US3306207A - Coaxial safe and arm device - Google Patents

Description

Feb. 28, 1967 G, H, BECKER ETAL 3,306,207 v COAXIAL SAFE AND ARM DEVICE Filed Oct. 22, 1965 6 Sheets-Sheet l .INVENTORS GERALD H. BECKER DOM/NICK C. LUCENT/ EM o. W

ATTORNEY FIG. 1

Feb. 28, 1967 BECKER ETAL COAXIAL SAFE AND ARM DEVICE 6 Sheets-Sheet 2 Filed 001:. 22, 1965 ON m:

i m9 m2 mm 1 Q2 N2 N2 m: 8 we 01 awn wm om 0 09m 0mm 2 vm on INVENTORS GERALD H. BECKER DOM/NICK C. LUCENTI ATTORNEY Feb. 28, 1967 BECKER ET AL 3,306,207

COAXIAL SAFE AND ARM DEVICE Filed Oct. 22, 1965 6 Sheets-Sheet 5 3 EQ N 55 9mm 39x I 5 N Go 39 may 39 all 9% 35 $9 0 29:6: Ham @9 9 QOQJ now; c 00. mm mu u 8 5:5 EQ 39 Q2 89 II. E m NQNH :09 m $9 7 Q0: 00: no: 3: 0: 3: 2E E9 #63 2% z wt fi IN V EN TORS GERALD H. BECKER BY DOM/NICK C. LUCENT/ ATTORNEY Feb. 28, 1967 BECKER ETAL 3,306,207

COAXIAL SAFE AND ARM DEVICE Fild Oct 22, 1965 6 Sheets-Sheet 4 E O A (D a. 5 5 2 I g Qj s C Q 3 [L m 8 s a Q g] cu u) a 9 g; d 5 j Q' T ,-J 0 g 8 S g .c 8 g N g 8 m g 5 b F 9 m g 3 III! g E J 5.x w o E 3 61 9 +3 3 0 m m Q g 5 Q s u.

Q o o v l 2 g N 8 w w 8 :5 Q P- g Q g u D O E E 2 a (D JNVENTORS GERALD H. BECKER DOM/NICK C.LUCENTI Edda-K N D- W ATTORNEY Feb. 28, 1967 BECKER ET AL COAXIAL SAFE AND ARM DEVICE 6 Sheets-Sheet 5 Filed Oct. 22, 1965 N. wE ow2m 35 N 55 5:5 N 55 6o: 5m 8 :8 Q: 39 $9 0 oo: mm m m wool -m 5:5 TEE Fmo a mm INVENTORS GERALD H. BECKER BY DOM/NICKC. LUCENTI ATTORNEY Feb. 28, 1967 G. H. BECKER ETAL 3,306,207

COAXIAL SAFE AND ARM DEVICE Filed Oct. 22, 1965 e Sheets-Sheet 6 ATTORNEY.

Q wE RW MEE VQQ! TKC mm W: .V@ NCU 5: W m v w: w: W c 3: x 1 K 8 C 3: m2 3 LM mm. V9 (/0! we "am @2 N2 m: o w: 9% Pg ow 2 mm n: N: o 7 @m N 8m 3m fin in 5m United States Patent Ofitice 3,306,207 COAXIAL SAFE AND ARM DEVICE Gerald H. Becker, Morrisville, and Dominick C. Lucenti,

Fallsington, Pa., assignors to Thiokol Chemical Corporation, Bristol, Pa., a corporation of Delaware Filed Oct. 22, 1965, Ser. No. 501,367 Claims. (Cl. 102-70.2)

This invention relates to an ignition device and more particularly to an ignition device which can be armed and disarmed from a point remote therefrom.

Briefly described, an ignition device constituting a preferred embodiment of this invention is provided with electro-mechanical means for reversibly rotating two pyrotechnic detonators or sq-uibs within a sealed housing from a position wherein they are respectively out of alignment with two ignition or detonation trains attached to an end wall of said housing to a position wherein they are in alignment with said trains, the ignition device also being provided with switch means that permit said initiators to be separately fired and with a plurality of locking and indicating means that guard against inadvertent actuation thereof.

It is a broad object of this invention to provide an improved pyrotechnic actuator.

Another object of the invention is to provide a safety and arming device that can conveniently be armed and disarmed from a point remote therefrom.

Still another object of the invention is to provide an ignition device having improved means for preventing accidental actuation thereof.

An additional object of the invention is to provide a safety and arming device that is compact, reliable in operation, and adapted to with stand corrosive or other harmful environmental conditions.

Other objects and advantages of the invention will become apparent in the following detailed description of a preferred embodiment thereof, in which reference is made to the accompanying drawings, wherein:

FIGURE 1 is a pictorial view of a safety and arming device constituting a preferred embodiment of the invention, with a portion of the housing thereof removed so that internal components can be seen;

FIGURE 2 is a longitudinal sectional view of the pre ferred embodiment, taken along the plane represented by line 22 of FIG. 1;

FIGURE 3 is a cross-sectional view of the preferred embodiment, taken along the plane represented by line 33 of FIG. 2;

FIGURE 4 is a cross-sectional view of the preferred embodiment, taken along the plane represented by line 4-4 of FIG. 2;

FIGUR'ES 5, 6 and 7 are schematic representation of electrical components of the preferred embodiment, respectively illustrating the relation of electrical contacts and switches of the device when it is in disarmed, intermediate, and armed configurations;

FIGURE 8 is a longitudinal sectional view of the preferred embodiment, taken along the plane of reference of FIG. 2 after a support member of the embodiment has been rotated 90;

' FIGURE 9 is a cross-sectional view of the preferred embodiment, taken along the plane represented by line 9-9 of FIG. 8; and

FIGURE 10 is a cross-sectional view of the preferred embodiment, taken along the plane represented by line 10-10 of FIG. 8.

Throughout the specification and drawings, like reference numbers refer to like parts.

As illustrated in FIGS. -1 and 2, the preferred embodiment of the invention comprises a substantially cylindrical 3,306,207 Patented Feb. 28, 1967 housing, generally designated by reference number 10, which includes first and second end closures v12, 14 integrally joined to opposite ends thereof, as by means of welding. End closure 12 is provided with a threaded hole '16 that is coaxial with housing 10 and with two additional holes 18a, 18b each of which is spaced from the longitudinal axis of housing 10 and extends from the bottom surface of hole 16 to a point near the inner surface of said end closure. Thus end closure 12 includes two relatively thin wall portions 20a, 20b. Threadedly engaged within hole 16 is a mounting plug 22 in which there are two apertures 24a, 241). A tubular retainer 26a, 26b is positioned in each aperture 24a, 24b, each of these retainers being provided with an integral flange 28a, 28b which is locked between the end surface of mounting plug 22 and the bottom surface of hole 16 when said mounting plug is tightened in hole 16. The outer end of each retainer 26a, 26b is threaded. Each retainer 26a, 26b is also provided with two diametrically opposed, longitudinally extending slots (not shown) at the end thereof which projects outwardly from mounting plug 22, and with a collar 30a, 30b which, when it is screwed on the retainer, reduces the diameter of the aperture 32a, 32b in the retainer at the portion thereof adjacent said slot. Thus, a pyrotechnic train 34a, 34b, such as an ignition fuse of a detonating cord, can be positioned within each aperture 32a, 32b and hole 18a, 18b as illustrated in FIG. 2 and thereafter locked to mounting plug 22 by means of collar 30a, 30b.

Disposed within housing 10 is a support member, generally designated by reference number 36, which comprises a cylindrical casing 38 having first and second end plates 40, 42 integrally joined to opposite ends thereof. More particularly, end plate 40 is disposed adjacent first end closure 12 of housing v10 and includes an integral portion 44 which, as illustrated in FIG. 3, has a generally semicircular cross-section and which projects from the end of casing 38 toward said end closure 12. Portion 44 of end plate 40 is provided with two flat surfaces 46a, 46b, between which is a recessed surface 48, and a first support shaft 50 is fixedly disposed within an aperture formed in said portion 44 and projects from the end surface thereof. As illustrated in FIG. 2, shaft 50 is journalled in a bearing 54 positioned in a hole centrally located in end closure 12 and is thus coaxial with casing 38 and housing 40. Likewise, a second support shaft 58 is fixedly disposed within an aperture 60 formed in end plate 42, projects from the end surface 62 thereof, and is journalled in two bearing 62a, 6217 which are positioned in a hole 64 formed in end closure 14 and which are spaced apart longitudinally thereof.

Disposed adjacent end closure 12 and positioned against the inner, longitudinally extending surface of housing 10 is a curved gear rack 66, this gear being mounted on end closure 12 by means of two screws 68 (see FIG. 3) and spaced therefrom by two spacers 70 through which said screws respectively extend.

As can be seen in FIG. 3, the teeth of gear rack 66 are equidistant from the longitudinal axis of housing 10 and extend over an arc of slightly more than 90. Rotation of support member 36 relative to housing 10 is effected by means of drive means comprising a reversible electric motor 72 mounted within casing 38 of said support member. More particularly, motor 72 is provided at one end with two diametrically opposed, laterally extending support lugs 74a, 74b each of which is secured to end plate 40 by a screw (not shown). The opposite end of motor 72 is fixedly engaged in a hole 78 formed in a partition 80 which extends across the interior of casing 38 and which is joined to the wall thereof. As illustrated in FIG. 2, motor 72 is positioned in casing 39 so that the longitudinal axis of its drive shaft 82 is spaced from, and parallel to, the common axis of support shafts 50, 58. A spur gear 84 is fixedly mounted on the free end of drive shaft 82 and engaged with gear rack 66 so that rotation of said drive shaft causes support member 36 to rotate relative to housing 10.

In FIGS. 3, 7 and 8 can be seen two initiators 86a, 86b (either detonators or squibs) that are respectively mounted in two holes 88a, 88b extending through end plate 40. The axes of holes 88a, 88b are spaced equidistant from the common longitudinal axis of support shafts 50, 58 and are separated by 180. In FIGS. 2 and 3 support member 36 is illustrated in a first angular position thereof relative to housing 10 wherein initiators 86a, 86b are respectively out of register with the ends of pyrotechnic trains 34a, 3412. More particularly, in said first angular position of support member 36, the plane that includes the axes of holes 88a, 88b is disposed perpendicular to the plane that includes the axes of holes 18a, 18b. When support member 36 is in said first angular position thereof a spring-loaded ball detent 89 (see FIG. 3) mounted in a hole formed in portion 44 of end plate 40 is seated in an indentation (not shown) formed in the inner surface of end closure 12, this ball detent preventing movement of support member 36 relative to housing 10 that could result, for example, from vibration of said housing but being adapted to move out of said indentation when motor 72 is actuated to rotate said support member.

In FIGS. 8, 9 and 10 support member 36 is illustrated in a second angular position thereof relative to housing 10 wherein initiators 86a, 86b are respectively in register with the pyrotechnic trains 34a, 34b, the plane that includes the axes of holes 88a, 88b is coincident with the plane that includes the axes of holes 18a, 18b, and one end of each initiator 86a, 86b is disposed adjacent the end of a respective one of said pyrotechnic trains 34a, 34b.

As illustrated in FIGS. 2 and 8, a disk-shaped panel 90 is disposed within housing 10 between end plate 42 and end closure 14, this panel being formed of an electrical insulating material and mounted on end closure 14 by means of screws 92 which respectively pass through spacers 96 and are threadedly engaged with said end closure. FIGS. 5, 6 and 7 illustrate a plurality of arcuate electrical conductors 98 bonded to the face of panel 90 by conventional printed circuit manufacturing techniques. All but two of these conductors are electrically connected by leads 100 to other components of the safety and arming device which are located outside housing 10 and which will be described hereinafter. In FIGS. 5, 6 and 7 panel 90 is seen as it appears when viewed from a plane disposed between said panel and end plate 42 of support member 36, and these drawings also illustrate, in circular cross-section, a plurality of electrical contacts which will be described in detail hereinafter. The structure of a typical one of these electrical contacts is shown in FIG. 8, wherein it can be seen that a typical one of said contacts comprises a housing 102 mounted in an aperture in end plate 42 and a spring loaded pin 106 that slidably contacts, as will be explained hereinafter, at least one of said arcuate electrical conductors as support member 36 is rotated between said first and second angular positions relative to housing 10 and panel 90. Each initiator 86a, 86b is provided with a bridgewire connected by two leads 108a through 108d to two of the pins 106 of the electrical contacts mounted on end plate 42, and as illustrated in FIGS. 5, 6 and 7 three leads 110a through 110c connect motor 72 to the pins of three other of said contacts. All of the leads 180 which are connected to the conductors 98 mounted on panel 90 pass outside housing 10 through one of two seal members 112a, 11% (see FIG. 4) each of which is provided with a seal ring 113a, 113b and with a seal grommet 114a, 114b, said seal members being respectively threadedly engaged in the outer end of L-shaped passages 116, 118 formed in end closure 14 so as to extend between the outer surface thereof and a cavity 119 (see FIG. 2) located in said end closure adjacent panel 90.

Mounted on support shaft 58 is a spur gear 120 which is held in fixed position by a pin (not shown) that extends through holes formed in said support shaft and spur gear. A cylindrical spacer 124, 126 (see FIG. 8) is also mounted on support shaft 58 between spur gear 120 and each of the bearings 62a, 62b in which said support shaft is positioned, and a retainer 128, attached to end closure 14 by a screw 130, holds the support shaft and its bearings, spacers and spur gear in place. A horseshoe clip 132 attached to the end of support shaft 58 facilitates assembly of these components as a unit within hole 64 in end closure 14. As can be seen in FIG. 10, end closure 14 contains a hole 134 which extends from the bottom surface of hole 118 to the opposite side of said end closure and which communicates with hole 64. Fixedly positioned in hole 134 is a cylindrical insert 136 having an integral flange 138 at one end thereof, this flange being seated against the bottom surface of hole 118. An opening 140 is formed in the wall of insert 136 adjacent flange 138 so that spur gear 116 can engage a gear rack 142 slidably mounted in said insert. A portion of gear rack 142 projects laterally from end closure 14 and a transverse member 143 is integrally joined to the outer end of said gear rack and to one end of a bellows 144 which is positioned around the projecting portion of said gear rack. The other end of bellows 144 is fixedly connected to a cylindrical member 146 that is in turn attached to end closure 14 by means of plurality of screws 148. To seal the interior of bellows 144 and housing 10, a seal ring 149 is disposed between end closure 14 and member 146. A cap, generally designated by reference number 150, is adapted to be detachably connected to the outer end (i.e., the end remote from end closure 14) of member 146 by means of a bayonet connection between slots 152 formed in said cap and a plurality of pins 154 fixedly mounted in holes in said member 146 so as to project perpendicularly from the outer surface thereof. When cap is moved into engagement with member 146, a centrally disposed projection 156 thereof contacts the member 143 of gear rack 142 and moves the opposite end of said gear rack into contact with -a contact switch generally designated by reference number 158 (see FIG. 4). Spur gear 120 is simultaneously rotated by gear rack 142 so that support member 36 is rotated to the previously described first angular position thereof relative to housing 10. Contact switch 158 comprises a spring arm 160 one end of which is attached to an electrical insulating member 162 and the other end of which is seated against a contact member 164 until the spring arm is contacted by gear rack 142. Contact member 164 is also attached to insulating member 162, which is itself mounted on the flange 138 of insert 136 by suitable means. As will be explained in detail hereinafter, contact switch 158 is electrically connected to one of the arcuate conductors mounted on panel 90 and to components of the safety and arming device which are located outside housing 10.

As pointed out hereinbefore, FIGS. 2 and 3 illustrate support member 36 in a first angular position thereof relative to housing 10 and panel 90 wherein the initiators 86a, 86b are respectively out of register with the ends of pyrotechnic trains 34a, 34b and wherein the plane that includes the axes of the holes 88a, 88b in which said initiators are positioned is disposed perpendicular to the plane that includes the axes of the holes 18a, 18b in which the ends of said pyrotechnic trains are positioned. When initiators 86a, 86b and pyrotechnic trains 34a, 3412 are in this configuration, the safety and arming device is disarmed as indicated by the letter S which is placed on casing 38 of support member 36 so as to register with a window 161 (see FIG. 1) in housing 10, and the aforementioned arcuate conductors 98 mounted on panel 90 and the pins 106 of the electrical contacts mounted on end plate 42 of support member 36 are oriented as shown in FIG. 5. More specifically, pins 106a, 106b are in contact with conductor 9811, with leads 108a, 108b connecting these pins to the bridgewire of initiator 86a; and pins 1060 and 10611 are in contact with conductor 98b, with leads 1080 and 10811 connecting these pins to the bri-dgewire of initiator 86b. Therefore, when the safety and arming device is in a disarmed condition, both of the initators 86a, 86b are shorted by conductors 9811, 98b respectively. Pin 1062 is in contact with conductor 98c, with lead 110a connecting this pin to a first solid state diode 170a that is mounted within the casing of mot-or 72 and disposed so as to pass electric current in the direction indicated by the schematic symbol for the diode. Pin 106 is positioned near, but is not in contact with, conductor 98d, with lead 110b conmeeting this pin to a second solid-state diode 17% that is also mounted within the casing of motor 72 and disposed so as to pass electric current in the direction indicated. Pin 106g is in contact with conductor 9812, with lead 1100 connecting this pin to motor 72. Diodes 1700, 170b are connected to each other and to motor 72 by leads 174a, 174b and 176. In addition, two pins 106b, 1061 are in contact with conductors 98f, 98g and are connected together by a lead 178.

As has been mentioned hereinbefore, all but two of the conductors 98 (namely, conductors 98a, 98b) are connected by leads 100' to components of the safety and arming device which are located outside housing 10. More specifically, it can be seen in FIG. 5 that conductor 98c is connected by lead 10011 to one pole 10801 of a doublepole, double throw switch, generally designated by reference number 182, that can advantageously be located at a point remote from the safety and arming device. It can be seen in the same drawing that conductor 98d is connected by lead to a second pole 18% of said switch. The two switch arms 18411, 184b of switch 182 are respectively connected to opposite ends of a battery 186 or other source of electric current. Conductor 98a is connected by lead 1000 to the third and fourth poles 180e, 18011 of switch 182. More particularly, lead 1000 connects conductor 98:: to contact member 164 of switch 158 mounted within passage 118 in end closure 14, and a lead 188 connects spring arm 160 of said switch 158 to two leads 190a, 190b which bridge the third and fourth poles 1800, 1800! of switch 182. As illustrated in FIG. 5, when the safety and arming device is in a disarmed condition the switch arms 18411, 18412 of switch 182 respectively contact poles 1800, 180b of said switch. It will be seen that pole 180b of switch 182 is thus connected to conductor 981i and, since this conductor is not in contact with pin 106 motor 72 cannot be energized. Furthermore, when the device is disarmed, cap 150 is secured to the end of member 146 and, as has been explained hereinbefore, gear rack 142 disengages spring arm 160 of switch 158 from contact member 164 so that the circuit path between motor 72 and pole 180a of switch 182 is also open. Two leads 100d, 1002 are respectively connected to conductors 98f, 98g and to a circuit that includes an incandescent light 192, preferably located near switch 182, and a battery 194 or other source of electric current. Conductors 987, 98g are electrically connected by pins 106/1, 106i and lead 178, and therefore light 192 is on when the safety and arming device is disarmed. It will be noted that conductors 98h through 98111 are not in contact with any of the pins 106 when the safety and arming device is disarmed.

When the safety and armed device is to be armed, cap 150 is detached from member 146, whereupon bellows 144 moves gear rack 142 a sufficient distance toward the outer end of said member 146 to permit spring arm 160 of switch 158 to contact member 164. The switch arms 184a, 184b of switch 182 are then brought into contact with poles 18011, 18011 of said switch respectively (see FIG. 6) to permit electric current to flow to motor 72 through leads 19% and 188, switch 158, lead 1000, conductor 982, pin 106g, and lead 1101', and from said motor back to the battery through leads 176 and 17411, diode 170a, lead 110a, pin 106e, conductor 98c and lead 10011, as indicated by arrows in FIG. 6. Flow of electric current through motor 72 as described causes its drive shaft 82 to rotate in such a direction that support member 36 is rotated counterclockwise as viewed from the plane designated 33 in FIG. 3. The pins 106 of the electrical contacts mounted on end plate 42 of support member 36 are therefore also moved counterclockwise from the positions thereof illustrated in FIG. 5. In FIG. 6 the relation of the conductors 98 on .panel and pins 106 is illustrated for a position of support member 36 relative to housing 10 that is approximately halfway between the previously described first and second angular positions of said support member. Thus it will be recognized by inspection of FIG. 6 that pin 106], which is not in contact with conductor 9811' when the safety and arming device is disarmed, is rotated counterclockwise and thereby brought into contact with said conductor 9811 when motor 72 is energized to rotate the support member from the first angular position thereof. Rotation of support member 36 also disengages pins 10611, 1061 from conductors 981 98g, thereby turning off light 192 and indicating to an operator that the safety and arming device has been actuated. Motor 72 continues to rotate support member 36 while pins 106e and 106g slide along conductors 98c and 98e respectively. The length of conductor 980 is such that pin 106e disengages from conductor 980 when support member 36 is a short distance from the previously described second angular position thereof relative to housing 10. However, the inertia of support member 36 causes it to rotate after motor 72 is disconnected from battery 186 as a result of disengagement of pin 106s and conductor 98c, and when said support member reaches the aforementioned second angular position thereof, ball detent 89 enters an indentation (not shown) formed in the inner surface of end closure 12, thereby stopping said support member. To further ensure that support member 36 is stopped at the proper position for bringing initiators 86a, 86b into register with the ends of pyrotechnic trains 3411, 34b respectively, a pin 199 (see FIG. 9) is mounted on end closure 12 in such a position that surface 46b of portion 44 of end plate 40 contacts said pin when support member 36 reaches the second angular position thereof relative to housing 10 (see FIGS. 3 and 8). As pointed out hereinbefore, when support member 36 is in its second angular position, initiators 86a, 86b are respectively aligned with the ends of pyrotechnic trains 34a, 34b and the safety and arming device is in an armed condition. As illustrated in FIG. 7, pins 106a, 106b are then respectively in contact with conductors 9811, 981', which are connected by leads 100g to a circuit including a switch, generally designated by reference number 196, and a battery 198 or other source of electric current. Likewise, pins 1060, 10611 are respectively in contact with conductors 98f, 98k, which are connected by leads 10011, 1001 to a circuit including a switch, generally designated by reference number 200, and a battery 208 or other source of electric current. Obviously switches 196, 200 can be located at a point remote from housing 10 and can be closed at any predetermined time to actuate initiators 86a, 86b either separately or simutlaneously. The gases generated by said initators 86a, 86b rupture the thin wall portions 20a, 20b of end closure 12 and either ignite or detonate pyrotechnic trains 34a, 34b depending upon the material of which said trains are formed. It can also be seen in FIG. 7 that in the armed condition of the safety and arming device pins 106b, 1061 are respectively in contact with conductors 981, 98111 which are connected by leads 100i, 100k to a circuit including an incandescent light 204, preferably located near light 192 and switch 182, and a battery 206 or other source of electric current.

7 Since pins 10611, 106i are bridged by lead 178, light 204 is on when the safety and arming device is armed. Also a letter A is located on casing 38 of support member 36 so as to appear at window 161 when said support member is in the second angular (or armed) position thereof relative to housing 10.

If it is desired to rotate support member 36 from the second angular position to the first angular position thereof relative to housing 10 to thereby ensure that pyrotechnic trains 34a, 34b cannot be ignited or detonated by initiators 86a, 86b, an operator can return switch arms 184a, 18412 to poles 180b, 1800 of switch 182 (this position of said switch arms being illustrated by broken lines in FIG. 7), whereupon electric current will flow from battery 186 to motor 72 through lead 100b, conductor 98d, pin 106), lead 110b, diode 17012, and leads 174th and 176, and from motor 72 back to said battery through lead 110e, pin 106g, conductor 982, lead 10%, switch 158, and leads 188 and 190a (the direction of this current flow :being illustrated by broken line arrows in FIG. 7). Since the direction of current flow to motor 72 is opposite that shown in FIG. 6, the motor is energized to rotate its drive shaft 82 in a direction that returns support member 36 to the first angular position thereof relative to housing 10. It will be understood by the foregoing description of FIG. that the inertia of support member 36 causes it to continue to rotate after pin 106 is disengaged from conductor 98d, motion of said support member being arrested when ba-ll detent 89 enters the indentation in end closure 12 that cooperates with said ball detent to hold the support member in the first angular position thereof. As can be seen in FIG. 3, surface 46a of portion 44 of end plate 40 contacts pin 199 when support member 36 reaches its first angular position relative to housing 10.

It will be apparent from the foregoing description of the preferred embodiment of the invention that the invention provides a safety and arming device Which can convenienly be armed and disarmed from a point that is remote therefrom. Furthermore, by simply attaching cap 150 to the device, an operator can rotate support member 36 so that the initiators 86a, 86b mounted thereon are removed from register with the pyrotechnic trains 34a, 34b, thus ensuring that said trains cannot be ignited or detonated while he is near the device. Other advantages of the disclosed safety and arming device include its sealed construction and compactness, and its adaptability for use where more than one initiator must be included in an actuator to increase its reliability. It will also be apparent to those skilled in the art of pyrotechnic actuators that various modifications can be made in the disclosed safety and arming device without departing from the scope of the invention, for the limits which reference must be made to the appended claims.

What is claimed is:

1. A safety and arming device comprising:

a housing having an end closure at each end thereof;

at least one pyrotechnic train having one end thereof connected to said housing;

a support member mounted within said housing for rotation relative thereof; a curved igear rack mounted Within said housing; drive means comprising a reversible electric motor mounted on said support member and a gear mounted on the drive shaft of said motor and engaged with said gear rack, whereby said support member is rotated between first and second angular positions thereof relative to said housing when said motor is operated;

an initiator mounted on said support member so as to be respectively out of and in register with the end of said pyrotechnic train when said support member is in said first and second angular positions;

an electrically-insulative panel mounted within said housing;

first actuation means comprising a plurality of electrical conductors mounted on said panel, a plurality of electrical contacts each of which is electrically connected to said motor and mounted on said support member so as to slidably contact at least one of said conductors when said support member is rotated between said first and second angular positions, and electrical power supply and switch means electrically connected to said conductors, said switch means being remote from said housing and adapted to selectively pass electric current to different ones of said conductors so that said motor can be energized to reversibly rotate said support member to said first and second angular positions, said first actuation means being arranged so that flow of electric current from said power supply to said motor is terminated when said support member is rotated to first and second angular positions; and

second actuation means comprising a pair of electrical conductors mounted on said panel, a pair of electrical contacts electrically connected to said initiator and mounted on said support member for contact with said pair of conductors when said support member is in said second angular position, and electrical power supply and switch means electrically connected to said pair of conductors, said switch means being remote from said housing.

2. A safety and arming device comprising:

a cylindrical housing having first and second end closures connected to opposite ends thereof;

a pair of pyrotechnic trains each having one end thereof connected to said first end closure;

a support member comprising a cylindrical casing coaxially disposed within said housing, a first end plate connected to one end of said casing and disposed adjacent said first end closure, a second end plate connected to the other end of said casing and disposed adjacent said second closure, and first and second support shafts respectively connected to said first and second end plates and journalled in said first and second end closures, said support shafts being coaxial with said casing;

a curved gear rack mounted within said housing between said first end closure and said first end plate;

drive means comprising a reversible electric motor mounted within said casing with the drive shaft thereof extending through said first end plate and a first gear mounted on the free end of said drive shaft and engaged with said curved gear rack whereby said support member is rotated between first and second angular positions thereof relative to said housing when said motor is operated;

a pair of initiators mounted on said support member so as to be respectively out of and in register with the ends of said pyrotechnic trains when said support member is in said first and second angular positions;

an electrically-insulative panel mounted within said housing adjacent said second end closure;

first actuation means comprising a plurality of electrical conductors mounted on said panel, a plurality of electrical contacts each of which is electrically connected to said motor and mounted on said second end plate so as to slidably contact at least one of said conductors when said support member is rotated between said first and second angular positions, and electrical power supply and means electrically connected to said conductors, said switch means being remote from said housing and adapted to selectively pass electric current to different ones of said conductors so that said motor can be enengized to reversibly rotate said support member to said first and second angular positions, said first actuation means being arranged so that flow of electric current from said power supply to said motor is terminated when said support member is rotated to said first and secmeans for locking said gear rack against said contact nd angular positions; and switch. second actuation means comprising a plurality of elec- 4. A safety and arming device as defined in claim 3 trical conductors mounted on said panel, a plurality wherein:

of electrical contacts, pairs of which are respectively 5 electrically connected -to said initiators and mounted on said second end .plate so as to contact different a portion of said gear rack projects laterally from said second end closure; said means for biasing said gear rack comprising a pairs of said conductors when said support member is in said second angular position, and electrical power supply and switch means electrically connected bellows positioned around the projecting portion of said gear rack and a cylindrical member positioned around said bellows and attached to said second to said conductors, said switch means being remote end closure, said bellows 'being connected at one from said housing and adapted to selectively pass end to said cylindrical member and at the other end electric current to different pairs of said conductors to the outer end of said gear rack; and

so that said initiators can thereby be separately said means for locking said gear rack comprises a cap actuated. adapted to be detachably connected to the outer end 3. A safety and armingdevice as defined in claim 2 of said cylindrical member and a central projection including: connected to said cap so as to contact said gear rack a contact switch mounted on said second end closure and electrically connected to said motor and said first actuation means, said contact switch being adapted, when open, to electrically disconnect said first actuation means from said motor;

a second gear mounted on said second support shaft;

a gear rack slidably mounted on said second end closure and engaged with said second gear, said gear rack lbeing dis-posed so that it can be manually moved into contact with said contact switch to thereby electrically disconnect said first actuation means from said motor; D

means for resiliently biasing said gear rack away from BENJAMIN CHELT, Przmary Examiner.

said contact switch; and W. C. ROCH, Assistant Examiner.

and lock it against said contact switch when said cap is connected to said cylindrical member.

5. A safety and arming device as defined as claim 4 including means for indicating at a point remote from said housing that said support member is in said second angular position.

References Cited by the Examiner UNITED STATES PATENTS 2,954,734 10/1960 Kendall et a1. 102-70.2 3,052,162 9/1962 Rovin 102-702 X

Claims (1)

1. A SAFETY AND ARMING DEVICE COMPRISING: A HOUSING HAVING AN END CLOSURE AT EACH END THEREOF; AT LEAST ONE PYROTECHNIC TRAIN HAVING ONE END THEREOF CONNECTED TO SAID HOUSING; A SUPPORT MEMBER MOUNTED WITHIN SAID HOUSING FOR ROTATION RELATIVE THEREOF; A CURVED GEAR RACK MOUNTED WITHIN SAID HOUSING; DRIVE MEANS COMPRISING A REVERSIBLE ELECTRIC MOTOR MOUNTED ON SAID SUPPORT MEMBER AND A GEAR MOUNTED ON THE DRIVE SHAFT OF SAID MOTOR AND ENGAGED WITH SAID GEAR RACK, WHEREBY SAID SUPPORT MEMBER IS ROTATED BETWEEN FIRST AND SECOND ANGULAR POSITIONS THEREOF RELATIVE TO SAID HOUSING WHEN SAID MOTOR IS OPERATED; AN INITIATOR MOUNTED ON SAID SUPPORT MEMBER SO AS TO BE RESPECTIVELY OUT OF AND IN REGISTER WITH THE END OF SAID PYROTECHNIC TRAIN WHEN SAID SUPPORT MEMBER IS IN SAID FIRST AND SECOND ANGULAR POSITIONS; AN ELECTRICALLY-INSULATIVE PANEL MOUNTED WITHIN SAID HOUSING; FIRST ACTUATION MEANS COMPRISING A PLURALITY OF ELECTRICAL CONDUCTORS MOUNTED ON SAID PANEL, A PLURALITY OF ELECTRICAL CONTACTS EACH OF WHICH IS ELECTRICALLY CONNECTED TO SAID MOTOR AND MOUNTED ON SAID SUPPORT MEMBER SO AS TO SLIDABLY CONTACT AT LEAST ONE OF

Images