Vibration generation device

Abstract

This vibration generation device comprises: a housing including a lower case on which a coil is placed and an upper case; a movable body that includes a magnet, and a yoke disposed on the upper side of the magnet, is disposed on the upper side of the coil so as to face the coil, and vibrates in a first direction with respect to the housing; and a pair of elastic arm parts that are disposed one on each side of the movable body in the first direction and connected to the housing and the movable body on the upper side of the lower case. The upper case has a frame part that exposes the movable body at a central portion while covering the pair of elastic arm parts.

Description

Vibration generating device

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[0008] , ,

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[0001] The present invention relates to a vibration generating device.

[0002] Conventionally, a vibration generating device that generates vibration using a magnet has been known. In such a vibration generating device, vibration is generated by a movable body including a magnet reciprocating in one direction. However, when an impact such as dropping occurs, it is preferable to prevent the movable body from moving more than expected.

[0003] Patent Document 1 discloses a configuration in which a pair of left and right restricting portions are provided on each of a top surface portion and a bottom wall portion that are opposed to a vibrating body in a separated state, thereby preventing excessive vibration of the vibrating body. <00000​​​​​​​​​​​​​​​​According to the present invention, it is possible to achieve a thinner design while protecting the elastic arm that supports the movable body so that it can vibrate in the direction of vibration.

[0010] This is an external perspective view of the vibration generator. This is an exploded perspective view of the vibration generator shown in Figure 1. This is an external perspective view of the upper case shown in Figures 1 and 2, viewed from diagonally above. This is an external perspective view of the upper case shown in Figures 1 and 2, viewed from diagonally below. This is a cross-sectional view taken along line B-B shown in Figure 3. This is an external perspective view of the elastic member shown in Figure 2, viewed from diagonally above. This is an external perspective view of the yoke shown in Figures 1 and 2, viewed from diagonally above. This is a cross-sectional view taken along line C-C shown in Figure 7. This is a top view of the magnet shown in Figure 2. This is a view of the magnet shown in Figure 2 from the X1 direction. This is a top view of the coil body and conductive member shown in Figure 2. This is an external perspective view of the lower case to which the connecting member shown in Figure 2 is attached, viewed from diagonally above. This is a diagram showing the positional relationship between the upper case and the elastic member. This is a diagram showing the positional relationship between the protrusion of the upper case and the protrusion of the yoke. This is a diagram showing the positional relationship between the protrusion of the upper case and the protrusion of the yoke. This is an external perspective view to explain the method of fixing the elastic member to the yoke. This is an enlarged view of the part of the elastic member that is fixed to the yoke. This is a diagram showing the relationship between the magnet and the coil. This is a diagram to explain the operation of the vibration generator 1. This is a diagram to explain the operation of the vibration generator 1. This is a diagram illustrating the operation of the vibration generator 1.

[0011] Embodiments of the present invention will be described below with reference to the drawings.

[0012] (Overall Configuration) First, let me explain the overall configuration of the vibration generating device.

[0013] Figure 1 is an external perspective view of the vibration generator 1. Figure 2 is an exploded perspective view of the vibration generator 1 shown in Figure 1.

[0014] In Figures 1 and 2, X1 represents one direction of the X-axis in a three-dimensional Cartesian coordinate system, and X2 represents the other direction of the X-axis. Similarly, Y1 represents one direction of the Y-axis in a three-dimensional Cartesian coordinate system, and Y2 represents the other direction. Likewise, Z1 represents one direction of the Z-axis in a three-dimensional Cartesian coordinate system, and Z2 represents the other direction of the Z-axis. In this embodiment, the X1 side of the vibration generator 1 corresponds to the front side of the vibration generator 1, and the X2 side of the vibration generator 1 corresponds to the rear side of the vibration generator 1. The Y1 side of the vibration generator 1 corresponds to the left side of the vibration generator 1, and the Y2 side of the vibration generator 1 corresponds to the right side of the vibration generator 1. The Z1 side of the vibration generator 1 corresponds to the top side of the vibration generator 1, and the Z2 side of the vibration generator 1 corresponds to the bottom side of the vibration generator 1. The same applies to the other figures.

[0015] Note that the X-axis direction is an example of a second direction, and the Y-axis direction is an example of a first direction.

[0016] As shown in Figures 1 and 2, the vibration generator 1 has a housing HS, and a movable body MB, an elastic member 30, and a coil body 60 are arranged inside the housing HS. The housing HS is an example of a housing in the present invention and has an upper case 10 and a lower case 20. An opening 15 is provided in the center of the upper case 10, and the movable body MB is exposed through this opening 15. A connecting member 80 is attached to the lower case 20, and the vibration generator 1 is electrically connected to the control unit 2 via the connecting member 80. The movable body MB is composed of a yoke 40 and a magnet 50.

[0017] (Upper Case 10) Figure 3 is an external perspective view of the upper case 10 shown in Figures 1 and 2, viewed from diagonally above. Figure 4 is an external perspective view of the upper case 10 shown in Figures 1 and 2, viewed from diagonally below. Figure 5 is a cross-sectional view taken along line B-B in Figure 3.

[0018] The upper case 10 is made of a non-magnetic metal plate material such as stainless steel, and as shown in Figures 3 to 5, it has a frame portion 11, side wall portions 13a to 13d, bottom wall portions 16a to 16d, and protruding portions 12a and 12b.

[0019] The frame portion 11 is configured in a frame shape with an opening 15 in the center. Of the inner edge portions 11a to 11d on the opening 15 side, two inner edge portions 11a and 11b that face each other in the Y-axis direction have plate-shaped protrusions 12a and 12b that protrude in the Z2 direction (downward) by bending the frame portion 11 into an L-shape. The protrusions 12a and 12b are examples of the first protrusions in the present invention and are provided in the center of the upper case 10 in the X-axis direction, and their protrusion height is lower than the height of the side wall portions 13a to 13d.

[0020] The side wall portions 13a to 13d each protrude in the Z2 direction (downward) from the outer edge of the frame portion 11, and of these, only the side wall portion 13c is provided with an opening 14. The opening 14 is for bringing the connection made by the connecting member 80 attached to the lower case 20 out from the inside to the outside of the housing HS.

[0021] The bottom wall portions 16a to 16d are bent in the Z2 direction (downward) of the side wall portions 13a to 13d so as to be parallel to the frame portion 11, and are continuous with the side wall portions 13a to 13d. The upper case 10 is fixed to the lower case 20 by attaching these bottom wall portions 16a to 16d to the lower case 20 by welding or the like.

[0022] (Elastic member 30) Figure 6 is an external perspective view of the elastic member 30 shown in Figure 2, viewed from diagonally above.

[0023] The elastic member 30 is made of a non-magnetic metal plate material such as stainless steel, and as shown in Figure 6, it has two elastic members 30a and 30b.

[0024] The elastic member 30a has a pair of elastic arms 31a and 32a at both ends, which are curved in the XY plane and parallel to the Z axis, and these pair of elastic arms 31a and 32a are connected via a connecting portion 33a.

[0025] The connecting portion 33a is an elongated plate shape with its surface facing the X-axis direction and extending in the Y-axis direction. The connecting portion 33a is provided with an overhang portion 34a. The overhang portion 34a is an example of a second overhang portion in the present invention. The overhang portion 34a is constructed by bending the plate surface from the Z1 side end of the connecting portion 33a so that it faces the Z-axis direction. The overhang portion 34a is provided with a positioning hole 35a.

[0026] The elastic arms 31a and 32a are elongated plates with a surface parallel to the Z-axis. They bend in the X2 direction from both ends of the connecting portion 33a, then bend while curving in the Y1 or Y2 direction, and then bend in the X1 direction. The elastic arm 31a is provided with a fixing portion 36a near the end opposite to the connecting portion 33a, which is fixed to the upper case 10 by welding or the like. The elastic arm 32a is also provided with a fixing portion 37a near the end opposite to the connecting portion 33a, which is fixed to the upper case 10 by welding or the like.

[0027] The elastic member 30b is made of the same material and has the same shape as the elastic member 30a. Like the elastic member 30a, it has a pair of elastic arms 31b and 32b at both ends that are curved in the XY plane and parallel to the Z axis. These pairs of elastic arms 31b and 32b are connected via a connecting portion 33b.

[0028] The connecting portion 33b is an elongated plate with its surface facing the X-axis and extending in the Y-axis direction. The connecting portion 33b is provided with an overhang portion 34b. The overhang portion 34b is an example of a second overhang portion in the present invention. The overhang portion 34b is constructed by bending the plate surface from the Z1 side end of the connecting portion 33b so that it faces the Z-axis direction. The overhang portion 34b is provided with a positioning hole 35b.

[0029] The elastic arms 31b and 32b are elongated plates with a plate surface parallel to the Z-axis. They bend in the X1 direction from both ends of the connecting portion 33b, then bend while curving in the Y1 or Y2 direction, and then bend in the X2 direction. The elastic arm 31b is provided with a fixing portion 36b near the end opposite to the connecting portion 33b, which is fixed to the upper case 10 by welding or the like. The elastic arm 32b is also provided with a fixing portion 37b near the end opposite to the connecting portion 33b, which is fixed to the upper case 10 by welding or the like.

[0030] The elastic member 30 configured in this way is attached to the side walls 13a and 13b of the upper case 10 by welding or the like via the fixing parts 36a and 37a, with the elastic member 30a fixed to the side walls 13a and 13b of the upper case 10 by welding or the like via the fixing parts 36b and 37b. Then, as the elastic arms 31a, 31b, 32a and 32b elastically deform, the yoke 40, which is attached to the protruding parts 34a and 34b by welding or the like, is made vibrable in the Y-axis direction together with the magnet 50.

[0031] Furthermore, elastic arms 31a and 32a correspond to the first pair of elastic arms in the present invention, and elastic arms 31b and 32b correspond to the second pair of elastic arms.

[0032] (Yoke 40) Figure 7 is an external perspective view of the yoke 40 shown in Figures 1 and 2, viewed from diagonally above. Figure 8 is a cross-sectional view taken along line C-C in Figure 7.

[0033] The yoke 40 is made of a ferromagnetic metal plate and, as shown in Figures 7 and 8, has a flat portion 41, protruding portions 42a to 42d, and overhanging portions 43c and 43d.

[0034] The flat plate portion 41 is a rectangular plate with the same outer shape as the magnet 50, and protrusions 42a to 42d protrude in the Z2 direction (downward) from each of the outer edges 41a to 41d. Each of the protrusions 42a to 42d is made up of a plate, and among these, protrusions 42a and 42b that face each other in the Y-axis direction are an example of the second protrusion in the present invention.

[0035] The protruding portions 43c and 43d are examples of the first protruding portions in the present invention. The protruding portions 43c and 43d have a plate-like shape with a planar portion facing the Z-axis direction, and protrude outward in the X-axis direction from each of the two outer edges 41c and 41d of the outer edges 41a to 41d of the flat plate portion 41, which are the end edges of the flat plate portion 41 in the X-axis direction. As a result, the protruding portions 43c and 43d protrude from the magnet 50 when the flat plate portion 41 of the yoke 40 is superimposed on the magnet 50, as will be described later. Positioning notches 44c and 44d are provided in the protruding portions 43c and 43d, respectively.

[0036] The protruding portion 43c of the yoke 40, configured in this way, is attached to the protruding portion 34a of the elastic member 30a by welding or the like, thereby fixing the elastic member 30a to the yoke 40. Similarly, the protruding portion 43d of the yoke 40 is attached to the protruding portion 34b of the elastic member 30b by welding or the like, thereby fixing the elastic member 30b to the yoke 40. As a result, the elastic members 30a and 30b can be easily attached and fixed to the yoke 40 without adding any new parts.

[0037] (Magnet 50) Figure 9 is a top view of the magnet 50 shown in Figure 2. Figure 10 is a view of the magnet 50 shown in Figure 2 from the X1 direction.

[0038] The magnet 50 is a rectangular plate with the same outer shape as the flat plate portion 41 of the yoke 40, and is arranged so that its flat surface faces the Z-axis direction. As shown in Figure 9, the magnet 50 has a plurality of magnetic pole portions 51a to 51f, and the surfaces of adjacent magnetic pole portions 51a to 51f have different polarities. The magnetic pole portions 51a to 51f are arranged in line along the Y-axis direction. The plurality of magnetic pole portions 51a to 51f have different polarities on their front and back sides, and as shown in Figure 10, the magnetic pole portion 51a has an upper magnetic pole portion 51aU and a lower magnetic pole portion 51aD. The magnetic pole portion 51b has an upper magnetic pole portion 51bU and a lower magnetic pole portion 51bD. The magnetic pole portion 51c has an upper magnetic pole portion 51cU and a lower magnetic pole portion 51cD. Furthermore, the magnetic pole portion 51d has an upper magnetic pole portion 51dU and a lower magnetic pole portion 51dD. Furthermore, the magnetic pole portion 51e has an upper magnetic pole portion 51eU and a lower magnetic pole portion 51eD. Furthermore, the magnetic pole portion 51f has an upper magnetic pole portion 51fU and a lower magnetic pole portion 51fD.

[0039] The magnet 50 configured in this way is held in the yoke 40 by magnetic attraction to the flat plate portion 41 of the yoke 40.

[0040] (Coil body 60 and conductive member 62) Figure 11 is a top view of the coil body 60 and conductive member 62 shown in Figure 2.

[0041] As shown in Figure 2, the coil body 60 is composed of two coils 61a and 61b, and as shown in Figure 11, the conductive member 62 is composed of two conductive members 62a and 62b.

[0042] The two coils 61a and 61b are arranged side by side in the Y-axis direction. Coil 61a has two bundled sections 63a and 64a extending in the X-axis direction, and two curved sections 65a and 66a connecting the bundled sections 63a and 64a. On the other hand, coil 61b has two bundled sections 63b and 64b extending in the X-axis direction, and two curved sections 65b and 66b connecting the bundled sections 63b and 64b. The two coils 61a and 61b configured in this way are arranged adjacent to each other in the Y-axis direction such that the bundled sections 63a and 64a and the bundled sections 63b and 64b are parallel to each other, and are fixed to the lower case 20 by double-sided tape or the like.

[0043] The conductive members 62a and 62b are elongated plate-shaped members extending in the X-axis direction, and are arranged such that their planar portions face the Z-axis direction. The conductive members 62a and 62b are arranged at positions sandwiching the two coils 61a and 61b in the Y-axis direction. The thickness of the conductive members 62a and 62b in the Z-axis direction may be equal to the thickness of the coils 61a and 61b in the Z-axis direction.

[0044] When the movable body MB moves along the Y-axis direction, the conductive members 62a and 62b are configured such that an induced electromotive force (eddy current) is generated due to the change in magnetic flux crossing the conductive members 62a and 62b, and a braking force is generated on the movable body MB. The conductive members 62a and 62b are fixed to the lower case 20 by means of a double-sided tape, an adhesive, caulking, or the like. Typically, the conductive members 62a and 62b are formed of a non-magnetic metal. This configuration can prevent a magnetic force (attractive force) from acting between the conductive members 62a and 62b and the magnet 50 as in the case where the conductive members 62a and 62b are formed of a magnetic metal, and can suppress the efficient utilization of the driving force for vibrating the movable body MB being hindered by such an attractive force. Also, the conductive members 62a and 62b typically contain a material having a higher conductivity than that of the upper case 10 or the lower case 20. For example, the conductive members 62a and 62b are formed of a material having a higher conductivity than iron or an iron alloy. This configuration provides the effect of increasing the braking force (the force that suppresses the vibration of the movable body MB) caused by eddy currents. This is because the greater the conductivity, the greater the eddy current that can be generated, and the greater the braking force due to the eddy current. Note that since the conductive members 62a and 62b have the effect of damping the vibration of the movable body MB (damping effect), they are also called "damping members".

[0045] Also, the conductive members 62a and 62b are typically configured as separate and independent components from the lower case 20 rather than being a part of the lower case 20. This configuration provides the effect that even when the lower case 20 is formed of a non-conductive material, the braking force caused by eddy currents can be utilized to damp the vibration of the movable body MB.

[0046] In the illustrated example, the conductive members 62a and 62b are copper plates and are directly fixed to the lower case 20 by double-sided tape. Note that the conductive members 62a and 62b may be formed including copper or aluminum. For example, the conductive members 62a and 62b may be formed of copper, aluminum, or an alloy thereof. This configuration provides an effect of reducing material costs as compared with the case where the conductive members 62a and 62b are formed of a noble metal such as silver or an alloy thereof.

[0047] As shown in FIG. 18, for example, the coil body 60 may be arranged such that the bundled portion 63a of the coil 61a faces the magnetic pole portion 51bD of the magnet 50, the bundled portion 64a of the coil 61a faces the magnetic pole portion 51cD of the magnet 50, the bundled portion 63b of the coil 61b faces the magnetic pole portion 51dD of the magnet 50, and the bundled portion 64b of the coil 61b faces the magnetic pole portion 51eD of the magnet 50. In that case, the conductive member 62a may be arranged to face the magnetic pole portions 51aD and 51bD of the magnet 50, and the conductive member 62b may be arranged to face the magnetic pole portions 51eD and 51fD of the magnet 50.

[0048] (Lower Case 20) FIG. 12 is an external perspective view of the lower case 20 to which the connection member 80 shown in FIG. 2 is attached, viewed obliquely from above.

[0049] The lower case 20 is made of a non-magnetic metal plate material such as stainless steel, and as shown in FIG. 12, two hole portions 22 are formed in the flat plate portion 21. The connection member 80 is fixed in the vicinity of the hole portion 22 on one surface of the flat plate portion 21 by double-sided tape or the like.

[0050] The connecting member 80 is constructed on an FPC substrate 81, with terminals 82a, 82b, 83a to 83d provided and wiring 84a, 84b formed thereon. Terminals 82a and 82b are for connecting the vibration generator 1 to the control unit 2, and wiring (not shown) connected to the control unit 2 is connected to them. Terminals 83a to 83d are connected to both ends of the conductors of coils 61a and 61b. Wiring 84a connects terminal 82a to terminals 83a and 83b. Wiring 84b connects terminal 82b to terminals 83c and 83d. The holes 22 allow the wiring (not shown) connected to terminals 83a to 83d to enter when connecting it to coils 61a and 61b, depending on the thickness of the wiring. With this connection, coils 61a and 61b are connected in parallel, and current flows in different directions in the X-axis direction through adjacent bundled sections, i.e., bundled sections 63a and 64a, or bundled sections 64a and 63b, or bundled sections 63b and 64b.

[0051] The coil body 60 and conductive member 62 are placed on the lower case 20 configured as described above, and the coil body 60 and conductive member 62 are fixed to the flat plate portion 21 of the lower case 20 by double-sided tape or the like.

[0052] (Positional relationship between upper case 10 and elastic member 30) Figure 13 shows the positional relationship between the upper case 10 and the elastic member 30, and is viewed from the Z2 direction.

[0053] As described above, the elastic arm portion 31a of the elastic member 30a is provided with a fixing portion 36a near the end opposite to the connecting portion 33a, which is fixed to the upper case 10 by welding or the like. Similarly, the elastic arm portion 32a is also provided with a fixing portion 37a near the end opposite to the connecting portion 33a, which is fixed to the upper case 10 by welding or the like.

[0054] Therefore, as shown in Figure 13, the elastic member 30a has an elastic arm portion 31a attached to the side wall portion 13a of the upper case 10 by welding or the like at the fixing portion 36a, and an elastic arm portion 32a attached to the side wall portion 13b of the upper case 10 by welding or the like at the fixing portion 37a.

[0055] Furthermore, as described above, the elastic arm portion 31b of the elastic member 30b is provided with a fixing portion 36b near the end opposite to the connecting portion 33b, which is fixed to the upper case 10 by welding or the like. The elastic arm portion 32b is also provided with a fixing portion 37b near the end opposite to the connecting portion 33b, which is fixed to the upper case 10 by welding or the like.

[0056] Therefore, as shown in Figure 13, the elastic member 30b has an elastic arm portion 31b attached to the side wall portion 13a of the upper case 10 by welding or the like at the fixing portion 36b, and an elastic arm portion 32b attached to the side wall portion 13b of the upper case 10 by welding or the like at the fixing portion 37b.

[0057] In this state, with the elastic members 30a and 30b attached to the upper case 10, as is clear from Figure 13, the elastic arms 31a and 31b and the connecting portion 33a of the elastic member 30a are covered by the frame portion 11 of the upper case 10. It is not necessarily required that all of the elastic arms 31a and 31b are covered so that they are not exposed from the opening 15 when viewed from the Z1 direction; some of the elastic arms 31a and 31b may protrude slightly from the frame portion 11. This protects the elastic members 30a and 30b from external forces, etc.

[0058] (Positional relationship between the protrusions 12a and 12b of the upper case 10 and the protrusions 42a and 42b of the yoke 40) Figure 14 is a diagram showing the positional relationship between the protrusions 12a and 12b of the upper case 10 and the protrusions 42a and 42b of the yoke 40, and is a view from the Z1 direction. Note that in Figure 14, only the protrusions 12a and 12b of the upper case 10 are shown. Figure 15 is a diagram showing the positional relationship between the protrusions 12a and 12b of the upper case 10 and the protrusions 42a and 42b of the yoke 40, and is a cross-sectional view taken along line A-A as shown in Figure 1.

[0059] As described above, the elastic member 30a has an elastic arm 31a attached to the side wall 13a of the upper case 10 by welding or the like at the fixing part 36a, and an elastic arm 32a attached to the side wall 13b of the upper case 10 by welding or the like at the fixing part 37a. Similarly, the elastic member 30b has an elastic arm 31b attached to the side wall 13a of the upper case 10 by welding or the like at the fixing part 36b, and an elastic arm 32b attached to the side wall 13b of the upper case 10 by welding or the like at the fixing part 37b.

[0060] Furthermore, as described above, the elastic member 30a is fixed to the yoke 40 by welding or the like to the protruding portion 34a of the elastic member 30a, where the protruding portion 43c of the yoke 40 is attached to the protruding portion 34a of the elastic member 30a. Also, the elastic member 30b is fixed to the yoke 40 by welding or the like to the protruding portion 34b of the elastic member 30b, where the protruding portion 43d of the yoke 40 is attached to the protruding portion 34b of the elastic member 30b.

[0061] In this state, with the elastic members 30a and 30b attached to the yoke 40 and then attached to the upper case 10, as shown in Figures 14 and 15, the protrusion 12a of the upper case 10 faces the protrusion 42a of the yoke 40, and the protrusion 12b of the upper case 10 faces the protrusion 42b of the yoke 40.

[0062] In this embodiment, the vibration generator 1 is configured such that the movable body MB, consisting of a yoke 40 and a magnet 50, can vibrate in the Y-axis direction, as will be described later. Therefore, if the vibration generator 1 is subjected to an impact greater than expected, such as a fall, there is a risk that the movable body MB may move significantly in the Y-axis direction.

[0063] However, in the vibration generator 1 of this embodiment, the protrusion 12a of the upper case 10 faces the protrusion 42a of the yoke 40, and the protrusion 12b of the upper case 10 faces the protrusion 42b of the yoke 40. Therefore, even if the vibration generator 1 is subjected to an impact greater than expected, such as a fall, and the movable body MB, consisting of the yoke 40 and the magnet 50, tries to move significantly in the Y-axis direction, the protrusions 12a and 12b of the upper case 10 come into contact with the protrusions 42a and 42b of the yoke 40, acting as stoppers and preventing the movable body MB, consisting of the yoke 40 and the magnet 50, from moving further in the Y-axis direction. As a result, for example, the elastic arms 31a, 32a, 31b, and 32b of the elastic members 30a and 30b do not bend excessively beyond their spring limit, nor do they come into contact with the conductive member 62 or the coil body 60 and cause damage.

[0064] Furthermore, as shown in Figures 3 and 14, the protrusion 12a of the upper case 10 is located in the central part of the upper case 10 in the X-axis direction, and elastic arms 31a and 31b are positioned on each of the two sides of the protrusion 12a in the X-axis direction. Similarly, the protrusion 12b of the upper case 10 is located in the central part of the upper case 10 in the X-axis direction, and elastic arms 32a and 32b are positioned on each of the two sides of the protrusion 12b in the X-axis direction. Therefore, the protrusions 12a and 12b can be positioned in the region between the elastic arms 32a and 32b, and in the region between the elastic arms 31a and 31b, resulting in good space efficiency. Note that the entire protrusions 12a and 12b do not necessarily need to be positioned in the region between the elastic arms 31a and 31b in the X-axis direction, as the elastic arms 31a and 31b are curved, and the ends of the protrusions 12a and 12b may overlap with the elastic arms 31a and 31b in the X-axis direction. Furthermore, even if the vibration generator 1 is subjected to an impact greater than expected, such as a fall, causing the movable body MB to move in the Y-axis direction until the protrusions 42a and 42b of the yoke 40 come into contact with the protrusions 12a and 12b of the upper case 10, and the elastic arms 31a and 31b are deformed, the protrusions 12a and 12b of the upper case 10 are positioned such that they do not overlap with the protrusions 12a and 12b of the upper case 10 in the XY plane. Therefore, the elastic arms 31a and 31b will not come into contact with the protrusions 12a and 12b of the upper case 10.

[0065] Furthermore, the protruding portions 12a and 12b of the upper case 10 are positioned in a region where the surface facing the opening 15 of the frame portion 11 does not overlap with the elastic arm portions 31a, 31b, 32a, and 32b in the Y-axis direction. That is, as shown in Figure 13, the surface of the protruding portion 12a facing the opening 15, i.e., the Y2 side surface, does not overlap with the region where the elastic arm portions 31a and 31b are formed in the Y-axis direction, and is located closer to the center (Y2 side) of the opening 15. Similarly, the surface of the protruding portion 12b facing the opening 15, i.e., the Y1 side surface, does not overlap with the region where the elastic arm portions 32a and 32b are formed in the Y-axis direction, and is located closer to the center (Y1 side) of the opening 15. Therefore, if the vibration generator 1 is subjected to an impact greater than expected, such as a fall, the elastic arms 31a, 31b, 32a, and 32b do not obstruct the protrusions 12a and 12b, allowing the protrusions 12a and 12b of the upper case 10 to come into contact with the protrusions 42a and 42b of the yoke 40.

[0066] Here, the protrusions 12a and 12b of the upper case 10, which act as stoppers to restrict the movement of the movable body MB in the Y-axis direction, are formed by bending the frame portion 11 into an L-shape. This makes it possible to increase the rigidity of the plate-shaped upper case 10. Furthermore, the protrusions 12a and 12b of the upper case 10 protrude in the Z2 direction (downward) from the inner edges 11a and 11b on the opening 15 side of the frame portion 11, respectively. Therefore, in order to restrict the movement of the movable body MB in the Y-axis direction beyond what is expected, it is sufficient to bring the protrusions 42a and 42b that protrude in the Z2 direction (downward) from the outer edges 41a and 41b of the yoke 40, respectively, into contact with the protrusions 12a and 12b of the upper case 10. As a result, compared to a design where the side walls 13a and 13b of the upper case 10 act as stoppers, there is no need to provide a member on the outside of the yoke 40 in the Y-axis direction to contact the side walls 13a and 13b of the upper case 10, thus avoiding structural complexity. Furthermore, it is preferable to secure an area in the lower case 20 for attaching the coil body 60 with double-sided tape or the like, but since the upper case 10 is provided with protrusions 12a and 12b that act as stoppers, an area for attaching the coil body 60 with double-sided tape or the like can be secured in the lower case 20.

[0067] Furthermore, in the vibration generator 1 of this embodiment, the movable body MB is exposed through the opening 15 of the upper case 10. As a result, the upper case 10 does not exist on the movable body MB, and the entire vibration generator 1 can be made thinner. In this case, the height of the upper surface of the movable body MB may be the same as the height of the upper surface of the frame portion 11 of the upper case 10, or the height of the upper surface of the movable body MB may be higher than the height of the upper surface of the frame portion 11 of the upper case 10.

[0068] (Fixing of the elastic member 30 to the yoke 40) Figure 16 is an external perspective view illustrating the method of fixing the elastic member 30 to the yoke 40. Figure 17 is an enlarged view of the part of the elastic member 30 that is fixed to the yoke 40. Note that in Figure 17, the yoke 40 is shown as if viewed through a glass hole.

[0069] As described above, the elastic member 30a is fixed to the yoke 40 by welding or other means to the protruding portion 43c of the yoke 40 and the protruding portion 34a of the elastic member 30a. Similarly, the elastic member 30b is fixed to the yoke 40 by welding or other means to the protruding portion 43d of the yoke 40 and the protruding portion 34b of the elastic member 30b.

[0070] In this process, as shown in Figure 16, the yoke 40 and the elastic member 30a are aligned by aligning the alignment notch 44c provided in the protruding portion 43c of the yoke 40 with the positioning hole 35a provided in the protruding portion 34a of the elastic member 30a. Similarly, the yoke 40 and the elastic member 30b are aligned by aligning the alignment notch 44d provided in the protruding portion 43d of the yoke 40 with the positioning hole 35b provided in the protruding portion 34b of the elastic member 30b.

[0071] As shown in Figure 17, the protruding portion 43c of the yoke 40 and the protruding portion 34a of the elastic member 30a overlap each other in the region facing the curved portions 65a and 65b of the coils 61a and 61b. This is because at least a portion of the connecting portion 33a and the protruding portion 34a of the elastic member 30a are positioned in the region facing the curved portions 65a and 65b of the coils 61a and 61b. Also, although not shown in the figure, similarly, the protruding portion 43d of the yoke 40 and the protruding portion 34b of the elastic member 30b overlap each other in the region facing the curved portions 66a and 66b of the coils 61a and 61b. This is because at least a portion of the connecting portion 33b and the protruding portion 34b of the elastic member 30b are positioned in the region facing the curved portions 66a and 66b of the coils 61a and 61b.

[0072] Then, the protruding portion 43c of the yoke 40 is attached to the protruding portion 34a of the elastic member 30a by welding or the like, thereby fixing the elastic member 30a to the yoke 40. Also, the protruding portion 43d of the yoke 40 is attached to the protruding portion 34b of the elastic member 30b by welding or the like, thereby fixing the elastic member 30b to the yoke 40.

[0073] In this way, by fixing the elastic members 30a and 30b to the yoke 40 in the region opposite to the curved portions 65a, 65b, 66a, and 66b of the coils 61a and 61b, the region that does not affect the Lorentz force described later can be effectively utilized for fixing the elastic members 30a and 30b to the yoke 40.

[0074] (Operation of the vibration generator 1) The operation of the vibration generator 1, configured as described above, will be explained below.

[0075] First, let's explain the relationship between the magnet 50 and the coils 61a and 61b.

[0076] Figure 18 is a diagram showing the relationship between the magnet 50 and the coils 61a and 61b, and is a cross-sectional view taken along line A-A as shown in Figure 1.

[0077] As shown in Figure 18, the magnet 50 has upper magnetic pole portions 51aU, 51bU, 51cU, 51dU, 51eU, and 51fU on the upper side (Z1 side), and lower magnetic pole portions 51aD, 51bD, 51cD, 51dD, 51eD, and 51fD on the lower side (Z2 side). Furthermore, the upper pole portion 51aU and the lower pole portion 51aD have different polarities, the upper pole portion 51bU and the lower pole portion 51bD have different polarities, the upper pole portion 51cU and the lower pole portion 51cD have different polarities, the upper pole portion 51dU and the lower pole portion 51dD have different polarities, the upper pole portion 51eU and the lower pole portion 51eD have different polarities, and the upper pole portion 51fU and the lower pole portion 51fD have different polarities. For example, the upper pole portions 51aU, 51cU, 51eU and the lower pole portions 51bD, 51dD, 51fD are magnetized as north poles, and the upper pole portions 51bU, 51dU, 51fU and the lower pole portions 51aD, 51cD, 51eD are magnetized as south poles.

[0078] Furthermore, the bundled portion 63a of coil 61a faces the magnetic pole portion 51bD of magnet 50, the bundled portion 64a of coil 61a faces the magnetic pole portion 51cD of magnet 50, the bundled portion 63b of coil 61b faces the magnetic pole portion 51dD of magnet 50, and the bundled portion 64b of coil 61b faces the magnetic pole portion 51eD of magnet 50. In addition, the conductive member 62a faces the magnetic pole portions 51aD and 51bD of magnet 50, and the conductive member 62b faces the magnetic pole portions 51eD and 51fD of magnet 50.

[0079] In this state, for example, if the control unit 2 controls the coil 61a to flow current in the direction of arrow AR1 in Figure 11, current flows in the bundled portion 63a of the coil 61a toward the front of the paper (X1 direction). Since the bundled portion 63a is in a magnetic field where magnetic field lines MF1 are directed from Z1 to Z2, a force acts on the magnet 50 (lower magnetic pole portion 51bD) that tries to move it in the Y1 direction due to the reaction force of the Lorentz force. Also, current flows in the bundled portion 64a of the coil 61a toward the back of the paper (X2 direction). Since the bundled portion 64a is in a magnetic field where magnetic field lines MF2 are directed from Z2 to Z1, a force acts on the magnet 50 (lower magnetic pole portion 51cD) that tries to move it in the Y1 direction due to the reaction force of the Lorentz force. Furthermore, current flows in the bundled portion 63b of coil 61b in the direction towards the front of the paper (X1 direction), and since the bundled portion 63b is in a magnetic field where magnetic field lines MF1 are directed from Z1 to Z2, a force acts on the magnet 50 (lower magnetic pole portion 51dD) that tries to move it in the Y1 direction due to the reaction force of the Lorentz force. Also, current flows in the bundled portion 64b of coil 61b in the direction towards the back of the paper (X2 direction), and since the bundled portion 64b is in a magnetic field where magnetic field lines MF2 are directed from Z2 to Z1, a force acts on the magnet 50 (lower magnetic pole portion 51eD) that tries to move it in the Y1 direction due to the reaction force of the Lorentz force.

[0080] On the other hand, when the control unit 2 controls the coil 61a to flow current in the direction of arrow AR2 in Figure 11, current flows in the bundled portion 63a of the coil 61a toward the back of the paper (X2 direction). Since the bundled portion 63a is in a magnetic field where magnetic field lines MF1 are directed from Z1 to Z2, a force acts on the magnet 50 (lower magnetic pole portion 51bD) that tries to move it in the Y2 direction due to the reaction force of the Lorentz force. Also, current flows in the bundled portion 64a of the coil 61a toward the front of the paper (X1 direction). Since the bundled portion 64a is in a magnetic field where magnetic field lines MF2 are directed from Z2 to Z1, a force acts on the magnet 50 (lower magnetic pole portion 51cD) that tries to move it in the Y2 direction due to the reaction force of the Lorentz force. Furthermore, current flows in the bundled portion 63b of coil 61b in the direction towards the back of the paper (X2 direction), and since the bundled portion 63b is in a magnetic field where magnetic field lines MF1 are directed from Z1 to Z2, a force acts on the magnet 50 (lower magnetic pole portion 51dD) that tries to move it in the Y2 direction due to the reaction force of the Lorentz force. Also, current flows in the bundled portion 64b of coil 61b in the direction towards the front of the paper (X1 direction), and since the bundled portion 64b is in a magnetic field where magnetic field lines MF2 are directed from Z2 to Z1, a force acts on the magnet 50 (lower magnetic pole portion 51eD) that tries to move it in the Y2 direction due to the reaction force of the Lorentz force.

[0081] Next, we will explain the operation of the vibration generator 1 when the above-described effects occur.

[0082] Figures 19 to 21 are diagrams illustrating the operation of the vibration generator 1, and are viewed from the Z1 direction. In Figures 19 to 21, the upper case 10 is removed to make the operation of the vibration generator 1 easier to understand, but only the inner surfaces of the side walls 13a and 13b of the upper case 10 are shown.

[0083] When no current flows through the coils 61a and 61b under the control of the control unit 2, the Lorentz force described above is not generated. As shown in Figure 19, the elastic arms 31a and 32a of the elastic member 30a and the elastic arms 31b and 32b of the elastic member 30b are not elastically deformed, and the yoke 40 (and magnet 50) is located in the central part of the vibration generator 1 in the Y-axis direction.

[0084] From this state, when the control unit 2 controls the coils 61a and 61b to flow current in the direction of arrow AR1 in Figure 11, a force acts on the magnet 50 that attempts to move it in the Y1 direction due to the reaction force of the Lorentz force described above.

[0085] The yoke 40, attracted to the magnet 50, is attached to the elastic member 30a by an overhang 43c and to the elastic member 30b by an overhang 43d. The elastic member 30a is fixed to the side walls 13a and 13b of the upper case 10 by welding or the like at the fixing parts 36a and 37a, and the elastic member 30b is fixed to the side walls 13a and 13b of the upper case 10 by welding or the like at the fixing parts 36b and 37b. The elastic arms 31a, 31b, 32a, and 32b elastically deform, allowing the yoke 40, which is attached to the overhang parts 34a and 34b by welding or the like, to vibrate in the Y-axis direction together with the magnet 50.

[0086] Therefore, when a force acts on the magnet 50 that attempts to move it in the Y1 direction due to the reaction force of the Lorentz force described above, as shown in Figure 20, in the elastic member 30a, the elastic arm 31a elastically deforms so that it contracts in the Y-axis direction, and the elastic arm 32a elastically deforms so that it extends in the Y-axis direction. In the elastic member 30b, the elastic arm 31b elastically deforms so that it contracts in the Y-axis direction, and the elastic arm 32b elastically deforms so that it extends in the Y-axis direction.

[0087] As a result, the yoke 40 moves together with the magnet 50 in the direction D1 in Figure 20.

[0088] Furthermore, when the control unit 2 controls the coils 61a and 61b to flow current in the direction of arrow AR2 in Figure 11, a force acts on the magnet 50 that attempts to move it in the Y2 direction due to the reaction force of the Lorentz force described above.

[0089] Then, when a force acts on the magnet 50 that attempts to move it in the Y2 direction due to the reaction force of the Lorentz force described above, as shown in Figure 21, in the elastic member 30a, the elastic arm 31a elastically deforms so that it extends in the Y-axis direction, and the elastic arm 32a elastically deforms so that it contracts in the Y-axis direction. In the elastic member 30b, the elastic arm 31b elastically deforms so that it extends in the Y-axis direction, and the elastic arm 32b elastically deforms so that it contracts in the Y-axis direction.

[0090] As a result, the yoke 40 moves together with the magnet 50 in the direction D2 in Figure 21.

[0091] The control unit 2 can, for example, repeatedly reverse the direction of the current flowing through the coils 61a and 61b at a predetermined period (for example, by flowing a sinusoidal current or a square wave current), thereby alternately generating the state shown in Figure 20 and the state shown in Figure 21, with the state shown in Figure 19 in between. The predetermined period is, for example, the period corresponding to the natural frequency corresponding to the mass of the movable body MB and the spring constant of the elastic member 30.

[0092] Specifically, when the vibration generator 1 reaches the state shown in Figure 20, the control unit 2 reduces or stops the supply of current to the coils 61a and 61b. When the current to the coils 61a and 61b becomes zero, the Lorentz force and its reaction force disappear. At this time, the movable body MB, consisting of the yoke 40 and the magnet 50, is pushed back in the Y2 direction by the restoring force of the elastic member 30, and after a predetermined time has elapsed, it reaches the state shown in Figure 19. The same applies when the vibration generator 1 reaches the state shown in Figure 21.

[0093] In this way, the vibration generating device 1 in this embodiment generates vibration by the movable body MB reciprocating in the Y-axis direction within the housing HS.

[0094] Furthermore, in order for the elastic arms 31a, 32a, 31b, and 32b of the elastic member 30 to undergo elastic deformation as described above, it is preferable that they be positioned such that there is a small gap between them and the upper surface of the lower case 20 and the lower surface of the frame portion 11 of the upper case 10. Moreover, considering that the elastic member 30 will wobble in the Z-axis direction when it undergoes elastic deformation, it is preferable that the distance between it and the upper surface of the lower case 20 and the distance between it and the lower surface of the frame portion 11 of the upper case 10 are equal.

[0095] Furthermore, in order to improve the properties of the elastic member 30 through elastic deformation, it is preferable that the elastic member 30 has a wide width in the Z-axis direction. On the other hand, as described above, even if an unexpected impact such as a fall is applied, the elastic member 30 will not move significantly in the Y-axis direction. Therefore, even if the width of the elastic member 30 in the Z-axis direction is widened and the coil body 60 and the elastic member 30 overlap in the Z-axis direction, the elastic member 30 will not move in the Y-axis direction and come into contact with the conductive member 62 and the coil body 60 and cause damage when an unexpected impact such as a fall is applied. This makes it possible to widen the width of the elastic member 30 in the Z-axis direction and improve the properties through elastic deformation.

[0096] This application claims priority under Japanese Patent Application No. 2024-230268, filed on 26 December 2024, the entire contents of which are incorporated herein by reference.

[0097] 1 Vibration Generator 2 Control Unit 10 Upper Case 11 Frame Section 11a-11d Inner Edge Section 12a, 12b, 42a-42d Protruding Section 13a-13d Side Wall Section 14 Opening 15 Opening 16a-16d Bottom Wall Section 20 Lower Case 21, 41 Flat Plate Section 22 Hole Section 30, 30a, 30b Elastic Member 31a, 31b, 32a, 32b Elastic Arm Section 33a, 33b Connecting Section 34a, 34b, 43c, 43d Overhanging Section 35a, 35b Positioning Hole 36a, 36b, 37a, 37b Fixing Section 40 Yoke 41a-41d Outer Edge Section 44c, 44d Positioning Notch 50 Magnet 51a-51f Magnetic pole section 60 Coil body 61a, 61b Coil 62, 62a, 62b Conductive member 63a, 63b, 64a, 64b Wire bundle section 65a, 65b, 66a, 66b Curved section 80 Connecting member 81 Substrate 82a, 82b, 83a-83d Terminal HS Housing MB Movable body

Claims

1. A vibration generating device comprising: a housing comprising a lower case on which a coil is mounted and an upper case; a magnet and a yoke disposed above the magnet, a movable body disposed above the coil and opposite to the coil, and vibrating in a first direction relative to the housing; and a pair of elastic arms disposed on both sides of the movable body in the first direction, and connected to the housing and the movable body on the upper side of the lower case, wherein the upper case exposes the movable body in its central part and has a frame that covers the pair of elastic arms.

2. The vibration generating device according to claim 1, wherein the height of the upper surface of the frame is the same as the height of the upper surface of the movable body.

3. The vibration generating device according to claim 1, wherein the upper case has a first projection that protrudes downward from each of the two inner edges of the frame portion that are opposite to each other in the first direction, and the yoke has a second projection that protrudes downward from its outer edge and is opposite to the first projection.

4. The vibration generating device according to claim 3, wherein the first protrusion is positioned in a region that does not overlap with the elastic arm when the movable body moves in the first direction.

5. The vibration generating device according to claim 4, wherein two sets of the pair of elastic arms are provided in a second direction perpendicular to the first direction, the first projection is provided in the center of the upper case in a second direction perpendicular to the first direction of the frame, and different sets of the elastic arms are arranged on each side of the first projection in the second direction.

6. The vibration generating device according to claim 5, wherein an elastic member is formed by providing a connecting portion that connects the pair of elastic arms.

7. The vibration generating device according to claim 6, wherein the yoke has a first protruding portion extending from the magnet, and the elastic member has a connecting portion attached to the first protruding portion.

8. The vibration generating device according to claim 7, wherein the coil has a plurality of bundled portions extending in the second direction and a curved portion connecting the plurality of bundled portions, and at least a portion of the connecting portion and the first overhang portion is arranged to face the curved portion in the vertical direction.

9. The vibration generating device according to claim 8, wherein the connecting portion has a second protruding portion opposite to the first protruding portion, and the elastic member is fixed to the yoke by the second protruding portion being attached to the first protruding portion.

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