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 measurement 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 structures, and especially in measuring the inclination of underwater vehicles, particularly submersibles. PRIOR TECHNOLOGY

[0004] It is known from the prior art of techniques for measuring the inclination of structures of all types.

[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, comprising 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 deviation of the ball from the stable position indicating an inclination of the structure.

[0007] Such inclinometers generally allow the measurement of large variations in the inclination of a structure, for example of + / - 40 degrees around a reference position of the structure.

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

[0009] The present invention relates to an inclinometer which is particularly simple, convenient and compact, and which allows a 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 the 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 opposing ends, each end being subject to translation and rotation on the frame, - an amplifying mechanism, comprising a driven member attached to the pendulum arm between said ends, and a driving member attached 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.

[0011] In the inclinometer according to the invention, when the structure tilts, the frame follows this inclination 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 which the frame and the pendulum follow causes a pivoting of the pendulum arm, which is mobile relative to the frame, thanks to the amplifying mechanism whose driving member attached to the pendulum drives the driven member attached to the pendulum arm.

[0013] Due to the transmission ratio of the amplifier mechanism which is strictly greater than 1, the pendulum 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 pendulum arm is representative of the relative inclination between the frame and the pendulum, and therefore of the inclination of the structure with respect to a reference position.

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

[0016] Moreover, the inclinometer according to the invention allows a particularly precise measurement of the inclination while being particularly compact, the multiplication 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 pendulum arm.

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

[0018] Finally, the inclinometer according to the invention is mechanical and entirely energy-passive, the pendulum arm being driven solely by the kinematic differential. between the frame, which tilts with the structure, and the pendulum, which remains essentially oriented in the direction of the local gravitational field. This makes it possible to obtain information about the inclination of the structure even in the event that 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 craft, which is a structure exhibiting relatively slow and progressive variations in inclination, i.e. accelerations.

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

[0021] The driven member includes a fixed pinion and the driving member includes teeth 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 arc of an internally toothed gear.

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

[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 include an indicator device intended to indicate the inclination of the structure, the indicator device comprising a visual identification element mechanically connected to one of the ends of the pendulum arm, and a window arranged in a wall of the frame opposite said first end of the pendulum arm.

[0027] The visual identification device may include a movable cursor and the indicating device may further include a graduated scale juxtaposed to or applied to the window.

[0028] The frame may include 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 include a first guide track and a second guide track arranged substantially parallel on the frame, and include a first carriage and a second carriage respectively subjected 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 can also be respectively subjected to translation at the said opposite ends of the rocker arm, in a direction of translation which is substantially orthogonal to the said guide tracks.

[0031] The pendulum may include a first end by which it is subjected to rotation to the frame, and a second end opposite to the first end, the pendulum may further include an unbalanced 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 attached to the structure.

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

[0034] Other advantages, purposes and special features of the present invention will become apparent 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 accompanying drawings.

[0035] Fig. 1 illustrates in perspective an inclinometer according to one embodiment, in a zero inclination configuration of a structure.

[0036] [Fig.2] illustrates, according to a cross-sectional view in elevation and side view, rinclinometer of [Fig.1].

[0037] Fig. 3 illustrates, according to a cross-sectional view in elevation and side view, the rinclinometer 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 an elevation cross-sectional view and seen in perspective.

[0039] Fig. 5 illustrates, according to a cross-sectional view in elevation and side view, the inclinometer of Fig. 1, but in a second configuration of positive inclination of the structure.

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

[0041] The present description is given by way of non-limiting grammar, each feature of an embodiment being able to be advantageously combined with any other feature of any other embodiment.

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

[0043] Figure 1 illustrates in perspective an inclinometer 1 according to the invention, according to an example of an 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 includes a frame 2 intended to be rigidly attached to a structure (not shown), i.e. so that a given inclination of the structure corresponds to the same inclination of the inclinometer.

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

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

[0049] The inclinometer 1 includes a visual indicator device 4 for visually indicating 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 angle of trim of the vehicle with respect 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.1 in a side elevation cross-sectional view in a zero inclination configuration of the structure.

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

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

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

[0056] Optionally, the main faces 5 and / or the side walls 6 may include one or more reinforcing ribs, which increases 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 includes a pendulum 8, which is here freely suspended from the frame 2 inside the cavity 7.

[0059] In the illustrated example, the pendulum 8, which has 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 include a first opening 11 (visible in particular in Figures 4 and 6) and the frame 2 may include a finger 12 protruding from one of the main faces 5 of the frame 2 and into which the pendulum 8 is inserted by its first opening 11.

[0060] The pendulum 8 can further include, 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 regardless of 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 includes an amplifier mechanism, allowing a tilting movement of the structure to be mechanically amplified to obtain an amplified movement at the level of the indicator device 4.

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

[0064] The inclinometer includes a pendulum 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 illustrated example, the rocker arm 14 is movable in translation within a plane, here substantially parallel to the principal faces 5, and mobile in rotation around an axis substantially orthogonal to this plane.

[0067] For this purpose, the inclinometer 1 may include 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 it.

[0068] In the illustrated example, 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 subjected to rotation to the first carriage 17 by its first end 19 and to the second carriage 18 by its second end 20.

[0071] In addition, the rocker arm 14 can also be subjected 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 with respect 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 include a first pin 21 and a second pin 22, and the first carriage 17 and the second carriage 18 may each include a groove 23, substantially orthogonal to the direction of guidance of the carriages 17 and 18, and in grooves 23 the pins 21 and 22 can respectively slide (visible in particular in Figures 3 to 6).

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

[0075] The fixed pinion 24 is mechanically fixed to the rocker arm 14, without degrees 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 balance 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 teeth 25 are mechanically fixed to the pendulum 8, without rotational degrees of freedom, preferably near the first end 9 of the pendulum 8.

[0079] In the illustrated example, the teeth are a portion of an arc of an internally toothed gear.

[0080] The fixed pinion 24 is here an externally toothed gear.

[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 causes in particular a pivoting of the pendulum arm 14 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 rocker 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 on the driving gear (here, the tooth 25 – in the case of a portion of a gear arc, the number of teeth on the entire gear should be considered hypothetically) to the number of teeth on the driven gear (here, the fixed pinion 24). In the case of gears of the same module, this ratio corresponds equivalently to the ratio of the diameters of the driving gear and the driven gear.

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

[0087] In the illustrated example, the transmission ratio is strictly greater than 1, so that, when there is a relative inclination between the frame 2 and the pendulum 8 of a first predetermined angle, the pendulum 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 include a visual identification element 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 element 26 here includes a cursor, which is attached to the first carriage 17, and therefore indirectly attached to the first end 19 of the rocker arm 14, thus allowing its movement to be indicated.

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

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

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

[0096] According to an alternative, the graduated scale 28 can be applied to the window 27, for example by painting or gluing.

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

[0098] Advantageously, the side wall 6 which includes 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 is overhanging the structure to which the inclinometer 1 is subjected.

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

[0101] We will now briefly describe the operation of rinclinometer 1 when 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, that is to say equal to 0 degrees.

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

[0104] Such a configuration of rinclinometer 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 with respect to the horizontal.

[0106] Consequently, the frame 2 is also inclined with respect 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 pendulum 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 device 26 is located opposite a graduation on the graduated scale 28 indicating a negative inclination of 10 degrees.

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

[0111] In a manner similar to what is described above, the frame 2 is then inclined with respect 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 pendulum 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 device 26 is located opposite a graduation on 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 shown 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 specifically the rotational component of the movement of the rocker arm 14 that 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 unillustrated embodiments are described below.

[0120] - In the amplifier mechanism, the driven element may include a fixed roller The pendulum is attached to the rocker arm at its ends, and the driving element may include a curved track configured to drive the fixed roller in motion by friction. In other words, the fixed roller and the curved track are in frictional contact; a relative rotation of the pendulum with respect to the frame causes the fixed roller to roll on the curved track, thus pivoting the rocker arm. The transmission ratio between the curved track and the fixed roller is approximately equal to the ratio of the radius of curvature of the curved track to the radius of the fixed roller.

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

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

[0123] - Alternatively, the side wall containing the indicator device may be flat without however being inclined with respect to the base nor projected with respect to the base, and can for example be orthogonal to the base.

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

Claims

Demands

1. 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, the inclinometer being characterized in that it comprises: - a pendulum arm (14), movable relative to the frame (2), comprising two opposite ends (19, 20), 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 (14) between said ends (19, 20), and a driving member fixed to the pendulum (8) and configured to drive the driven member in motion, the amplifying mechanism being configured to pivot the pendulum 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,and in that it further 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 subjected 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).

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 teeth (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 an arc of an internally toothed gear.

5. An inclinometer (1) according to claim 1, characterized in that the driven member comprises a fixed roller attached 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 with it.

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) for indicating 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 indicating device (4) further comprises a graduated scale (28) juxtaposed to or applied to the window (27).

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 with respect to said base (3).

10. Inclinometer (1) according to any one of claims 1 to 9, characterized in that the first carriage (17) and the second carriage (18) are further respectively subjected to translation at said opposite ends (19, 20) of the swing arm, in a direction of translation which is substantially orthogonal to said guide tracks (15, 16).

11. Inclinometer (1) according to any one of claims 1 to 10, characterized in that the pendulum (8) has a first end (9) by which it is subjected 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).

12. Structure comprising an inclinometer (1) according to any one of claims 1 to 11, wherein the frame (2) of the inclinometer is rigidly attached to the structure.

13. Structure according to claim 12, the structure being an underwater craft, and preferably an underwater vehicle.

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