Abstract:
A bell that rings when the entire rolling element bell is shaken, includes a base section having a recess, and a bell section that is supported directly or indirectly by the base section, a rolling element that is adapted to roll in the recess, the rolling element hitting the base section when the entire rolling element bell has been shaken, and the rolling element has rolled to reach an edge of the recess of the base section, and the rolling element bell being configured so that sound produced by the rolling element bell is adjusted by adjusting a contact angle or a contact height of the rolling element with an inner wall of the bell section.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Patent Application No. PCT/JP2012/76647, having an international filing date of Oct. 15, 2012, which designated the United States and which claims priority from Japanese Patent Application No. 2011-281711 filed on Dec. 22, 2011, Japanese Patent Application No. 2012-021987 filed on Feb. 3, 2012, and Japanese Patent Application No. 2012-078271 filed on Mar. 29, 2012, the entirety of each of the above international and Japanese applications being incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a highly resonant bell that may be used in various fields such as a doorbell, an alarm bell, an animal repeller bell, and a call bell. 
     2. Description of the Related Art 
     Various bells such as a doorbell that is rung by a visitor, an alarm bell that gives a warning, an animal repeller bell (e.g., bear repeller bell), and a good luck bell have been proposed. These bells may not ring when shaken to only a small extent, and may produce a monotonous sound. 
     Patent Japanese Utility Model Registration No. 3012065 discloses a bell in which a rolling element is placed in a space surrounded by a metal sheet, and Patent Japanese Design Registration No. 392367 discloses a toy bell in which a ball is held between upper and lower resonators. However, these bells may not ring when shaken to only a small extent. 
     As illustrated in  FIG. 15 , a related-art bell may have a structure in which a weight  114  is suspended using a suspension member  111  (e.g., string) inside a bell section  112 , for example. 
     Such a structure has a problem in that the swing cycle of the weight  114  is determined by the length of the suspension member  111 . 
     When a bell has a structure in which a ball is suspended, the ball hits the inner wall of the bell section at a constant angle. 
     Since the ball is suspended using a string or the like, the bell does not ring immediately when the bell section has been shaken. 
     SUMMARY 
     An object of the invention is to provide a bell that rings even when shaken to only a small extent, and allows an easy adjustment of loudness and tone. 
     According to one aspect of the invention, there is provided a rolling element bell that rings when the entire rolling element bell is shaken, the rolling element bell including:
     a base section having a recess;   a bell section that is supported directly or indirectly by the base section; and   a rolling element that is adapted to roll in the recess,   the rolling element hitting the base section when the entire rolling element bell has been shaken, and the rolling element has rolled to reach an edge of the recess of the base section, and   the rolling element bell being configured so that sound produced by the rolling element bell is adjusted by adjusting a contact angle or a contact height of the rolling element with an inner wall of the bell section.   

     The term “rolling element” used herein refers to an element that rolls and hits the bell section when the entire bell is shaken or moved. The expression “rolls to reach the edge of the recess” means that the rolling element rolls and hits the bell section. 
     The shape of the rolling element is not limited as long as the rolling element rolls. It is preferable that the rolling element have a ball-like shape (spherical shape) so that the rolling element easily rolls. 
     It is preferable to connect the base section and the bell section so that a given opening or space is formed. This makes it possible to improve resonance. 
     In the rolling element bell according to one aspect of the invention, the rolling cycle (speed) of the rolling element (e.g., ball) is adjusted by adjusting the shape of the bottom of the recess of the base section (i.e., the shape of the rolling contact surface). 
     Specifically, a known bell has a problem in that it is difficult to adjust sound due to the effects of the length of the suspension member. In contrast, the bell according to one aspect of the invention makes it possible to easily adjust sound by adjusting the curvature of the bottom of the recess, for example. 
     Since the bell according to one aspect of the invention is configured so that the rolling element (e.g., ball) rolls on the rolling contact surface that is formed on the base section and has a recess shape, the degree of ease of rolling and the rolling speed of the rolling element can be adjusted by adjusting the shape of the rolling contact surface. 
     When the rolling contact surface has a spherical surface shape in which the center is situated at the lowest position, and the curvature radius of the spherical surface is reduced, the rolling element less strongly hits the bell section, so that a small sound is produced. 
     When the bell is shaken to only a small extent, the rolling element returns to the center of the rolling contact surface before the rolling element hits the bell section (i.e., sound is not produced). 
     When the curvature radius of the rolling contact surface is increased so that the rolling contact surface is almost flat, sound is produced even when the bell is shaken to only a small extent. 
     The rolling contact surface need not necessarily have a spherical surface shape. The rolling contact surface may have a groove that restricts the rolling direction of the rolling element. For example, a groove may be formed radially from the center to the periphery, or may be formed spirally. 
     When the bottom of the recess has a spherical surface area having a given curvature at least at the center thereof, the rolling cycle of the rolling element and the hitting strength when the rolling element hits the bell section can be easily adjust by utilizing the spherical surface area. 
     When a related-art bell has a configuration in which a ball is suspended using a string or the like, the ball hits the inner wall of the bell section at a constant angle. In contrast, the bell according to one aspect of the invention is configured so that the rolling element hits the inner wall of the bell section in a different way depending on the tilt angle of the rolling contact surface of the base section and the angle of the inner wall of the bell section. Therefore, the tilt angle of the rolling contact surface of the base section, the angle of the inner wall of the bell section, and the contact height of the rolling element may be adjusted. 
     The bell section also rings in a different way depending on the size and the material of the rolling element. The bell according to one aspect of the invention allows easy replacement of the rolling element. 
     The base section may include a stop section that stops the rolling element when the amount of shake or vibration applied to the bell is equal to or less than a given amount. 
     The stop section that stops the rolling element may be implemented by forming a small depression in the recess (e.g., the center of the recess) of the base section, or embedding a magnet in the base section, or disposing a magnet on the back side of the base section when the base section is not formed of a ferromagnetic material (e.g., iron), and the rolling element is formed of a magnetic material. 
     Note that the stop section is not limited as long as the stop section prevents movement of the rolling element when the amount of shake or vibration applied to the bell is small. 
     According to the above configuration, the rolling element does not move when the bell is shaken to only a small extent, but moves out from the depression, or moves away from the magnet, and hits the resonator when the amount of shake applied to the bell has become equal to or larger than the given amount. 
     The base section may be supported by an elastic body. Alternatively, in addition to that the base section may be supported by an elastic body, the swing cycle of the base section may be adjusted by adjusting the modulus of elasticity of the elastic body, for example. 
     The bell according to one aspect of the invention may be used alone. 
     The bell according to one aspect of the invention may be incorporated in an arbitrary product, or may be attached to an attachment target such as a door. 
     When the bell is attached to a door or the like, the bell may be attached to the outer side of a door or the like, or may be attached to the inner side of a door or the like. 
     A front door may be a hinged door that rotates in the forward/backward direction, or a sliding door that slides in the transverse direction. A sliding door shakes to only a small extent as compared with a hinged door. 
     Since the bell according to one aspect of the invention is configured so that the rolling element rolls on the upper side of the base section, and hits the bell section, a large sound is produced even when the bell is attached to a sliding door that shakes to only a small extent. 
     The bell according to one aspect of the invention can be configured not to ring when the amount of shake is small (e.g., shake due to wind). 
     When an attachment section for attaching the bell to the attachment target is connected to the bell via an elastic body, the amount of shake of the bell is amplified or reduced by the elastic body. 
     For example, when the bell is provided upright on the attachment section through the elastic body, the amount of shake of the attachment section is amplified by the elastic body. When the bell is suspended under the attachment section using the elastic body, the amount of shake of the attachment section is reduced by the elastic body. 
     The bell rings for a long time when the bell is connected to the elastic body. 
     When the bell according to one aspect of the invention is attached to a door, the bell may be attached to a knob for opening and closing the door. 
     When the bell includes a control section that controls the moving range of the rolling element on the base section, or stops the movement of the rolling element, it is possible to control the shake strength and loudness, or prevent production of sound. 
     The bell according to one aspect of the invention is configured so that the pitch, intensity, tone, and the like of sound produced can be adjusted by adjusting the way in which the rolling element hits the bell section. 
     In particular, the rolling cycle and the rolling speed of the rolling element can be easily adjusted by adjusting the curvature of the bottom, or providing a groove that restricts the rolling path, for example. 
     When the curvature radius of the rolling contact surface is increased so that the rolling contact surface is almost flat, sufficient kinetic energy can be applied even if the amount of shake is small, so that a large sound can be produced. 
     The loudness and the tone of sound can be easily adjusted by adjusting the modulus of elasticity of the elastic body that supports the base section. 
     When the control section that controls the rolling element is provided, it is possible to control the moving (rolling) range of the rolling element, or stop the rolling element. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a cross-sectional view illustrating an example of a bell according to one embodiment of the invention bell, and  FIG. 1B  is a partial enlarged view illustrating a state in which rolling element hits a bell section. 
         FIGS. 2A to 2C  illustrate the measurement results for the relationship between the curvature of a rolling contact surface and sound pressure, wherein the curvature radius R is 70 mm in  FIG. 2A , 80 mm in  FIG. 2B , and 90 mm in  FIG. 2C . 
         FIGS. 3A to 3C  illustrate the measurement results for the relationship between the curvature of a rolling contact surface and sound pressure, wherein the curvature radius R is 100 mm in  FIG. 3A , 150 mm in  FIG. 3B , and 200 mm in  FIG. 3C . 
         FIGS. 4A to 4C  illustrate an example of the structure of bell according to one embodiment of the invention (i.e., an example of a resonator (bell section) in the shape of a hanging bell), wherein the curvature of a recessed side of a base section is changed. 
         FIGS. 5A and 5B  illustrate examples of the shape of a recessed side of a base section, wherein a depression is formed in  FIG. 5A , and a magnet is attached to the back side in  FIG. 5B . 
         FIG. 6  illustrates an example in which a base section is supported by an elastic body. 
         FIG. 7  illustrates an example in which a bell is incorporated in a product. 
         FIGS. 8A to 8C  illustrate connection examples of a base section and a bell section, wherein  FIG. 8A  illustrates an example in which the base section is connected to the upper end of the bell section,  FIG. 8B  illustrates an example in which the base section and the bell section are connected via a post provided inside the bell section, and  FIG. 8C  illustrates an example in which the base section and the bell section are connected via a post that is branched in the shape of the letter “U”. 
         FIGS. 9A and 9B  illustrate examples in which an attachment section and a bell are connected via an elastic body, wherein  FIG. 9A  illustrates an example in which a base section is connected to the attachment section, and  FIG. 9B  illustrates an example in which a bell section is connected to the attachment section. 
         FIGS. 10A and 10B  illustrate examples in which a bell is attached to a knob of a door, wherein  FIG. 10A  illustrates an example in which the bell is attached to the upper part of the knob, and  FIG. 10B  illustrates an example in which the bell is attached to the lower part of the knob. 
         FIGS. 11A and 11B  illustrate examples in which a base section is provided inside a bell section. 
         FIGS. 12A and 12B  illustrate an example in which a base section is provided inside a bell section, and the movement of a rolling element is controlled by utilizing a lid. 
         FIG. 13  illustrates an example in which a cover member is attached to a bell section, and a rolling contact surface formed at the bottom of the cover member. 
         FIG. 14  illustrates an example in which a control section that controls the rolling motion of a rolling element is provided inside a bell section provided with a cover. 
         FIG. 15  illustrates an example of the structure of a related-art bell. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       FIG. 1A  illustrates an example of the cross-sectional structure of a bell  10  according to one embodiment of the invention. As illustrated in  FIG. 1A , the bell  10  includes a base section  11  and a bell section  12 . A rolling element  20  having a spherical shape or the like is placed on a rolling contact surface  11   a  that is formed on the upper side of the base section  11 , and has a recessed shape. 
     The bell section  12  is connected to and supported by the base section  11 . An arbitrary support structure may be employed (not illustrated in  FIG. 1 ). 
     The bell section  12  may be connected to the base section in an area inside the bell section  12 , or may be connected to the base section in an area outside the bell section  12 . 
     An opening  13  is formed between the base section  11  and the bell section  12  so that resonance easily occurs. 
     The relationship between the curvature radius R of the rolling contact surface having a spherical surface shape and the sound pressure is described below. 
     The bell section  12  is formed of brass. The bell section  12  is formed in the shape of a hanging bell, and has an outer diameter φ 1  of 54 mm, a lower end outer diameter φ 2  of 48 mm, and a height H of 34.5 mm. 
     The base section  11  has an upper surface outer diameter φ 3  of  47  mm, and the opening  13  has a horizontal dimension of 0.5 mm. 
     An iron ball having a diameter of 11 mm and a weight of 5 g is used as the rolling element  20 . 
     The curvature radius R of the rolling contact surface  11   a  is set to 70, 80, 90, 100, 150, or 200 mm. The bell is horizontally moved by about 100 mm at a speed of 30,000 mm/min. A sound pressure measurement microphone is disposed at a position away from the target position of the bell by 100 mm. 
       FIGS. 2A to 2C  and  3 A to  3 C show the sound pressures (Pa) thus measured. 
     The sound pressures (Pa) shown in  FIGS. 2A to 2C  and  3 A to  3 C are compared below. 
     The rolling element (iron ball) rolled in the direction opposite to the moving direction of the bell, hit the inner wall of the bell section, rolled in the opposite direction, and hit the inner wall of the bell section again. 
     The first hitting sound decreased, and the second hitting sound increased as the curvature radius R decreased. The second sound pressure when the rolling element rolled in the swing direction and hit the bell section tended to decrease as the curvature radius R decreased. 
     The rolling element  20  more easily rolled, and the sound pressure increased as the curvature radius R increased. 
     It was confirmed by the above experimental results that the sound pressure can be adjusted by changing the shape of the rolling contact surface of the base section  11 . 
     The sound pressure also changes depending on the hitting direction of the rolling element, and the contact angle θ and the contact height with the inner wall of the bell section  12  (see  FIG. 1B ). 
     Therefore, the sound pressure can also be adjusted by adjusting the tilt angle of the rolling contact surface of the base section  11  and the upright angle of the inner wall of the bell section  12 . It is preferable to adjust the height so that sound is more easily produced. 
     An example in which the base section and the bell section are connected using a connection section  14  is described below. 
       FIGS. 4A to 4C  are cross-sectional views illustrating an example in which the bell section  12  is in the shape of a hanging bell, and the base section  11  is in the shape of a disc. 
     Note that the bell section  12  and the base section  11  may have an arbitrary shape. 
     In  FIG. 4A , the base section  11  has a recessed upper side having a large curvature radius so that the rolling element  20  easily rolls even when the bell  10  is moved to only a small extent. 
     The base section  11  may be formed of an arbitrary material (e.g., metal, resin, or wood) as long as the base section  11  can hold the rolling element  20  so that the rolling element  20  rolls. 
     The recessed side of the base section  11  on which the rolling element  20  rolls is preferably formed using a rubber sheet or a resin material so that noise does not occur when the rolling element rolls. 
     It is preferable that the bell section  12  be formed of a metal. 
     The rolling element  20  may be formed of an arbitrary material as long as the rolling element  20  can produce sound when the rolling element  20  hits the bell section  12 . 
     A rolling element formed of wood, a resin, or a metal may be selectively used depending on the desired tone and loudness. 
     The rolling element  20  may have a shape other than a spherical shape (ball-like shape) as long as the rolling element  20  easily rolls. 
     The shape of the recessed side of the base section  11  may be appropriately set taking account of the size of the rolling element  20  and the duration of sound. 
     The curvature radius of the recessed side is reduced in order from  FIG. 4A ,  FIG. 4B , and  FIG. 4C . 
     The cycle of the rolling motion of the rolling element can be adjusted by merely changing the curvature of the recessed side. 
       FIGS. 5A and 5B  illustrate an example in which a stop section that stops the rolling element is provided to the base section. 
       FIG. 5A  illustrates an example in which a small depression  21  is formed almost at the center of the rolling contact surface (recessed side) of the base section  11 . 
     In this case, the rolling element  20  is held by the depression  21  (i.e., sound is not produced) when the bell  10  is moved or shaken to only a small extent, but sound is produced when the bell  10  is moved or shaken to such an extent that the rolling element  20  leaves the depression  21 . 
       FIG. 5B  illustrates an example in which the base section is formed of a material other than a ferromagnetic material, the rolling element is formed of a magnetic material (e.g., iron ball), and a magnet  22  is disposed on the base section. 
     In this case, the rolling element is stopped due to the magnetism of the magnet when the bell  10  is moved or shaken to only a small extent. In  FIG. 5B , an arm  16  for attaching the bell  10  to a door or the like is also provided. 
       FIG. 6  illustrates an example in which the base section  11  is supported by a support member  23  that is formed using an elastic body. 
     The base section having a shape as illustrated in  FIG. 1  may be supported by an elastic body that is provided separately. In  FIG. 6 , a bell section  12   a  is disposed upside down, and the base section  11  is elastically supported inside the bell section  12   a.    
     In this case, the base section  11  shakes or swings due to the support member  23 . 
     Therefore, the base section  11  shakes and hits the bell section  12   a . In this case, the rolling element  20  need not necessarily be provided. 
     When the rolling element  20  is disposed on the base section supported by the support member  23  (see  FIG. 6 ), sound may be produced by the rolling element  20  when the bell  10  is shaken to only a small extent, and the base section  11  may hit the bell section  12   a  to produce sound. 
     The degree of shake that may occur when the bell  10  is shaken can be adjusted by adjusting the modulus of elasticity of the elastic body. 
     In this case, the support member  23  that supports the base section  11  may be formed using a rigid body, or may be formed using a flexible elastic body. 
     A lid or the like may be provided so that the rolling element  20  does not fall off from the base section  11 . 
       FIG. 7  is an example in which the bell according to one embodiment of the invention is incorporated in a product  30  that has a suspension section  31 . 
     The bell according to one embodiment of the invention may be incorporated in various products in this manner instead of attaching the bell to a door or the like. 
     The base section  11  and the bell section  12  may be connected using either one of the connection section  14  shown in  FIGS. 4 and 7 , or the base section  11  and the upper end of the bell section  12  may be connected using a connection section  14   a  shown in  FIG. 8A . The connection position is not particularly limited. 
       FIG. 8B  illustrates an example in which the base section  11  and the bell section  12  are connected using a post connection section  14   b  that is provided inside the bell section  12 , and 
       FIG. 8C  illustrates an example of a post connection section  14   c  that is branched in the shape of the letter “U”. 
     The bell may be used alone, or may be attached to the attachment target using an attachment section  16  (see  FIG. 5B ). 
     The connection section may removably connect the base section  11  and the bell section  12  so that the rolling element  20  can be easily placed in the bell, or can be easily replaced. The connection section may be integrally formed with the base section  11  and/or the bell section  12 . 
     The connection section may be formed using an elastic body, or the connection section may include an elastic material. 
     As illustrated in  FIG. 9A , the amount of shake of the bell  10  is amplified by providing an elastic body  17  such as a spring between the base section  11  and the attachment section  16 . 
     As illustrated in  FIG. 9B , the amount of shake of the bell is reduced as compared with the amount of shake of the attachment section  16  by connecting the bell  10  to the attachment section  16  so that the bell  10  is suspended from the elastic body  17 . 
     In this case, the bell  10  shakes for a longer time. 
       FIGS. 10A and 10B  illustrate an example in which the bell  10  is attached to a knob  21  of a sliding door  2 . 
       FIG. 10A  illustrates an example in which the bell  10  is attached to the upper side of the knob  21 , and  FIG. 10B  illustrates an example in which the bell  10  is suspended from the lower side of the knob  21 . 
     Therefore, the motion of the knob  21  is transmitted directly to the bell  10 . 
     Note that the bell  10  according to one embodiment of the invention is not limited to a structure in which the bell section  12  is provided to cover the base section  11 . As illustrated in  FIG. 11A , a base section  11   d  may be provided in a bell section  12   b . As illustrated in  FIG. 11B , a base section  11   e  may be provided in a space formed by two bell sections  12   c  and  12   d  that are disposed opposite to each other. 
       FIGS. 12A and 12B  illustrate an example in which a mechanical control section is provided as a control section that controls the rolling motion of the rolling element  20 . 
     When the rolling element is formed using a magnetic material, the rolling element may be stopped internally or externally by utilizing magnetism. 
       FIGS. 12A and 12B  are cross-sectional end views that illustrate a hollow columnar appearance. 
     In  FIGS. 12A and 12B , a bell section  12   e  and a base section  11  are disposed inside a case  31  having a bottomed cylindrical shape. 
     The case  31 , the bell section  12   e , and the base section  11  may be connected by a method other than the above method. In  FIGS. 12A and 12B , an internal thread section  31   a  is formed at the bottom of the case  31 , and an external thread section is formed at the end of a post  11   f  of the base section  11 . The external thread section is screwed into the internal thread section  31   a  to secure the bell section  12   e.    
     An internal thread section  31   b  is formed around the opening of the case  31 , and an external thread section  32   a  of the lid (control section)  32  is screwed into the internal thread section  31   b  to close the opening of the case  31 . 
     In this case, the rolling element  20  can be held and stopped by an inner side  32   c  of the lid  32  by tightening the lid  32  (see  FIGS. 12A and 12B ). 
     When the inner side of the lid  32  has a recessed shape so that an edge  32   b  of the inner side of the lid  32  protrudes downward, the way in which the rolling element  20  hits the bell section  12   e  can be changed by adjusting the dimension d of the opening between the edge  32   b  and an edge  11   g  of the recessed side of the base section  11 . 
     For example, when the dimension d is larger than the diameter of the rolling element  20 , the rolling element  20  hits the bell section  12   e  even when the bell is shaken to only a small extent. When the dimension d is smaller than the diameter of the rolling element  20  to some extent, sound is not produced unless the bell is shaken strongly. 
     When the lid  32  (control section) is transparent, the movement of the rolling element can be observed from the outside. 
     The rolling element  20  rolls and produce sound even when the bell is disposed upside down, or laid down. 
     The levelness of the bell may be determined by utilizing the rolling motion of the rolling element  20 . 
       FIG. 13  illustrates an example of a bell provided with a cover. 
     The bell section  12  is formed in the shape of a hanging bell, and provided with a handle section  15  on the upper side. 
     A cover member  40  is provided from the handle section  15  to cover the bell section  12 . 
     The bottom of the cover member  40  is used as the base section  11  in order to form the rolling contact surface  11   a  at the bottom of the cover member  40 . 
     The rolling element  20  is placed on the rolling contact surface  11   a  formed at the bottom of the cover member  40 . The rolling element  20  rolls when the bell is shaken, and sound is produced when the rolling element  20  hits the bell section  12 . 
     The base section  11  and the handle section of the bell section are connected using the connection section  14  on the upper side of the cover member. 
       FIG. 14  illustrates an example in which a control section  32  that controls the rolling motion of the rolling element  20  is further provided inside the bell section  12 . 
     The control section  32  has a configuration in which an external thread section  31   a  formed on the handle section is screwed into an internal thread section  32   a  formed in the upper area of the bell section  12 . 
     The outer side of the bottom of the cover member may have a convex shape so that the bell swings back and forth and around for a long time. 
     The bell according to one embodiment of the invention may include a mechanical level mechanism (e.g., space top) that holds the bell horizontally, a float mechanism that allows the bell to float on water, or a gravitational level mechanism. 
     The rolling element bell according to the embodiments of the invention may be widely used as a doorbell, a call bell, and the like. 
     Although only some embodiments of the present invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within scope of this invention. In addition, it should be understood that aspects of the preferred embodiment(s) generally may be interchanged in whole or in part.