Explosion-proof sound post

Abstract

The invention relates to an explosion-proof sound post comprising a shell; the explosion-proof loudspeaker comprises a lower cover and an upper cover which are mutually spliced to form a cavity, and a loudspeaker unit arranged in the cavity, the edge of the upper cover is provided with a first step which forms a first spigot explosion-proof surface with the lower cover, and the bottom surface of the lower cover is provided with a cable hole penetrating through the bottom surface; the explosion-proof hardware cavity comprises a hardware cavity lower cover, a hardware cavity upper cover and a hardware cavity top cover, the hardware cavity lower cover and the hardware cavity upper cover are in butt joint to form a hollow cavity, the hardware cavity top cover covers the hardware cavity upper cover in a sealing mode, the edge of the hardware cavity top cover is provided with a step part, a fourth spigot explosion-proof face is formed by the hardware cavity top cover and the step part, and the hardware cavity top cover is provided with a hardware cavity cable hole penetrating through the hardware cavity top cover; the horn unit of each explosion-proof loudspeaker is electrically connected with the circuit board in the hollow cavity through a cable, the first end of the cable is arranged in the cable hole through the first stuffing box, and the second end of the cable is arranged in the cable hole of the hardware cavity through the second stuffing box.

Description

Technical Field

[0001] The present application relates to the technical field of loudspeaker equipment, and in particular to an explosion-proof sound column. Background Art

[0002] Loudspeakers are a type of broadcasting sound source, and are mainly used in shopping malls, industrial parks, squares and other places. The explosion-proof sound columns currently on the market that are specifically used in flammable and explosive workplaces still have shortcomings. The output sound is not clear, especially when used in special high-noise environments. The sound is almost inaudible, and the sound penetration is not strong, and the propagation distance is not far enough, making it difficult to achieve the ideal sound transmission effect. The main reason for this problem is that the sound-emitting part of the explosion-proof sound column used for sound transmission usually needs to be reduced in area to meet the explosion-proof performance. Therefore, how to balance the explosion-proof performance and sound transmission effect is a key issue that needs to be urgently solved for explosion-proof sound columns. Summary of the invention

[0003] The embodiments of the present application provide an explosion-proof sound column, in which the speaker unit and the hardware unit are designed to have independent explosion-proof cavities, so the shell of the speaker sound column does not need to have an explosion-proof structure. This split-cavity design that miniaturizes the explosion-proof structure can not only reduce the manufacturing requirements of the explosion-proof structure, but also improve the sound transmission effect through miniaturization.

[0004] In one embodiment of the present application, there is provided an explosion-proof sound column, comprising: A housing, the housing comprising a mesh panel and a mounting plate mounted on an inner side of the mesh panel; At least one explosion-proof speaker, the explosion-proof speaker is installed on the mounting plate, the explosion-proof speaker comprises a lower cover and an upper cover which are assembled to form a cavity, and a speaker unit installed in the cavity, the edge of the upper cover has a first step which forms a first stop flameproof surface with the lower cover, and the bottom surface of the lower cover has a cable hole which passes through the bottom surface; An explosion-proof hardware cavity, the explosion-proof hardware cavity is installed in the shell, the explosion-proof hardware cavity comprises a hardware cavity lower cover and a hardware cavity upper cover which are connected to each other to form a hollow cavity, and a hardware cavity top cover which covers the hardware cavity upper cover, the edge of the hardware cavity top cover has a step portion which forms a fourth stop flameproof surface with the hardware cavity upper cover, and the hardware cavity top cover has a hardware cavity cable hole which passes through the hardware cavity top cover; Wherein, the speaker unit of each explosion-proof speaker is electrically connected to the circuit board in the hollow cavity via a cable, the first end of the cable is installed in the cable hole via a first stuffing box, and the second end is installed in the cable hole of the hardware cavity via a second stuffing box, the first stuffing box has a third step that forms a third stop explosion-proof surface with the cable hole, and the second stuffing box and the hardware cavity cable hole form a fifth stop explosion-proof surface.

[0005] In one embodiment, the cavity defines an axial direction perpendicular to the bottom surface and a radial direction perpendicular to the axial direction, wherein the axial direction is perpendicular to the mounting plate; The first stop flameproof surface, the third stop flameproof surface, the fourth stop flameproof surface, and the fifth stop flameproof surface all extend along the axial direction.

[0006] In one embodiment, the first stuffing box has a second stuffing material wrapped around the cable, and the first stuffing box is fixed to the cable hole via a first compression nut; The second stuffing box has a fourth filling material for wrapping the cable therein, and the second stuffing box is fixed to the cable hole of the hardware cavity via a second compression nut.

[0007] In one embodiment, the edge of the hardware cavity upper cover has a first flange protruding toward the hardware cavity lower cover, and the edge of the hardware cavity lower cover has a first groove to accommodate the first flange, and the first groove is filled with a third filler to fill the gap between the first flange and the first groove.

[0008] In one embodiment, the upper cover has an annular side wall extending along the axial direction, and the annular side wall extends from the inner surface of the upper cover away from the bottom surface; The explosion-proof speaker comprises: a top cover, the top cover closing a port of the annular side wall facing away from the bottom surface; The top cover has a sound-generating portion penetrating the top cover along the axial direction, the first metal sintered block covers the sound-generating portion from the inside, the inner surface of the top cover has a first mounting groove surrounding the sound-generating portion, the edge of the first metal sintered block is fixedly mounted in the first mounting groove via a first filler, and the first filler fills a gap between the first metal sintered block and the first mounting groove; The cavity is divided by the speaker unit into a rear cavity formed by the lower cover and a front cavity formed by the annular side wall and the top cover; The edge of the top cover has a second step which forms a second stop flameproof surface with the annular side wall, and the second stop flameproof surface extends along the axial direction.

[0009] In one embodiment, the cavity has a sound-emitting portion penetrating the upper cover, the inner surface of the upper cover has a first mounting groove surrounding the sound-emitting portion, the first metal sintered block covers the sound-emitting portion from the inside, the edge of the first metal sintered block is fixedly installed in the first mounting groove via a first filler, and the first filler fills the gap between the first metal sintered block and the first mounting groove; The speaker unit is formed as a horn tube, the horn mouth of the horn tube fixes the first metal sintered block in the first installation groove, and the horn mouth of the horn tube abuts against the inner surface of the first metal sintered block.

[0010] In one embodiment, the upper cover has a first annular side wall and a second annular side wall extending in the axial direction, the first annular side wall surrounds the second annular side wall from the outside, and the front edge of the first annular side wall is further away from the bottom surface than the front edge of the second annular side wall; The leading edge of the first annular side wall is fixed to the mounting plate; The front edge of the second annular sidewall has a sound-generating portion connected to the cavity, the first metal sintered block covers the sound-generating portion from the inside, and the sixth filler fills the gap between the outer edge of the first metal sintered block and the second annular sidewall.

[0011] In one embodiment, the bottom surface has an air leakage hole penetrating the bottom surface, the second metal sintered block covers the air leakage hole from the inside, and the waterproof breathable membrane is isolated between the air leakage hole and the second metal sintered block; The cavity has a second mounting groove surrounding the air leakage hole, and the edge of the second metal sintered block is fixedly installed in the second mounting groove via a second filler, and the second filler fills the gap between the second metal sintered block and the second mounting groove.

[0012] In one embodiment, the bottom surface has an inspection hole penetrating the bottom surface, and the inspection hole is closed from the outside by a plug.

[0013] In one embodiment, the explosion-proof hardware chamber comprises: An external cable hole, the external cable hole passing through the lower cover of the hardware cavity, the external cable hole having a hole wall protruding from the lower cover of the hardware cavity and passing through the shell; The external cable is electrically connected to the circuit board in the hollow cavity via the external cable hole. The external cable hole contains a fifth filler that wraps the external cable. The hole wall is fixed to the shell via a third clamping nut.

[0014] In this example, the airtightness of the explosion-proof speaker cavity ensures the sound transmission effect and explosion-proof performance of the speaker, the airtightness of the hollow cavity of the explosion-proof hardware cavity ensures the explosion-proof performance, the internal connecting cables are designed as separate explosion-proof structural parts, and the speaker unit and the hardware unit are designed to have independent explosion-proof cavities. The outer shell of the speaker column does not need to have an explosion-proof structure. This miniaturized chamber design of the explosion-proof structure can not only reduce the manufacturing requirements of the explosion-proof structure, but also reduce the volume of the speaker cavity with explosion-proof performance. The sound transmission effect of the speaker is far better than that of the speaker column with an overall shell designed as an explosion-proof structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following drawings are only used to illustrate and explain the present application, and do not limit the scope of the present application.

[0016] Figure 1 This is a schematic diagram of the explosion of the explosion-proof sound column of the present application.

[0017] Figure 2 This is a schematic diagram of the explosion of the explosion-proof sound column of the present application.

[0018] Figure 3 This is a schematic diagram of the structure of the hardware cavity in the explosion-proof sound column of the present application.

[0019] Figure 4 This is a schematic diagram of the structure of the hardware cavity in the explosion-proof sound column of the present application.

[0020] Figure 5 This is a schematic structural diagram of the first embodiment of the explosion-proof loudspeaker in this application.

[0021] Figure 6 This is a schematic structural diagram of the second embodiment of the explosion-proof loudspeaker in the present application.

[0022] Figure 7 It is a schematic structural diagram of the third embodiment of the explosion-proof loudspeaker in the present application. DETAILED DESCRIPTION

[0023] In order to have a clearer understanding of the technical features, purposes and effects of the invention, the specific embodiments of the invention are now described with reference to the accompanying drawings, in which the same reference numerals represent the same parts.

[0024] In this document, “exemplary” means “serving as an example, instance or illustration”, and any diagram or implementation described in this document as “exemplary” should not be interpreted as a more preferred or more advantageous technical solution.

[0025] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked.

[0026] In this document, “upper”, “lower”, “front”, “back”, “left”, “right”, etc. are only used to indicate the relative position relationship between related parts, rather than to limit the absolute positions of these related parts.

[0027] In this article, "first", "second", etc. are only used to distinguish each other, and do not indicate the importance and order, or the premise of each other's existence.

[0028] In this article, "equal", "same" and the like are not strictly limited in the mathematical and / or geometric sense, but also include errors that can be understood by those skilled in the art and are allowed in manufacturing or use. Unless otherwise specified, the numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges contained therein.

[0029] The embodiments of the present application provide an explosion-proof sound column, in which the speaker unit and the hardware unit are designed to have independent explosion-proof cavities, so the shell of the speaker sound column does not need to have an explosion-proof structure. This split-cavity design that miniaturizes the explosion-proof structure can not only reduce the manufacturing requirements of the explosion-proof structure, but also improve the sound transmission effect through miniaturization.

[0030] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0031] like Figures 1 to 5 As shown, one embodiment of the present application provides an explosion-proof sound column, comprising: The housing 1 comprises a mesh panel 1a and a mounting plate 1b installed inside the mesh panel 1a; At least one explosion-proof speaker 100, which is installed on the mounting plate 1b; The explosion-proof hardware chamber 80 is installed in the housing 1 .

[0032] In this example, the explosion-proof speaker 100 includes a lower cover 10 and an upper cover 20 that are assembled together to form a cavity, and a speaker unit 30 installed in the cavity. The edge of the upper cover 20 has a first step that forms a first stop explosion-proof surface A with the lower cover 10, and the bottom surface 11 of the lower cover 10 has a cable hole 12 that passes through the bottom surface 11.

[0033] The explosion-proof hardware cavity 80 includes a hardware cavity lower cover 81 and a hardware cavity upper cover 82 which are connected to each other to form a hollow cavity, and a hardware cavity top cover 83 which covers the hardware cavity upper cover 82. The edge of the hardware cavity top cover 83 has a step portion which forms a fourth stop explosion-proof surface D with the hardware cavity upper cover 82. The hardware cavity top cover 83 has a hardware cavity cable hole 831 which passes through the hardware cavity top cover 83.

[0034] Furthermore, the speaker unit 30 of each explosion-proof speaker 100 is electrically connected to the circuit board in the hollow cavity via the cable 60, the first end of the cable 60 is installed in the cable hole 12 via the first stuffing box 13, and the second end is installed in the hardware cavity cable hole 831 via the second stuffing box 832, the first stuffing box 13 has a third step that forms a third stop explosion-proof surface C with the cable hole 12, and the second stuffing box 832 forms a fifth stop explosion-proof surface E with the hardware cavity cable hole 831.

[0035] In this example, the housing 1 may be configured as a housing of an ordinary electronic device that does not need to meet explosion-proof requirements, and may include a housing surface that does not need to provide sealing performance. For example, it includes a mesh panel 1a, a rear housing 1c docked with the mesh panel 1a, and an upper cover plate 1d and a lower cover plate 1e that close the upper and lower edges of the mesh panel 1a and the rear housing 1c. The fixed connection method may include but is not limited to fastener connection, snap connection, etc., and does not need to provide excessive sealing performance. The explosion-proof hardware cavity 80 is preferably supported on the lower cover plate 1e.

[0036] In the explosion-proof sound column of this example, each speaker unit is designed as an explosion-proof speaker 100, that is, each speaker unit has an explosion-proof shell and is designed as an explosion-proof module, which is more conducive to the expansion of the model and saves subsequent development time and cost. By selecting explosion-proof speakers of different models, explosion-proof sound columns with different performances can be formed. And hardware devices such as circuit boards are also independently arranged in the explosion-proof hardware cavity 80, and the explosion-proof hardware cavity also has an explosion-proof shell. Among them, each speaker unit is electrically connected to the circuit board in the explosion-proof hardware cavity 80 via a cable 60.

[0037] Specifically, the explosion-proof speaker 100 includes a lower cover 10 and an upper cover 20 that are assembled to form a cavity. The edge of the upper cover 20 has a first step that forms a first stop flameproof surface A with the lower cover 10. The joint between the lower cover 10 and the upper cover 20 forms an explosion-proof structure through the first stop flameproof surface A. The bottom surface 11 of the lower cover 10 has a cable hole 12 that penetrates the bottom surface 11. The first end of the cable 60 is installed in the cable hole 12 via a first stuffing box 13. The first stuffing box 13 has a third step that forms a third stop flameproof surface C with the cable hole 12. Then, the cable hole 12 connected to the cavity forms an explosion-proof structure through the third stop flameproof surface C.

[0038] The explosion-proof hardware cavity 80 includes a hardware cavity lower cover 81 and a hardware cavity upper cover 82 that are connected to each other to form a hollow cavity, and a hardware cavity top cover 83 that covers the hardware cavity upper cover 82. The edge of the hardware cavity top cover 83 has a step portion that forms a fourth stop flameproof surface D with the hardware cavity upper cover 82. The joint between the hardware cavity top cover 83 and the hardware cavity upper cover 82 forms an explosion-proof structure through the fourth stop flameproof surface D. The hardware cavity top cover 83 has a hardware cavity cable hole 831 that passes through the hardware cavity top cover 83. The second end of the cable 60 is installed in the hardware cavity cable hole 831 via a second stuffing box 832. The second stuffing box 832 and the hardware cavity cable hole 831 form a fifth stop flameproof surface E. The hardware cavity cable hole 831 connected to the hollow cavity forms an explosion-proof structure through the fifth stop flameproof surface E.

[0039] In this example, the airtightness of the explosion-proof speaker cavity ensures the sound transmission effect and explosion-proof performance of the speaker, the airtightness of the hollow cavity of the explosion-proof hardware cavity ensures the explosion-proof performance, and the internal connecting cables are designed as separate explosion-proof structural parts, which is convenient for production line assembly and maintenance. After the first stuffing box and the second stuffing box are disassembled, the internal components can be replaced. In this example, all connectors or plug-ins that are prone to sparks are isolated from the cavity of the explosion-proof speaker and the hollow cavity of the explosion-proof hardware cavity, which can provide higher explosion-proof performance. And because the volume of the speaker cavity with explosion-proof performance is reduced, the sound transmission effect of the speaker is far better than that of a speaker sound column whose overall shell is designed as an explosion-proof structure.

[0040] like Figure 3 and Figure 4 As shown, the explosion-proof sound column of this example includes an explosion-proof hardware cavity unit 80, and the explosion-proof hardware cavity unit 80 includes a hardware cavity lower cover 81 and a hardware cavity upper cover 82 that are connected to each other to form a hollow cavity for accommodating hardware. Among them, the hardware cavity lower cover 81 and the hardware cavity upper cover 82 can both be formed as a bottomed cylinder, and the bottom surfaces of the hardware cavity lower cover 81 and the hardware cavity upper cover 82 are arranged away from each other. Among them, the explosion-proof hardware cavity unit 80 defines an axial direction L perpendicular to the bottom surfaces of the hardware cavity lower cover 81 and the hardware cavity upper cover 82 and a radial direction R perpendicular to the axial direction L. The axial direction L is perpendicular to the mounting plate 1b.

[0041] In this example, the edges of the hardware cavity lower cover 81 and the hardware cavity upper cover 82 have flanges protruding outward along the radial direction R, and the flange of the hardware cavity lower cover 81 and the flange of the hardware cavity upper cover 82 are butted against each other and connected via fasteners. Preferably, the flange of the hardware cavity upper cover 82 has a first flange 821 protruding toward one side of the hardware cavity lower cover 81, and the flange of the hardware cavity lower cover 81 has a first groove 811 for accommodating the first flange 821, and the first flange 821 extends into the first groove 811 to form a bent sealing structure. Among them, the first flange 821 and the first groove 811 are located on the inner side of the fastener in the radial direction. Preferably, the first groove 811 is filled with a third filler 812 to fill the gap between the first flange 821 and the first groove 811. The third filler 812 can be formed by epoxy resin filling.

[0042] The circuit board and the power module can be arranged in the hollow cavity formed by the docking of the hardware cavity lower cover 81 and the hardware cavity upper cover 82. The cables connected to the power module and the circuit board can extend out of the hollow cavity through the hardware cavity cable hole 831. In a preferred example, it further includes a hardware cavity top cover 83, the bottom surface of the hardware cavity upper cover 82 has an opening, and the hardware cavity top cover 83 is used to cover the hardware cavity upper cover 82. Among them, the edge of the hardware cavity top cover 83 has a step portion that forms a fourth stop flameproof surface D with the hardware cavity upper cover 82, and the hardware cavity top cover 83 has a hardware cavity cable hole 831 that penetrates the hardware cavity top cover 83 along the axial direction L. The second end of the cable 60 for the speaker unit is installed in the hardware cavity cable hole 831 via the second stuffing box 832, and the second stuffing box 832 has a fourth filler that wraps the cable 60. The fourth filler can be formed by epoxy resin filling.

[0043] The second stuffing box 832 and the hardware cavity cable hole 831 form a fifth stop flameproof surface E extending along the axial direction L.

[0044] The hardware cavity cable hole 831 penetrates the hardware cavity top cover 83 along the axial direction L. It can be understood that the hardware cavity cable hole 831 may have a step portion with a shrinking diameter along the direction from the outside to the inside. The second stuffing box 832 has an outer diameter that matches the hardware cavity cable hole 831, so as to achieve the limit in the axial direction L through the step portion. The second stuffing box 832 is installed in the hardware cavity cable hole 831, and forms a stop flameproof surface that fits the hardware cavity cable hole 831 through its outer wall.

[0045] The second stuffing box 832 is fixed to the hardware cavity cable hole 831 via the second compression nut 833. The second compression nut 833, the second stuffing box 832, and the center of the hardware cavity cable hole 831 all have a center hole for the cable 60 to pass through. The second compression nut 833 fits the peripheral wall of the hardware cavity cable hole 831 to fix the second stuffing box 832 in the hardware cavity cable hole 831. In the axial direction L, the second stuffing box 832 is limited by the second compression nut 833 and the step portion.

[0046] In this example, the connecting cable of the speaker unit is placed outside on the top cover of the hardware cavity, making it more convenient to install and maintain.

[0047] Further, the explosion-proof hardware chamber 80 includes: An external cable hole 84, the external cable hole 84 passes through the lower cover 81 of the hardware cavity, and the external cable hole 84 has a hole wall 841 protruding from the lower cover 81 of the hardware cavity and passing through the housing 1; The external cable 61 is electrically connected to the circuit board in the hollow cavity via the external cable hole 84 . The external cable hole 84 contains a fifth filler that wraps the external cable 61 . The hole wall 841 is fixed to the shell 1 via a third clamping nut 842 .

[0048] There is no need to provide an explosion-proof or sealing structure between the hole wall 841 and the housing 1. The gap between the hole wall 841 and the external cable 61 is filled with the fifth filling material.

[0049] In one example, the hardware cavity upper cover 82 further has an inspection hole 19 that penetrates the hardware cavity upper cover 82, and the inspection hole 19 is closed from the outside by a plug 191. The inspection hole 19 is conducive to the performance inspection of the assembled product by the production line to prevent the outflow of defective products. When the sealing ring and other parts of the explosion-proof product are omitted from assembly, it is easy to cause the infiltration of gas and dust, resulting in the generation of electric sparks. After adding the airtight inspection hole, the integrity of the assembly can be ensured.

[0050] like Figure 5 As shown, the explosion-proof sound column of this example includes an explosion-proof speaker 100. The explosion-proof speaker in this example is formed by a lower cover and an upper cover that are butted against each other. The lower cover 10 is formed as a bottomed cylinder, including a bottom surface 11 and a side wall surrounding the edge of the bottom surface 11, wherein the shape of the bottom surface 11 is not limited, and can be formed into a circular or quadrilateral shape, for example. The edge of the upper cover 20 has a first step extending toward the lower cover 10 to form a first stop flameproof surface A with the side wall of the lower cover 10. The first step includes a first stop flameproof surface A and a flange portion perpendicular to the first stop flameproof surface A, and the flange portion protrudes outward from the first stop flameproof surface A to form a fixing surface for connecting with the lower cover 10. The lower cover 10 and the upper cover 20 are fixedly connected via fasteners to form a cavity with explosion-proof performance, and the speaker unit 30 is arranged in the cavity.

[0051] Among them, the upper cover of the explosion-proof speaker of this embodiment has a sound-emitting part 21 on one side, and the sound-emitting part 21 passes through the upper cover 20 to communicate with the cavity, and the sound waves generated by the speaker unit 30 are directly propagated outward from the sound-emitting part 21. In this example, since the explosion-proof cavity is composed of an upper cover and a lower cover that are adapted to the size of the speaker unit 30, the sound-emitting part 21 does not need to be reduced in size based on the limitations of structural strength and explosion-proof requirements, but can be set to a size that is adapted to the bell mouth of the speaker unit 30, such as a circle with the same shape and size as the bell mouth. The sound-emitting part 21 is integrally covered by a first metal sintered block 40, which is used for explosion isolation, wherein the first metal sintered block 40 is located on one side of the cavity. The first metal sintered block 40 can be formed, for example, of SUS304 stainless steel. Preferably, the first metal sintered block 40 has air permeability due to the density of the structure. Optionally, the first metal sintered block 40 has a sound-permeable property to ensure the sound transmission effect of the explosion-proof speaker.

[0052] The metal sintered block is usually fixed by fasteners, but this fixing method cannot guarantee compliance with explosion-proof performance requirements. In this embodiment, the cavity has a first mounting groove 22 surrounding the sound-emitting portion 21, and the edge of the first metal sintered block 40 is fixedly installed in the first mounting groove 22 via a first filler 23, and the first filler 23 fills the gap between the first metal sintered block 40 and the first mounting groove 22.

[0053] The first filler 23 has elastic deformability, and its size is larger than the gap between the first metal sintered block 40 and the first mounting groove 22. When the first metal sintered block 40 is fixed in the first mounting groove 22, the first filler 23 is squeezed by the first metal sintered block 40 so that the gap between the first metal sintered block 40 and the first mounting groove 22 is completely filled with the first filler 23, and the sound-emitting part 21 can be completely sealed by the first metal sintered block 40, thereby meeting the explosion-proof requirements. Through the setting of this sealing structure, the size of the sound-emitting part 21 is not limited by the requirements of explosion-proof performance. Therefore, the sound-emitting part 21 of this example can be set as an integrated structure that matches the bell mouth of the speaker unit 30. This size can provide the sound transmission area to the greatest extent, reduce the obstruction to sound propagation, and achieve the ideal effect of transmitting sound.

[0054] The first filler 23 may be an epoxy resin filler, which may be formed to have a U-shaped cross section to wrap the edge of the first metal sintered block 40 to achieve a sealed closure of the sound-emitting portion 21 .

[0055] The cavity of the explosion-proof speaker defines an axial direction L perpendicular to the bottom surface 11 and a radial direction R perpendicular to the axial direction L. The first filler 23 wraps the edge of the metal sintered block 40 from the outside to fill the gap between the metal sintered block 40 and the first mounting groove 22 in the axial direction L and the radial direction R.

[0056] The edges of the lower cover 10 and the upper cover 20 have flanges protruding outward along the radial direction R, and the flanges of the lower cover 10 and the upper cover 20 are butted against each other and connected via fasteners. A lower sealing ring located inside the fasteners is provided between the lower cover 10 and the upper cover 20 to achieve sealing at the joint between the lower cover 10 and the upper cover 20.

[0057] The first stop flameproof surface A extends from the inner edge of the upper cover 20 along the axial direction L and fits the inner surface of the side wall of the lower cover 10. The length of the first stop flameproof surface A extending along the axial direction L depends on the explosion-proof performance requirements. The increase in the length of the first stop flameproof surface A corresponds to the improvement of the explosion-proof performance. That is, the length of the first stop flameproof surface A is positively correlated with the explosion-proof level.

[0058] like Figure 5 As shown, the bottom surface 11 has a cable hole 12 penetrating the bottom surface 11 .

[0059] The first end of the cable 60 is installed in the cable hole 12 via the first stuffing box 13, and the cable 60 is connected to the speaker unit 30 via the cable hole 12. The first stuffing box 13 contains a second stuffing material 131 that wraps the cable 60. The first stuffing box 13 has a third step which forms a third stop flameproof surface with the cable hole 12 , and the third stop flameproof surface extends along the axial direction L.

[0060] The cable hole 12 penetrates the bottom surface 11 along the axial direction L. It can be understood that the cable hole 12 may have a step portion with a shrinking diameter along the direction from the outside to the inside. The first stuffing box 13 has an outer diameter that matches the cable hole 12, so as to achieve the limit in the axial direction L through the step portion. The first stuffing box 13 is installed in the cable hole 12, and forms a third stop flameproof surface C that fits the cable hole 12 through its outer wall. The cable 60 for the speaker unit 30 is inserted into the cable hole 12 through the first stuffing box 13, and the gap between the cable 60 and the first stuffing box 13 is filled with the second filler 131. The second filler 131 can be formed by epoxy resin filling.

[0061] The first stuffing box 13 is fixed to the cable hole 12 via the first compression nut 14. The first compression nut 14, the first stuffing box 13, and the center of the cable hole 12 all have a center hole for the cable 60 to pass through. The first compression nut 14 is threadedly connected to the peripheral wall of the cable hole 12 to fix the first stuffing box 13 in the cable hole 12. In the axial direction L, the first stuffing box 13 is limited by the first compression nut 14 and the step portion.

[0062] The explosion-proof loudspeaker in this embodiment can be arranged as a single unit, or can be designed as a sound column with different powers by combining and arranging multiple groups of units. It has strong scalability, can reduce design and development time, reduce development costs, etc.

[0063] Among them, the explosion-proof speaker in this application can be implemented as Figure 5 The woofer shown in the figure. Corresponding to the sound-generating principle of the woofer, the cavity is divided into two parts, the front cavity and the rear cavity, by the speaker unit 30.

[0064] Specifically, the upper cover 20 has an annular side wall extending along the axial direction L, and the annular side wall extends from the inner surface of the upper cover 20 away from the bottom surface 11; Further including: A top cover 50, the top cover 50 closes the end of the annular side wall facing away from the bottom surface 11; The sound-emitting portion 21 passes through the top cover 50 , the first mounting groove 22 is located on the inner surface of the top cover 50 , and the cavity is divided by the speaker unit 30 into a rear cavity formed by the lower cover 10 and a front cavity formed by the annular side wall and the top cover 50 .

[0065] In this example, the upper cover 20 further extends toward the side away from the bottom surface 11 to form an annular side wall, and the front end of the annular side wall (the end farthest from the bottom surface 11) is closed by the top cover 50. The speaker unit 30 is fixed to the inner surface of the upper cover 20, and the annular side wall protruding forward of the upper cover 20, the top cover 50, and the diaphragm of the speaker unit 30 enclose a front cavity to form the front sound-emitting part of the speaker. The lower cover 10 and the rear surface of the diaphragm enclose a rear cavity for the speaker unit.

[0066] In this example, the sound-emitting portion 21 is disposed on the top cover 50 and penetrates the top cover 50, and the sound-emitting portion 21 is covered by the first metal sintered block 40 installed on the top cover 50. The first mounting groove 22 for accommodating the first metal sintered block 40 is located on the inner surface of the top cover 50, and the first mounting groove 22 also has a first filler 23 for filling the gap. The area of ​​the first metal sintered block 40 is larger than that of the sound-emitting portion 21, so as to have an edge accommodated in the first mounting groove 22.

[0067] In existing explosion-proof speakers, the front cavity sound-emitting part of the speaker is usually designed to be relatively small. The smaller its size, the worse the acoustic effect and the worse the loudness of the mid-high frequency. In this example, the edge of the top cover 50 has a second step that forms a second stop flameproof surface B with the annular side wall, and the second stop flameproof surface extends along the axial direction L. The second stop flameproof surface B can be realized by threaded connection, thereby reducing the size occupied by the stop flameproof surface.

[0068] Specifically, it includes: The first pressing plate 41 fixes the first metal sintered block 40 in the first mounting groove 22 , and the first pressing plate 41 abuts against the inner surface of the first metal sintered block 40 .

[0069] The first metal sintered block 40 is fixed to the first mounting groove 22, and the first pressing plate 41 fixes the first metal sintered block 40 from one side of the cavity to abut against the inner surface of the first metal sintered block 40 and compress the first filler 23. A silicone pad may be used between the first pressing plate 41 and the first metal sintered block 40. The first pressing plate 41 is fixed to the inner surface of the top cover 50 via fasteners. The contact surface between the top cover 50 and the upper cover 20 may have a front sealing ring to improve the sealing performance and explosion-proof performance.

[0070] The first pressing plate 41 is formed in a ring shape. Optionally, the silicone pad is also formed in a ring shape. Then the first pressing plate 41 can expose the sound-generating part of the speaker unit 30 to avoid affecting the sound transmission effect.

[0071] In one example, based on the sound-generating principle of the speaker unit 30, the diaphragm of the speaker unit 30 will cause a change in the volume of the rear cavity when vibrating. In order to achieve a better low-frequency effect and maintain the stability of the sound quality, the bottom surface 11 has an air vent 15 that runs through the bottom surface 11, and the second metal sintered block 16 covers the air vent 15 from the inside.

[0072] Similar to the fixing method of the first metal sintered block, the cavity has a second mounting groove surrounding the vent hole 15, and the edge of the second metal sintered block 16 is fixedly installed in the second mounting groove via a second filler 17, and the second filler 17 fills the gap between the second metal sintered block 16 and the second mounting groove.

[0073] Similarly, include: The second pressing plate 18 fixes the second metal sintered block 16 in the second mounting groove, and the second pressing plate 18 abuts against the inner surface of the second metal sintered block 16. A silicone pad may be used between the second pressing plate 18 and the second metal sintered block 16. The second pressing plate 18 is fixed to the inner surface of the bottom surface 11 via a fastener.

[0074] The second pressing plate 18 is formed in a ring shape. Optionally, the silicone pad is also formed in a ring shape. Then the second pressing plate 18 can expose the portion corresponding to the air leakage hole 15 to avoid affecting the ventilation effect.

[0075] Among them, it also includes: The waterproof and breathable membrane 161 is isolated between the air leakage hole 15 and the second metal sintered block 16 .

[0076] The waterproof breathable membrane 161 has the function of preventing water molecules from entering the cavity and allowing gas molecules to freely enter and exit the cavity. The diaphragm of the speaker unit 30 will cause the volume of the rear cavity to change when vibrating, so the air leakage hole 15 needs to allow gas to enter and exit. Furthermore, during operation, the speaker unit 30 will generate heat, and water mist will be generated due to the temperature difference between the inside and outside, thereby affecting the waterproofness of the internal components. Adding the air leakage hole 15 is conducive to ventilation and heat dissipation, and maintains the acoustic performance of the speaker for a long time. Furthermore, a certain amount of desiccant is usually placed in the rear cavity.

[0077] Normally, when a vent hole is opened in the rear cavity, an explosion-proof structure needs to be added to the hole, which will undoubtedly increase the overall volume and design and manufacturing cost of the explosion-proof speaker. However, the metal sintered block in this example uses fillers to seal the hole, and there is no need to increase the axial length of the stopper explosion-proof surface to achieve sealing and explosion-proofing, which can not only reduce the overall volume of the speaker, but also ensure the sound transmission effect and explosion-proof performance.

[0078] Furthermore, the bottom surface 11 has an inspection hole 19 that penetrates the bottom surface 11, and the inspection hole 19 is closed from the outside by a plug 191. The inspection hole 19 is conducive to the performance inspection of the assembled product on the production line to prevent the outflow of defective products. When the sealing ring and other parts of the explosion-proof product are omitted from assembly, it is easy to cause the infiltration of gas and dust, resulting in the generation of electric sparks. After adding the airtight inspection hole, the integrity of the assembly can be ensured.

[0079] like Figure 6 As shown, the explosion-proof speaker 100 in the present application can be implemented as a tweeter, and the speaker unit 30 is formed as a horn tube, and the horn mouth of the horn tube is fixed to the inner surface of the upper cover 20. The sound-emitting part 21 is opened on the upper cover 20, and the first mounting groove 22 is located on the inner surface of the upper cover 20. In this example, the speaker unit 30 is formed as a tweeter.

[0080] The explosion-proof speaker of this embodiment has a sound-emitting part 21 on one side of the upper cover, which passes through the upper cover 20 to communicate with the cavity, and the sound waves generated by the speaker unit 30 are directly propagated outward from the sound-emitting part 21. In this example, since the explosion-proof cavity is composed of an upper cover and a lower cover that are adapted to the size of the speaker unit 30, the sound-emitting part 21 does not need to be reduced in size based on the limitations of structural strength and explosion-proof requirements, but can be set to an integrated structure adapted to the bell mouth of the speaker unit 30, such as a circle with the same shape and size as the bell mouth. The sound-emitting part 21 is integrally covered by a first metal sintered block 40, wherein the first metal sintered block 40 is located on one side of the cavity. The first metal sintered block 40 can be formed, for example, of SUS304 stainless steel.

[0081] Unlike woofers, tweeters are usually smaller in size because they do not need to move a large amount of air to produce sound. The diaphragm of a tweeter is usually lighter and harder to quickly respond to high-frequency sound waves. Therefore, the front cavity of the tweeter does not need to be large in size. In this example, the horn of the speaker unit 30 is directly mounted on the inner surface of the upper cover 20, and the upper cover 20 forms a flat surface that is flush with the front end of the lower cover 10.

[0082] The bell mouth of the horn tube fixes the first metal sintered block 40 in the first mounting groove 22 , and the bell mouth of the horn tube abuts against the inner surface of the first metal sintered block 40 .

[0083] The metal sintered block is usually fixed by fasteners, but this fixing method cannot guarantee compliance with explosion-proof performance requirements. In this embodiment, the cavity has a first mounting groove 22 surrounding the sound-emitting portion 21, and the edge of the first metal sintered block 40 is fixedly installed in the first mounting groove 22 via a first filler 23, and the first filler 23 fills the gap between the first metal sintered block 40 and the first mounting groove 22.

[0084] The first filler 23 has elastic deformability, and its size is larger than the gap between the first metal sintered block 40 and the first mounting groove 22. When the first metal sintered block 40 is fixed in the first mounting groove 22, the first filler 23 is squeezed by the first metal sintered block 40 so that the gap between the first metal sintered block 40 and the first mounting groove 22 is completely filled with the first filler 23, and the sound-emitting part 21 can be completely sealed by the first metal sintered block 40, thereby meeting the explosion-proof requirements. Through the setting of this sealing structure, the size of the sound-emitting part 21 is not limited to the requirements of explosion-proof performance. Therefore, the sound-emitting part 21 of this example can be set to a size that matches the bell mouth of the speaker unit 30. This size can provide the sound transmission area to the greatest extent, reduce the obstruction to sound propagation, and achieve the ideal effect of transmitting sound.

[0085] Similar to the woofer, Figure 6 The explosion-proof speaker 100 shown may also have an air vent 15 and an inspection hole 19, and the description of their structure and effect can be referred to Figure 5 Related instructions.

[0086] like Figure 7 As shown, the explosion-proof loudspeaker 100 in the present application can be implemented as a tweeter, and the explosion-proof housing of the explosion-proof loudspeaker 100 can be formed in the form of a horn.

[0087] Specifically, the upper cover 20 has a first annular side wall 201 and a second annular side wall 202 extending along the axial direction L, the first annular side wall 201 surrounds the second annular side wall 202 from the outside, and the front edge of the first annular side wall 201 is further away from the bottom surface 11 than the front edge of the second annular side wall 202; The front edge of the first annular side wall 202 is fixed to the mounting plate 1b; The front edge of the second annular sidewall 202 has a sound generating portion 21 communicating with the cavity. The first metal sintered block 40 covers the sound generating portion 21 from the inside. The sixth filler fills the gap between the outer edge of the first metal sintered block 40 and the second annular sidewall 202 .

[0088] The first annular side wall 201 is formed in a bell-shaped shape with a gradually increasing diameter to form the outer wall of the horn, and the second annular side wall 202 is formed in a bell-shaped shape with a gradually decreasing diameter to form a sound-emitting portion at a focal position in the first annular side wall 201 .

[0089] In this example, since the structure of the sound-emitting portion 21 is relatively small, the first metal sintered block 40 is fixed to the inner wall of the first annular side wall 201 via the fourth clamping nut 203. The gap between the outer edge of the first metal sintered block 40 and the second annular side wall 202 is filled with the sixth filler, and the fourth clamping nut 203 is threadedly connected to the inner wall of the first annular side wall 201. In the axial direction L, the sealing at the sound-emitting portion 21 is provided by the sixth filler at the outer edge of the first metal sintered block 40.

[0090] It can be seen from the above technical solutions that in this example, the airtightness of the explosion-proof speaker cavity ensures the sound transmission effect and explosion-proof performance of the speaker, the airtightness of the hollow cavity of the explosion-proof hardware cavity ensures the explosion-proof performance, and the internal connecting cables are designed as separate explosion-proof structural parts, which is convenient for production line assembly and maintenance. After the first stuffing box and the second stuffing box are disassembled, the internal components can be replaced. In this example, all connectors or plug-ins that are prone to sparks are isolated from the cavity of the explosion-proof speaker and the hollow cavity of the explosion-proof hardware cavity, which can provide higher explosion-proof performance. And because the volume of the speaker cavity with explosion-proof performance is reduced, the sound transmission effect of the speaker is far better than that of a speaker sound column whose overall shell is designed as an explosion-proof structure.

[0091] In the single speaker unit, the size of the sound-emitting part can be maximized through the sealing setting of the explosion-proof structure of the metal sintered block, which can provide the maximum sound transmission area and reduce the obstruction to sound propagation to achieve the ideal sound transmission effect.

[0092] In one example, in a single speaker unit, based on the sound-generating principle of the speaker unit, the diaphragm of the speaker unit will cause the volume of the back cavity to change when vibrating. In order to achieve better low-frequency effects and maintain the stability of the sound quality, the bottom surface has an air vent that runs through the bottom surface. And through the fixing and sealing method of the metal sintered block in this example, there is no need to design a stopper explosion-proof surface that increases the length in the axial direction. On the premise of reducing the overall volume of the speaker, the sound transmission effect and explosion-proof performance are guaranteed. Furthermore, by setting up inspection holes, it is beneficial for the production line to inspect the performance of the assembled products and prevent the outflow of defective products. When parts such as sealing rings are omitted from the assembly of explosion-proof products, it is easy to cause the infiltration of gas and dust, resulting in the generation of electric sparks. After adding an airtight inspection hole, the integrity of the assembly can be ensured.

[0093] In this example, the connecting cable of the speaker unit is placed outside on the top cover of the hardware cavity, making it more convenient to install and maintain.

[0094] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. An explosion-proof sound column, characterized in that: include: A shell (1), the shell (1) comprising a mesh panel (1a) and a mounting plate (1b) mounted on the inner side of the mesh panel (1a); At least one explosion-proof loudspeaker (100), the explosion-proof loudspeaker (100) being mounted on the mounting plate (1b), the explosion-proof loudspeaker (100) comprising a lower cover (10) and an upper cover (20) which are assembled to form a cavity, and a speaker unit (30) mounted in the cavity, the edge of the upper cover (20) having a first step which forms a first stop flameproof surface with the lower cover (10), and the bottom surface (11) of the lower cover (10) having a cable hole (12) which passes through the bottom surface (11); An explosion-proof hardware cavity (80), the explosion-proof hardware cavity (80) being installed in the housing (1), the explosion-proof hardware cavity (80) comprising a hardware cavity lower cover (81) and a hardware cavity upper cover (82) which are butted against each other to form a hollow cavity, and a hardware cavity top cover (83) which covers the hardware cavity upper cover (82), the edge of the hardware cavity top cover (83) comprising a step portion which forms a fourth stop flameproof surface with the hardware cavity upper cover (82), and the hardware cavity top cover (83) comprising a hardware cavity cable hole (831) which passes through the hardware cavity top cover (83); The speaker unit (30) of each explosion-proof loudspeaker (100) is electrically connected to the circuit board in the hollow cavity via a cable (60); a first end of the cable (60) is installed in the cable hole (12) via a first stuffing box (13); a second end of the cable (60) is installed in the hardware cavity cable hole (831) via a second stuffing box (832); the first stuffing box (13) has a third step that forms a third stop flameproof surface with the cable hole (12); and the second stuffing box (832) forms a fifth stop flameproof surface with the hardware cavity cable hole (831).

2. The explosion-proof sound column according to claim 1, characterized in that: The cavity defines an axial direction (L) perpendicular to the bottom surface (11) and a radial direction (R) perpendicular to the axial direction (L), wherein the axial direction (L) is perpendicular to the mounting plate (1b); The first stop flameproof surface, the third stop flameproof surface, the fourth stop flameproof surface, and the fifth stop flameproof surface all extend along the axial direction (L).

3. The explosion-proof sound column according to claim 2, characterized in that: The first stuffing box (13) contains a second stuffing material (131) for wrapping the cable (60), and the first stuffing box (13) is fixed to the cable hole (12) via a first compression nut (14); The second stuffing box (832) contains a fourth stuffing material that wraps the cable (60), and the second stuffing box (832) is fixed to the cable hole (831) of the hardware cavity via a second compression nut (833).

4. The explosion-proof sound column according to claim 2, characterized in that: The edge of the hardware cavity upper cover (82) has a first flange (821) protruding toward the hardware cavity lower cover (81), and the edge of the hardware cavity lower cover (81) has a first groove (811) for accommodating the first flange (821), and the first groove (811) is filled with a third filling material (812) to fill the gap between the first flange (821) and the first groove (811).

5. The explosion-proof sound column according to claim 2, characterized in that: The upper cover (20) has an annular side wall extending along the axial direction (L), and the annular side wall extends from the inner surface of the upper cover (20) away from the bottom surface (11); The explosion-proof loudspeaker (100) comprises: A top cover (50), the top cover (50) closing a port of the annular side wall facing away from the bottom surface (11); The top cover (50) has a sound-generating portion (21) penetrating the top cover (50) along the axial direction (L); the first metal sintered block (40) covers the sound-generating portion (21) from the inside; the inner surface of the top cover (50) has a first mounting groove (22) surrounding the sound-generating portion (21); the edge of the first metal sintered block (40) is fixedly mounted in the first mounting groove (22) via a first filler (23); and the first filler (23) fills a gap between the first metal sintered block (40) and the first mounting groove (22); The cavity is divided by the speaker unit (30) into a rear cavity formed by the lower cover (10) and a front cavity formed by the annular side wall and the top cover (50); The edge of the top cover (50) has a second step which forms a second stop flameproof surface with the annular side wall, and the second stop flameproof surface extends along the axial direction (L).

6. The explosion-proof sound column according to claim 2, characterized in that: The cavity has a sound-generating portion (21) penetrating the upper cover (20); the inner surface of the upper cover (20) has a first mounting groove (22) surrounding the sound-generating portion (21); a first metal sintered block (40) covers the sound-generating portion (21) from the inside; an edge of the first metal sintered block (40) is fixedly mounted in the first mounting groove (22) via a first filler (23); the first filler (23) fills a gap between the first metal sintered block (40) and the first mounting groove (22); The speaker unit (30) is formed as a horn tube, the horn mouth of the horn tube fixes the first metal sintered block (40) in the first installation groove (22), and the horn mouth of the horn tube abuts against the inner surface of the first metal sintered block (40).

7. The explosion-proof sound column according to claim 2, characterized in that: The upper cover (20) comprises a first annular side wall (201) and a second annular side wall (202) extending in an axial direction (L); the first annular side wall (201) surrounds the second annular side wall (202) from the outside, and a front edge of the first annular side wall (201) is further away from the bottom surface (11) than a front edge of the second annular side wall (202); The front edge of the first annular side wall (202) is fixed to the mounting plate (1b); The front edge of the second annular side wall (202) has a sound-generating portion (21) connected to the cavity, the first metal sintered block (40) covers the sound-generating portion (21) from the inside, and the sixth filler fills the gap between the outer edge of the first metal sintered block (40) and the second annular side wall (202).

8. The explosion-proof sound column according to claim 5 or 6, characterized in that: The bottom surface (11) has an air leakage hole (15) penetrating the bottom surface (11); the second metal sintered block (16) covers the air leakage hole (15) from the inside; and a waterproof breathable membrane (161) is isolated between the air leakage hole (15) and the second metal sintered block (16); The cavity has a second mounting groove surrounding the air leakage hole (15); the edge of the second metal sintered block (16) is fixedly mounted in the second mounting groove via a second filler (17); the second filler (17) fills a gap between the second metal sintered block (16) and the second mounting groove.

9. The explosion-proof sound column according to claim 5 or 6, characterized in that: The bottom surface (11) has an inspection hole (19) penetrating the bottom surface (11), and the inspection hole (19) is closed from the outside by a plug (191).

10. The explosion-proof sound column according to claim 1, characterized in that: The explosion-proof hardware chamber (80) comprises: An external cable hole (84), the external cable hole (84) passing through the lower cover (81) of the hardware cavity, the external cable hole (84) having a hole wall (841) protruding from the lower cover (81) of the hardware cavity and passing through the housing (1); The external cable (61) is electrically connected to the circuit board in the hollow cavity via the external cable hole (84); the external cable hole (84) contains a fifth filler that wraps the external cable (61); and the hole wall (841) is fixed to the shell (1) via a third clamping nut (842).

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