EP1397635B1 - Fuse for a hand grenade - Google Patents

Abstract

Accidents frequently occur when handling conventional hand grenades as well as during their transport and/or before their use due to the fact that their safety is insufficient. A considerable improvement is effected by a fuse (1) having three safety mechanisms. When secured, a firing pin piece (22) serving as an impact hammer (21) cannot rotate since its bearing (24) is blocked on a cylinder (50). An ignition likewise cannot occur as a result of an orthogonal displacement of the firing pin (2) with regard to the longitudinal axis (A), said firing pin being located inside a slide (70). As a third mechanism, a safety splint (3) cannot be removed as long as the fuse body (4) is not rotated with regard to the grenade (10) around angle (ss). The manual control of the rotational movement is effected by a locking bolt (60). The cylinder (50) is loaded toward a secured position by a spiral spring (56).

Description

The present invention relates to a detonator for hand grenades according to the preamble of claim 1.

Explosive projectiles in the form of hand grenades are notoriously known, in which a safety pin or split pin, once removed, leads to ignition. To avoid this, the trigger must be pressed firmly against the grenade; after releasing it, a hammer is released and the ignition process is delayed pyrotechnically.

It has often happened that the safety pins or split pins were accidentally pulled (e.g. in the event of a fall or other manipulation), which resulted in serious accidents.

To increase security, a hand grenade (US -A-3,865,027) was provided with a spin-proof split pin, so that it can only be pulled in one position, over a ring. The bayonet-like security, for example, requires a rotation of exactly 90 ° to get into focus - this makes handling the grenade more difficult and, in a stressful situation, makes it necessary to secure it again if the grenade is not thrown for any reason.

Another hand grenade with a security device is known from US-A-3,765,337. The wire lock used as a pull ring here has an essentially rectangular shape and is shaped in two planes and resiliently placed around the hinge of its release lever. The focus the grenade takes place in three steps. First, the part of the ring around the hinge is folded up and thus released on one side, then twisted off to the side and only then pulled vigorously as a third, so that the folded ends of a safety pin are pulled straight out of their mounting hole the hand grenade would only be possible with appropriate tools such as pliers etc.

Another securing grenades is known (US -A-2,737,116 (basis for claim 1)) in which the firing pin with its tension spring is pivoted laterally to the main axis in the secured state. The striking device is only straightened in the effective direction by removing a securing strip, as a result of which the pin is brought into line with the ignition chain. The grenade, primarily intended for firing with rifles, uses a complicated lever system to secure, focus and fire it. In addition, the firing pin is already pretensioned via a spring in the stored state in order to prevent its movement during transport; the spring is additionally tensioned by straightening. - It is not possible to secure again after an unwanted or premature release.

It is therefore an object of the invention to improve the safety and thus the risk of accidents when handling hand grenades. reduce significantly.

The hand grenade to be created should not store any mechanical energy acting on the firing pin in the striking direction in the stored state, which could cause an unwanted initiation of the grenade by a blow and / or drop. The security mechanism should be designed so that a unintentional triggering, for example by accidentally hanging the mechanism on a projecting object is not possible. Furthermore, if the grenade is unsecured for any reason, it should be safe and easy to secure again, even under difficult environmental conditions (cold, wet, etc.) and in stressful situations (preventive defense, combat, etc .).

This object is achieved by the features of patent claim 1.

The subject matter of the invention allows the hand grenade to be brought into focus in the event of a threat and, if it is not used, to return it to the secured position.

The safety mechanisms are designed in such a way that the grenade can be handled even in extreme cold, for example even with heavy gloves.

Preferred developments of the subject matter of the invention are described in the following dependent claims.

The rotatable cylinder can be moved by a spring to the outer end of the eccentrically arranged groove, so that the ignition pin is displaced in the locked state in a secured position relative to the longitudinal axis of the igniter.

A coil spring is kinematically inexpensive and space-saving, the inner end of which is attached to the cylinder and the outer end of which is attached to the igniter body.

The combination of slide and cam in one piece is particularly simple and space-saving

An embodiment of the guide groove for the slide in the form of a curve, preferably as an elliptical curve, requires little space and causes constant and only slight friction between the cam and the groove.

If the firing pin is loaded with a spring against its direction of impact, it remains in its idle state even under vibrations and does not impair the displacement path of the slide.

The design of the hammer as a two-armed lever allows it to be easily locked in the secured state on the cylindrical part of the hollow cylinder.

A lateral milling on the cylinder itself creates its defined angular position for unlocking and releasing the hammer.

In the same way, the locking pin is secured or unlocked accordingly.

It is expedient to unlock and lock the igniter body by means of a spring-loaded bolt which, on the one hand, determines the angle of rotation and, on the other hand, serves as an indication of the state of locking / unlocking.

The design of the detonator bracket with side tabs enables it to be secured in opposite bores that correspond to the safety split pin and at the same time serves as lateral sealing elements for covering the slide.

The shape of the detonator bracket can easily be adapted to the kinematics of the hammer, so that when it is activated it is thrown off during the throw.

The invention and its advantages are illustrated with the aid of drawings of a practically implemented exemplary embodiment and are described below.

Fig. 1

einen vertikalen Längsschnitt durch eine Zündvorrichtung, welche auf einem üblichen Handgranatenkörper aufgeschraubt ist, in gesichertem Zustand,

Fig. 2

eine horizontale Schnittdarstellung entlang der Linie II - II aus Fig. 1,

Fig. 3

eine vertikale Teil-Schnittdarstellung entlang der Linie III - III aus Fig. 1,

Fig. 4

eine horizontale Teil-Schnittdarstellung entlang der Linie VI - IV aus Fig. 3 und

Fig. 5

einen vertikalen Längsschnitt durch die Zündvorrichtung Fig. 1 im entsicherten Zustand, unmittelbar vor der Zündung.

Show it:

Fig. 1

3 shows a vertical longitudinal section through an ignition device which is screwed onto a conventional hand grenade body, in the secured state,

Fig. 2

2 shows a horizontal sectional illustration along the line II-II from FIG. 1,

Fig. 3

2 shows a vertical partial sectional illustration along the line III-III from FIG. 1,

Fig. 4

a horizontal partial sectional view along the line VI - IV of Fig. 3 and

Fig. 5

a vertical longitudinal section through the ignition device Fig. 1 in the unlocked state, immediately before the ignition.

To simplify the discussion of the representations, the cutting planes were referred to as vertical and horizontal planes, although the function of the hand grenade is position-independent - in fact, however, the horizontal plane is a plane orthogonal to the longitudinal axis of the detonator as claimed.

An ignition device according to the invention is designated by 1 in FIG. 1. It is screwed onto a notoriously known grenade body 10, 11, which is indicated by dash-dotted lines and whose vertical longitudinal axis bears the designation A. This longitudinal axis A coincides here with the section line III - III.

An ignition pin 2, which is also known per se, is arranged above a primer 12 and results in a percussion igniter. A detonator bracket 20 is used as the release lever, which is secured here by a split pin 3, see FIGS. 1 and 2.

The detonator bracket 20 is attached to a bearing point 40 (pivot) and can be pivoted about it and contacts the detonator body 4 on its upper end face. The bearing point 40 is formed as a single part and riveted to the detonator body 4 via a connecting pin 8 and a flange 9. 1 further shows an inner leg 30 and an outer leg 31 of the split pin 3, the middle region of an impact piece 22 abutting the outer leg 31. The upper end 24 of the striker 22 lies on the cylindrical portion of a hollow cylinder 50 and is thus secured against rotation; a coil spring 23 is suspended at one end 23b in the striker 22 and loads it. The other end 23a of the tensioned coil spring 22 is inserted into a blind hole in a pin 41. In addition, the striking piece 22 has a lower end, which is designated by 25 and acts as a discharge bow (FIG. 5).

A locking and pull ring 33, by a clamp holder 44 and by an annular arc 32 of the split pin 3, Fig. 2, guided, is used for unlocking before triggering the ignition process.

On the longitudinal axis A of the ignition device 1, a link-like slide 70 is located in a hollow cylinder 50 screwed onto the grenade head 11, in which an axially movable ignition pin 2 is inserted. A spiral spring 56 in an end-side peripheral groove 53 surrounds the hollow cylinder 50, and engages with one end in the detonator body 4 which can be pivoted about its axis A and with the other end on the hollow cylinder 50, cf. Fig. 4. The head 11 of the grenade body 10 is screwed into an internal thread 52 (Fig. 1), which projects beyond an interior 51 and contains a known ignition chain with pyrotechnic delay. In addition, a peripheral groove 53 and a notch 54 can be seen.

The top view drawn as a sectional illustration FIG. 2 shows the outer shape of the igniter body 4.

Also shown are the twist angle β between the notches 54 and 55 (dashed lines), which characterize the path limitation of the twist of the igniter body 4. One also sees a lateral milling 53a, which is exposed in the secured position according to FIG. 1. In the lower, wide projection of the detonator body 4, a blind hole 45 is made, into which a locking ball 61 projects and delimits a bolt 60 on its displacement path; the steps of reduced diameter are designated 64 to 66 - cf. Fig. 3.

The shape of the split pin 3 and its specific inclusion in the body 4 as well as can also be seen in FIG. 2 the central position of the striker 22 in its secured position. An inner bore 42 is designed as a horizontally lying elongated hole, so that the inner leg 30 with its bent portion 30a can be inserted and passed through in its receiving bore 42.

The longitudinal section of FIG. 3 shows the design of the bolt 60 with its pressure cap 60a and its lower central longitudinal bore 63, in which a return spring 62 is supported against the bottom of the igniter body 4 and holds the bolt 60 in the position shown. It can also be seen that the ignition pin 2 with the slide 70 is displaced from the longitudinal axis A and that this is guided with its lateral guide cam 71 in a groove 47. The firing pin 2 is pushed up by a spring and does not hinder the displacement of the slide 70. The whole is covered at the top by the detonator bracket 20, the bent side edges of which act like a lid.

4 shows i.a. the elliptical curve shape of the groove 47 and a recess 72 in the slide 70 into which a cam 48 protruding in the housing 4 (secured position) engages. The angle of rotation α predetermined by the groove 47 is 90 °.

In contrast to the previous representations, the somewhat simplified FIG. 5 relates to the ignition device 1 in the unlocked state, ie for example shortly after the throw (by hand). The firing pin 2 is centered here on all sides with the longitudinal axis A, is still spaced from the primer 12 and is ready to receive the pulse S required for initiation by the striker 22. It is obvious that the end piece 22 bent at the end touches the detonator bracket 20 and disengages it from the bearing point that the full impact pulse S can act on pin 2. In order to amplify the mechanical pulse S of the hammer 21 and to increase the rigidity of the arrangement, the striker 22 here again has visible side straps 22 '. The inner bore 34 and the outer bore 35, from which the split pin 3 was pulled, can also be seen in the detonator bracket 20.

• 1. Der Splint 3 kann nicht unbeabsichtigt aus dem Zünderkörper 4 herausgezogen werden, da dessen Abkröpfung 30a an der Peripherie des Hohlzylinders 50 ansteht. Siehe Fig. 2; Sicherheitsmechanismus 5.
• 2. Das Auflager 24 des Schlagstücks 22 liegt auf dem oberen Teil des Hohlkörper 50 auf, so dass dieses nicht drehen kann. Siehe Fig. 1; Sicherheitsmechanismus 6.
• 3. Der Zündstift 2 ist im gesicherten Zustand aus der Längsachse A gerückt und kann das Zündhütchen 12 nicht kontaktieren. Siehe Fig. 3; Sicherheitsmechanismus 7.

The functioning of the device described is based on triple security and is as follows:

• 1. The cotter pin 3 cannot be pulled out of the igniter body 4 unintentionally, since its offset 30a is present at the periphery of the hollow cylinder 50. See Fig. 2; Security mechanism 5.
• 2. The support 24 of the striking piece 22 rests on the upper part of the hollow body 50 so that it cannot rotate. See Fig. 1; Security mechanism 6.
• 3. The firing pin 2 has moved out of the longitudinal axis A in the secured state and cannot contact the primer 12. See Fig. 3; Security mechanism 7.

Unlocking / arming the hand grenade:

By finger pressure on the pressure cap 60a of the locking bolt 60, it is disengaged from the position shown in FIG. 3, so that the locking ball 61 now contacts the smallest diameter 64; then the bolt 60 is pressed upwards by the spring 62. Simultaneous manual rotation of the detonator body 4 relative to the hollow cylinder screwed onto the grenade head 11 11, with a force F predetermined by the spiral spring 56 by the angle α = 90 °, causes the unlocking; see. Fig. 4. This shows the bordering / marking 67. This first stage of focusing is easily visually recognizable during the day and palpable at night.

At the same time, the slide 70 in the hollow cylinder 50, along its guides 57, has shifted to the center because the rotation of the guide cams 71 in the groove 47 has shifted along their elliptical curve; see. Fig. 4 in connection with Fig. 5. - The ignition pin 2 is now aligned with the longitudinal axis A. Also, the cut 53a of the hollow body 50 comes to lie in the region of the pin 41 of the striking piece 22, so that a second stage of focusing entry. Under the pressure of the striking spring 23, this can now develop its hammer action as soon as the split pin 3 is pulled out of the bores 42 (in the detonator body), 34 (in the detonator bracket) and 43 (in the detonator body), 35 (in the detonator bracket), as a result of which the detonator bracket 20 - during the throw - is released - this is done by a single manipulation of the thrower: a strong pull on the ring 33.

It can be easily backed up again - for example if the threat situation changes - as long as the cotter pin 3 is not pulled. By pressing the pressure cap 60a a further time, this time into the starting position according to FIG. 3, the device 1 rotates back into the secured position initially described by the spring 56.

A later complete securing, with the split pin 3 pulled, would also be possible, but is subject to similar difficulties as are known from the prior art.

A partial backup according to security levels 2 and 3 is, however, easily possible even without inserting the split pin 3, which means that the hand grenade is already transportable again. This incremental backup is a significant improvement over the known one and corresponds approximately to its full backup in terms of security level.

Claims (12)

1. Fuze for a hand grenade having a pyrotechnically delaying firing chain, having a firing pin which is arranged in a slide and can be moved out of the operating direction, and having a firing hammer which is secured by a fuze bracket and a withdrawable safety pin on a fuze body, with the slide (70) being guided in a fuze body (4), which can be rotated manually, such that it can move at right angles to the longitudinal axis (A) of the fuze (1), with the slide (70) being operatively connected to a peripherally arranged stud (71), with this stud (71) being guided in a groove (47) which is eccentric with respect to the longitudinal axis (A), and with the firing pin (2) being guided, when it is in the safe position, out of the operating area of the firing chain (11, 12) by means of that area of the groove (47) which is furthest away from the longitudinal axis (A).
2. Fuze according to Claim 1, characterized in that a spring (56) acts on the fuze body (4) and rotates with it with respect to the cylinder (50) in the direction of that area of the groove (47) which is furthest away from the longitudinal axis (A).
3. Fuze according to Claim 2, characterized in that the cylinder (50) is a peripherally stepped hollow cylinder, and in that the spring (56) is a spiral spring, which surrounds the hollow cylinder, and in that the outer end of the spiral spring (56) acts on the fuze body (4), and its inner end acts on the hollow elliptical (50).
4. Fuze according to Claim 2, characterized in that the projection of the groove (47) is in the form of an elliptical curve.
5. Fuze according to Claim 1, characterized in that the slide (70) has an extension at the side, to which the stud (71) is fitted.
6. Fuze according to Claim 1, characterized in that the firing pin (2) is loaded in the opposite direction to its operating direction by a spring in the slide (70).
7. Fuze according to Claim 1, characterized in that the firing hammer (21) of the fuze is a striker (22, 22') which is in the form of a two-armed lever and has a support (24) which is provided on its shorter part, and in that, in the safe position, this support (24) blocks the rotary movement of the firing hammer (21).
8. Fuze according to Claims 3 and 7, characterized in that the hollow cylinder (50) has a lateral milled area (53a) which, in the armed position, allows the support (24) to rotate, and thus allows the firing hammer (21) to emit a pulse (S).
9. Fuze according to Claim 8, characterized in that the safety pin (3) is U-shaped and, when it is in the safe position, its additional bend (30a) rests on the hollow cylinder (50) and, when it is in the armed position, can be withdrawn alongside the milled area (53a).
10. Fuze according to Claim 1, characterized in that a locking bolt (60) is provided, which has a resetting spring (62), which is inserted in the locking bolt (60) and its latch positions lock the fuze body (4), or allow it to rotate.
11. Fuze according to Claim 10, characterized in that the bolt (60) has a pressure dome (60a) and has a knurled area/marking (67) on the side, which is concealed in the housing (4) of the fuze (1) when in the safe state.
12. Fuze according to Claim 8, characterized in that the fuze bracket (20) has side lugs, in that the fuze bracket (20) is recessed in a depression in the housing (4) of the fuze (1), such that it is flush with it, when in the safe state, and in that, in the armed position, the end release cam (25) on the inside of the firing piece (22) raises and lifts off the firing bracket (20).