US2682223A

US2682223A - Timing mechanism

Info

Publication number: US2682223A
Application number: US662948A
Authority: US
Inventors: Walter E Lewis
Original assignee: US Department of Navy
Current assignee: US Department of Navy
Priority date: 1946-04-18
Filing date: 1946-04-18
Publication date: 1954-06-29
Anticipated expiration: 1971-06-29

Description

June 29, 1954 Filed April 18, 1946 w. E. |-:w|s 2,682,223

TIMING MECHANISM 2 Sheets-Sheet l 42 3 f 7 K l 17 I L l 1 y l M o o A WITNESSES: INVENTOR 45 l l a/fer flew/Is.

ATTORNEY June 29, 1954 w. E. LEWIS TIMING MECHANISM 2 Sheets-Sheet 2 Filed April 18, 1946 .J. mm W N m 5 mr {Mn 9 A B f e; w

WITNESSES: AQMQ Patented June 29, 1954 UNITED STATES PATENT OFFICE TIMING MECHANISM Navy Application April 18, 1946, Serial No. 662,948

14 Claims.

My invention relates generally to detonating devices for explosive charges and more particularly to arming mechanisms for use on torpedoes.

Since a loaded torpedo is a rather dangerous machine safety features to prevent premature firing of the charge of explosive in the warhead are of utmost need. The more complicated such safety devices are the more likely some elements may fail with the result that the charge of v explosive may be detonated prematurely or may not be detonated when desired. Further, it is of importance that the arming take place only after the torpedo is a given distance from the launching location.

One broad object of my invention is the provision of a unitary arming mechanism that may be installed either before or after the warhead is charged with the explosive.

Another broad object of my invention is the provision of a unitary arming mechanism that the switch, which closes a set-up circuit to the squibs which fire the exploder, is operated independently by a worm gear arrangement on the torpedo propeller shaft. In effecting these operations, the wires which lead to the squibs in the exploder from the switch are being coiled and pulled up when the exploder arms, making the wires subject to breakage.

It is a specific object of my invention that the arming switch, which closes the set-up circuit in the leads including the squibs be selfcontained in the exploder and that it be an integral part of the mechanism which arms the firing charge so that the exploder may be armed electrically and mechanically at the same time through the operation of one group of self-contained mechanisms.

It is also a specific object of my invention to provide a direct grounded short-circuit while the exploder is in the unarmed position, for the squibs so that static charges or leakage currents do not accidentally fire the squibs.

The objects of my invention hereinbefore stated are merely illustrative of still other objects and advantages of my invention, which other objects and advantages will become more apparent from a study of the following specification and the accompanying drawings, in which:

Figure 1 is a sectional view substantially to full scale and on a vertical plane of my arming mechanisms;

Fig. 2 is a sectional view to a smaller scale, on section line II-II of Fig. 1;

Fig. 3 is a sectional view to a smaller scale on section line III-III of Fig. 1;

Fig 4 is a broken out portion, some parts in section, of the gear train between the impeller wheel and a certain element of the arming mechanism, and v Fig. 5 shows the circuits controlled by my arm- 1 ing mechanism.

* ture in the warhead of a torpedo (elements not shown). The substructure per se forms no part of this invention. For the purposes of this disclosure, it will suffice to mention that the impeller wheel 2, the bearings for the impeller wheel shaft 3, the gear 4 on the shaft 3 and the worm 4 are all mounted in the sub-structure. The impeller wheel is so mounted that the flow of the water past the torpedo drives the impeller wheel, as shown in Fig. 4, in a counterclockwise direction. Operation of the impeller wheel 2 drives shaft 5 in the direction indicated. Shaft 5 passes through base I through suitable liquid seal devices so that sea water is prevented from leaking into the warhead, that is, into the region above the base I.

Four suitable columns 6, l, t and 9 are at the bottom bolted into the base I and at the top similarly secured to the bearing cradle Iii. The cradle ID carries a bearing ring H rigidly secured to the cradle. The ring H is provided with an annular groove for receiving the ball bearings [2. An annular gear wheel I3, having a mating groove for the ball bearings, is disposed directly above the bearing ring ll.

The annular gear Wheel [3 has a depending annular fiange [4 provided with a radially projecting portion, or rib I5. The flange l4 fits closely about the bearing ring H. Any lateral thrusts will thus not dislocate the gear Wheel with reference to the fixed cradle. Suitable set screws or other similar means, which do not appear in the section shown, protrude radially inwardly from the upper annular edge of the cradle so that they project above the rib l5. The gear wheel is is thus positively retained in position on the cradle It, but is free to rotate with reference to cradle I ii.

A generally cylindrically shaped housing I6 having an annular flange I? at the bottom i bolted to the gear Wheel I3 by the bolts I8. The upper end of the housing is provided with a threadedwopening I9 receiving the externally threaded plug nut 25. The plug nut 29, when in the position shown in full line in Fig. 1, thus seals off the interior of the chamber formed by" It, gear I3, bearing ring :11, and

the housing cradle I 0.

The booster charge 2| is ,disposed inthe position shown in the can 22. Thecan 22 is soldered or brazed to the plug nut and at its downward- 1y projecting flange is secured by a slip-joint against rotation to the housing-23.1:for:the.squibs above and about. casings! 6; Accidental firing of the=booster charge 2| beforethemechanical arming is complete will merely build up aiteinporary pressure .within the chambeinformed byithe housing l6, gear Wheel I3, bearing ring ;I I and :cradle Ifl.: By the time theuhot gases have leakedout ofxthechamber through such. channels as 25: and 21, their eiiectivenessto explode the maincharge ofxexplosive" have largely been. dissipated.

Since mechanical. isolation' .of- 'the booster chargeibefore the mechanicalra-rmingis complete may not suflice, I ELISOHPIPOVidB safety'features to prevent. electrical arming of the ,squibs ,24 before themechanical;arming-has taken place. The squibs Mare in a .circuit'ziigroundediand short circuitedtby contacts :29 and- ;3llacontacting the base I as longas the (mechanical arming has not progressed to a certain extent. Anystaticcharges that .might develop in thezcircuit zBiorany leakage currents are thus effectively-prevented from firing the squibs as longas-the short circuit is maintained.

The hcusing zll, and thus the squibs 2d, are mcunted'onthe piston assembly 5| having the piston rod 32. At the bottom of .the'piston rod .32 I secure block of insula-tion'ii-i carrying the resilient-contacts 29 and-.fiflmsecured respectively to the terminals ofthewsquibs; vThe blockof insulation 33 also carries the resilient contactstfi and 30.". similarly connected to the :terminals of the squibs As long asithe piston rod 32 is all the Wa -down the contacts .28 and short-circuit and ground the squibs'zt'but asisoon as:the rod 32 moves up a selected-distance, the squibs are on open circuit.

The-firing circuit includes a battery B, lead 34, contact 35,- inertia member 36; lead 37, contact 38,icontact 3Z1, thecircuit ZB-including the squibs 2d contact 35!, contact 29'- and lead 4!!! to the battery. To provide a compact structureone that-maybe readily mounted in the warhead and removed therefrome-I secure the leads 3'! and 4G to contacts 38 and fia -respectively, as shown. These leads 3? and r ill are carriedzinto the bottom of theelectric plug '4Imounted .in .-a suitable bracket 42 bolted to the warhead. The electric plug 4| comprises male and female sections so that leads 31 and til may be readily plugged into the firing circuit or removed therefrom all from the side occupied by base I. The whole arming structure may thus be readily removed from the torpedo:

The contacts 35 and "39 are secured to the cradle It b suitable blocks of insulation 43 and The block of insulation 33 is provided with the-projections 45 and t6 engaging columns I and 8 respectively. The vertical movement of contacts fiii and 39 is thus guided so that when the-contacts are-all the way up, they will engage, respectively,-the

contacts

39 and 38.

Before the torpedo is launched, all the elements yin ;.the;;po.sition shown in full line in Fig. 1. After, launching of the torpedo, the propulsion equipment-starts and the torpedo then proceeds through the water toward the target. The flow ofthes water. past :thetorpedd: actuates' 'thedmpeller-wheel 52.. This'zimpellerwheel drives the shaft :5 through the gear I trainsalr-eady, explained. Shaft 15 operates gearsit i, it, M3558 and ;I 3:in the directions indicated... Rotation of gear I3 drives; thehousing:Ifi-andasa consequencethe-plug ;nut- Zfitbeginsito-movesupcarrying the contacts .2 9. and

Hand 29 and 3G upwardly.

After :the iztorpedorhas :movedva selected relativelyshortdistance-irom .thewlaunching position;

theaccntacts. 2913111214319 imove away from the (base I to:thus;remove thezshort-circuitfrom .thesquibs and. putting the: squibs on open circuit. 1

After the torpedo has moved a relativelytlarge distancevfrom:thalaunchingmosition, the contacts 29- 2.116130 engage. contacts :39 and 38; respective- 1y.v Amoment later, "sincecontacts 29- and-:38:

are resilient, the chargenfl'i. is .in the-top position and lug :-25 .-mainta-ins the. mechanical (arming, whereaswthe contactsfiQV-and 3W maintain thez-electrica-l arming; As soon thereafter-as the torpedo strikes :its :target, the inertia switch or member :fifiamoves in :COlltEtOtwith i the contact memberqa 5;'yTheisquibs'arerthus connected to the battery: Thesquibs explode the charge -2I.which ripsizthe can from its SlipyjOlIlt. The effect 'of the explosion :Of charge ,2 I- is thus icarried toithemain charge of explosive and ,-in consequence the main charge of :explosive isi-detonatedi -While :I .have "described :but one preferred em bodiment of: my invention, I do not -.wish to :be limited (to the exact showing made but wish to be limitedponly by the .scope of the claims hereto appended.

I claimasmy invention:

1. In an arming device for a torpedo, in "combination, a base fixed-to the torpedo, an inverted cup-shaped member disposed in rotatablerelation to the base and forming with the base a substantially sealed off chamber, a plug-nut secured in the top of the member having threaded engagement with the member, said plug nut being fixed againstrotation with referenceto the base but having free translatory motion whereby rotation of said member in agiven direction willcausesaid plug-nut to move out of the membQI'xtO provide an opening from .the chamber to the region-outsideof the chamber, means for rotatingv .the :member in the said given direction, a detonator.so. -mounted .on the plug-nut to be in the chamber when .the plug-nut is in threaded engagement with the memben'andmeans for electrically arming the detonator at substantially .thesame time rthe'chamber is opened to the outside by the unscrewing of the plug-nut from the member.

2. In an arming device for a torpedo, in combination, a sub-base secured in an opening in the side wall of the warhead of a torpedo, said sub-base sealing the torpedo warhead against leakage of water into the warhead, an impeller rotatably mounted in the sub-base, rotary motion transmitting means extending through the sub-base from the impeller to the inside of the warhead, a base in the Warhead fixed in spaced relation to the sub-base, a member rotatably mounted on the base, said rotary member being so shaped that together with the base a closed chamber is formed, a detonator of the electrically actuated type in the closed chamber, a traveling nut forming a closure for the chamber, means for restraining said traveling nut against rotation, transmission means between the rotary transmission means and the member for rotating the member to cause said traveling nut to move out of the member to open it to the explosive in the torpedo to thus effect mechanical arming of the torpedo, means operable by the traveling nut also electrically arm the detonator.

3. In an arming device for a torpedo, in combination, a housing consisting of two elements one fixed to the torpedo and the other element fixed on the first element to have rotary motion with reference thereto, a detonator of the electric type disposed in the housing, a traveling nut threaded in the rotary element, means secured to the element of said housing fixed to the torpedo operatively engaging said traveling nut to restrain the said nut against rotation, means for rotating the rotary element as a function of the distance the torpedo travels from its launching position to cause said traveling nut to move out of the rotary element to open the housing to the explosive charge in the torpedo to thus effect mechanical arming of the torpedo.

4. In an arming device for a torpedo, in combination, a housing consisting of two elements one fixed to the torpedo and the other element fixed on the first element to have rotary motion with reference thereto, a detonator of the electric type disposed in the housing, a traveling nut threaded in the rotary element, means secured to the element of said housing fixed to the torpedo operatively engaging said traveling nut to restrain the said nut against rotation, means for rotating the rotary element as a function of the distance the torpedo travels from its launching position to cause said traveling nut to move out of the rotary element to open the housing to-the explosive charge in the torpedo to thus effect mechanical arming of the torpedo, and switching means operable by the traveling nut to cause electrical arming of the detonator.

5. In an arming device for a torpedo, in combination, a housing consisting of two elements one fixed to the torpedo and the other element fixed on the first element to have rotary motion with reference thereto, a detonator of the electric type disposed in the housing, a traveling nut threaded in the rotary element, means, secured to the element of said housing fixed to the. torpedo, operatively engaging said traveling nut to restrain the said nut against rotation, means for rotating the rotary element as a function of the distance the torpedo travels from its launching position to cause said traveling nut to move out of the rotary element to open the housing to the explosive charge in the torpedo to thus effect mechanical arming of the torpedo,

and switching means operable by the traveling nut to cause electrical arming of the detonator, said switching means being so coupled to the traveling nut that the electrical arming takes place substantially at the same time the mechanical arming is effected.

6. In an arming device for a torpedo, in combination, a housing consisting of two elements one fixed to the torpedo and the other element fixed on the first element to have rotary motion with reference thereto, a detonator of the electric type disposed in the housing, a traveling nut threaded in the rotary element, means, secured to the element of said housing fixed to the torpedo, operatively engaging said traveling nut to restrain the said nut against rotation, means for rotating the rotary element as a function of the distance the torpedo travels from its launching position to cause said traveling nut to move out of the rotary element to open the housing to the explosive charge in the torpedo to thus effect mechanical arming of the torpedo, and switching means operable by the traveling nut to cause electrical arming of the detonator, and means for short-circuiting the detonator as long as the traveling nut is in its position in the second element to prevent electric energization of the detonator because of either leakage currents or static charges, or both.

'7. In an arming device for a torpedo, in combination, a housing consisting of two elements one fixed to the torpedo and the other element fixed on the first element to have rotary motion with reference thereto, a detonator of the electric type disposed in the housing, a traveling nut threaded in the rotary element, means, fixed with reference to the torpedo, engaging said traveling nut to restrain it against rotation, means for rotating the rotary element as a function of the distance the torpedo travels from its launching position to cause said traveling nut to move out of the rotary element to open the housing to the explosive charge in the torpedo to thus effect mechanical arming of the torpedo, switching means operable by the traveling nut to cause electrical arming of the detonator, said switching means being so coupled to the traveling nut that the electrical arming takes place substantially at the same time the mechanical arming is effected, and means for short-circuiting the detonator as long as the traveling nut is in its position in the second element to prevent electric energization of the detonator because of either leakage currents or static charges, or both.

8. In an arming device for a torpedo, in combination, a housing consisting of two elements one fixed to the torpedo and the other element disposed on the first element to have rotary motion only with reference thereto, a detonator including a booster charge and a firing squib, said firing squib having a circuit provided at each end with a contact element, a traveling nut threaded into the rotary element, means for restraining rotation of said traveling nut when said rotary element is rotated, means for rotating the rotary element as a function of the distance of travel of the torpedo from its launching position to cause said traveling nut to move out of the rotary element to open the housing to the explosive charge in the warhead to thus effect mechanical arming of the torpedo, said contact elements being connected to said traveling nut to cause electric arming of the firing squib.

9. In an arming device for a torpedo, in combination, a housing consisting of two elements aesaeas.

one fixedto the torpedo-and :the other (element fixed on the first element-to have rotary-motion with reference thereto, adetonator including --abooster charge and a firing squib said firing squib having a circuit provided at each endwith a contact element, a traveling nutthreaded' into the rotary element, said traveling. nut carrying saiddetonator, means for restraining rotation of saidtraveling nut whensaid rotary 'elementis rotated, means for'rotating the rotary element as a function of the distance of travel of the torpedo from its launching position to cause-said traveling nut to move out of the rotary element to open the housing to the explosive charge in thewarhead to thus effect mechanical arming ofxthe torpedo, and-electric supply terminals-for the contact elements fixedly mounted on the element of the housing fixed-to the torpedo,=said contact elements being connected to said traveling nut to thus move into engagement with the electric supply terminals upon rotation of said rotary element to cause electric arming oi the firing squib.

10. In an arming deviceior-a'torpedo, income bination, a housing consisting of two elements one fixed to the torpedo and the-other-element fixed on the firstelement to have rotary motion.

with reference thereto, electric suppiy terminals on the element fixed to the torpedo, a detonatorincluding a booster charge and a firing (squib,

said firing squib having a circuit provided at each end with a contact element, a traveling nut threaded into the rotary element, ,means rigidly coupled to the torpedo and operatively engaging said traveling nut to restrainit against rotation upon rotation of the rotary element, means for terminals that electrical arming takes place at substantially the same time as the mechanical arming is efiected.

11. In an arming device fora torpedo -in com bination, a housing consisting of two elements one fixed to the torpedo and the vother element fixed on the first elementto have rotary motion with reference thereto, a detonator including :-a booster charge and a firing squib, said firing squib having a circuit provided at each end with a contact element, a traveling nutithreadeddnto the rotary element, means rigidly coupled to the torpedo and operatively engaging said traveling.

nut to restrain it against rotation upon "rotation of the rotary element, means for rotating the rotary element as a function of the distance of travel of the torpedo fromits launching position tocause said traveling nut to move out of the rotary element to open the housing to the eX-.- plosive charge in the warhead to thus effect mechanical armingof theltopedo, electric supply terminals for the contact elements mounted on the element fixed to the torpedo and disposed in the path of the contact elements, said contact elements being connectedto -said-traveling nut to move into engagement with the supply terminals to cause electric arming of the firing squib, and. means-fr short-circuiting the contact elements as .long as .the traveling..nut is .in threaded, engagement with the rotary element.

12. .In an arming. devicefor a torpedo,.in.combination, a housing consisting of two elements,

- one fixed to the torpedo and they other element mounted on the first e ement to .have rotary motion with reference thereto, a detonatorim. eluding a booster. chargeand a firing squib,.said.. firing squib having a circuit provided at each end with a contact element, a traveling nutthreade'd into the rotary element, means mounted to bei fixed with reference to. the fixed elementsandn operatively engaging the traveling nutto restrain. rotation of said. nut upon rotation of the rotary. element, means for rotating the rotary element. as .a function of the distance of travel .of the, torpedo from -its.launching position to causesaid traveling nut to move out of the rotary element. to open the housing to the explosive chargein... the warhead to thuseffect mechanical armingof the torpedo, said contact elements being. .con-.-. nected to saidtravelingnut to cause electric arm-,-v ing of the the firing.squib,electric supply termi: nals for the contact elements mounted on the element fixed to thetorpedo and disposed. in the path of the contact elements, said contactelements being so coupled to. thetraveling nut :with, reference to the supply terminals that electrical arming takes place at. substantially the .same timeassthe mechanicalarming is effected and means for slrort-circuiting the contact elements as long as the traveling nut is .in said rotary element.

13. In an arming device for the explosive charge in the Warhead of a torpedo in combination, a sub-base fixediin an opening. in the torpedo warhead to seal the opening, a base fixed in spaced relation on the sub-base by guide means extending from the sub-base to the base, a rod slidably disposed through the base so as to have one end disposed in the space between the sub-base and base and the other endldisposed above thelbasameans on said rod engaging. said guidemeans to efiect only translating motion of said rod, 3, firing squib, a booster charge,

and nut fixed on the end of the rod disposed above the base, electrical supply terminals disposed on the base on .thesurface facing the sub-- base, said .firing squib having a circuit comprising a pair ofleads extending from the terminals of..the firing squib longitudinally of the rod to the endof the rod disposed in the space between the base and the sub-base, contacts on theends of theleads so disposed as to engage the supply terminals upon longitudinal movement of the rod to its upper position, a housing generally of the shape of an inverted cup rotatably mounted on the base, said nut being normally mounted in a threaded opening in the housing, whereby said nut, housing and base form a closed chamber for housing the firing squib and booster charge, an impeller wheel rotatably mounted in the .sub.- basein the path of the water fiow past the torpedo as the torpedo moves through the water, transmission means. between the-impeller wheel and. the housing to efiect rotationof the .housing, whereby the nut is caused to .mcve out ofathe. housing and the booster charge is moved out oi the housing and the contacts on the lower end of the rod make contact with the supply terminals to thus efiect mechanical and electricaLanming and mechanical arming of the warhead l i. In an arming device for the explosive chargein the warhead of a torpedoincombina-z tion, a sub-base of electrical-conducting material fixed in an opening in the torpedo Warhead to seal the opening, a base fixed in spaced relation on the sub-base by a guide means extending from the sub-base to the base, a rod slidably disposed through the base so as to have one end disposed in the space between the sub-base and base and the other end disposed above the base, means on said rod engaging said guide means to guide said rod for longitudinal movement only, a firing squib, a booster charge, and nut fixed on the end of the rod disposed above the base, electrical supply terminals disposed on the base on the surface facing the sub-base, said firing squib having a circuit comprising a pair of leads extending from the terminals of the firing squib longitudinally of the rod to the end of the rod disposed in the space between the base and the sub-base, contacts on the ends of the leads so disposed as to engage the supply terminals upon longitudinal movement of the rod to its upper position, said rod normally being in its lowermost position so that the contacts at the lower end of the rod engage the sub-base to short-circuit and ground the firing squib to prevent firing of the squib by either leakage currents or static charges, or both, a housing generally of the shape of an inverted cup rotatably mounted on the base, said nut being normally mounted in a threaded opening in the housing, whereby said nut, housing and base form a closed chamber for housing the firing squib and booster charge, an impeller wheel rotatably mounted in the sub-base in the path of the water flow past the torpedo as the torpedo moves through the water, transmission means between the impeller wheel and the housing to effect rotation of the housing, whereby the shortcircuit for the firing squib is removed and the nut is caused to move out of the housing and the booster charge is moved out of the housing and the contacts on the lower end of the rod make contact with the supply terminals to thus efiect mechanical and electrical arming and mechanical arming of the warhead.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 880,818 Pangher Mar. 3, 1908 1,340,536 Gathmann May 18, 1920 1,844,575 Harrison Feb. 9, 1932 FOREIGN PATENTS Number Country Date 318,131 Germany Jan. 23, 1920 334,992 Germany Mar. 24, 1921 668,368 Germany Dec. 1, 1938