Patent Description:
<CIT> (Patent Document <NUM>) discloses an example of a feeding device (a feeding system) conformable to Universal Serial Bus (USB) standards. This feeding device is a feeding device for vehicle or automobile use.

As shown in <FIG>, a feeding device <NUM> disclosed in Patent document <NUM> is provided with an in-vehicle device (a feeding unit) <NUM> and an open-to-user portion (a connector unit) <NUM>. The in-vehicle device <NUM> and the open-to-user portion <NUM> are connected to each other with a cable <NUM>.

An installation position of the in-vehicle device <NUM> in a vehicle (not shown) and an installation position of the open-to-user portion <NUM> in the vehicle depend on a structure of the vehicle. Accordingly, it is highly possible that a distance between the in-vehicle device <NUM> and the open-to-user portion <NUM>, or a length of the cable <NUM>, varies from one type of vehicle to another type of vehicle. This means that there is a possibility that a voltage supplied to the open-to-user portion <NUM> varies from one type of vehicle to another type of vehicle. Patent Document <NUM> further discloses a voltage adjusting method for supplying a predetermined voltage to the open-to-user portion <NUM> without depending on the length of the cable <NUM>.

The voltage adjusting method of Patent Document <NUM> detects a voltage supplied to the open-to-user portion <NUM> and adjusts an output voltage adjustment resistance in the in-vehicle device <NUM> according to the detection results. This method has a problem which needs a complicated structure in the feeding device <NUM> and causes an increase of a cost of the feeding device <NUM>. Accordingly, there is a demand for a feeding system which can supply a predetermined voltage from a feeding unit to a connector unit with a simpler structure.

It is an object of the present invention to provide a connection method which can supply a predetermined voltage from a feeding unit to a connector unit with a simpler structure. In addition, it is another object of the present invention to provide a feeding system employing such a connection method and to provide a feeding unit and a connector unit which are used in the feeding system.

The above mentioned objects are achieved by a connection method according to claim <NUM>, a feeding system according to claim <NUM>, and a feeding unit according to claim <NUM>.

The connection method of the present invention changes the number of parallel lines included in the connection between the feeding unit and the connector unit according to the length of the connection to adjust a voltage drop between the feeding unit and the connector. In this way, the predetermined voltage can be supplied to the connector unit regardless of the length of the connection between the feeding unit and the connector unit.

The connection method of the present invention may be applied to at least one of the connection between the power port of the feeding unit and the power port of the connector unit and the connection between the ground port of the feeding unit and the ground port of the connector unit. In addition, the connection method of the present invention may be applied to at least a partial section of the connection between the feeding unit and the connector unit. In this way, the voltage drop between the feeding unit and the connector unit can be adjusted at relatively small steps.

If a cross-sectional area (or a diameter) of a line included in a cable connecting the feeding unit and the connector unit is changed, it is possible to adjust the voltage drop between the feeding unit and the connector unit. However, though increasing the diameter of the line included in the cable reduces the electric resistance of the line, it might cause inconvenience, such as deterioration of flexibility of the line, on wiring. In contrast, the present invention selectively combines the lines at least in the partial section of the lines so that the electric resistance or voltage drop between the feeding unit and the connector unit can be adjusted according to the distance between the feeding unit and the connector unit without reducing the flexibility of the lines.

An appreciation of the objectives of the present invention and a more complete understanding of its structure may be had by studying the following description of the preferred embodiment and by referring to the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the scope of the present invention as defined by the appended claims.

Referring to <FIG>, a feeding system <NUM> according to a first embodiment of the present invention is provided with a feeding unit <NUM> and a connector unit <NUM>. The feeding unit <NUM> and the connector unit <NUM> are connected to each other through a first cable (a connection member) <NUM>.

As shown in <FIG>, the feeding unit <NUM> has an input portion <NUM>, a power circuit <NUM> and an output portion <NUM>.

As shown in <FIG>, the input portion <NUM> of the feeding unit <NUM> is provided with a power terminal <NUM> and a ground terminal <NUM>. An outer power supply (not shown) which supplies a predetermined input voltage is connected to the power terminal <NUM> and the ground terminal <NUM>.

As shown in <FIG>, the output portion <NUM> of the feeding unit <NUM> is provided with three or more specific ports <NUM> and a communication port <NUM>. The specific ports <NUM> consist of one or more power supply ports <NUM> and one or more ground ports <NUM>. Here, at least one of the number of the power supply port(s) <NUM> and the number of the ground port(s) <NUM> is a plural number. In the present embodiment, each of the number of the power supply ports <NUM> and the number of the ground ports <NUM> is three. However, the present invention is not limited thereto. At least one of the number of the power supply port(s) <NUM> and the number of the ground port(s) <NUM> should be a plural number, and the number of the power supply port(s) <NUM> and the number of the ground port(s) <NUM> may be different from each other. Moreover, in the present invention, the communication port <NUM> is not essential.

As shown in <FIG>, the plural ports which are included in the specific ports <NUM> and which have the same functions are connected to one another in the feeding unit <NUM>. In other words, the three power supply ports <NUM> are connected to one another in the feeding unit <NUM>, and the three ground ports <NUM> are connected to one another in the feeding unit <NUM>. With this structure, the three power supply ports <NUM> are given with the same output voltages from the power circuit <NUM>. Moreover, the three ground ports <NUM> are given with the same reference voltages (GND).

As shown in <FIG>, the power circuit <NUM> is connected between the input portion <NUM> and the output portion <NUM>. In the present embodiment, the power circuit <NUM> is connected, in the feeding unit <NUM>, to the power terminal <NUM> of the input portion <NUM>, to the power supply ports <NUM> of the output portion <NUM> and to the communication port <NUM> of the output portion <NUM>. The power circuit <NUM> voltage-converts an input voltage inputted to the input portion <NUM> to a converted voltage and supplies the converted voltage to the output portion <NUM> as an output voltage.

In the present embodiment, the power circuit <NUM> includes a voltage conversion and power supply circuit (not shown) conformable to Universal Serial Bus Power Delivery (USB PD) standards. In this case, the power circuit <NUM> carries out the voltage conversion according to information obtained from a user device (not shown) through the connector unit <NUM>, the first cable <NUM> and the communication port <NUM>. In the present embodiment, the communication port <NUM> is used for carrying out communication conformable to the USB PD standards. However, the present invention is not limited thereto. The power circuit <NUM> may not be conformable to the USB PD standards. In that case, the communication port <NUM> may be unnecessary. At any rate, the power circuit <NUM> produces one predetermined voltage or selectively outputs one of plural predetermined voltages. Additionally, structure of the power circuit <NUM> is not related to the present invention directly, and therefore the detailed description thereof will be omitted.

As shown in <FIG>, the connector unit <NUM> is provided with an input portion <NUM> and a connector <NUM> to which the user device (not shown) is connected. The connector <NUM> is a connector conformable to USB Type-C standards, for example. In the present embodiment, the connector <NUM> has at least a power supply terminal <NUM>, a ground terminal <NUM> and a communication terminal <NUM>. However, the present invention is not limited thereto. The connector <NUM> may not be conformable to the USB Type-C standards. Nevertheless, in that case, the connector <NUM> must correspond to the power circuit <NUM> of the feeding unit <NUM>.

As understood from <FIG>, the input portion <NUM> of the connector unit <NUM> is formed to be the same as the output portion <NUM> of the feeding unit <NUM>. In detail, the input portion <NUM> is provided with three or more specific ports <NUM> and a communication port <NUM>. The specific ports <NUM> consist of one or more power supply ports <NUM> and one or more ground ports <NUM>. Moreover, at least one of the number of the power supply port(s) <NUM> and the number of the ground port(s) <NUM> is a plural number. In the present embodiment, each of the number of the power supply ports <NUM> and the number of the ground ports <NUM> is three. The power supply ports <NUM> are connected to one another in the connector unit <NUM>, and the ground ports <NUM> are connected to one another in the connector unit <NUM>. Moreover, the power supply ports <NUM>, the ground ports <NUM> and the communication port <NUM> are connected to the connector <NUM> in the connector unit <NUM>. In detail, the power supply ports <NUM> are connected to the power supply terminal <NUM> of the connector <NUM>, the ground ports <NUM> are connected to the ground terminal <NUM> of the connector <NUM>, and the communication port <NUM> is connected to the communication terminal <NUM> of the connector <NUM>.

In <FIG>, the first cable <NUM> has one power supply connection line (a power supply port connection member) <NUM>, one ground connection line (a ground port connection member) <NUM> and one communication connection line (a communication port connection member) <NUM>. Electrical characteristics of the power supply connection line <NUM> and electrical characteristics of the ground connection line <NUM> may be or not may be the same as each other. Moreover, electrical characteristics of the communication connection line <NUM> may be the same as the electrical characteristics of the power supply connection line <NUM> or the electrical characteristics of the ground connection line <NUM> or may not be the same as the electrical characteristics of the power supply connection line <NUM> or the electrical characteristics of the ground connection line <NUM>.

As shown in <FIG>, the communication connection line <NUM> connects the communication port <NUM> of the output portion <NUM> of the feeding unit <NUM> and the communication port <NUM> of the input portion <NUM> of the connector unit <NUM> to each other. Moreover, the power supply connection line <NUM> connects one of the power supply ports <NUM> of the output portion <NUM> of the feeding unit <NUM> and one of the power supply ports <NUM> of the input portion <NUM> of the connector unit <NUM> to each other. Furthermore, the ground connection line <NUM> connects one of the ground ports <NUM> of the output portion <NUM> of the feeding unit <NUM> and one of the ground ports <NUM> of the input portion <NUM> of the connector unit <NUM> to each other.

As understood from <FIG>, an output voltage generated by the power circuit <NUM> of the feeding unit <NUM> is supplied to the connector unit <NUM> through the first cable <NUM>. At this time, according to an electric resistance of the first cable <NUM>, a voltage drop is caused. In other words, according to a length of the first cable <NUM>, a voltage supplied to the connector unit <NUM> is changed. In order to set the voltage supplied to the connector unit <NUM> from the feeding unit <NUM> to a predetermined value, the present embodiment uses the first cable <NUM> or any of other cables described below according to a distance between the feeding unit <NUM> and the connector unit <NUM>.

Referring to <FIG>, a feeding system 10A has a second cable (a connection member) 40A different from the first cable <NUM> of the feeding system <NUM> of <FIG>. A feeding unit <NUM> and a connector unit <NUM> in the feeding system 10A are the same things as the feeding unit <NUM> and the connector unit <NUM> of <FIG>, respectively.

As shown in <FIG>, the second cable 40A has two power supply lines (power supply port connection members) <NUM>, one ground connection line (ground port connection member) <NUM> and one communication connection line (communication port connection member) <NUM>. Each of the power supply connection lines <NUM>, the ground connection line <NUM> and the communication connection line <NUM> are the same things as the power supply connection line <NUM>, the ground connection line <NUM> and the communication connection line <NUM>, respectively. In the present embodiment, the two power supply connection lines <NUM> have the same electrical characteristics as each other. However, the present invention is not limited thereto. The power supply connection lines <NUM> may have electrical characteristics different from each other.

As shown in <FIG>, each of the power supply connection lines <NUM> connects one of the power supply ports <NUM> of the feeding unit <NUM> and one of the power supply ports <NUM> of the connector unit <NUM> to each other. Here, the power supply ports <NUM> of the feeding unit <NUM> are connected to one another, and the power supply ports <NUM> of the connector unit <NUM> are connected to one another. Accordingly, the two power supply connection lines <NUM> form parallel lines which are connected to each other in parallel.

As understood from <FIG>, a voltage drop per unit length of the second cable 40A in the feeding system 10A of <FIG> is smaller than a voltage drop per unit length of the first cable <NUM> in the feeding system <NUM> of <FIG>. Accordingly, even when a length of the second cable 40A is longer than the length of the first cable <NUM>, an electric resistance or a voltage drop between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM> in the feeding system 10A of <FIG> can be adjusted to the same level as an electric resistance or a voltage drop of the feeding system <NUM>. Therefore, the feeding system 10A can supply a predetermined voltage to the connector unit <NUM> by using the second cable 40A.

Referring to <FIG>, a feeding system 10B has a third cable 40B which is different from the first cable <NUM> of the feeding system <NUM> of <FIG> and the second cable 40A of the feeding system 10A of <FIG>. A feeding unit <NUM> and a connector unit <NUM> in the feeding system 10B are the same things as the feeding unit <NUM> and the connector unit <NUM> of <FIG>, respectively.

As shown in <FIG>, the third cable (connection member) 40B has three power supply connection lines (power supply port connection members) <NUM>, one ground connection line (ground port connection member) <NUM> and one communication connection line (communication port connection member) <NUM>. Each of the power supply connection lines <NUM>, the ground connection line <NUM> and the communication connection line <NUM> are the same things as the power supply connection line <NUM>, the ground connection line <NUM> and the communication connection line <NUM> of <FIG>, respectively. In the present embodiment, the three power supply connection lines <NUM> have the same electrical characteristics as one another. However, the present invention is not limited thereto. The power supply connection lines <NUM> may have electrical characteristics different from each other. Moreover, two of the power supply connection lines <NUM> may have electrical characteristics which are the same as each other and different from that of the remaining one of the power supply connection lines <NUM>.

As shown in <FIG>, each of the power supply connection lines <NUM> connects one of the power supply ports <NUM> of the feeding unit <NUM> and one of the power supply ports <NUM> of the connector unit <NUM> to each other. Here, the power supply ports <NUM> of the feeding unit <NUM> are connected to one another, and the power supply ports <NUM> of the connector unit <NUM> are connected to one another. Accordingly, the three power supply connection lines <NUM> form parallel lines which are connected to one another in parallel.

As understood from <FIG> and <FIG>, a voltage drop per unit length of the third cable 40B in the feeding system 10B of <FIG> is further smaller than the voltage drop per unit length of the second cable 40A in the feeding system 10A of <FIG>. Accordingly, even when a length of the third cable 40B is further longer than the length of the second cable 40A, an electric resistance or a voltage drop between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM> in the feeding system 10B of <FIG> can be adjusted to the same level as the electric resistance or the voltage drop of the feeding system 10A. Therefore, the feeding system 10B can supply a predetermined voltage to the connector unit <NUM> by using the third cable 40B.

As understood from the description mentioned above, the electric resistance or the voltage drop between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM> can be adjusted by selecting the number of the power supply connection lines <NUM> (the number of connections) between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM>. In particular, the electric resistance between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM> can be adjusted to the same level by selecting the number of connections between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM> according to a distance between the feeding unit <NUM> and the connector unit <NUM>. Thus, the feeding system <NUM>, 10A or 10B according to the present embodiment can supply the predetermined voltage to the connector unit <NUM> regardless of the distance between the feeding unit <NUM> and the connector unit <NUM>.

Additionally, there is a method which changes a diameter of the power supply connection line <NUM> as an adjusting method of the electric resistance or the voltage drop between the power supply port <NUM> of the feeding unit <NUM> and the power supply port <NUM> of the connector unit <NUM>. However, though increasing the diameter of the power supply connection line <NUM> reduces the electric resistance, disadvantage of wiring, such as reduction of flexibility, might be caused. Accordingly, it is more effective to select the number of connections than to change the diameter of the power supply connection line <NUM>.

In the aforementioned embodiment, the electric resistance or the voltage drop between the power supply ports <NUM> of the feeding unit <NUM> and the power supply ports <NUM> of the connector unit <NUM> is adjusted by selecting the number of the power supply connection lines <NUM>. However, the present invention is not limited thereto. For example, the number of the power supply connection line <NUM> may be set to one, and the number of the ground connection lines <NUM> may be selected. In that case, an electric resistance or a voltage drop between the ground ports <NUM> of the feeding unit <NUM> and the ground ports <NUM> of the connector unit <NUM> is adjusted. Alternatively, both of the number of the power supply connection lines <NUM> and the number of the ground connection lines <NUM> may be selected. In that case, the power supply connection lines <NUM> and the ground connection lines <NUM> must have the same electrical characteristics, and the number of the power supply connection lines <NUM> selected and the number of the ground connection line <NUM> selected must be the same as each other. In this way, the electric resistance between the feeding unit <NUM> and the connector unit <NUM> can be adjusted by selecting the number of connections between the specific ports <NUM> of the feeding unit <NUM> and the specific ports <NUM> of the connector unit <NUM>.

In the aforementioned embodiment, the ports <NUM> and <NUM> of the output portion <NUM> of the feeding unit <NUM> and the ports <NUM> and <NUM> of the input portion <NUM> of the connector unit <NUM> have the same structures as one another. However, the present invention is not limited thereto. The ports <NUM> and <NUM> may have different structure, such as different sizes, from each other. The ports may have different sizes from each other even if having the same function. For example, the power supply ports <NUM> and/or the ground ports <NUM> may be used for a thick connection line, a middle connection line and a thin connection line. In that case, as the power supply connection lines <NUM> or the ground connection lines <NUM>, the thick connection line, the middle connection line and the thin connection line can be selectively combined to be used. In this way, the number of choices regarding the electric resistance or the voltage drop can be increased in comparison with a case where the number of the power supply connection lines <NUM> same as each other or the ground connection lines <NUM> same as each other is selected.

Referring to <FIG>, a feeding system 10C according to a second embodiment of the present invention is provided with a feeding unit 20C and a connector unit 30C. Moreover, the feeding system 10C is provided with a fourth cable (connection member) 40C connecting the feeding unit 20C and the connector unit 30C to each other.

As shown in <FIG>, an output portion 26C of the feeding unit 20C is different from the output portion <NUM> of the feeding unit <NUM> of the first embodiment. In detail, the output portion 26C of the feeding unit 20C is provided with one power supply port <NUM>, one ground port <NUM> and one communication port <NUM>. Except for this point, the feeding unit 20C is formed in the same manner as the feeding unit <NUM> of the first embodiment. Moreover, an input portion 32C of the connector unit 30C is different from the input portion <NUM> of the connector unit <NUM> of the first embodiment. In detail, the input portion 32C of the connector unit 30C is provided with one power supply port <NUM>, one ground port <NUM> and one communication port <NUM>. Except for this point, the connector unit 30C is formed in the same manner as the connector unit <NUM> of the first embodiment.

As shown in <FIG>, the fourth cable 40C is provided with a power supply connection line (power supply port connection member) 42C, which connects the power supply port <NUM> of the feeding unit 20C and the power supply port <NUM> of the connector unit 30C to each other, and a ground connection line (ground port connection member) 44C, which connects the ground port <NUM> of the feeding unit 20C and the ground port <NUM> of the connector unit 30C to each other. In addition, the fourth cable 40C is provided with a communication connection line (communication port connection member) <NUM> which connects the communication port <NUM> of the feeding unit 20C and the communication port <NUM> of the connector unit 30C to each other.

As understood from <FIG>, the power supply connection line 42C of the fourth cable 40C has a pair of branching-joining portions, and two lines are connected between the branching-joining portions (in a middle section) in parallel. In this manner, in a partial section of the power supply connection line 42C, by providing a double parallel line section in which two lines are connected in parallel, an electric resistance or a voltage drop between the power supply port <NUM> of the feeding unit 20C and the power supply port <NUM> of the connector unit 30C can be smaller than that in a case of connecting by using a single line. The same is applied to the ground connection line 44C of the fourth cable 40C.

Referring to <FIG>, a feeding system 10D is provided with a fifth cable 40D different from the fourth cable 40C of the feeding system 10C of <FIG>. In detail, a power supply connection line 42D of the fifth cable 40D has a pair of branching-joining portions, and three lines are connected between the branching-joining portions (in a middle section) in parallel. In this manner, in a partial section of the power supply connection line 42D, by providing a triple parallel line section in which three lines are connected in parallel, an electric resistance or a voltage drop between the power supply port <NUM> of the feeding unit 20C and the power supply port <NUM> of the connector unit 30C can be smaller than that in a case of connecting with a single line or the cable having the double parallel line portion. The same is applied to the ground connection line 44D of the fifth cable 40D.

As understood from <FIG> and <FIG>, even when a length of the fifth cable 40D is longer than a length of the fourth cable 40C, the electric resistance or the voltage drop in the fifth cable 40D can be adjusted in the same level as the electric resistance or the voltage drop in the fourth cable 40C. This means that, by selecting the number of the lines which are connected in parallel in the middle section according to the distance between the feeding unit 20C and the connector unit 30C, the predetermined voltage can be supplied to the connector unit 30C regardless of the distance between the feeding unit 20C and the connector unit 30C. In other words, similarly to the first embodiment, also in the present embodiment, regardless of the distance between the feeding unit 20C and the connector unit 30C, the predetermined voltage can be supplied to the connector unit 30C.

In the aforementioned embodiment, the number of the parallel lines in the power supply connection line 42C or 42D is two or three. However, the present invention is not limited thereto. In the present invention, the number of line(s) (parallel lines) in the middle section in the power supply connection line should be at least one. The same is applied to the ground connection line.

Moreover, in the aforementioned embodiment, the number of the parallel lines of the power supply connection line 42C or 42D and the number of the parallel lines of the ground connection line 44C or 4D are equal to each other. However, the present invention is not limited thereto. In the present invention, the number of the parallel lines in the power supply connection line and the number of the parallel lines in the ground connection line may be different from each other.

As understood from the description mentioned above, in the present embodiment, at least one of the power supply port connection member and the ground port connection member is selected among a plurality of connection member options of plural kinds which are different from one another in the number of plural lines connecting the middle section according to the distance between the feeding unit 20C and the connector unit 30C. In this way, the predetermined voltage can be supplied to the connector unit 30C regardless of the distance between the feeding unit 20C and the connector unit 30C.

As mentioned above, the present invention can adjust the electric resistance or the voltage drop between the feeding unit <NUM> or 20C and the connector unit <NUM> or 30C by changing the number of the parallel lines at least in a partial section according to the length of connection thereof in at least one of a connection between the power supply ports <NUM> of the feeding unit <NUM> or 20C and the power supply ports <NUM> of the connector unit <NUM> or 30C and a connection between the ground ports <NUM> of the feeding unit <NUM> or 20C and the ground ports <NUM> of the connector unit <NUM> or 30C. In this way, the predetermined voltage can be supplied to the connector unit <NUM> or 30C regardless of the distance between the feeding unit <NUM> or 20C and the connector unit <NUM> or 30C.

Claim 1:
A connection method of connecting a feeding unit (<NUM>, 20C) provided with a power supply circuit with a connector unit (<NUM>, 30C) provided with a connector (<NUM>) to be connected to a user device, wherein
a connector unit (<NUM>, 30C) is suitable for a feeding system (<NUM>, 10A-D) in which a feeding unit (<NUM>, 20C) and the connector unit (<NUM>, 30C) are connected by a cable (<NUM>, 40A-D), wherein the connector unit (<NUM>, 30C) is provided with three or more specific ports (<NUM>) which comprise at least one power supply port (<NUM>) and at least one ground port (<NUM>) and which are configured to respectively correspond to three or more specific ports (<NUM>) included in the feeding unit (<NUM>, 20C) and comprising at least one power supply port (<NUM>) and at least one ground port (<NUM>) , wherein in each of the feeding unit (<NUM>, 20C) and the connector unit (<NUM>, 30C), plural ports having same function which are included in the specific ports (<NUM>, <NUM>) are connected to each other;
the connector (<NUM>) is a connector conformable to Universal Serial Bus (USB) standards; and
the method comprising, in at least one of a connection of the power supply port (<NUM>) of the feeding unit (<NUM>, 20C) and the power supply port (<NUM>) of the connector unit (<NUM>, 30C) and a connection of the ground port (<NUM>) of the feeding unit (<NUM>, 20C) and the ground port (<NUM>) of the connector unit (<NUM>, 30C), adjusting a voltage drop between the feeding unit (<NUM>, 20C) and the connector unit (<NUM>, 30C) by changing number of parallel lines in at least a partial section according to a length of the connection, wherein
the connector unit (<NUM>, 30C) further comprises a communication port (<NUM>);
the communication port (<NUM>) of the connector unit (<NUM>, 30C) is connected to the connector (<NUM>) in the connector unit (<NUM>, 30C); and
the communication port (<NUM>) of the connector unit (<NUM>, 30C) is for being connected to a communication port (<NUM>) provided in the feeding unit (<NUM>, 20C) to carry out communication conformable to the USB standards.