RO119052B1 - Portable compact disk player - Google Patents

Abstract

The invention relates to a portable compact disc reader, comprising pair of opposing speakers (81), attached to the respective compact disc reader (41), each speaker (81) including an acoustic radiant element, on which it is integrally mounted. and exclusively, a translator (9), in order to produce the vibration of the radiant acoustic element and to cause its resonance. à

Description

The invention relates to a portable compact disc reader, and in particular, to such a compact disc reader such as those containing speakers provided with radiant acoustic elements, in the form of a panel.

It is known, from the patent application GB-A-2262861, the solution for making a panel-shaped speaker, comprising:

- a radiant element in various ways, resonant, in the form of sandwich panel, forming a unitary cellular construction consisting of two film layers of a material, separated by a core highlighted by the cross-section of the cell construction, the panel having, independently of steering, a coefficient of resistance to bending (B) equal to the mass of the panel at power 3, per unit of surface (μ), of minimum value 10;

- a mounting device that supports the panel or secures it to a support body, freely and without cushioning;

- an electromechanical actuator device, coupled to the panel and which is used to excite the resonant panel, radiant in various modes, in response to the application of an electrical signal corresponding to the working frequency band of the speaker.

US Patent 5-A-5349575, a GOLDSTAR CO application, discloses a compact disc reader comprising a slim body and a pair of removable articulated speakers on the body.

In order to achieve the present invention, elements of a certain type, structure and configuration are used, which can be obtained routinely and / or in particular, by applying the knowledge from the publication of the patent application PCT WO97 / 09842, whose applicant is the same as that of the patent. PCT patent application which was the basis for the opening of the national phase of this patent application. Such elements have the capacity to maintain and propagate, by means of flexural waves, vibration energy of entry, in the operational area or zones, which, as a rule, extend transversely on thickness, and not necessarily to the edges of the respective element or elements, being configured with or without anisotropy of flexural stiffness to have resonant type vibration components, advantageously distributed, in the respective or respective areas, for achieving acoustic coupling with the environment, having preferential locations or locations, predetermined, inside in that area, to dispose of a translator in the respective zone (s), in particular in that part or operationally active or mobile part thereof, effective in terms of acoustic vibration activity and in terms of electrical signals, as a rule, appropriate to the content acoustics of such activity v ibraţionale. In the publication of the mentioned PCT patent application WO97 / 09842, the uses of such elements are presented, within devices such as passive acoustic devices without a translator, such as, for example, for reverb, for acoustic filtration or for achieving acoustic harmony. in a space or in a room, and in acoustic devices active with the transducer, such as, for example, those in the very wide range of acoustic or speaker sources, when they are provided with input signals, to be converted respectively into beep, or such as, say, microphones, when exposed to a beep to be converted to another signal.

The present invention relates in particular to active acoustic devices, for example in the form of speakers for compact disc readers. In the following description and claims, it should be understood that the term compact disc is used with the intent to cover analogically encoded digital discs, such as digital video discs.

Elements of the above are known, such as, for example, radially distributed radiating elements, the characteristics of which are in accordance with the solution described in the aforementioned PCT patent application and / or in accordance with the specific features of the invention. from this description.

RO 119052 Β1

The object of the invention is a portable compact disc reader, characterized in that 50 comprises an opposite pair of panel-shaped speakers and that each speaker comprises a rigid, lightweight element having the ability to maintain and propagate, through bending waves. , vibrational input energy, in at least one active area that extends transversely on thickness, to have resonant type vibrational components, distributed over the respective area, and to have preferential locations or locations, predetermined, within that zone, for arranging in one of the respective sites or locations, a transducer mounted integrally and exclusively, on said radiant element, to determine the vibration of said radiant element, so that it enters the resonance, thus forming an acoustic emitter which generates a radiation acoustic when it resonates. The portable compact disc reader can comprise a portion of the body provided with a tray and a cover 60 that can be closed over the tray, and the speakers can be mounted on the cover. Thus, the speakers can be hinged to the lid. Alternatively, the speakers may each be inserted into a slot of the lid and may have a sliding motion between a retraction position, where the speakers are substantially, fully inserted into the slot, and a position of use, in which the speakers are positioned on opposite sides of the lid. Each radiator may comprise a lightweight rigid panel having a cellular core disposed between two film layers. The radiator can be supported in a frame that surrounds them. Elastic suspension means may be interposed between the frame and the radiant element.

The compact disc reader, according to the invention, has the advantage of using within its composition a panel-shaped element, thus acquiring all the advantages 70 related to it:

- has a simple, lightweight construction;

- it is easy to make and integrate within a compact disc reader;

- allows to obtain a uniform distribution of the resonance throughout the panel. 75 below is an example of an embodiment of the invention, in connection with FIGS.

- Fig. 1, constructive diagram of a distributed type diffuser, according to the description of the invention in the publication of PCT patent application WO97 / 09842;

- Fig. 2a, view through a partial cross-section, along the section line A-A 80 of Fig. 1;

- Fig. 2b, view through a cross-section, on an enlarged scale, of a radiant element with a distributed operation, of the type of the one in fig. 2a, presented in two embodiments;

- Fig. 3, perspective view of a portable compact disc reader, which is in 85 closed position (storage), according to a first embodiment;

FIG. 4 is a perspective view of the compact disc reader in FIG. 3 which is in the open position (for use);

FIG. 5 is a detail view of a portion of the compact disc reader in FIG. 3 and 4;

6 is a perspective view of a portable compact disc reader, in accordance with a second embodiment 90;

FIG. 7 is a detailed view of a portion of the compact disc reader of FIG. 6.

Figure 1 shows a panel-shaped speaker 81, of the type described in PCT patent application publication WO97 / 09842, whose applicant is the same as the PCT patent application that was the basis for opening the national phase of the present application. patent, diffuser 95, 81, having a rectangular frame 1, of which elastic suspension means 3 are fixed, arranged around its internal peripheral contour, supporting a

RO 119052 Β1 radiant element 2, acoustic, in panel form, of distributed type (with distributed operation). A translator 9, for example of the type that is widely presented in PCT patent application publications WO97 / 09859, WO97 / 09861, WO97 / 09859 having the same date and the same applicant as the PCT patent application, is mounted entirely and exclusively on, or within the radiant element 2, in the form of a panel, in a predetermined location, defined by the x and y coordinates, and whose location is calculated according to those presented in the publication of the PCT patent application W097 / 09842, mentioned above, in the purpose of producing, in the panel, a bending wave that causes its resonance to enter, in order to generate an acoustic output emission.

The transducer 9 is controlled by a signal amplifier 10, for example, an audio frequency amplifier connected to the transducer by means of conductors 28. The signal amplifier load 10 and the power requirement may be the normal ones, similar to those of conventional conical speakers, and the sensitivity is of the order of 86 ... 88 dB / watt when used in a furnished room. The load impedance of the signal amplifier 10 is largely resistive, being 6 ohms, which dissipates a power of 20 ... 80 watts. When the core and / or the film layers of the panel are metallic, they can be made to act as a heat radiator of the transducer, to evacuate the heat from the coil of the coil-motor assembly of the transducer and thus improve the energy balance. .

Figure 2a and 2b show partial cross-sections, typical for the speaker 81 of Figure 1. in FIG. 2a shows how the frame 1, the elastic suspension means 3 and the radiant element 1 in the form of a panel, are connected together, using some adhesive jointing means 20. As suitable materials for the realization of the frame 1 we mention the light frame type structures. painting made of extruded metal, aluminum or plastic alloy. For elastic suspension means 3 it is advisable to use elastic materials such as, for example, rubber or plastic, both of foam type. As suitable materials for adhesive bonding means 20, we mention epoxy, acrylic, cyanoacrylate adhesives etc.

Figure 2b shows, on a larger scale, the radiant element 2, in the form of a lightweight, rigid panel, comprising a core 22, made of a rigid foam 97, made of plastic, such as, for example, chloride of crosslinked polyvinyl or a cell matrix 98, having a honeycomb structure made of metal foil, plastic or other similar material, and whose cells are arranged transversely, in relation to the plane of the panel, being closed by two layers of film. 21, opposite, made, for example, of paper, cardboard, plastic or sheet or sheet metal. When the film layers 21 are plastic, for growth of its (Young's) module, they may be fiber reinforced, in a manner known per se, the fibers being, for example, carbon, glass, Kevlar® or the like.

The materials proposed for making the coating and curing film states include carbon, glass, Kevlar®, Nomex® meaning aramid fibers, etc., of different structures and textures, such as paper, laminated pressed paper, melamine and various films. made of high-modulus (Young) synthetic plastics, such as Mylar®, Kaptan®, polycarbonate, phenol, polyester or associated plastics, and fiber-reinforced plastics, etc., and foils and sheets. The studies and researches carried out on the Vectra class of polymeric thermoplastic materials with liquid crystals have shown that they can be used with good results for the injection molding of the coating film layers or of the ultrathin coatings of relatively small size, for example with diameters up to about 30 cm. This material itself forms a structure with crystals oriented in the direction of injection, offering a preferential orientation for better propagation of acute energy, from the point of action to the edges of the panel.

In addition, such a technique for forming thermoplastics of the aforementioned or other types allows the assembly of forming machines to transport positioning and centering pieces, such as, for example, grooves or rings for precise placement of the transducer component parts, such as the motor coil assembly and the non-magnetic suspension. Moreover, for some types of materials, less resistant, used when making the core, it is considered that it would be advantageous to increase locally, up to 150% of the diameter of the translator, the thickness of the covering film state, for example on a portion or on circular surface, in order to increase the resistance of the respective portion or surfaces and to advantageously couple the vibrational energy in the panel. In this way, by using softer sponge materials, the high-frequency response is improved.

The materials used to make the core used as a core are honeycomb shaped or have a corrugated appearance, being made from sheets or sheets made from aluminum alloys or Kevlar®, Nomex®, plain or pressed paper, and from different types of layers. films made of synthetic plastics, such as expanded or 160 foam plastics, or even pastes, including metal aerogels, if they are of sufficiently low density. Some of the materials suitable for making the core used as a core have practically the property of automatically forming their coating film states at the time of manufacture and / or may have an inherent rigidity sufficient to be used between the coating film layers without require rolling. Another material, which can be used to make the core used as the core and having the trade name 'Rohacell', is known for its high performance, being of the type without a covering film layer, the material being used as a radiant panel. Basically, the aim is to obtain a material of low weight and overall rigidity corresponding to a particular application, assuming including the optimization especially of the layers 170 used as core, of the covering film layers and of the portions between them.

Some of the preferred embodiments of such a panel use metal sheets or sheets of metal alloys, or as an alternative, use a carbon fiber reinforcement. Both of the above solutions, as well as other metal honeycomb structures or 175 aerogels (Kevlar and carbon alloys), used as a core, have special radio frequency shielding properties, which is of particular importance in different EMC applications. Conical type speakers or conventional panels do not have such inherent EMC shielding properties.

In addition, it should be taken into account that in the preferred embodiments 180 of the invention, piezoelectric and electrodynamic transducers have electromagnetic radiation or magnetic fields of dispersion, of negligible intensities. Conventional loudspeakers have large magnetic fields, which can be up to one meter apart, unless specific countermeasures are taken.

In the case of applications where good shielding is required, the electrical connections 185 may be made to the electrically conductive parts of a corresponding type DML panel or to an electrically conductive foam, or it may be resorted to using an interface, similar to those used in mounting. edges.

The elastic suspension means 3 provide the damping of the edges of the panel 2 to prevent excessive displacement of the edges of the respective panel. In addition or as a displacement variant 190, it can also be used as a damping, for example applying patches fixed to the panel in certain preselected positions to mitigate excessive movements in order to ensure uniform distribution of the resonance throughout. panel. Such patches can be made from material made of bitumen, usually used in conventional speaker enclosures, or can be made of a polymeric, laminated material, 195

RO 119052 Β1 elastic or rigid. Some materials, especially paper and cardboard, as well as some materials used as a core, may exhibit self-attenuation properties. When desired, when making the panel, the damping can be increased by using adhesives whose hardening is elastic, instead of using some rigid hardening.

A selective and efficient cushioning implies a specific application on the panel and also on the laminated material which is an integral, permanent part thereof. The edges and corners may prove particularly important for low frequency vibration modes of the panels, which are dominant and of lower dispersion. Fixing the edges, for a cushioning element, can usefully lead to obtaining a panel whose material, in laminated form, is completely trapped on the edges, even though its corners will remain relatively free, for example to allow for possible extension of operation at relatively low frequencies. The fixing can be done with the help of adhesive or even self-adhesive materials. Other useful forms of depreciation, especially when pursuing certain special effects and / or medium and high frequencies, may be in the form of one or more appropriate weights, fixed by the laminated material in certain predetermined positions, practically located medially within the respective area.

An acoustic panel of the type described above is bidirectional. The energy of the sound coming from the rear speaker is not very correlated with that of the sound coming from the front speaker. consequently, the advantage of a global summation of the acoustic power in the room is obtained, a uniformly distributed sound energy in terms of frequencies, reduced stationary wave effects and with the advantage of better reproduction, in the reproduction of sound, space and environment. naturally registered.

If the radiation emitted by an acoustic panel is largely non-directional, however, it must be taken into account that the percentage of acoustic information correlation increases outside the axis. For a better focus on artificially created stereo images, the layout of the speakers, as well as the images, at the height of a person standing has the advantage of an easy off-axis position for listeners who are usually seated, which leads to optimization of the stereo effect. In the same way, the left / right triangular geometry that includes the listener provides an additional angular component. In this way, a good stereo effect can be obtained.

For a group of listeners there is an advantage, compared to playing using a conventional speaker. By the nature of dispersion that intrinsically characterizes the sound emission made by the acoustic panel, a volume of sound is produced that does not satisfy the dependence law inversely proportional to the square of the distance, for an equivalent point source. Due to the fact that the intensity reduction with the distance is much smaller than the one determined by applying the dependence law inversely proportional to the square of the distance, it will result that for the non-centrally located listeners, who occupy disadvantaged places, the intensity of the field for the panel type speaker will produce a stereophonic effect. superior to that of conventional speakers. This is because the non-centrally located listener is no longer subject to double shortcomings due to the proximity to the speaker in the immediate vicinity: first, the excessive increase in the volume of the speaker located nearby, and secondly, the corresponding reduction in volume for the speaker further away. .

There is also the advantage of a flat panel, low weight, nice looking, good looking sound quality speaker, requiring only a translator, without producing sound translations for a whole range of sounds from each diaphragm of the panel.

RO 119052 Β1

245 in FIG. 3 ... 6 there is presented a portable personal compact disc reader 41, of the type provided with a body 85, which has a slot 82, through which the discs can be loaded and removed, and some control buttons 137, through which the reader is operated. The reader 41 is provided with speakers 81, pair, opposed in the form of thin panel elements 40 hinged on the opposite sides of the reader 41 to flank it. The speakers 40 are sized so that they come in the extension of the reader and can be articulated from the closed position, represented in fig. 3 in the extended position represented in fig. 4, as indicated by the arrow Ό. In the extended position, the reader body 85 tends to act as a central buffer, which separates the speakers 40 to improve channel separation.

Each of the panel-shaped speakers 40 is in the form of a distributed-mode acoustic radiator, of the type described above with reference to Figs. 1 and 2. Thus, each speaker comprises a panel-shaped, rigid, lightweight acoustic transmitter 2. , formed of a cell core 22, comprised between film layers 21, the panel being mounted in an elastic suspension 3, which surrounds it, for example from the rubber foam, which is mounted in a rectangular, light frame 1 , for example from plastic. A transducer 9, for example as described in PCT patent publications W097 / 09859, W097 / 09861, W097 / 09858, is attached to each acoustic transmitter 2, in the form of a panel, to produce transverse waves inside the panel in order to cause the panel to resonate and produce an acoustic output size. The transducer 9 is disposed on the respective acoustic transmitters 2, in panel form, in predetermined positions, as shown in the publication of the PCT patent application WO97 / 09842, mentioned.

Fig. 6 and 7 illustrate a portable compact disc reader 41, of the type comprising a body 85, which supports a tray 86, control knobs 137 and a lid 139, hinged as indicated by the arrow D, to be closed on above the plate.

The reader 41 is provided with speakers 81, pair, opposed in the form of thin panel elements, which, as shown 40, can be hinged by the sides of the lid 139, so that they can move as indicated by the arrow Έ from - a closed position (not shown) in the represented position represented. Alternatively, as shown by the panel speakers 39, 81 may enter a slot (not shown) in the cover 139 and may slide as indicated by the arrow 'F' between the extended and retracted positions.

Each of the panel speakers 39, 40 is in the form of an acoustic radiator distributed in a manner similar to that described above with reference to FIG. 1 and 2. Thus, each diffuser comprises a rigid, lightweight panel 2 formed by a cell core 22, comprised between covers 21, the panel being mounted in an elastic suspension 3, which surrounds them, for example by rubber foam, which is mounted in a light rectangular frame 1, for example plastic. A transducer 9, for example as described with respect to the aforementioned international publications WO97 / 09859, W097 / 09861, W097 / 09858, is attached to each acoustic transmitter panel 2, to produce bending waves inside the panel to cause entry in the resonance of the panel and produces an acoustic output size The transducer 9 is disposed on the respective acoustic transmitters panels 2 in predetermined positions, as shown in the publication of PCT patent application W097 / 09842.

Claims (7)

claims 1. Portable compact disc reader, characterized in that the respective compact disc reader (41) comprises opposing, pair-type speakers (81) made in the form of a panel, which are fixed by the reader (41), each of which the two speakers (81) comprising a 250 255 260 265 270 275 280 285 RO 119052 Β1 radiant element having the capacity to maintain and propagate, by means of flexural waves, vibrational input energy, in at least one active zone that extends transversely on thickness, to have vibrational components of resonant type distributed in the respective area, and in order to have preferential locations or locations, predetermined, within that area, to dispose, in one of those places or locations, of a transducer (9) mounted integrally and exclusively on said radiant element, to determine the vibration of said radiant element, thus so that it enters the resonance, thus forming an acoustic transmitter (2) that generates an acoustic radiation when it resonates. Compact disc reader according to claim 1, characterized in that said compact disc reader (41) comprises a portion (85) provided with a rotary plate (86) and a cover (139) adapted both to fit closes on the rotary plate (86) as well as for mounting on the cover (139) of the speakers (81). Compact disc reader according to claim 2, characterized in that the speakers (81) are connected by lid joints (139). Compact disc reader according to claim 2, characterized in that the speakers (81) are housed in a slot of the lid for performing a sliding motion between a clamping position, wherein the speakers (81) are practically completely housed. in the slot, and a position for use in which the speakers (81) are positioned on the opposite, opposite sides of the lid (139). 5. Compact disc reader according to any one of the preceding claims, characterized in that the acoustic transmitter (2) for each of the two speakers (81) comprises a panel, light and rigid, having a cell core (22) interspersed between layers. (21) opposite. Compact disc reader according to claim 5, characterized in that the acoustic transmitter (2) is supported by a frame (1) surrounding it. Compact disc reader according to claim 6, characterized in that said compact disc reader (41) comprises elastic suspension means (3) interposed between the frame (1) and the acoustic transmitter (2).