TWI883010B - Receptacle unit for a mobile terminal, system for charging an energy store of a mobile terminal, and method for controlling a switching unit of a receptacle unit for a mobile terminal - Google Patents

Abstract

The invention relates to a receptacle unit (10) for a mobile terminal (12) that has a charging coil (14) for the contactless charging of an energy store (26), wherein the receptacle unit (10) comprises a voltage supply input (16) and a transmission unit (18) for generating a resonant inductive coupling with the charging coil (14), characterized in that the receptacle unit (10) has a switching unit (20) and a receiver unit (22) for generating a resonant inductive coupling with an external charging station (24) for the contactless charging of a mobile terminal (12), wherein the switching unit (20) is electrically connected to the voltage supply input (16), wherein the switching unit (20) electrically connects the transmission unit (18) to the voltage supply input (16) in a first switching state and electrically connects the transmission unit (18) to the receiver unit (22) in a second switching state. The invention provides a receptacle unit (10) that avoids shielding of external magnetic fields and makes it possible to charge the mobile terminal (12) arranged in the receptacle unit (10) by way of an external contactless charger.

Description

Socket unit for mobile terminal, system for charging energy storage device of mobile terminal, and method for controlling switch unit of socket unit for mobile terminal

The present invention relates to a socket unit for a mobile terminal as claimed in claim 1, and to a system for an energy storage device for charging a mobile terminal as claimed in claim 8.

In order to charge the battery of a mobile terminal (e.g. a smartphone), it is possible to use a wireless charging method in which energy is transferred via resonant inductive coupling. In this case, the mobile terminal can have a receiver comprising a coil, with the help of which the mobile terminal can be wirelessly charged by an external charger. The external charger contains a transmitter comprising a coil and is supplied with energy by a voltage source, which is often connected to its USB port. The necessary coils of the receiver built into the mobile terminal and used to receive the magnetic field that transfers the energy are usually located on the rear of the mobile terminal. With regard to ease of use, it is extremely important for a mobile terminal plugged into its socket unit to also be able to be wirelessly charged by an external charger without the charging time being significantly prolonged by the socket unit being in use. This requirement is met when the magnetic field emitted by the external charger is not significantly disturbed by the socket unit. This is the case when the socket unit consists of plastic and does not contain any material that attenuates the magnetic field in the area of the parallel surface covering the coil built into the mobile terminal for the receiver located there.

However, there are application cases where the plastic socket unit itself contains a built-in transmitter including a coil. The transmitter including a coil is built into the socket unit to enable wireless charging of a mobile terminal plugged into the socket unit during a bicycle ride. For this purpose, the mobile terminal has available a specially designed socket unit which receives the operating voltage of the transmitter built into the socket unit from an external device supplied via electrical contacts. In this case, the voltage supply input of the socket unit is connected to the voltage supply output of the external device.

In this case, the coil has a magnetic shielding which shields the coil of the receiver of the mobile terminal from external magnetic fields which are not emitted by the coil of the transmitter in the socket unit. In the case of known socket units, contactless charging of a mobile terminal arranged in the socket unit without an external device having a voltage supply output is thus slowed down.

Therefore, the object of the present invention is to provide a socket unit that avoids shielding of external magnetic fields and makes it possible to charge a mobile terminal arranged in the socket unit by means of an external contactless charger.

The main features of the invention are set forth in claims 1 and 8. The improvements are the subject matter of claims 2 to 7 and this specification.

The present invention relates to a socket unit for a mobile terminal, the mobile terminal having a charging coil for contactless charging of an energy storage device, wherein the socket unit includes a voltage supply input for generating resonant inductive coupling with the charging coil and a transmission unit, wherein the socket unit is provided with a switch unit and a receiver unit for generating resonant inductive coupling with an external charging station for contactless charging of the mobile terminal, wherein the switch unit is electrically connected to the voltage supply input, wherein the switch unit electrically connects the transmission unit to the voltage supply input in a first switching state, and electrically connects the transmission unit to the receiver unit in a second switching state.

The present invention establishes resonant inductive coupling with an external charging station by means of a receiver unit. When a voltage is present at the receiver unit, a switch unit creates a connection with the transmission unit, which establishes a resonant inductive coupling with the charging coil of the mobile terminal. Therefore, it is possible to bypass or bypass the shield by means of the receiver unit, making it possible to perform contactless charging via the transmission coil of the external charger. If the external charger provides voltage via a voltage supply output via electrical contacts, the switch unit can create a connection between the voltage supply input and the transmission unit. The transmission unit is then supplied with voltage via the voltage supply input. Therefore, a socket unit is provided which avoids shielding of an external magnetic field and makes it possible to charge a mobile terminal arranged in the socket unit by means of an external contactless charger.

According to a further improvement, when a voltage higher than a first predetermined threshold value is present at the voltage supply input, the switching unit changes to a first switching state.

The first predetermined threshold value may be, for example, between 2 volts and 12 volts, preferably between 3 volts and 10 volts, and more preferably 5 volts. This avoids very small voltages that cause the switch unit to change to the first switch state. This further enables the switch unit to change to the first switch state when there is sufficient supply voltage at the voltage supply input to charge the mobile terminal in the socket unit.

When a voltage higher than a second predetermined threshold value is present at the receiver unit, the switch unit may further be switched to a second switching state.

The second predetermined threshold value can also be, for example, between 2 volts and 12 volts, preferably between 3 volts and 10 volts, and more preferably 5 volts. This avoids a very small voltage that causes the switch unit to change to the second switch state. This further enables the switch unit to change to the second switch state when the receiver unit provides sufficient voltage (i.e., receives sufficient energy from the external contactless charger) to charge the mobile terminal in the socket unit.

In a specific example, it is further provided that the socket unit has a transmission coil, a receiving coil and a magnetic shielding element connected to the transmission coil, the magnetic shielding element is arranged between the transmission coil and the receiving coil, wherein the transmission coil is electrically connected to the transmission unit and the receiving coil is electrically connected to the receiver unit.

In this case, the transmission coil is arranged between the magnetic shielding element and the mobile terminal. The magnetic shielding element concentrates the magnetic field generated by the transmission coil. This improves the effectiveness of energy transfer to the mobile terminal. The magnetic shielding element further shields the magnetic field emitted by the transmission coil or the emitted electromagnetic radiation in an orientation pointing away from the mobile terminal. The receiving coil is arranged on the other side of the magnetic shielding element pointing away from the mobile terminal. The receiving coil is thereby able to receive energy from the magnetic field generated by the external contactless charger. Therefore, the magnetic shielding element is bypassed or circumvented by the connection between the transmission coil and the receiving coil generated by the switching unit.

In this case, the receiving coil can be connected to the magnetic shielding element.

Therefore, the receiving coil and the transmitting coil use the same magnetic shielding element. The magnetic shielding element concentrates the magnetic field received by the receiving coil and improves the efficiency of energy transfer between the external contactless charger and the receiving coil.

In an alternative embodiment, the socket unit may have a second magnetic shielding element between the receiving coil and the magnetic shielding element, wherein the second magnetic shielding element is connected to the receiving coil.

This avoids the situation where the magnetic shielding element has an extremely thin design and a magnetic short circuit is generated by the magnetic shielding element if there is a strong magnetic field at both the receiving coil and the transmitting coil.

In this case, at least one spacer having low magnetic permeability may be disposed between the magnetic shielding element and the second magnetic shielding element.

Thus, an air gap is created between the two magnetic shielding elements and the likelihood of a magnetic short circuit is reduced. The spacer further reduces this likelihood due to its low magnetic permeability.

The present invention further relates to a system for charging an energy storage device of a mobile terminal, wherein the system has a socket unit as described above and a charging holder for the socket unit, wherein the charging holder has a voltage supply output terminal, wherein the socket unit is arranged in the charging holder and the voltage supply input terminal is electrically connected to the voltage supply output terminal.

Based on the advantages, effects and developments of the socket unit described above, the advantages, effects and developments of the system become apparent. Therefore, reference is made to the above description in this regard.

The present invention further relates to a method for controlling a switch unit of a socket unit for a mobile terminal in one of the above-described aspects, wherein the method comprises the following steps: connecting a transmission unit of the socket unit to a receiver unit of the socket unit when the receiver unit is resonantly inductively coupled with an external charging station; and connecting the transmission unit to a voltage supply input of the socket unit when a supply voltage is present at the voltage supply input.

The advantages and effects and developments of the socket unit described above make the advantages and effects and developments of the method apparent. Therefore, reference is made to the above description in this regard.

The method may further include the following steps: disconnecting the transmission unit from the receiver unit when the receiver unit is not resonantly inductively coupled with the external charging station; and disconnecting the transmission unit from the voltage supply input when there is no supply voltage at the voltage supply input.

10: Socket unit

12:Mobile terminal

14: Charging coil

16: Voltage supply input terminal

18: Transmission unit

20: Switch unit

22: Receiver unit

24: External contactless charger/external charging station

26: Energy storage device

28: Transmission coil

30: Receiving coil

32: Magnetic shielding element

34: Second magnetic shielding element

36: Spacer

38: Shielding element

42: Transmission coil

44: Shielding element

46: Ground terminal

48: DC voltage terminal

50: Ground terminal

52: DC voltage terminal

54: Ground terminal

56: DC voltage terminal

58: Resistor

60: Transistor

62: Transistor

64: Resistor

66: Transistor

68: Transistor

70: Charging holder

72: Shell

74:Handle

76: Voltage supply output terminal

100:Methods

102: Steps

104: Steps

106: Steps

108: Steps

Other features, details and advantages of the invention will become apparent from the wording of the claims and from the following description of exemplary embodiments with reference to the drawings, in which: [FIG. 1] shows a schematic diagram of a socket unit; [FIG. 2] shows a schematic diagram of an exemplary circuit of a switch unit; [FIG. 3a and b] show schematic diagrams of various views of further exemplary embodiments; [FIG. 4a and b] show schematic diagrams of a system and a socket unit; and [FIG. 5] shows a flow chart of a method.

FIG. 1a shows a socket unit 10 disposed between a mobile terminal 12 and an external contactless charger 24. The mobile terminal 12 may be, for example, a smartphone or a tablet computer having a Qi charging function for an energy storage device 26 and may have a charging coil 14 having a shielding element 38. The external contactless charger 24 may be, for example, a Qi charger having a shielding element 44 and a transmission coil 42.

The socket unit 10 may be made of plastic and has a voltage supply input 16 and a transmission unit 18 for generating resonant inductive coupling with a charging coil 14 of a mobile terminal 12. The socket unit 10 further has a switch unit 20 and a receiver unit 22 for generating resonant inductive coupling with an external charging station 24 for contactless charging of the mobile terminal 12.

The socket unit 10 further includes a transmission coil 28, a receiving coil 30, and a magnetic shielding element 32 connected to the transmission coil 28, and the magnetic shielding element 32 is arranged between the transmission coil 28 and the receiving coil 30. In this case, the transmission coil 28 is electrically connected to the transmission unit 18, and the receiving coil 30 is electrically connected to the receiver unit 22. In this exemplary embodiment, the transmission coil 28 and the receiving coil 30 are both connected to the magnetic shielding element 32.

The magnetic shielding element 32 may contain ferrite.

The ground terminals 46, 50, 54 and the DC voltage terminals 48, 52, 56 are connected to the switch unit 20. The ground terminal 50 and the DC voltage terminal 52 connect the switch unit 20 to the transmission unit 18. The ground terminal 54 and the DC voltage terminal 56 connect the switch unit 20 to the voltage supply input 16. The ground terminal 46 and the DC voltage terminal 48 connect the switch unit 20 to the receiver unit 22.

In this case, when the voltage supply input terminal 16 is connected to the voltage supply output terminal of a running external charger, the DC voltage terminal 56 can have a positive DC voltage (e.g., 5V) relative to the ground terminal 54.

In this case, the switch unit 20 electrically connects the transmission unit 18 to the voltage supply input terminal 16 in the first switching state, and the switch unit 20 electrically connects the transmission unit 18 to the receiver unit 22 in the second switching state.

The switch unit 20 makes it possible for its two terminals 50 and 52, which transmit the working voltage of the built-in transmission unit, to be connected or not connected to the terminal 54 or 56 and/or to be connected or not connected to the terminal 46 or 48, wherein the ground terminals 46, 50, 54 are always connected to each other. When the voltage at the DC voltage terminal 48 or 56 has exceeded the first or second predetermined threshold value, the DC voltage terminal 52 is always connected to the DC voltage terminal 48 or 56.

In principle, both DC voltage terminals 48 and 56 can also be connected to the DC voltage terminal 52 at the same time. However, for this purpose, it would be necessary to provide a connection between the voltage supply input 16 and the voltage supply output of the external charger and the transmission coil at the receiving coil 30 at the same time. However, this will not happen at the same time in practice, since an external charger with a voltage supply output and an external contactless charger are mutually exclusive for spatial reasons.

Therefore, the switching logic defined in the switch unit 20 realizes a situation in which the transmission unit 18 embedded in the socket unit 10 is operated using a voltage transmitted from an external charger having a voltage supply output terminal via terminals 54 and 56, or is operated using a voltage transmitted via terminals 46 and 48 by the receiver unit 22 built into the socket unit, wherein the voltage at the terminals 46 and 48 is in turn generated from the magnetic field emitted by the external contactless charger. In this specific example, regardless of whether the original charging energy originates from an external charger having a voltage supply output or from an external contactless charger, the mobile terminal 12 is always wirelessly charged by the built-in transmission unit 18 including its transmission coil 28 connected to the magnetic shielding element 32.

FIG. 2 illustrates by way of example a specific example of a switch unit 20 in the form of an electronic switch with two identical complementary Darlington pairs. Components 62 and 68 are two identical NPN transistors, and components 60 and 66 are two identical PNP transistors. Transistor 62 and transistor 60 or transistor 68 and transistor 66 are connected in a complementary Darlington pair. If the operating voltage for the respective complementary Darlington pair is applied at the DC voltage terminal 56 or 48, the resistor 58 or the resistor 64 ensures that the transistor 60 or the transistor 66 is always in the on state. If there is no operating voltage at the DC voltage terminal 56 or 48 (i.e., if the DC voltage terminal 56 or 48 is floating in a voltage-free manner), the transistor 60 or the transistor 66 is in the off state. The transistor 60 or the transistor 66 in the on state or the off state similarly puts the transistor 62 or the transistor 68 in the on state or the off state. Assume that B1 is the gain factor of the two NPN transistors and B2 is the gain factor of the two PNP transistors. If the resistor 58 or 64 is selected so that a current of Ib2 flows through the base of the transistor 60 or the transistor 66 when the transistor 60 or the transistor 66 is in the on state, a current of approximately Ib2 x B1 x B2 flows through the load connected to the terminals 52 and 50. That is, the current flowing through the load at 52 and 50 is B1 x B2 times Ib2. According to FIG. 3 , since this load is exactly the transmission unit 18, including the transmission coil 28 built into the socket unit 10, the complementary Darlington pair ensures a sufficiently large charging current for the transmission unit 18 built into the socket unit 10. If, for example, a voltage of 5V is applied at the DC voltage terminal 56, the resistor 58 has a value of 10kΩ, and assuming that B1=B2=50, a current of approximately (5V-0.65V)/10kΩ=0.435mA flows through the resistor 58. After being amplified by the transistor 60 and the transistor 62, a current of 1.0875A flows through the load connected to 52 and 50. This current is within the range of typical input currents of a transmission unit 18 designed as, for example, a Qi transmitter. The maximum power consumption of the transmission unit 18 built into the socket unit 10 will therefore be approximately (5V-0.2V) x 1.0875A = 5.22W.

If no operating voltage is applied at the DC voltage terminal 48 or 56, the voltage relative to ground is zero. In this case, since either transistor 68 or transistor 62 is in the off state, the associated complementary Darlington pair has no effect on the other complementary Darlington pair. If operating voltages are applied at both the DC voltage terminal 48 and the DC voltage terminal 56, which operating voltages need not be the same, both transistor 68 and transistor 62 are in the on state. The sum of the collector-emitter currents of transistor 62 and transistor 68 then flows through the load connected to 52 and 50. The two collector-emitter currents automatically adjust themselves so that a possible voltage difference between the DC voltage terminal 56 and the DC voltage terminal 48 is compensated by the different collector-emitter voltages of the transistor 62 and the transistor 68. It is always the case that the voltage at the DC voltage terminal 56 minus the collector-emitter voltage of the transistor 62 is equal to the voltage at the DC voltage terminal 48 minus the collector-emitter voltage of the transistor 68.

Figures 3a and 3b show alternative exemplary embodiments of the configuration of the transmission coil 28, the magnetic shielding element 32, and the receiving coil 30.

The receiving coil 30 is connected to a second magnetic shielding element 34 instead of the magnetic shielding element 32 used for the two coils 20, 30. In this case, the two magnetic shielding elements 32, 34 may contain round ferrite with high magnetic permeability. An air gap is created between the two magnetic shielding elements 32, 34 by means of at least one spacer 36. Since air has a magnetic permeability of approximately 1, its magnetic permeability is much smaller than the two magnetic shielding elements 32, 34, which, when composed of ferrite, have a magnetic permeability between 300 and 300,000. The magnetic flux of the transmission unit 18 and the receiver unit 20 is thus limited to the magnetic shielding element 32 or the second magnetic shielding element 34. The air gap may be created via two magnetic shielding elements 32, 34, which are separated by, for example, three spacers 36 in the middle, as illustrated in FIG3b. The spacers 36 may be composed of a plastic material having a low magnetic permeability.

FIG. 4a illustrates a system for charging an energy storage device 26 of a mobile terminal 12. In this case, the system includes a socket unit 10 and a charging holder 70 for the socket unit 10. The charging holder 70 has a voltage supply output 76, wherein the socket unit 10 is disposed in the charging holder 70, and the voltage supply input 16 is electrically connected to the voltage supply output 76.

For example, the charging holder 70 can be connected to the handlebar 74 of the electric bicycle and the mobile terminal 12 can be fixed thereto. In this case, the voltage supply output 76 can provide the voltage from the control unit of the electric bicycle to charge the mobile terminal 12 in the socket unit 10. In this case, the housing 72 can be provided to protect the mobile terminal 12 from the weather.

By means of the voltage supply input 16 illustrated in more detail in FIG. 4b , the socket unit 10 can be connected to the voltage supply output 76 of the charging holder 70 , which requires a conductive connection in order to transfer energy to the socket unit 10 . In this case, the switch unit 20 is placed in the first switching state.

FIG5 shows a flow chart of a method 100 for controlling a switch unit of a socket unit for a mobile terminal as described above. In this case, the steps 102 to 108 described can be performed in any order that makes logical sense or can be performed simultaneously accordingly.

In step 102, the transmission unit of the socket unit is connected to the receiver unit of the socket unit when the receiver unit is resonantly inductively coupled with the external charging station. .

In step 104, the transmission unit is disconnected from the receiver unit when the receiver unit is not resonantly inductively coupled with the external charging station.

In step 106, when there is a supply voltage at the voltage supply input terminal, the transmission unit is connected to the voltage supply input terminal of the socket unit.

In step 108, when there is no supply voltage at the voltage supply input, the transmission unit is disconnected from the voltage supply input.

10: Socket unit

12:Mobile terminal

14: Charging coil

16: Voltage supply input terminal

18: Transmission unit

20: Switch unit

22: Receiver unit

24: External contactless charger/external charging station

26: Energy storage device

28: Transmission coil

30: Receiving coil

32: Magnetic shielding element

36: Spacer

38: Shielding element

42: Transmission coil

44: Shielding element

46: Ground terminal

48: DC voltage terminal

50: Ground terminal

52: DC voltage terminal

54: Ground terminal

56: DC voltage terminal

Claims (10)

A socket unit for a mobile terminal (12), wherein the mobile terminal (12) has a charging coil (14) for contactless charging of an energy storage device (26), wherein the socket unit (10) includes a voltage supply input terminal (16) and a transmission unit (18) for generating a resonant inductive coupling with the charging coil (14), and is characterized in that the socket unit (10) has a switch unit (20) and a receiver unit (22) for generating a resonant inductive coupling with an external charging station (24) for contactless charging of the mobile terminal (12). , wherein the switch unit (20) is electrically connected to the voltage supply input terminal (16), wherein the switch unit (20) electrically connects the transmission unit (18) to the voltage supply input terminal (16) in a first switch state, and electrically connects the transmission unit (18) to the receiver unit (22) in a second switch state, and wherein the voltage supply input terminal (16) is electrically connected to the voltage supply output terminal (76) of the charging holder (70), the socket unit (10) is disposed in the charging holder (70), and the charging holder (70) is connected to the handle (74). A socket unit as claimed in claim 1, wherein when a voltage higher than a first predetermined threshold value is present at the voltage supply input terminal (16), the switch unit (20) changes to the first switch state. A socket unit as claimed in claim 1 or 2, wherein the switch unit (20) changes to the second switch state when a voltage higher than a second predetermined threshold value is present at the receiver unit (22). A socket unit as claimed in claim 1 or 2, wherein the socket unit (10) has a transmission coil (28), a receiving coil (30) and a magnetic shielding element (32) connected to the transmission coil (28), the magnetic shielding element is arranged between the transmission coil (28) and the receiving coil (30), wherein the transmission coil (28) is electrically connected to the transmission unit (18) and the receiving coil (30) is electrically connected to the receiver unit (22). A socket unit as claimed in claim 4, wherein the receiving coil (30) is connected to the magnetic shielding element (32). A socket unit as claimed in claim 4, wherein the socket unit (10) has a second magnetic shielding element (34) between the receiving coil (30) and the magnetic shielding element (32), wherein the second magnetic shielding element (34) is connected to the receiving coil (30). As in the socket unit of claim 6, at least one spacer (36) having low magnetic permeability is arranged between the magnetic shielding element (32) and the second magnetic shielding element (34). A system for charging an energy storage device (26) of a mobile terminal (12), wherein the system has a socket unit (10) as described in any one of claims 1 to 7 and a charging holder (70) for the socket unit (10), wherein the charging holder (70) has a voltage supply output terminal (76), wherein the socket unit (10) is arranged in the charging holder (70), and the voltage supply input terminal (16) is electrically connected to the voltage supply output terminal (76), and the charging holder (70) is connected to a handle (74). A method for controlling a switch unit of a socket unit for a mobile terminal as in any one of claims 1 to 7, wherein the method (100) comprises the following steps: connecting (102) a transmission unit of the socket unit to a receiver unit of the socket unit when a receiver unit is resonantly inductively coupled with an external charging station; and connecting (106) a transmission unit to a voltage supply input of the socket unit when a supply voltage is present at the voltage supply input. The method of claim 9, wherein the method (100) further comprises the following steps: disconnecting the transmission unit from the receiver unit (104) when the receiver unit is not resonantly inductively coupled with an external charging station; and disconnecting the transmission unit from the voltage supply input terminal (108) when there is no supply voltage at the voltage supply input terminal.

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