EP1499850A1

EP1499850A1 - Pyrotechnic device with ignition delay

Info

Publication number: EP1499850A1
Application number: EP03749910A
Authority: EP
Inventors: Francesco Ambrico
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-04-29
Filing date: 2003-04-29
Publication date: 2005-01-26
Anticipated expiration: 2023-04-29
Also published as: FR2839146A1; EP1499850B1; CN1650147A; US7634965B2; ES2275109T3; AU2003249387B2; CA2485074C; DE60309690T2; US20060150856A1; AU2003249387A1; FR2839146B1; ATE345485T1; DE60309690D1; CN100535579C; WO2003095934A1; CA2485074A1

Abstract

A pyrotechnic device having an ignition delay between a fuse or igniter and a device to be ignited, including a first element which defines a first space that houses at least one fuse or igniter, and a second element which communicates with a second space that houses the device to be ignited, moreover, the device includes a track containing an evenly burning flammable material, which is in permanent contact with the first space by a connecting portion of the first space and with the second space by an opening. The first element can slide in relation to the second element and/or vice versa such as to alter the length of the track between the connecting portion and the opening, in order to modify the duration of the ignition delay.

Description

PYROTECHNIC DELAY DEVICE

The present invention relates to the field of pyrotechnics. When we want to start a firework, we try to minimize the number of ignitions of individual pyrotechnics, such as rockets, light sources, candles, etc. Thus, the various pyrotechnic pieces, for example rockets placed in mortars, are connected in clusters, that is to say that the quick wick of each piece is connected to another wick directly or via a pyrotechnic delay, itself linked to another wick, to another delay, etc., up to a point to which an electric igniter is connected. It would perhaps be simpler to directly connect each wick of each pyrotechnic part to a specific igniter and, by an electronic circuit to control the instant of ignition of each element. However, in practice, this proves to be far too expensive and it is preferred to use the traditional system with wicks and pyrotechnic delays.

Delay devices are of various types. This will for example be slow bits or Bic ford cords. However, more generally, delays made of powder packed in a cardboard cylinder are used since it is currently the least expensive device. The above delay devices have the disadvantage of not making it possible to achieve any delay time. It is generally accepted that, with standard powders, the length of the cardboard cylinder fixes the duration of the delay which is of the order of one second per centimeter. In practice, it is difficult to obtain relatively precise delays of a duration of less than 2 seconds or greater than 5 to 6 seconds. Otherwise, you have to switch to slow wicks like Bickford cords which are much more expensive. Patent EP 1079200 describes a pyrotechnic device for delay between wicks and / or between igniter and wicks making it possible to select a delay of a determined duration chosen from several predetermined delays.

The present invention provides a pyrotechnic device having the same object as the device of patent EP 1079200 but which is particularly simple and economical to industrialize.

The present invention also provides a pyrotechnic delay device for continuously varying the value of the selected delay over a continuous range.

To achieve these objects, the present invention provides a pyrotechnic device for delaying ignition between a wick or an igniter and a device to ignite comprising a first element defining a first space receiving at least one wick or an igniter; and a second element communicating through an orifice with a second space receiving the device to be ignited, the device comprising a track containing a flammable material regularly burning, produced at the surface of the first and / or the second element, and permanently communicating with the first space by a communicating portion of the first space and with the second space through the orifice, the first element being able to slide with respect to the second element and / or vice versa so as to modify the length of the track between the communicating portion and the orifice to modify the duration of the ignition delay. According to one embodiment of the invention, the second element is a body comprising a recess forming the second space and an opening in which the first element is mounted to move in translation, the first element comprising a chamber forming the first space, the second space communicating with the opening through the orifice.

According to one embodiment of the invention, the recess forming the second space is arranged laterally at the opening, the track consisting of a groove filled with flammable material disposed on the outer wall of the first element, the groove communicating with one end with the chamber through a hole and being placed opposite the orifice.

According to one embodiment of the invention, the recess forming the second space is arranged in the extension of the opening and the track consists of a first groove filled with flammable material placed on the outer wall of the sliding system, the first groove communicating at one end with the chamber through a hole, and a second groove filled with flammable material disposed on the interior wall of the opening and communicating at one end with the second space through the orifice, the first groove being placed opposite the second groove.

According to one embodiment of the invention, inscriptions are made on the external wall of the first element, the body comprising a light opening onto the opening and uncovering part of the inscriptions during the movements of the first element in the opening.

According to one embodiment of the invention, the chamber can also be moved in rotation relative to the element. According to one embodiment of the invention, the first element and the second element are at least partially parallelepipedal and are mounted movable in translation relative to each other, a flat face of the first element being at least partially in vis-à-vis a flat face complementary to the second element, the track consisting of at least one groove rectilinear filled with flammable material arranged on the flat face or the complementary flat face.

According to one embodiment of the invention, the device comprises a carriage, comprising a chamber defining the first space, said carriage being adapted to slide in rails arranged on the wall of a casing containing the second space, the through hole the wall of the casing, the track consisting of at least one groove made on the carriage, containing the flammable material and communicating through a hole with the chamber and connected to the orifice.

According to one embodiment of the invention, the device to be ignited is an enclosure containing a combustion material, and the second element comprises a wall traversed by the orifice and intended to be fixed to the enclosure, the first element being constituted of a carriage, comprising a chamber forming the first space, adapted to slide in rails arranged on the wall on the side opposite to the enclosure, the track consisting of at least one groove made on the carriage, containing the flammable material and communicating through a hole with the chamber and connected to the orifice.

According to one embodiment of the invention, the device to be ignited is an enclosure containing a combustion material, and the second element comprises a fixed plate, traversed by the orifice and intended to be fixed to the enclosure, the first element comprising a movable plate rotatably mounted on the fixed wall on the side opposite the enclosure, the movable plate comprising an opening forming the first space, the track consisting of at least one groove at least partially circular, containing the flammable material, produced on the fixed plate on the side opposite the enclosure, extending through the orifice, and part of which communicates with the opening.

These objects, characteristics and advantages, as well as others of the present invention will be explained in detail in the following description of particular embodiments made without limitation in relation to the appended figures among which: FIG. 1 represents a sectional view of a first embodiment of the present invention; 2 shows a view of the device of Figure 1 in the direction A; Figure 3 shows a view of the device of Figure 1 in direction B; Figure 4 shows a particular element of the device of Figure 1; 5 shows a variant of the element of Figure 4; FIG. 6 represents a variant of the device according to the first embodiment; FIG. 7 represents a variant of the device according to the first embodiment; Figure 8 shows a sectional view of a second embodiment of the device according to the present invention; FIG. 9 represents a perspective view of a third embodiment of the device according to the present invention; Figures 10 and 11 show sectional views of the device of Figure 9; Figure 12 shows a sectional view of a fourth embodiment of the device according to the present invention; Figure 13 shows a section of Figure 12 along lines XIII-XIII; FIG. 14 represents a perspective view of a fifth embodiment of the device according to the present invention; Figure 15 shows a view of a part of the device of Figure 14 in direction C; and FIG. 16 represents a view of another part of the device of FIG. 14 in the direction D. Figures 1 to 3 show views of a first embodiment of a delay device 10 according to the present invention. FIG. 4 represents more precisely a particular element of the first embodiment of the device 10 according to the invention.

The device 10 consists of a guide 12 traversed by a cylindrical opening 14 in which a sliding system 16 cylindrical can slide. Preferably, the sliding system 16 and the guide 12 can be molded parts made of plastic material, or machined parts made of metallic material, or can combine metallic materials and plastic materials. The outside diameter of the sliding system 16 corresponds substantially to the inside diameter of the opening 14. The sliding system 16 comprises at one end a cylindrical chamber 18 whose internal walls 19 are coated with a highly flammable material, preferably a material s' igniting very easily inside a room. This material is for example black powder bonded. Chamber 18 is intended to receive the end of one or more wicks (not shown) or one or more igniters.

The guide 12 also comprises a cylindrical chamber 20 with an axis parallel to the axis of the opening 14 and disposed laterally at the opening 14 at one end of the latter. The chamber 20 communicates with the opening 14 through a cylindrical orifice 22. The internal walls 23 of the chamber 20 are coated with a highly flammable material similar to the internal walls 19 of the chamber 18. The chamber 20 is intended to receive the end of one or more wicks (not shown).

Means (not shown) for holding the wicks or igniters are disposed at the level of the chambers 18, 20. Such means consist for example of pierced caps. The wall of the sliding system 16 at the level of the chamber 18 can also be flexible enough to be deformed by a tool so as to block the wick (s).

A combustion track is produced on the sliding system 16 and consists of a rectangular groove 24 filled with a flammable material and extends along the outer wall 25 of the sliding system 16 cylindrical substantially along a generatrix. The groove 24 opens at one end 26 into the chamber 18 and extends to the opposite end of the sliding system 16. The flammable material allows, when ignited at one end of the groove 24, to propagate a flame towards The other end of the groove 24 at a substantially constant speed. It will be, for example, packed black powder or a specific cord such as a fine slow wick manufactured by the company Bickford. Openings (not shown) are provided, for example at the level of the guide 12, to allow the evacuation of the gases resulting from the combustion of the flammable material placed in the groove 24.

A rectangular guide groove 27 extends along the outer wall 25 of the sliding system 16 cylindrical substantially along a generatrix. The guide groove 27 is disposed substantially diametrically opposite the combustion track relative to the axis of the sliding system 16. The guide groove 27 is intended to receive the end of a guide screw (not shown) screwed into a threaded hole 28 of the guide 12.

When the sliding system 16 is pressed into the opening 14, the guide groove 27 cooperates with the guide screw so that the combustion track is opposite the orifice 22. Depending on the depression of the system sliding 16 in the opening 14, the length of the combustion track separating the end 26 from the orifice 22 varies.

When the wick arranged in the chamber 18 is lit, or when the igniter arranged in the chamber 18 is actuated, a flame is propagated inside the chamber 18 and causes the powder disposed extremely extremely to ignite on the internal walls 19 of the chamber 18. The flame thus produced propagates to the end 26 of the groove 24 communicating with the chamber 18 and ignites the flammable material at the end 26 of the combustion track. The combustion of the material propagates along the combustion track until the flame reaches the orifice 22. The powder which coats the internal walls 23 of the chamber 20 ignites, causing the wick to ignite or wicks arranged in the chamber 20. The rate of propagation of the combustion of the flammable material in the groove 24 being substantially constant, the time taken for the flame to reach the orifice 22 varies according to the depression of the sliding system 16 in 1 opening 14. This duration corresponds substantially to the duration between the ignition of the wick arranged in the chamber 18 and the ignition of the wick arranged in the chamber 20. Consequently, the more the sliding system 16 is pressed into the opening 14, the lower the delay.

FIG. 5 represents a variant of the first embodiment of the device 10 according to the invention in which the combustion track consists of a groove 30 extending in a helicoid on the outer wall 25 of the sliding system 16 from the end 26 where the groove 30 opens into the chamber 18 to the opposite end of the sliding system 16. A helical track having a greater length than a straight track, the device 10 according to the present variant allows the selection of delays to the ignition higher than the device 10 of FIG. 1.

According to the present variant, the sliding system 16 may comprise a helical guide groove (not shown) interleaved with the groove 30 and which, as explained above, cooperates with the end of a guide screw. Such a form of guide groove ensures adequate positioning of the combustion track relative to the orifice 22. FIG. 6 represents another variant of the first embodiment. According to this variant, the sliding system 16 comprises a lug 32 which extends substantially radially with respect to the outer wall 25. The guide 12 comprises a groove (not visible in FIG. 6) in which the lug 32 can slide. cooperation of the lug 32 and the groove makes it possible to guide the sliding system 16 when it is inserted into the guide 12. In addition, the lug 32 is accessible by an operator, and allows easy handling of the sliding system 16 during its insertion into the guide 12.

According to this variant, the guide 12 includes a light

34 leading to the opening 14 and which reveals the outer wall 25 of the sliding system 16 when the latter is placed in the opening 34. It is then possible to make inscriptions 35 on the outer wall 25 of the sliding system 16 which are visible to the operator through the opening 34. The inscriptions 35 may represent the duration of the delay obtained with the device 10 as a function of the depression of the sliding system 16 in the opening 14. For example, inscriptions 35 in Arabic numerals can indicate a delay in seconds, and inscriptions in the form of parallel lines can indicate a delay in tenths of a second.

According to another variant of the device 10 according to the invention, the external wall 25 of the sliding system 16 comprises notches (not shown) coming to cooperate with a notch (not shown) arranged on the internal wall of the opening 14. The notches allow to precisely control the insertion of the sliding system 16 into the opening 14, and also make it possible to maintain the sliding system 16 in position in the opening 14 once the adjustment in position has been carried out.

According to another variant of the invention, the orifice 22 extends substantially over an arc of a circle so as to ensure that the combustion track faces the orifice 22 despite a possible imprecision during the installation of the sliding system 16 in the opening 14.

According to another variant of the invention, the sliding system 16 has a non-cylindrical section, for example square or triangular, capable of sliding in an opening of complementary shape to the guide 12. Such a shape makes it possible to guide the sliding system 16 in one opening 14 and the positioning of the groove 24 relative to the orifice 22 without requiring any particular guide means. According to another variant of the invention, the sliding system 16 is extended at one of its ends by a gripping means which remains accessible to an operator whatever the insertion of the sliding system 16 into the opening 14 so to allow easy handling of the sliding system 16. Figure 7 shows another variant of the first embodiment. According to this variant, the second chamber 20 of the guide 12 is arranged substantially in the central part of the opening 14, laterally to the latter. The sliding system 16 comprises a lug 32 capable of sliding in a slot 36 extending along a generatrix of the guide 12. The axial length of the sliding system 16 is substantially equal to half the axial length of the opening 14. The operation of the device according to this variant is identical to what has been previously described. The main advantage of this variant is that the flammable material placed in the groove 24 of the sliding system 16 remains protected by the guide 12 whatever the position of the sliding system 16 in the guide 12.

FIG. 8 represents a second embodiment of the invention in which the device 40 comprises a sliding system 42 similar to that of the first embodiment. The sliding system 42, which is substantially cylindrical, comprises at one end a chamber 44 communicating, through an orifice 45, with a groove 46 extending on the external wall of the sliding system 42 according to a generator. Room 44 receives the end of one or more wicks or one or more igniters.

The device 40 also includes a cylindrical guide 47 partially crossed by a cylindrical opening 48 in which the sliding system 42 can be moved. The guide 47 comprises a chamber 50, for example cylindrical, extending the opening 48 and separated from it by a wall 51. The guide 47 also includes a groove 52 produced at the level of the internal wall of the opening 48, extending along a generatrix portion of the opening 48, and opening into the chamber 50 through an orifice 53. The internal walls of the chambers 44, 50 are covered with a highly flammable material.

The two grooves 46, 52 are filled with a flammable material similar to the material filling the groove 24 for the first embodiment. The sliding system 42 is introduced into the opening 48 of the guide 47 so that the groove 46 covers part of the groove 52 according to the depression of the sliding system 42 in the guide 47. When igniting the wick or when 'the igniter placed in the chamber 44 is actuated, the flammable material filling the groove 46 is ignited at the orifice 45. The flame then propagates slowly and regularly in the groove 46. When the flame reaches the area where the groove 46 begins to overlap groove 52, the flammable material filling groove 52 ignites at the end 54 of groove 52. The flame then propagates in groove 52 until it reaches chamber 50 to ignite the second wick . Therefore, depending on the depression of the sliding system 42 in the opening 48, the material located

1 end 54 of the groove 52 is ignited more or less quickly. This controls the delay provided by the device 40.

Figures 9, 10 and 11 show a third embodiment of the invention in which the device 55 is produced directly on a casing 56 delimiting an interior chamber 57 containing the hunting of a rocket, a light fountain, etc. The housing 56 is for example cylindrical. A carriage 58 slides in two rails 59 arranged on the outer wall 60 of the casing 56 substantially along radii. A cylindrical chamber 61 projecting from the carriage 58 receives the end of a wick or an igniter.

Figures 10 and 11 show a section of the device 55 at the level of the chamber 61 respectively along a plane perpendicular to the axis of the casing 56 and a plane containing said axis. The chamber 61 communicates through an orifice 62 with one end of a groove 63 made in the carriage 58. A flammable material with regular combustion is placed in the groove 63. Openings (not shown) are provided, for example at the level of the carriage 58, to allow the evacuation of the gases resulting from the combustion of the flammable material placed in the groove 63.

The housing 56 includes an orifice 64 communicating the groove 63 of the carriage 58 with the chamber 57 containing the flush. The housing 56 consists, at least in the vicinity of the groove 63, of a thermally insulating material. When the wick arranged in the chamber 61 is ignited or when the igniter is actuated, the flammable material is ignited at the end of the groove 63. The flame propagates along the groove 63 until it reaches the orifice 64 to ignite the chase. By moving the carriage 58 along the rails 59, the length of the combustion track separating the end of the groove 53 opening into the chamber 61 from the orifice 64 is varied. This modifies the ignition delay of the hunt.

Devices 55 according to the third embodiment can equip a set of rockets and be connected to the same ignition wick. The devices 55 then make it possible, from a single ignition wick, to ignite with different delays each rocket of the set of rockets. According to a variant of the third embodiment, the cylindrical chamber 61 extends substantially tangentially to the casing 56 and is extended by the groove 63. This makes it possible to limit the radial size of the device according to the invention. According to a variant of the third embodiment, an auxiliary groove (not shown) communicating with the orifice 64 is produced on the outer wall 60 of the casing 56 and filled with a flammable material similar to the material filling the groove 63. The auxiliary groove is arranged on the housing 56 so that the groove 53 covers a more or less significant part of the auxiliary groove according to the sliding of the carriage 58 relative to the housing 56. When igniting the flammable material in the groove 63 at the orifice 62, the flame propagates regularly in the groove 63 until it reaches the auxiliary groove. The flame then propagates in the auxiliary groove up to orifice 64 to ignite the flush.

According to a variant of the third embodiment, the casing 56 consists of a plate intended to be fixed, for example by gluing, on an enclosure containing the hunting of a rocket, the rest of the device 55 being unchanged. The shape of the casing 56 is then adapted to the enclosure on which it will be fixed. A hole is made in the enclosure, before fixing of the device 55, which communicates with the orifice 64, once the casing 56 is installed. This variant makes it possible to equip conventional rockets with the delay device 55 according to the invention while modifying the rocket as little as possible. In the case where the material constituting the enclosure is sufficiently conductive, it may not be necessary to pierce the enclosure. In fact, the casing 56 then consists of a thermal insulator so that when the flame reaches the orifice 64 which uncovers part of the enclosure, the heat produced is sufficient enough to ignite the charge through the enclosure. .

Figures 12 and 13 show a fourth embodiment of the invention. The device 70 comprises a rail of guide 71 having the form of a substantially parallelepiped bar on which a first drill bit can be fixed by means of a movable hook 72. An orifice 73 passes through the guide rail 71 at the level where the first drill bit is fixed to the rail guide 71. The guide rail 71 is extended on its two longitudinal edges by two folded flanks 74 which guide in translation a sliding body 75 having the shape of a substantially parallelepiped bar. A second wick can be fixed to the sliding body 75 on the side of the face opposite the rail 71 by means of a movable hook 76. A groove 78 is formed on the face of the sliding body 75 opposite the rail 71. The groove 78 is, for example, rectilinear and of square section. An orifice 80 passes through the sliding body 75 at the level where the second wick is fixed to the sliding body 75 and opens, on the opposite face, into the groove 78. When the sliding body 75 is guided in translation by the folded sides 74, the orifice 77 crossing the guide rail 71 opens permanently at the groove 78. The regions of the guide rail 71 and of the sliding body 75 intended to be in contact with the wicks, and the orifices 73, 80, are covered with flammable material. The groove 78 is filled with a flammable material similar to the material filling the groove 24 for the first embodiment. Openings are provided at the level of the guide rail 71 or of the sliding body 75 to allow the evacuation of gases resulting from the combustion of the flammable material disposed in the groove 78. The guide rail 71 has a greater length than the sliding body 75 so as to completely cover the groove, and protect the flammable material which it contains, whatever the position of the sliding body 75 relative to the guide rail 71.

When igniting, for example, the first wick fixed at the level of the guide rail 71, the flame propagates very quickly to the groove 78 through the orifice 73. The flame then propagates slowly and regularly in the groove 78 until reaching port 80 and igniting the second wick. As a result, depending on the relative position between the sliding body 75 and the guide rail 71, the portion of the groove 78 placed between the orifices 73, 80 is modified and the delay provided by the device 70 is thus controlled.

The fourth embodiment has the advantage of being of particularly simple design and of having a reduced bulk.

According to a variant of the fourth embodiment, the groove 78 is produced in whole or in part on the guide rail 71.

FIGS. 14 to 16 represent a fifth embodiment of the invention similar to the third embodiment of the invention in which the device 81 is produced directly on a casing 56 delimiting an interior chamber 57 containing the hunting of a rocket, a light fountain, etc. The housing 56 is for example cylindrical. The device 81 comprises an intermediate piece 82, cylindrical, fitted on the casing 56, and covering an open end of the casing 56. The intermediate part 82 is fixed relative to the casing 56 and is sandwiched between the casing 56 and a cylindrical base 84. The cylindrical base 84 is coaxial and is rotatably mounted relative to the intermediate piece 82.

FIG. 15 represents a view in the direction C of the adjusting piece 82. The adjusting piece 82 comprises a circular groove 85, for example of square section, which extends on the face of the adjusting piece 82 opposite the casing 56. The groove 85 follows a circle but does not close on itself. One end of the groove 85 is extended by an orifice 86 which passes through the adjustment piece 82 to open into the interior chamber 57 of the casing 56. A flammable material with regular combustion is placed in the groove 85 and the orifice 86. The part intermediate 82 includes a threaded hole 87. FIG. 16 represents a view in the direction D of the base 84. The base 84 comprises an opening 88 produced on the face of the base 84 in contact with the intermediate piece 82 and which extends substantially along a radius of the base 84 from the side edge towards the center. The opening 88 receives a wick or an igniter (not shown). The interior of the opening 88 is covered with a flammable material. The base 84 comprises a threaded hole 89 coaxial with the threaded hole 87 of the intermediate piece 82. A screw (not shown) cooperates with the threaded holes 87, 89 and ensures the rotary mounting of the base 84 relative to the intermediate piece 82. When the base 84 is mounted on the intermediate piece 82, the opening 88 of the base 84 communicates with the circular groove 85 of the intermediate piece 82. The intermediate piece 82 has inscriptions 89 on the lateral edge which indicate the duration of the delay provided by the device 81. The delay to be taken into account is that indicated by the inscription located at the opening 88. Openings (not shown), for example at the base 84 or the intermediate part 82, are provided to allow the evacuation of the combustion gases of the flammable material placed in the groove 85.

When the wick is ignited or the igniter is actuated in the opening 88 of the base 84, the flame propagates very quickly to the groove 85. The flame then propagates slowly and regularly in the groove 85 until 'to reach the orifice 86 and ignite the contents of the interior chamber 57.

By rotating the base 84 relative to the intermediate piece 82, the portion of the circular groove 85 placed between the opening 88 and the orifice 86 is modified and the delay provided by the device 81 is thus controlled.

According to a variant of the fifth embodiment, the groove 85 can be partly or entirely produced on the base 84. The device according to the fifth embodiment of the invention has the advantage of requiring few modifications to the casing on which it is mounted since it replaces the bottom of the casing. The device according to the present invention has many advantages:

First, it provides an adjustable ignition delay.

Secondly, the ignition delay can be modified continuously since the combustion track, produced on the surface of one or more parts of the device, permanently communicates with the regions where the wicks, igniters or the material are arranged. to ignite whatever the relative positions between the parts constituting the device.

Thirdly, the combustion track being produced on the surface of one or more parts of the device, the gases resulting from the combustion of the material disposed in the combustion track can easily be removed, thus ensuring uniform combustion of the flammable material.

Of course, the present invention is susceptible of various variants and modifications which will appear to one skilled in the art. In particular, the guide 12 may include several chambers 20, each chamber comprising one or more wicks. The sliding system 16 can then comprise several combustion tracks, each track being able to be arranged opposite an orifice communicating with one of the chambers so as to ignite several wicks with different delays. In addition, some of the variants described above can be combined, in particular with the second embodiment. For example, inscriptions can be made on the outer wall of the sliding system 42 of the device 40 according to the second embodiment of the invention to indicate the delay provided by the device 40 as a function of the depression of the sliding system 42 in the guide 47.

Claims

1. Pyrotechnic device (10, 40, 55, 70, 81) for delaying the ignition between a wick or an igniter and a device to be ignited comprising:

- a first element (18, 44, 61, 71, 84) defining a first space (18, 44, 61, 88) receiving at least one wick or an igniter; and

- a second element (12, 47, 56, 75, 82) communicating through an orifice (22, 53, 64, 80, 86) with a second space (20, 50, 57) receiving the device to be ignited, characterized in that that it includes a track (24, 30, 46,

52, 63, 78, 85) containing a regularly burning flammable material, produced at the surface of the first and / or second element (16, 42, 47, 58, 75, 82), and permanently communicating with the first space by a communicating portion (22, 53, 64, 73) of the first space and with the second space through the orifice, the first element being able to slide relative to the second element and / or vice versa so as to modify the length of the track between the communicating portion and the orifice to modify the duration of the ignition delay. 2. Device (10, 40) according to claim 1, in which the second element (12, 47) is a body comprising a recess, forming the second space (20, 50), and an opening (14, 48) in which is mounted movable in translation the first element (16, 42), said first element comprising a chamber forming the first space (18, 44, 61, 88), the second space communicating with the opening through the orifice (22, 53 ).

3. Device (10) according to claim 2, in which the recess forming the second space (20) is arranged laterally at the opening (14), and in which the track consists of a groove (24, 30) filled with flammable material disposed on the outer wall (25) of the first element (16), the groove communicating at one end with the chamber (18) through a hole (26) and being placed opposite the orifice (22).

4. Device (40) according to claim 2, in which the recess forming the second space (50) is arranged in the extension of the opening (48), and in which the track consists of a first groove (45 ) filled with flammable material disposed on the outer wall of the sliding system (42), the first groove communicating at one end with the chamber (44) through a hole (45), and a second groove (52) filled with flammable material disposed on the inner wall of the opening (48) and communicating at one end with the second space through the orifice (53), the first groove being placed opposite the second groove.

5. Device (10, 40) according to claim 2, in which inscriptions (35) are produced on the external wall (25) of the first element (16), the body (12) comprising a lumen (34) opening onto the opening (14) and discovering part of the inscriptions during the movements of the first element in the opening.

6. Device (10, 40) according to claim 2, wherein the chamber (18, 44) can be further rotated relative to the element (12, 47).

7. Device (70) according to claim 1, wherein the first element (71) and the second element (75) are at least partly parallelepiped and are mounted movable in translation relative to each other, one side plane of the first element being at least partially opposite a plane face complementary to the second element, the track consisting of at least one rectilinear groove (78) filled with flammable material arranged on the plane face or the face complementary plane.

8. Device (55) according to claim 1, comprising a carriage (58), comprising a chamber (61) defining the first space, said carriage being adapted to slide in rails (59) arranged on the wall of a casing ( 56) containing the second space

(57), the orifice (64) passing through the wall of the casing, the track consisting of at least one groove (63) produced on the carriage, containing the flammable material and communicating through a hole (62) with the chamber and connected to the orifice.

9. Device (55) according to claim 1, in which the device to be ignited is an enclosure containing a combustion material, and in which the second element (56) comprises a wall traversed by the orifice and intended to be fixed on the enclosure, the first element consisting of a carriage (58), comprising a chamber (61) forming the first space, adapted to slide in rails (59) arranged on the wall on the side opposite to the enclosure, the track consisting of at least one groove (63) made on the carriage, containing the flammable material and communicating through a hole (62) with the chamber and connected to one orifice.

10. Device (81) according to claim 1, in which the device to be ignited is an enclosure (56) containing a combustion material, and in which the second element comprises a fixed plate (52), crossed by the orifice (86 ) and intended to be fixed on the enclosure, the first element comprising a movable plate (84) rotatably mounted on the fixed wall on the side opposite to the enclosure, the movable plate comprising an opening (88) forming the first space, the track consisting of at least one groove (85) at least partially circular, containing the flammable material, produced on the fixed plate on the side opposite the enclosure, extending through the orifice, and part of which communicates with 1 'opening.