FR2612717A1 - MICROPHONE MOUNT FOR USE WITH A TRANSMISSION SYSTEM - Google Patents

Abstract

THE INVENTION RELATES TO A MICROPHONE MOUNT FOR USE IN AN AUTOMOTIVE COMMUNICATIONS SYSTEM. THE FRAME CONSISTS OF TWO BASES 18, 20 AND A COVER 22. THE LOWER BASE 18 RECEIVES A MICROPHONE CARTRIDGE 24 AND IT HAS OPPOSED FINGERS 44 WHICH DEFINE WITH THIS BASE A RETAINING ZONE OF A SAFETY BELT. THE ASSEMBLY CAN THUS SLIDE ALONG THE BELT AND PLACE THE FRAME IN ANY DESIRED POSITION ON THE BELT. FIELD OF APPLICATION: TELEPHONE EQUIPMENT FOR VEHICLES.

Description

The invention relates to a mounting of a microphone system to be used

  in an automobile. More particularly, the invention relates to an improved microphone and microphone mount for use without hands in a transmission system for automobiles, such as

  than a mobile cell phone.

  Portable phones used in automobiles have become commonplace, particularly with the advent of cellular telephone systems in the United States of America. Typically, such car telephone systems include handsets containing both the speaker and the telephone microphone and having a configuration very similar to that of a conventional telephone handset. Although conventional handsets are effective and useful, they ask the

  driver of an automobile to assign an exclusive

  phone maneuver, so that he only has the other hand to drive the vehicle. This situation naturally leads to important safety considerations and poses problems of inconvenience and difficulty in using when a driver tries to maneuver the mobile phone at the same time as negotiating a turn or parking the car, for example . These problems are especially prevalent in vehicles equipped with a conventional transmission system, where the driver and user of the phone often have to use one hand to maneuver the steering wheel and the other hand

  to operate the gearshift mechanism.

  Maneuvering without the hands of the cellular transmission system requires that the microphone be located elsewhere than in a handset, which necessarily means that the microphone is further away from the mouth of the speaker. However, moving the microphone away from the immediate vicinity of the mouth leads to difficult problems with background noise. So, the main acoustic problem facing the designer of a hands-free microphone system is the

  need to maintain a high signal-to-noise ratio.

  The level of noise in a vehicle varies between the private vehicles and the running conditions of the vehicle. For example, the speed of the vehicle, the surface of the road traveled and the accessory equipment in use in the vehicles (such as an air conditioner and a fan, or the vehicle radio) can all add to the noise of the vehicle. main background, namely the sounds of the wind and the engine. In general, the microphone must be

  designed for use in a noisy environment.

  Although the noise level varies slightly at different points in a moving vehicle, it is almost always sufficient to significantly degrade the sound pickup when the microphones are placed at a distance

  important from the mouth of the user. For the sake of

  the concept of a vehicle microphone, a reasonable approximation may be

  noise is uniform throughout the vehicle.

  The problem of use without the hands then becomes the maintenance of a high signal-to-noise ratio for a microphone remote from the mouth of the speaker. A logical location for such a microphone is the steering wheel of the automobile; in most vehicles, this location is about 40 cm or more from the driver's mouth. Since the

  direct sound pressure resulting from the voice is inverse-

  proportionally to the distance from the mouth to the microphone, a microphone mounted about 40 cm from the mouth is only 1/16 of the sound pressure of a microphone in a telephone handset placed approximately 2.5 cm from the mouth. A distance of cm thus causes a reduction of about 24 decibels in the signal strength; a reduction of 24 decibels can

  easily result in an unacceptable signal-to-noise ratio.

  Other arrangements for setting up a microphone are feasible, but generally inefficient. Although the problem can be alleviated somewhat by using directional microphones, the situation remains essentially a problem of reducing the distance from the microphone to the mouth of the speaker. These problems can usually be avoided by the use of a helmet mounted "boom" microphone, and such helmets have been made and used in the prior art. However, boom microphone and helmet arrangements require significant user resistance and generally lack proper marketing opportunities. Other arrangements tried in the prior art are less effective than either the use of a boom microphone or the mounting of the microphone on the steering wheel. For example, microphones mounted on the rearview mirror of an automobile are also at least 40 cm or more from the user's mouth with, therefore, an unacceptable reduction in sound quality. In addition, the location of the mirror is extremely sensitive to wind noise, especially the noise produced by the pull of an air conditioner fan or an open window. In addition, the position of the mirror

  is not ideal because the voice of the driver of an auto-

  mobile is usually directed more downwards. The dashboard microphones are positioned more toward the voice of the speaker, but are further away from the driver's mouth than the microphones on the steering wheel. Windows or similar locations present many of these same difficulties. In summary, any microphone position more than about 15 cm from the mouth

  to result in an unwanted signal / noise.

  The object of the invention is therefore to propose a microphone and its mount for use in a

  mobile transmission system on automobile.

  Another object of the invention is to provide such a microphone and such a mount, easy to use and allowing the driver of the vehicle to dispose freely

  with both hands for driving the vehicle.

  Another object of the invention is to provide a microphone and its mount, "hands free", for use in a vehicle transmission system, placed at a distance of not more than about 15 cm from the mouth of the user.

  The invention also relates to a micro-

  phone and its mount for use in a transmission system.

  vehicle, producing a high signal-to-noise ratio. Another object of the invention is to provide a microphone and its mount for use in a vehicle transmission system, having little tendency to be adversely affected by the noises of the wind, background or accessories of a vehicle with motor. The invention also relates to a microphone and its mount for a vehicle transmission system, which can be easily adjusted to be used by various different people in various different vehicles. Another object of the invention is to provide a car microphone and its mount, protected from mechanical vibrations of the vehicle, and a microphone and its

2 6 1 2 7 1 7

  mount for use in an automotive transmission system, which do not affect the mechanics of driving a car, such as shifting,

  steering wheel or safety restraint system.

  The invention also relates to a microphone and mount for use in a vehicle transmission system, which may be used with a conventional directional microphone, and a microphone and mount system for the microphone, which is a small system.

bulky and is discreet.

  These and other objects of the invention are obtained by means of a microphone and its mount,

  use with a transmission system for automobiles.

  The assembly formed by the microphone and its mount includes a mounting structure capable of receiving a microphone and means for attaching the mounting structure to a diagonal safety belt in an automobile. Means for fixing the mounting element to a belt

  diagonal advantageously allow a sliding movement

  the microphone and its mount to any position along the belt. In the preferred embodiment, the mount is used on the diagonal portion of a seat belt restraint system. In the preferred embodiment, too, the microphone cord is adapted to extend from the microphone hood, along the diagonal belt, to the winder on the door post of the automobile. or, in vehicles equipped with automatic reels of the diagonal belt, along the belt to its end piece on the seat. The preferred embodiment is further adapted to position a directional microphone to provide a signal-to-noise ratio of choice when used in the

  neighborhood of a clavicle of the driver of the vehicle.

  The invention will be described in more detail with reference to the appended drawings by way of non-limiting examples and in which the same reference numerals designate the same elements: FIG. 1 is a perspective view of the preferred embodiment of FIG. invention, mounted on a diagonal belt for automobile and used in an automobile; Figure 2 is an exploded perspective view of the preferred embodiment of the microphone and its mount, illustrating the assembly of the frame members; FIG. 3 is a top plan view of the inside of the preferred embodiment of the microphone mount, with the cover removed; FIG. 4 is a bottom view of the preferred embodiment of the hood of the microphone mount; Figure 5 is a bottom view of the preferred embodiment of the cover of the microphone mount, illustrating a windshield inserted into the hood; FIG. 6 is a side view of the upper structure of the frame of the preferred embodiment of the invention; Figure 7 is a front view of the upper frame structure shown in Figure 6; Figure 8 is a top view of the upper mounting structure shown in Figure 6; Fig. 9 is a top view of a lower frame structure, illustrating the arrangement of the invention for sliding the microphone mount on an automobile diagonal belt; Figure 10 is a side view of the structure shown in Figure 9; FIG. 11 is a front view of the structure illustrated in FIG. 9; FIG. 12 is a perspective view of another embodiment of the invention, showing the microphone and its mount configured to be used on a diagonal belt with automatic winding; Fig. 13 is a bottom perspective view of the embodiment of Fig. 12, illustrating the structure which prevents slippage along the belt; FIG. 14 is a diagram illustrating the

  polar response curve of the preferred form of

  measured at 1000 hertz; FIG. 15 is a perspective view of another variant of the invention, shown in use; Fig. 16 is a perspective view from above of the embodiment shown in Fig. 14; and - Figure 17 is a side view of the form

  embodiment illustrated in Figure 14.

  The preferred embodiment of the invention includes a microphone and mount adapted for use in an automotive transmission system, such as a cellular mobile telephone. The microphone and its mount are designed to be slidably mounted on the driver's diagonal belt, which belt is part of a conventional automobile restraint system. In the preferred embodiment, the microphone and its mount are designed to be used when they are approximately at the location of

the clavicle of the driver.

  The preferred embodiment of the invention is illustrated in FIG. 1. An assembly 10 is mounted on the diagonal retaining belt 12 forming part of a vehicle 13. The assembly is preferably placed along

2612 7 1 7

  the belt 12, in the vicinity of the clavicle of the driver of the motor vehicle, which allows the system to be used in a virtually optimal location for the reception of the sound and the minimization of the background noise. A spiral transmission cord 14 connects the assembly 10 to the transmission system by being fixed to the door upright 16 of the automobile. A non-spiraled portion 17 of the transmission cord follows the wand of the door jamb to the main electronics of the cellular telephone system. In the preferred embodiment, the assembly 10 is freely slidable on the belt 12 and is positioned by attaching the cord length to an anchor (not shown) on the door jamb. Figures 2 to 11 illustrate better the details of the preferred embodiment of the invention. With reference in particular to FIG. 2, the preferred embodiment of the assembly 10 comprises a base

  lower 18, an upper base 20 and a cover 22.

  A microphone cartridge 24 is fixed in the lower base 18. In the preferred embodiment,

  uses an electret and condenser microphone cartridge

  cardioid, with a diameter of 5.97 mm.

  As best seen in Figures 2, 3 and 9-11, the lower base is configured to receive the microphone cartridge 24. In the preferred embodiment, the lower base comprises a mounting plate 26 supported by two ends 28. To receive the microphone cartridge, the mounting plate 26 has a recess 30. In the preferred embodiment, the recess is rectangular, although other configurations are also appropriate, provided they are of a size that allows them to

  receive the microphone cartridge 24.

  To hold the microphone cartridge 24 in the recess 30, the latter has opposite rims 32 of support projecting from the recess. The cartridge 24 is fixed between the support flanges 32 by the tension of a foam block 31 surrounding it. In another embodiment, the cartridge is secured between the support flanges by two foam block segments 34, preferably formed of sections of a double adhesive foam. To facilitate manufacture, the base is made in two parts. Thus, the upper base 20 can be coupled with the lower base 18. The lower base preferably has end wings 36

  starting from the ends 28 of this lower base.

  The upper base itself has ends 38 which are aligned with the end wings 36. The upper base 20 also has an opening 40 whose size and shape correspond to a flange 42 of the lower base, surrounding the recess 30. When the upper and lower bases are assembled, the flange 42 enters the opening 40 to access the

microphone cartridge 24.

  The upper base 20 and the lower base

  18, in assembled configuration, also form an arrangement

  allowing a sliding movement of the assembly 10 on a diagonal safety belt. Thus, the preferred embodiment of the lower base comprises four fingers 44 running inwardly of the ends 28 of this base. As best illustrated in FIG. 6, the upper base 20 has double contact surfaces 46 and the lower base 18 has a corresponding lower contact surface. When the upper and lower bases are assembled in one piece, the surfaces 46 and 48 form a sliding surface for the diagonal belt. The remaining surface in contact with the diagonal belt is the upper face of the fingers 44. The use of fingers 44 allows easy positioning of the assembly 10 on a diagonal belt, the latter being simply folded so as to present a longitudinal fold to pass below the fingers 44. To reduce the amount of material used and increase the bending strength of the lower base, the latter has lower recesses 50. These are preferably formed during molding during of the production of the two base elements, usually in

plastic material.

  As best illustrated in Figures 2 and 3, the microphone cartridge includes a cord 52 leading from the cartridge to the outside of the assembly 10. The upper base 20 is configured to include a structure for fixing the cord 52 in the assembly by providing traction relief to prevent deterioration of the cartridge when the cord is stressed. In the preferred embodiment, the

  Microphone cartridge 24 includes lead wires 54.

  These conductive wires are connected to a connection pad 56 which is itself electrically connected to the cord 52. Although the connection pad 56 can be fixed to the upper base 20, in the preferred embodiment, it simply rests on the upper base and is held mainly in place by being fixed to the cord 52. The upper base 20 comprises

  two connecting columns 58.

  As best illustrated in Figures 2 and 4, the preferred embodiment of the assembly includes a cover 22 through slots 60 to allow sound to enter the assembly. In the preferred embodiment, the slots are positioned to form an angle with the longitudinal axis of the microphone cartridge 24. When the microphone is disposed with the slots inclined as shown in Fig. 1, the normal directional character of the microphone cartridge is then polarized slightly more

the mouth of the user.

  In the preferred embodiment, the slots are arranged to form an angle of about the longitudinal axis of the microphone cartridge 24. As illustrated in FIG. 14, the resulting polar pattern 62 for the directional microphone cartridge 24 is then rotated about 15 to the slots. The polar diagram shown in FIG. 14 is measured at 1000 hertz. It represents an approximate polar diagram for frequencies between about 300 and 2000 hertz. The line extending between the 0 and 180 degrees marks represents the axis of the microphone cartridge 24. The assembly 10 also comprises a windshield 62 inserted inside the cover 22. The windshield is preferably formed of a non-woven fabric material that is substantially sound-permeable, but has the ability to screen the wind. While it is possible to use a conventional rubber foam, the preferred embodiment uses a much thinner material known as "Viskon". Alternatively, the

  windshield can be formed of a fabric.

  The inside of the cover 22, as can be seen more clearly in FIGS. 4 and 5, comprises an earthing pin 66 and two screw bosses 68. In the preferred embodiment, the bosses are threaded with

  to receive screws 70. The bosses 68 are

  shown to correspond to screw holes 72 formed in the lower base 18 and 74 in the upper base 20. To obtain a smooth surface 48, the screw holes 72 of the lower base 18 each have a countersink 76 To establish the place for the tenon of

2 6 12 7 1 7

  the mass and screws, the shroud 62 is cut in a configuration such that it covers only part of the lid 22; any configuration is suitable provided that the windscreen completely covers the through slots

60.

  Assembly 10 also includes a damping

  In the preferred embodiment, the acoustic damper is preferably formed of a felt and is configured to have a

  microphone aperture 80 through which this damping

  acoustic son does not cover the plate 26 of mounting the lower base. Acoustic damper 78 occupies the space below the cover and to which slits 60 do not access, and it provides additional retention of lead wires 54, wafer 56 and cord 52. It also prevents these elements to move inside the assembly after the screws 70

have been totally fixed.

  The cover 22 of the assembly also has a recess 82 suitable for the introduction of a brand label or the like. In the preferred embodiment, the recess extends below the surface

  on the upper side of the lid 22.

  As illustrated in Figures 4 and 5, the cover 22 has two openings 84 for the cord, located in opposite sides of the cover. The upper base 20 comprises a corresponding pin 86 whose shape and size correspond to those of one of the openings. The use of two openings for the passage of the cord, associated with an upper base 20 which is separate from the lower base, allows the cord 52 to leave on one side or the other of the assembly by simply reversing the the upper base on 180 and set

  place the cord so that it goes to the other side.

  In each of the positions, the post 86 closes the opening

not used 84.

  Referring now to Figure 12, it further illustrates the general concept of the invention, as well as a variant of the installation mode. In Figure 12, there is shown a motor vehicle having a retractable diagonal belt 88. This diagonal belt is connected to a slider 90 mounted in a groove 92 extending approximately from the front of the driver's side window to the top In vehicles equipped with a retractable diagonal belt, the stopping of the motor implements a mechanism (not shown) which automatically moves the slider 90 forwards in the groove 92 and thus releases the occupying the belt. The lap belt 96 is removably connected to a loop (not shown) located on the

driver's side.

  To allow the use of the assembly 10 with an automatically retractable diagonal belt system as illustrated in FIG. 12, the assembly must be adapted so that the cord 52 is connected to a position other than the top of the door jamb. 94. When retractable diagonal belts are used, the assembly 10 is configured so that the bead 52 exits the opposite side of the cover 22 relative to

  to that shown in Figure 1, as previously described.

  The cord then descends along the diagonal belt and is connected to the lap belt near the seat between the driver and passenger positions. A non-spiraled portion 98 of the cord then extends to a cabinet 100 to electronics. The electronics cabinet contains all the necessary compounds at the interface of the microphone cartridge 24 with a conventional cellular telephone system. The electronics cabinet 100, in the embodiment of Figure 1 as in that of Figure 12, is mounted at any point and convenient inside the vehicle; for aesthetic reasons, the electronics cabinet 100 can be perfectly mounted

  outside the view, below the dashboard.

  In the embodiment of FIG. 1 (diagonal and ventral belts combined), the assembly is designed to slide along the diagonal belt 12. Thus, when the belt is retracted, the seat fastener of the assembly of Figure 1 (not shown) comes into contact with the microphone. The belt then slides between the finger 44 and the contact surface 46 and the microphone is placed between the clip of

  seat and anchorage of the belt on the door jamb.

  When the user initially enters the vehicle, he simply grasps the clip, moves it to pull the belt in front of his belly and chest, and snaps it into the seat provided in the corner of the seat. Friction and gravity lower the microphone and the voltage of the

  Spiral cord positions the microphone as shown.

  In the embodiment of Figure 12,

  the diagonal belt is never retracted and the

  appearance is then designed to prevent this movement of the belt. As best illustrated in FIG. 13, the movement is prevented by the use of a key 102

  slipped between the belt 88 and the contact surface 46.

  In the preferred embodiment, the key is made of a plastic material of the same type as that used for the upper and lower bases. However, any material reducing slippage of the belt 88 may be used. The embodiment of FIGS. 1 to 13 may also be embodied in the form of a structure constituting a "reflected image", having the same characteristics, but whose all positions are reversed. In such a configuration, the embodiment can be used appropriately in a right-hand drive vehicle, such as a postal vehicle or vehicles used in various foreign countries such as the United Kingdom. Referring now to Figures 15-17, another embodiment of the invention will be described using a removable microphone. In this variant of the invention, a second assembly 104 is attached to a diagonal safety belt system, generally in the same

  position with respect to the user than that of the

  In the same way as in the embodiment of the assembly 10, the electrical transmissions between the assembly and the electronics cabinet (not shown) are effected by means of a cord connected to the rod 16. the door amount. However, in the form

  embodiment shown in FIG. 15, the transmission

  The embodiment of the second assembly can also use a spiral cord, similar to that

  described as a piece of the preferred form of

tion.

  As illustrated more clearly in FIGS. 17, the second assembly 104 comprises an upper base 108 and a lower base 110 clamped on the diagonal safety belt 12. A conventional microphone 112 is removably attached to the upper base 108 by means of a mounting flange 114. The mounting flange may be of any configuration suitable for detachably holding a microphone; in the embodiment of Figures 15 to 17, the mounting is of the type described in US Patent No. 4,577,070. Alternatively, mounting flange 114 may be of a type which is attached

immovable way to a microphone.

  The embodiments of Figures 15 to 17 also include a clamping mechanism for securing the upper base 108 and the lower base 110 on the seat belt 12. Such a mechanism advantageously comprises screws 116 fixed through the base lower end 11O in tapped holes 118 formed in the upper base 108. The upper and lower bases are then clamped on the safety belt 12, making a friction fit with this belt and preventing assembly 104 to slide along

of the belt.

  Although variant embodiment 104 has mounting points which are manually positioned along the diagonal belt, other embodiments of the invention including the

  described above for the withdrawal and deployment of

  diagonal belt. The mechanism may also be adapted to place the microphone in a position approximately at the center of the occupant's chest (the position shown in Figure 15), when the diagonal belt is placed by the occupant, thereby ensuring that the microphone is relatively close to a

ideal location.

  As illustrated in FIG. 16, the position of the microphone 112 is advantageously such that the microphone is oriented towards the mouth of the user. In this way, a directional microphone can be used which minimizes noise from sources

  multiple sounds present in any vehicle running.

  It goes without saying that many modifications can be made to the microphone mount described

  and shown without departing from the scope of the invention.

Claims (18)

  A microphone mount for use with an automotive communication system, characterized in that it includes a mounting member having means for receiving a microphone (24) and means (10) for securing the mounting member. to a belt (12) of automobile safety.   The microphone mount of claim 1, wherein the means for attaching the mounting member to an automobile seat belt comprises means for sliding fastening so that the position of the mounting member on the seat belt can to be adjusted by sliding.   Microphone mount according to Claim 2, characterized in that the mounting element is connected to   a diagonal automobile safety belt.   Microphone mount according to claim 2, characterized in that the mounting element comprises a base (18) and one or more opposite sets of fingers (44) connected to and extending along the base. ci, and defining a belt retention zone between fingers and the base.   5. Microphone mount according to claim 4, characterized in that the mounting element further comprises means for preventing the belt from slipping. A microphone assembly for use in a car communication system, characterized in that it includes a diagonal belt mount (10), a microphone (24) connected to the mount, and a   cover (22) for the microphone, connected to the mount.   7. Microphone assembly according to the claim   6, characterized in that it further comprises a   windshield (62) covering the microphone.   8. Microphone assembly according to the claim   6, characterized in that the microphone cover further has one or more openings (60)   allowing the propagation of sounds towards the microphone.   9. Microphone assembly according to the claim   8, characterized in that the apertures are configured so as to directionally polarize the reception of sounds.   10. Microphone assembly according to the claim   9, characterized in that the openings are angled to optimize the reception of sounds when the   microphone rests on a clavicle of the user.   11. Microphone assembly according to the claim   10, characterized in that the microphone is directional and has an axis defining its main direction of sound reception, the openings comprising one or more household slots in the cover and   forming an angle with the microphone axis.   12. Assembly according to claim 6, characterized in that the mount can slide on the belt.   13. An assembly according to claim 6, characterized in that it comprises a microphone cord (52) which is designed to extend from the microphone cover to the top of the rod of a post. door (16) of an automobile.   14. A microphone mount of the type adapted to receive a portable microphone (112), characterized in that it is designed to be slidably attached to the diagonal belt (12) of a radio microphone system.   car seat belt.   15. Microphone mount according to the claim   14, characterized in that the microphone housing   is an integral part of the mount.   16. Microphone mount according to the claim   14, characterized in that the microphone constitutes a separate element of the mount and can be detached from the   mount to be used away from the diagonal strap.   17. Microphone mount according to the claim   15, characterized in that it includes a microphone cord (52) which is adapted to extend from the microphone mount to the top of a microphone rod. door (16) of automobile.   18. Microphone mount according to the claim   17, characterized in that it is also   shown to allow the microphone cord to extend from the mount to the binding of the belt with a car seat.