JP6516703B2 - Ceiling speaker - Google Patents

Description

  The present invention relates to a ceiling speaker, and in particular, it is installed on the back side of a ceiling plate such that the sound emitting surface of the speaker unit is exposed to the front side of the ceiling plate via a mounting hole provided in the ceiling plate. The present invention relates to a so-called separate-type ceiling speaker in which a panel is attached on the surface side of the ceiling plate to cover the sound emitting surface of the speaker unit together with the mounting holes.

  As a ceiling speaker of this type, there is one conventionally disclosed in, for example, Non-Patent Document 1. Referring to FIGS. 23 and 24, this conventional ceiling speaker 1 is provided with a dynamic speaker unit 2. The speaker unit 2 is housed in a hard resin case 3 as a housing together with other parts such as a matching transformer (not shown). The case 3 includes a substantially rectangular flat base 3a on which the components including the speaker unit 2 are mounted, and a cover 3b covering the components mounted on the base 3a. The base 3a is provided with a circular opening hole 3c for exposing the sound emitting surface (diaphragm) 2a of the speaker unit 2 to the outside of the base 3a (case 3). The opening 3c is provided such that its center is located at the center in the lateral direction of the base 3a, and the center is located slightly closer to the end edge than the center in the longitudinal direction of the base 3a. . Furthermore, in the opening hole 3c, a protective web 3d in the form of a substantially spider web for protecting the sound emitting surface 2a of the speaker unit 2 is provided. Further, in the protective strip 3d, a portion 3e passing through the center of the opening 3c and extending along the longitudinal direction of the base 3a has an appropriate dimension in the thickness direction of the base 3a. It also functions as a rib for improving the mechanical strength of the base 3a.

  On the other hand, the cover 3 b has a portion 3 f formed in a roughly dome shape to cover the speaker unit 2. In the outer surface of the dome-like portion 3f, a substantially concave elongated restraint groove 3g for restraining a spring coil 5 as an elastic elastic body used for attaching a panel 4 to be described later is included in the dome-like portion 3f. It passes along the top and is provided along the longitudinal direction of the case 3 (base 3a). At the same time, a pair of through holes 3h and 3i through which both ends of the spring coil 5 are individually inserted are provided in the vicinity of the portions of the cover 3 that correspond to the both ends of the restraining groove 3g. Further, a similar pair of through holes 3j and 3k are provided in portions of the base 3a corresponding to the through holes 3h and 3i. Further, the portion 3n of the cover 3b opposite to the side where the dome shaped portion 3f is provided in the longitudinal direction of the case 3 is formed in a substantially rectangular parallelepiped shape. The rectangular parallelepiped portion 3n is formed in a substantially rectangular parallelepiped shape in order to cover the above-mentioned matching transformer. In addition to the matching transformer, an autotransformer for an attenuator (volume regulator) may be provided, and the autotransformer in this case is also accommodated in the rectangular parallelepiped portion 3n. In addition, two terminal blocks 6 and 7 to which appropriate wires (cables) are connected are provided in the rectangular parallelepiped portion 3 n in a state of being exposed to the outside.

  The ceiling speaker 1 configured as described above is installed in the following manner. First, appropriate wires are connected to the two terminal blocks 6 and 7. Then, as shown by an arrow 3p in FIG. 25 (a), from the front surface side of the ceiling plate 8 to the back surface side of the ceiling plate 8 via the circular attachment holes 8a provided in the ceiling plate 8. That is, the ceiling speaker 1 is inserted into the ceiling. At this time, the ceiling speaker 1 is inserted into the mounting hole 8a from the end side (the rectangular parallelepiped portion 3n side) where the two terminal blocks 6 and 7 are provided. Then, as shown in FIG. 25 (b), the ceiling speaker 1 is placed behind the ceiling so that the sound emitting surface 2a of the speaker unit 2 of the ceiling speaker 1 is exposed to the surface side of the ceiling plate 8 through the mounting hole 8a. Placed in In this state, as shown by the arrow 5a in FIG. 25 (c), the hooks 5b and 5b provided at both ends of the spring coil 5 correspond to the corresponding hook locking portions 4a of the substantially disk-like panel 4 and It is locked to 4a. Thereby, the panel 4 is drawn to the ceiling speaker 1, and the panel 4 is attached to the ceiling speaker 1 (housing 3) by a so-called spring catch method. Then, the sound emitting surface 2 a of the speaker unit 2 is covered with the mounting hole 8 a by the panel 4. Thus, a series of installation work of the ceiling speaker 1 including the panel 4 is completed. The ceiling speaker 1 is fixed in a state in which the ceiling plate 8 is held in cooperation with the panel 4 by the elastic force of the spring coil 5, but if necessary, the ceiling plate 8 is a suitable fixing member such as a screw. It may be fixed.

TOA Corporation, Internet website, product information, ceiling speaker "CM-1830A" and "CM-1830AT", [June 7, 2016 search], URL: http://www.toa.co.jp/products/ prosound / speakers / speakers_ceiling / cm-1830a.htm, http://www.toa.co.jp/products/prosound/speakers/speakers_ceiling/cm-18030at.htm product information JP-A-9-331596

  By the way, this conventional ceiling speaker 1 adopts the speaker unit 2 whose aperture (of the sound emitting surface 2a) is about 120 mm. Therefore, for example, assuming that the longitudinal direction of the case 3 (base 3a) of the ceiling speaker 1 is the longitudinal direction of the ceiling speaker 1, the dimension L 'in the longitudinal direction of the ceiling speaker 1 is L' = It is 215 mm. Further, assuming that the short direction of the case 3 of the ceiling speaker 1 is the width direction of the ceiling speaker 1, the dimension W ′ in the width direction of the ceiling speaker 1 is W ′ = 134 mm. Furthermore, assuming that the direction perpendicular to each of the longitudinal direction and the width direction of the ceiling speaker 1 is the height direction of the ceiling speaker 1, the dimension H 'in the height direction of the ceiling speaker 1 is H' = It is 80 mm. In order for the ceiling speaker 1 of such a size to be installed on the ceiling in the above manner, the opening diameter ’′ of the mounting hole 8 a provided in the ceiling plate 8 needs to be at least’ ′ = 150 mm. The upper limit of the opening Φ ′ is suitably about 160 mm. Furthermore, the height dimension of the ceiling and the ceiling, that is, the depth dimension A ', is required to be A' = 130 mm or more. Further, as the panel 4, one having an outer diameter B 'of B' = 180 mm is adopted.

  That is, when the state where the conventional ceiling speaker 1 including the panel 4 is installed is viewed from the surface side of the ceiling plate 8, the speaker having the panel 4 with the outer diameter B ′ of B ′ = 180 mm is embedded in the ceiling plate 8 It looks like it's Thus, the design of the indoor space including the ceiling plate 8 to which the panel 4 is attached is maintained. On the other hand, in the same space (the ceiling plate 8), for example, a downlight or a ceiling-embedded emergency lighting device may be installed. In recent downlights and ceiling-embedded emergency lighting devices, the opening diameter of the mounting hole is 100 mm, and many of them have a size corresponding to the opening diameter. When the conventional ceiling speaker 1 is installed in the same space as such a downlight or emergency lighting device, the size of the panel 4 corresponding to the appearance of the conventional ceiling speaker 1 is outstanding compared to the downlight or emergency lighting device. As a result, there is a problem that the design of the space is impaired by this. Therefore, from the market, miniaturization of ceiling speakers including panels is required. Also, for example, if the opening diameter of the mounting hole required for installing the ceiling speaker is the same as the opening diameter of the mounting hole required for installing the downlight or the emergency lighting fixture, that is, 100 mm, these mounting holes The work efficiency at the time of installation can be improved. Also from this, the miniaturization of the ceiling speaker including the panel is required. In addition, if miniaturization of the ceiling speaker is realized, installation under circumstances where the depth size of the ceiling is even smaller becomes possible, and market expansion is expected.

  Then, an object of the present invention is to provide a ceiling speaker smaller than before.

According to the present invention, the sound emitting surface of the speaker unit is exposed to the surface side of the ceiling plate by being inserted to the back side of the ceiling plate through the mounting hole provided in the ceiling plate. The ceiling speaker installed on the back side is assumed. Under this premise, it is possible to provide a housing that accommodates a plurality of component elements including the speaker unit. The housing is a base on which the component element is mounted, and the base is mounted on the back surface side of the ceiling plate so as to straddle the mounting hole, and a cover which covers the component element mounted on the base Contains. The dimensions of the housing in a first direction orthogonal to the central axis of the sound emitting surface of the speaker unit are the dimensions of the housing in a second direction orthogonal to the central axis of the sound emitting surface and the first direction, respectively. Too big. The plurality of component elements include the speaker unit, and the first electric component and the second electricity both have smaller dimensions in the second direction and smaller dimensions in a direction along the central axis of the sound emitting surface than the speaker unit. Parts are included. The speaker unit is disposed on the base substantially at the center in each of the first direction and the second direction. A first electric component is disposed in a first virtual plane defined between one end of the base in the first direction and the speaker unit, and between the other end of the base in the first direction and the speaker unit By arranging the second electric component in the second virtual plane defined by the above, the cover can be formed in a substantially frustum shape.

  That is, according to the present invention, the plurality of component elements including the speaker unit are accommodated in the housing. Here, for example, it is assumed that the first direction is the length direction of the housing, and the second direction is the width direction of the housing. Then, it is assumed that the direction orthogonal to each of the first direction and the second direction, that is, the direction along the central axis of the sound emitting surface of the speaker unit is the height direction of the housing. Furthermore, among the component elements including the speaker unit, the first specific element having the largest dimension in the height direction of the housing, that is, the height dimension, is approximately the center in the longitudinal direction and the width direction in the housing. Located in Then, on a virtual plane that includes the central axis of the radiation surface of the speaker unit and extends along the length direction, a second specific element other than the first specific element of the respective component elements is located. As a result, for example, the outer shape of the housing can be formed so as to have a generally frustum shape (in other words, a mountain shape). In other words, each component can be accommodated in the roughly frustum shape housing. As described above, the outer shape of the housing is roughly frustum shaped, so that the size of the ceiling speaker can be reduced, and the installation work of the ceiling speaker through the mounting hole can be facilitated. Then, the opening diameter of the mounting hole can be reduced, and the depth dimension of the ceiling under which the ceiling speaker can be installed can be reduced.

The first electrical component may be a matching transformer, and the second electrical component may be an attenuator transformer.

The cover can also be formed into a generally square frustum with the portion covering the speaker unit as the upper base and the base as the lower base. Furthermore, in the inclined surface connecting the upper bottom and the lower bottom, the cover covering the first electric component and the second electric component in a portion covering the first electric component and the second electric component. Can be formed into a substantially rectangular parallelepiped shape.

In the present invention, the sound emitting surface of the speaker unit may be covered by the panel together with the mounting hole on the surface side of the ceiling plate. The panel is drawn to the housing by a substantially linear elastic member and attached to the ceiling speaker (housing). To that end, the housing is provided with a pair of through holes through which the elastic elastic body is inserted. One of the pair of through holes is a position between the first virtual plane and the speaker unit, and is provided on one end side of the casing in the second direction, and the other of the pair of through holes is A position between the second virtual plane and the speaker unit is provided on the other end side of the housing in the second direction.

  Furthermore, one of the pair of through holes may be provided at one end side of the housing in the width direction of the housing at a position deviated from the first virtual plane described above. The other through hole may be provided at the other end side of the housing in the width direction of the housing at a position deviated from the above-described second virtual plane.

  By the way, an opening hole for exposing the sound emitting surface of the speaker unit to the outside of the housing is formed in the housing. Then, a projecting wall is provided along a part or all of the periphery of the opening, and protrudes toward the outside of the housing along a direction along the central axis of the sound emitting surface of the speaker unit, It may be provided. By providing such a projecting wall, in the case where the above-mentioned pair of through holes are provided, in particular, through the portion other than the opening hole, the antiphase sound emitted from the back side of the sound emitting surface of the speaker unit In this case, the disadvantage that the sound emitted from the sound emitting surface is canceled by being wound around the sound emitting surface side of the speaker unit via the pair of through holes is suppressed. Thereby, the sound quality can be improved.

  In addition, the portion of the housing facing the back surface of the ceiling plate is provided at a position outward of the periphery of the sound emitting surface in the radial direction of the central axis of the sound emitting surface of the speaker unit, and the sound emitting A protrusion may be further provided which protrudes toward the outside of the housing along the direction along the central axis of the surface. That is, according to the present invention, the opening diameter of the mounting hole can be reduced as described above, but the ceiling speaker of the present invention may be installed as a substitute for the conventional ceiling speaker 1, for example, It may be installed at a place where an installation hole larger than the necessary diameter of 150 mm is provided. In this case, depending on the installation situation of the ceiling speaker of the present invention, there is a concern that the ceiling speaker may slip through the mounting hole and fall. In order to avoid this, the projections referred to here are provided. That is, when the projection engages with the mounting hole, the ceiling speaker of the present invention is prevented from falling through the mounting hole.

  Moreover, the middle in the length direction of the case may be narrowed inside the case in the width direction of the case among the portions of the case facing the back surface of the ceiling plate. In other words, the width dimension of the housing may be narrowed midway in the longitudinal direction of the housing. By providing such a constriction, the installation work on the ceiling through the mounting hole of the ceiling speaker of the present invention can be facilitated. This also greatly contributes to the reduction of the opening diameter of the mounting hole, and also contributes to the reduction of the depth dimension of the ceiling under which the ceiling speaker can be installed.

  Furthermore, in the present invention, a first terminal block and a second terminal block may be provided. The first terminal block among them is a first normal terminal group including a plurality of first normal terminals, a first emergency terminal group including a plurality of first emergency terminals, and a common terminal group including a plurality of common terminals; Have. The second terminal block includes at least one second normal terminal interconnected with the first normal terminal group, and at least one second emergency terminal interconnected with the first emergency terminal group. And a speaker input terminal group including a plurality of speaker input terminals. In addition to this, there may be provided switching means for selectively switching between the state in which the first normal terminal group and the speaker input terminal group are connected to each other and the state in which the first normal terminal group and the speaker input terminal group are not connected. And one side of a pair of input terminals of a speaker unit, for example, an anode input terminal, shall be connected to a speaker input terminal group. Further, it is assumed that the other of the pair of input terminals of the speaker unit, for example, the cathode input terminal is connected to the common terminal group. According to this configuration, the connection with the external attenuator is particularly simplified as will be described later, and the connection when the crossover wiring is provided is also simplified.

  The above-mentioned first specific element in the present invention is, for example, a speaker. The above-mentioned second specific element includes, for example, a matching transformer connected to the speaker unit. In this case, the matching transformer is arranged on either the first virtual plane or the second virtual plane described above.

  As described above, according to the present invention, it is possible to provide a ceiling speaker that is smaller than the conventional one. Thereby, when the ceiling speaker of this invention is installed in a ceiling board, especially the design property of the indoor space containing the said ceiling when a panel is attached improves rather than before. Further, for example, the opening diameter of the mounting holes provided in the ceiling plate can be made the same as the opening diameter of the mounting holes required for the installation of recent downlights and emergency lighting fixtures. Efficiency can be improved. Furthermore, since the installation under a situation where the depth size of the ceiling is smaller than before is possible, market expansion is expected.

It is a perspective view by CG of the ceiling speaker which concerns on one Embodiment of this invention. It is the perspective view by CG from the direction different from FIG. It is a perspective view by CG from a direction further different from FIG. It is an external view by CG of the same ceiling speaker. It is an external view by CG from a direction different from FIG. It is a figure which shows the state from which the cover in FIG. 4 was removed. It is a figure which shows the state in which the cover in FIG. 5 was removed. It is a perspective view from the same direction as FIG. It is a perspective view from the same direction as FIG. It is a perspective view from the same direction as FIG. It is an external view from the same direction as FIG. It is an external view from the same direction as FIG. It is a figure which shows the state from which the cover in FIG. 11 was removed. It is a figure which shows the state from which the cover in FIG. 12 was removed. It is an illustration figure which shows one state at the time of installation work of the same ceiling speaker. It is an illustration figure which shows the installation state of the same ceiling speaker. It is an illustration figure which shows the installation strata of the same ceiling speaker in the environment different from FIG. It is a figure which shows the frequency characteristic of the same ceiling speaker. It is a figure which shows the example of wiring of the conventional ceiling speaker as comparison object of the ceiling speaker. It is a figure showing the example of wiring of the ceiling speaker concerning the embodiment. It is a figure which shows the example of wiring different from FIG. 19 of the conventional ceiling speaker. It is a figure which shows the example of wiring different from FIG. 20 of the ceiling speaker which concerns on the embodiment. It is a perspective view by CG of the conventional ceiling speaker. It is an external view by the photograph of the conventional ceiling speaker. It is an illustration figure for demonstrating the installation point of the conventional ceiling speaker.

  One embodiment of the present invention will be described with reference to FIGS.

First, the perspective view by CG from the suitable direction of the ceiling speaker 10 which concerns on this embodiment in FIGS. 1-3 is shown. And FIG. 4 and FIG. 5 show an external view (six views) by CG of the ceiling speaker 10. Further, FIGS. 6 and 7 show a state in which a cover 12 described later in FIGS. 4 and 5 is removed. And the perspective view from the same direction as FIGS. 1-3 is shown to FIGS. 8-10. 11 and 12 show external views from the same direction as in FIGS. 4 and 5, respectively. And FIG. 13 and FIG. 14 show the state in which the cover 12 in FIG. 11 and FIG. 12 is removed. In addition, in FIG. 8 to FIG. 14, in consideration of these legibility, the R portion which is not originally represented by the diagram is also represented by the diagram as appropriate.

  As can be understood with reference to FIGS. 1 to 14, the ceiling speaker 10 according to the present embodiment has a dynamic speaker unit 14. The speaker unit 14 is housed in a hard resin case 18 as a housing together with other parts such as the matching transformer 16. The case 18 includes a substantially rectangular flat base 20 on which the components including the speaker unit 14 are mounted, and the above-described cover 12 covering the components mounted on the base 20.

  The base 20 is provided with a circular opening hole 20a for exposing the sound emitting surface 14a of the speaker unit 14 to the outside of the base 20 (case 18). The opening 20a is provided such that its center is located at the center in the lateral direction of the base 20 and the center is located slightly closer to one end than the center in the longitudinal direction of the base 20. . The opening 20a is provided with a protective strip 20b having a suitable shape, for example, a substantially mesh shape, for protecting the sound emitting surface 14a of the speaker unit 14. Of the protective strip 20b, a straight portion 20c passing through the center of the opening 20a and extending along the longitudinal direction of the base 20 has an appropriate dimension in the thickness direction of the base 20. Also, it functions as a rib to improve the mechanical strength of the base 20. Further, among the protective strips 20b, the two portions 20d and 20d which are adjacent to the rib 20c with the rib 20c interposed therebetween in the width direction of the base 20 and which are convexly curved toward the rib 20c are similarly base It has appropriate dimensions in the thickness direction of 20, that is, it functions as a rib. Furthermore, a part of the periphery of the opening 20a, specifically, the parts 20e and 20e excluding the parts in contact with the side edges of the base 20 and the vicinity thereof also have appropriate dimensions in the thickness direction of the base 20. That is, it is formed in the shape of a rib.

  Here, for example, it is assumed that the longitudinal direction of the base 20 is the longitudinal direction of the ceiling speaker 10 including the base 20. Then, it is assumed that the short direction of the base 20 is the width direction of the ceiling speaker 10 including the base 20. Furthermore, it is assumed that the direction orthogonal to each of the length direction and the width direction is the height direction of the ceiling speaker 10. In this case, the base 20 is slightly closer to one end than the center in the length direction, and at the center in the width direction of the base 20, that is, substantially in the center in the length direction and the width direction of the base 20, The speaker unit 14 will be located. The speaker unit 14 has the largest height dimension among the components mounted on the base 20, and the dimensions in the length direction and the width direction of the base 20 are also the largest.

  As components having a large size other than the speaker unit 14, there are a matching transformer 16 and an autotransformer 22 for an attenuator, in particular as a component having a large height. Among them, the matching transformer 16 is disposed between the speaker unit 14 and one end of the base 20 on the side where the speaker unit 14 is slightly deviated in the length direction of the base 20, and It is arranged as close as possible to the speaker unit 14. In the width direction of the base 20, the matching transformer 16 is disposed at the center in the width direction, that is, a virtual axis including the central axis of the sound emitting surface 14a of the speaker unit 14 and along the length direction of the base 20. Are placed on the plane of Furthermore, the direction of the matching transformer 16 itself is also determined. That is, the matching transformer 16 has a substantially rectangular parallelepiped hollow iron core 16 a and a winding 16 b wound around the iron core 16 a, and the iron core 16 a is used for the matching transformer 16 adopted here. The height dimension of the portion is larger than the height dimension of the winding 16b portion. Then, in order to miniaturize the entire ceiling speaker 10 including the cover 12 described in detail later, this matching transformer 16 is such that the size of the iron core 16a portion is shortened in the longitudinal direction of the ceiling speaker 10 (base 20). In this case, the opening of the hollow portion of the iron core 16a (the space in which the winding 16b is wound) is orthogonal to the longitudinal direction of the ceiling speaker 10.

  On the other hand, the auto transformer 22 is disposed on the opposite side of the matching transformer 16 with the speaker unit 14 interposed therebetween. The autotransformer 22 is also disposed on the above-mentioned imaginary plane including the central axis of the sound emitting surface 14 a of the speaker unit 14 and along the length direction of the base 20. The auto transformer 22 is disposed as close as possible to the speaker unit 14. Furthermore, as with the matching transformer 16, the auto transformer 22 has its own orientation. That is, this autotransformer 22 has a substantially rectangular parallelepiped hollow iron core 22a, and a winding 22b wound around the iron core 22a. With regard to the autotransformer 22 adopted here, the iron core is used. The height dimension of the 22a portion is larger than the height dimension of the winding 22b portion. The autotransformer 22 is oriented such that the size of the iron core 22a is shortened in the longitudinal direction of the ceiling speaker 10. That is, the opening of the hollow portion of the iron core 22a (the space in which the winding 22b is wound) here. Are arranged in a direction perpendicular to the longitudinal direction of the ceiling speaker 10.

  Furthermore, two terminal blocks 24 and 26 to which appropriate wiring is connected are provided at the edge portion of the base 20 on the side where the autotransformer 22 is disposed. The terminal blocks 24 and 26 are mounted on the printed wiring board 28 common to the autotransformer 22. The above-mentioned matching transformer 16 is mounted on another printed wiring board 30. In other words, the matching transformer 16 and the autotransformer 22 are mounted on the printed wiring boards 28 and 30 separately from each other so that the matching transformer 16 and the autotransformer 22 are arranged in one row across the speaker unit 14. ing.

  The other parts are smaller than the speaker unit 14, the matching transformer 16, and the auto transformer 22 and are disposed at appropriate positions, and more specifically, they are suitably mounted on two printed wiring boards 28 and 30. There is. However, in the longitudinal direction of the base 20, each component is disposed as close as possible to the speaker unit 14. As a result, the overall size of the ceiling speaker 10 including the base 20 in the longitudinal direction of the base 20, that is, the reduction of the length dimension, is achieved. In addition, in the width direction of the base 20, each component is disposed so as to be located inside the base 20 relative to both end edges of the speaker unit 14. As a result, the overall size of the ceiling speaker 10 including the base 20 in the width direction of the base 20, that is, the reduction of the width dimension, is achieved.

  And the cover 12 is attached to the said base 20 so that each component containing the speaker unit 14 mounted in this base 20 may be covered, and it is screwed in detail. The cover 12 has a substantially quadrangular pyramidal frustum shape having a portion covering the speaker unit 14 with the largest height dimension among the components mounted on the base 20 as an upper base. Miniaturization (in other words, slimming) of itself is achieved, and hence miniaturization of the ceiling speaker 10 is achieved. However, the portion 12 a of the case 12 that covers the matching transformer 16 is formed in a substantially rectangular parallelepiped shape so as to fit the outer shape of the matching transformer 16. The corners of the rectangular portion 12a are chamfered, and the matching transformer 16 is particularly located at the end of the ceiling speaker 10 (the side away from the speaker unit 14). In accordance with the shape (step) of the iron core 16a and the winding wire 16b described above, the chamfering is made larger. Similarly to this, the portion 12 b of the case 12 covering the autotransformer 22 is also formed in a substantially rectangular parallelepiped shape so as to conform to the outer shape of the autotransformer 22. In addition, the corners of the rectangular portion 12b are also formed in a beveled shape, and the autotransformer 22 is particularly located at the end of the ceiling speaker 10 (the side away from the speaker unit 14). In accordance with the shape of the iron core 22a and the winding wire 22b described above, it is made a large chamfered shape. In addition, in a portion corresponding to the upper surface of the rectangular parallelepiped portion 12b, a triangular arrow 12c indicating the direction when the ceiling speaker 10 is installed in a manner described later is integrally formed with the rectangular parallelepiped portion 12b (cover 12) There is.

  Further, on the outer side surface of the cover 12, a generally concave elongated restraining groove 12d for restraining a spring coil as an expansion elastic body (not shown) used for mounting a panel (not shown) is provided. Specifically, the restraining groove 12 d passes through the central axis of the sound emitting surface 14 a of the speaker unit 14 and extends in a direction oblique to each of the length direction and the width direction of the ceiling speaker 10. , Is provided. At the same time, a pair of through holes 12 e and 12 f through which both ends of the spring coil are separately inserted are provided in the vicinity of a portion of the cover 12 that corresponds to both ends of the restraining groove 12 d. That is, the pair of through holes 12 e and 12 f is a position that includes the central axis of the sound emitting surface 14 a of the speaker unit 14 and deviates from the aforementioned virtual plane along the length direction of the cover 12 (base 20) It is provided at a position on the inner side of the cover 12 than both end edges of the speaker unit 14 in the width direction of the cover 12. A pair of similar through holes 20f and 20g are provided at positions of the base 20 corresponding to the through holes 12e and 12f. By providing these through holes 12e, 12f, 20f and 20g at such positions, for example, the through holes 12e, 12f, 20f and 20g can be compared with the case where they are provided on an imaginary plane as referred to herein. An increase in the length dimension of the case 18 due to the provision of the holes 12e, 12f, 20f and 20g is suppressed, and in turn, an increase in the length dimension of the entire ceiling speaker 10 is suppressed. Further, for example, the through holes 12e, 12f, 20f and 20g are provided as compared to the case where the through holes 12e, 12f, 20f and 20g are provided at positions outside the both ends of the speaker unit 14 in the width direction of the case 18. An increase in the width dimension of the case 18 due to the provision of the is suppressed, and in turn, an increase in the width dimension of the entire ceiling speaker 10 is suppressed.

  Here, focusing on the base 20 again, in order to screw the ceiling speaker 10 including the base 20 to the ceiling plate 100 described later, if necessary, in the vicinity of the pair of through holes 20 f and 20 g in the base 20 described above. A pair of screw insertion holes 20h and 20i are provided. The cover 12 is provided with appropriate recesses 12g and 12h for avoiding interference with the pair of screw insertion holes 20h and 20i.

  Furthermore, at one side edge of the base 20, two projecting portions 20j and 20k are provided, which protrude in the direction opposite to the side where the case 12 is attached, that is, downward. The protrusions 20 j and 20 k are provided such that the edge portions thereof are positioned outward of the peripheral edge of the sound emitting surface 14 a in the radial direction of the central axis of the sound emitting surface 14 a of the speaker unit 14. The other side edge of the base 20 is also provided with two similar protrusions 20 n and 20 p.

  In addition, the width dimension of the base 20 is narrowed at an intermediate portion in the length direction of the base 20, for example, a portion where the speaker unit 14 is located, so to say, curved necks 20q and 20q are provided. There is. Further, in the portions where the constrictions 20q and 20q are provided, the above-mentioned protrusions 20j, 20k, 20n and 20p are not provided, that is, the thickness of both side edges of the base 20 is suppressed. There is.

  Then, at an appropriate position of the base 20, for example, at an appropriate position near one side edge of the base 20, a wire winding hole 20r is provided in which a wire for preventing the falling of the ceiling speaker 10 is wound. There is. In accordance with this, the cover 12 is provided with an appropriate notch 12i to enable winding of the wire to the wire winding hole 20r.

  Further, each of the above-mentioned parts includes a plurality of, for example, four switches, and the base 20 has the operation knobs 32a and 32b for operating the four switches, in other words, the four switches. , 32c and 32d are exposed to the outside of the cover 18, four through holes 20s, 20t, 20u and 20v are provided.

  Focusing on the cover 12 again, the cover 12 is provided with heat dissipation holes 12j, 12j,... Of an appropriate shape and size.

  The ceiling speaker 10 configured as described above is installed in the following manner. That is, appropriate wiring is connected to the two terminal blocks 24 and 26. Then, as shown by an arrow 102 in FIG. 15A, from the front surface side of the ceiling plate 100 to the back surface side of the ceiling plate 100 via a circular attachment hole 100a provided in the ceiling plate 100. That is, the ceiling speaker 10 is inserted into the ceiling. At this time, the ceiling speaker 1 is inserted into the mounting hole 100 a from the end where the two terminal blocks 24 and 26 are provided, that is, in the direction indicated by the triangular arrow 12 c described above.

  Here, when the state shown in FIG. 15 (a) is viewed from the front of the ceiling speaker 10, it becomes as shown in FIG. 15 (b). As can be seen from FIG. 15B, the ceiling speaker 10 is inserted obliquely to the circular mounting hole 100a, whereby the mounting hole 100a becomes flat and oval for the ceiling speaker 10. This becomes an obstacle in the installation work of the ceiling speaker 100a, but as described above, since the ceilings 20q and 20q are provided in the ceiling speaker 10 (base 20), the ceiling speaker 10 and the mounting hole 100a Thus, a margin is created, and the installation work of the ceiling speaker 10 can be facilitated. Moreover, since the ceiling speaker 10 (cover 12) is formed in a substantially square frustum as described above, the installation work of the ceiling speaker 10 can be facilitated also by this.

  Then, after the ceiling speaker 10 is inserted (passed) through the mounting hole 100a, the ceiling speaker 10 is placed on the ceiling, as shown in FIG. That is, the said ceiling speaker 10 is installed so that the sound emission surface 14a of the speaker unit 14 may be exposed to the surface side of the ceiling board 100 via the attachment hole 100a. At this time, the ceiling speaker 10 is installed in a state where the tips (lower ends) of the four protrusions 20 j, 20 k, 20 n and 20 p described above are in contact with the back surface (upper surface) of the ceiling plate 100. Thereafter, as in the prior art, hooks 34 and 34 provided at both ends of a spring coil (not shown) are engaged with corresponding hooks of the panel (not shown), and the panel is attached to the ceiling speaker 10.

  The ceiling speaker 10 of the present embodiment employs a speaker unit 14 having a diameter of 80 mm (of the sound emitting surface 14a). From this, the length dimension L of the ceiling speaker 10 is set to L = 180 mm. The width dimension W of the ceiling speaker 10 is W = 80 mm, that is, the aperture diameter of the speaker unit 14. The height dimension H of the ceiling speaker 10 is H = 54 mm. That is, the ceiling speaker 10 according to the present embodiment is much smaller than the conventional ceiling speaker 1 described above, and a size reduction of about 50% is realized. The reason why the 80 mm aperture speaker unit 14 is adopted is to satisfy the standard of L class with 1 W input while considering the cost (profitable) aspect, and it is about that Because the diameter of the

  In order for the small-sized ceiling speaker 10 of the present embodiment to be installed on the ceiling in the above manner, the opening diameter Φ of the mounting hole 100 a provided in the ceiling plate 100 is sufficient if Φ = 100 mm. The aperture diameter Φ of Φ = 100 mm is sufficient not only because the ceiling speaker 10 is miniaturized but also that the ceiling 20 is provided with the constrictions 20 q and 20 q as described above, and the ceiling speaker 10 The fact that the outer shape of (cover 12) is roughly a square frustum also contributes significantly. It is also natural that the opening diameter 開口 of the mounting hole 100a is smaller than the length L of the ceiling speaker 10 (天井 <L) and larger than the width W of the ceiling speaker 10 (Φ> W), The height dimension H of the ceiling speaker 10 is larger (Φ> H).

  The opening diameter Φ of the mounting hole 100a of == 100 mm is the same as the opening diameter of the mounting hole required for the installation of recent downlights and emergency lighting fixtures. Therefore, it is possible to improve the working efficiency when providing the mounting holes for the downlight and the emergency lighting apparatus, including the mounting holes 100 a for the ceiling speaker 10. In addition, since the opening diameter Φ of the mounting hole 100a is small as described above, the outer diameter of the panel covering the mounting hole is also small, and the designability when the ceiling speaker 10 including the panel is installed is improved compared to the prior art. .

  Furthermore, as the depth dimension A of the ceiling, it is sufficient if A = 70 mm or more. On the other hand, since the conventional ceiling speaker 1 requires the depth dimension A 'of A' = 130 mm or more as described above, the ceiling speaker 10 according to the present embodiment is different from the conventional ceiling speaker 1 in this embodiment. For example, it can be expected that the market can be expanded by expanding the scenes that can be installed.

  In addition, the ceiling speaker 10 of the present embodiment can be installed, for example, as a substitute for the conventional ceiling speaker 1. In this case, since the ceiling speaker 10 of the present embodiment is attached to the mounting hole 100 a having an opening diameter Φ of 150 mm, the ceiling speaker 10 may be a mounting hole depending on the installation situation (position) of the ceiling speaker 10. There is a concern about falling through 100a. However, the ceiling speaker 10 according to the present embodiment includes the four protrusions 20j, 20k, 20n and 20p described above, and as shown in FIG. 17, these four protrusions 20j, 20k, 20n and 20p are attached By engaging the hole 100a, the ceiling speaker 10 is prevented from falling through the mounting hole 100a. The distance C between the edges of the protrusions 20j and 20k (or 20k and 20n) in the longitudinal direction of the ceiling speaker 10 is, for example, 134 mm.

  Further, according to the ceiling speaker 10 of the present embodiment, so-called arc-shaped ribs 20 e and 20 e are provided to surround the periphery of the opening hole 20 a for exposing the sound emitting surface 14 a of the speaker unit 14. Sound quality can be improved. That is, the sound is emitted from the front side of the radiation surface 14 a of the speaker unit 14, and at the same time, the sound of the opposite phase is emitted from the back side of the radiation surface 14 a. Then, the sound in the opposite phase wraps around the sound emitting surface 14a through a portion other than the opening hole 20a, in particular, through the pair of through holes 20f and 20g provided in the base 20 for inserting the spring coil. It is feared that the sound emitted from the sound emission surface 14a is canceled out. However, the arc-shaped ribs 20e and 20e are provided, and in particular, the arc-shaped ribs 20e and 20e intervene between the pair of opening holes 20f and 20g and the opening hole 20a (that is, such positions). By being related), the wraparound of the sound of the opposite phase is suppressed, and thus the sound quality is improved.

  FIG. 18 shows the frequency characteristics when the arcuate ribs 20e and 20e are provided and when the arcuate ribs 20e and 20e are not provided. In FIG. 18, the thick solid curve α shows the frequency characteristics when the arcuate ribs 20e and 20e are provided, and the thick dashed curve β is provided with the arcuate ribs 20e and 20e. It shows the frequency characteristic when there is no. As can be seen from FIG. 18, in the frequency band lower than approximately 1 kHz, the arcuate ribs 20 e and 20 e are provided when the arcuate ribs 20 e and 20 e are provided. A sound pressure level higher than 1 dB can be obtained as compared to the case where no sound pressure is detected. This means that it contributes to an increase in the sound pressure level in the frequency band of the voice alarm sound second signal, and in particular, although the small speaker unit 14 of 80 mm is adopted, 1 W as described above It is extremely effective to satisfy the criteria of L class at the input of. On the other hand, in the frequency band higher than 1 kHz, there is no particular difference between the case where the arcuate ribs 20e and 20e are provided and the case where the arcuate ribs 20e and 20e are not provided. In other words, there is no disadvantage due to the provision of the arcuate ribs 20e and 20e. As described above, the provision of the arc-shaped ribs 20e and 20e improves the sound quality, so that not only for emergency broadcast but also application for business broadcast can be realized. The so-called boundary frequency, which is approximately 1 kHz here, is determined by the shape and size (capacity) of the case 18.

  The contents described in the present embodiment are one specific example of the present invention, and do not limit the scope of the present invention.

  For example, although the dynamic type whose diameter is 80 mm is adopted as the speaker unit 14, the dynamic type whose size is other than this may be adopted. In this case, of course, the overall size of the ceiling speaker 10 changes and the shape may change depending on the size of the speaker unit 14 including the aperture. And, as the speaker unit 14, one other than the dynamic type may be adopted.

  Furthermore, the auto transformer 22 for attenuator may not be mounted. That is, the attenuator including the auto transformer 22 may not be mounted, and an external attenuator may be used. In the ceiling speaker 10 according to the present embodiment, the common case 18 is used, and particularly the common cover 12 is used, regardless of whether the attenuator is mounted or not. However, separate covers 12 may be used in the case where the attenuator is mounted and in the case where the attenuator is not mounted. In particular, when the attenuator is not mounted, a cover not provided with the rectangular portion 12b which is a portion covering the autotransformer 22 may be used, that is, such a cover may be prepared. Further, as an attenuator, not an autotransformer system using an autotransformer 22 but a resistance system using an appropriate resistor may be adopted. Also in this case, the autotransformer 22 is not provided. The rectangular portion 12 b for covering the transformer 22 is not necessary, and a cover having a shape according to this may be used.

  By the way, in the conventional ceiling speaker 1 described above, in particular, the attenuator is not mounted, and in the type using the external attenuator, the wiring to each of the terminal blocks 6 and 7 is complicated, which causes a connection error. Another problem is that it is easy. According to the ceiling speaker 10 of the present embodiment, a device for solving this problem is also provided.

  Specifically, the terminal blocks 6 and 7 of the conventional ceiling speaker 1 are configured as shown in FIG. That is, one terminal block 6 is a relay terminal connected to the main line, and includes three N (NORMAL: normal) terminals 6a, 6a and 6a, and three R (URGENCY: emergency) terminals 6b, 6b and 6b , And three COM (COMMON: common) terminals 6c, 6c and 6c. The other terminal block 7 is a speaker input terminal connected to the speaker unit 2 and includes two SP-HOT (SPEAKER HOT: anode) terminals 7 a and 7 a and two SP-COM (SPEAKER COMMON: cathode) And terminals 7b and 7b. The SP-HOT terminals 7 a and 7 a of the speaker input terminal 7 are connected to the anode input terminal of the speaker unit 2. The SP-COM terminals 7 b and 7 b of the speaker input terminal 7 are connected to the cathode input terminal of the speaker unit 2. However, strictly speaking, the above-mentioned matching transformer is provided on the input side of the speaker unit 2, but for convenience of explanation, the illustration of the matching transformer is omitted here. Furthermore, the SP-COM terminals 7 b and 7 b of the speaker input terminal 7 are connected to the COM terminals 6 c, 6 c and 6 c of the relay terminal 6.

  When the conventional ceiling speaker 1 provided with such a relay terminal 6 and the speaker input terminal 7 is applied to a 3-wire speaker line, the N lines 50a, R of the wiring 50 (from an amplifier not shown) of the main line The line 50b and the COM line 50c are connected to the N terminal 6a, the R terminal 6b and the COM terminal 6c of the relay terminal 6, respectively. Similarly to this, the N line 52a, R line 52b and COM line 52c of the feed wiring 52 (to another speaker not shown) to the main line respectively correspond to the N terminal 6a, R terminal 6b and COM terminal 6c of the relay terminal 6. Connected to Then, an external attenuator (ATT) 70 is connected. The external attenuator 70 has one N terminal 70a, one R terminal 70b and one SP (SPEAKER: anode) terminal 70c. Among them, the N terminal 70 a is connected to the N terminal 6 a of the relay terminal 6 of the ceiling speaker 1 via the N line 54 a of the attenuator connection wiring 54 laid for the external attenuator 70. The R terminal 70 b of the external attenuator 70 is connected to the R terminal 6 b of the relay terminal 6 of the ceiling speaker 1 via the R line 54 b of the attenuator connection wiring 54. Furthermore, the SP terminal 70 c of the external attenuator 70 is connected to the SP-HOT terminal 7 a of the speaker input terminal 7 of the ceiling speaker 1 via the SP line 54 c of the attenuator connection wiring 54.

  As can be understood from the configuration in FIG. 19, only the connection to the relay terminal 6 is required for the trunk lines 50 and 52 including the feed wiring 52. However, the attenuator connection wiring 54 for connecting the external attenuator 70 needs to be connected to both the relay terminal 6 and the speaker input terminal 7, which is complicated. For this reason, it is easy to cause a connection error.

  On the other hand, each terminal block 24 and 26 of the ceiling speaker 10 of this embodiment is set as a structure as shown in FIG. That is, one terminal block 24 as the first terminal block is a so-called speaker input / relay terminal which bears a function as a relay terminal and a function as a part of a speaker input terminal, and three N terminals 24 a , 24a and 24a, an R terminal group including three R terminals 24b, 24b and 24b, and a COM terminal group including three COM terminals 24c, 24c and 24c. The other terminal block 26 as the second terminal block is an attenuator connection terminal specialized only for connection with the external attenuator 70, and an N terminal 26a corresponding to each of the terminals 70a, 70b and 70c of the external attenuator 70. , R terminal 26b and SP terminal 26c. The N terminal 26a of the attenuator connection terminal 26 is connected to the N terminals 24a, 24a and 24a of the speaker input / relay terminal 24 on the printed wiring board 28 described above. The R terminal 26 b of the attenuator connection terminal 26 is connected to the R terminals 24 b, 24 b and 24 b of the speaker input / relay terminal 24 on the printed wiring board 28. In addition to this, another SP terminal 26c is provided. The SP terminals 26 c and 26 c of the attenuator connection terminal 26, that is, the SP terminal group are connected to the anode input terminal of the speaker unit 14. The cathode input terminal of the speaker unit 14 is connected to each of the COM terminals 24 c, 24 c and 24 cb of the speaker input / relay terminal 24. Strictly speaking, the matching transformer 16 is provided on the input side of the speaker unit 14, but the illustration of the matching transformer 16 is omitted here. Further, between the N terminals 24a, 24a and 24a of the speaker input / relay terminal 24 and the SP terminals 26c and 26c of the attenuator connection terminal 26, the state in which the both are connected (ON) and the state not connected (OFF) For example, a slide-type manual switch 36 is provided as switching means for selectively switching between the above-described states. The operation of the manual switch 36 is performed by one of the four operation knobs 32a, 32b, 32c and 32d described above. In other words, the operation switch 32 a is attached to the manual switch 36.

  When the ceiling speaker 10 of the present embodiment provided with such a speaker input / relay terminal 24 and the attenuator connection terminal 26 is applied to a three-wire speaker line, the N line 50a and the R line 50b of the main line 50 And the COM line 50c are connected to the N terminal 24a, the R terminal 24b, and the COM terminal 24c of the speaker input / relay terminal 24, respectively. Similarly, the N line 52a, the R line 52b and the COM line 52c of the feed wiring 52 to the main line are also connected to the N terminal 24a, R terminal 24b and COM terminal 24c of the speaker input / relay terminal 24, respectively. Then, for the external attenuator 70, the attenuator connection terminal of the ceiling speaker 10 through the N line 54a, the R line 54b and the SP line 54c of the attenuator connection wiring 54 respectively at the N terminal 70a, the R terminal 70b and the SP terminal 70c. It is connected to the 26 N terminal 26a, R terminal 26b and SP terminal 26c. Furthermore, it is also possible to provide a branch line 56 as a third line which can be handled in the same manner as the feed line 52 (in other words, capable of achieving the same function as the feed line 52). That is, the N line 56a, the R line 56b and the COM line 56c of the branch wiring 56 are connected to the N terminal 24a, R terminal 24b and COM terminal 24c of the speaker input / relay terminal 24, respectively.

  As described above, according to the ceiling speaker 10 of the present embodiment, only the connection to the speaker input / relay terminal 24 is sufficient for the trunk lines 50 and 52 including the feed wiring 52. The attenuator connection wiring 54 only needs to be connected to the attenuator connection terminal 26 specialized for this. Moreover, the connection to the attenuator connection terminal 26 is completely the same as the connection to the external attenuator 70. Therefore, the wiring is extremely simple as compared with the conventional ceiling speaker 1, and hence connection errors can be prevented. Furthermore, since the branch wiring 56 can be provided, it is possible to flexibly cope with the environment (the size, the layout, and the like of the indoor space) in which the ceiling speaker 10 is installed. In the configuration shown in FIG. 20, the manual switch 36 is in the OFF state.

  Further, the configuration in which the crossover wiring 58 is provided will be considered. First, in the conventional case, as shown in FIG. 21, the SP-HOT line 58a of the crossover wiring 58 is connected to the SP-HOT terminal 7a of the speaker input terminal 7 in the ceiling speaker 1 (SP1 ') of the delivery source. At the same time, the SP-COM line 58 c of the crossover wiring 58 is connected to the SP-COM terminal 7 b of the speaker input terminal 7. Generally, a 3-wire (3-core) cable having the same specification as that of the trunk line 50 or the like is laid as the crossover wiring 58, so one line (R line) 58b is left. Therefore, the excess line 58b needs to be end-treated to insulate its end. Then, in the ceiling speaker 1 (SP 2 ′) of the passing destination, the SP-HOT line 58 a of the crossover wiring 58 is connected to the SP-HOT terminal 7 a of the speaker input terminal 7 and the SP of the speaker input terminal 7. The SP-COM line 58c of the crossover wiring 58 is connected to the -COM terminal 7b. Also at this destination, since one line 58b of the crossover wiring 58 remains, it is necessary to perform the terminal processing of the remaining line 58b.

  According to the configuration shown in FIG. 21, the speaker unit 2 of the ceiling speaker 1 (SP1 ') of the delivery source and the speaker unit 2 of the ceiling speaker 1 (SP2') of the delivery destination are mutually connected in parallel. Therefore, the external attenuator 70 functions in common to both the speaker unit 2 of the ceiling speaker 1 (SP1 ') of the delivery source and the speaker unit 2 of the ceiling speaker 1 (SP2') of the delivery destination. .

  However, in the conventional configuration shown in FIG. 21, no wire is connected to the relay terminal 6 of the ceiling speaker 1 (SP 2 ′) of the delivery destination. At first glance, it seems that the wiring to the ceiling speaker 1 (SP2 ') of the delivery destination is inappropriate (in other words, misunderstood), especially at the site, and from this, the ceiling speaker 1 of the delivery destination (( An incorrect wiring may be made to the relay terminal 6 of SP2 ′), that is, a connection error may occur. In addition, it is necessary to perform the end processing of the excess line 58c as described above in each of the delivery source and delivery destination, which is extremely troublesome.

  On the other hand, in the case of the ceiling speaker 10 of the present embodiment, as shown in FIG. 22, in the ceiling speaker 10 (SP1) of the delivery source, the SP of the crossover 58 is connected to the SP terminal 26c of the attenuator connection terminal 26. The HOT line 58a is connected. The R line 58b of the crossover wiring 58 is connected to the R terminal 24b of the speaker input / relay terminal 24 in the ceiling speaker 10 (SP1) of the transfer source, and the COM terminal of the speaker input / relay terminal 24 The SP-COM line 58c of the crossover wiring 58 is connected to 24c. On the other hand, in the ceiling speaker 10 (SP2) of the passing destination, the SP-HOT line 58a and R line 58b of the crossover wiring 58 are respectively connected to the N terminal 24a, R terminal 24b and COM terminal 24c of the speaker input / relay terminal 24. The COM line 58c is connected. The manual switch 36 of the ceiling speaker 10 (SP1) of the delivery source is in the OFF state. Then, the manual switch 36 of the ceiling speaker 10 (SP2) of the delivery destination is turned on.

  According to the configuration shown in FIG. 22, similarly to the configuration shown in FIG. 21, the speaker unit 14 of the ceiling speaker 10 (SP1) of the passing source and the speaker unit 14 of the ceiling speaker 10 (SP2) of the passing destination are Connected in parallel to each other. Therefore, the external attenuator 70 functions in common to both of the speaker unit 14 of the ceiling speaker 10 (SP1) of the delivery source and the speaker unit 14 of the ceiling speaker 10 (SP2) of the delivery destination.

  Further, in the configuration shown in FIG. 22, if attention is paid to the ceiling speaker 10 (SP2) of the delivery destination, the SP-HOT line 58a of the crossover wiring 58 connected to the N terminal 24a of the speaker input / relay terminal 24 is N lines. Assuming that the connection of the crossover wiring 58 to the speaker input / relay terminal 24 is similar to the connection of the trunk line 50 or the like to the speaker input / relay terminal 24 of the ceiling speaker 10 (SP1) of the passing source. Apparently, the speaker 10 (SP2) of the destination may be wired in the same manner as the speaker 10 (SP1) of the source. Thus, connection errors can be prevented. Although the R line 58b of the crossover wiring 58 does not have a special function (meaningless) electrically, it has a great meaning in that it contributes to the prevention of connection errors.

  As described above, according to the ceiling speaker 10 of the present embodiment, it is possible to prevent a connection error at the time of wiring in addition to the realization of the miniaturization. The three types of terminals 24a, 24b and 24c that constitute the speaker input / relay terminal 24 are not limited to three each (especially if it is spatially permitted including the size of the case 18), and other than that A number may be provided.

10 ceiling speaker 12 cover 14 speaker unit 16 matching transformer 18 case 20 base 22 auto transformer

Claims (9)

The speaker unit is installed on the back side of the ceiling plate so that the sound emitting surface of the speaker unit is exposed to the front side of the ceiling plate by being inserted on the back side of the ceiling plate through the mounting holes provided in the ceiling plate. Ceiling speakers,
A housing that accommodates a plurality of component elements including the speaker unit;
The housing is a base on which the component element is mounted, and the base is mounted on the back surface side of the ceiling plate so as to straddle the mounting hole, and a cover which covers the component element mounted on the base Including and
The dimensions of the housing in a first direction orthogonal to the central axis of the sound emission surface of the speaker unit are the dimensions of the housing in a second direction orthogonal to the central axis of the sound emission surface and the first direction Greater than
The plurality of component elements together with the speaker unit have a first electric component and a second electric component whose dimensions in the second direction and in the direction along the central axis of the sound emitting surface are smaller than those of the speaker unit And, and
The speaker unit is disposed on the base substantially at the center in each of the first direction and the second direction,
The first electric component is disposed in a first virtual plane defined between one end of the base in the first direction and the speaker unit, and the other end of the base in the first direction and the speaker An overhead speaker in which the cover can be formed in a substantially frustum shape by arranging the second electrical component in a second virtual plane defined between the unit and the unit . The first electrical component is a matching transformer, and the second electrical component is an attenuator transformer.
A ceiling speaker according to claim 1 . The cover is formed in a generally square frustum with the portion covering the speaker unit as the upper base and the base as the lower base.
A ceiling speaker according to claim 1 . In the inclined surface connecting the upper bottom and the lower bottom, the portions covering the first electric component and the second electric component conform to the respective shapes of the first electric component and the second electric component. The cover is formed in a substantially rectangular shape
The ceiling speaker according to claim 3 . A pair of through-holes through which a substantially linear elastic member for drawing a panel attached to cover the sound emitting surface of the speaker unit together with the mounting holes on the surface side of the ceiling plate is inserted. Provided in the case,
One of the pair of through holes is provided at one end side of the housing in the second direction at a position between the first virtual plane and the speaker unit .
The other of the pair of through holes is a position between the second virtual plane and the speaker unit, and is provided on the other end side of the housing in the second direction.
A ceiling speaker according to claim 1. In order to expose the sound emitting surface to the outside of the housing, it is provided along a part or all of the periphery of the opening formed in the housing, and along the direction along the central axis of the sound emitting surface The apparatus further comprises a projecting wall projecting toward the outside of the housing.
A ceiling speaker according to claim 1. The portion of the casing facing the back surface of the ceiling plate is provided at a position outward of the peripheral edge of the sound emitting surface in the radial direction of the central axis of the sound emitting surface, along the central axis of the sound emitting surface Further comprising a protrusion projecting toward the outside of the housing along the
A ceiling speaker according to claim 1. Of the portion of the casing facing the back surface of the ceiling plate, the middle in the first direction is narrowed inside the casing in the second direction,
A ceiling speaker according to claim 1. Further comprising a first terminal block and a second terminal block,
The first terminal block has a first normal terminal group including a plurality of first normal terminals, a first emergency terminal group including a plurality of first emergency terminals, and a common terminal group including a plurality of common terminals. And
The second terminal block includes at least one second normal terminal mutually connected with the first normal terminal group, and at least one second emergency terminal mutually connected with the first emergency terminal group , And a speaker input terminal group including a plurality of speaker input terminals;
It further comprises switching means for selectively switching between a state in which the first normal terminal group and the speaker input terminal group are connected to each other and a state in which they are not connected.
One of the pair of input terminals of the speaker unit is connected to the speaker input terminal group,
The other of the pair of input terminals of the speaker unit is connected to the common terminal group,
A ceiling speaker according to claim 1.