WO2012168200A1 - Device and method for the thermal compensation of a weapon barrel - Google Patents

Abstract

The invention relates to a device and a method for the thermal compensation of a weapon barrel of a gun (10) comprising at least one weapon barrel (11) that is mounted in a cradle (3) and in a barrel support (4) as an extension of the cradle (3). Multiple temperature sensors (p1-p16) are integrated in the cradle (3) and the barrel support (4). The sensors are connected to a data box (7) via data lines (6), and the data box (7) is connected to a data processing device (9). The data processing device (9) can act on actuators of the gun (10). The temperature of the cradle (3) and the barrel support (4) is measured by means of the temperature sensors (p1-p16). Then, the temperature differences between the upper and lower sides and the right and left sides of the cradle (3) and of the barrel support (4) are ascertained. The barrel inclination is calculated from said values, and then a compensation for the barrel inclination is carried out by adjusting the alignment of the weapon barrel (11) in azimuth and/or elevation.

Description

 DESCRIPTION

Apparatus and method for thermal compensation of a weapon barrel

The invention relates to a gun barrel of a weapon, such as a revolver gun for use in land- or sea-based air defense. In particular, this invention relates to a gun barrel stored in a cradle and a pipe support, wherein the pipe cradle for stabilization, guidance and vibration damping is continued in a pipe support, which supports the pipe at several points or supports.

 A gun usually includes a lower mount, a tower and a pipe cradle with pipe support in which the pipe is mounted (EP 1 154 219 A). When exposed to the sun, the upper side of the cradle is exposed to a greater increase in temperature, whereas the non-exposed to the sun's lower side experiences only a smaller increase in temperature. The resulting thermal difference results in a differential thermal expansion between the upper and lower sides of the tube cradle, as a result of which a tube of a certain length I deflects downwardly at a certain angle δ at its free end from the original tube axis. This deflection depends strongly on the environmental and weather influences and in turn significantly affects the hit probability of the weapon.

 Such thermal differences can also occur laterally - for example when the weapon experiences solar radiation primarily from the side at sunrise or sunset, or also from wind, which cools the windward gun side more than the side facing the wind. During a real use, such effects will occur in combination.

At each shot, the tube is stressed by the explosive gases and at the same time frictional heat is generated by the mechanical friction between the tube and the projectile. This leads to an increase in temperature of the tube. This is especially the case when the weapon is used in the serial fire. Then the heat is concentrated at the closure end of the gun and on the tube top - where the heat is transferred by convection. This shot-related temperature gradient also leads to a deflection of the free rendes out of the desired position out.

 Simple passive solutions use according to the teaching of DE 30 05 1 17 a directly attached to the pipe protective cover, wherein the protective cover is not designed radially symmetrical according to the further teaching of DE 199 04 417 to counteract asymmetric heating.

 DE 1918 422 discloses a heat protection cover of a metal shell surrounding the gun pipe at a small distance, wherein acts as a thermal insulation, the quiescent air layer between the gun barrel and the metal shell. These solutions are static and can not respond to changing environmental conditions.

 According to the teaching of WO 97/47939 or US Pat. No. 4,753,154, double-walled gun casings guide a working fluid between the two casing surfaces in order to improve the heat removal from the shot. These systems also operate unregulated and purely passive.

Active heating elements applied directly to the gun barrel are disclosed in DE 32 19 124 and GB 2,328,498. The heating strips parallel to the tube axis overcompensate for external temperature effects by heating the tube to a temperature that is about 10 ° C above the mean ambient temperature. The deflection of the tube from the standard position is determined for example by optical methods. Thus, this method is very energy-consuming and at the same time very sluggish, the optical methods are susceptible to the mechanical system load during firing.

 The shot-related temperature increase measures according to DE 44 33 627 a thermocouple, which is introduced into the wall of the cargo space by blind hole. On the one hand, the mechanical stability is impaired by the bore, on the other hand, no temperature gradient can be absorbed over the pipe length.

 Japanese Abstract JP 7-91891 discloses an active measurement of tube deflection by means of optical systems and at the same time a compensation of the tube bending over a hydraulic cylinder acting on both ends of the weapon tube. This process is very complicated. In addition, compensation can only take place in the plane formed by the tube axis and the center axis of the hydraulic cylinder. Therefore, no general compensation in azimuth and elevation is possible.

 It is an object of the invention to provide an apparatus and a method by means of which a simple and very cost-effective compensation of a thermally induced Rohrverbiegung is also possible during firing.

The problem is solved by the features of claim 1 with regard to the device and claim 6 in terms of the method. Advantageous embodiments are shown in the subclaims. As you know, the gun barrel tilts down when exposed to sunlight. This deformation is caused by temperature differences between the upper and lower sides of the pipe support and the cradle. - The effect of the pipe support and the effect of the cradle can basically be regarded as separate problems; should be superpositioned to determine the total pipe inclination.

 The invention is therefore based on the idea to use temperature sensors and thus to provide a system for temperature correlation. The system is technically capable of determining the temperature differences between the upper and lower sides of the pipe support (the opposite sensors) and between the right and left side of the pipe support (the opposite sensors). The calculation of the pipe inclination is carried out by means of the temperature differences. The compensation of the pipe inclination then takes place via the inclination value, whereby the compensation takes place by changing the orientation of the pipe in azimuth and / or elevation. At the same time a monitoring of the temperature sensors and the Databox can be integrated.

 The temperature compensation function is used as an additional parameter in the weapon control and in particular in the calculation of azimuth and elevation of the weapon. Thus, a temperature-induced pipe deflection can be compensated directly by the servomotors of the weapon. Thus, the inventive method is very fast; It regulates with the usual speed of up to several 10 ° per second.

 At the same time, the method can be used during the shooting. It is not necessary to move the weapon from the ready to fire state to a non-ready for service condition to perform the tube compensation. This increases the service life of the weapon.

 For the inventive device only a few technical modifications are made. Essentially, the installation of known temperature sensors and their connection to the Databox are sufficient on the hardware side. Thus, the device is very inexpensive.

 The pipe compensation does not induce new bending moments or stresses in the pipe. This increases the life of the weapon.

 The failure of individual sensors can be compensated by a mathematical model, since a steady temperature distribution in the pipe cradle and pipe support can be assumed (plausibility check). However, the evaluation algorithm contains various fallback levels in the event that several sensors fail. Thus, the system is particularly stable against the failure of individual sensor data.

In continuation of the invention, the time course of the temperature correlation function recorded and stored for later maintenance work in the gun computer readable. As a result, the thermal load of the gun can be logged afterwards or errors in the calculation algorithm can be detected.

 According to the usual military temperature ranges, the sensors and the Databox are designed for a functional operation, usually from -46 ° C to + 120 ° C. In this temperature range, the measurements are made with a sufficiently high resolution and accuracy. Resolution and accuracy result from the mathematical model used, a resolution of 0.1 ° C and an accuracy of 0.2 ° C have proven to be sufficient in practice.

 The present idea is thus characterized by:

 • very simple measuring method with conventional temperature sensors; The system is inexpensive and stable

 • Redundancies in the sensors with high reliability of the system against the failure of individual sensors

 • Very fast compensation of pipe deformation via gun drives

 • Use during shooting possible, even with serial fire

 • Compensation of azimuth errors as well as elevation errors due to thermally induced tube deformation

 • no mechanical impairment of the pipe or the pipe support by measuring equipment.

Reference to an embodiment with drawing, the invention will be explained in more detail. It shows:

1 shows a turret according to the prior art,

 2 shows the gun trough with the device according to the invention in the cradle and the pipe support,

3 is a simplified representation of the arrangement of the sensors of Fig. 2,

4 is a block diagram of the method.

1 shows a conventional turret guard 10 with a turret 1, a lower mount 2, a cradle 3 and as an extension of the cradle 3 a pipe support 4. The pipe support 4 consists essentially of a lattice frame (not shown) and, like the entire Protected 10 with a protective cover (not shown in detail) be disguised. According to Fig. 2, such a gun 10 with a plurality of temperature sensors p1 - pn, preferably a number of 16, in the region of the pipe cradle 3 and pipe support 4 is provided. By means of the 16 sensors (p1 -p16) the temperature is measured for the pipe support 4 (twelve sensors) and for the weighing walls 3 (four sensors). Connector boxes 5 summarize the signals of the temperature sensors p1 -p16 from pipe support 4 and cradle 3 and transmit them via data connections 6 to the data box 7, in which the analog signals of the temperature sensors are digitized. Subsequently, the data box 7 sends the data via the Ethernet link 8 to the GCU 9 (DVS). The GCU then compensates for the deformation by means of an offset to the horizon (inclination value adjustment). The Databox 7 includes an analog / digital converter and a server with Ethernet.

 The arrangement of the sensors in pipe cradle and pipe support and the connection of the components will be described below. Starting from FIG. 3, four planes are defined substantially perpendicular to the tube axis, wherein one plane E4 preferably lies in the tube cradle and three planes E1-E3 preferably in the tube support. The planes each carry four temperature sensors (e.g., PT 100) generally known in the art, which are preferably located at the corners of the planes. The first plane E1 near the mouth of the muzzle carries the four sensors p1 -p4, the next level in the direction of the cradle E2 carries the sensors p5-p8, etc. The sensors are connected to the data box 7 via data lines 6. The Databox 7 digitizes the analog signals of the temperature sensors and sends the temperature data via a Datalink 8 to the GCU 9. With this arrangement, it is possible to measure the temperature distribution at pipe cradle 3 and pipe support 4.

 The values of the temperature sensors p1-p16 are digitized and transmitted to the data processing device (GCU 9). At the same time they are compared with the respective storage values of the tube 1 1. For the temperature-induced tube deflection, a mathematical model has been developed, which uses optimization parameters to establish the relationship between the temperature values of the probes p1 -p16 and the total tube deflection.

The sequence of the method according to the invention is summarized in FIG. 4. It will be apparent to those skilled in the art from the general algorithm presented herein without further effort how the compensation of the azimuth error or a hybrid form of these two would have to be configured, so that an explicit statement can be dispensed with here. The invention relates equally to the compensation of the azimuth error. The numerical weight parameters a, b, g are either entered in advance into the system (GCU) or determined during the measurement and setting up of the gun 10 and incorporated into the mathematical model. The temperature values are polynomized to give a length consideration for mapping the tube error. The GCU 9 receives from the Databox 7 temperature values T, each with an index for the sensor in question. Thus, averaged temperature differences in elevation of each sensor level E1 to E4 of the pipe support and the cradle are determined. In parallel, it will be determined if and how many of the sensors are functional and deliver plausible values.

 From

r (\ T El _oben_ right + T El _oben _links}) (\ T El_unten_ right + T El _unten _ left /) _r0

¹ EX_Diff _El

El _ Number _ _ _obere correct sensors ^~ T _ El Anza ^"hl _ correct ^_unt" ere _ Se ^{"nsoren 1 J}

to

 (\ T EA _ top _ right + T EA _ top _ left}) (\ T E A _unten_ right + T EA _unten_ left})

 EA Diff El = = =

 EA _ number _ correct _ upper _ sensors EA _ number _ correct _untere _ sensors ° QJ result in the temperature differences in the planes E1 to E4. The pipe pitch V for each sensor plane results from the application of the following correlation, where a and b are numerical adjustment parameters. It follows:

from

 V 'Ei Tube _P El = a R El - T E \ Diff El + h R El

to

 V 'E3 Tube _P El = a R El - T E3 Diff El + h R El

and

 EA Tube _P El W El EA diff El W El

Subsequently, the determined total pipe pitch is weighted for each sensor plane E1 - E4. This simplifies the plausibility check and ensures the modularity for calculating the total pipe pitch (if one sensor level fails). It follows:

VR, ear RP El V El Pipe P El ^' Sl El ^~ * ^~ ^ El Pipe P El ^' & 2 El + ^T V 'E3 Pipe P El g 3 El [wheel] and

V Pipe WP El ^ EA Pipe P El ^' S 4 El [rad] with the weighting parameters g to be adjusted numerically. In a further embodiment, the inherent inertia of the system is additionally taken into account. This is due to the fact that the sensors p1 -p16 can display much faster temperature changes than this gradient in pipe 1 1 and pipe support 4 or pipe cradle 3 can compensate. To take account of the time delay, a so-called D component is added to the control. This is composed of the first numerical derivative of the aforementioned P-shares of the pipe support 4 and the cradle. 3

This is multiplied by the D parameters.

v _ KV 'pipe _R _ P El "

'Tube RD El ^~ 7 ^~ R El

 - [rad]

and

 AV R, ear W P El

 Tube W D El ■ D W El

 At [rad] where the D parameters are again numeric fit parameters. The total pipe inclination is determined by the sum of the P components and the D components of the pipe support and the cradle.

VR, ear El pipe RP El + ^ V 'pipe P El + ^ V' pipe RD El + ^T V 'pipe WD El [rad]

Claims

1 . Device for thermal compensation of a weapon barrel (1 1) of a gun (10) with at least one weapon barrel (1 1), which is mounted in a pipe cradle (3) and as an extension of the cradle (3) in a pipe support (4), characterized that a plurality of temperature sensors (p1 -p16) are connected to the cradle (3) and the pipe support (4), which are connected via data lines (6) to a data box (7) and the data box (7) to a data processing device (9), wherein the data processing device (9) calculates a pipe inclination by means of temperature differences and for thermal compensation on actuators for changing the orientation of the gun barrel (1 1) can act. 2. Apparatus according to claim 1, characterized in that preferably 16 temperature sensors (p1-p16) are involved, wherein variations in the number are possible. 3. Apparatus according to claim 1 or 2, characterized in that substantially perpendicular to the tube axis preferably four levels (e1 -E4) are defined, wherein preferably a plane (E4) in the tube cradle (3) and preferably three levels (E1 -E3 ) lie in the pipe support (4). 4. Apparatus according to claim 3, characterized in that the temperature sensors (p1-p16) are preferably arranged in the region of the corners of the planes (E1 -E4). 5. Device according to one of claims 1 to 4, characterized in that the pipe support (4) is like a frame. 6. Device according to one of claims 1 to 5, characterized in that the actuators are schützeigene servo motors, with which the weapon barrel (1) in azimuth and / or elevation can be aligned. 7. A method for thermal compensation of a weapon barrel (1 1) of a protected (10) with at least one weapon barrel (1 1), which is mounted in a pipe cradle (3) and as an extension of the pipe cradle (3) in a pipe support (4) with the steps: • measuring the temperature by means of temperature sensors (p1 -p16) on the cradle (3) and the pipe support (4), Determining the temperature difference between the upper and lower side and the right and left sides of the cradle (3) and the pipe support (4),  • calculation of the pipe inclination by means of the determined temperature differences, • Compensating the pipe pitch by changing the alignment of the gun barrel (1 1). 8. The method according to claim 7, characterized in that temperature differences of each sensor plane (E1 to E4) of the pipe support (4) and the pipe cradle (3) are determined in elevation and / or azimuth. 9. The method according to claim 7 or 8, characterized in that the temperature-induced pipe deflection can be directly compensated by actuators, such as schützee servomotors of the weapon. 10. The method according to any one of claims 7 to 9, characterized in that a failure of individual temperature sensors (p1 -p16) is compensated by a mathematical model. 1 1. A method according to claim 10, characterized in that the evaluation algorithm contains various fallback levels in the event that several temperature sensors (p1 -p16) fail. 12. The method according to any one of claims 7 to 1 1, characterized in that the inherent inertia of the system is taken into account. 13. The method according to any one of claims 7 to 12, characterized in that time profiles of the temperature correlation function are recorded. 14. The method according to claim 13, characterized in that the temporal course (s) for later maintenance work are also stored in the gun computer in readable form.