Patent Description:
A cart system of one type includes a processing terminal, such as a tablet terminal, and/or a barcode reader attached to a shopping cart. For example, such a cart system can support smoother shopping and settlement processing by a shopper himself or herself. A battery is mounted on the cart or the processing terminal. A method of charging the battery is required and thus methods for have been proposed for noncontact battery charging.

There is a power feeding device that includes a power transmission coil provided such that a power transmission surface is perpendicular to a floor surface and feeds electric power to a power reception coil provided on a side surface of a cart. There can also be a guiderail that guides the cart to a predetermined storage position in order for a power transmission coil and a power reception coil to perform suitable power reception and transmission. The guiderail is set to a size corresponding to the particular carts in use at the store location or the like.

However, a wheel width and an spacing between wheels may be different depending on a type of the cart. For that reason, once the guiderail is set, carts not compatible with the size of the guiderail may not be used.

<CIT> discloses a power receiving system, which includes a first receiving coil, a second receiving coil, a receiving circuit, a switching circuit, and a shorting circuit. The first receiving coil is at a first location on the cart. The second receiving coil is at a second location different from the first location on the cart. The receiving circuit generates direct current (DC) power from the power received by the first receiving coil or the second receiving coil. The switching circuit connects one of the first and second receiving coils to the receiving circuit. The shorting circuit disables the other one of the first and second receiving coils.

<CIT> discloses a cart storage system for storing a movable cart, which includes a storage plate inclined with respect to a floor in a first direction crossing a moving direction of a cart, a stopper along a back side of the storage plate in the moving direction, and a first holding plate extending along the moving direction, configured to stop movement of the cart in the lateral direction, and disposed a first predetermined distance away from a lateral side of the storage plate.

<CIT> discloses a power transmission system, which includes a power transmission antenna, a first rail and a second rail. The power transmission antenna is disposed facing the power reception antenna installed on the side surface of the cart stored in the storage position. The first rail includes a first groove that guides, among a plurality of wheels for moving the cart to the storage position, a first wheel that is closest to the power transmission antenna while the cart is stored in the storage position, and that causes a distance between the power reception antenna and the power transmission antenna installed on the side surface of the cart to be within a power transmittable range. The second rail includes a second groove that guides, among the plurality of wheels for moving the cart, a second wheel that is different from the first wheel to the storage position.

One of the objects of the present invention is to improve prior art techniques and overcome at least some of the prior art problems as for instance illustrated.

A cart charging system according to the present invention is defined by claim <NUM>. Dependent claims relate to preferred embodiments.

Optionally, in the cart charging system, the power transmission surface faces a side of the cart.

Optionally, the cart charging system further comprises a front wheel guide configured to restrict movement of at least one front wheel of the cart in the frontward direction.

Optionally, the front wheel guide is further configured to restrict movement of the at least one front wheel of the cart in one width direction of the cart.

Optionally, the cart charging system further comprises a rear wheel guide configured to restrict movement of a rear wheel in the frontward direction and the width directions.

Optionally, the cart charging system further comprises a wheel restricting member configured to restrict movement of the rear wheel in a rearward direction of the cart.

Optionally, the restricting member is made of a flexible material.

Optionally, the cart charging system further comprises an adjustable plate on which one rear wheel of the cart can be placed, the adjustable plate being adjustable such that another rear wheel of the cart can be higher than the other in a height direction.

Optionally, the second power feeding unit includes a second engaging member configured to engage with the power reception device of the second cart and restrict movement of the power reception device of the second cart in a frontward direction and width directions of the second cart.

Optionally, a distance between the first power feeding unit and the second power feeding unit is adjustable.

Optionally, the cart charging system further comprises a front wheel guide configured to restrict movement of at least one of front wheel of the first cart in the frontward direction.

Optionally, the front wheel guide is further configured to restrict movement of the at least one of front wheel of the first cart in one width direction of the first cart.

Optionally, the cart charging system further comprises a second engaging member configured to engage the power reception device of the second cart and restrict movement of the power reception device of the second cart in a frontward direction and width directions of the second cart.

Optionally, the cart charging system further comprises a front wheel guide configured to restrict movement of a front wheel of the first cart in the frontward direction.

Optionally, the front wheel guide is further configured to restrict movement of the front wheel in a width direction of the first cart.

An object is to provide a power feeding device in which power transmission and reception surfaces can be aligned.

In general, according to an embodiment, a cart charging system comprises a cart charging station which includes a supporting member, a power transmission device, and an engaging member, and comprises at least one cart. The power transmission device is on the supporting member so that a power transmission surface faces a power receiving surface of a power reception device on a cart stationed at the cart charging station. The power transmission device is configured to transmit electric power to the power reception device in a non-contact manner. The engaging member is configured to engage the power reception device of the stationed cart and restrict movement of the power reception device of the cart in a frontward direction of the cart and width directions of the cart.

Examples of a shopping cart <NUM> mounted with a power feeding device <NUM> and a power reception device <NUM> that receives electric power transmitted from the power feeding device <NUM> according to embodiments are described below with reference to the drawings. The power feeding device <NUM> may be referred to as a cart charging station. The power feeding device <NUM> and the power reception device <NUM> need to be in a predetermined positional relation for a power transmission and reception system that can perform noncontact power feeding. In the following explanation, a direction along an advancing direction of the shopping cart <NUM> may be referred to as a width direction of the cart.

<FIG> illustrates a perspective view of the shopping cart <NUM> with the power reception device <NUM> that can be used to receive electric power transmitted from the power feeding device <NUM> according to an embodiment. <FIG> illustrates a perspective view of a configuration of the power feeding device <NUM> and an example of a relation between the power feeding device <NUM> and the shopping cart <NUM>.

<FIG> and <FIG> illustrate perspective views of a configuration of a power transmission device <NUM> of the power feeding device <NUM> and an example of a relation between the power transmission device <NUM> and the power reception device <NUM> of the shopping cart <NUM>. <FIG> and <FIG> illustrate the perspective views from different directions.

<FIG> and <FIG> are block diagrams illustrating an example of a configuration of a power transmission and reception system in which the power feeding device <NUM> and the power reception device <NUM> according to the embodiment can be used.

First, the shopping cart <NUM> with the power reception device <NUM> is described with reference to <FIG>.

The shopping cart <NUM> is an example of a mobile body on which the power reception device <NUM> is mounted. The power reception device <NUM> is configured to receive electric power transmitted from the power feeding device <NUM>. In the following description, the shopping cart <NUM> is simply referred to as cart <NUM>.

The cart <NUM> has the power reception device <NUM> mounted thereon. The power reception device <NUM> can receive electric power transmitted in a noncontact manner. "Noncontact" in this context means without a wired connection, plug connectors, or the like. Noncontact may refer to wireless (RF) transmissions, inductive coupling, or the like. The power reception device <NUM> supplies the received electric power to a battery of an electronic device mounted on the cart <NUM>. The power feeding device <NUM> transmits electric power that is receivable by a power reception system mounted on the cart <NUM>. For example, the power feeding device <NUM> forms part of a cart storage space where the cart <NUM> can be stored. The power feeding device <NUM> transmits electric power in a noncontact manner to the power reception device <NUM> mounted on the stored cart <NUM>.

The battery charged by the power reception device <NUM> is, for example, a power supply device that supplies electric power to an electronic device mounted on the cart <NUM>. The battery charged by the power reception device <NUM> may be included in the electronic device mounted on the cart <NUM>. The battery charged by the power reception device <NUM> may be mounted on the cart <NUM> separately from the electronic device. In this present embodiment, the electronic device includes the battery.

In <FIG> and <FIG>, the cart <NUM> includes a cart main body <NUM> that is movable and stores commodities, an electronic device <NUM>, a battery <NUM>, and the power reception device <NUM>. The electronic device <NUM> and the power reception device <NUM> can be attached to the cart main body <NUM>. A plurality of carts <NUM> can be stacked front-to-rear for storage or the like.

The cart main body <NUM> moves when pushed by a user. The cart main body <NUM> stores commodities therein or alternatively holds a shopping basket for storing commodities. As illustrated in <FIG>, the cart main body <NUM> includes a frame <NUM>, a plurality of casters <NUM>, and a storage basket <NUM>.

The frame <NUM> includes, for example, a vertical frame <NUM>, a horizontal frame <NUM>, and a handle <NUM>. Two casters <NUM> (rear wheels) are provided at the lower end of the vertical frame <NUM>. The handle <NUM> is provided at the upper end of the vertical frame <NUM>. The vertical frame <NUM> extends in the up-down direction. The vertical frame <NUM> may partially incline or bend or may linearly extend. An extending direction of the vertical frame <NUM> may be along the up-down direction or may be inclined with respect to the up-down direction and can be set as appropriate.

The vertical frame <NUM> includes a pair of main frames <NUM> disposed in the width direction of the cart <NUM> and extended in the up-down direction. A part of the pair of main frames <NUM> is bent. The vertical frame <NUM> may include a subframe in addition to the pair of main frames <NUM>.

The horizontal frame <NUM> is integrally connected to the lower end side of the vertical frame <NUM>. The horizontal frame <NUM> extends in the front-rear direction. The horizontal frame <NUM> may partially incline or bend or may linearly extend. An extending direction of the horizontal frame <NUM> may be along the front-rear direction or may be inclined with respect to the front-rear direction and can be set as appropriate. Two casters <NUM> c (front wheels) are provided on the lower surface on the distal end side of the horizontal frame <NUM>. The horizontal frame <NUM> includes, for example, a base frame <NUM> on which the casters <NUM> are provided and a subframe <NUM> provided further on the inner side or the lower side than the base frame <NUM>.

The base frame <NUM> decreases in width from the rear toward the front in this example. The base frame <NUM> is set to have a width for enabling a shopping basket to be placed inside. The base frame <NUM> is formed to become narrower from the rear to the front side. The base frame <NUM> has, for example, a width the same as the width of the pair of main frames <NUM>. Two casters <NUM> forming the front wheels are provided at the lower ends of two parts on the lower surface in the front of the base frame <NUM>.

The subframe <NUM> extends in the front-rear direction. The subframe <NUM> is disposed on the inner side of the base frame <NUM>. When a shopping basket is placed in the base frame <NUM>, the subframe <NUM> supports the shopping basket. When the carts <NUM> are stacked, the distal end of the subframe <NUM> comes into contact with the subframe <NUM> of the other cart <NUM> to hold the adjacent stacked carts <NUM> in a predetermined positional relation.

The handle <NUM> is provided at the upper end of the vertical frame <NUM>. The handle <NUM> is provided, for example, at the upper ends of the pair of main frames <NUM> to be laid across the pair of main frames <NUM>. The handle <NUM> is gripped by the user and pressed in the traveling direction by the user to move and turn the cart main body <NUM>. The handle <NUM> may be provided at each of the upper ends of the pair of main frames <NUM>.

For example, four casters <NUM> are provided. The four casters <NUM> are disposed at the lower ends of the frame <NUM>. As a specific example, among the four casters <NUM>, two casters <NUM> are provided as rear wheels <NUM> at the lower ends of the pair of main frames <NUM> of the vertical frame <NUM>.

Two casters <NUM> are provided as front wheels <NUM> on the lower surface on the front end side of the base frame <NUM> of the horizontal frame <NUM>. An interval between two rear wheels <NUM> is wider than the interval between two front wheels <NUM>.

For example, the casters <NUM> are joined to the frame <NUM>. As a specific example, the rear wheels <NUM> are fixed to the lower ends of the pair of main frames <NUM> of the vertical frame <NUM>. The front wheels <NUM> are fixed to two parts on the front lower surface of the base frame <NUM> of the horizontal frame <NUM>.

The storage basket <NUM> stores commodities or holds a shopping basket storing commodities. The storage basket <NUM> can be formed in a box shape opening upward by a perforated panel member or a mesh wire member. For example, the storage basket <NUM> is integrally joined to the vertical frame <NUM>. For example, the storage basket <NUM> is fixed to the pair of main frames <NUM> of the vertical frame <NUM> and supported. The storage basket <NUM> is formed to become narrower from the rear to the front side in the advancing direction. The storage basket <NUM> includes, on the rear end side, an opening and closing section <NUM> that is capable of swinging with the lower end free and the upper end set as a rotation point. The size in the width direction and the size in the height direction of the storage basket <NUM> are set to be larger on the rear end side, which is the opening and closing section <NUM>, than on the front end side.

If a plurality of such cart main bodies <NUM> are placed in a row and pushed together for storage, the cart main body <NUM> in the rear pushes up the opening and closing section <NUM> of the cart main body <NUM> in the front. The storage baskets <NUM> of the cart main bodies <NUM> in the front and the rear thus overlap. The horizontal frame <NUM> of the cart main body <NUM> in the rear is inserted from between the pair of main frames <NUM> of the cart main body <NUM> in the front and is stored in the base frame <NUM> of the horizontal frame <NUM> of the cart main body <NUM> in the front. The subframe <NUM> of the cart main body <NUM> in the rear comes into contact with the subframe <NUM> of the cart main body <NUM> in the front. A positional relation between the adjacent cart main bodies <NUM> in the front and the rear becomes a fixed positional relation. Consequently, the carts <NUM> can be stacked front to the rear and stored.

The electronic device <NUM> is a device for provision of information to the user and/or provision of a service(s) to the user. One or more electronic devices <NUM> can be provided. An example of an electronic device <NUM> is illustrated in <FIG>, <FIG>, and <FIG>. However, the electronic device <NUM> is omitted in other figures for sake of clarity.

The electronic device <NUM> is attached to the cart main body <NUM>. In <FIG>, the electronic device <NUM> is held by, the handle <NUM> of the cart main body <NUM>. As illustrated in <FIG>, the electronic device <NUM> includes the battery <NUM>. An electronic device <NUM> may have a function or a configuration for displaying commodity information, store information, and the like. For example, an electronic device <NUM> may have a function or a configuration for performing processing such as image processing, commodity reading processing, product registration processing, and transaction settlement processing based on commodity information such as a commodity code.

As a specific example, the electronic device <NUM> is an information terminal, such as a tablet terminal, for providing information to the user, a commodity reader for acquiring information concerning a commodity selected by the user, or a card reader for reading a credit card, a member card, and the like. The electronic device <NUM> may also be a charging device for charging, with electronic power received from the battery <NUM>, an electronic device or a portable terminal carried by the user. Examples of a portable terminal that might be carried by the user include a cellular phone, a smartphone, a digital camera, and a tablet terminal. However, the portable terminal is not limited to these devices.

In the example illustrated in <FIG> and <FIG>, the cart <NUM> includes a tablet terminal <NUM> and a commodity reader <NUM> as electronic devices <NUM>. The tablet terminal <NUM> is, for example, a processing terminal including a control circuit <NUM> including a processor and a memory, a display unit <NUM> such as a display including a touch panel, and an I/F unit <NUM> connected to another electronic device <NUM>. In the present embodiment, the tablet terminal <NUM> incorporates the battery <NUM> therein. The tablet terminal <NUM> has the display unit <NUM> directed towards a user on the handle <NUM> side. As a specific example, the tablet terminal <NUM> is provided in the handle <NUM> via an arm shaft <NUM> (the height and the posture of which can be changed) attached to the handle <NUM>.

The tablet terminal <NUM> may be fixed directly to the frame <NUM>. That is, various attaching structures and methods for tablet terminal <NUM> can be selected. The electronic device <NUM> may be attached to the frame <NUM> such that the posture and the height thereof can be changed, may be attached such that only the posture or only the height thereof can be changed, or may be fixed to the frame <NUM> such that the posture and the height thereof cannot be changed.

The tablet terminal <NUM> displays, on the display unit <NUM>, information concerning a commodity read by the commodity reader <NUM>. The tablet terminal <NUM> may perform settlement processing for the commodity read by the commodity reader <NUM>.

The commodity reader <NUM> reads information from a commodity. The commodity reader <NUM> can be a scanner that reads commodity identification information such as a barcode on a commodity put in and taken out from the storage basket <NUM>. As a specific example, the commodity reader <NUM> is provided in the handle <NUM> via a holder <NUM> or the like attached to the handle <NUM> and having a posture fixed with a reading unit, which reads information concerning a commodity, directed to the front or toward the storage basket <NUM>.

The commodity reader <NUM> may incorporate the battery <NUM> and include a control circuit including a processor and a memory, a reading unit that reads commodity identification information, a display unit that displays information, and an I/F unit connected to another electronic device <NUM> such as the tablet terminal <NUM>.

The commodity reader <NUM> may also or instead be an RFID tag reader for reading an RFID tag or the like attached to a commodity. The commodity reader <NUM> may be part of the tablet terminal <NUM> or a portable terminal carried by the user. If the tablet terminal <NUM> or the portable terminal is the commodity reader <NUM>, processing for reading commodity identification information such as a barcode can be performed. In some examples, processing associated with imaging a commodity to obtain the commodity identification information from a captured image can be performed. A camera may be provided in the tablet terminal <NUM> or in a portable terminal carried by the user. A card reader <NUM> reads a credit card, a member card, or the like for the user.

The electronic device <NUM> may be, instead of the tablet terminal <NUM>, an interface device for connecting the user's own portable terminal. A user's portable terminal connected to the interface device functioning as the electronic device <NUM> may perform the same processing as the processing of the tablet terminal <NUM> described above. The interface device functioning as the electronic device <NUM> may charge a battery included in the user's portable terminal. The interface device functioning as the electronic device <NUM> may incorporate the battery <NUM> or may be connected to the battery <NUM> provided separately from the interface device.

The battery <NUM> is a power supply device for enabling the electronic device <NUM> to operate. The battery <NUM> is incorporated in, for example, the electronic device <NUM>. For example, as illustrated in <FIG>, the battery <NUM> is incorporated in, for example, the tablet terminal <NUM>. The battery <NUM> may be a battery incorporated in the commodity reader <NUM>, the tablet terminal <NUM>, or separately provided. The battery <NUM> includes a secondary battery <NUM> that stores electric power and a charging circuit <NUM> that charges the secondary battery <NUM> with electric power received from the power reception device <NUM>. The battery <NUM> may be a power supply device provided on the outside of the electronic device <NUM>. The secondary battery <NUM> and the charging circuit <NUM> may be housed in a battery case of the battery <NUM>. The battery <NUM> only has to be configured to supply the electric power stored in the secondary battery <NUM> to the electronic device <NUM>.

The secondary battery <NUM> is charged by charging power supplied from the charging circuit <NUM>.

The charging circuit <NUM> supplies the electric power supplied from the power reception device <NUM> to the secondary battery <NUM> as electric power for charging (charging power). For example, the charging circuit <NUM> converts electric power supplied from a power reception circuit <NUM> described below of the power reception device <NUM> into a direct current (charging power) used for charging the secondary battery <NUM>. That is, the charging circuit <NUM> converts the electric power supplied from the power reception circuit <NUM> into charging power having a predetermined current value and a predetermined voltage value for charging the secondary battery <NUM> and supplies the charging power to the secondary battery <NUM>.

The power reception device <NUM> receives electric power transmitted from a power transmission device functioning as an external device. The power reception device <NUM> charges the battery <NUM> with the received electric power. The power reception device <NUM> supplies the received electric power to the electronic device <NUM> or the battery <NUM>.

The power reception device <NUM> is attached to the frame <NUM> of the cart main body <NUM>. For example, as illustrated in <FIG>, the power reception device <NUM> is provided to range over the vertical frame <NUM> and the horizontal frame <NUM>. As a specific example, the power reception device <NUM> is attached to a side at the rear end of the frame <NUM>. The power reception device <NUM> is provided to span between the vertical frame <NUM> and the horizontal frame <NUM> such that the power reception surface at which a power reception coil <NUM> receives electric power (from a power transmission coil on a power transmission side) will be parallel to or substantially parallel to a power transmission surface.

The power reception device <NUM> receives electric power output from the power transmission device <NUM> in the power feeding device <NUM>. The power reception device <NUM> is disposed such that the power reception coil <NUM>, which is the power reception surface of the power reception device <NUM>, faces a power transmission coil <NUM>, which is the power transmission surface of the power transmission device <NUM> in the power feeding device <NUM>.

As illustrated in <FIG>, the power reception device <NUM> includes the power reception coil <NUM>, the power reception circuit <NUM>, a control circuit <NUM>, a display unit <NUM>, and a capacitor for resonance <NUM>. The power reception device <NUM> is configured by, for example, housing the power reception coil <NUM>, the power reception circuit <NUM>, the control circuit <NUM>, the display unit <NUM>, and the capacitor for resonance <NUM> in a case <NUM>.

The power reception coil <NUM> receives electric power from the power transmission device <NUM> and supplies the electric power to the power reception circuit <NUM>. In the power reception coil <NUM>, the power reception surface for receiving electric power is formed in a flat shape. The power reception surface of the power reception coil <NUM> is provided on the frame <NUM> of the cart main body <NUM>, for example, with the power reception surface of the power reception coil <NUM> being disposed to be parallel to the power transmission surface of the power transmission coil <NUM>. The power reception coil <NUM> can be connected in series or in parallel to the capacitor for resonance <NUM> for power reception to thereby configure a resonance circuit (a power reception resonance circuit).

When approaching the power transmission coil <NUM> of the power transmission device <NUM>, the power reception coil <NUM> (functioning as the power reception resonance circuit) electromagnetically couples to the power transmission coil <NUM>. In the power reception coil <NUM>, an induction current is generated by a magnetic field output from the power transmission coil <NUM> of the power transmission device <NUM>. The power reception coil <NUM> may be configured as a wound structure obtained by winding an insulated electric wire or may be configured by forming a coil pattern on a printed board.

The power reception coil <NUM> supplies received AC power to the power reception circuit <NUM>. In other words, the power reception coil <NUM> functions as an AC power supply while receiving the AC power from the power transmission device <NUM>. For example, if a magnetic field resonance scheme is used for power transmission, a self-resonance frequency of the power reception resonance circuit functioning as the power reception coil <NUM> is set to substantially the same frequency as a frequency of power transmission by the power transmission device <NUM>. As a result, power transmission efficiency in the electromagnetic coupling of the power reception coil <NUM> and the power transmission coil <NUM> is improved.

The power reception circuit <NUM> converts received power supplied from the power reception coil <NUM> into electric power suppliable to the battery <NUM>. For example, the power reception circuit <NUM> rectifies the received power supplied from the power reception coil <NUM> and converts the received power into a direct current. Such a power reception circuit <NUM> is achieved by, for example, a circuit including a rectifying bridge configured by a plurality of diodes. In this case, a pair of input terminals of the rectifying bridge is connected to the power reception resonance circuit configured from the power reception coil <NUM> and the capacitor for resonance <NUM>. The power reception circuit <NUM> full-wave rectifies the received power supplied from the power reception coil <NUM> to thereby output DC power from a pair of output terminals.

The control circuit <NUM> controls the operations of the power reception circuit <NUM> and the display unit <NUM>. The control circuit <NUM> includes a processor and a memory. The processor executes arithmetic processing. The processor performs various kinds of processing based on, for example, a program stored in the memory and data used in the program. The memory stores the program, the data used in the program, and the like. The control circuit <NUM> may be configured by a microcomputer and/or an oscillation circuit or the like. For example, the control circuit <NUM> switches a display state (e.g., color) or display contents of the display unit <NUM> according to a state of the power reception device <NUM>.

The display unit <NUM> is a display device that displays various kinds of information. For example, the display unit <NUM> is an indicator indicating a state of the power reception device <NUM>. The display unit <NUM> switches display according to control by the control circuit <NUM>. For example, the display unit <NUM> is an LED and switches lighting, extinction, or a display color according to an operation state of the power reception device <NUM>. The display unit <NUM> may display the operation state as a message on a liquid crystal screen.

In the power reception device <NUM>, a wireless communication circuit for performing wireless communication with the power transmission device <NUM> corresponding to the power reception device <NUM> may be provided. For example, the wireless communication circuit is a circuit that performs wireless communication at a frequency different from a frequency of power transmission. If the wireless communication circuit is provided in the power reception device <NUM>, the control circuit <NUM> may perform wireless communication with the power transmission device <NUM> through the wireless communication circuit to thereby perform control of the units. The wireless communication circuit may perform wireless communication at the same frequency as the frequency of the power transmission using load modulation.

The power feeding device <NUM> is described with reference to <FIG>.

As illustrated in <FIG>, the power feeding device <NUM> includes a cart guide <NUM>, a plurality of power transmission devices <NUM>, and one or more supporting members <NUM>. In the present embodiment, the supporting members <NUM> and the power transmission devices <NUM> are provided in the same number.

The cart guide <NUM> is provided in a cart storage space where the carts <NUM> are stacked and stored. The cart guide <NUM> guides the position of the first cart <NUM> among the stacked carts <NUM>. The car guide <NUM> may be referred to as a front wheel guide. For example, the width of the cart guide <NUM> is set larger on the rear side than the front side in the traveling direction of the cart <NUM>. An end portion of the cart guide <NUM> comes into contact with the front wheels <NUM> of the cart main body <NUM> and can control the position of the first cart <NUM> in the traveling direction. If the cart guide <NUM> can at least control the position of the first cart <NUM> among the stacked carts <NUM>, the shape and the configuration of the cart guide <NUM> can be varied as appropriate.

As illustrated in <FIG>, the power transmission device <NUM> includes a power supply circuit <NUM>, a power transmission circuit <NUM>, a power transmission coil <NUM>, a control circuit <NUM>, a display unit <NUM>, and a capacitor for resonance <NUM>. The power transmission device <NUM> includes an AC adapter <NUM> connected to the power supply circuit <NUM> and connected to, for example, a power supply of a store. For example, the power supply circuit <NUM>, the power transmission circuit <NUM>, the power transmission coil <NUM>, the control circuit <NUM>, the display unit <NUM>, and the capacitor for resonance <NUM> are integrally provided in a casing or the like and respectively disposed in the supporting members <NUM>. For example, if a plurality of components of the power transmission device <NUM> are separately configured, at least a component including the power transmission coil <NUM> is disposed in the supporting member <NUM>.

The power supply circuit <NUM> converts a voltage of a DC power supply from the outside into a voltage suitable for the operations of the circuits. The power supply circuit <NUM> generates electric power for enabling the power transmission circuit <NUM> to perform power transmission and supplies the electric power to the power transmission circuit <NUM>. The power supply circuit <NUM> generates electric power for enabling the control circuit <NUM> to operate and supplies the electric power to the control circuit <NUM>.

The power transmission circuit <NUM> generates transmission power to be transmitted from the power transmission coil <NUM>. The power transmission circuit <NUM> supplies the generated transmission power to the power transmission coil <NUM>. For example, the power transmission circuit <NUM> switches, based on control by the control circuit <NUM>, DC power supplied from the power supply circuit <NUM> to AC power serving as transmission power.

The power transmission coil <NUM> outputs, according to the transmission power supplied from the power transmission circuit <NUM>, electric power receivable by the power reception device <NUM>. In the power transmission coil <NUM>, a power transmission surface for transmitting electric power is formed in a plane shape. The power transmission surface of the power transmission coil <NUM> is disposed in the supporting member <NUM> in a posture orthogonal to the floor surface and to face the power reception surface of the power reception coil <NUM> of the power reception device <NUM>.

For example, the power transmission coil <NUM> is connected in series or parallel to the capacitor for resonance <NUM> to thereby configure a resonance circuit (a power transmission resonance circuit). If AC power is supplied from the power transmission circuit <NUM>, the power transmission coil <NUM> functioning as the power transmission resonance circuit generates a magnetic field corresponding to the supplied AC power. The power transmission coil <NUM> may be configured as a wound structure obtained by winding an insulated electric wire or may be configured by forming a coil pattern on a printed board.

The control circuit <NUM> controls the operations of the power transmission circuit <NUM> and the display unit <NUM>. The control circuit <NUM> includes a processor and a memory. The processor executes arithmetic processing. The processor performs various kinds of processing based on, for example, a program stored in the memory and data used in the program. The memory stores the program, the data used in the program, and the like. The control circuit <NUM> may be configured by a microcomputer and/or an oscillation circuit or the like.

For example, the control circuit <NUM> switches a display state (e.g., color) or display contents of the display unit <NUM> according to a state of the power transmission device <NUM>. The control circuit <NUM> controls a frequency of AC power output from the power transmission circuit <NUM> and controls ON and OFF of the operation of the power transmission circuit <NUM>. For example, the control circuit <NUM> controls the power transmission circuit <NUM> to thereby switch to a state (a power transmission state) causing the power transmission coil <NUM> to generate a magnetic field or a standby state not causing the power transmission coil <NUM> to generate a magnetic field. The control circuit <NUM> may perform control for causing the power transmission coil <NUM> to intermittently generate a magnetic field and changing timing for transmitting electric power.

The display unit <NUM> can be an indicator indicating a state of the power transmission device <NUM>. The display unit <NUM> switches display according to the control by the control circuit <NUM>. For example, the display unit <NUM> is an LED and switches lighting, extinction, or a display color according to an operation state of the power transmission device <NUM>. The display unit <NUM> may display the operation state as a message on a liquid crystal screen.

The supporting member <NUM> is provided on the floor surface on which the power supply device <NUM> is set. The supporting member <NUM> supports the power transmission device <NUM> in a posture in which the power transmission surface of the power transmission coil <NUM> is parallel to the power reception coil <NUM> of the power reception device <NUM> of the cart <NUM>. The supporting member <NUM> holds the cart <NUM> in a predetermined position. The plurality of supporting members <NUM> respectively support the power transmission devices <NUM> and are disposed at equal intervals along the traveling direction of the cart main body <NUM>.

A disposition interval for the plurality of supporting members <NUM> is an interval at which, when the carts <NUM> are stacked, the power reception devices <NUM> of the carts <NUM> and the power transmission devices <NUM> supported by the supporting members <NUM> are opposite to one another (in a facing arrangement).

As a specific example, the supporting member <NUM> includes a base <NUM>, a wall section <NUM>, and engaging sections <NUM>. The base <NUM> is formed in, for example, a rectangular plate shape. The rear wheel <NUM> on a side where the power reception device <NUM> is provided of the cart main body <NUM> can be disposed on the upper surface of the base <NUM>. The base <NUM> supports the wall section <NUM>. The base <NUM> includes, on the upper surface, a rear wheel guide <NUM> that controls the position of the rear wheel <NUM> of the cart main body <NUM>.

The rear wheel guide <NUM> guides, for example, a position in the front in the traveling direction and a position in the width direction of the rear wheel <NUM>. As a specific example, if the rear wheel <NUM> is disposed on the base <NUM>, the rear wheel guide <NUM> guides the position of the rear wheel <NUM> such that the power transmission device <NUM> supported by the supporting member <NUM> and the power reception device <NUM> of the cart main body <NUM> are in a predetermined positional relation. The rear wheel guide <NUM> is, for example, an L-shaped protrusion, the rear side of the base <NUM> of which is open and an end portion of which continues to the wall section <NUM>. In other words, the rear wheel guide <NUM> is a protrusion extending along the traveling direction of the cart main body <NUM> and the width direction orthogonal to the traveling direction.

The wall section <NUM> is formed in, for example, a plate shape. The wall section <NUM> is provided on the base <NUM>, for example, in a posture in which a principal plane of the wall section <NUM> extends along the traveling direction of the cart main body <NUM>. The wall section <NUM> supports the power transmission device <NUM> on a principal plane opposed to the cart main body <NUM>. The wall section <NUM> may include the power transmission device <NUM> therein rather than support the power transmission device <NUM> thereout.

The engaging sections <NUM> are guides that engage with the power reception device <NUM> to perform alignment of the power reception device <NUM> and the power transmission device <NUM>. Each of the engaging sections <NUM> may be referred to as an engaging member. The engaging sections <NUM> come into contact with, in the traveling direction of the cart main body <NUM>, the front end of the case <NUM> of the power reception device <NUM> and a surface on the opposite side of a surface of the case <NUM> opposed to the power transmission device <NUM> or are slightly separated from and opposed to the front end or the surface to define the position of the power reception device <NUM>. For example, the engaging sections <NUM> are provided in two parts on the upper end side and the center side of the wall section <NUM>.

As a specific example, as illustrated in <FIG> and <FIG>, the engaging sections <NUM> are configured by first plate sections <NUM> provided along the width direction of the cart main body <NUM> from the front end portion of the wall section <NUM> and second plate sections <NUM> extending rearward in a direction along the traveling direction of the cart main body <NUM> from the end portions in the width direction of the first plate sections <NUM>. The first plate sections <NUM> and the second plate sections <NUM> are in contact with or opposed to the case <NUM> of the power reception device <NUM>, whereby the engaging sections <NUM> guide the positions in the traveling direction and the width direction of the power reception device <NUM>.

The engaging sections <NUM> are set to a shape for bringing the power transmission coil <NUM> of the power transmission device <NUM> and the power reception coil <NUM> of the power reception device <NUM> into a predetermined distance relation for enabling efficient power feeding if the position of the power reception device <NUM> is guided. The case <NUM> of the power reception device <NUM> may be fit in the engaging sections <NUM> to define the position of the power reception device <NUM> and restrict movement of the cart main body <NUM>.

In such a power feeding device <NUM>, the cart guide <NUM> and the plurality of supporting members <NUM>, in which the plurality of power transmission devices <NUM> are provided, are set on the floor surface of the cart storage space. If the cart guide <NUM> and the supporting members <NUM> are not moved by the cart <NUM>, the cart guide <NUM> and the supporting members <NUM> are set on the floor surface as appropriate. For example, the cart guide <NUM> and the supporting members <NUM> may be fixed to the floor surface by bolts or the like, may be fixed to the floor surface by an adhesive, or may be fixed to the floor surface by another method. If the cart guide <NUM> and the supporting members <NUM> do not move when the cart <NUM> is stored, the cart guide <NUM> and the supporting members <NUM> may not be fixed to the floor surface.

If the cart <NUM> is stored to be capable of feeding power to the power feeding device <NUM>, first, the head cart <NUM> is advanced until the front wheels <NUM> come into contact with the cart guide <NUM>. At the same time, as indicated by arrows in <FIG>, the rear wheel <NUM> is moved to the inside of the rear wheel guide <NUM> of the base <NUM> on which the rear wheel <NUM> is disposed. The next cart <NUM> is stacked in the already stored cart <NUM> and, as indicated by the arrows in <FIG>, the rear wheel <NUM> is moved to the rear wheel guide <NUM> of the base <NUM> on which the rear wheel <NUM> is disposed. Consequently, the carts <NUM> are stored in the cart storage space.

With the power feeding device <NUM> configured in this way, a pair of front wheels <NUM> of the head cart <NUM> is guided by the cart guide <NUM>. The distal end portions of the carts <NUM> other than the head cart <NUM> are stacked in the carts <NUM> located in the front and are stored. Consequently, the position in the traveling direction of the cart <NUM> is guided by the cart guide <NUM> or the cart <NUM> in the front, the engaging sections <NUM>, and the rear wheel guide <NUM>. The position in the width direction of the cart <NUM> is guided by the engaging sections <NUM> and the rear wheel guide <NUM>.

Forward movement the cart <NUM> stored in the cart storage space is restricted by the cart guide <NUM> or another cart <NUM> in the front of the cart <NUM>, the engaging sections <NUM>, and the rear wheel guide <NUM> and movement in the width directions of the cart <NUM> is restricted by the engaging sections <NUM> and the rear wheel guide <NUM>. At this time, the power reception coil <NUM> of the power reception device <NUM> is opposed to the power transmission coil <NUM> of the power transmission device <NUM> at a preset distance for enabling efficient power transmission in noncontact power feeding. That is, the power feeding device <NUM> can set the position of the power reception coil <NUM> in a positional relation suitable for power feeding with respect to the power transmission coil <NUM> and maintain such a positional relation.

Therefore, the power reception device <NUM> and the power feeding device <NUM> are capable of performing efficient power transmission. In the power feeding device <NUM>, the power transmission and reception surfaces of the power reception device <NUM> and the power transmission device <NUM> can be aligned by the cart guide <NUM>, the rear wheel guide <NUM>, and the engaging sections <NUM>. Accordingly, the power feeding device <NUM> can be configured not to include the guiderail for defining the position of the cart <NUM>. Accordingly, the power feeding device <NUM> can be reduced in size.

In the power feeding device <NUM>, the power transmission device <NUM> is provided in the wall section <NUM> of the supporting member <NUM> and the base <NUM> is set on the floor surface. Therefore, even if a type of the cart <NUM> used in the store is changed, the power feeding device <NUM> is capable of performing suitable power feeding if the disposition position of the power transmission device <NUM> is changed.

That is, when a cart type used in a store is changed, the size, dimensions, shapes, and the like of the cart and its rear wheels, frame, and power reception device may be different from the cart type in use previously at the store. If so, the power feeding device <NUM> that was set to enable efficient power transmission to the previous cart type before the change might not be useable with the new cart type.

However, with the power feeding device <NUM> in the present embodiment, the base <NUM> for supporting the power transmission device <NUM> only has to be set, via the wall section <NUM>, in a position where the power reception coil <NUM> and the power transmission coil <NUM> of the stored cart <NUM> are at an appropriate distance for enabling efficient power transmission by noncontact power feeding. Therefore, if the type of the cart <NUM> used in the store is changed, by changing a position of the base <NUM> according to a shape of the new cart <NUM>, it is possible to adjust the position of the power transmission coil <NUM> for the power reception coil <NUM> of the new cart <NUM>. Accordingly, with the power feeding device <NUM>, it is unnecessary to significantly change a layout or setup a new power feeding device for a new cart <NUM> of a different type. In the power feeding device <NUM>, since the guiderail is unnecessary, if the type of the cart <NUM> in use is changed, it is unnecessary to, for example, change setting of the guiderail.

In the power feeding device <NUM>, the power transmission and reception surfaces of the power reception device <NUM> and the power transmission device <NUM> can be aligned by changing the disposition of the base <NUM>. Therefore, the power feeding device <NUM> can be applied to various carts <NUM>. Further, in the power feeding device <NUM>, the number of the power transmission devices <NUM> can be changed according to the number of stacked carts <NUM>. Accordingly, the power feeding device <NUM> has a high degree of freedom in application thereof.

With the power feeding device <NUM>, it is possible to align the power transmission and reception surfaces.

The configurations of the power feeding device <NUM>, the cart <NUM>, and the like are not limited to the specific configurations described above. For example, the power transmission device <NUM> may include a wireless communication circuit for performing wireless communication. For example, the wireless communication circuit is a circuit that performs wireless communication at a frequency different from a frequency of power transmission. The control circuit <NUM> of the power transmission device <NUM> may perform control of the units by performing wireless communication with the power reception device <NUM> through the wireless communication circuit. The wireless communication circuit may perform the wireless communication at the same frequency as the frequency of the power transmission using load modulation.

In the example described above, the power feeding device <NUM> is configured with the base <NUM> and the engaging sections <NUM> so as to restrict the movement to the front in the traveling direction and the movement in the width directions of the cart <NUM>. However, the power feeding device <NUM> is not limited to this. For example, like a power feeding device <NUM> according to another embodiment illustrated in <FIG>, a power feeding device <NUM> may be configured to restrict movement to the rear in a traveling direction of the cart <NUM>. The restriction of the rearward movement of the cart <NUM> in this context means that the cart <NUM> is prevented from easily moving from the state in which the power transmission and reception surfaces are aligned due to a cause such as a shock associated with the stacking of additional carts <NUM> or the like, but does not include preventing the rearward movement of the cart <NUM> by a user such as when a user wishes to withdraw a cart <NUM> from a stack of carts <NUM>. For example, a component that restricts the rearward movement of the cart <NUM> is a protrusion <NUM> provided behind the rear wheel guide <NUM> of the base <NUM>. The protrusion <NUM> is preferably set to height lower than the rear wheel guide <NUM> as height for allowing the rear wheel <NUM> to easily run on the protrusion <NUM>. The protrusion <NUM> may be referred to as a wheel restricting member.

A component that restricts the rearward movement of the cart <NUM> according to the invention is a restricting member <NUM> with which the vertical frame <NUM> provided in the wall section <NUM> or the case <NUM> of the power reception device <NUM> comes into contact. If the rear wheel <NUM> and a case <NUM> of the power reception device <NUM> are disposed in the rear wheel guide <NUM> and the engaging sections <NUM>, the restricting member <NUM> comes into contact with the vertical frame <NUM> or the case <NUM> or is located on the rear in the traveling direction of the vertical frame <NUM> or the case <NUM>. For example, the restricting member <NUM> is formed to be elastically deformable. For example, the restricting member <NUM> is a rubber plate, a brush, or the like.

That is, if the cart <NUM> moves rearward, the vertical frame <NUM> or the power reception device <NUM> comes into contact with the restricting member <NUM>, whereby the restricting member <NUM> restricts movement of the cart <NUM> until a sufficient force is applied to the cart <NUM>. For example, if the user moves the cart <NUM> rearward, the restricting member <NUM> is elastically deformable to permit movement of the cart <NUM>. In the power feeding device <NUM>, both of the protrusion <NUM> and the restricting member <NUM> may be provided. For example, in the power feeding device <NUM>, an upper surface present in the rear wheel guide <NUM> of the base <NUM> may be recessed to restrict rearward movement of the cart <NUM>.

In the example described above, the power feeding device <NUM> includes the plurality of supporting members <NUM>. However, the power feeding device <NUM> is not limited to this. For example, the power feeding device <NUM> may include a single supporting member <NUM>. The single supporting member <NUM> may support the plurality of power transmission devices <NUM>. For example, such a single supporting member <NUM> includes, as illustrated in <FIG>, a single base <NUM> long in the traveling direction of the cart <NUM>. A plurality of rear wheel guides <NUM> and a plurality of wall sections <NUM> are provided on the base <NUM>. The single supporting member <NUM> may include a single base <NUM> long in the traveling direction of the cart <NUM> and a single wall section. The plurality of rear wheel guides <NUM> may be provided on the base <NUM>. The plurality of engaging sections <NUM> may be provided in the single wall section.

In the example described above, a part of the rear wheel guide <NUM> extends along the traveling direction to restrict movement in the width directions of the rear wheel <NUM> (the cart <NUM>). However, the rear wheel guide <NUM> is not limited to this. That is, the rear wheel guide <NUM> only has to be able to restrict movement in the width directions of the rear wheel <NUM>. A part of the rear wheel guide <NUM> may incline and extend with respect to the traveling direction.

In the example described above, the power feeding device <NUM> includes the cart guide <NUM>, the plurality of power transmission devices <NUM>, and the single or the plurality of supporting members <NUM>. However, the power feeding device <NUM> is not limited to this. For example, as illustrated in <FIG> and <FIG>, the power feeding device <NUM> includes, in addition to the cart guide <NUM>, the plurality of power transmission devices <NUM>, and the single or the plurality of supporting members <NUM>, and an adjustment plate <NUM> for adjusting the posture of the cart <NUM>. At least the rear wheel <NUM> disposed on the base <NUM> and the rear wheel <NUM> on the opposite side can be disposed on the adjustment plate <NUM>. The adjustment plate <NUM> is set to height equal to or larger than the height of the upper surface of the base <NUM>.

As illustrated in <FIG> and <FIG>, the upper surface of the adjustment plate <NUM> is set to be higher than the upper surface of the base <NUM>. The rear wheel <NUM> of the cart <NUM> runs on the base <NUM> and the adjustment plate <NUM>, whereby, as illustrated in <FIG> and <FIG>, the cart <NUM> inclines to lower the side where the power reception device <NUM> is provided. In an example illustrated in <FIG> and <FIG>, the height of the adjustment plate <NUM> is set to be <NUM> larger than the height of the base <NUM> to incline the cart <NUM> to the left side approximately <NUM> degrees. Since the cart <NUM> is inclined by the adjustment plate <NUM> towards the lower the power reception device <NUM> side in this way, the power feeding device <NUM> can prevent the cart <NUM> from moving in a direction in which the power reception device <NUM> separates from the power transmission device <NUM>. Accordingly, the power feeding device <NUM> can prevent the power reception device <NUM> from separating from the power transmission device <NUM> and thus stopping power feeding. If the cart <NUM> is inclined by the adjustment plate <NUM>, the cart <NUM> does not move in the direction away from the power transmission device <NUM>. Therefore, the power feeding device <NUM> need not include the rear wheel guides <NUM> in this example.

In some examples, the height of the adjustment plate <NUM> may be set to the same height as the height of the base <NUM>. If the base <NUM> and the adjustment plate <NUM> have the same height, the cart <NUM> does not incline one or the other. Therefore, it is possible to prevent the cart <NUM> from moving in the direction in which the power reception device <NUM> separates from the power transmission device <NUM>.

If the cart <NUM> is inclined by the adjustment plate <NUM>, it is likely that the front wheels <NUM> may float above the floor surface illustrated in <FIG>. Therefore, if the front wheels <NUM> lift away from the floor surface, as indicated by an alternate long and two short dashes line in <FIG>, the power feeding device <NUM> may further include plate-like members <NUM> that fill the gaps between the floor surface and the front wheels <NUM>. Such members <NUM> can be disposed in regions where the front wheels <NUM> of the plurality of carts <NUM> are to be disposed. If lifting heights from the floor surface are different for the left and right front wheels <NUM>, the heights of the members <NUM> can be set to have different heights.

In an example described above, the two casters <NUM> forming the rear wheels are provided on the vertical frame <NUM>. The two casters <NUM> forming the front wheels are provided on the horizontal frame <NUM>. However, a cart <NUM> is not limited to this arrangement. For example, the four casters <NUM> may be provided on the horizontal frame <NUM>. The configuration of the cart main body <NUM> can be adjusted as appropriate.

In an example described above, a plurality of engaging sections <NUM> are provided. However, the engaging sections <NUM> can be set as appropriate so long as the engaging sections <NUM> can guide the position of the power reception device <NUM> in the traveling direction of the cart <NUM>. For example, a single engaging device <NUM> may be provided in the wall section <NUM>. The engaging sections <NUM> may be deformable in the rearward direction along the traveling direction of the cart <NUM>. That is, the engaging sections <NUM> may support the power reception device <NUM> just during frontward movement along the traveling direction of the cart <NUM>. If the power reception device <NUM> comes into contact with the engaging sections <NUM> in rearward movement along the traveling direction of the cart <NUM>, the engaging sections <NUM> may be formed so as not to hinder the movement of the cart <NUM>.

Claim 1:
A cart charging system comprising a cart charging station for providing power to carts with a power reception device (<NUM>) mounted thereon and comprising at least one cart (<NUM>), the cart charging station (<NUM>) comprising:
a supporting member (<NUM>);
a power transmission device (<NUM>) positioned on the supporting member (<NUM>) such that a power transmission surface of the power transmission device (<NUM>) faces a power receiving surface of a power reception device (<NUM>) on the cart (<NUM>) at the cart charging station (<NUM>), the power transmission device (<NUM>) configured to transmit electric power to the power reception device (<NUM>) in a non-contact manner;
an engaging member (<NUM>) configured to engage the power reception device (<NUM>) of the cart (<NUM>) and restrict movement of the cart (<NUM>) in a frontward direction and width directions of the cart (<NUM>);
characterized in that the cart charging station (<NUM>) comprises a restricting member (<NUM>) configured to restrict movement of the power reception device (<NUM>) of the cart (<NUM>) in a rearward direction of the cart (<NUM>).