Patent Publication Number: US-2011057888-A1

Title: Touch screen device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Korean Patent Application No. 10-2009-0085058, filed Sep. 9, 2009, entitled “Touch Screen Device”, which is hereby incorporated by reference in its entirety into this application. 
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a touch screen device. 
     2. Description of the Related Art 
     Recently, according to requirements of consumers to enhance the convenience of using electronic products, there are an increasing number of electronic products using touch screens which allow a signal to be input in a manner wherein the presence and location of touching within a display area is detected. Touch screen devices not only include the concept of inputting a signal by touching but also include the concept of incorporating the intuitive experience of a user into an interface and of diversifying feedback. 
     Touch screen devices have many advantages because the size of a device can be reduced, it can be easily and simply manipulated, the specifications thereof can be easily changed, a user can easily recognize information, and it is compatible with other IT devices. Because of these advantages, touch screen devices are widely used in various fields including industry, traffic, services, medical care, mobile products, etc. 
     As shown in  FIG. 8 , in a touch screen device  10  according to a conventional technique, a touch screen panel  11 , an image display  12 , a circuit board and a support casing  14  are coupled to each other by double-sided adhesive tape  13 . 
     However, the double-sided adhesive tape  13  which couples the elements to each other interferes with the vibrating operation of the touch screen device  10 . Thus, it is required to increase the capacity of a vibration unit to increase the vibrational force of the device. This increases the production cost of the touch screen device  10  and deteriorates the degree of freedom of installation space in the touch screen device  10 . 
     Furthermore, as can be understood in [Equation 1], a vibrational force G is in to inverse proportion to a total mass M. That is, if the total mass M reduces, the vibrational force G increases. If a partial mass m which is the mass of a vibrating element increases or a vibrational displacement x of the vibrating element increases, the vibrational force G increases. 
         G= ( −m·x·w   2 )/ M   [Equation 1]
 
     Therefore, based on [Equation 1], a touch screen device which is constructed such that the vibrational force G thereof can be increased by controlling the total mass, the partial mass and the vibrational displacement of the touch screen device, and abrasion between elements thereof can be prevented is required. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in an effort to provide a touch screen device which can increase the vibrational force and prevent abrasion between elements. 
     In a touch screen device according to an embodiment of the present invention, a touch screen panel receives an external input signal. An image display is provided under the touch screen panel. The image display converts an electric signal into an image signal. A rigid body which vibrates is provided under the image display. A first connector connects the image display to the rigid body. A vibration unit is mounted to the rigid body to generate vibrations. A weight is mounted to the rigid body to increase a mass of the rigid body. An elastic member is mounted to the rigid body to increase a vibrational displacement of the rigid body. A lower support is provided under the rigid body. A second connector connects the rigid body to the lower support. A third connector connects the touch screen panel to the lower support. 
     The touch screen panel may be integrated with the image display. 
     The vibration unit may comprise a piezoelectric or polymer actuator or motor. 
     The weight may be made of material having a high density. 
     The elastic member may comprise a coil spring or a plate spring increasing the vibrational displacement of the rigid body when the rigid body vibrates in a vertical direction. 
     The elastic member may be integrally formed at a predetermined position in the rigid body. 
     Each of the first connector, the second connector and the third connector may comprises elastic material for absorbing external vibration and impact. 
     Furthermore, a vibration frequency of the rigid body may be changed depending on a shape of the elastic member. 
     In a touch screen device according to the present invention, a total mass of a part which is vibrated by a vibrating element is reduced. A partial mass that is the mass of a rigid body which vibrates using a vibration unit is increased. A vibrational displacement of the rigid body which vibrates along with the vibration unit is increased. Therefore, the vibrational force of the device can be maximized. 
     Furthermore, it is unnecessary to increase the size of the vibration unit which is made of expensive material, to increase the vibrational force. In other words, the present invention can reduce the size of the vibration unit, thus reducing the production cost of the touch screen device. 
     In addition, because the vibration unit is fastened to the rigid body, the vibration unit can be prevented from being damaged, for example, by falling. Thus, the strength of the touch screen device can be improved. As well, the modularization of the rigid body, the vibration unit and the first connector can be realized. 
     Moreover, the frequency of the rigid body can be changed depending on the shape of the elastic members or elastic portions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a schematic sectional view illustrating a touch screen device, according to an embodiment of the present invention; 
         FIG. 2  is a view showing a weight and a vibration unit which are mounted to a rigid body of the touch screen device according to the present invention; 
         FIG. 3  is a view showing elastic members mounted to the rigid body of the touch screen device according to the present invention; 
         FIG. 4  is an enlarged view of the rigid body of the touch screen device according to the present invention; 
         FIG. 5  illustrates another embodiment of elastic members mounted to the touch screen device according to the present invention; 
         FIG. 6  is a side view of the rigid body according to the present invention; 
         FIG. 7  illustrates another embodiment of elastic members mounted to the touch screen device according to the present invention; and 
         FIG. 8  is a sectional perspective view of a touch screen device according to a conventional technique. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference now should be made to the drawings, in which the same reference numerals are used throughout the different drawings to designate the same or similar components. In the following description, when it is determined that the detailed description of the conventional function and conventional structure would confuse the gist of the present invention, such a description may be omitted. Furthermore, the terms and words used in the specification and claims are not necessarily limited to typical or dictionary meanings, but must be understood to indicate concepts selected by the inventor as the best method of illustrating the present invention, and must be interpreted as having had their meanings and concepts adapted to the scope and sprit of the present invention so that the technology of the present invention could be better understood. 
     Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings. 
       FIGS. 1 through 7  illustrate a touch screen device  100  according to the embodiment of the present invention. The touch screen device  100  includes a touch screen panel  110 , an image display  120 , a rigid body  130  and a lower support  140 . 
     The touch screen device  110  according to the present invention is configured as to maximize the vibrational force. As illustrated in Equation 1 pertaining to the vibrational force, the vibrational force G of the touch screen device  100  can be increased by reducing a total mass M of the touch screen device  100 , by increasing a partial mass m which is the mass of a vibrating element or by increasing a vibrational displacement x of the vibrating element. 
         G= ( −m·x·w   2 )/ M   [Equation 1]
 
     The present invention provides the structure of the touch screen device  100  which is adapted to the above-mentioned methods of increasing the vibrational force G. 
     As shown in  FIG. 1 , the touch screen device  100  according to the present invention includes the touch screen panel  110 . The image display  120  is provided under the touch screen panel  110 . The rigid body  130  is connected to the lower surface of the image display  120  through a first connector  121 . The lower support  140  is connected to the lower surface of the rigid body  130  through second connectors  131 . 
     The touch screen panel  110  is transparent and flexible and functions as a signal input surface which enables a user to observe an image displayed on the image display  120  and press it to input a signal. For instance, the touch screen panel  110  has a rectangular shape which extends a predetermined length in the longitudinal direction of the touch screen device  100 . 
     Furthermore, the touch screen panel  110  is made, for example, by laminating an outer film, an ITO (indium tin oxide) film and a base film. 
     In detail, the outer film is disposed on a front surface of a mobile communication terminal and is sectioned into a viewing area within which touch input is available, and a dead space area which is formed around the viewing area. The outer film is made of transparent film material, such as PET (poly ethylene terephthalate), to allow the user to observe the image display  120  through the outer film. 
     The ITO film is formed by laminating two upper and lower film layers, although it is not in detail shown in the drawings. A dot spacer is interposed between the upper and lower film layers of the ITO film to maintain the distance therebetween constant. An electrode membrane having an X-axis pattern and a Y-axis pattern is provided on the perimeter of each film layer. The X-axis pattern and the Y-axis pattern are electrically separated from each other by an insulator (not shown). The electrode membrane is exposed outside the ITO film through an FPC (flexible printed circuit) cable and is electrically connected to the mobile communication terminal. 
     The base film supports the entire touch panel. For example, a glass substrate having superior transmissivity and a high touch response speed can be used as the base film. 
     The image display  120  is mounted under the touch screen panel  110 . The image display  120  converts a variety of electrical information provided by various units into visual information using the variation of transmittance of a liquid crystal which depends on applied voltage. The image display  120  comprises one or more layers. 
     The touch screen panel  110  may be integrated with the image display  120 . 
     The rigid body  130  which vibrates is mounted under the image display  120 . The vibration units  132  which generate vibrations are provided on the rigid body  130 . The installation location, the shape and the characteristics of each vibration unit  132  which is provided on the rigid body  130  will be explained in detail later with reference to  FIG. 2 . 
     The rigid body  130  is connected to the lower surface of the image display  120  through the first connector  121 . The first connector  121  can systemically separate the touch screen panel  110  and the image display  120  from the rigid body  130 . The first connector  121  may be removed depending on a systemic design of the device. 
     In the embodiment, the first connector  121  comprises a damper and intercepts vibration or impact caused by bending attributable to the application of external force. The damper may include a gel type damper made of solid or liquid. That is, the first connector  121  comprises the damper which is formed by applying liquid material and irradiating UV rays thereupon. Thus, the first connector  121  systemically divides the mass of the device. 
     The lower support  140  is connected to the lower surface of the rigid body  130  by the second connectors  131 . 
     The lower support  140  comprises a circuit board or a casing. The second connectors  131  can systemically separate the rigid body  130  from the lower support  140 . The second connectors  131  may be removed depending on the systemic design of the device. 
     In the embodiment, each second connector  131  comprises a damper and intercepts vibrations or impact caused by bending attributable to an external force being applied. The damper may include a gel type damper made of solid or liquid. In other words, the second connector  131  comprises the damper which is formed by applying liquid material and irradiating UV rays thereupon and thus systemically divides the mass of the device. 
     Furthermore, third connectors  122  connect the touch screen panel  110  to the lower support  140 . The third connectors  122  can systemically separate the touch screen panel  110  from the lower support  140 , and they may be removed depending on the systemic design of the device. 
     In the embodiment, each third connector  122  comprises a damper and intercepts vibrations or impact caused by bending attributable to an external force being applied. The damper may include a gel type damper made of solid or liquid. That is, the third connector  122  comprises the damper which is formed by applying liquid material and irradiating UV rays thereupon and thus systemically divides the mass of the device. 
     In the present invention, the vibration units  132  are provided on the rigid body  130  which is systemically separated from the lower support  140 . Thus, vibrations generated from the vibration units  132  are prevented from being transmitted to the lower support  140  through the second connectors  131 . Thereby, the total mass M of the part which is vibrated by the vibrating element is reduced. 
     Therefore, according to [Equation 1], the vibrational force G of the upper parts which are touched by the user can be increased by reducing the total mass M of the part which is vibrated by the vibrating element, thus maximizing a sensation of vibration transmitted to the user. 
     As shown in  FIG. 2 , the vibration units  132  which generate vibrations are provided on the rigid body  130 . 
     Each vibration unit  132  comprises a piezoelectric (or polymer) actuator or motor which can be formed thin and generate vibrations in such a way that it is expanded and contracted by external power in the longitudinal direction. 
     The shape of the vibration unit  132  is not limited to a special shape and, generally, it has a bar shape. The installation location of the vibration unit  130  is also not limited and, generally, it is provided in the perimeter of the rigid body  130 . 
     In the embodiment, the second connectors  131  are coupled to the edge of the rigid body  130  to systemically separate the rigid body  130  from the lower support  140 . The vibration units  132  are fastened to the rigid body  130 . Hence, the vibration units  132  are prevented from being damaged, for example, by falling, and the strength thereof is improved. 
     Furthermore, weights  133  are mounted to the rigid body  130  on which the vibration units  132  are provided, so that the mass of the rigid body  130  that vibrates along with the vibration units  132  is increased, thus maximizing the vibrational force G. In addition, vibrational force generated by mass eccentricity can be used (refer to Equation 1). 
     Each weight  133  is typically made of material having high density, for example, tungsten. The weight  133  can be located at any position on the rigid body. In other words, the installation location of the weight  133  is not restrained, for instance, it may be mounted to the central portion of the rigid body  130 . 
     The second connectors  131  which are connected to the edge of the rigid body  130  space the rigid body  130  apart from the lower support  140  and function as shock absorbers for the lower support  140  when the rigid body  130  vibrates. 
     As such, in the touch screen device  110  according to the present invention, the weights  133  are mounted to the rigid body  130  so that the partial mass m which is the mass of the vibrating element is increased. Thereby, the vibrational force G can be increased. 
       FIG. 3  illustrates elastic members  135  mounted to the rigid body  130 . The elastic members  135  are provided on the perimeter and the central portion of the rigid body  130 . 
     The elastic members  135  function to minimize abrasion of the rigid body  130  when operating in the vertical direction and to increase a vibrational displacement x to maximize the vibrational force G (refer to Equation 1). 
     The elastic members  135  can be disposed at any locations on the rigid body  130 , in other words, the installation locations thereof are not restrained. In addition, each elastic member  135  can be made of any material, if it is of an appropriate elasticity which is capable of increasing the displacement thereof. 
     Here, particularly, the elastic members  135  which are provided on the central portion of the rigid body  130  prevent the vibration units  132  which move upwards and downwards when vibrating from coming into contact with other elements, thus preventing noise and abrasion of the vibration unit  132 . 
     Furthermore, the frequency of the rigid body  130  may be changed depending on the shape of the elastic member  135 . The shock absorption effect of the elastic member  135  when the vibration unit  132  vibrates can be further increased by attaching an additional liquid or solid damper to the elastic member  135 . 
     In the embodiment, each elastic member  135  may comprise a coil spring or a plate spring. 
       FIG. 4  illustrates the second connectors  131 , the vibration units  132 , the weights  133 , and the elastic members  135  which are mounted to the rigid body  130 . 
       FIG. 5  illustrates plate type elastic members  136  provided on the rigid body  130 . In this case, when the rigid body  130  vibrates upwards and downwards, the elastic members  136  are elastically operated in such a way that the plates are expanded and contracted in the longitudinal direction. 
       FIG. 6  is a side view of the structure in which the vibration units  132  and the elastic members  135  are mounted to the rigid body  130  and the second connectors  131  are to coupled to the edges of the rigid body  130 . 
     The structure of  FIG. 6  illustrates only one example, and the shapes and sizes of the vibration units  132  and the elastic members  135  are not restrained. The locations at which the vibration units  132  are mounted to the rigid body  130  are also not restrained. 
       FIG. 7  illustrates the structure of a rigid body  130  which can provide elastic energy by itself. In this case, the strength of the rigid body  130  becomes superior. Because elastic portions  137  which function to increase a vibrational displacement x are integrally formed in the perimeter of the rigid body  130 , the space in which the rigid body  130  can move is increased. 
     The touch screen device  100  according to the present invention reduces the total mass M of the part which is vibrated by the vibrating element, increases the partial mass m that is the mass of the rigid body  130  which vibrates using the vibration units  132 , and increases the vibrational displacement x of the rigid body  130  which vibrates along with the vibration units  132 . Therefore, the vibrational force of the device can be maximized. 
     Furthermore, it is unnecessary to increase the size of the vibration unit  132  which is made of expensive material, to increase the vibrational force. In other words, the present invention can reduce the size of the vibration unit  132 , thus reducing the production cost of the touch screen device  100 . 
     In addition, because the vibration units  132  are fastened to the rigid body  130 , the vibration units  132  can be prevented from being damaged, for example, by falling. Thus, the strength of the touch screen device  100  can be improved. As well, the modularization of the rigid body  130 , the vibration units  132  and the first connector  121  can be realized. 
     Moreover, the frequency of the rigid body  130  can be changed depending on the shape of the elastic members  135 ,  136  or the elastic portions  137 . 
     Although the embodiments of the present invention have been disclosed for illustrative purposes, it will be appreciated that a touch screen device according to the invention is not limited thereby, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention. 
     Accordingly, any and all modifications, variations or equivalent arrangements should be considered to be within the scope of the invention, and the detailed scope of the invention will be disclosed by the accompanying claims.