JP2003166826A - Opening and closing detecting switch for foldable portable terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an opening and closing detecting switch for a foldable portable terminal with superior durability which can be inexpensively realized by only known electronic parts and without requiring new electronic parts. <P>SOLUTION: In the foldable portable terminal with a body part and a lid body part mutually attached so as to open and close, a speaker 22 (a magnet) is provided in the lid body part and a geomagnetic sensor 14 is provided in the body part. The geomagnetic sensor 14 detects a magnetic field formed by the magnet of the speaker 22. A judging process part 3 refers to a table DT defining a correspondence relationship between an opened/closed state of the lid body part and the magnetic field formed by the speaker 22, and it judges the opened/closed state of the lid body part on the basis of the magnetic field detected by the geomagnetic sensor 14. By this, the opened/closed state of the lid body part with respect to the body part is detected. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an open / close detection switch for detecting the open / closed state of a so-called foldable mobile terminal such as a mobile phone.

[0002]

2. Description of the Related Art In a mobile phone, which is a type of mobile terminal, an information processing function has been significantly enhanced in addition to a conventional call function. By the way, considering the function as an information processing terminal, a large information display unit is preferable, but if the display unit is enlarged as it is, portability is significantly impaired. Therefore, a foldable mobile terminal that has both portability and convenience as a mobile terminal has become mainstream by opening and closing the cover body part where the display part is arranged to the main body part where the input keys are arranged. ing.
Further, in recent years, a mobile terminal having a compass function for presenting directions of north-south north-east and west has been proposed, and further multifunctionalization is being promoted.

[0003]

By the way, in the case of a foldable type portable terminal, when using it, the user has to make a call or input information while keeping the lid open. Some have a power supply control function for automatically controlling on / off of the power supply by opening the lid part. In order to realize this power supply control function, a switch for detecting the open / closed state of the lid body (hereinafter referred to as “open / close detection switch”) is required.

FIG. 5 shows an example of an open / close detection switch provided in a conventional mobile phone. The example shown in FIG. 3A uses a mechanical switch and includes a protrusion MS that is connected to an electrically movable contact. When the lid body is closed, the protrusion MS is pushed. As a result, the connection state of the electrical movable contact is switched, and the open / closed state of the lid portion is detected.
Further, in the example shown in FIG. 7B, a small Hall element HD and a magnet MG are combined to form an open / close detection switch, and these are arranged at corresponding positions on the main body side and the lid side, respectively. To do. According to this example, when the magnet MG approaches the Hall element HD, a voltage based on the Hall effect appears in the Hall element HD, and thereby the open / closed state of the lid portion is detected.

However, according to the above-mentioned conventional open / close detection switch, since the switch itself exists in the apparatus as an independent electronic component, there is a problem that component cost and mounting space are required. Further, the mechanical switch is relatively inexpensive, but has a problem of poor durability. Further, a switch using a small Hall element and a magnet has excellent durability because it functions as a non-contact type contact, but it is relatively expensive and there is a problem that the cost of parts increases. Moreover, there is a problem that the Hall element has a low sensitivity and a separate magnet is required to detect magnetism.

The present invention has been made in view of the above circumstances, and is capable of opening and closing a foldable portable terminal which is excellent in durability and can be realized at low cost only with existing electronic components without requiring new electronic components. The purpose is to provide a detection switch.

[0007]

In order to solve the above problems, the present invention has the following constitution. That is, the open / close detection switch of the folding portable terminal according to the present invention corresponds to the first body portion (for example, a component corresponding to the main body portion 10 described later) and the second body portion (for example, the lid body portion 20 described later). Is a switch for detecting the open / close state of the foldable portable terminal, the magnet being provided in the second body portion (for example, a component corresponding to a speaker 22 for a telephone call to be described later). ), A magnetic sensor (for example, a component corresponding to a geomagnetic sensor 14 described later) that is provided in the first body portion and detects a magnetic field formed by the magnet, and opening and closing of the first and second body portions. Based on a table (for example, a component corresponding to a decoder table DT described later) in which the correspondence between the states and the magnetic field formed by the magnet is defined, and the magnetic field detected by the magnetic sensor. A determination processing unit (for example, a component corresponding to a circuit system including a decoder 5, a controller 6, and a memory 7, which will be described later) that determines the open / closed state of the first and second body units by referring to the table. It is characterized by that.

According to this structure, the magnetic field of the magnet detected by the magnetic sensor changes depending on whether the first and second body parts are in the closed state or in the open state. The determination processing unit refers to a table in which the correspondence relationship between the magnetic field and the open / closed state is defined in advance, to thereby determine the relative relationship between the first body portion and the second body portion corresponding to the magnetic field detected by the magnetic sensor. Grasp the open / closed state. This functions as a switch that detects the open / closed state of the first and second body portions.
By thus determining the open / closed state by referring to the table, not only the binary determination of the open state and the closed state but also the 3
It is possible to make a multivalued judgment that is equal to or greater than the value. Moreover, by rewriting the table, it becomes possible to adaptively change the judgment criterion of the open / closed state.

The magnetic sensor also serves as a geomagnetic sensor for a compass (for example, a constituent element corresponding to a geomagnetic sensor 14 described later), and the magnet serves as a speaker for a call (for example, a constituent element corresponding to a speaker 22 described later). ) Is also used. According to this configuration, it becomes possible to detect a change in the magnetic field according to the open / closed state, without requiring a new electronic component. Further, the determination processing unit is configured to subtract a predetermined magnetic field component other than the geomagnetism when the first and second body parts are in the open state from the magnetic field detected by the magnetic sensor. Is characterized by. According to this configuration, it is possible to accurately detect the open / closed state without sacrificing the accuracy of geomagnetic detection.

Furthermore, the magnetic sensor is the first magnetic sensor.
And the second body part is attached to the first body part so as to be located in the vicinity of the magnet when the second body part is in the closed state. According to this configuration, since the magnetic field detected by the magnetic sensor in the closed state becomes strong, it is possible to stably detect the closed state. Furthermore, the determination processing unit is configured to perform the first and second conditions on the condition that an incoming call is received.
It is configured to determine the open / closed state of the body part of the. According to this configuration, since the determination process is executed after the incoming call, it is possible to suppress the current consumption associated with the determination process as a whole.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (Description of Configuration) FIG. 1 shows an external configuration of a mobile terminal according to this embodiment. This mobile terminal is a foldable mobile phone, and as shown in FIG. 1A, the main body section 10 (first body section) and the lid section 20 (second body section) are roughly illustrated. The main body 10 and the lid 20 are attached to each other so as to be openable and closable. One body part 10
Various input keys 11 such as numeric keys and a microphone 12 for communication are provided in the. In addition, a substrate 13 on which a circuit for performing various processes as a mobile terminal is formed is incorporated inside the main body 10. Further, this portable terminal has a so-called electronic compass function and has a built-in geomagnetic sensor 14 for that purpose.

A display portion 21 for displaying various information processed by the circuit on the substrate 13 is provided on the other lid portion 20.
A speaker 22 for communication and an antenna 23 are provided. Here, as shown in FIG.
On the other hand, with the lid body 20 closed, the geomagnetic sensor 1
4 is attached to the main body 10 side so as to be located in the vicinity of the speaker 22 provided on the lid body 20 side. The geomagnetic sensor 14 and the speaker 22 are the main body 1
0 is also used as a component of an open / closed detection switch for detecting a relative open / closed state between the cover body 20 and the cover body 20.

FIG. 2 shows a functional configuration of the portable terminal according to this embodiment. The mobile phone block 1 realizes a function as a mobile phone, and includes a mobile phone communication module 1A, a keyboard 1B, a liquid crystal display (LC).
D: Liquid Crystal Display) 1C.
The mobile phone communication module 1A is mounted on the above-mentioned substrate 13, the keyboard 1B is attached to the main body portion 10 as the above-mentioned input keys 11, and the liquid crystal display 1C is attached to the lid body portion 20 as the above-mentioned display portion 21. There is.
GPS module 2 (GPS: Global Positioning Sys
tem) is for acquiring position information using radio waves transmitted from an artificial satellite, and realizes an electronic compass function together with the geomagnetic sensor 14.

The geomagnetic sensor 14 is constructed so as to detect weak magnetism by utilizing, for example, the magnetic impedance effect, and as shown in FIG. 3, the X-axis detecting the magnetic component in the X-axis direction. It is composed of a magnetic sensor 14A, a Y-axis magnetic sensor 14B that detects a magnetic component in the Y-axis direction, and a constant current bias control circuit 14C that supplies an operating current to these magnetic sensors. From the X-axis and Y-axis magnetic sensors 14A and 14B, detection voltage signals VX and VY corresponding to the magnetic field strengths in the respective axial directions are extracted. The constant current bias control circuit 14C is supplied with a control signal SC for controlling the on / off state of the constant current bias control circuit. The geomagnetic sensor 14 is basically for realizing an electronic compass function, but when it is also used as an open / close detection switch, for detecting the magnetic field formed by the magnet of the speaker 22 for communication. Used as.

The judgment processing section 3 judges the open / closed state between the main body section 10 and the lid section 20 based on the detection result of the geomagnetic sensor 14, and comprises a decoder 3A, a controller 3B and a memory 3C. The mobile phone block 1 and the GPS module 2 are connected via the bus 8. The decoder 3A decodes the detection voltage signals VX and VY obtained by the geomagnetic sensor 14 to generate azimuth information, and a table (hereinafter, referred to as "decoder table") DT referred to in the decoding operation.
Built in. However, this table DT may be stored in the memory 3C described later. The decoder table DT will be described later.

The controller 3B controls each part in accordance with a predetermined control program, determines the open / closed state by receiving the decoding result of the decoder 3A, and the processing required to realize the electronic compass function. Also run. The memory 3C is a ROM (Read Only Memo).
and a control program executed by the controller 3B described above. The determination processing unit 3, the magnetic sensor 14, and the speaker 22 described above.
Configures an open / close detection switch 100 for detecting the open / closed state between the main body 10 and the lid 20.

FIG. 4 shows an example of the structure of the decoder table DT provided in the above-mentioned decoder 3A. This decoder table DT shows the magnetic field strength (Oe) and the azimuth angle / inclination angle (deg) in the X-axis direction and the Y-axis direction represented by the detection voltage signals VX and VY of the geomagnetic sensor 14 according to the geomagnetic vector in Japan. The correspondence is tabulated. The tilt angle represents the tilt of the mobile terminal body with respect to the horizontal plane.
Note that, in FIG. 4, for convenience of description, the correspondence relationship between the magnetic field strength (Oe) and the azimuth angle (deg) is shown, but the detection voltage signals VX and VY may be used as they are instead of the magnetic strength.

Here, the horizontal component of geomagnetism in Japan is
Generally, it is in the range of -0.3 to +0.3 (Oe), but when the mobile terminal tilts from the horizontal plane, the geomagnetic sensor reacts to the vector component of geomagnetism, and the detected value exceeds 0.3 (Oe). There is. Therefore, in the example shown in FIG. 4, the level of the geomagnetism is regulated within the range of −0.35 (Oe) to +0.35 (Oe), which corresponds to the case where the mobile terminal is tilted. In the case of the decoder table DT shown in this example, both the azimuth and the inclination can be detected with an accuracy of at least 1 degree.

The decoder table DT also defines table values when the speaker 22 and the geomagnetic sensor 14 function as open / close detection switches. That is, the decoder table DT describes table values that define the correspondence between the open / closed state of the main body 10 and the lid 20 and the magnetic field formed by the magnet of the speaker 22. Here, as shown in FIG. 1B, when the lid 20 is closed with respect to the main body 10, the geomagnetic sensor 14 and the speaker 22 are extremely close to each other, so that the detection of the geomagnetic sensor 14 is performed. The voltage signals VX and VY become abnormally high. Therefore, in this example, a high magnetic field is detected with a threshold value of 1 (Oe), and a table value representing a "closed state" is defined in association with a magnetic field strength of 1 (Oe) or more, and less than 1 (Oe). The table value representing the "open state" is defined in association with the magnetic field strength of.

Next, the operation of this embodiment will be described focusing on the open / close detection switch 100. Note that, for convenience of explanation, it is assumed that the lid body portion 20 is in the open state and the power is turned on in the initial state. When the lid portion 20 is changed from the initial state (open state) to the closed state as shown in FIG. 1B, the speaker 22 for communication comes to be located near the geomagnetic sensor 14. Therefore, the levels of the detection voltage signals VX and VY of the geomagnetic sensor 14 exceed 1 (Oe). The decoder 3A refers to the decoder table DT shown in FIG. 4 based on this detection voltage signal, acquires the table value corresponding to the closed state, and outputs this as the decoding result.

The controller 3B determines that the lid 20 is in the closed state based on the table value output from the decoder 3A, and outputs a notification signal to that effect to the mobile phone block 1. In the mobile phone block 1, the power for each unit is turned off, leaving the function for judging an incoming call from the outside, and the mobile phone block 1 and the GPS module 2 are placed in a standby state until an incoming call is received. After that, the controller 3B turns off the constant current bias circuit 14C of the geomagnetic sensor 14 to turn off the X-axis magnetic sensor 14A and the Y-axis magnetic sensor 14.
By stopping the supply of the current to B, the current consumption in the geomagnetic sensor 14 is suppressed.

Then, when there is an incoming call in the above-mentioned standby state, an incoming call signal is output from the mobile phone block 1 to the controller 3B via the bus 8. Controller 3B
Controls the constant current bias circuit 14C of the geomagnetic sensor 14 to the ON state on condition that an incoming call is received, and supplies a current to the X-axis magnetic sensor 14A and the Y-axis magnetic sensor 14B. As a result, it becomes possible to detect the geomagnetism. In parallel with this, the mobile phone block 1 generates a ring tone and notifies the user that there is an incoming call.

Then, the user can use the lid portion 20 for a call.
Is opened, the speaker 22 is far away from the geomagnetic sensor 14, and the detection voltage signal V of the geomagnetic sensor 14 is released.
The levels of X and VY become smaller than 1 (Oe). As a result, the detection voltage signals VX and VY settle at a level according to the strength of the earth's magnetism. The decoder 3A receives the detection voltage signals VX and VY, refers to the decoder table DT, and outputs a table value corresponding to the open state. The controller 3B determines that it is in the open state based on this table value, and outputs a notification signal to that effect to the mobile phone block 1.

The mobile phone block 1 is a controller 3B.
Upon receiving the notification signal from, the power of each part is turned on. This enables a call. After this, controller 3
B is a constant current bias control circuit 14 of the geomagnetic sensor 14.
C is controlled to the off state to suppress the current consumption generated in this constant current bias control circuit. Further, when the user specifies the electronic compass function with the power turned on in this way, the geomagnetic sensor 14 detects geomagnetism according to changes in the azimuth angle and the tilt angle, and the detected voltage signals VX, VY.
Generate.

In this case, the main body portion 10 and the lid portion 20 are in the open state, and the geomagnetic sensor 14 and the speaker 22 are separated from each other.
Is almost unaffected by the magnetism of the
X and VY indicate levels according to the strength of the earth's magnetism. The decoder 3A refers to the decoder table DT based on the detection voltage signals VX and VY, and acquires the table value of the corresponding azimuth angle. The controller 3B receives the table value and causes the display unit 21 to display the orientation information (electronic compass function).

Here, the stronger the magnetic field generated by the magnet of the speaker 22, the higher the level of the detection voltage signals VX, VY obtained by the geomagnetic sensor 14, and the stable and accurate detection of the closed state becomes possible. However, if the magnetic field on the side of the speaker 22 is increased, the magnetic field of the speaker 22 may affect the magnetic sensor 14 when it functions as the electronic compass function in the open state, and the accuracy of the electronic compass may decrease. As a countermeasure against this, a magnetic field component (predetermined magnetic field component) other than geomagnetism is grasped in advance by measurement, and from the magnetic field detected by the geomagnetic sensor 14,
It suffices to subtract the magnetic field components other than the geomagnetism. Such magnetic field components other than the earth magnetism are set in, for example, the RAM area in the controller 3B as a bias value for the magnetic field when the electronic compass is made to function.

The magnetic field component other than the above-mentioned geomagnetism is a magnetic field component generated by a circuit inside the portable terminal incorporating the open / close detection switch 100, a liquid crystal display, etc., and is a substantially constant amount. However, when the magnetic field component internally generated changes according to the operation mode, for example, this magnetic field component is measured in advance for each operation mode and tabulated, and by referring to this table, the geomagnetic sensor 14 can The amount (predetermined magnetic field component) to be subtracted from the detected magnetic field may be corrected.

Next, when the user finishes the call (use of the mobile phone) and closes the lid portion 20, the magnetic intensity detected by the geomagnetic sensor 14 becomes 1 (Oe) or more, and the decoder 3A
Outputs the table value corresponding to the closed state. The controller 3B determines that the lid 20 is in the closed state based on the table value. Then, as described above, the notification signal indicating that is output to the mobile phone block 1 and
The constant current bias control circuit 14C is controlled to the off state.
As a result, the power of the mobile terminal is turned off again, and the mobile terminal enters the standby state. As described above, the open / close detection switch 100
Thus, the open / closed state of the lid portion 20 with respect to the main body portion 10 is detected, and the on / off of the power source is accurately controlled.

According to this embodiment, the geomagnetic sensor 1
4 and the speaker 22 are existing components, and the decoder 3A and the controller 3B of the determination processing unit 3 can be realized by software, and further, the memory 3C.
Can utilize a part of the existing ROM area. Therefore, the open / close detection switch 100 can be realized without newly preparing electronic components. Further, since the constant current bias control circuit 14C is controlled to be in the OFF state after detecting the open / closed state, it is possible to suppress the current consumption.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and the present invention can be applied even if there are design changes and the like within a range not departing from the gist of the present invention. included. For example, in the above-described embodiment, the geomagnetic sensor 14 is provided in the main body 10 and the speaker 2
The microphone 12 detects the magnetic field generated by the microphone 2.
If it is of a type including a magnet, the geomagnetic sensor 14 may be provided on the side of the lid 20 to detect the magnetic field generated by the microphone 12.

Further, in the above-described embodiment, the main body 10
Although the portable terminal is composed of the lid portion 20 and the lid portion 20, it is not limited to the case of the master-slave relationship as described above, and the two equal body portions are two.
A foldable combination is also included in the concept of the present invention, and the master-slave relationship of each body is not an essential matter of the present invention. Furthermore, although the judgment processing unit 3 is realized by software, it may be realized as a circuit. Needless to say, only some of the functions (for example, the decoder 3A) may be realized on the circuit.

Furthermore, in the above-mentioned embodiment, the mobile phone has been described as an example, but it can be applied to other mobile terminals such as a notebook personal computer. Furthermore, in the above-described embodiment, the open / close detection switch 100 is configured by also using the existing speaker 22 and the geomagnetic sensor 14, but it may be configured by a dedicated electronic component instead of using them as well. Good. This makes it possible to reduce the processing load on the software. Furthermore, a plurality of types of decoder tables may be prepared according to the operation mode. As a result, it is possible to accurately detect the geomagnetism in each operation mode.

[0033]

As described above, according to the present invention, the magnetic sensor provided in the first body portion detects the magnetic field formed by the magnet provided in the second body portion, and the magnetic sensor is provided. Since the open / closed state of the second body part with respect to the first body part is determined from the change in the magnetic field detected by, it is possible to realize inexpensively with only existing electronic parts without newly requiring electronic parts. It is possible to provide an open / close detection switch for a foldable mobile terminal which is capable of achieving excellent durability. Moreover, since the open / closed state is determined using the table, it is possible to adaptively correct the determination reference according to the operating state, and it is possible to accurately determine the open / closed state.

Further, since the magnetic sensor also serves as a geomagnetic sensor for realizing the compass function, and the magnet also serves as a microphone or a speaker for a call, the switch function can be performed without newly preparing electronic parts. Can be realized. Furthermore, since the open / closed state is determined on the condition that there is an incoming call, the current consumption can be suppressed. Furthermore, since the magnetic sensor is attached to the first body so as to be located near the magnet in the closed state, the closed state can be detected stably and accurately.

[Brief description of drawings]

FIG. 1 is a diagram showing an external configuration example of a mobile terminal (mobile phone) according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a functional configuration example of a mobile terminal (mobile phone) according to the embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration example of a geomagnetic sensor according to the embodiment of the present invention.

FIG. 4 is a diagram showing an example of a decoder table according to the embodiment of the present invention.

FIG. 5 is a diagram showing an example of an external configuration of a mobile phone according to a conventional technique.

[Explanation of symbols]

1: Mobile phone block, 1A: Mobile phone communication module, 1B: Keyboard, 1C: Liquid crystal display (LC
D), 2: GPS module, 3: determination processing unit, 3A:
Decoder, 3B: Controller, 3C: Memory, 8: Bus, 10: Main body, 11: Input key, 12: Microphone, 1
3: substrate, 14: geomagnetic sensor, 14A: X-axis magnetic sensor, 14B: Y-axis magnetic sensor, 14C: constant current bias control circuit, 20: lid part, 21: display part, 22: speaker, 23: antenna, 100: Open / close detection switch, D
T: Decoder table.

Claims (5)

[Claims] 1. An open / close detection switch for a foldable portable terminal, wherein a first body portion and a second body portion are attached to each other so as to be openable and closable, and a magnet provided in the second body portion, A magnetic sensor provided in the first body portion for detecting a magnetic field formed by the magnet, and a correspondence relationship between an open / closed state of the first and second body portions and a magnetic field formed by the magnet are defined. A foldable mobile phone, comprising: a table; and a determination processing unit that determines the open / closed state of the first and second body parts by referring to the table based on the magnetic field detected by the magnetic sensor. Terminal open / close detection switch. 2. The open / close detection switch for a foldable portable terminal according to claim 1, wherein the magnetic sensor also serves as a geomagnetic sensor for a compass, and the magnet also serves as a speaker for communication. 3. The determination processing unit is configured to perform the first and second
The foldable mobile phone according to claim 2, wherein a predetermined magnetic field component other than the earth magnetism when the body part of the vehicle is in the open state is configured to be subtracted from the magnetic field detected by the magnetic sensor. Terminal open / close detection switch. 4. The magnetic sensor includes the first and second magnetic sensors.
The foldable portable terminal according to any one of claims 1 to 3, wherein the foldable portable terminal is attached to the first body portion so as to be located in the vicinity of the magnet when the body portion is closed. Open / close detection switch. 5. The determination processing section is configured to determine the open / closed state of the first and second body sections on the condition that an incoming call is received.
An open / closed detection switch for a foldable mobile terminal according to any one of 1.