Remote control

Abstract

A remote control (100) relating to remote control operation, comprising: a lithium-ion battery (111); an infrared signal transmission unit (102) and a resistor (101) connected in parallel to the lithium-ion battery (111), wherein the resistor (101) is a first resistor connected in series with the infrared signal transmission unit (102); a micro (105) as a microcomputer that controls a transmission of an infrared signal through the infrared signal transmission unit (102) and is connected in parallel to the lithium-ion battery (111); and several capacitors (106 to 110) connected in parallel to the micro (105) and comprising at least two ceramic capacitors.

Description

Technical area

[0001] The present disclosure relates to a remote control which uses a lithium-ion battery. Technological background

[0002] When operating a device such as an air conditioner, users employ a connected remote control (hereinafter referred to as the remote) or other device to set a desired temperature and other settings. In the remote, an input unit, such as buttons, receives user input, and in response to the user input, a control unit, such as a microcomputer (hereinafter referred to as the micro), causes an infrared light-emitting diode (LED) to emit light to transmit an infrared signal to the device, such as the air conditioner, thus controlling its operation. Some remotes contain internal electrolytic capacitors to stabilize the power supply, maintaining an internal voltage supplied to the micro by batteries.Patent literature 1, for example, discloses a technique which inhibits the generation of heat as a result of a short-circuit current in a remote control even when an electrolytic capacitor is short-circuited to stabilize the power supply. Citation listPatent literature

[0003] Patent literature 1: Japanese patent application publication number 2000 - 316 193 Brief description of the inventionProblem to be solved by the invention

[0004] A lithium-ion battery is used as the power source in the remote control. Due to aging caused by exposure to air, the internal resistance of the lithium-ion battery increases. In a remote control circuit that uses a lithium-ion battery, a current-limiting resistor and a transistor (or similar component) are connected in series with the infrared LED. The control unit, such as the Micro, regulates the current flow to the infrared LED by switching the transistor on and off, thereby controlling the transmission of the infrared signal.The Micro is typically equipped with a bypass capacitor of approximately 0.1 µF, such as that used in an integrated circuit (IC) or similar device, and an electrolytic capacitor of approximately 10 µF to 47 µF or similar, as required for power supply stabilization, with these capacitors connected in parallel to the lithium-ion battery. In a small remote control using a lithium-ion battery, limited mounting space and cost considerations are some of the reasons why redundant capacitors and higher-capacity capacitors are typically not included.

[0005] If the remote control with such a design is powered by a lithium-ion battery with increased internal resistance, the current flowing to the infrared LED also flows through the internal resistance of the lithium-ion battery. This leads to a decrease in the supply voltage provided by the lithium-ion battery, which is, in effect, the remote control's internal power supply voltage. Therefore, a problem arises with the remote control: if the internal power supply voltage falls below the microcontroller's reset voltage, the microcontroller is reset, causing the infrared signal to no longer be transmitted.

[0006] The present disclosure was made in light of the foregoing, and it is an object of the present disclosure to obtain a remote control capable of avoiding interruption of an infrared signal transmission even when a lithium-ion battery has an increased internal resistance. Means to solve the problem

[0007] To solve the aforementioned problems and to fulfill the task, a remote control according to the present disclosure comprises: a lithium-ion battery; an infrared signal transmission unit and a first resistor connected in parallel to the lithium-ion battery, the first resistor being connected in series with the infrared signal transmission unit; a microcomputer for controlling the transmission of an infrared signal through the infrared signal transmission unit, the microcomputer being connected in parallel to the lithium-ion battery; and several capacitors connected in parallel to the microcomputer, and at least two ceramic capacitors. Effects of the invention

[0008] The remote control according to the present disclosure has the effect of preventing an interruption of an infrared signal transmission even when the lithium-ion battery has an increased internal resistance. Short description of the drawings Fig. Figure 1 is a diagram that represents an exemplary configuration of a remote control according to a first embodiment. Fig. Figure 2 is a diagram that shows an exemplary configuration of a remote control according to a second embodiment. Fig. Figure 3 is a diagram which shows an example of a data frame of an infrared signal to be transmitted by an infrared signal transmission unit of the remote control according to the second embodiment. Description of embodiments

[0009] The following is a detailed description of remote control systems according to the embodiments of the present disclosure, with reference to the drawings. First embodiment

[0010] Fig. Figure 1 is a diagram illustrating an exemplary configuration of a remote control 100 according to a first embodiment. The remote control 100 comprises a resistor 101, an infrared signal transmission unit 102, a transistor 103, a resistor 104, a microcomputer 105, capacitors 106 to 110, and a lithium-ion battery 111. The remote control 100 is used to operate a device such as an air conditioner (not shown).

[0011] Resistor 101 is a current-limiting resistor connected in series with the infrared signal transmission unit 102. In the following description, resistor 101 can be referred to as the first resistor.

[0012] The infrared signal transmission unit 102 transmits infrared signals under the control of the Micro 105. The infrared signal transmission unit 102 is, for example, an infrared LED and emits infrared light when driven by the transistor 103, thus transmitting an infrared signal.

[0013] Transistor 103 is connected in series with infrared signal transmission unit 102 and is switched ON and OFF under the control of Micro 105 to regulate the conductivity of infrared signal transmission unit 102. Resistor 101, infrared signal transmission unit 102, and transistor 103 are connected in parallel to lithium-ion battery 111.

[0014] Resistor 104 is a current-limiting resistor connected in series with Micro 105. Resistor 104 is connected between the lithium-ion battery 111, Micro 105, and capacitors 106 to 110. In the following description, resistor 104 can be referred to as the second resistor.

[0015] The Micro 105 is a microcomputer that controls the transmission of infrared signals via the infrared signal transmission unit 102. Specifically, the Micro 105 receives user input from an input unit (not shown) and performs the ON / OFF control of transistor 113 to transmit an infrared signal corresponding to the content of the user input. Resistor 104 and the Micro 105 are connected in parallel with the lithium-ion battery 111.

[0016] Capacitor 106 is connected between a power supply and ground for the Micro 105 (hereinafter referred to as GND) and is a bypass capacitor with a capacitance of approximately 0.1 µF, as recommended for an IC, or similar component, such as the Micro 105. Capacitor 106 is, for example, a ceramic capacitor.

[0017] The capacitor 107 is connected between the power supply and GND for the Micro 105 and is an electrolytic capacitor for stabilizing the power supply, which has a capacitance of approximately 10 µF to 47 µF for stabilizing the power supply inside the remote control 100.

[0018] Capacitors 108 to 110 are connected between the power supply and GND for the Micro 105 and are ceramic capacitors of higher capacitance, which maintain an internal power supply voltage for the remote control 100 until the infrared signal transmission by the remote control 100 is complete. While the remote control 100 in the example of Fig. The fact that the remote control 100 has capacitors 108 to 110, namely three ceramic capacitors, is not limiting. Depending on the required capacitance, as described below, the number of ceramic capacitors in the remote control 100 can be two or fewer, or four or more. Assuming the presence of capacitor 106, the remote control 100 must have at least two ceramic capacitors. In other words, the remote control 100 has several capacitors, including at least two ceramic capacitors, in the form of capacitors 106 to 110 connected in parallel to the microcontroller 105.

[0019] The lithium-ion battery 111 is a battery that provides the power supply voltage to the internal components of the remote control 100. As previously noted, the lithium-ion battery 111 typically experiences an increasing internal resistance due to aging caused by exposure to the air.

[0020] The combined capacitance of capacitors 106 to 110, for which a calculation method is described below, must be 200 µF or more. Generally, the remote control 100, which uses the lithium-ion battery 111, is often small, and space for mounting components is frequently limited. Therefore, the remote control 100 uses high-capacity ceramic capacitors, introduced in recent years, as capacitors 108 to 110 with higher capacitance, which maintain the internal power supply voltage for the remote control 100. Of the ceramic capacitors used as capacitors 108 to 110, those with a capacitance of 220 µF each currently represent the largest class in terms of a balanced cost-to-size ratio.Therefore, in the configuration of the remote control 100, the use of two or three 220-µF ceramic capacitors, depending on the required capacitance, is effective in solving the problem, specifically in maintaining the internal power supply voltage of the remote control 100.

[0021] In the remote control 100, current is supplied to the infrared signal transmission unit 102 from capacitors 108 to 110, which are high-capacity ceramic capacitors. However, there is a concern that too much current may flow from capacitors 108 to 110 to the infrared signal transmission unit 102. If too much current flows to the infrared signal transmission unit 102, it may not be able to transmit an infrared signal for an extended period of time. Therefore, according to the present embodiment, the remote control 100 includes the current-limiting resistor 104, which is connected in series on one power supply side of the micro 105 to allow an electrical discharge to be maintained while the infrared signal transmission unit 102 transmits the infrared signal.

[0022] With a suitable balance of the capacitances of capacitors 108 to 110, which are ceramic capacitors, and a specific resistance value for resistor 104, the remote control 100 is able to maintain the power supply voltage while the infrared signal transmission unit 102 transmits the infrared signal. Since resistor 104 is connected in series between the lithium-ion battery 111 and the microcontroller 105, the voltage supplied to the microcontroller 105 can decrease when current flows to it. Therefore, a resistor with a higher resistance value than resistor 104 is typically not selected.Regarding the resistance value of resistor 104, an empirically chosen resistance value is approximately 10 Ω; however, in the present embodiment, depending on a balance with the combined capacitance of capacitors 106 to 110, a resistance value of 20 Ω or more may be preferably selected to prevent the capacitance of capacitors 106 to 110 from becoming too large.

[0023] A detailed description of the constants of the circuit elements of the remote control 100 is given. The voltage supplied to the microcontroller 105 when current flows to the infrared signal transmission unit 102 in the remote control 100 is determined by the resistance of resistor 101, the resistance of resistor 104, the combined capacitance of capacitors 106 to 110, and the internal resistance of the lithium-ion battery 111. Resistor 101 is selected to have a resistance value that ensures the required transmission distance of an infrared signal from the infrared signal transmission unit 102 and satisfies the maximum design capacity of the lithium-ion battery 111 when the lithium-ion battery 111 is used in a normal, undamaged condition, meaning it does not have an increased internal resistance.The constants of the capacitors 106 to 110, the resistor 101 and the resistor 104 used in the remote control 100 satisfy a requirement defined by the following formula (1). C>−t / (R×ln(V1 / V0))

[0024] In equation (1), C represents the combined capacitance of capacitors 106 to 110. R represents the combined resistance of resistors 102 and 104. V0 represents the reset voltage of the microcontroller 105. V1 represents the supply voltage provided by the lithium-ion battery 111. t represents the total time during which the infrared signal is actually transmitted by the remote control 100, specifically by the infrared signal transmission unit 102. t can also be considered the total time during which the infrared signal transmission unit 102 is driven by transistor 103.

[0025] For example, it is assumed that the internal resistance of lithium-ion battery 111 has increased to approximately 300 Ω. The current draw from lithium-ion battery 111 is less than 1 / 10 compared to when the internal resistance of lithium-ion battery 111 is small, and can therefore be estimated almost exactly using formula (1). When calculated using formula (1), the combined capacitance of capacitors 106 to 110 is practically 200 µF or more, the resistance of resistor 101 is approximately 10 to 20 Ω, and the resistance of resistor 104 is 20 Ω or more. By using the capacitors 106 to 110 and the resistors 101 and 104, which have the aforementioned constants, the remote control 100 enables the transmission of the infrared signal through the infrared signal transmission unit 102 to continue even when there is an increase in the internal resistance of the lithium-ion battery 111.The above constants are also effective experimentally by enabling the remote control 100 to avoid the internal power supply voltage of the remote control 100 becoming the reset voltage of the micro 105 until the infrared signal transmission unit 102 completes the transmission of the infrared signal.

[0026] As described above, the remote control 100, according to the present embodiment, is equipped between the power supply and GND for the Micro 105 with capacitors 108 to 110, which are high-capacity ceramic capacitors that are not usually installed in a small remote control due to space constraints. Furthermore, the remote control 100 uses capacitors 106 to 110 and resistors 101 and 104, which have adapted constants, to prevent the internal power supply voltage of the remote control 100 from reaching or falling below the reset voltage of the Micro 105, even if the internal resistance of the lithium-ion battery 111 increases.Therefore, even if the internal resistance value of the lithium-ion battery 111 increases, the Micro 105 is prevented from being reset, which allows the remote control 100 to avoid an interruption of the infrared signal transmission and to continue transmitting the infrared signal. Second embodiment

[0027] In a second embodiment, a description is given of a case in which a microcomputer is equipped with a voltage monitoring port.

[0028] Fig. Figure 2 is a diagram illustrating an exemplary configuration of a remote control 100a according to the second embodiment. The remote control 100a comprises, compared to the one in Fig. The remote control 100 shown in Figure 1 uses the microcomputer 105a instead of the Micro 105. The Micro 105a includes the voltage monitoring port 112. The voltage monitoring port 112 uses an analog-to-digital (AD) conversion function of the Micro 105a and monitors a power supply voltage provided by the lithium-ion battery 111, as shown in Figure 1. Fig. 2 is shown.

[0029] When the lithium-ion battery 111 reaches an increased internal resistance value, a current flow to the infrared signal transmission unit 102 involves a greater voltage drop across the lithium-ion battery 111 in the remote control 100a. This is calculated using the following formula (2). V=Vb−Iled1×Rb

[0030] In equation (2), V represents the voltage monitored or detected by the voltage monitoring port 112. Vb represents the supply voltage provided by the lithium-ion battery 111. Iled1 represents the current flowing to the infrared signal transmission unit 102. Rb represents the internal resistance value of the lithium-ion battery 111.

[0031] The Micro 105a can use formula (2) to determine the difference between the voltage monitored by voltage monitoring port 112 during current flow to the infrared signal transmission unit 102 and the voltage monitored by voltage monitoring port 112 when current is not flowing to the infrared signal transmission unit 102. If the difference is greater than or equal to a predefined threshold, the Micro 105a can determine that the internal resistance of the lithium-ion battery 111 has increased. Therefore, after detecting the increased internal resistance of the lithium-ion battery 111 as a result of monitoring by voltage monitoring port 112 during transmission of an infrared signal by the infrared signal transmission unit 102, the Micro 105a adjusts the length of the infrared signal to be transmitted by the infrared signal transmission unit 102.

[0032] In other words, the Micro 105a detects the internal resistance of the lithium-ion battery 111 based on a deviation detected by the voltage monitoring port 112 in the supply voltage provided by the lithium-ion battery 111. Depending on the detected resistance value, the Micro 105a adjusts the transmission pattern of the infrared signal to be transmitted by the infrared signal transmission unit 102. The Micro 105a can determine the internal resistance of the lithium-ion battery 111 not only when a user-input-based infrared signal is transmitted by the infrared signal transmission unit 102, but also when an infrared signal is transmitted by the infrared signal transmission unit 102 in a test pattern before the infrared signal transmission unit 102 transmits a user-input-based infrared signal.

[0033] Fig. Figure 3 is a diagram that shows an example of a data frame of an infrared signal to be transmitted by the infrared signal transmission unit 102 of the remote control 100a according to the second embodiment. On a top side of Fig. Figure 3 shows a diagram of the data frame of an infrared signal to be transmitted by the infrared signal transmission unit 102, and which represents a dummy frame 401, a transmission prohibition interval 402, and a main frame 403. A diagram on a lower side of Fig. Figure 3 represents actual data bits 404 within the main frame 403 and bit lengths 405 per bit. As in Fig. As shown in Figure 3, when the remote control 100a transmits the infrared signal from the infrared signal transmission unit 102, depending on a model, first transmits the dummy frame 401 for a predetermined time to stabilize the receiving capability of a light-receiving element of a device receiving the infrared signal, and after the transmission prohibition interval 402, it transmits the main frame 403, which contains the actual transmission data.

[0034] By stabilizing the receiving capability of the light-receiving element of the device that receives the infrared signal, through the transmission of the dummy frame 401, the remote control 100a enables an extended transmission distance for the infrared signal, particularly for the main frame 403. On the other hand, a drop in the supply voltage to the reset voltage of the micro 105a or below, due to an increased internal resistance of the lithium-ion battery 111 when supplied to the micro 105a, can cause the remote control 100a to interrupt the transmission of the infrared signal midway through. In such a case, the remote control 100a must prioritize the completion of the infrared signal transmission over extending the transmission distance. Accordingly, the remote control 100a does not transmit the dummy frame 401.In this way, the remote control 100a can reduce the transmission time (operating time) of the infrared signal transmission unit 102. Since the time required for the power supply from the lithium-ion battery 111 to the capacitors 106 to 110 also increases, the remote control 100a is able to prevent the supply voltage from reaching or falling below the reset voltage when it is supplied to the microcontroller 105a. In this case, the microcontroller 105a determines, based on the detected internal resistance value of the lithium-ion battery 111, whether or not the dummy frame 401 is to be transmitted in the transmission pattern of the infrared signal to be transmitted by the infrared signal transmission unit 102.

[0035] As in Fig. As shown in Figure 3, the data bits 404 are contained in the main frame 403, and due to standards, there is a predetermined range for the bit length 405 of each of the data bits 404. Normally, the remote control 100a often transmits an infrared signal with a bit length of 405, which is set to a median value of the predetermined range to stabilize the receiving capability of the light-receiving element of the device receiving the infrared signal. In the present embodiment, when transmitting the infrared signal, the remote control 100a changes the ON-time bit length 405 to a value closer to a lower limit of the predetermined range and further changes the OFF-time bit length 405 to a value closer to an upper limit of the predetermined range, thereby enabling a reduced overall ON time and an increased overall OFF time during the transmission of the main frame 403.The AN time is a period during which data bit 404 is stored. Fig. 3 presents a HIGH state, in which there is actually infrared light emission from the infrared signal transmission unit 102. The OFF time is a period during which data bit 404 is in Fig. 3 represents a LOW state in which there is no infrared light emission from the infrared signal transmission unit 102. In this way, the remote control 100a can reduce the transmission time of the infrared signal transmission unit 102. Since the time for the power supply from the lithium-ion battery 111 to the capacitors 106 to 110 also increases, the remote control 100a can prevent the power supply voltage from reaching or falling below the reset voltage when it is applied to the Micro 105a.

[0036] As described above, the Micro 105a monitors the voltage using the voltage monitoring port 112 and performs operations such as not transmitting the dummy frame 401 and changing the bit lengths 405 of the ON-time and OFF-time data bits 404 to allow a further reduction in the capacitance of capacitors 106 to 110. Therefore, in addition to preventing the Micro 105 from being reset, the remote control 100a also reduces the cost of capacitors 106 to 110.For the transmission pattern of the infrared signal to be transmitted by the infrared signal transmission unit 102, the Micro 105a reduces the bit length 405 of the ON-time data bit 404 of the transmission data, increases the bit length 405 of the OFF-time data bit 404 of the transmission data, depending on the detected internal resistance value of the lithium-ion battery 111, or reduces both the bit length 405 of the ON-time data bit 404 of the transmission data and increases the bit length 405 of the OFF-time data bit 404 of the transmission data.

[0037] As described above, the Micro 105a of the remote control 100a, according to the present embodiment, is equipped with the voltage monitoring port 112. The Micro 105a detects an internal resistance value of the lithium-ion battery 111 based on a variation detected by the voltage monitoring port 112 in the supply voltage provided by the lithium-ion battery 111. Depending on the detected resistance value, the Micro 105a adjusts the transmission pattern of an infrared signal to be transmitted by the infrared signal transmission unit 102. In this way, the remote control 100a allows the infrared signal transmission unit 102 to transmit the infrared signal by actual light emission, thus reducing the power consumption within the remote control 100a.As a result, the 100a remote control can even be operated with a lower power supply voltage, and infrared signals can even be transmitted with a lower remaining battery level of the 111 lithium-ion battery, resulting in an extended battery life.

[0038] The configurations described above are exemplary and can be combined with other well-known technologies, and can be partially omitted or modified without altering their essential meaning. The embodiments can be combined with one another. List of reference symbols 100, 100a remote control; 101, 104 resistance; 102 Infrared signal transmission unit; 103 Transistor; 105, 105a microcomputer; 106 capacitor (bypass capacitor); 107 Capacitor (electrolytic capacitor for stabilizing the power supply); 108 to 110 Capacitor (ceramic capacitor); 111 Lithium-ion battery; 112 Voltage monitoring port; 401 Dummy Frame; 402 Transmission prohibition interval; 403 Main-Frame; 404 data bits; 405 bit length. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2000 - 316 193

[0003]

Claims

[1] Remote control, comprising: a lithium-ion battery; an infrared signal transmission unit and a first resistor connected in parallel to the lithium-ion battery, the first resistor being connected in series to the infrared signal transmission unit; a microcomputer for controlling transmission of an infrared signal by the infrared signal transmission unit, the microcomputer being connected in parallel to the lithium-ion battery; and a plurality of capacitors connected in parallel to the microcomputer and comprising at least two ceramic capacitors. [2] Remote control according to claim 1, comprising: a second resistor connected between the lithium-ion battery and the microcomputer and the multiple capacitors. [3] The remote control according to claim 2, wherein the plurality of capacitors have a combined capacitance of at least 200 µF, and the second resistor has a resistance value of at least 20 Ω. [4] Remote control according to claim 2 or 3, wherein the plurality of capacitors, the first resistor, and the second resistor used have constants that satisfy a requirement defined by the following formula: C>−t / (R×ln(V1 / V0)), where C represents a combined capacitance of the multiple capacitors, R represents a combined resistance of the first resistor and the second resistor, V0 represents a reset voltage of the microcomputer, V1 represents a power supply voltage provided by the lithium-ion battery, and t represents a total time of transmission of the infrared signal by the infrared signal transmission unit. [5] The remote control device according to any one of claims 1 to 4, wherein the microcomputer includes a voltage detection port, detects an internal resistance value of the lithium-ion battery based on a change in the power supply voltage supplied by the lithium-ion battery detected by the voltage detection port, and adjusts a transmission pattern of the infrared signal to be transmitted from the infrared signal transmission unit depending on the detected resistance value. [6] The remote control device according to claim 5, wherein the microcomputer detects an internal resistance value of the lithium-ion battery when or before the infrared signal is transmitted by the infrared signal transmission unit based on a user input, and determines whether or not to transmit a dummy frame in a transmission pattern of the infrared signal to be transmitted from the infrared signal transmission unit depending on the detected resistance value. [7] Remote control according to claim 5, wherein the microcomputer detects an internal resistance value of the lithium-ion battery when or before the infrared signal is transmitted by the infrared signal transmission unit based on a user input, and the microcomputer determines a transmission pattern of the infrared signal to be transmitted by the infrared signal transmission unit depending on the detected resistance value of one of Reducing a bit length of an ON-time data bit of transmission data, Increasing a bit length of an OFF-time data bit of transmission data, and both reducing a bit length of an ON-time data bit of transmission data and increasing a bit length of an OFF-time data bit of transmission data carries out.

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