fpressure indicators or lelectric "contact: makers."

Inthenormatoperatioii of-:thezdecelera-tionapparatus upon closing the starting switch 21a, the solenoidZB:becomes.energized-:and: tl'les.;va.lve` 2 5 is turnedthereby ytoithefpositi'onushown by'frliigure 1 permitting air under pressureetcgovwfrom the cylinder 2 I, thus forcing the piston 22 toshiftv carrying the main valve I8 to its opened position. Air under pressure then iiows past the main valve I8, through the coupling I9 and into the deceleration pipe I2. The stem 23 secured to the piston 22 likewise shifts carrying the contact sleeve 28 into engagement with the contact arm 30 for setting the electrical delay apparatus 3l into operation. After a delay of predetermined time, sufficient to permit the deceleration pipe I2 to become filled with air under considerable pressure, the electrical delay apparatus causes the gun to be fired. Upon recoil of the gun, at which time the projectile has entered the deceleration tube I2, the bolt 48 on the extension arm 41 of the gate Il slips past the end of the barrel I0, allowing the gate member 43 to swing downwardly into its obstructing position between the gun barrel I0 and the receiving end of the deceleration tube i2. The expanding gases, produced by the firing of the projectile, escape to the atmosphere at the gap between the barrel I0 and the deceleration pipe I 2, and actuate the flexible diaphragm 3l causing the make contact With member 38 to contact the connector 53 thereby closing the circuit to the electrical delay apparatus 56. As the projectile passes the stations at which the electrodes 6I are positioned on the pipe I2, each of the electrodes 6I conveys to the indicators the moment of its passage whereby the deceleration rate may be computed and the proper air pressure for decelerating the projectile can be obtained.

Before the projectile has travelled a substantial distance through the pipe I2, the electrical delay apparatus 56 operates to cause the air pressure relief valve Si) to open and the circuit breaker 59 to open the circuit connected to the solenoid 26 resulting in the closing of the main valve I8. Upon the release of pressure in the deceleration pipe I2, the relief valve automatically closes, and the projectile which has been decelerated is now removed from the pipe I2 by blowing the projectile back through the pipe I2 to the gate member 43 at the open end `of the deceleration pipe I2 by use of air pressure, If the projectile travelled through the full length of the pipe I2 and was stopped in the chamber I3, the projectile i's removed by opening a gate (not shown) in the chamber I3. The projectile on being removed from the apparatus is then sent to the laboratory for observation and analysis. In order to repeat the projectile deceleration test, the main Switch 27a is opened, the circuit opened by the circuit breaker 59 is closed, and the gate member 43 is swung to its upper or non-obstructing position so as to permit a clear passage to the projectile to be fired, and the firing circuit 32a is closed by the switch 52.

While the form of the device herein shown and described constitutes the preferred form of embodiment of the present invention, it is to be understood that other forms might be adopted all coming within the scope of the claims which follow.

What we claim is:

1. A device for decelerating projectiles red from a gun, comprising a tube closed at one end and open at the other end, and a source of com pressed fluid connected to the tube near its closed end, whereby a projectile lred into the open end of the tube is decelerated by the compressed fluid in said tube, and means actuated by recoil of the gun for preventing return of the projectile to the gun.

2. A device for decelrating projectiles red from a gun, comprising a tube closed at one end and open at the other end, a source of compressed fluid connected to the tube near its closed end, and time delay means for use in firing the gun after a predetermined time interval following admission of the compressed fluid into the tube; whereby the projectile is fired from the gun into the open end of the tube only after the pressure in the tube has reached a predetermined Value,r

the projectile being decelerated by said compressed fluid. l

3. A device for decelerating projectiles fired from a gun, comprising a tube closed at one end and open at the other end, a source of compressed uid connected to the tube near its closed end, a valve between said source and said tube, a delay mechanism for firing a gun after a predetermined time interval and means for simultaneously opening said valve and actuating said delay mech-anism, whereby the projectile is red from the gun into the open end of the tube after a time interval whereby the pressure in the tube has reached a predetermined value, the projectile being decelerated by said compressed fluid.

4. A device for decelerating projectiles fired from a gun, comprising a tube closed at one end and open at the other end, a source of compressed fluid connected to the tube near its closed end, a valve between said source and said tube, a delay mechanism for firing a gun after a predetermined time interval following actuation of said delay mechanism, a switch for actuating said delay mechanism, a fluid operated piston controlling said valve and said switch, and whereby said piston simultaneously operates said valve and said switch to admit compressed fluid into said tube and to initiate action of said delay mechanism whereby said projectile fired from the gun into the open end of said tube is decelerated by the compressed uid.

5. A device for decelerating projectiles flred from a gun, comprising a tube closed at one end and open at the other end, a source of compressed fluid connected to the tube near its closed end, a valve between said source and said tube, a delay mechanism for firing a gun after 4a predetermined time interval following actuation of said delay mechanism, a switch for actuating said delay mechanism, a fluid operated piston controlling said valve and said switch, and a solenoid operated valve for controlling said piston, whereby said piston simultaneously operates said valve and said switch to admit compressed fluid into said tube and to initiate action of said delay mechanism whereby the projectile ired from the gun into the open end of the tube is decelerated by the compressed fluid.

6. A device for decelerating projectiles fired from a gun, comprising a tube open at one end, an enlarged projectile receiving chamber attached to the other end of the tube, means for maintaining the gun muzzle in close spaced relation to the open end of the tube and axially alignedtherewith, a source of fluid under pressure connected to said tube near said projectile receiving chamber, a valve between said source and the tube, electrical delay means for firing the gun after the lapse of a predetermined period of time following opening of said valve, and spaced electrical means for indicating the passage of the projectile in the tube for providing data for computing the correct air pressure in the tube to decelerate a projectile sufciently that it comes to rest in said chamber undamaged.

7': nA fdevicecrgdeceleratingzcproi ectiles. red from aegunrcomprisin'g aatubc openiatr'roneiend,

andwfhaving: af projectile receiving; .chamber .at=V

tached to s the other. end; meansgrfor; maintaining theiibarrelgofrsaid gun inispaceda relation tothe open endcof 1 said: tube.-andin axial alignment therewith; means connectingfa; sourcezoffluid under.=pressure to .said-tube fadjacentzsaidcprojectile receiving chamber; a main-lvalvea'mountedin-said lastftmentionedwmeans; valve: operating; means, means forV actuating:saidzmainzvalver to its iopen position, an electrical delay means for'rng-said gunfmeanswoperatiizel-yconnected to;said |valve operating ,meansforenergizing'saidelectrical-def lav: means upon-operationof said valve; pressure responsive: switch. means mounted: onzzsaidf.` tube adjacent-theopen end thereof; a secondielectrical delznfrrrieans'connected to saidswitchtgmeans, a pressure: relief valve#mounted"y in; saidA pipe: ad'-A jacent: said' chamber;` means,- connecting Asaid rlast named:y electrical delayimeans tosaidrreli'ef valve adapted pto opens said? valveg". and' further means connecting :said-second :electrical 'delaymeans` to said switchimeans .forxreturningrsaid main valve to its closed'qiosition;`

8;!1A 'devi-ce: for: decelerating' projectiles Tired romra-gun comprising a tubeopen at'one end, andhaving .a projectile lreceiving chamber attached-to #the otherrend; means: forI maintaining the.E :barrelvo Said gun; inf spacedr relation to 'the' open .end -1 of lisaidtube? and ini .axial alignmentk therewith emeanstconnecting asource 'of uid underipressure to Isaid itube': adjacent said-projecti1e receivingvchamberi amain-,valve :mountedgin said las'ti mentioned(means,A kvalve operating' means,

meansszforf actuating said imainxvalve to" its open position;:antelectricalErdelayfmeans for ring saidI gum-means operatively connected: to saidvalveoperating meanscforizenergizingranelectrical de--A layimearrsxy uponnoperationnof :said valve, pressure: responsive switch means mountedaonzisaidtube adiacentiA the v,open .endfthereoh a: second electrical delayimeans:` connected .tov` saidf switchi means; a pressure relief 'valvez mountedfin zgsaid' pipe.` ad'- ja-cents;ichamberrrmeansr connecting. saidlast namedf electrical delay fmeansgto said vrelief valve adapted-.i .to z open said: valve; and further means connecting. said1second:.electricalxielay i means to said-switch meansz for returningfsaid main-.valveto'aitsiolosed positionfandizgateameans mountedin' thefsnace;:betweenersaidibarsch-and saidltubezpo.-

sitinnednormally out'.ofthexpath'.of` the iired'; pro-f jectile adapted uporrrecoillof the gun to become positio1iedxi1`11said; path;

ofctlregun-andrthereupon in turn freeing'. the gate to fclose :saidzopen end vrof'tl'ie tube.

l0; A ,deviceefor -decelerating projectiles lflredf ironica-gun', comprising a tube closed `at one. end: and r openiat the .other end, said. open-4 end iacing^- themnzzlezofqthe. gumto receive 'the said vprojece tiles,l a sourcefof compressed fluid fordecelerating-A the proiecti1es, a conduitv forrconvey-ingtsaid iiuid.

to: tha:tuba electrically-v actuated fmeans. controlling the. fowi of the'fluid'-through `said conduit a4 pressureeresponsiveelectrical switchiad'j acentthe muzzleioff. the gun and operative -to control the. circuitv.tov said electrically actuated Qiiovvvcontrol` means,.to.admitfthe -uid tofthe pipe vvhensub.- jected to thevpressure ofthercombustion gases escapingl Krom said muzzle uponfring-thergun:

ll. A device as dened in claim 10, whereinthei electrical..switchzcomprises a, diaphragm carrying a relatively-movable contact ini cooperation with anzadjustable relatively stationary ,contact CHARLES .T. G.. LOONEY. LYNN G.. HOWELL.; BRUCEAG..JOII.NSTON.

REFERENCES .CITED Theffollowing references` arerof record-in the.` file; tof this patent:i 1

UNITED S'lIHf-'FIESvv PATENTS Number t. Namen Date 2,356-,992 y Giisonv Aug.,4 29, 1944 2,400,189 Carlsonzet al May 14,1946- '233.433.491y Cohen.; Jan. 1&1948