Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/02—Casings; Cabinets ; Supports therefor; Mountings therein
  • H04R1/028—Casings; Cabinets ; Supports therefor; Mountings therein associated with devices performing functions other than acoustics, e.g. electric candles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B42—BOOKBINDING; ALBUMS; FILES; SPECIAL PRINTED MATTER
  • B42D—BOOKS; BOOK COVERS; LOOSE LEAVES; PRINTED MATTER CHARACTERISED BY IDENTIFICATION OR SECURITY FEATURES; PRINTED MATTER OF SPECIAL FORMAT OR STYLE NOT OTHERWISE PROVIDED FOR; DEVICES FOR USE THEREWITH AND NOT OTHERWISE PROVIDED FOR; MOVABLE-STRIP WRITING OR READING APPARATUS
  • B42D15/00—Printed matter of special format or style not otherwise provided for
  • B42D15/02—Postcards; Greeting, menu, business or like cards; Letter cards or letter-sheets
  • B42D15/022—Postcards; Greeting, menu, business or like cards; Letter cards or letter-sheets combined with permanently fastened sound-producing or light-emitting means or carrying sound records
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
  • H04R7/00—Diaphragms for electromechanical transducers; Cones
  • H04R7/02—Diaphragms for electromechanical transducers; Cones characterised by the construction
  • H04R7/04—Plane diaphragms
  • H04R7/045—Plane diaphragms using the distributed mode principle, i.e. whereby the acoustic radiation is emanated from uniformly distributed free bending wave vibration induced in a stiff panel and not from pistonic motion

Definitions

• the invention relates to greetings or the like cards.
• a panel-form loudspeaker comprising:- a resonant multi-mode radiator element being a unitary sandwich panel formed of two skins of material with a spacing core of transverse cellular construction, wherein the panel is such as to have ratio of bending stiffness (B) , in all orientations, to the cube power of panel mass per unit surface area ( ⁇ ) of at least 10; a mounting means which supports the panel or attaches to it a supporting body, in a free undamped manner; and an electro-mechanical drive means coupled to the panel which serves to excite a multi-modal resonance in the radiator panel in response to an electrical input within a working frequency band for the loudspeaker.
• B bending stiffness
• ⁇ cube power of panel mass per unit surface area
• Embodiments of the present invention use members of nature, structure and configuration achievable generally and/or specifically by implementing teachings of our co ⁇ pending PCT application no. (our case P.5711) of even date herewith.
• Such members thus have capability to sustain and propagate input vibrational energy by bending waves in operative area(s) extending transversely of thickness often but not necessarily to edges of the member(s); are configured with or without anisotropy of bending stiffness to have resonant mode vibration components distributed over said area(s) beneficially for acoustic coupling with ambient air; and have predetermined preferential locations or sites within said area for transducer means, particularly operationally active or moving part(s) thereof effective in relation to acoustic vibrational activity in said area(s) and signals, usually electrical, corresponding to acoustic content of such vibrational activity.
• This invention is particularly concerned with greetings and the like cards incorporating acoustic devices e.g. in the form of loudspeakers.
• the term 'greetings card' is intended to encompass analogous cards such, for example as advent calendars and the like.
• the invention is a greetings or the like card, characterised by a board forming at least part of the card and in that the board is a distributed mode acoustic radiator having a transducer mounted wholly and exclusively on the radiator to vibrate the radiator to cause it to resonate.
• the board may be a panel having a cellular core sandwiched between skin layers.
• the board may comprise a core of foamed plastics sandwiched between sheets of craft board.
• the transducer may be a piezo-electric bender.
• the bender may be a crystalline member, e.g. a disc.
• the board may form a leaf of the card.
• the card may have a pair of leaves, and means associated with the leaves for triggering actuation of the radiator on movement of one leaf relative to the other leaf.
• the greetings or the like card may comprise a signal generator, an amplifier and an electric battery on a leaf of the card.
• Figure 1 is a diagram showing a distributed-mode loudspeaker as described and claimed in our co-pending International application No. (our case P.5711);
• Figure 2a. is a partial section on the line A-A of Figure 1;
• Figure 2b is an enlarged cross-section through a distributed mode radiator of the kind shown in Figure 2a. and showing two alternative constructions;
• Figure 3 is a perspective diagram of an embodiment of greetings card according to the present invention.
• Figure 4 is a perspective view of a transducer.
• FIG. 1 of the drawings there is shown a panel-form loudspeaker (81) of the kind described and claimed in our co-pending International application (our case P.5711) of even date herewith comprising a rectangular frame (1) carrying a resilient suspension (3) round its inner periphery which supports a distributed mode sound radiating panel (2).
• Figure 4 is mounted wholly and exclusively on or in the panel (2) at a predetermined location defined by dimensions x and y_, the position of which location is calculated as described in our co-pending International application (our case P.5711) of even date herewith, to launch bending waves into the panel to cause the panel to resonate to radiate an acoustic output.
• the transducer (9) is driven by a signal amplifier (10), e.g. an audio amplifier, connected to the transducer by conductors (28) .
• Figures 2a_ and 2b are partial typical cross-sections through the loudspeaker (81) of Figure 1.
• Figure 2a shows that the frame (1), surround (3) and panel (2) are connected together by respective adhesive-bonded joints (20) .
• Suitable materials for the frame include lightweight framing, e.g. picture framing of extruded metal e.g. aluminium alloy or plastics.
• Suitable surround materials include resilient materials such as foam rubber and foam plastics.
• Suitable adhesives for the joints (20) include epoxy, acrylic and cyano-acrylate etc. adhesives.
• Figure 2b illustrates, to an enlarged scale, that the panel (2) is a rigid lightweight panel having a core (22) e.g. of a rigid plastics foam (97) e.g. cross linked polyvinylchloride or a cellular matrix (98) i.e. a honeycomb matrix of metal foil, plastics or the like, with the cells extending transversely to the plane of the panel, and enclosed by opposed skins (21) e.g. of paper, card, plastics or metal foil or sheet. Where the skins are of plastics, they may be reinforced with fibres e.g. of carbon, glass, Kevlar or the like in a manner known per se to increase their modulus.
• a core e.g. of a rigid plastics foam (97) e.g. cross linked polyvinylchloride or a cellular matrix (98) i.e. a honeycomb matrix of metal foil, plastics or the like, with the cells extending transversely to the plane of the panel, and enclosed by
• Envisaged skin layer materials and reinforcements thus include carbon, glass, Kevlar (RTM), Nomex (RTM) i.e. aramid etc. fibres in various lays and weaves, as well as paper, bonded paper laminates, melamine, and various synthetic plastics films of high modulus, such as Mylar (RTM), Kaptan (RTM), polycarbonate, phenolic, polyester or related plastics, and fibre reinforced plastics, etc. and metal sheet or foil.
• Investigation of the Vectra grade of liquid crystal polymer thermoplastics shows that they may be useful for the injection moulding of ultra thin skins or shells of smaller size, say up to around 30cm diameter.
• Envisaged core layer materials include fabricated honeycombs or corrugations of aluminium alloy sheet or foil, or Kevlar (RTM) , Nomex (RTM) , plain or bonded papers, and various synthetic plastics films, as well as expanded or foamed plastics or pulp materials, even aerogel metals if of suitably low density.
• Some suitable core layer materials effectively exhibit usable self-skinning in their manufacture and/or otherwise have enough inherent stiffness for use without lamination between skin layers.
• a high performance cellular core material is known under the trade name 'Rohacell' which may be suitable as a radiator panel and which is without skins.
• the aim is for an overall lightness and stiffness suited to a particular purpose, specifically including optimising contributions from core and skin layers and transitions between them.
• the suspension (3) may damp the edges of the panel (2) to prevent excessive edge movement of the panel. Additionally or alternatively, further damping may be applied, e.g. as patches, bonded to the panel in selected positions to damp excessive movement to distribute resonance equally over the panel.
• the patches may be of bitumen-based material, as commonly used in conventional loudspeaker enclosures or may be of a resilient or rigid polymeric sheet material. Some materials, notably paper and card, and some cores may be self-damping. Where desired, the damping may be increased in the construction of the panels by employing resiliently setting, rather than rigid setting adhesives.
• Effective said selective damping includes specific application to the panel including its sheet material of means permanently associated therewith. Edges and corners can be particularly significant for dominant and less dispersed low frequency vibration modes of panels hereof. Edge-wise fixing of damping means can usefully lead to a panel with its said sheet material fully framed, though their corners can often be relatively free, say for desired extension to lower frequency operation. Attachment can be by adhesive or self-adhesive materials. Other forms of useful damping, particularly in terms of more subtle effects and/or mid- and higher frequencies can be by way of suitable mass or masses affixed to the sheet material at predetermined effective medial localised positions of said area.
• An acoustic panel as described above is bi ⁇ directional.
• the sound energy from the back is not strongly phase related to that from the front. Consequently there is the benefit of overall summation of acoustic power in the room, sound energy of uniform frequency distribution, reduced reflective and standing wave effects and with the advantage of superior reproduction of the natural space and ambience in the reproduced sound recordings.
• Figure 3 illustrates a greetings or the like card (144) incorporating loudspeaker technology of Figures 1 and 2.
• the card is in the form of a folded member having a front leaf (145) and a rear leaf (146).
• At least the rear leaf (146) is made from a composite board consisting of a core (22) of foam plastics sandwiched by skins of craft board (21) to form a rigid lightweight distributed mode acoustic radiator panel (2) of the kind described in Figures 1 and 2.
• Such composite boards are known under the trade name KAPPABOARD. It has been found that a panel shaped according to the European standard 'A' series is suitable.
• a transducer (9) as shown in Figure 4 is attached to the rear leaf (146) to vibrate the panel (2) to cause it to resonate to produce an acoustic output.
• the transducer (9) is driven by a signal generator/amplifier/ battery unit (112) which is actuated by a switch (53) concealed in the fold of the card so as to activate the signal generator when the card is opened.
• FIG 4 shows a transducer (9) for a distributed mode panel (2) in the form of a crystalline disc-like piezo bender (27) mounted on a disc (118), e.g. of brass, which is bonded to a face of the panel (2), e.g. by an adhesive bond (20) .
• a transducer (9) for a distributed mode panel (2) in the form of a crystalline disc-like piezo bender (27) mounted on a disc (118), e.g. of brass, which is bonded to a face of the panel (2), e.g. by an adhesive bond (20) .
• an acoustic signal applied to the transducer (9) via leads (28) will cause the piezo disc (27) to bend and thus locally resiliently deform the panel (2) to launch bending waves into the panel.

Landscapes

• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Acoustics & Sound (AREA)
• Signal Processing (AREA)
• Credit Cards Or The Like (AREA)
• Diaphragms For Electromechanical Transducers (AREA)
• Detergent Compositions (AREA)
• Fats And Perfumes (AREA)
• Medicinal Preparation (AREA)
• Cosmetics (AREA)
• Paper (AREA)
• Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
• Structure Of Receivers (AREA)
• Burglar Alarm Systems (AREA)
• Piezo-Electric Transducers For Audible Bands (AREA)
• Apparatuses For Generation Of Mechanical Vibrations (AREA)
• Respiratory Apparatuses And Protective Means (AREA)
• Lubricants (AREA)
• Polarising Elements (AREA)

Priority Applications (22)

Applications Claiming Priority (7)

Related Child Applications (1)

Publications (2)

Family

ID=34865236

Family Applications (1)

Country Status (20)

Cited By (21)

Families Citing this family (3)

Citations (7)

• 1996
  • 1996-09-02 HU HU9900177A patent/HUP9900177A3/hu unknown
  • 1996-09-02 RO RO98-00637A patent/RO119043B1/ro unknown
  • 1996-09-02 IL IL12348596A patent/IL123485A/xx not_active IP Right Cessation
  • 1996-09-02 SK SK265-98A patent/SK26598A3/sk unknown
  • 1996-09-02 EP EP96929389A patent/EP0847660B1/en not_active Expired - Lifetime
  • 1996-09-02 TR TR1998/00360T patent/TR199800360T1/xx unknown
  • 1996-09-02 AT AT96929389T patent/ATE177575T1/de not_active IP Right Cessation
  • 1996-09-02 NZ NZ316546A patent/NZ316546A/en unknown
  • 1996-09-02 WO PCT/GB1996/002144 patent/WO1997009841A2/en not_active Application Discontinuation
  • 1996-09-02 JP JP9510947A patent/JPH11512248A/ja active Pending
  • 1996-09-02 BR BR9610502-0A patent/BR9610502A/pt not_active Application Discontinuation
  • 1996-09-02 PL PL96325273A patent/PL182468B1/pl unknown
  • 1996-09-02 AU AU68804/96A patent/AU703015B2/en not_active Ceased
  • 1996-09-02 DE DE69601724T patent/DE69601724T2/de not_active Expired - Lifetime
  • 1996-09-02 EA EA199800258A patent/EA000859B1/ru not_active IP Right Cessation
  • 1996-09-02 DK DK96929389T patent/DK0847660T3/da active
  • 1996-09-02 CN CN96196704A patent/CN1195460A/zh active Pending
  • 1996-09-02 CZ CZ98584A patent/CZ58498A3/cs unknown
  • 1996-09-02 ES ES96929389T patent/ES2130847T3/es not_active Expired - Lifetime
• 1998
  • 1998-07-28 HK HK98109450A patent/HK1008596A1/xx not_active IP Right Cessation

Patent Citations (7)

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