US2818812A

US2818812A - Fuse

Info

Publication number: US2818812A
Application number: US314757A
Authority: US
Inventors: Donald H Shenk
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-10-14
Filing date: 1952-10-14
Publication date: 1958-01-07
Anticipated expiration: 1975-01-07

Description

Jan. 7, 1958 sHENK 2,818,812

FUSE

Filed Oct. 14, 1952 2 Sheets-Sheet 1 Fig 1- i I FIE- lil- INVENTOR. Dmnuld I-l- Ehenk BY w zzmwuwm ATTORNEYS D. H. SHENK FUSE 2 Sheets-Sheet 2 Filed Oct. 14, 1952 .k wvulv 11.4% L I i m TOR. 7

Enk.

25 INV Donald H.

FUSE

Donald H. Shenlr, Huntsville, Ala,- assignor to the United States of America as represented 'by-the Secretary of the Army Application October 14, 1952, Serial No. 314,757

4 Claims. (Cl. 102'-79) (Granted under Title 35, U. s. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to improvement in fuses.

An object of the invention is to provide a fuse which cannot be detonated in its unarmed position.

Another object of the invention is to provide a fuse which is bore safe.

Another object of the invention is to provide a fuse which will be safe to handle at the end of its flight if the control arms fail to function.

A further object of the invention is to provide a fuse designed for point or graze detonation.

A still further object of the invention is to provide a fuse which will detonate at the end of its flight regardless of whether it strikes a target or not.

A still further object of the invention is to provide a fuse having delayed firing means.

A still further object of the invention is to provide a fuse which is simple in construction and requires a minimum of machining.

Other objects and advantages will-be apparent from the following detailed description and the accompanying drawings, in which:

Figure 1 is a central longitudinal section of a portion of a projectile equipped with a fuse illustrating the present lnvention;

Figure 2 is a longitudinal section of the line 22 of Figure 1;

Figure 3 is a transverse section on the line 33 of Figure 1;

Figure 4 is a transverse section on the line 44 of Figure 1;

Figure 5 is a transverse section on the line 55 of Figure 1;

Figure 6 'is a central longitudinal section of a projectile equipped with a fuse illustrating a slightly modified form of the present invention;

Figure 7 is a longitudinal section on the line 77 of Figure 6;

Figure 8 is a transverse section on the line 8-8 of Figure 6;

Figure 9 is a transverse section on the line 9-9 of Figure 6.

In the drawings, wherein for the purpose of illustration, is shown two forms of the invention, the reference chara'c'2ters 1t) and 10a indicate any form of rotating projectile having a bursting charge 11 and 11a respectively.

Referring'now to Figures 1 through 5. Secured to the projectile by any preferred means, such as-screw threads 12, is a fuse 13. A body portion 14 is cast or machined to provide a tip 15 and a base 16. Extending axially through the body portion from the base 16 to a point near the tip 15 is a bore 17, for receiving a detonator or primer 1% in the inner end thereof.

,t,8l2 Patented Jan. '7, 1958 The outer end of the bore slidably receives a'firing'pin 19'and its propelling spring 20. The inner end'21 of the firing pin is reduced in diameter-"for striking the detonator 18.

Intermediate the inner end 21 of the firing pin and the detonator 18 a transverse slot 22 is formed. The side walls of the slot are grooved to form guide'ways 23 for a barrier member 24 shaped on its edges to slidably lit the guideways. A light spring 25 is seated at its inner end in a socket 26 in the barrier member and at its outer end bears against the wall "of a windshield 28. The windshield envelops the fuse body portion for the usualpurpose.

The barrier member-is normally urged inwardly against shoulders 29 which form the ends of guideways 23' to properly center the barrier member. A seat or indentation 30 is formed in the forward face of the barrier memher in axial alignment with the reduced end 21 of the firing pin. Normally thefiring pin point 21 rests in' the seat 30 and retains the barrier in safe position.

In rotational flight the barrier member will be held against movement by the firing pin until such time as it is released as will be hereinafter disclosed. The barrier member 24 will move outwardly compressing its spring 25 and uncovering the bore 17. A detent 31, square in cross-section and urged forwardly by a spring 32, is slidably received in a slot 33 in the base 16 of thebody portion. A notch 34 formed in the rearward-face of the barrier is positioned to receive thedetent and hold the barrier retracted.

In practice the use of a very light spring 25 is contemplatedand therefore the detent 31 may be found unnecessary. In which event on impact the residual forces in the barrier 24 will hold it retracted long enough for the firing pin to snap into the detonator 18.

Radial slots'35 are formed in the body portion to receive control arms 36. While two arms are shown in the model illustrated, three or more may be used if desired. Each control arm is mountedto oscillate in its radial slot on a pivot pin 37, secured in the'body portion. As the control arms are identical 3. description of one will sufiice for both.

The control arm'36 has a weighted end 38 which is outwardly disposed'with respect to the' aXis of the fuse body and to its other end 39, and forwardly with respect to its pivot pin, for reasons which will be more fully explained. The inner end of the firing pin 19 has formed thereon a shoulder 40 which is normally engaged by an inturned toe 41 formed on the short rearward end 39 of the control arm.

A latch 4-2 provided with a pivot element 43 is rotatably received in a bore-in the body portion. Adjacent thelatch and the short end of the control arm the body portion is cut out to provide a recess Mam-man "the latch may turn. The freeend of the latch is formed with a flat face 45 which engages the abutting face of the short end 39 of the control arm whereby movement of the latch is restrained untilsuflicient-spin'is genera tedto move theoifset'end 38 of control arm outwardly.

The operation of the "invention is as follows:

-In unarmed condition the spring loaded-"firing p'in'19 is restrained by the barrier member 24 which normally closes the bore 17. The end 21 of the firingpin engages the seat 30 and renders the fuse safe.

As herein before stated the center of gravity of each control arm 36 is located forwardly of its pivot axis and in the position of the arms shown up'on Figure l-is radially and outwardly offset from the longitudinal planes through the axes of the respective shafts 37, so that centrifugal force and the forces of set-back both tend to holdthe firing pin safe, that is, in the position of Figure 1, when fired.

When the ends 38 of the control arms move outwardly, consequently the inner ends 39 are moved inwardly and the firing pin point is cammed forwardly away from the barrier member. Continued and increased rotational forces cause the ends 38 of the control arms to move farther outward until the latches 42 are free and rotate under centrifugal force, out of contact with the short ends 39 of the control arms. The barrier member 24 also moves outwardly under centrifugal force of the spinning projectile and is held in outward armed position when detent 31 snaps into recess 34. Thus, in flight, the firing pin is restrained only by the toe 41 of the control arm.

On point impact the sudden deceleration causes the ends 38 of the control arms to move forwardly and inwardly to release the firing pin but the firing pin also moves forwardly from inertia forces causing a delay in firing. The slight delay occasioned by the forward movement of the firing pin allows the projectile to penetrate a short distance into the target before detonation occurs.

When graze impact occurs the resulting deceleration pivots the control arms sufiiciently to release the firing pin and almost instantaneous detonation occurs, thus causing some damage when the impact is too obtuse for penetration of the target.

In case no target is hit, the decay of spin plus the inertla drag forward on the control arms enables the conical end of pin 19, under the thrust of spring 20, to cam the rearward ends of the arms outwardly until the pin is released and driven into the primer to detonate the charge.

Figures 6 through 9 illustrate a modified form of the invention wherein like parts are designated by like reference characters with the addition of the sufiix a.

Secured to the projectile by any preferred means, such as screw threads 12a, is a fuse 13a. A body portion 14a is cast or machined to provide a tip 15a and a base 16a. Extending axially through the body portion from the base 16a to a point near the tip 15a is a bore 17a, for receiving a detonator or primer 18a in the inner end thereof.

The outer end of the bore slidably receives a firing pin 19a and its propelling spring 20a. The inner end 21a of the firing pin is reduced in diameter for striking the detonator 18a.

Intermediate the inner end 21a of the firing pin and the detonator 18a a transverse slot 22a is formed. The side walls of the slot are grooved to form guideways 23a for a barrier member 24a shaped on its edges to slidably fit the guideways. A light spring 25a is seated at its inner end in a socket 26a in the barrier member and at its outer end bears against the wall of a windshield 28a.

The barrier member is normally urged inwardly against shoulders 29a which form the ends of guideways 23a to properly center the barrier member. A seat or indentation 30a is formed in the forward face of the barrier member in axial alignment with the reduced end 21a of the firing pin. Normally the firing pin point rests in the seat 30a and retains the barrier in safe position.

In rotational flight the barrier member will be held against movement by the firing pin until such time as it is released as will be hereinafter disclosed. The barrier member 24a will move outwardly under centrifugal force, thus compressing its spring 25a and uncovering the bore 17a.

Radial slots 35a are formed in the body portion to receive control arms 36a. Each control arm is mounted to oscillate in its radial slot on a pivot pin 37a, secured in the body portion. As the control arms are identical a description of one will suffice.

In this form of the invention, as is indicated by dotted lines upon Figure 6, the control arm 36a, in a normal or unarmed condition, is free to oscillate about its pivot pin within the limitations of a shoulder 40a on the firing pin and the body portion of the firing pin 19g. Consequently one or more of the control arms will be in contact with the shoulder 40a, regardless of the position of the fuse, more certain with a multiplicity of control arms.

The control arm has a weighted end 38a which is disposed forwardly of its pivot pin and outwardly of the rotating axis of the fuse body, for reasons which have been set forth.

At its inner end 39a, the control arm is disposed rearwardly of its pivot pin and inwardly thereof for engaging the shoulder 40a of the firing pin.

At the height of acceleration in the barrel, the outward movement of the control arms is limited by stops 47.

The firing pin is formed with a reduced extension 46 extending a predetermined distance forwardly in the bore 17a, and adapted to limit the forward movement of the firing pin on impact to control the time of delayed firing.

The operation of the modified form of the invention is as follows:

In unarmed condition the spring loaded firing pin 19a is restrained by the barrier member 24a which normally closes the bore 17a. The end 21a of the firing pin engages the seat 30a and renders the fuse safe.

In this modification of the invention the control arms 36a are not restrained by latches 42 as shown in Figure 1. The control arms assume a position in contact with the shoulder 40a of the firing pin on set-back, due to their weight distribution as hereinbefore stated. The barrier member cannot be retracted until sufiicient centrifugal force has been generated in fl ght, to cause the control arms to cam the firing pin into release position.

As the high rate of spin of the projectile during flight moves the weighted ends of the control arms outwardly the firing pin spring is further compressed and held until the fuse contacts a target.

On impact with a target the control arms move inwardly and the firing pin moves forwardly to cause delayed firing in the same manner as set forth in the previous description of the first form of the invention.

The operation of this form of the invention on graze impact and on decay of spin is also identical with that of the first form.

While I have disclosed two forms of the present invention presently preferred by me, various changes and modifications will occur to those skilled in the art after a study of the present disclosure. Hence the disclosure is to be taken in an illustrative rather than a limiting sense; and it is my desire and intention to reserve all modifications falling within the scope of the subjoined claims.

Having now fully disclosed the invention, what I claim and desire to secure by Letters Patent is:

1. In a fuse of the type described, a fuse body having a first longitudinal axis of symmetry and a bore coaxial with said axis, there being a slot in said body transversely of and intersecting said bore between the ends thereof, a firing pin slidably fitting said bore, a barrier member slidably fitting said slot and movable in response to centrifugal force from a first position obstructing said bore to a second position free of said bore, first spring means urging said member into first position, second spring means urging said firing pin rearwardly into position engaging a recess in said member when in first position to hold the same against movement, a control arm pivoted intermediate its ends within said body for movement about a second axis normal to and laterally offset from said longitudinal axis, the centroid of said arm being forward and radially outward of said second axis, a latch member pivotally mounted on an axis parallel with the said first longitudinal axis normally engaging the rear end of said control arm and responsive to centrifugal force to remove from said normal engagement to free the said control arm for said movement about said second axis whereby upon such movement the rearward end thereof engages said pin and moves the same forwardly to release said barrier member.

2. In a fuse of the type described a fuse body having a first longitudinal axis of symmetry and a bore coaxial with said axis, there being a slot in said body transversely of and intersecting said bore between the ends thereof, a firing pin slidably fitting said bore, a barrier member slidably fitting said slot and movable in response to centrifugal force from a first position obstructing said bore to a second position free of said bore, first spring means urging said member into first position, second spring means urging said firing pin rearwardly into position engaging a recess in said member when in first position to hold the same against movement, a plurality of control arms within said body and equiangularly spaced about said first longitudinal axis, each said control arm pivoted intermediate its ends for movement about a second axis normal to and laterally offset from said first longitudinal axis, the centroid of each said arm being forward and radially outward of said second axis, a plurality of latch members within said body, one for each said control arm, and pivotally mounted on an axis parallel with the said first longitudinal axis, each said member normally engaging its respective control arm and responsive to centrifugal force to remove from said normal engagement to free the said control arms for said movement whereby the rearward end thereof engages said pin and moves the same forwardly to release said barrier member.

3. In a fuze of the type described a fuze body having a first longitudinal axis of symmetry and a bore coaxial with said axis, a detonator seated in the rear end of said bore, a firing pin slidably fitted in said bore and spaced from the forward end thereof in normal safe position, there being a slot in said body transversely of and intersecting said bore between the rearward end of said firing pin and said detonator, a barrier member having a seat formed in its forward face for receiving the rearward end of said firing pin and being slidably fitted in said slot and movable in response to centrifugal force from a first position closing said bore to a second position opening said bore, first spring means urging said member into first position, second spring means in the forward end of said coaxial bore urging said firing pin rearwardly into position engaging said seat holding said member in first position, a plurality of centrifugally operated control arms within said body and equiangularly spaced about said first longitudinal axis, each said control arm pivoted intermediate its ends for movement about a second axis normal to and laterally olfset from said first longitudinal axis, the mass center of each said arm being forward and radially outward of said second axis, a plurality of latch members within said body, one for each said control arm, and pivotally mounted on a third axis parallel with said first longitudinal axis, each said member normally engaging its respective control arm and responsive to centrifugal force pivots about said third axis from said normal engagement to free said control arms for said movement whereby the rearward end thereof moves said pin forwardly to release said barrier member.

4. In a fuze of the type described a fuze body having a first longitudinal axis of symmetry and a bore coaxial with said axis the forward end thereof being closed to provide a delay action chamber, a firing pin slidably fitted in said bore and spaced from the forward end thereof in normal safe position, a detonator seated in the rear end of said bore, there being a slot in said body transversely of and intersecting said bore between the rearward end of said firing pin and said detonator, a barrier member having a seat formed in its forward face for receiving the rearward end of said firing pin in normal safe position, said member being slidably fitted in said slot and movable in response to centrifugal force from a first safe position closing said bore to a second position opening said bore, first spring means urging said member into first safe position, second spring means in said delay action chamber urging said firing pin rearwardly into position engaging said seat to lock said member in first safe position, a plurality of centrifugally operated control arms within said body and equiangularly spaced about said first longitudinal axis, each said control arm pivoted intermediate its ends for movement about a second axis normal to and laterally offset from said first longitudinal axis, the mass center of each said arm being forward and radially outward of said second axis, a plurality of latch members within said body, one for each said control arm, and pivotally mounted on a third axis parallel with said first longitudinal axis, each said member nor mally engaging its respective control arm and responsive to centrifugal force to pivot about said third axis from said normal engagement to free said control arms for said movement whereby the rearward end thereof moves said pin forwardly to release said barrier member for outward movement under the influence of centrifugal force, and forces said pin into said delay action chamber against the bias of said second spring, said second spring being capable of further compression in said chamber on impact to effect a delay firing period.

References Cited in the file of this patent UNITED STATES PATENTS 1,955,779 Teitscheid Apr. 24, 1934 2,014,393 Mathsen Sept. 17, 1935 2,641,186 Apotheloz June 9, 1953 FOREIGN PATENTS 891,266 France Nov. 29, 1943 928,644 France June 9, 1947