Inclinometer for measuring the inclination of a structure and structure including such an inclinometer

Abstract

The invention relates to an inclinometer (1) for measuring the inclination of a structure, the inclinometer comprising: - a frame (2) intended to be rigidly fixed to the structure; - a pendulum (8) freely suspended from the frame, - a pendulum arm (14) comprising two opposite ends, each of the ends being subjected to translation and rotation to the frame, - an amplifying mechanism, comprising a driven member fixed to the pendulum arm between said ends, and a driving member fixed to the pendulum and configured to drive the driven member in motion, the amplifying mechanism being configured to pivot the pendulum arm during a relative inclination between the frame and the pendulum, according to a transmission ratio between the driving member and the driven member strictly greater than 1.The invention also relates to a structure, in particular an underwater craft and more particularly an underwater vehicle, equipped with such an inclinometer. See Figure 2 for the abbreviation.

Description

Title of the invention: Inclinometer for measuring the inclination of a structure and structure comprising such an inclinometer TECHNICAL FIELD OF THE INVENTION

[0001] The field of the invention is that of physical measuring devices, in particular the measurement of the inclination of structures.

[0002] More specifically, the invention relates to an inclinometer for measuring the inclination of a structure, and a structure comprising such an inclinometer.

[0003] The invention finds applications in measuring the inclination of structures, particularly naval and aquatic, and in particular in measuring the inclination of underwater vehicles, particularly underwater vehicles such as submersibles. STATE OF THE ART

[0004] Techniques for measuring the inclination of structures of any type are known from the prior art.

[0005] For example, liquid bubble inclinometer techniques are known, which comprise a tube containing a liquid and an air bubble. The position of the bubble in the tube is an indicator of the inclination of the structure, relative to a reference position.

[0006] Liquid ball inclinometer techniques are also known, which comprise a tube containing a liquid and a ball immersed in the liquid. The tube is slightly curved, so that the ball has a stable position in a reference position of the structure, a separation of the ball from the stable position indicating a tilt of the structure.

[0007] Such inclinometers generally make it possible to measure large variations in the inclination of a structure, for example + / - 40 degrees around a reference position of the structure.

[0008] When it is desirable to measure small variations in inclination of a structure without loss of accuracy, for example + / - 10 degrees around a reference position of the structure, it is possible to amplify the reading accuracy of such a bubble or ball inclinometer by enlarging the size of the device. Statement of the invention

[0009] The present invention aims at an inclinometer which is particularly simple, convenient and compact, and which allows precise measurement of the inclination of a structure even in the case of small variations in inclination.

[0010] The invention relates to an inclinometer for measuring an inclination of a structure, the inclinometer comprising: - a frame intended to be rigidly attached to the structure; - a pendulum freely suspended from the frame, - a rocker arm comprising two opposite ends, each of the ends being subject to translation and rotation on the frame, - an amplifier mechanism, comprising a driven member secured to the balance arm between said ends, and a driving member secured to the pendulum and configured to drive the driven member into movement, the amplifier mechanism being configured to pivot the balance arm during a relative inclination between the frame and the pendulum, according to a transmission ratio between the driving member and the driven member strictly greater than 1.

[0011] In the inclinometer according to the invention, when the structure tilts, the frame follows this tilt while the pendulum suspended from the frame remains substantially in the same position, that is to say substantially oriented in the direction of the local gravitational field.

[0012] This difference in kinematics followed by the frame and the pendulum causes a pivoting of the balance arm, which is mobile relative to the frame, thanks to the amplifier mechanism whose driving member subject to the pendulum drives the driven member subject to the balance arm.

[0013] Due to the transmission ratio of the amplifier mechanism which is strictly greater than 1, the balance arm is driven according to an amplified pivoting movement, multiplying the relative tilting movement between the frame and the pendulum.

[0014] The pivoting of the balance arm is representative of the relative inclination between the frame and the pendulum, and therefore of the inclination of the structure relative to a reference position.

[0015] This results in a particularly precise measurement of the inclination thanks to this reduction in the relative inclination movement between the frame and the pendulum, and the effect of which is particularly beneficial in particular when the relative inclination angle between the frame and the pendulum is small.

[0016] Furthermore, the inclinometer according to the invention allows a particularly precise measurement of the inclination while being particularly compact, the reduction of the movement being obtained by the transmission ratio strictly greater than 1, without requiring the enlargement of the components of the inclinometer, and in particular of the rocker arm.

[0017] The inclinometer also allows for particularly convenient reading, the range of inclination indication corresponding substantially to the amplitude of pivoting of the rocker arm.

[0018] Finally, the inclinometer according to the invention is mechanical and entirely passive energetically, the rocker arm being moved solely by the kinematic differential between the frame which tilts with the structure and the pendulum which remains substantially oriented in the direction of the local gravitational field. This makes it possible to obtain information on the inclination of the structure even in the case where other devices for measuring the inclination of the structure, powered by an external energy source, are faulty.

[0019] The inclinometer according to the invention is particularly suitable for use in an underwater vehicle, which is a structure exhibiting variations in inclination, i.e. accelerations, which are relatively slow and progressive.

[0020] Preferred, simple and convenient features of the inclinometer according to the invention are presented below.

[0021] The driven member comprises a fixed pinion and the driving member comprises a toothing configured to mesh with the fixed pinion.

[0022] The teeth and the fixed pinion together form an internal cylindrical gear.

[0023] Said teeth are formed by a portion of an internally toothed toothed wheel arc.

[0024] According to an alternative embodiment, the driven member comprises a fixed roller secured to the rocker arm between said ends and the driving member comprises a curved track, configured to drive the fixed roller into motion by friction therewith.

[0025] Preferably, said transmission ratio is greater than 3, preferably greater than 4, and even more preferably greater than 5.

[0026] The inclinometer may further comprise an indicator device for indicating the inclination of the structure, the indicator device comprising a visual identification member mechanically connected to a first of the ends of the rocker arm, and a window arranged in a wall of the frame opposite said first end of the rocker arm.

[0027] The visual identification member may comprise a movable cursor and the indicator device may further comprise a graduated scale juxtaposed with the window or applied thereto.

[0028] The frame may comprise a base and the wall of the frame in which the window is arranged may be inclined and projected relative to said base.

[0029] The inclinometer may comprise a first guide track and a second guide track arranged substantially parallel on the frame, and comprise a first carriage and a second carriage respectively subject to rotation at opposite ends of the rocker arm and respectively guided in translation on the first guide track and on the second guide track.

[0030] The first carriage and the second carriage may further be respectively subject to translation at said opposite ends of the rocker arm, in a translation direction which is substantially orthogonal to said guide tracks.

[0031] The pendulum may comprise a first end by which it is subject to rotation on the frame, and a second end opposite the first end, the pendulum being able to further comprise an unbalance mass at its second end.

[0032] The invention also relates, according to a second aspect, to a structure comprising an inclinometer as described above, in which the inclinometer frame is rigidly secured to the structure.

[0033] Preferably, the structure is an underwater vehicle, and more preferably an underwater vehicle. BRIEF DESCRIPTION OF THE FIGURES

[0034] Other advantages, aims and particular characteristics of the present invention will emerge from the following non-limiting description of at least one particular embodiment of the device which is the subject of the present invention, with reference to the appended drawings.

[0035] [Fig.l] illustrates in perspective an inclinometer according to one embodiment, in a zero inclination configuration of a structure.

[0036] [Fig.2] illustrates, in a sectional view in elevation and seen from the side, the inclinometer of [Fig.l].

[0037] [Fig.3] illustrates, in a sectional view in elevation and seen from the side, the inclinometer of [Fig.1], but in a first configuration of negative inclination of the structure.

[0038] [Fig.4] is similar to [Fig.3], showing the inclinometer in a sectional view in elevation and in perspective.

[0039] [Fig.5] illustrates, in a sectional view in elevation and seen from the side, the inclinometer of [Fig.l], but in a second configuration of positive inclination of the structure.

[0040] [Fig.6] is similar to [Fig.5], showing the inclinometer in a sectional view in elevation and in perspective. DETAILED DESCRIPTION OF THE INVENTION

[0041] The present description is given without limitation, each characteristic of an embodiment being able to be combined with any other characteristic of any other embodiment in an advantageous manner.

[0042] It should be noted, from now on, that the figures are not necessarily to scale.

[0043] [Fig.l] illustrates in perspective an inclinometer 1 according to the invention, according to an exemplary embodiment.

[0044] An inclinometer is a measuring device intended to indicate the inclination, as well as the variation in inclination, of a structure, relative to a reference position.

[0045] For example, the structure is an underwater craft, and more particularly an underwater vehicle, such as a submersible or even an underwater drone.

[0046] The inclinometer 1 comprises a frame 2 intended to be rigidly secured to a structure (not shown), that is to say so that a given inclination of the structure corresponds to the same inclination of the inclinometer.

[0047] The frame 2 may comprise a base 3 by which it is rigidly secured to the structure, for example by screwing.

[0048] In particular, when the structure is an underwater vehicle, the frame 2 can be rigidly secured to a structural element of a cockpit of such a vehicle.

[0049] The inclinometer 1 comprises a visual indicator device 4 making it possible to visually indicate the inclination of the structure relative to a reference frame.

[0050] Preferably, the inclination of the structure is indicated in degrees, for example over a range of + / - 10 degrees, around a reference position (corresponding here to an inclination of 0 degrees).

[0051] In particular, when the structure is an underwater vehicle, the indicator device 4 makes it possible to indicate the attitude angle of the vehicle relative to a horizontal reference position of the vehicle, that is to say a position substantially orthogonal to the direction of the local gravitational field.

[0052] [Fig.2] shows the inclinometer 1 shown in [Fig.l] in a side elevation sectional view, in a zero inclination configuration of the structure.

[0053] Figures 3 and 4 show in section, respectively from the side and in perspective, the inclinometer 1 in a first negative inclination configuration.

[0054] Figures 5 and 6 show in section, respectively from the side and in perspective, the inclinometer 1 in a second positive inclination configuration.

[0055] The frame 2 here comprises a housing of substantially straight prismatic shape, comprising two opposite main faces 5 and a plurality of side walls 6 connecting the opposite main faces 5, and of which one of the side walls 6 forms the base 3 and another of the side walls 6 comprises at least in part the indicator device 4.

[0056] Optionally, the main faces 5 and / or the side walls 6 may comprise one or more reinforcing ribs, which makes it possible to increase the rigidity of the frame 2.

[0057] The main faces 5 and the side walls 6 together define a closed housing delimiting a cavity 7.

[0058] The inclinometer 1 further comprises a pendulum 8, which is here freely suspended from the frame 2 inside the cavity 7.

[0059] In the example illustrated, the pendulum 8, which comprises a first end 9 and a second end 10 opposite the first end 9, is suspended by its first end 9 from the frame 2. For this purpose, the pendulum 8 may comprise a first opening 11 (visible in FIGS. 4 and 6 in particular) and the frame 2 may comprise a finger 12 projecting from one of the main faces 5 of the frame 2 and on which the pendulum 8 is inserted through its first opening 11.

[0060] The pendulum 8 may further comprise, at its second end 10, an unbalance mass 13, which makes it possible to increase the inertia of the pendulum 8.

[0061] The pendulum 8 is intended to maintain substantially the same orientation whatever the inclination of the frame 2 to which it is freely subjected in rotation, under the effect of the gravitational field local to the structure.

[0062] The inclinometer 1 also comprises an amplifier mechanism, making it possible to mechanically amplify a tilting movement of the structure to obtain an amplified movement at the level of the indicator device 4.

[0063] This results in an inclinometer of increased precision, even in the event of small variations in the inclination of the structure.

[0064] The inclinometer comprises a balance arm 14, which is movable relative to the frame 2, and which is configured to be driven in particular in pivoting by the pendulum 8.

[0065] The rocker arm 14 is subject to translation and rotation to the frame 2.

[0066] In the example illustrated, the rocker arm 14 is movable in translation in a plane, here substantially parallel to the main faces 5, and mobile in rotation around an axis substantially orthogonal to this plane.

[0067] For this purpose, the inclinometer 1 may comprise a first guide track 15 and a second guide track 16 which are arranged substantially parallel to each other on the frame 2 and mechanically secured to the latter.

[0068] In the example illustrated, the first guide track 15 and the second guide track 16 are substantially parallel to the side wall 6 comprising the indicator device 4.

[0069] The inclinometer 1 may further comprise a first carriage 17, guided in translation on the first guide track 15, and a second carriage 18, guided in translation on the second guide track 16.

[0070] The rocker arm 14, which has a first end 19 and a second end 20 opposite the first end 19, is subject to rotation to the first carriage 17 by its first end 19 and to the second carriage 18 by its second end 20.

[0071] Furthermore, the rocker arm 14 can also be subject to translation to the first carriage 17 by its first end 19 and to the second carriage 18 by its second end 20.

[0072] In particular, the direction of translation of the rocker arm 14 relative to the carriages is substantially orthogonal to the direction of guidance of the first guide track 15 and second guide track 16.

[0073] For example, the rocker arm 14 may comprise a first pin 21 and a second pin 22, and the first carriage 17 and the second carriage 18 may each comprise a groove 23, substantially orthogonal to the guiding direction of the carriages 17 and 18, and in which grooves 23 the pins 21 and 22 can respectively slide (visible in figures 3 to 6 in particular).

[0074] In the illustrated example, the driven member comprises a fixed pinion 24.

[0075] The fixed pinion 24 is mechanically secured to the rocker arm 14, without any degree of freedom in rotation, between the first end 19 and the second end 20 of the rocker arm 14.

[0076] Here, the fixed pinion 24 is closer to the second end 20 of the rocker arm 14, than to the first end 19.

[0077] In the illustrated example, the driving member comprises a toothing 25 configured to mesh with the fixed pinion 24.

[0078] The toothing 25 is mechanically secured to the pendulum 8, without any degree of freedom in rotation, preferably close to the first end 9 of the pendulum 8.

[0079] In the example illustrated, the toothing is a portion of a toothed wheel arc with internal teeth.

[0080] The fixed pinion 24 is here a toothed wheel with external teeth.

[0081] In this example, the fixed pinion 24 and the teeth 25 which are in mesh form together an internal cylindrical gear.

[0082] When the frame 2 tilts relative to the pendulum 8, the pendulum 8 notably causes the balance arm 14 to pivot relative to the frame 2, around the fixed pinion 24.

[0083] Advantageously, the transmission ratio between the teeth 25 and the fixed pinion 24 is strictly greater than 1.

[0084] In other words, the amplifier mechanism is configured to pivot the balance arm 14 during a relative inclination between the frame 2 and the pendulum 8, according to a transmission ratio between the driving member and the driven member strictly greater than 1.

[0085] The transmission ratio of a gear can be determined by the ratio of the number of teeth of the driving toothed wheel (here, the toothing 25 - in the case of a portion of a toothed wheel arc, the number of teeth of the entire toothed wheel should be considered fictitiously) with the number of teeth of the driven toothed wheel (here, the fixed pinion 24). In the case of toothed wheels of the same module, this ratio corresponds equivalently to the ratio of the diameters of the driving toothed wheel and the driven toothed wheel.

[0086] Conversely, the transmission ratio indicates the number of revolutions made by the driven gear wheel when the driving gear wheel makes one revolution.

[0087] In the example illustrated, the transmission ratio is strictly greater than 1, so that, during a relative inclination between the frame 2 and the pendulum 8 of a first predetermined angle, the balance arm 14 pivots by a second angle greater than the first predetermined angle.

[0088] Preferably, the transmission ratio may be greater than 1.5; greater than 2; greater than 3; greater than 4; greater than 5; greater than 6; greater than 7; greater than 8; greater than 9; or even greater than 10.

[0089] Preferably, the transmission ratio is less than 20.

[0090] Advantageously, the indicator device 4 may comprise a visual identification member 26, as well as a transparent or translucent window 27.

[0091] The window 27 is for example arranged in the side wall 6 which is opposite the first end 19 of the rocker arm 14.

[0092] The visual identification member 26 here comprises a cursor, which is secured to the first carriage 17, and therefore indirectly secured to the first end 19 of the rocker arm 14, thus making it possible to indicate its movement.

[0093] The cursor is arranged so as to face the window 27, and may for example be brightly colored and / or luminescent, in order to allow particularly easy visual identification of the position of the cursor.

[0094] According to an alternative, the window 27 can be arranged on one of the main faces 5, and the visual identification member can be arranged on the first carriage 17 facing said main face 5.

[0095] The indicator device 4 may further comprise a graduated scale 28 juxtaposed with the window 27, for example painted or glued on the side wall 6 which comprises the window 27.

[0096] Alternatively, the graduated scale 28 may be applied to the window 27, for example by painting or gluing.

[0097] The graduated scale 28 may comprise graduations and the cursor may, for example, be in the form of an arrow directed towards the graduations, to allow easier visual identification.

[0098] Advantageously, the side wall 6 which comprises the window 27 can be inclined and projected relative to the side wall 6 forming the base 3.

[0099] In other words, the side wall 6 which includes the window 27 and the side wall 6 forming the base 3 form an obtuse angle inside the cavity 7, and the side wall 6 which includes the window 27 overhangs the structure to which the inclinometer 1 is attached.

[0100] In particular when the structure is an underwater vehicle, this allows better reading of the indicator device 4 in particular when the trim angle of the vehicle is negative.

[0101] We will now briefly describe the operation of the inclinometer 1 when it is used to measure the inclination of a structure, which is for example an underwater vehicle.

[0102] When the underwater vehicle is submerged horizontally, for example while moving, its trim angle is substantially zero, i.e. equal to 0 degrees.

[0103] The rocker arm 14 is in a reference angular position relative to the frame 2, and the indicator device 4 of the inclinometer indicates an inclination of 0 degrees.

[0104] Such a configuration of the inclinometer 1 is illustrated in Figures 1 and 2.

[0105] When the underwater vehicle dives, its trim angle becomes negative, the underwater vehicle then being inclined relative to the horizontal.

[0106] Consequently, the frame 2 is also inclined relative to the horizontal. However, the pendulum 8 remains substantially vertical, in the direction of the local gravitational field.

[0107] The difference in kinematics between the frame 2 and the pendulum 8 causes the balance arm 14 to pivot in a first direction, and the first end 19 slides downwards on the first guide track 15, and the second end 20 slides upwards on the second guide track 16.

[0108] The rocker arm 14 also slides slightly in the grooves 23 of each of the carriages 17 and 18.

[0109] In the example illustrated in Figures 3 and 4, the underwater vehicle has a negative trim angle of 10 degrees, and the cursor of the visual identification member 26 is located opposite a graduation of the graduated scale 28 indicating a negative inclination of 10 degrees.

[0110] Conversely, when the underwater vehicle rises, its trim angle becomes positive, the underwater vehicle then being inclined relative to the horizontal but in an opposite direction.

[0111] In a similar manner to what is described above, the frame 2 is then inclined relative to the horizontal and the pendulum 8 remains substantially vertical, in the direction of the local gravitational field.

[0112] The difference in kinematics between the frame 2 and the pendulum 8 causes the balance arm 14 to pivot in a second direction, and the first end 19 slides upwards on the first guide track 15, and the second end 20 slides downwards on the second guide track 16.

[0113] The rocker arm 14 also slides slightly in the grooves 23 of each of the carriages 17 and 18.

[0114] In the example illustrated in Figures 5 and 6, the underwater vehicle has a positive trim angle of 10 degrees, and the cursor of the visual identification member 26 is located opposite a graduation of the graduated scale 28 indicating a positive inclination of 10 degrees.

[0115] In the examples illustrated in Figures 3 to 6, the pivot angle of the rocker arm 14 relative to its reference position illustrated in [Fig.2] is approximately + / - 40 degrees, while the trim angle of the underwater vehicle is approximately + / - 10 degrees.

[0116] Generally, the pivot angle of the rocker arm 14 relative to its reference position, for a trim angle of the underwater vehicle of approximately + / - 10 degrees, can advantageously be between approximately + / - 15 degrees and + / - 100 degrees.

[0117] It should be noted that the movement of the rocker arm 14 is a compound movement, including in particular the pivoting, i.e. the rotation, described above, as well as a translation in the plane orthogonal to the axis of rotation. However, it is a particular rotary component of the movement of the rocker arm 14 which serves as an indicator of the inclination of the structure.

[0118] The inclinometer as described above in a non-limiting manner allows a particularly precise indication of the inclination of the structure, while being particularly compact and entirely energy passive.

[0119] Other variant embodiments not illustrated are described below.

[0120] - In the amplifier mechanism, the driven member may comprise a fixed roller secured to the pendulum arm between its ends, and the driving member may comprise a curved track, configured to drive the fixed roller into motion by friction therewith. In other words, the fixed roller and the curved track are in frictional contact, a relative rotation of the pendulum relative to the frame causing the fixed roller to roll on the curved track, thereby causing the pendulum arm to pivot. The transmission ratio between the curved track and the fixed roller corresponds substantially to the ratio of the radius of curvature of the curved track and the radius of the fixed roller.

[0121] - The housing forming the frame of the inclinometer may be of a shape other than that re presented, and can be in particular cylindrical, circular or even parallelepipedal, rectangular.

[0122] - In particular, the side wall comprising the indicator device, and in particular the window, can be curved.

[0123] - Alternatively, the side wall comprising the indicator device may be flat. without however being inclined with respect to the base or projected with respect to the base, and can for example be orthogonal to the base.

[0124] It is recalled more generally that the invention is not limited to the examples described and illustrated.

Claims

Claims

1. Inclinometer (1) for measuring an inclination of a structure, the inclinometer comprising: - a frame (2) intended to be rigidly secured to the structure; - a pendulum (8) freely suspended from the frame, characterized in that the inclinometer further comprises: - a balance arm (14) comprising two opposite ends (19, 20), each of the ends being subject to translation and rotation to the frame, - an amplifier mechanism, comprising a driven member secured to the balance arm (14) between said ends (19, 20), and a driving member secured to the pendulum (8) and configured to drive the driven member in movement, the amplifier mechanism being configured to pivot the balance arm (14) during a relative inclination between the frame (2) and the pendulum (8), according to a transmission ratio between the driving member and the driven member strictly greater than 1.

2. Inclinometer (1) according to claim 1, characterized in that the driven member comprises a fixed pinion (24) and in that the driving member comprises a toothing (25) configured to mesh with the fixed pinion (24).

3. Inclinometer (1) according to claim 2, characterized in that the toothing (25) and the fixed pinion (24) together form an internal cylindrical gear.

4. Inclinometer (1) according to any one of claims 2 and 3, characterized in that said toothing (25) is formed by a portion of a toothed wheel arc with internal teeth.

5. An inclinometer (1) according to claim 1, characterized in that the driven member comprises a fixed roller secured to the rocker arm between said ends and in that the driving member comprises a curved track, configured to drive the fixed roller into motion by friction therewith.

6. Inclinometer (1) according to any one of claims 1 to 5, characterized in that said transmission ratio is greater than 3, preferably greater than 4, and even more preferably greater than 5

7. Inclinometer (1) according to any one of claims 1 to 6, characterized in that it comprises an indicator device (4) intended to indicate the inclination of the structure, the indicator device comprising a visual identification member (26) mechanically connected to a first of the ends (19) of the rocker arm (14), and a window (27) arranged in a wall (6) of the frame opposite said first end (19) of the rocker arm (14).

8. Inclinometer (1) according to claim 7, wherein the visual identification member (26) comprises a movable cursor and the indicator device (4) further comprises a graduated scale (28) juxtaposed with the window (27) or applied thereto.

9. Inclinometer (1) according to any one of claims 7 and 8, characterized in that the frame (2) comprises a base (3) and in that the wall (6) of the frame in which the window (27) is arranged is inclined and projected relative to said base (3).

10. Inclinometer (1) according to any one of claims 1 to 9, characterized in that it comprises a first guide track (15) and a second guide track (16) arranged substantially parallel on the frame (2), and in that it comprises a first carriage (17) and a second carriage (18) respectively subject to rotation at opposite ends (19, 20) of the rocker arm and respectively guided in translation on the first guide track (15) and on the second guide track (16).

11. Inclinometer (1) according to claim 10, characterized in that the first carriage (17) and the second carriage (18) are further respectively subject to translation at said opposite ends (19, 20) of the rocker arm, in a translation direction which is substantially orthogonal to said guide tracks (15, 16).

12. Inclinometer (1) according to any one of claims 1 to 11, characterized in that the pendulum (8) comprises a first end (9) by which it is subject to rotation to the frame (2), and a second end (10) opposite the first end (9), the pendulum further comprising an unbalance mass (13) at its second end (10).

13. A structure comprising an inclinometer (1) according to any one of claims 1 to 12, wherein the frame (2) of the inclinometer is rigidly secured to the structure.

14. Structure according to claim 13, the structure being an underwater vehicle, and preferably an underwater vehicle.

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