JP2017220873A - Ceiling speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceiling speaker which is smaller than the conventional one.SOLUTION: A separate type ceiling speaker according to the present invention, includes a dynamic type speaker unit 14 of which an aperture is equal to 80 mm. The speaker unit 14 is approximately arranged at a center of a base 20 forming a case 18 as a casing. Other components are arranged to be closed to the speaker unit 14 in a longitudinal direction of the base 20. In a width direction of the base 20, the components are arranged on the side of the base 20 inner from both edges of the speaker unit 14. A cover 12 forming the case 18 together with the base 20 is formed in a shape of an almost trapezoid of a quadrangular pyramid with an upper bottom of a part covering the speaker unit 14. Thus, a small ceiling speaker 10 which can be set under the condition that an opening aperture of an attachment hole is equal to 100 mm and a depth dimension of a ceiling back is equal to 70 mm can be materialized.SELECTED DRAWING: Figure 8

Description

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

  Conventionally, for example, this type of ceiling speaker is disclosed in Non-Patent Document 1. Referring to FIGS. 23 and 24, the conventional ceiling speaker 1 includes a dynamic speaker unit 2. The speaker unit 2 is housed in a hard resin case 3 as a housing together with other components such as a matching transformer (not shown). The case 3 includes a substantially rectangular flat base 3a on which components including the speaker unit 2 are mounted, and a cover 3b that covers the components mounted on the base 3a. The base 3a is provided with a circular opening 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 hole 3c is provided such that its center is located at the center in the short direction of the base 3a, and the center is located slightly closer to one edge than the center in the longitudinal direction of the base 3a. . Furthermore, a substantially spider web-shaped protective strip 3d for protecting the sound emitting surface 2a of the speaker unit 2 is provided in the opening hole 3c. In addition, a portion 3e of the protective strip 3d that passes through the center of the opening 3c and extends 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 substantially dome shape so as to cover the speaker unit 2. Further, on the outer surface of the dome-shaped portion 3f, there is a substantially concave elongate restraining groove 3g for restraining a spring coil 5 as a stretchable elastic body used for mounting the panel 4 described later. It passes through the apex and is provided along the longitudinal direction of the case 3 (base 3a). In addition, 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 both ends of the restraining groove 3g. In addition, a pair of similar through holes 3j and 3k are also provided at portions corresponding to the through holes 3h and 3i of the base 3a. Further, a 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 so as to cover the above-described matching transformer. In addition to the matching transformer, an autotransformer for an attenuator (volume controller) may be provided. In this case, the autotransformer is also housed in the rectangular parallelepiped portion 3n. In addition, the rectangular parallelepiped portion 3n is provided with two terminal blocks 6 and 7 to which appropriate wiring (cable) is connected exposed to the outside.

  The ceiling speaker 1 configured as described above is installed in the following manner. First, appropriate wiring is connected to the two terminal blocks 6 and 7. Then, as shown with an arrow 3p in FIG. 25A, from the front surface side of the ceiling plate 8 to the back surface side of the ceiling plate 8 through a circular mounting hole 8a provided in the ceiling plate 8. That is, the ceiling speaker 1 is inserted into the back of the ceiling. At this time, the ceiling speaker 1 is usually inserted into the mounting hole 8a from the end portion side (cuboid 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 connected to 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 board 8 through the mounting hole 8a. Placed in. In this state, as shown by an arrow 5a in FIG. 25 (c), hooks 5b and 5b provided at both ends of the spring coil 5 are connected to the corresponding hook locking portions 4a and 4a of the substantially disk-shaped panel 4, respectively. It is locked to 4a. As a result, the panel 4 is attracted 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. The panel 4 covers the sound emitting surface 2a of the speaker unit 2 together with the mounting holes 8a. Thereby, 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 sandwiched in cooperation with the panel 4 by the elastic force of the spring coil 5, but the ceiling plate 8 is fixed to the ceiling plate 8 with an appropriate fixing member such as a screw as necessary. Sometimes fixed.

TOA Corporation, Internet homepage, product information, ceiling speakers “CM-1830A” and “CM-1830AT”, [Search June 7, 2016], 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

  By the way, this conventional ceiling speaker 1 employs a speaker unit 2 having a diameter (of the sound emitting surface 2a) of about 120 mm. Therefore, for example, if the longitudinal direction of the case 3 (base 3a) of the ceiling speaker 1 is the length direction of the ceiling speaker 1, the dimension L ′ in the length direction of the ceiling speaker 1 is L ′ = 215 mm. If the width direction 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. Further, assuming that the direction orthogonal to the length 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 ′ = 80 mm. In order for the ceiling speaker 1 having such a size to be installed behind the ceiling in the above-described manner, the opening diameter Φ ′ of the mounting hole 8a provided in the ceiling plate 8 needs to be at least Φ ′ = 150 mm. The upper limit of the opening hole Φ ′ is suitably about 160 mm. Furthermore, the height dimension of the ceiling, that is, the depth dimension A ′, needs to be A ′ = 130 mm or more. Further, the panel 4 having an outer diameter B ′ of B ′ = 180 mm is employed.

  That is, when the state in which the conventional ceiling speaker 1 including the panel 4 is installed is viewed from the front surface side of the ceiling plate 8, the speaker having the panel 4 having an outer diameter B ′ of B ′ = 180 mm is embedded in the ceiling plate 8. Looks like. Thereby, the design of the indoor space including the ceiling plate 8 to which the panel 4 is attached is maintained. On the other hand, for example, a downlight or a ceiling-embedded emergency lighting apparatus may be installed in the same space (ceiling board 8). Recent downlights and ceiling-embedded emergency lighting fixtures have an opening diameter of the mounting hole of 100 mm, and many 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 fixture, the size of the panel 4 corresponding to the appearance of the conventional ceiling speaker 1 is more conspicuous than the downlight or emergency lighting fixture. Consequently, there is a problem that the design of the space is impaired. For this reason, the market demands miniaturization of ceiling speakers including panels. Also, for example, if the opening diameters of the mounting holes necessary for the installation of the ceiling speaker are the same as the opening diameters of the mounting holes necessary for the installation of the downlight or emergency lighting equipment, that is, 100 mm, these mounting holes are provided. The work efficiency at the time of installation is improved. For this reason, miniaturization of the ceiling speaker including the panel is required. In addition, if the size of the ceiling speaker is reduced, it can be installed in situations where the depth of the ceiling is even smaller, and the market is expected to expand.

  Therefore, an object of the present invention is to provide a ceiling speaker that is smaller than the conventional one.

  In order to achieve this object, the present invention is installed on the back surface side of the ceiling plate so that the sound emitting surface of the speaker unit is exposed to the front surface side of the ceiling plate through a mounting hole provided in the ceiling plate. Assuming a ceiling speaker. Under this premise, a housing for accommodating a plurality of component elements including a speaker unit is provided. Here, the dimensions of the casing in the first direction orthogonal to the central axis of the sound emitting surface of the speaker unit are the dimensions of the casing in the second direction orthogonal to the central axis of the sound emitting surface and the first direction, respectively. Bigger than. And the 1st specific element with the largest dimension in the direction in alignment with the central axis of the sound-emitting surface of a speaker unit among several component elements is arrange | positioned in the approximate center in each of the 1st direction inside a housing | casing, and a 2nd direction. Has been. In addition, a second specific element different from the first specific element among the plurality of component elements is arranged on a virtual plane including the central axis of the radiation surface of the speaker unit and along the first direction.

  That is, according to the present invention, a plurality of component elements including the speaker unit are accommodated in the housing. Here, for example, the first direction is the length direction of the housing, and the second direction is the width direction of the housing. 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. In addition, among the component elements including the speaker unit, the first specific element having the largest dimension in the height direction of the casing, that is, the height dimension, is approximately the center in each of the length direction and the width direction in the casing. Located in. And the 2nd specific element different from a 1st specific element is located among the said component elements on the virtual plane which contains the central axis of the radiation | emission surface of a speaker unit and follows a length direction. Thereby, for example, the outer shape of the housing can be formed in a substantially frustum shape (in other words, a mountain shape), in other words, each component can be housed in the substantially frustum-shaped housing. Thus, 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 on the back of the ceiling through the mounting hole of the ceiling speaker can be facilitated. Then, the opening diameter of the mounting hole can be reduced, and the depth dimension of the back of the ceiling where the ceiling speaker can be installed can be reduced.

  The virtual plane referred to here is a first virtual plane between one end in the length direction of the housing and the first specific element described above, the other end in the length direction of the housing, and the first specific element. And a second virtual plane between them. And the above-mentioned 2nd specific element may be arrange | positioned to at least one on these 1st virtual planes and a 2nd virtual plane.

  Moreover, the 1st specific element said here may be a thing with the largest dimension in the width direction of a housing | casing among each component elements. And the 2nd specific element shall exist in the inside of this housing | casing rather than the both-ends edge of a 1st specific element in the width direction of a housing | casing, ie, shall be settled.

  In the present invention, the sound emitting surface of the speaker unit may be covered with the panel from the surface side of the ceiling board together with the mounting holes. This panel is drawn to the housing by a substantially linear elastic body and attached to the ceiling speaker (housing). For this purpose, the housing is provided with a pair of through holes through which the elastic elastic body is inserted. The pair of through holes are provided at positions deviating from the above-described virtual plane. By providing a pair of through-holes at such a position, for example, the length of the casing due to the provision of the pair of through-holes as compared to the case where the pair of through-holes is provided on the virtual plane referred to here. An increase in the size is suppressed. Further, it is preferable that the pair of through holes are provided at positions inside the casing with respect to both end edges of a component element (for example, the first specific element) having the largest dimension in the width direction of the casing. By providing a pair of through holes at such a position, for example, compared to a case where the pair of through holes are provided at positions outside both end edges of the component element having the largest dimension in the width direction of the housing, An increase in the width dimension of the housing due to the provision of the pair of through holes is suppressed.

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

  By the way, an opening hole for exposing the sound emitting surface of the speaker unit to the outside of the casing is formed in the casing. A protruding wall that is provided along a part or all of the periphery of the opening hole and protrudes toward the outside of the housing along the direction along the central axis of the sound emitting surface of the speaker unit, It may be provided. When such a protruding wall is provided, the above-described pair of through-holes are provided through the portions other than the opening holes for the reverse phase sound emitted from the back side of the sound emitting surface of the speaker unit. In this case, it is possible to suppress the inconvenience that the sound emitted from the sound emitting surface is canceled by going around the sound emitting surface side of the speaker unit through the pair of through holes. As a result, the sound quality is improved.

  In addition, in a portion facing the back surface of the ceiling plate in the casing, the sound emitting surface is provided at a position outside the peripheral edge 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 protruding portion protruding toward the outside of the housing along the direction along the central axis of the surface may be further provided. That is, according to the present invention, the opening diameter of the mounting hole can be reduced as described above. However, the ceiling speaker of the present invention may be installed as an alternative to the conventional ceiling speaker 1, for example. It may be installed in a place where a mounting hole larger than necessary having a 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 fall through the mounting hole. In order to avoid this, the projecting portion referred to here is provided. In other words, the projecting portion engages with the mounting hole, thereby preventing the ceiling speaker of the present invention from falling through the mounting hole.

  Further, among the portions of the casing facing the back surface of the ceiling plate, the middle in the length direction of the casing may be narrowed to the inside of the casing in the width direction of the casing. In other words, a constriction in which the width dimension of the casing is narrowed may be provided midway in the length direction of the casing. By providing such a constriction, the installation work on the back of 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 greatly contributes to the reduction of the depth of the back of the ceiling where the ceiling speaker can be installed.

  Furthermore, in the present invention, a first terminal block and a second terminal block may be provided. Of these, the first terminal block includes a first normal terminal group including a plurality of first normal terminals, a first emergency terminal group including a plurality of first emergency terminals, a common terminal group including a plurality of common terminals, Have The second terminal block includes at least one second normal terminal connected to the first normal terminal group, at least one second emergency terminal connected to the first emergency terminal group, and A speaker input terminal group including a plurality of speaker input terminals. In addition, 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 disconnected from each other may be provided. One of the pair of input terminals of the speaker unit, for example, the anode input terminal, is connected to the 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, as will be described later, the connection with the external attenuator is particularly simplified, and the connection when the transition wiring is provided is also simplified.

  The first specific element in the present invention is, for example, a speaker speaker. And as said 2nd specific element, the matching transformer connected to the said speaker unit is contained, for example. In this case, the matching transformer is assumed to be arranged on either the first virtual plane or the second virtual plane.

  As described above, according to the present invention, a ceiling speaker that is smaller than the conventional one can be provided. Thereby, when the ceiling speaker of this invention is installed in the ceiling board, especially when a panel is attached, the designability of the indoor space containing the said ceiling improves more than before. Also, 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 necessary for the installation of recent downlights and emergency lighting equipment, and the work when providing these mounting holes Efficiency is improved. Furthermore, since it can be installed in a situation where the depth dimension of the back of the ceiling is small compared to the conventional case, the market is expected to expand.

It is a perspective view by CG of the ceiling speaker which concerns on one Embodiment of this invention. It is a perspective view by CG from the direction different from FIG. It is a perspective view by CG from a different direction from FIG. It is an external view by CG of the ceiling speaker. It is an external view by CG from the 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 by 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. FIG. 4 is a perspective view from the same direction as FIG. 3. 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 by which the cover in FIG. 12 was removed. It is an illustration figure which shows one state at the time of the installation work of the ceiling speaker. It is an illustration figure which shows the installation state of the same ceiling speaker. FIG. 17 is an illustrative view showing an installation strip of the ceiling speaker under an environment different from FIG. 16. It is a figure which shows the frequency characteristic of the ceiling speaker. It is a figure which shows the example of wiring of the conventional ceiling speaker as a comparison object of the ceiling speaker. It is a figure showing an example of wiring of a 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 wiring example different from FIG. 20 of the ceiling speaker which concerns on the same 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.

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

  First, FIGS. 1 to 3 show perspective views of the ceiling speaker 10 according to the present embodiment by CG from an appropriate direction. 4 and 5 are external views (six-face diagrams) of the ceiling speaker 10 by CG. Further, FIGS. 6 and 7 show a state where 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 in FIGS. Moreover, the external view from the same direction as FIG. 4 and FIG. 5 is shown in FIG. 11 and FIG. 13 and 14 show a state where the cover 16 in FIGS. 11 and 12 is removed. In addition, in FIGS. 8-14, considering these easiness, the R part which is not originally represented by a diagram is also represented by a diagram appropriately.

  As can be seen with reference to FIGS. 1 to 14, the ceiling speaker 10 according to the present embodiment includes 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 plate-like base 20 on which components including the speaker unit 14 are mounted, and the above-described cover 12 that covers 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 hole 20a is provided so that the center thereof is located at the center in the short 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 hole 20a is provided with a protective strip 20b having an appropriate shape for protecting the sound emitting surface 14a of the speaker unit 14, for example, having a mesh shape. Of the protective strip 20b, a linear portion 20c that passes through the center of the opening hole 20a and extends 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. Similarly, two portions 20d and 20d of the protective strip 20b that are adjacent to the rib 20c with the rib 20c sandwiched in the short direction of the base 20 and are convexly curved toward the rib 20c are also the base. It has an appropriate dimension in the thickness direction of 20, that is, functions as a rib. Furthermore, portions 20e and 20e excluding a part of the peripheral edge of the opening hole 20a, specifically, a portion in contact with both 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 a rib shape.

  Here, for example, it is assumed that the longitudinal direction of the base 20 is the length direction of the ceiling speaker 10 including the base 20. 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. Then, it is slightly closer to one end than the center in the length direction of the base 20 and at the center in the width direction of the base 20, that is, approximately at the center in each of the length direction and the width direction of the base 20, The speaker unit 14 is located. The speaker unit 14 has the largest height dimension among the components mounted on the base 20, and the dimension in the length direction and the width direction of the base 20 is also the largest.

  In addition to the speaker unit 14, parts having large dimensions include a matching transformer 16 and an attenuator auto-transformer 22 as parts having particularly large height dimensions. Among them, the matching transformer 16 is disposed between the speaker unit 14 and one end edge of the base 20 on the side where the speaker unit 14 is slightly offset in the length direction of the base 20. It is arranged as close to the speaker unit 14 as possible. In the width direction of the base 20, the matching transformer 16 is arranged at the center in the width direction, that is, a virtual axis 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. Are arranged on the plane. Furthermore, the direction of the matching transformer 16 itself is also determined. That is, the matching transformer 16 includes a hollow iron core 16a having a substantially rectangular parallelepiped shape and a winding 16b wound around the iron core 16a. The matching transformer 16 employed here has an iron core 16a. The height dimension of the portion is larger than the height dimension of the winding 16b portion. In order to reduce the size of the entire ceiling speaker 10 including the cover 12 which will be described in detail later, the matching transformer 16 is configured such that the dimension of the iron core 16a is shortened in the length direction of the ceiling speaker 10 (base 20). In this case, the opening of the hollow portion of the iron core 16a (the space around which the winding wire 16b is wound) is arranged in such a direction as to be orthogonal to the length direction of the ceiling speaker 10.

  On the other hand, the autotransformer 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-described virtual plane that includes the central axis of the sound emitting surface 14 a of the speaker unit 14 and extends along the length direction of the base 20. The autotransformer 22 is arranged as close to the speaker unit 14 as possible. Further, like the matching transformer 16, the auto transformer 22 has its own orientation. That is, the autotransformer 22 has a substantially rectangular parallelepiped hollow iron core 22a and a winding 22b wound around the iron core 22a. With respect to the autotransformer 22 employed here, the iron core The height dimension of the 22a portion is larger than the height dimension of the winding 22b portion. The autotransformer 22 is oriented in such a way that the dimension of the iron core 22a is shortened in the length direction of the ceiling speaker 10, that is, here the opening of the hollow portion of the iron core 22a (the space around which the winding wire 22b is wound). Are arranged in a direction orthogonal to the length direction of the ceiling speaker 10.

  Further, two terminal blocks 24 and 26 to which appropriate wirings are connected are provided at the edge portion of the base 20 on the side where the autotransformer 22 is disposed. These terminal blocks 24 and 26 are mounted on a printed wiring board 28 common to the autotransformer 22. The matching transformer 16 described above is mounted on another printed wiring board 30. In other words, the matching transformer 16 and the auto transformer 22 are purposely mounted on separate printed wiring boards 28 and 30 so that the matching transformer 16 and the auto transformer 22 are arranged in a row with the speaker unit 14 in between. ing.

  Other parts are smaller than the speaker unit 14, the matching transformer 16, and the autotransformer 22, and are arranged at appropriate positions. Specifically, the parts are appropriately mounted on the two printed wiring boards 28 and 30. Yes. However, each component is arranged as close as possible to the speaker unit 14 in the length direction of the base 20. Thereby, the size of the entire ceiling speaker 10 including the base 20 in the length direction of the base 20, that is, the length dimension is reduced. Further, in the width direction of the base 20, each component is disposed so as to be located inside the base 20 with respect to both end edges of the speaker unit 14. Thus, the overall size of the ceiling speaker 10 including the base 20 in the width direction of the base 20, that is, the width size is reduced.

  Then, the cover 12 is attached to the base 20 so as to cover each component including the speaker unit 14 mounted on the base 20, and is specifically screwed. The cover 12 has a substantially quadrangular truncated pyramid shape with a portion covering the speaker unit 14 having the largest height among the components mounted on the base 20 as an upper base. The size of the speaker itself is reduced (in other words, slimming down), and the ceiling speaker 10 is reduced in size. However, a portion 12 a of the case 12 that covers the matching transformer 16 is formed in a substantially rectangular parallelepiped shape so as to match the outer shape of the matching transformer 16. Further, the corners of the rectangular parallelepiped portion 12a are chamfered, and particularly the corners located on the end side (the side away from the speaker unit 14) of the ceiling speaker 10 are matched with the matching transformer 16. The chamfered shape is larger depending on the shape (step) of the iron core 16a and the winding 16b described above. Similarly, the portion 12b of the case 12 that covers the auto transformer 22 is also formed in a substantially rectangular parallelepiped shape so as to match the outer shape of the auto transformer 22. The corners of the rectangular parallelepiped portion 12b are also chamfered, and in particular, the corners located on the end side (the side away from the speaker unit 14) of the ceiling speaker 10 are the autotransformer 22. The chamfered shape is larger depending on the shape of the iron core 22a and the winding wire 22b. In addition, a triangular arrow 12c indicating a direction when the ceiling speaker 10 is installed in a manner described later is integrally formed with the rectangular parallelepiped portion 12b (cover 12) at a portion corresponding to the upper surface of the rectangular parallelepiped portion 12b. Yes.

  Furthermore, a substantially concave elongated restraining groove 12d for restraining a spring coil as a stretchable elastic body (not shown) used for mounting a panel (not shown) is provided on the outer surface of the cover 12. Specifically, the constraining groove 12d passes through the central axis of the sound emitting surface 14a of the speaker unit 14 and extends in an oblique direction with respect to each of the length direction and the width direction of the ceiling speaker 10. , Provided. In addition, a pair of through-holes 12e and 12f into which both ends of the spring coil are inserted separately are provided in the vicinity of the portions of the cover 12 that correspond to both ends of the restraining groove 12d. That is, the pair of through-holes 12e and 12f includes a center axis of the sound emitting surface 14a of the speaker unit 14 and a position deviating from the above-described virtual plane along the length direction of the cover 12 (base 20). The cover 12 is provided at a position inside the cover 12 relative to 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 also provided at positions corresponding to the through holes 12e and 12f of the base 20. By providing these through holes 12e, 12f, 20f, and 20g at such positions, for example, the through holes 12e, 12f, 20f, and 20g are compared with the case where the through holes 12e, 12f, 20f, and 20g are provided on the virtual plane referred to here. By providing the holes 12e, 12f, 20f and 20g, an increase in the length dimension of the case 18 is suppressed, and as a result, an increase in the overall length dimension of the ceiling speaker 10 is suppressed. In addition, for example, the through holes 12e, 12f, 20f, and 20g are compared with the case where the through holes 12e, 12f, 20f, and 20g are provided at positions outside the both end edges of the speaker unit 14 in the width direction of the case 18. The increase in the width dimension of the case 18 due to being provided is suppressed, and as a result, the increase in the width dimension of the entire ceiling speaker 10 is suppressed.

  Here, when attention is paid again to the base 20, a ceiling speaker 10 including the base 20 is screwed to a ceiling plate 100 to be described later in the vicinity of the pair of through holes 20 f and 20 g in the base 20 as necessary. 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, two projecting portions 20j and 20k are provided on one side edge of the base 20 so as to project toward the side opposite to the side to which the case 12 is attached, that is, toward the lower side. These protrusions 20j and 20k are provided such that the edge portions thereof are located outward from the peripheral edge of the sound emitting surface 14a in the radial direction of the central axis of the sound emitting surface 14a of the speaker unit 14. Also, the same two protruding portions 20n and 20p are provided on the other side edge of the base 20.

  In addition, the width dimension of the base 20 is narrowed in the middle part in the length direction of the base 20, for example, the part where the speaker unit 14 is located, so to speak, curved constrictions 20q and 20q are provided. Yes. Further, in the portion where the constrictions 20q and 20q are provided, the above-described protruding portions 20j, 20k, 20n and 20p are not provided, that is, the thickness of both side edges of the base 20 is suppressed. Yes.

  And the wire winding hole 20r by which the wire for preventing the fall of the ceiling speaker 10 is wound is provided in the appropriate position of the base 20, for example, the appropriate position near one side edge of the said base 20. Yes. Accordingly, the cover 12 is provided with an appropriate notch 12i so that the wire can be wound around the wire winding hole 20r.

  Each of the above-described components includes a plurality of, for example, four switches, and the base 20 is for operating these four switches, in other words, operation knobs 32a and 32b for the four switches. , 32c and 32d are provided with four through holes 20s, 20t, 20u and 20v for exposing the cover 18 to the outside.

  When attention is paid again to the cover 12, the cover 12 is provided with heat radiation holes 12j, 12j,.

  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 with 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 through a circular mounting hole 100a provided in the ceiling plate 100. That is, the ceiling speaker 10 is inserted into the back of the ceiling. At this time, the ceiling speaker 1 is inserted into the mounting hole 100a from the end side where the two terminal blocks 24 and 26 are provided, that is, according to the direction indicated by the triangular arrow 12c described above.

  Here, when the state shown in FIG. 15A is viewed from the front of the ceiling speaker 10, it is as shown in FIG. As can be seen from FIG. 15B, when the ceiling speaker 10 is inserted obliquely into the circular mounting hole 100a, the mounting hole 100a becomes a flat oval shape for the ceiling speaker 10. This is an obstacle in the installation work of the ceiling speaker 100a. However, since the ceiling speaker 10 (base 20) is provided with the constrictions 20q and 20q as described above, the ceiling speaker 10 and the mounting hole 100a are correspondingly provided. A margin is generated between the ceiling speaker 10 and the installation work of the ceiling speaker 10 is facilitated. Moreover, since the ceiling speaker 10 (cover 12) is formed in a substantially quadrangular pyramid as described above, this also facilitates the installation work of the ceiling speaker 10.

  Then, after the ceiling speaker 10 is inserted (passed) through the mounting hole 100a, the ceiling speaker 10 is placed on the back of the ceiling as shown in FIG. That is, the ceiling speaker 10 is installed so that the sound emitting surface 14a of the speaker unit 14 is exposed to the surface side of the ceiling plate 100 through the mounting hole 100a. At this time, the ceiling speaker 10 is installed in a state where the tips (lower ends) of the four protrusions 20j, 20k, 20n and 20p described above are in contact with the back surface (upper surface) of the ceiling plate 100. Thereafter, as in the conventional case, hooks 34 and 34 provided at both ends of a spring coil (not shown) are locked to corresponding hook locking portions of a 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). Therefore, the length L of the ceiling speaker 10 is L = 180 mm. The width dimension W of the ceiling speaker 10 is W = 80 mm, that is, the same as the 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 of the present embodiment is much smaller than the conventional ceiling speaker 1 described above, and is downsized by about 50%. The reason why the speaker unit 14 with an aperture of 80 mm is adopted is to satisfy the standard of L class with 1 W input in consideration of cost (profit), and this is about this This is because a caliber having a diameter of 5 mm is required.

  In order to install such a small ceiling speaker 10 of the present embodiment on the back of the ceiling in the manner described above, it is sufficient if the opening diameter Φ of the mounting hole 100a provided in the ceiling plate 100 is Φ = 100 mm. The opening diameter Φ of Φ = 100 mm is sufficient not only because the ceiling speaker 10 is downsized, but also that the ceiling speaker 10 is provided with the constrictions 20q and 20q as described above, and the ceiling speaker 10 The fact that the outer shape of the (cover 12) is substantially a square pyramid also greatly contributes. Of course, the opening diameter Φ of the mounting hole 100a is smaller than the length L of the ceiling speaker 10 (Φ <L) and larger than the width W of the ceiling speaker 10 (Φ> W). It is larger than the height dimension H of the ceiling speaker 10 (Φ> H).

  The opening diameter Φ of the mounting hole 100a of Φ = 100 mm is the same as the opening diameter of the mounting hole necessary for the installation of recent downlights and emergency lighting equipment. Therefore, it is possible to improve the working efficiency when providing the mounting holes for downlights and emergency lighting equipment, including the mounting holes 100a for the ceiling speaker 10. Moreover, since the opening diameter (PHI) of the attachment hole 100a is small in this way, the outer diameter of the panel which covers this also becomes small, and the designability when the ceiling speaker 10 including the said panel is installed improves compared with the past. .

  Furthermore, the depth dimension A of the ceiling is sufficient if A = 70 mm or more. On the other hand, the conventional ceiling speaker 1 requires a depth dimension A ′ of A ′ = 130 mm or more as described above. Therefore, compared with the conventional ceiling speaker 1, the ceiling speaker 10 according to the present embodiment has the following dimensions. For example, the number of scenes that can be installed is expanded and the market is expected to expand.

  In addition, the ceiling speaker 10 of the present embodiment can be installed as an alternative to the conventional ceiling speaker 1, for example. In this case, since the ceiling speaker 10 of this embodiment is attached to the attachment hole 100a having the opening diameter Φ of Φ = 150 mm, depending on the installation situation (position) of the ceiling speaker 10, the ceiling speaker 10 may be attached to the attachment hole 100a. There is concern about falling through 100a. However, the ceiling speaker 10 of 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 with the hole 100a, the ceiling speaker 10 can be prevented from falling through the mounting hole 100a. The distance C between the edges of the projecting portions 20j and 20k (or 20k and 20n) in the length direction of the ceiling speaker 10 is set to 134 mm, for example.

  In addition, according to the ceiling speaker 10 of the present embodiment, the arc-shaped ribs 20e and 20e are provided so as to surround the periphery of the opening hole 20a for exposing the sound emitting surface 14a of the speaker unit 14. Sound quality is improved. That is, sound is emitted from the front side of the radiation surface 14a of the speaker unit 14, but at the same time, sound having an opposite phase is emitted from the back side of the radiation surface 14a. Then, the sound in the opposite phase wraps around the sound emitting surface 14a through a portion other than the opening hole 20a, particularly through a pair of through holes 20f and 20g provided in the base 20 for inserting the spring coil. Thus, there is a concern that the sound emitted from the sound emitting surface 14a may be canceled out. However, by providing the arc-shaped ribs 20e and 20e, the arc-shaped ribs 20e and 20e are interposed between the pair of opening holes 20f and 20g and the opening hole 20a (that is, such positions). Therefore, the wraparound of the sound with the opposite phase is suppressed, and the sound quality is improved.

  FIG. 18 shows frequency characteristics when the arc-shaped ribs 20e and 20e are provided and when the arc-shaped ribs 20e and 20e are not provided. In FIG. 18, the thick solid curve α indicates the frequency characteristics when the arc-shaped ribs 20e and 20e are provided, and the thick dashed curve β indicates that the arc-shaped ribs 20e and 20e are provided. The frequency characteristics when there is no data are shown. As can be seen from FIG. 18, the arc-shaped ribs 20e and 20e are provided in the case where the arc-shaped ribs 20e and 20e are provided in a frequency band lower than about 1 kHz. A sound pressure level higher by 1 dB or more can be obtained than in the case where there is no sound. This means that it contributes to an increase in the sound pressure level in the frequency band of the voice warning sound second signal. In particular, although the small speaker unit 14 of 80 mm is employed, 1 W as described above. Is very effective in satisfying the criterion of class L. On the other hand, in the frequency band higher than 1 kHz, there is no particular difference between the case where the arc-shaped ribs 20e and 20e are provided and the case where the arc-shaped ribs 20e and 20e are not provided. In other words, there is no inconvenience due to the provision of the arc-shaped ribs 20e and 20e. As described above, since the arc-shaped ribs 20e and 20e are provided, the sound quality is improved, so that not only emergency broadcasting but also business broadcasting can be realized. Note that the boundary frequency, which is approximately 1 kHz here, is determined by the shape and size (capacity) of the case 18.

  The contents described in this embodiment are specific examples of the present invention and do not limit the scope of the present invention.

  For example, a dynamic type speaker having a diameter of 80 mm is adopted as the speaker unit 14, but a dynamic type having a size other than this may be adopted. In this case, as a matter of course, the size of the ceiling speaker 10 as a whole and the shape may change depending on the size of the speaker unit 14 including the aperture. A speaker other than the dynamic type may be adopted as the speaker unit 14.

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

  By the way, in the above-mentioned conventional ceiling speaker 1, the attenuator is not particularly mounted, and in the type using an external attenuator, the wiring to the terminal blocks 6 and 7 is complicated, which causes a connection error. Another problem is easy. According to the ceiling speaker 10 of this embodiment, the device for solving this problem is also given.

  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) terminals 6a, 6a and 6a, and three R (URGENCY) terminals 6b, 6b and 6b. Three COM (COMMON: common) terminals 6c, 6c and 6c are provided. 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 7a and 7a and two SP-COM (SPEAKER COMMON: cathode). 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. Strictly speaking, the above-described matching transformer is provided on the input side of the speaker unit 2. However, for convenience of explanation, the illustration of the matching transformer is omitted here. Further, the SP-COM terminals 7b and 7b of the speaker input terminal 7 are connected to the COM terminals 6c, 6c and 6c of the relay terminal 6, respectively.

  When the conventional ceiling speaker 1 having the relay terminal 6 and the speaker input terminal 7 is applied to a three-wire speaker line, the N lines 50a and R of the wiring 50 (from an amplifier (not shown)) of the trunk line are used. Line 50b and COM line 50c are connected to N terminal 6a, R terminal 6b and COM terminal 6c of relay terminal 6, respectively. Similarly, the N line 52a, R line 52b, and COM line 52c of the feed wiring 52 to the main line (to other speakers not shown) are respectively connected 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) terminal 70c. Among these, the N terminal 70 a is connected to the N terminal 6 a of the relay terminal 6 of the ceiling speaker 1 through 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. Further, 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 through the SP line 54 c of the attenuator connection wiring 54.

  As can be seen from the configuration in FIG. 19, the main lines 50 and 52 including the feed wiring 52 need only be connected to the relay terminal 6. 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 and is complicated. For this reason, it is easy to cause a connection mistake.

  On the other hand, each terminal block 24 and 26 of the ceiling speaker 10 of this embodiment is configured as shown in FIG. That is, one terminal block 24 as the first terminal block is a speaker input / relay terminal, which functions as a relay terminal and also functions as a part of the speaker input terminal, and is the three N terminals 24a. , 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 terminal 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 above-described printed wiring board 28. 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 26c and 26c 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 the COM terminals 24c, 24c and 24cb of the speaker input / relay terminal 24. Strictly speaking, a matching transformer 16 is provided on the input side of the speaker unit 14, but the illustration of the matching transformer 16 is also 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 two are connected (ON) and not connected (OFF). For example, a slide-type manual switch 36 is provided as a switching means for selectively switching between the state and the state. The manual switch 36 is operated by one of the four operation knobs 32a, 32b, 32c and 32d described above. In other words, the operation knob 32 a is attached to the manual switch 36.

  In the case where the ceiling speaker 10 of the present embodiment including the 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 are used. And COM line 50c are connected to N terminal 24a, R terminal 24b and COM terminal 24c of speaker input / relay terminal 24, respectively. Similarly, the N line 52a, R line 52b and 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. As for the external attenuator 70, its N terminal 70a, R terminal 70b and SP terminal 70c are connected to the attenuator connection terminal of the ceiling speaker 10 via the N line 54a, R line 54b and SP line 54c of the attenuator connection wiring 54, respectively. 26 are connected to N terminal 26a, R terminal 26b and SP terminal 26c. Furthermore, it is also possible to provide a branch wiring 56 as a third wiring that can be handled in the same manner as the feed wiring 52 (in other words, can perform the same function as the feed wiring 52). That is, the N line 56a, R line 56b, and 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, the main lines 50 and 52 including the feed wiring 52 need only be connected to the speaker input / relay terminal 24. 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 exactly the same as the connection to the external attenuator 70. Therefore, the wiring is extremely simple compared to the conventional ceiling speaker 1, and therefore, connection mistakes can be prevented. Furthermore, since the branch wiring 56 can be provided, it is possible to flexibly cope with the environment (the size of the indoor space, the layout, etc.) in which the ceiling speaker 10 is installed. In the configuration shown in FIG. 20, the manual switch 36 is turned off.

  Further, a configuration in which the transition wiring 58 is provided will be considered. First, as shown in FIG. 21, in the conventional ceiling speaker 1 (SP1 ′), the SP-HOT line 58a of the transition wiring 58 is connected to the SP-HOT terminal 7a of the speaker input terminal 7 as shown in FIG. At the same time, the SP-COM line 58 c of the transition wiring 58 is connected to the SP-COM terminal 7 b of the speaker input terminal 7. In general, as the crossover wiring 58, a three-wire (three-core) cable having the same specifications as the trunk line 50 or the like is laid, so that one line (R line) 58b is left over. Therefore, it is necessary to perform end processing for insulating the end of the remaining line 58b. Then, in the ceiling speaker 1 (SP2 ′) as the transfer destination, the SP-HOT line 58a of the transition wiring 58 is connected to the SP-HOT terminal 7a of the speaker input terminal 7, and the SP of the speaker input terminal 7 is also connected. The SP-COM line 58c of the transition wiring 58 is connected to the -COM terminal 7b. Even at this transfer destination, since one line 58b of the transfer wiring 58 is left, it is necessary to perform terminal processing of the remaining line 58b.

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

  However, in the conventional configuration shown in FIG. 21, no wiring is connected to the relay terminal 6 of the ceiling speaker 1 (SP2 ') as the transfer destination. At first glance, it seems that the wiring to the destination ceiling speaker 1 (SP2 ') is inappropriate (in other words, misunderstood), and from this, the destination ceiling speaker 1 ( Incorrect wiring may be made to the relay terminal 6 of SP2 ′), that is, a connection error may occur. Further, it is necessary to perform the end processing of the surplus line 58c as described above at each of the transfer source and the transfer destination, and this work 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) as the transfer source, the SP of the transition wiring 58 is connected to the SP terminal 26c of the attenuator connection terminal 26. -The HOT line 58a is connected. In the ceiling speaker 10 (SP1) as the transfer source, the R line 58b of the transition wiring 58 is connected to the R terminal 24b of the speaker input / relay terminal 24, and the COM terminal of the speaker input / relay terminal 24 is connected. The SP-COM line 58c of the crossover wiring 58 is connected to 24c. On the other hand, in the ceiling speaker 10 (SP2) as the transfer destination, the SP-HOT line 58a, the R line 58b and the N line 24a, the R terminal 24b and the COM terminal 24c of the speaker input / relay terminal 24 are connected to the N terminal 24a, the R terminal 24b and the COM terminal 24c, respectively. A COM line 58c is connected. Note that the manual switch 36 of the ceiling speaker 10 (SP1) as the transfer source is turned off. Then, the manual switch 36 of the destination ceiling speaker 10 (SP2) is turned on.

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

  In the configuration shown in FIG. 22, when attention is paid to the ceiling speaker 10 (SP2) as the delivery destination, the SP-HOT line 58a of the transition wiring 58 connected to the N terminal 24a of the speaker input / relay terminal 24 is replaced with the N line. As a result, the connection of the crossover wiring 58 to the speaker input / relay terminal 24 is the same as the connection of the trunk line 50 or the like to the speaker input / relay terminal 24 of the ceiling speaker 10 (SP1) as the transfer source. In other words, it seems that the delivery destination speaker 10 (SP2) may be wired in the same manner as the delivery source speaker 10 (SP1). As a result, connection errors can be prevented. It should be noted that the R line 58b of the crossover wiring 58 has no significant effect electrically (no meaning), but is significant in that it contributes to prevention of connection errors.

  As described above, according to the ceiling speaker 10 of the present embodiment, in addition to realizing the miniaturization, it is possible to prevent connection mistakes during wiring. Note that the three types of terminals 24a, 24b, and 24c constituting the speaker input / relay terminal 24 are not limited to three (especially, if the space including the size of the case 18 is allowed), the other terminals A number may be provided.

10 Ceiling speaker 12 Cover 14 Speaker unit 16 Matching transformer 18 Case 20 Base 22 Autotransformer

Claims (10)

In the ceiling speaker installed on the back surface side of the ceiling panel so that the sound emitting surface of the speaker unit is exposed to the front surface side of the ceiling panel through the mounting holes provided in the ceiling panel,
A housing for accommodating a plurality of component elements including the speaker unit;
The dimensions of the casing in a first direction orthogonal to the central axis of the sound emitting surface of the speaker unit are the dimensions of the casing in a second direction orthogonal to the central axis of the sound emitting surface and the first direction, respectively. Bigger than
The first specific element having the largest dimension in the direction along the central axis of the sound emitting surface among the plurality of component elements is disposed at substantially the center in each of the first direction and the second direction inside the housing. A second specific element different from the first specific element among the plurality of component elements is disposed on a virtual plane including the central axis of the sound emitting surface and along the first direction;
Features a ceiling speaker. The virtual plane includes a first virtual plane between one end of the housing and the first specific element in the first direction, the other end of the first direction in the first direction, and the first specific. A second virtual plane between the elements,
The second specific element is disposed on at least one of the first virtual plane and the second virtual plane,
The ceiling speaker according to claim 1. The first specific element has the largest dimension in the second direction among the plurality of component elements,
The second specific element is located inside the housing in the second direction with respect to both end edges of the first specific element;
The ceiling speaker according to claim 1. A pair of through-holes through which a substantially linear elastic body 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 into the housing. Provided in the housing,
The pair of through holes are provided at positions deviating from the virtual plane.
The ceiling speaker according to claim 1. A pair of through-holes through which a substantially linear elastic body 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 into the housing. Provided in the housing,
One of the pair of through holes is provided at one end side of the housing in the second direction at a position deviating from the first virtual plane,
The other of the pair of through holes is provided on the other end side of the housing in the second direction at a position deviating from the second virtual plane.
The ceiling speaker according to claim 2. In order to expose the sound emitting surface to the outside of the housing, the sound emitting surface is provided along a part or all of the peripheral edge of the opening hole formed in the housing, along the direction along the central axis of the sound emitting surface. A protruding wall protruding toward the outside of the housing;
The ceiling speaker according to claim 1. A direction along the central axis of the sound emitting surface provided at a position outward from the periphery of the sound emitting surface in the radial direction of the central axis of the sound emitting surface at a portion facing the back surface of the ceiling plate in the casing Further including a protruding portion protruding toward the outside of the housing along
The ceiling speaker according to claim 1. Of the portion facing the back surface of the ceiling plate in the casing, the middle in the first direction is narrowed to the inside of the casing in the second direction.
The ceiling speaker according to claim 1. A first terminal block and a second terminal block;
The first terminal block includes 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 connected to the first normal terminal group, and at least one second emergency terminal connected to the first emergency terminal group. A speaker input terminal group including a plurality of speaker input terminals, and
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 the speaker input terminal group is 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;
The ceiling speaker according to claim 1. In the ceiling speaker installed on the back surface side of the ceiling panel so that the sound emitting surface of the speaker unit is exposed to the front surface side of the ceiling panel through the mounting holes provided in the ceiling panel,
A housing for accommodating a plurality of component elements including the speaker unit;
The dimensions of the casing in a first direction orthogonal to the central axis of the sound emitting surface of the speaker unit are the dimensions of the casing in a second direction orthogonal to the central axis of the sound emitting surface and the first direction, respectively. Bigger than
The speaker unit is disposed approximately at the center in each of the first direction and the second direction inside the housing,
The matching transformer connected to the speaker unit is on a virtual plane including the central axis of the sound emitting surface and along the first direction, and the housing in the first direction of the virtual plane On a first virtual plane between one end of the speaker and the speaker unit, and on a second virtual plane between the other end of the housing and the speaker unit in the first direction of the virtual plane. , Being placed in either
Features a ceiling speaker.