WO2014061665A1 - Charging cradle for electronic device - Google Patents

Abstract

The purpose of the present invention is to provide a charging cradle for an electronic device which correctly detects abnormal heating due to a malfunction in an output contact part by accurately measuring the atmospheric temperature and the temperature of an output terminal, thereby avoiding failure and maintaining the safety of a device in a charging cradle that handles a large amount of current. The present invention comprises: output terminals (131, 132, 134, 135) connectable to charging terminals (31, 32, 34, 35) of an electronic device (1); a substrate (120) having power supply patterns (121, 122) connected to the output terminals; a case (136) arranged on the substrate to cover the part of the output terminals that is connected to the power supply patterns; and a thermistor (150) which can measure temperature. The case (136) has a recessed portion (137), and the thermistor (150) is arranged at a position corresponding to the recessed portion (137) of the case (136) on the substrate.

Description

Charging stand for electronic devices

The present invention relates to a charging stand for electronic equipment such as a portable terminal device.

Conventionally, a charging stand (cradle) for charging a built-in battery of an electronic device such as a portable terminal device has been known (see Patent Document 1 below). Some of this type of charging stand includes a thermistor that measures temperature to detect abnormal heat generation. Generally, a thermistor monitors the internal temperature of the charging stand, and when the temperature exceeds a specified temperature, a specified electrical circuit operates to stop the power supply from the charging stand to the electronic device. It is.

In such a charging stand, the thermistor is generally arranged on a printed circuit board inside the charging stand and measures the ambient temperature inside the charging stand or is attached to a heat generating component (semiconductor etc.) of the power supply circuit. And measuring the temperature of the heat generating component.

JP 2010-200445 A

By the way, since the output terminal of the charging stand has a certain resistance value, when charging is performed with a current larger than a charging current generally used, heat is greatly generated. Furthermore, when the connection terminal portion having a certain resistance value is heated due to a short circuit caused by a foreign substance or a contact failure of the contact portion at the connection portion between the output terminal of the charging stand and the charging terminal of the electronic device, the above method is used. Then, there is a possibility that abnormal heat generation in the terminal portion cannot be detected.

The present invention accurately measures the ambient temperature and the temperature of the output terminal in a charging stand that handles a large current, thereby correctly detecting abnormal heat generation due to a trouble in the output contact portion, and avoiding the safety and failure of electronic equipment. An object is to provide a charging stand for electronic equipment.

The present invention provides an output terminal connectable to a charging terminal of an electronic device, a substrate having a power supply pattern connected to the output terminal, and disposed on the substrate, and the power supply pattern among the output terminals. A case portion covering a connected portion; and a thermistor capable of measuring temperature; the case portion having a recess on the substrate side; the thermistor on the substrate; The present invention relates to a charging stand for electronic equipment disposed at a position corresponding to the recess.

The present invention further includes a control circuit that cuts off power to the output terminal based on a temperature measured by the thermistor, and the control circuit includes the power supply pattern connected to the output terminal. You may arrange | position to the separate board | substrate isolate | separated from the said board | substrate which has.

The thermistor may be disposed on the substrate at a position spaced from the power supply pattern by a predetermined distance.

The output terminal includes a plus output terminal and a minus output terminal, and the power supply pattern is connected to a plus power supply pattern connected to the plus output terminal and the minus output terminal. The thermistor may have a negative power supply pattern, and the thermistor may be disposed at a predetermined distance from both the positive power supply pattern and the negative power supply pattern.

In addition, the present invention further includes an auxiliary component having a resistance high enough not to affect the operating resistance region of the thermistor and having good heat conduction characteristics, and the auxiliary component includes the thermistor and the plus side output terminal. And the position where the thermistor and the negative output terminal are connected to each other.

According to the present invention, both the temperature of the output terminal and the ambient temperature can be measured efficiently, and the energization to the output terminal can be cut off based on both temperatures.

It is a perspective view which shows an example of the portable terminal device as an electronic device with which it mounts | wears with the charging stand for electronic devices of this invention, and is charged. It is a rear view which shows an example of the portable terminal device as an electronic device with which it mounts | wears with the charging stand for electronic devices of this invention, and is charged. It is a front view which shows 1st Embodiment of the charging stand for portable terminal devices as a charging stand for electronic devices of this invention. It is a side view which shows 1st Embodiment of the charging stand for portable terminal devices as a charging stand for electronic devices of this invention. It is a front view which shows the state which mounted | wore the 1st Embodiment of the charging stand for portable terminal devices as a charging stand for electronic devices of this invention with the portable terminal device mounted | worn. It is a side view which shows the state which mounted | wore 1st Embodiment of the charging stand for portable terminal devices as a charging stand for electronic devices of this invention with the portable terminal device mounted | worn. It is the figure which looked at the printed circuit board containing an output terminal from the extension direction of an output terminal in the charging stand for portable terminal devices of a 1st embodiment, and omits and shows a case part. It is the figure which looked at the printed circuit board containing an output terminal in the charging stand for portable terminal devices of 1st Embodiment from the direction orthogonal to the extension direction of an output terminal, and shows a case part removed. It is the figure which looked at the printed circuit board containing an output terminal from the extension direction of an output terminal in the charging stand for portable terminal devices of a 1st embodiment, and shows the state where a case part was attached. It is the figure which looked at the printed circuit board containing an output terminal from the direction orthogonal to the extension direction of an output terminal in the charging stand for portable terminal devices of 1st Embodiment, and shows the state in which the case part was attached. It is a circuit diagram which shows the control circuit which turns on / off the electric power feeding to an output terminal according to the measured temperature of a thermistor in the charging stand for portable terminal devices of 1st Embodiment. It is the figure which looked at the printed circuit board containing an output terminal from 2nd Embodiment of the charging stand for portable terminal devices as a charging stand for electronic devices of this invention from the extension direction of an output terminal, and abbreviate | omits and shows a case part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, a portable terminal device will be described as an electronic device mounted on the electronic device charging base, but the electronic device mounted on the electronic device charging base of the present invention is not limited to this. Below, the charging stand for portable terminal devices as a charging stand for electronic devices to which a portable terminal device as an electronic device is mounted will be described.

1 and 2 show an example of a portable terminal device 1 as an electronic device. The mobile terminal device 1 generally has a parallelepiped shape. The six surfaces constituting the mobile terminal device 1 are, for example, a front surface 11 including a touch screen display 2 as a display unit, a back surface 12 including a charging terminal unit 3, and a front surface 11 in a state where the mobile terminal device 1 is in a vertically long posture. The left surface 13 located on the left when viewed from the right, the right surface 14 provided with the power key 4 located on the right, the upper surface 15 located on the upper side, and the lower surface 16 located on the lower side. Each of these surfaces 11 to 16 is not limited to a flat surface but may be a curved surface. Other components of the mobile terminal device 1 will not be described in the present specification, and thus description thereof will be omitted.

The charging terminal unit 3 includes five hole-shaped terminals 31, 32, 33, 34, and 35 arranged in a line at a predetermined interval from each other. The two terminals including the terminal 31 located at one end and the terminal 32 adjacent thereto are positive charging terminals. The plus side charging terminals 31 and 32 are connected to plus side electrodes of a built-in battery (not shown) of the mobile terminal device 1. The two terminals including the terminal 35 located at the other end and the terminal 34 adjacent thereto are negative charging terminals. The minus side charging terminals 34 and 35 are connected to the minus side electrode of the built-in battery of the mobile terminal device 1. One terminal 33 located in the center is a check terminal for checking whether or not the built-in battery of the mobile terminal device 1 is a genuine product, for example.

FIGS. 3 to 11 show a first embodiment of a charging base 100 for a portable terminal device as a charging base for an electronic device. The portable terminal charging base 100 is also called a cradle. Therefore, hereinafter, the charging terminal 100 for the portable terminal device is also referred to as a cradle 100. As shown in FIGS. 3 to 6, the cradle 100 receives the portable terminal device 1 in a horizontally long posture. That is, the mobile terminal device 1 is mounted at a predetermined position of the cradle 100 with the front surface 11 facing forward, the upper surface 15 facing left, and the lower surface 16 facing right. At this time, the mobile terminal device 1 has a posture in which the right surface 14 facing upward is slightly inclined backward than the left surface 13 facing downward. The cradle 100 includes an output terminal unit 130 at a position corresponding to the charging terminal unit 3 on the back surface 12 of the mobile terminal device 1 when the mobile terminal device 1 is mounted at a predetermined position.

7 and 8, the output terminal unit 130 is attached to the printed circuit board 120. In addition to the output terminal unit 130, the line terminal unit 140 and the thermistor 150 are attached to the printed circuit board 120.

As shown in FIGS. 3, 5, 7, and 8, the output terminal unit 130 includes five pin-shaped terminals 131, 132, 133, 134, and 135 that are arranged in a row at predetermined intervals. . Two terminals including a terminal 131 located at one end and a terminal 132 adjacent to the terminal 131 are plus-side output terminals 131 and 132. The two terminals including the terminal 135 located at the other end and the terminal 134 adjacent thereto are negative output terminals 134 and 135. One terminal 133 located at the center is, for example, a check terminal for checking whether or not the built-in battery of the mobile terminal device 1 is a genuine product.

As shown in FIG. 7, the line terminal unit 140 includes seven line terminals 141 to 147 arranged in a line at a predetermined interval from each other. The printed circuit board 120 has a positive power supply pattern 121 that connects the positive output terminals 131 and 132 and the line terminals 143 and 144, and a negative power that connects the negative output terminals 134 and 135 and the line terminals 146 and 147. A supply pattern 122 and thermistor patterns 123 and 124 for connecting the electrodes 151 and 152 of the thermistor 150 and the line terminals 141 and 142 are provided.

The line terminals 141 and 142 are connected to a control circuit 160 (see FIG. 11) for turning on / off the power supply based on the temperature detected by the thermistor 150. The line terminals 143 and 144 are connected to the DC plus side line of the AC / DC converter 170 (see FIG. 11) of the AC adapter built in the cradle 100. The line terminals 146 and 147 are connected to the DC negative line of the AC / DC converter 170 of the AC adapter built in the cradle 100 (not shown).

8 to 10, the terminals 131 to 135 of the output terminal unit 130 are covered with the case unit 136. The case portion 136 is a so-called mold. Accordingly, the terminals 131 to 135 of the output terminal unit 130 are integrally covered with the case unit 136. The case part 136 has a recess 137 on the printed circuit board 120 side.

The printed circuit board 120 is supported by a movable support (not shown) inside the cradle 100. Therefore, the printed circuit board 120 can be switched between a storage position and a charging position. As shown in FIGS. 3 and 4, when the printed circuit board 120 is in the retracted position, the terminals 131 to 135 of the output terminal unit 130 are mounted surfaces of the cradle 100 (that is, when the mobile terminal device 1 is mounted). From the surface in contact with the back surface 12 of the mobile terminal device 1 to the inside of the cradle 100. As shown in FIGS. 5 and 6, when the printed circuit board 120 is in the charging position, the terminals 131 to 135 of the output terminal portion 130 protrude forward from the mounting surface of the cradle 100.

As shown in FIGS. 3 and 4, when the mobile terminal device 1 is not mounted at a predetermined position of the cradle 100, the output terminal unit 130 is stored in the storage position. As shown in FIGS. 5 and 6, when the mobile terminal device 1 is mounted at a predetermined position of the cradle 100, the output terminal unit 130 is switched to the charging position. Thereby, the plus side output terminals 131 and 132 of the output terminal unit 130 are fitted and connected to the plus side charging terminals 31 and 32 of the charging terminal unit 30 of the mobile terminal device 1. The minus side output terminals 134 and 135 of the output terminal unit 130 are fitted and connected to the minus side charging terminals 34 and 35 of the charging terminal unit 30 of the mobile terminal device 1. The check terminal 133 of the output terminal unit 130 is fitted and connected to the check terminal 33 of the charging terminal unit 30 of the mobile terminal device 1.

The thermistor 150 is a temperature measuring element having a negative resistance temperature coefficient, and is mounted on the printed circuit board 120. Specifically, as shown in FIG. 7, the thermistor 150 is attached to a position on the printed circuit board 120 at predetermined intervals from both the plus-side power supply pattern 121 and the minus-side power supply pattern 122. . This position where the thermistor 150 is attached corresponds to the concave portion 137 of the case portion 136 as shown in FIGS. 9, approximately half the size of the thermistor 150 is disposed inside the recess 137 of the case portion 136, and the remaining approximately half is located outside the case portion 136, as shown in FIG. 9. Be placed.

The control circuit 160 is provided on a board (not shown) different from the printed board 120. As shown in FIG. 11, the control circuit 160 is provided between the AC / DC conversion unit 170 of the AC adapter and the line terminal unit 140. Specifically, the control circuit 160 includes a switching element (for example, an FET switch) 161 and a determination unit 162. The switching element 161 is disposed in the middle of a line connecting the plus side of the AC / DC conversion unit 170 and the plus side terminals (143, 144) of the line terminal unit 140. While the output resistance value of the thermistor 150 exceeds the predetermined threshold level, the detection temperature of the thermistor 150 is lower than the predetermined temperature. Therefore, the determination unit 162 monitors the output of the thermistor 150 and performs switching. The element 161 is maintained in a conductive state. When the output resistance value of the thermistor 150 falls below a predetermined threshold level, the detection temperature of the thermistor 150 exceeds the predetermined temperature, so that the determination unit 162 switches the switching element 161 to the cutoff state.

In the portable terminal charging base 100 described above, while the detected temperature of the thermistor 150 is below a predetermined temperature, the output resistance value of the thermistor 150 is above a predetermined threshold level. Therefore, determination unit 162 maintains switching element 161 in a conductive state based on this output resistance value of thermistor 150. When the detected temperature of the thermistor 150 becomes equal to or higher than a predetermined temperature, the output resistance value of the thermistor 150 falls below a predetermined threshold level. Therefore, the determination unit 162 switches the switching element 161 to the cutoff state based on the output resistance value of the thermistor 150. Thereby, supply of the electric power from the charging terminal 100 for portable terminal devices to the portable terminal device 1 is stopped.

According to the mobile terminal device charging stand 100 of the first embodiment, the following effects can be obtained. According to the present embodiment, the case 136 that is disposed on the printed circuit board 120 having the power supply patterns 121 and 122 connected to the output terminals 131, 132, 134, and 135 and covers the output terminals 131, 132, 134, and 135 is A recess 137 is provided on the printed circuit board 120 side. A thermistor 150 is disposed on the printed circuit board 120 at a position corresponding to the recess 137 of the case portion 136. Therefore, the thermistor 150 can efficiently measure both the temperature of the output terminals 131, 132, 134, and 135 and the ambient temperature, and as a result, the output terminals 131, 132, 134, and 135 are output to the output terminals 131, 132, 134, and 135. It can function as a trigger for a shut-off operation that cuts off the energization.

Also, the present embodiment includes a control circuit 160 that cuts off the power supply to the output terminals 131, 132, 134, 135 based on the temperature measured by the thermistor 150. The control circuit 160 is disposed on a separate substrate that is separated from the printed circuit board 120 having the power supply patterns 121 and 122 connected to the output terminals 131, 132, 134, and 135. Therefore, the control circuit 160 does not need to be affected by thermal troubles that occur on the printed circuit board 120 side, such as heat generation of the output terminals 131, 132, 134, and 135, and can prevent a blocking operation due to a malfunction.

Further, according to the present embodiment, the thermistor 150 is disposed on the printed circuit board 120 at a position spaced from the power supply patterns 121 and 122 by a predetermined distance. Therefore, by determining the attachment position of the thermistor 150, the temperature transmitted from the output terminals 131, 132, 134, 135 to the thermistor 150 via the power supply patterns 121, 122 can be accurately measured.

Further, according to the present embodiment, the output terminals 131, 132, 134, 135 include the plus side output terminals 131, 132 and the minus side output terminals 134, 135. The power supply patterns 121 and 122 include a positive power supply pattern 121 connected to the positive output terminals 131 and 132 and a negative power supply pattern 122 connected to the negative output terminals 134 and 135. The thermistor 150 is disposed at a position spaced apart from both the plus-side power supply pattern 121 and the minus-side power supply pattern 122. Thereby, the temperature transmitted from the plus side output terminals 131 and 132 to the thermistor 150 via the plus side power supply pattern 121, and the temperature transmitted from the minus side output terminals 134 and 135 to the thermistor 150 via the minus side power supply pattern 122. Both can be measured with high accuracy.

In addition, since the temperature of the output terminals 131, 132, 134, and 135 can be measured in this embodiment, it is possible to prevent accidents caused by heat generation due to a short circuit due to a metal object or the like and damage to the mobile terminal device. In addition, since the temperature of the output terminals 131, 132, 134, and 135 is measured in this embodiment, the heat transmitted from the charging terminal of the connected mobile terminal device can also be detected, and thus the abnormal heating of the charging terminal on the mobile terminal device side is detected. Can also be detected to stop power feeding.

FIG. 12 shows a second embodiment of a charging base 200 for a portable terminal device as a charging base for an electronic device. The same parts as those of the charging terminal 100 for the mobile terminal device according to the first embodiment are denoted by the reference numerals obtained by adding 100 to the reference numerals used in the first embodiment, thereby omitting redundant description. In the portable terminal charging base 200, the thermistor 250 and the plus-side power supply pattern 221 are connected by using a high-resistance (alumina material) chip resistor 281 as an auxiliary component. Similarly, the thermistor 250 and the negative power supply pattern 222 are connected using a high-resistance chip resistor 282.

The chip resistors 281 and 282 have high resistance to such an extent that they do not affect the operating resistance region of the thermistor 250 and have good heat conduction characteristics. The resistance value of the thermistor 250 is Rth, the resistance value of the chip resistor 281 is R +, and the resistance value of the chip resistor 282 is R−. In order not to disturb the operation of the thermistor 250, the ratio of the three resistance values of the thermistor 250, the chip resistor 281 and the chip resistor 282 needs to be as follows.
Rth << R +, R-

By connecting the thermistor 250 and the plus side power supply pattern 221 and the thermistor 250 and the minus side power supply pattern 222 by the chip resistors 281 and 282 as described above, the temperature transmitted from the plus side output terminals 231 and 232 to the thermistor 250. Is transmitted through the chip resistor 281, and the temperature transmitted from the negative output terminals 234 and 235 to the thermistor 250 is transmitted through the chip resistor 282.

According to the mobile terminal device charging base 200 of the second embodiment, the following effects are obtained. The present embodiment further includes chip resistors 281 and 282 as auxiliary components that have high resistance to such an extent that they do not affect the operating resistance region of the thermistor 250 and have good heat conduction characteristics. The chip resistors 281 and 282 are arranged at a position connecting the thermistor 250 and the plus side output terminals 231 and 232 and a position connecting the thermistor 250 and the minus side output terminals 234 and 235, respectively. Thereby, the temperature transmitted from the plus side output terminals 231 and 232 and the minus side output terminals 234 and 235 to the thermistor 250 is transmitted via the chip resistors 281 and 282. As a result, the characteristics of the higher temperature region in the thermistor 250 can be used, and therefore the temperature transmitted to the thermistor 250 can be measured with higher accuracy.

In addition, according to the present embodiment, since only the chip resistors 281 and 282 are added as components, it can be configured at low cost.

In the above embodiment, an example in which the present invention is applied to a charging stand for a mobile terminal device has been described. The present invention is not limited to this, and the present invention can be applied to a charging stand for electronic devices other than portable terminal devices, such as tablet terminal devices, PDAs (Personal Digital Assistants), and portable navigation devices.

1 Mobile terminal device (electronic equipment)
31, 32, 34, 35 Charging terminal 100 Charging stand for portable terminal device (charging stand for electronic equipment)
120 Printed circuit board (board)
121 Positive power supply pattern (power supply pattern)
122 Negative power supply pattern (power supply pattern)
131, 132 Positive output terminal (output terminal)
134,135 Negative output terminal (output terminal)
136 Case part 137 Concave part 150 Thermistor 160 Control circuit 281,282 Chip resistance (auxiliary part)

Claims (5)

An output terminal that can be connected to a charging terminal of an electronic device;
A substrate having a power supply pattern connected to the output terminal;
A case portion disposed on the substrate and covering a portion of the output terminal connected to the power supply pattern;
A thermistor capable of measuring temperature,
The case portion has a recess on the substrate side,
The said thermistor is arrange | positioned on the said board | substrate in the position corresponding to the said recessed part of the said case part. The charging stand for electronic devices characterized by the above-mentioned. Based on the temperature measured by the thermistor, further comprising a control circuit for cutting off the energization to the output terminal,
The charging base for an electronic device according to claim 1, wherein the control circuit is disposed on another board separated from the board having the power supply pattern connected to the output terminal. The charging stand for electronic devices according to claim 1, wherein the thermistor is disposed at a position spaced apart from the power supply pattern on the substrate. The output terminal has a positive output terminal and a negative output terminal,
The power supply pattern has a positive power supply pattern connected to the positive output terminal and a negative power supply pattern connected to the negative output terminal.
4. The charging stand for an electronic device according to claim 3, wherein the thermistor is disposed at a position spaced apart from both the plus-side power supply pattern and the minus-side power supply pattern. An auxiliary component having a high resistance and good heat conduction characteristics so as not to affect the operating resistance region of the thermistor is further provided.
5. The charging stand for an electronic device according to claim 4, wherein the auxiliary component is disposed at a position connecting the thermistor and the plus output terminal and a position connecting the thermistor and the minus output terminal.

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