Sound production device for display device

Abstract

The present disclosure provides a sound production device for a display device. The display device (100) comprises a rear housing (1) and a modular middle frame assembly (2), and the rear housing has an inner side surface facing the modular middle frame assembly. The sound production device (10) comprises the rear housing and at least one exciter (3) mounted to the inner side surface of the rear housing.

Description

Sound emitting device for display device TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to the technical field of sound emitting, and in particular, to a sound emitting device for a display device such as a liquid crystal display. BACKGROUND

[0002] In the current sound emitting device for a display device such as a liquid crystal display, one solution is to lock an exciter on a back plate, and the vibration of the exciter drives the back plate to vibrate to emit sound. Because the back plate is packaged together with the liquid crystal module, the vibration of the back plate will drive the liquid crystal module to vibrate, and thus the screen of the whole machine will have a certain degree of jitter. To avoid this problem, it is possible to choose to add a corrugated buffer plastic between the back plate and the liquid crystal module to absorb the impact of the vibration of the back plate. However, this will undoubtedly cause the cost of the whole machine to increase, and also make the assembly of the whole machine complex. At the same time, the back plate serves as a load-bearing frame of the whole machine, and it almost contacts all the components of the display device, and the vibration of the back plate will also make the components it contacts vibrate together, which will make the whole display device have a greater risk of vibration sound.

[0003] SUMMARY

[0004] The purpose of the present disclosure is to provide a sound emitting device for a display device such as a liquid crystal display, which can reduce the risk of vibration sound of the whole display device, avoid the influence of vibration on the display module, and ensure the reliability of the whole display device.

[0005] To this end, the present disclosure provides a sound emitting device for a display device, the display device comprising a rear housing having an inner side facing a module middle frame assembly, and a module middle frame assembly, wherein the sound emitting device comprises the rear housing and at least one exciter mounted to the inner side of the rear housing.

[0006] In one solution of the present disclosure, the rear housing comprises a left side portion and an opposite right side portion, and one exciter is mounted to each of the left side portion and the right side portion. The above solution provides a left-right dual-channel sound emitting device, the exciter generates vibration by applying current such as alternating current, and the rear housing serves as a vibration sound emitting plate, which can reduce the risk of vibration sound of the whole machine, avoid the influence of vibration on the display module such as a liquid crystal display module (LCM), and ensure the reliability of the whole machine. However, it should be understood that the number and position of the exciters are not limited to this, and other numbers of exciters such as three or four can also be provided. In addition, the exciters can also be arranged on the upper and lower sides of the rear housing. These are all covered within the scope of the present application.

[0007] According to one preferred scheme of the present disclosure, the module middle frame assembly comprises a back plate, a middle frame and a display module, a vibration absorbing pad is arranged between the mating surface of the rear shell and the middle frame, and the gap between the exciter and the back plate is not less than 1.5 mm. The vibration absorbing pad can be made of ethylene-vinyl acetate copolymer (EVA) for example. In this scheme, since the vibration absorbing pad can absorb vibration, only a small amount of vibration is transmitted from the rear shell to the middle frame when the rear shell vibrates, and the vibration transmitted from the middle frame to other components is even smaller, which has less impact on other components, especially the liquid crystal display module part, and the whole machine has higher reliability.

[0008] In one preferred scheme of the present disclosure, the exciter comprises: an upper cover body; a lower cover body, the left and right sides of the lower cover body each have an installation lug, each installation lug has an installation hole; a first shock absorbing washer located between the upper cover body and the lower cover body; a first flexible plug located in the corresponding installation hole, the first flexible plug has a through hole; and a second shock absorbing washer and a buffer pad fixedly connected to the lower side of the lower cover body. It should be understood that the shape of the first shock absorbing washer depends on the shape of the upper cover body and the lower cover body, especially the shape of the mating surface, and the shape of the second shock absorbing washer depends on the shape of the mating surface of the rear shell and the rear shell, which can be circular, oval or rectangular for example. After the exciter is supplied with alternating current, the north-south poles of the magnetic field change alternately, and the vibrating component rises and falls under the action of attractive force and repulsive force. Moreover, the exciter has a small size.

[0009] In one scheme of the present disclosure, the inner side surface of the left side part and the inner side surface of the right side part are each provided with two screw posts with threaded blind holes, wherein the exciter is connected to the rear shell through the cooperation of the flexible plugs, the corresponding screw posts and threaded fasteners. Specifically, the exciter is connected to the rear shell by sleeving the two flexible plugs on the corresponding screw posts and by screwing the threaded fasteners into the threaded blind holes of each screw post and abutting against the corresponding flexible plugs. After the exciter is powered on, it will make up-and-down reciprocating motion, and after the exciter is powered on, it will make up-and-down reciprocating vibration, and the vibration of the exciter will be transmitted to the rear shell through the buffer pad at the bottom of the exciter. Since the exciter has a small size and the rear shell has a large size, after the vibration of the exciter is transmitted to the rear shell, it will cause point vibration of the rear shell, and further generate sound. The use of flexible plugs, screw posts and threaded fasteners for connection can avoid the opening of the rear shell, thereby ensuring the integrity of the whole machine shell.

[0010] According to one scheme of the present disclosure, the rear shell has four corner parts, and one exciter is installed at the inner side surface of each corner part. For example, the projection of the rear shell in the horizontal plane can be rectangular. This scheme provides a four-channel sound generating device, so that the display device does not need to provide an additional independent sound box.

[0011] In one preferred embodiment of the present disclosure, the rear housing has a mounting seat integrally formed at each of the corner portions, and the exciter is connected to the mounting seat through a connecting mechanism, wherein the connecting mechanism comprises: a vibrating plate comprising a first screw post and a second screw post having a threaded blind hole; a first threaded fastener cooperating with the threaded blind hole of the first screw post to connect the exciter to the vibrating plate; a second threaded fastener cooperating with the threaded blind hole of the second screw post to connect the vibrating plate to the mounting seat; and a second flexible plug sleeved on each second screw post, the flexible plug having a through hole.

[0012] According to one preferred embodiment of the present disclosure, a shock-absorbing pad is arranged between the rear housing and the vibrating plate, the vibrating plate is configured as a rectangular plate and has four second screw posts respectively located at four corners of the vibrating plate, and two first screw posts are arranged at intervals along the length direction of the vibrating plate; and the mounting seat comprises a rectangular supporting portion protruding inwardly from the inner side of the rear housing, the rectangular supporting portion has a central opening and fitting holes located at four corners of the rectangular supporting portion, the flexible plug and the second screw post are mounted to the mounting seat through the fitting holes.

[0013] In one embodiment of the present disclosure, the fitting hole has a first circular hole portion and a second circular hole portion in communication with the first circular hole portion; the flexible plug is a hollow component and has a cylindrical section and annular flange portions located at both ends of the cylindrical section, wherein the outer diameter of the annular flange portion is smaller than the diameter of the first circular hole portion, the outer diameter of the cylindrical section is smaller than or equal to the diameter of the second circular hole portion, and the diameter of the first circular hole portion is greater than the diameter of the second circular hole portion.

[0014] In the present disclosure, the first flexible plug and the second flexible plug are structurally identical and are preferably made of silica gel, however, other suitable materials are also feasible and are also covered within the scope of the present application.

[0015] According to one preferred embodiment of the present disclosure, the rectangular supporting portion has a first reinforcing rib and a second reinforcing rib extending towards the outer side of the rear housing to ensure the strength of the mounting seat.

[0016] According to one preferred embodiment of the present disclosure, the vibrating plate has a four-pyramid structure on the upper surface thereof facing the exciter. The vibrating plate is preferably made of polystyrene material. It should be understood that other suitable materials can also be selected for the vibrating plate.

[0017] The present disclosure also provides a display device comprising the sound generating device described above.

[0018] In one scheme of the present disclosure, the display device comprises a four-channel sound producing device, wherein the display device further comprises a display screen, a camera module, and a cover plate for mounting the camera module to the display screen, the camera module comprising: a first camera module located at the top side of the display screen, for vertical orientation of the display screen; a second camera module located at the right side of the display screen, for horizontal orientation of the right half of the display screen; and a third camera module located at the left side of the display screen, for horizontal orientation of the left half of the display screen.

[0019] According to one scheme of the present disclosure, the display device further comprises a control system configured to: when detecting that there is a sound signal output, the camera module starts to scan the display screen for the first time and divides the display area of the display screen evenly into three rows and three columns, i.e. nine areas; and compares the sound with the category and action of the things in each area one by one to confirm the relationship, so as to confirm in which area the sound occurs, and control the corresponding exciter to produce sound.

[0020] The sound producing device and the display device of the present disclosure have the following beneficial technical effects: the risk of whole machine vibration is smaller, the exciter is directly mounted to the rear shell, the vibration of the rear shell is transmitted to the middle frame, only the shock absorption between the rear shell and the middle frame needs to be done, and the whole machine vibration can be controlled; the structure is simpler, the assembly is more convenient, and the cost is lower; the whole machine reliability is higher; the exciter is directly mounted to the rear shell or mounted to the rear shell through the vibration plate, only a little vibration is transmitted to the middle frame when the rear shell or the vibration plate vibrates, the vibration transmitted to other components from the middle frame is less, the influence on other components, especially the liquid crystal module part, is smaller, and the whole machine reliability is higher; and good acoustic performance. BRIEF DESCRIPTION OF DRAWINGS

[0021] Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0022] FIG. 1 is a perspective view of a display device according to one embodiment of the present disclosure;

[0023] FIG. 2 is an exploded view of the display device shown in FIG. 1;

[0024] FIG. 3 is a perspective view of a sound producing device according to one embodiment of the present disclosure, wherein two exciters are mounted to the inner side surface of the rear shell;

[0025] FIG. 4 is an exploded view of a module middle frame assembly according to one embodiment of the present disclosure;

[0026] FIG. 5 is a rear view of the display device shown in FIG. 1;

[0027] FIG. 6 is an A-A sectional view of the display device shown in FIG. 5;

[0028] Figure 7 is an enlarged view of section B in Figure 6, showing details of the mounting of the exciter to the rear housing;

[0029] Figure 8 is a perspective view of an exciter according to one embodiment of the present disclosure;

[0030] Figure 9 is an exploded view of the exciter shown in Figure 8;

[0031] Figure 10 is an exploded view of the sound production device shown in Figure 3;

[0032] Figure 10A is a plot of the overall test acoustic THD for a display device employing a two-channel sound production device according to the present disclosure;

[0033] Figure 10B is a plot of the overall test acoustic RMS for a display device employing a two-channel sound production device according to the present disclosure;

[0034] Figure 11 is a perspective view of a display device according to another embodiment of the present disclosure, the inner side of the rear housing of which is provided with four exciters;

[0035] Figure 12 is a plan view of the rear housing of the display device shown in Figure 11, showing mounting seats for the exciters;

[0036] Figure 13 is an enlarged view of section C in Figure 12, showing details of the mounting seats;

[0037] Figure 14 is an exploded view of an exciter assembly according to one embodiment of the present disclosure;

[0038] Figure 14A is a cross-sectional view of an exciter assembly according to one embodiment of the present disclosure;

[0039] Figure 15 is a D-D cross-sectional view in Figure 12;

[0040] Figure 16 is an enlarged view of section E in Figure 15;

[0041] Figure 17 is a perspective view of the mounting seat in Figure 12;

[0042] Figure 18 is an exploded view of a four-channel sound production device shown in Figure 11;

[0043] Figure 19A is a front view of a flexible plug according to one embodiment of the present disclosure;

[0044] Figure 19B is a F-F cross-sectional view of the flexible plug shown in Figure 19A;

[0045] Figure 20 is a perspective view of a vibrating plate according to one embodiment of the present disclosure;

[0046] Figure 20A is an enlarged view of section G in Figure 20;

[0047] Figure 21 is a partially exploded view of one embodiment of a display device according to the present disclosure, the display device provided with a camera module; and

[0048] Figure 22 is a front view of a display device according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0049] The exemplary embodiments of the present disclosure are described in detail below. The exemplary embodiments described below and illustrated in the drawings are intended to teach the principles of the present disclosure, so that those skilled in the art are capable of implementing and using the present disclosure in a number of different environments and for a number of different applications.

[0050] Figures 1 and 2 show one embodiment of a display device 100, for example a liquid crystal display, according to the present disclosure, which comprises a rear housing 1 and a module middle frame assembly 2 and two exciters 3. In this embodiment, the sound emitting device 1 comprises a rear housing 1 and two exciters 3 mounted to the rear housing 1. The rear housing serves as a vibrating sound emitting plate, and the exciters generate vibrations by applying an electric current, for example an alternating current.

[0051] In particular, referring to Figure 3, the projection of the rear housing 1 on a horizontal plane is for example rectangular, and based on the direction facing the plane, the rear housing 1 defines a left side portion 11 and a right side portion 12 opposite the left side portion and has an inner side (i.e. the side facing the module middle frame assembly 2 in the mounted state) and an outer side opposite the inner side (facing the external environment), one exciter 3 being mounted on the inner side of the left side portion and the right side portion, respectively, to provide a two-channel (left and right channel) sound emitting device. It should be understood that other numbers of exciters, for example three, four, can be provided, arranged on the upper and lower side portions of the rear housing, and are equally covered by the scope of the present application.

[0052] In this embodiment, the exciters are mounted on the rear housing, using the rear housing as a vibrating sound emitting plate, and the risk of whole device vibration is reduced to avoid the influence of vibration on the (liquid crystal) display module. Furthermore, in order to enable more energy of the exciters to be concentrated on the vibrating part, meeting the requirement of vibrating sound emission, the peripheral area of the exciters is simple in structure, without reinforcing rib positions, and the area is as large as possible.

[0053] Figure 4 is an exploded view of the module middle frame assembly 2 according to one embodiment of the present disclosure. Figures 5 and 6 are rear view and cross-sectional view of the display device 100 according to one embodiment of the present disclosure. Referring to Figures 4 and 7, in one embodiment, the module middle frame assembly 2 includes a back plate 21, a middle frame 22, a display module 23, a power board 24, a main board 25, and a shield 26 for the power board and the main board. Advantageously, a vibration absorbing pad 20 (see Figure 7 in particular) is provided between the mating surface of the rear housing 1 and the middle frame 22 to absorb vibration so that other components do not move when the rear housing vibrates. In this context, the "mating surface" refers to the interface between the rear housing and the middle frame in the assembled state. In addition, the gap S between the exciter and the back plate is preferably not less than 1.5 mm to ensure that the exciter does not hit the back plate when it vibrates.

[0054] In a preferred embodiment, the "vibration absorbing pad" can also be referred to as a shock absorbing spacer, which can be made of ethylene-vinyl acetate copolymer (EVA). EVA has the characteristics of good softness, rubber-like elasticity, good flexibility at -50°C, transparency and surface gloss, good chemical stability, good anti-aging and ozone resistance, non-toxicity, and is widely used with low cost. Alternatively, the vibration absorbing pad can also be made of other suitable materials.

[0055] Figures 8 and 9 are top view and exploded view of one embodiment of the exciter according to the present disclosure. As can be seen from the figures, the exciter 3 can include an upper cover 31, a lower cover 32, a first shock absorbing washer 33 between the upper cover and the lower cover, a magnetic conducting bowl 34, a magnet 35, a voice coil 36, a flexible plug 37, and a second shock absorbing washer 39 and a buffer pad 38 fixedly connected to the lower side of the lower cover. This exciter structure is small and used to drive the rear housing to produce sound, which is a point sound. The first shock absorbing washer 33 and the second shock absorbing washer 39 can be made of shock absorbing foam, for example. The first shock absorbing washer is used to prevent the upper cover from hitting the lower cover during vibration to produce noise, and the second shock absorbing washer is used to prevent the lower cover from hitting the rear housing during vibration to produce noise. In addition, the shape of the first shock absorbing washer depends on the shape of the mating surface of the upper cover and the lower cover, which is shown as rectangular in the figures, and the shape of the second shock absorbing washer depends on the shape of the mating surface of the lower cover and the rear housing, which is shown as rectangular in the figures. The buffer pad is preferably made of silicone.

[0056] In this embodiment, the upper cover body 31 is configured to have a recess 310 on the side facing away from the lower cover body, for receiving the magnetic conducting bowl 34, which is fixed in the recess, for example, by adhesive, and functions to conduct magnetism and increase the magnetic field. The lower cover body and the upper cover body together define a containing chamber for receiving the magnet 35 and the voice coil 36. Furthermore, the left and right sides of the lower cover body 32 each has a mounting lug 320 in the form of an open ring and having a mounting hole 320a for receiving the first flexible plug 37 having a through hole 370. As shown in FIG. 9, the first flexible plug 37 is configured to have a hollow structure, which can be made of, for example, silicone, and has a cylindrical section and annular flange sections at both ends of the cylindrical section, wherein the outer diameter of the cylindrical section is smaller than the inner diameter of the mounting hole 320a, and the outer diameter of the annular flange sections is greater than the inner diameter of the mounting hole 320a, so that the flexible plug can be inserted into the mounting hole through the opening of the mounting lug, and the two annular flange sections of the flexible plug abut the upper and lower surfaces of the mounting lug, respectively.

[0057] Referring to FIG. 10, in the sound generating device according to the present disclosure, the inner side surface of the left side portion 11 and the inner side surface of the right side portion 12 of the rear housing 1 are each provided with two screw posts 11a, 12a having threaded blind holes, wherein each exciter 3 is connected to the rear housing 1 by sleeving the first flexible plug 37 on the corresponding screw post, and by screwing a threaded fastener 1a into the threaded blind hole of each screw post and abutting against the corresponding flexible plug. In this embodiment, by providing the screw posts, the rear housing can be avoided to be bored, thereby ensuring the integrity of the rear housing. In addition, the exciter 3 performs up-and-down reciprocating motion after being energized, and the vibration of the exciter is transmitted to the rear housing through the shock-absorbing pad at the bottom of the exciter. Since the exciter has a small size and the rear housing has a large size, the vibration of the exciter is transmitted to the rear housing, causing the rear housing to vibrate, thereby generating sound. Furthermore, since the lower side of the lower cover body of the exciter (i.e., the side to be mounted to the rear housing 1) is provided with a second shock-absorbing washer and a shock-absorbing pad, it can be ensured that the rear housing does not produce noise during the vibration of the exciter driving the vibration of the rear housing.

[0058] FIG. 10A shows the total harmonic distortion (THD) curve of the display device overall test acoustic using the above-mentioned dual-channel sound generating device. THD represents the degree of waveform distortion caused by all harmonics, and the lower the distortion, the more natural and realistic the sound. As shown in FIG. 10A, in the medium and high frequency band above 240 HZ, THD < 5%, and for the general consumer, distortion below 5% is almost inaudible. In the low frequency part, THD is relatively high, mainly from the amplitude of the exciter, and the distortion caused by the increase in amplitude is not considered here.

[0059] Figure 10B shows a display device whole machine test acoustic average loudness level (RMS) curve using the above-mentioned dual-channel sound production device; the RMS curve is the acoustic frequency response curve of the whole machine, the Y-axis is the sensitivity, the higher the better, and the X-axis is the frequency width, the lower the low frequency extension of the curve, the better. As shown in Figure 10B, the high frequency extension is not high, indicating that the mid-high frequency performance of the whole machine is medium or above.

[0060] Figure 11 shows a perspective view of a display device according to another embodiment of the present disclosure. The speaker used by the display device 100, such as a liquid crystal display, is mostly 3W-5W, and the requirement for sound is low, so many users who pursue sound will additionally equip the display with a separate sound box to improve the auditory experience. However, the separate sound box occupies desktop space and affects daily use. Therefore, in this embodiment, the sound production device 10 includes four exciters 3 arranged on the inner side surface of the rear shell 1 to replace the speaker sound production, i.e., to provide a four-channel sound production device. Specifically, the projection of the rear shell 1 in the horizontal plane is rectangular, and the rear shell 1 has four corner portions 1b, and one exciter 3 is mounted at the inner side surface of each corner portion.

[0061] Referring to Figures 12 and 13, in one embodiment of the sound production device 10, in order to mount the exciter 3 to the rear shell 1, the rear shell 1 is made of, for example, injection molding, and has a mounting seat 30 formed at each corner portion 1b and integrated with the rear shell, and the exciter 3 can be connected to the mounting seat 30 through a connecting mechanism, such as the connecting mechanism including a vibration plate 41, a first threaded fastener 42, a second threaded fastener 43, a flexible plug 44, and a third shock absorbing washer 45 arranged between the rear shell 1 and the vibration plate 41. Referring to Figure 14, specifically, the vibration plate 41 is configured as a rectangle and includes two first screw posts 411 having threaded blind holes and four second screw posts 412. The two first screw posts 411 are arranged along the length direction of the vibration plate, such as the longitudinal center line, and the four second screw posts 412 are arranged at the four corners of the vibration plate, respectively. Here, since the vibration plate is rectangular, the "longitudinal center line" of the vibration plate is defined as the center line along the length direction of the vibration plate.

[0062] In this embodiment, the exciter 3 is fitted onto the two first screw posts 411 by a first flexible plug 37 located in the mounting hole 320a, the shank of a first threaded fastener 42, such as a bolt, is inserted into the threaded blind hole of the first screw post 411. Referring to Fig. 14A, when the first threaded fastener 42 is locked in place, the lower surface of its head abuts against the upper surface of the first screw post, the first threaded fastener can no longer move downward, the flexible plug is compressed, for example, by 0.2 mm, to ensure that the exciter is fixed on the vibrating plate to form the exciter assembly 7 together with the vibrating plate. Also, the bumper pad 38 of the exciter 3 is compressed by 0.3 mm, ensuring the close contact of the exciter and the vibrating plate. When the exciter reciprocates up and down, i.e. the vibration of the exciter is transmitted to the vibrating plate through the bumper pad, the vibrating plate reciprocates up and down accordingly. In this embodiment, the vibrating plate 41 is used to replace the rear housing as the vibrating sound plate, which can better avoid the risk of whole machine vibration sound, and almost no other means of eliminating vibration sound is needed. Also, since the area of the rear housing is much larger than that of the vibrating plate in the exciter assembly 7, better bass effect can be achieved. Also, since the vibrating plates in each exciter assembly are independent of each other and do not interfere with each other, better sound localization can be achieved.

[0063] Referring again to Fig. 13, the mounting seat 30 includes a rectangular support portion 301 protruding inwardly from the inner side of the rear housing 1, which is used to support the exciter assembly 7, the rectangular support portion has a central opening 302 and assembly holes 303 located at the four corners of the rectangular support portion, preferably, the assembly holes 303 have a first circular hole portion 3031 and a second circular hole portion 3032 communicating with the first circular hole portion. The central opening is roughly cross-shaped, its shape depends on the shape of the exciter. Figs. 15-17 show the structural details of the mounting seat 30. On the back of the rectangular support portion 301, a first reinforcing rib 3021 and a second reinforcing rib 3022 extending towards the outer side of the rear housing 1 are provided, which improve the resonance frequency point of the rear housing and avoid the resonance caused by too poor strength of the rear housing. Specifically, the first reinforcing rib 3021 is formed around the central opening, i.e. its shape is the same as that of the central opening, and the second reinforcing rib 3022 is a plurality of reinforcing ribs extending from the first reinforcing rib to the rear housing and arranged along the circumference of the central opening.

[0064] Referring to FIGS. 19A and 19B, in one preferred embodiment of the present disclosure, the first flexible plug 37 and the second flexible plug 44 can be configured as hollow structures made of silicone, and have a cylindrical section 440 and annular flange sections 441 at both ends of the cylindrical section, wherein the outer diameter of the annular flange sections is smaller than the diameter of the first circular hole section 3031, and the outer diameter of the cylindrical section is equal to or smaller than the diameter of the second circular hole section, wherein the diameter of the first circular hole section is larger than the diameter of the second circular hole section. The first flexible plug and the second flexible plug are preferably made of silicone, but can also be made of other suitable materials, such as rubber, TPU, TPE, etc.

[0065] When the exciter assembly 7 is installed to the rear housing 1, the flexible plug 44 can be installed into the second circular hole section 3032 through the first circular hole section 3031. For example, in one example, the outer diameter of the annular flange sections 441 of the flexible plug 44 is 9.5 mm, and the diameter of the first circular hole section is 12 mm, so that the flexible plug can be easily sleeved into the first circular hole section; the outer diameter of the cylindrical section 440 of the flexible plug is 6.5 mm, and the diameter of the second circular hole section 3032 is also 6.5 mm, so that the cylindrical section of the flexible plug is just inserted into the second circular hole section, and the two annular flange sections abut against the inner and outer surfaces of the rectangular support section, respectively. Then, the second screw post 412 is inserted into the flexible plug 44, and the second threaded fastener 43 (see FIG. 18) is inserted into the threaded blind hole of the second screw post 412, and when the second threaded fastener 43 is locked in place, the lower surface of the head of the second threaded fastener abuts against the upper surface of the second screw post, and the second threaded fastener cannot move downward any more.

[0066] In one example, for example, the height of the flexible plug 44 before compression is 9 mm, and the height of the flexible plug after the second threaded fastener 43 is locked is 7.5 mm, at which time the flexible plug is compressed by 1.5 mm. The flexible plug is made of, for example, silicone and has a Shore hardness of 30 degrees, and when the exciter assembly 7 vibrates up and down, because the flexible plug has a hollow structure, the flexible plug can still be compressed by 4-5 mm in the extreme case, which ensures that the exciter assembly can move relative to the rear housing when vibrating without being hindered by the rear housing. At the same time, the third shock-absorbing washer 45 arranged between the rear housing and the vibration plate ensures that the vibration plate will not collide with the rear housing hard, avoiding the transmission of vibration to the rear housing.

[0067] In one preferred embodiment, the smaller the Young's modulus of the material of the vibration plate is, the louder the sound produced when vibrating is under the same power output condition. Because the Young's modulus of polystyrene material is small, the vibration plate 41 is preferably made of polystyrene material. However, it should be understood that the vibration plate can also be made of other suitable materials, which are also covered within the scope of the present disclosure.

[0068] Referring to FIG. 20 and FIG. 20A, the vibration sound production of the exciter is similar to the sound production of a loudspeaker, which is also to drive air to produce sound by a vibrating plate. The larger the surface area of the vibrating plate, the more air it can move, and to some extent, the louder the sound. However, the size of the vibrating plate is greatly affected by the overall appearance and structure of the machine, and cannot be increased indefinitely. Therefore, in the design, in order to make the surface area of the vibrating plate larger in a limited space, the vibrating plate is constructed with four pyramid structures 413 arranged on its upper surface facing the exciter. As can be seen from the figure, the upper surface of the vibrating plate is not covered with four pyramid structures. In the central part of the vibrating plate, such as the circular part 410, it is a flat structure without four pyramid structures 413, so as not to damage the buffer pad at the bottom of the exciter. After the structure is changed from a flat surface to a four-pyramid structure, the surface area is changed from a two-dimensional flat surface to a three-dimensional solid surface. The surface area of the vibrating plate is 1.41 times that of the flat structure. Under the condition of constant bottom area, the higher the four-pyramid, the larger the side surface area, and the louder the sound produced during vibration. However, the higher the four-pyramid, the thicker the vibrating plate, and the heavier the vibrating plate, which is not conducive to the vibration of the vibrating plate. When the four-pyramid is too small, it is difficult to injection mold and prone to lack of glue. Therefore, the height of the four-pyramid is preferably 0.5 mm.

[0069] FIG. 21 shows one embodiment of a display device 100, for example a liquid crystal display, according to the present disclosure, which comprises the four-channel sound production device described above. As can be seen from the figure, the display device 100 further comprises a display screen 5, a camera module 6, and a cover plate 8 for mounting the camera module 6 to the display screen. In this embodiment, the camera module 7 comprises a first camera module 61 located on the top side of the display screen, for vertical positioning of the display screen; a second camera module 62 located on the right side of the display screen, for horizontal positioning of the right half of the display screen; and a third camera module 63 located on the left side of the display screen, for horizontal positioning of the left half of the display screen.

[0070] In this embodiment, the camera module provided can identify and locate all things appearing in the picture in real time. The display device 100 further comprises a control system configured to: when detecting that there is a sound signal output, the camera module starts to scan the display screen for the first time and divides the display area of the display screen into nine areas evenly, for example, the coordinates are (1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 3), (3, 1), (3, 2), (3, 3) (see FIG. 22); and compare the sound with the category and action of things in each area one by one to confirm the relationship to confirm in which area the sound occurs and control the corresponding exciter to sound. Preferably, the camera module can also perform a second scan, which will further divide the confirmed area into 9 sub-areas, and reset the coordinates of the 9 sub-areas, and again accurately determine the position where the sound occurs.

[0071] When a person hears a sound, he can determine the position of the sound source according to the phase difference of the sound between the left ear and the right ear, which is the basis for the design of multi-channel surround sound. The above-mentioned display device of the present disclosure is also based on this principle, through acoustic tuning, the exciter assembly located at the four corners of the rear shell can adjust the sound loudness and sound wave delay, phase shift in real time according to the actual music, forming a 4.0 channel surround sound effect. Combined with the real-time positioning function of the camera module, the sound is played from the actual sound source.

[0072] For example, there is a person speaking in the picture, the control system will judge the age and gender of the speaker, and at the same time scan the screen to determine the position of the speaker. Assuming that through scanning and identification, it is determined that the speaker is located at coordinate (1, 2), at this time the exciter assemblies located at the upper left corner and the upper right corner will sound, and the sound signals of the two are completely identical, that is, the sound intensity difference, phase difference and frequency difference of the two are completely identical, at this time the sound image synthesized by the two will come out from coordinate (1, 2), that is, the sound feels to be emitted from coordinate (1, 2). When it is determined that the coordinate of the speaker is (2, 2), the exciter assemblies located at the upper left corner and the lower right corner (or the exciter assemblies located at the lower left corner and the upper right corner) will sound, and the sound signals of the two are completely identical, that is, the sound intensity difference, phase difference and frequency difference of the two are completely identical, at this time the sound image synthesized by the two will come out from coordinate (2, 2), that is, the sound feels to be emitted from coordinate (2, 2). In fact, by adjusting the sound intensity difference and phase difference of the sound waves emitted by the exciters at different positions, the position of the synthesized sound image can be more accurately adjusted.

[0073] It should be noted that the above description is only exemplary, and those skilled in the art can make various modifications and variations to the embodiments of the present disclosure according to the above description, and these modifications and variations are all within the protection scope of the present disclosure.

Claims

1. A sound emitting device for a display device, the display device comprising a back housing having an inner side facing a module middle frame assembly, and a module middle frame assembly, wherein, The sound production device comprises the rear housing and at least one exciter mounted to the inner side of the rear housing.

2. The sound production device of claim 1, wherein, The rear housing comprises a left side and an opposite right side, and one of the exciter is mounted to the left side and the right side respectively.

3. The sound production device of claim 2, wherein, The module middle frame assembly comprises a back plate, a middle frame and a display module, and a vibration absorption pad is arranged between the mating surface of the rear housing and the middle frame, and the gap between the exciter and the back plate is not less than 1.5mm.

4. The sound production device of claim 2 or 3, wherein, The exciter comprises: an upper cover body; a lower cover body, the left and right sides of the lower cover body are respectively provided with one mounting lug, each of the mounting lugs is provided with a mounting hole; a first shock absorbing washer located between the upper cover body and the lower cover body; a first flexible plug located in the corresponding mounting hole, the first flexible plug is provided with a through hole; and a second shock absorbing washer and a buffer pad fixedly connected to the side of the lower cover body away from the upper cover body.

5. The sound production device of claim 4, wherein, The inner side of the left side and the inner side of the right side are respectively provided with two screw posts with threaded blind holes, and the exciter is connected to the rear housing through the cooperation of the first flexible plug, the corresponding screw post and the threaded fastener.

6. The sound production device of claim 1, wherein, The rear housing has four corner portions, and one of the excitors is mounted to the inner side of each of the corner portions.

7. The sound production device of claim 6, wherein, The rear housing has a mounting seat integrally formed at each of the corner portions, and the exciter is connected to the mounting seat through a connecting mechanism, wherein the connecting mechanism comprises: a vibration plate comprising a first screw post and a second screw post with threaded blind holes; a first threaded fastener connecting the exciter to the vibration plate through cooperation with the threaded blind hole of the first screw post; a second threaded fastener connecting the vibration plate to the mounting seat through cooperation with the threaded blind hole of the second screw post; and a second flexible plug sleeved on each of the second screw posts, the second flexible plug is provided with a through hole.

8. The sound production device according to claim 7, wherein the connecting mechanism further comprises a third shock absorbing washer arranged between the rear housing and the vibration plate; wherein the vibration plate has four second screw posts located at the four corners of the vibration plate, and two first screw posts arranged at intervals along the length direction of the vibration plate; and the mounting seat comprises a rectangular supporting portion protruding inwardly from the inner side of the rear housing, the rectangular supporting portion is provided with a central opening and a fitting hole located at each of the four corners of the rectangular supporting portion, and the flexible plug and the second screw post are mounted to the mounting seat through the fitting hole.

9. The sound production device of claim 8, wherein, The fitting hole has a first circular hole portion and a second circular hole portion in communication with the first circular hole portion; the second flexible plug is a hollow member and has a cylindrical section and annular flange portions located at both ends of the cylindrical section, wherein the outer diameter of the annular flange portion is smaller than the diameter of the first circular hole portion, and the outer diameter of the cylindrical section is smaller than or equal to the diameter of the second circular hole portion, and the diameter of the first circular hole portion is larger than the diameter of the second circular hole portion.

10. The sound production device of claim 8, wherein, The rectangular supporting part has a first reinforcing rib and a second reinforcing rib extending towards the outer side surface of the rear shell.

11. The sound production device of any one of claims 7 to 10, wherein, An upper surface of the vibrating plate facing the exciter has a quadrangular pyramid structure.

12. The sound production device of any one of claims 6 to 10, wherein, The exciter comprises: an upper cover body; a lower cover body, the left and right sides of the lower cover body each having an installation lug, each installation lug having an installation hole; a first shock-absorbing washer between the upper cover body and the lower cover body; a first flexible plug in the corresponding installation hole, the first flexible plug having a through hole; and a second shock-absorbing washer and a buffer pad fixedly connected to the lower side of the lower cover body.

13. A display device comprising the sound production device according to any one of claims 1 to 12.

14. The display device of claim 13, wherein, The display device further comprises a display screen, a camera module, and a cover plate for mounting the camera module to the display screen, the camera module comprising: a first camera module on the top side of the display screen for vertical positioning of the display screen; a second camera module on the right side of the display screen for horizontal positioning of the right half of the display screen; and a third camera module on the left side of the display screen for horizontal positioning of the left half of the display screen.

15. The display device according to claim 14, further comprising a control system configured to: when detecting that there is a sound signal output, the camera module starts to scan the display screen for the first time and evenly divides the display area of the display screen into nine areas in three rows and three columns; and compares the sound with the category and action of the things in each area one by one to confirm the relationship, to confirm in which area the sound occurs, and to control the corresponding exciter to produce sound. ​

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