US2421859A - Mechanical time fuse - Google Patents

Description

June 10, 1947. w

MECHANICAL TIME FUSE Filed April 1, 1943 INVENT OR.

ATTORNEY Patented June 10, 1947 MECHANICAL TIME FUSE- Maurice 1%. Whitney, Elmira, N Y.,. assignor to. BendixAviation Corporation, South Bend, Ind a corporation of. Delaware Application April 1, 1943, Serial No. 481,455

I g The. present invention relates toa combined point detonating and mechanical time fuse for explosive projectiles and more particularly projectilesto be discharged: from rifled cannon.

For certain types oi artillery service,.it is desirable to control the detonation of projectiles by a timing device, and to'a-lso' provide for detonation by impact on the target irrespective of the elapsed time interval.

Various methods have been. proposed for securing the desired results, but the structure heretofore disclosed has in general been subject to the disadvantages. that. the. timeicontrol had to be considerably modified to incorporate the contact detonator, and the attendant complication has tended. to reduc the efficiency of each of the component controlling devices...

It is an. object of the present invention to provide a novel contact and time controlled fuse which is efiicient and reliable in operation and simple in construction.

It is another object to provide such a device in which the incorporation of the contact detonator involves no modification of the operating mechanism. -of the time control.

It is another object to provide such a device in which there is a minimum of time lag between the actuation of the contact fuse and the ignition of the base charge of the projectile.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a vertical substantially mid-sectional view of the nose of a shell showing a preferred embodiment of the invention and;

Fig. 2 is a section taken substantially on the line 2-2 of Fig. 1.

In Fig. 1 there is illustrated the upper portion of a shell I of conventional form containing a base charge 2 and having a threaded opening for receiving a closure plug and adapter 3 which serves to confine the base charge in the shell and is internally threaded to provide a seat for the base 4 of a timer mechanism for controlling the ignition of the charge 2.

The base 4 of the fuse is formed with a cylin- The timing mechanism may be. of any conventional form such, for instance, as the type illustrated the patent to Junghans. Number 1,693,516,. and has at its. upper end a. skeleton timing disk Lt adapted tolhe rotated by the gearing of the clock-work in v order to control the detonation ofv the shell.

The lower end of the. base 4 of the fuse is provided. with a chamber [2 in which is mounted an annular-powder bag l3-which is retained by a plug l4 threaded in-said base and provided with a passage l5 adapted to connect with a. passage 16. through the adapter 3'. which communicates with. the. interior of the shell holding. the base charge 2..

According to the present invention a contact detonating mechanism is placed in. the nose of the fuse and. is. arranged. to causev the. sh ll to explode upon. impact of the fuse with a. target. As here shown this mechanism comprises a firing pin [T slidably mounted in a bearing member 18 in position to strike a cap [9- of suitable fulminating material, carried in a threaded bushing 2]... Primary explosive charge 22 is mounted in the nose of the fuse beneath the cap ls 'and directly above the retainer 1' of the timing mechanism which is provided with an opening 24 permitting the flame from the primary charge 22 to penetrate the time fuse mechanism. An explosive pellet 23 is mounted in the bushing 2| adjacent the cap l9 so as to be exploded by the cap to thereby ignite the charge 22.

In order to permit the flame from the charge 22 to reach the powder bag l3, the top plate 20 of the casing for timing mechanism 6 is provided with apertures 30, and said casing has axially extending channels 25 so formed therein as to register with passages 26 provided in the based of the fuse to connect the socket 5 thereof with the powder bag chamber l2.

In order to prevent premature or undesired actuation of firing pin [1, locking means therefor is provided in the form of a pair of latch members 21, 28 which normally engage beneath a shoulder 29 of the firing pin to prevent its being projected into engagement with the cap IS. The latch members 21, 28 are yieldably held in normal position by suitable means such as a spring 3|, but are movable by centrifugal force radially outward so as to free the firing pin and thereby arm the fuse.

The fuse is enclosed by a casing member 32 of the usual ogive form which is retained on the fuse by any suitable means such as by tongues 33 pressed inwardly to engage beneath a flange that the firing pin I1 is prevented from engaging the cap I9 by the locking members 21, 28; (When the shell is discharged from a rifled gun, the.

rotation of the shell caused by the rifiing causes the members 21, 28 to move radially thus releas-.

ing the firing pin l1 and rendering the fuse sensitive to impact.

If the timing mechanism is so set as to be operative prior to impact on the target, the shellwill be exploded thereby after the predetermined time interval has elapsed. However, if the shell contacts the target earlier than expected; the impact against the target will cause the firing pin I! to engage and fire the cap I9 which in turn ignites the primary charge 22. Flame from the charge traverses the opening '24 of the retainer I, passes through the openings in the timing disk I I into the passages 25, and through the passages 26 into the powder bag chamber I2, thus igniting the powder bag I3, the flame from which passes through the opening I6 into the base charge chamber and ignites the charge 2.

Itwill be seen that the two detonating devices operate independently and without requiring modification of their operating mechanism in order to accomplish the dual form of control. Moreover since the connection from the contact fuse to the powder bag I3 is accomplished by means of flame propagation rather than by any mechanical device involving inertia, there is a minimum of time lag between the actuation of the contact control and the ignition of the base ch'arge.

Although but one embodiment of the invention has been shown and described in detail, it will 4 be understood that other embodiments are possible and various changes may be made in the form and arrangement of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is: I

In an explosive projectile for rifled cannon, a compound fuse comprising a base having a cylindrical socket, a time control mechanism seated in the socket comprising cylindrical casing,

operating gearing mounted therein and a perforated timing disc outside of the casing, a cupshaped retainer enclosing the time control mechanism and holding it in the socket, said retainer having an opening above the disc, a contact igniting device including a primary charge mounted in the fuse above the time control mechanism, and a secondary charge for igniting the base charge of the projectile in said base beneath the socket; said cylindrical casing having axially arranged exterior channels communicating with the space beneath the timing disc, and the base having openings registering with the channels thereby completing passages for conducting the fiame from the primary charge through the openings in the retainer and timing disc to the secondary charge.

' MAURICE P. WHITNEY.

REFERENCES SJITED The following references are of record in the file of this patent:

. UNITED STATES PATENTS Number I Name Date 1,462,314 Woodberry July 17, 1923 1,567,232 Brayton Dec. 29, 1925 2,236,495 Birkigt Mar. 25, 1941 2,190,157 Junghans Feb. 13, 1940 2,183,073 Honger Dec. 12, 1940 1,312,112 Groff Aug. 5, 1919 FOREIGN PATENTS Number Country Date 272,226 Great Britain 1928 308,499 Germany Oct. 13, 1919

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