JP2013050323A - Electronic watch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic watch that ensures excellent antenna performance while suppressing an increase in a thickness dimension or the number of components of the watch.SOLUTION: A wrist watch with GPS 1 includes: a case 10; an antenna 26 arranged inside the case 10 and receiving satellite signals from a position information satellite; and a receiving substrate 211 arranged inside the case 10. The case 10 includes: a rear lid 12 formed of a conductive member; and a body 11 provided separately from or integrally with the rear lid 12. The rear lid 12 includes a wall part 122 that surrounds a receiving circuit 24 mounted on the receiving substrate 211.

Description

  The present invention relates to an electronic timepiece that receives a satellite signal transmitted from a position information satellite such as a GPS satellite and obtains the current date and time.

An electronic timepiece having a wireless function for receiving a satellite signal (radio wave) transmitted from a position information satellite such as a GPS (Global Positioning System) satellite and acquiring a current time is known (for example, see Patent Document 1).
In the electronic timepiece of Patent Document 1, a C-type loop antenna with a dielectric substrate is arranged around the display unit.

JP 2009-168656 A

By the way, when a wireless function is mounted on a small electronic timepiece such as a wristwatch, a circular (ring-shaped) antenna is advantageous in terms of space as a configuration of the antenna. When such an antenna is mounted, the receiving circuit for processing the received satellite signal is preferably arranged on the center side.
However, when the current consumption in the receiving circuit increases, radiation noise generated in the receiving circuit increases, and the reception sensitivity at the antenna may be reduced.
For this reason, generally, the reception sensitivity is prevented from lowering by surrounding the receiving circuit with a shield plate that shields radiation noise. However, by providing the shield plate, there is a problem that the thickness of the timepiece becomes thick or the number of parts increases and the assembling work becomes complicated.

  An object of the present invention is to provide an electronic timepiece capable of ensuring good antenna performance while suppressing an increase in the thickness dimension and the number of parts of the timepiece.

  An electronic timepiece according to the present invention includes a case, an antenna that is disposed inside the case and receives a satellite signal from a position information satellite, and a receiving substrate that is disposed inside the case. A back cover formed of a conductive member, and a body provided separately or integrally with the back cover, and the back cover is provided with a wall portion surrounding a circuit mounted on the receiving substrate. It is characterized by being.

In such an invention, a wall portion surrounding a circuit that becomes a radiation noise source for a circuit mounted on a receiving substrate, for example, an antenna such as a receiving circuit or a power circuit, is provided on a back cover formed of a conductive member. Provided.
Since the periphery of the circuit of the receiving substrate is shielded by the wall portion of the back cover, radiation noise emitted from the circuit is shielded, and the reception sensitivity of the antenna can be prevented from being lowered. Moreover, since the back cover has a function of a shield plate, it is not necessary to provide a shield plate separately. For this reason, the increase in the thickness dimension and the number of parts of the electronic timepiece can be suppressed.
Here, the antenna of the present invention includes, for example, a C-shaped antenna in which a part of the ring is missing, in addition to an annular ring that is continuous in the circumferential direction. Further, the display by the display unit includes display by a pointer, display by various display panels such as a liquid crystal display pal or an organic EL (Electro Luminescence) display panel, and the like.

In the electronic timepiece of the invention, it is preferable that a receiving circuit is provided as a circuit mounted on the receiving substrate, and the back cover is provided with a wall portion surrounding the receiving circuit.
A receiving circuit for processing a satellite signal received by the antenna is mounted on the receiving board. When the current consumption of this receiving circuit increases, radiation noise generated in the receiving circuit also increases, which affects reception at the antenna.
In the present invention, since the periphery of the receiving circuit mounted on the receiving board is shielded by the wall portion of the back cover, radiation noise emitted from the receiving circuit can be shielded, and a decrease in receiving sensitivity of the antenna can be prevented.

In the electronic timepiece of the invention, it is preferable that a power circuit is provided as a circuit mounted on the receiving substrate, and the back cover is provided with a wall portion surrounding the power circuit.
When a power supply circuit is mounted on the receiving board, the power supply circuit includes a DC / DC converter and the like, and a large amount of radiation noise is generated.
In the present invention, since the periphery of the power supply circuit mounted on the receiving board is shielded by the wall portion of the back cover, radiation noise emitted from the power supply circuit can be shielded, and a decrease in reception sensitivity of the antenna can be prevented.
In addition, when the receiving circuit and the power supply circuit are mounted on the receiving substrate, the wall portion is preferably configured to surround both the receiving circuit and the power supply circuit. In this case, radiation noise generated in the receiving circuit and the power supply circuit can be shielded by the wall portion of the back cover, so that it is possible to more effectively prevent the antenna receiving sensitivity from being lowered.

In the electronic timepiece according to the aspect of the invention, the receiving substrate is disposed inside the case with the circuit facing the back cover, and the wall portion is in contact with a ground pattern provided on the receiving substrate. The circuit mounted on the receiving board is preferably surrounded by the receiving board, the wall portion of the back cover, and the back cover.

  In such an invention, since the tip of the wall portion of the back cover is brought into contact with the ground pattern provided on the receiving board, the circuit mounted on the receiving board is surrounded by the back cover and the receiving board. It becomes a state. For this reason, the radiation noise which generate | occur | produces in the circuit of a receiving board can be shielded reliably. In particular, since the tip of the wall of the back cover is in contact with the ground pattern of the receiving board, the back cover can also be maintained at the ground potential, radiation noise can be effectively shielded, and the antenna reception sensitivity can be further reduced. Can be prevented.

  In the electronic timepiece according to the aspect of the invention, the case includes the case back and a case body separate from the case back, and the case back includes a screw having an annular threaded portion that is screwed into the case. Preferably, the wall portion is formed in a cylindrical shape, and the center position of the wall portion is the same position as the center of the screw portion.

  In such an invention, the cylindrical wall portion is formed on the screw-type back cover, and the wall portion and the screw portion of the back cover are provided concentrically. When removing, the center of the wall is not displaced even if the case back is rotated. For this reason, if the circuit used as a radiation noise source is arrange | positioned in the center of a trunk | drum, it can accommodate reliably inside a wall part.

In the electronic timepiece according to the aspect of the invention, it is preferable that a battery disposed inside the wall portion is provided.
When the battery is arranged outside the wall portion of the back cover, it must be arranged in a space between the wall portion and the trunk, and the size and shape of the battery are greatly restricted. On the other hand, in the present invention, since the battery is arranged inside the wall portion of the back cover, if the size of the wall portion is appropriately set, the size and shape of the battery are not restricted, and the inside of the watch is The configuration can be easily designed.

Schematic which shows the electronic timepiece which concerns on this invention. 1 is a schematic sectional view showing an electronic timepiece according to a first embodiment of the present invention. The schematic sectional drawing which shows the electronic timepiece of 2nd embodiment of this invention. The schematic sectional drawing which shows the electronic timepiece of 3rd embodiment of this invention. The schematic sectional drawing which shows the electronic timepiece of 4th embodiment of this invention.

[First embodiment]
Hereinafter, a GPS (Global Positioning System) wristwatch according to a first embodiment of the electronic timepiece of the invention will be described with reference to the drawings.

{Configuration of wristwatch with GPS}
As shown in FIG. 1, the GPS wristwatch 1 includes a time display unit including a dial 2 and hands 3.
The pointer 3 includes a second hand, a minute hand, an hour hand, and the like, and is driven via a drive mechanism including a step motor and a gear train, which will be described later.

The GPS wristwatch 1 receives satellite signals from GPS satellites 5 that are a plurality of position information satellites orbiting the earth in a predetermined orbit, acquires satellite time information, and corrects internal time information. It is configured to be able to.
The GPS satellite 5 is an example of the position information satellite in the present invention, and a plurality of GPS satellites 5 exist above the earth. Currently, about 30 GPS satellites 5 orbit.
Further, the GPS wristwatch 1 is provided with a crown 6 and buttons 7 and 8 for external operation.

{Internal configuration of GPS wristwatch}
Next, the internal configuration of the GPS wristwatch 1 will be described.
As shown in FIG. 2, the GPS wristwatch 1 includes a case 10 and a movement 20 that is accommodated in the case 10 and drives the hands 3.

The case 10 includes a ring-shaped body 11 and a back cover 12 that closes one opening (the lower side in FIG. 2) of the body 11.
The body 11 and the back cover 12 are made of a metal material such as BS (brass), SUS (stainless steel), or a titanium alloy. Although details will be described later, the back cover 12 is a screw type connected to the body 11 by a screw structure.

The movement 20 is for performing time display by the hands 3 and receiving a signal from the GPS satellite 5, and includes a circuit board 21 on which circuit elements (IC and the like) for processing the time display and the GPS function are mounted, and hands 3 And a drive mechanism 22 including a gear train, and a battery 23 for supplying electric power thereto.
The circuit elements mounted on the circuit board 21 include a receiving circuit 24 and a control circuit 25. The receiving circuit 24 processes the satellite signal received from the GPS satellite 5 by the GPS antenna 26.

  The control circuit 25 controls the drive mechanism 22 and generates at least one of time information and positioning information from the satellite signal received by the receiving circuit 24.

  The battery 23 may be a primary battery or a secondary battery such as a lithium ion battery. When a secondary battery is used, it is preferable to incorporate a power generation mechanism for charging a secondary battery such as a solar panel.

The dial 2 described above is disposed on the opening surface 11 </ b> A of the trunk 11.
The dial 2 is made of a metal material such as BS (brass), SUS (stainless steel), or a titanium alloy. The surface of the dial 2 is subjected to surface treatment by painting, plating, sputtering, or the like in order to improve the appearance.
The pointer 3 described above is arranged on the front side (upper side in FIG. 2) of the dial 2 and the movement 20 is arranged on the rear side (lower side in FIG. 2) of the dial 2. In the movement 20, the driving mechanism 22, the circuit board 21, and the battery 23 are arranged in layers in this order from the dial 2 side to the back cover 12 side.

The GPS wristwatch 1 includes a GPS antenna 26 that is disposed along the outer periphery of the dial 2 and receives satellite signals from the GPS satellite 5.
The GPS antenna 26 is covered with the dial ring 15.
The dial ring 15 has an inclined surface (conical surface) whose inner periphery faces the dial plate 2, and an indicator scale is printed on the inclined surface in 60 divisions.

A bezel 13 is disposed on the outer periphery of the dial ring 15, and a cover glass 14 that covers the surface side of the dial 2 and the hands 3 is disposed on the inner side of the bezel 13.
The bezel 13 is formed in a ring shape in which the outer periphery is continuous with the outer periphery of the barrel 11, and is connected to the barrel 11 of the case 10 by means of a fitting structure with irregularities formed on the opposing surfaces or means such as double-sided adhesive tape or adhesive. Has been.

In the GPS wristwatch 1, the case 11 and the case back 12 of the case 10 are each formed of a metal material having an excellent texture, and an appropriate surface finish is applied to the surface thereof.
The dial ring 15 and the bezel 13 are made of a nonconductive material such as synthetic resin or ceramics, and the cover glass 14 is also made of a nonconductive glassy material. Each of these elements is also given a surface finish that takes into account the texture.
By using such a material, the dial ring 15, the bezel 13, and the cover glass 14 on the surface side (upper side in FIG. 2) from the dial 2 are all non-conductive materials, and these are the outer periphery on the front side of the dial 2. It does not affect the GPS antenna 26 installed in as an electromagnetic shield.

{GPS antenna}
The GPS antenna 26 includes a ring-shaped dielectric base material 26A having a rectangular cross section, and an antenna electrode 26B is formed on the surface thereof.
As a dielectric material used for the dielectric substrate 26A, it is desirable to use a dielectric ceramic having a high dielectric constant when importance is placed on high antenna performance, and a synthetic resin material is used when importance is attached to cost reduction. Can do.
The dielectric base material 26A has a length that allows a predetermined antenna length to be obtained according to the radio wave to be used in consideration of the characteristics of the conductive material described above.

The antenna electrode 26B is formed by bending a conductive metal plate such as copper and attaching it to the surface (upper side in FIG. 2) of the dielectric base 26A. The antenna electrode 26B may be formed by patterning the surface of the dielectric base material 26A by electroless plating.
The antenna electrode 26 </ b> B is electrically connected to the signal terminal of the circuit board 21 through the connector 27.

The circuit board 21 has a multilayer board configuration including a first board 211 and a second board 212. The first substrate 211 and the second substrate 212 are electrically connected by a connector 28.
A receiving circuit 24 for processing a received signal from the GPS satellite 5 is attached to the back side (the lower side in FIG. 2) of the first substrate 211. Further, although not shown, a power supply circuit such as a DC / DC converter is also attached to the first substrate 211. The first substrate 211 constitutes the receiving substrate of the present invention.
On the other hand, the control circuit 25 is attached to the back side of the second substrate 212.

  In the present embodiment, a ground pattern (not shown) is formed on the circuit board 21 (the first board 211 and the second board 212). The ground pattern is formed in an appropriate shape so as to obtain as large an area as possible while removing and insulating portions such as through holes connecting other layers of the circuit board 21.

{Back cover}
The back cover 12 is a screw-type back cover having a screw portion 121 on the outer peripheral surface. The back cover 12 is provided with a wall portion 122 projecting in a cylindrical shape concentric with the screw portion 121. That is, the center of the cylindrical wall portion 122 is formed at the same position as the center of the screw portion 121.
In the wall 122, the tip (upper end) of the wall 122 is in contact with the ground pattern of the first substrate (receiving substrate) 211 in a state where the screw 121 is screwed into the screw 11 </ b> B of the body 11. The receiving circuit 24 is disposed in a space surrounded by the wall portion 122.

That is, the receiving circuit 24 is surrounded by the back cover 12 and the wall part 122 on the lower surface and the side surface on the back cover 12 side, and is surrounded by the first substrate 211 that is the reception board on the dial plate 2 side. For this reason, even if noise is emitted from the receiving circuit 24, the noise is shielded by the back cover 12 of the conductive member and the first substrate 211, and does not leak outside.
The battery 23 is disposed between the wall portion 122 of the back cover 12 and the body 11.

  Since the case 10 including the back cover 12 and the trunk 11 is made of metal, it is possible to avoid the influence on the GPS antenna 26 by the user's arm to be worn. That is, if the case 10 is a plastic case, it is not preferable because the resonance frequency of the antenna fluctuates due to the influence of nearby arms and when it is not worn, resulting in a difference in performance. However, since the case 10 is made of metal, the effect of the arm can be avoided by the shielding effect, and in this embodiment, there is almost no difference in antenna characteristics between when the sensor is mounted and when it is not mounted, and stable reception performance can be obtained.

{Operational effects of the first embodiment}
According to the first embodiment as described above, the following effects can be obtained.
A wall 122 surrounding the periphery of the reception circuit 24 is provided on the back cover 12 formed of a conductive member.
For this reason, even if radiation noise is emitted from the receiving circuit 24, it is shielded by the wall portion 122 of the back cover 12, and it is possible to prevent the reception sensitivity of the GPS antenna 26 from being lowered.

Furthermore, since the tip of the wall 122 of the back cover 12 is in contact with the ground pattern of the first substrate 211, the receiving circuit 24 is surrounded by the back cover 12 and the first substrate 211. . For this reason, radiation noise from the receiving circuit 24 is reliably shielded, and it is possible to reliably prevent the reception sensitivity of the GPS antenna 26 from being lowered.
Furthermore, since the back cover 12 also has a function of a shield plate that shields radiation noise of the receiving circuit 24, it is not necessary to provide a separate shield plate. For this reason, the increase in the thickness dimension of a timepiece and the number of parts can be suppressed.

  The wall portion 122 of the back cover 12 is provided so as to be concentric with the screw portion 121. Therefore, when the screw-type back cover 12 is attached to or removed from the body 11, the position of the wall 122 relative to the body 11 or the movement 20 does not change even if the back cover 12 is rotated. For this reason, if the receiving circuit 24 is disposed at the center position of the body 11 and the back cover 12 is attached, the receiving circuit 24 can be reliably disposed inside the wall portion 122.

[Second Embodiment]
Next, a GPS wristwatch according to a second embodiment of the present invention will be described.
FIG. 3 is a schematic sectional view of a GPS wristwatch 1A according to the second embodiment of the present invention. In addition, about the structure similar to said 1st embodiment, the same code | symbol is attached | subjected and description is simplified or abbreviate | omitted.

In the first embodiment, the battery 23 is disposed outside the wall portion 122 of the back cover 12. In contrast, in the GPS wristwatch 1A of the second embodiment, the battery 23 is also arranged on the inner peripheral side of the wall portion 122A. That is, in the second embodiment, the wall portion 122A is formed on the outer peripheral side of the first embodiment, and the battery 23 can be stored inside the wall portion 122A.
Note that the battery 23 is electrically connected to a first substrate 211 as a receiving substrate by a connector 29. In addition, the first substrate 211 and the second substrate 212 are stacked and electrically connected. The control circuit 25 is attached to the front surface side (upper side in FIG. 3) of the second substrate 212.

  In the second embodiment, the same effect as that of the first embodiment described above can be obtained, and the battery 23 is also housed in the wall portion 122A of the back cover 12. Therefore, the size and shape of the battery 23 can be adjusted. Restrictions are reduced and general button-shaped batteries can also be used.

[Third embodiment]
Next, a GPS wristwatch according to a third embodiment of the present invention will be described.
FIG. 4 is a schematic cross-sectional view of a GPS wristwatch 1B according to a third embodiment of the present invention. In addition, about the structure similar to said each embodiment, the same code | symbol is attached | subjected and description is simplified or abbreviate | omitted.

In the first embodiment, the screw-type back cover 12 is used. On the other hand, the GPS wristwatch 1B according to the third embodiment is configured such that the back cover 12B is screwed to the body 11.
Specifically, the back cover 12B has a flange portion 123 that protrudes in a bowl shape from the outer peripheral edge and is screwed to the lower end portion (lower side in FIG. 4) of the body 11. A wall 122B whose tip is in contact with the ground pattern of the first substrate 211 is provided on the surface (upper side in FIG. 4) of the back cover 12B. The wall portion 122B does not need to be formed in a cylindrical shape and concentric with the screw portion 121 like a screw-type back cover. For this reason, even when the receiving circuit 24 is arranged so as to be shifted from the center of the body 11 to the outside due to the storage relationship with the battery 23, the wall 122B can be formed so as to surround the receiving circuit 24.

In the third embodiment, as in the first embodiment described above, the receiving circuit 24 is surrounded by the back cover 12B, the wall 122B of the back cover 12B, and the first substrate 211, which is a reception substrate. Can be prevented and the reception sensitivity of the GPS antenna 26 can be prevented from lowering.
Furthermore, in the third embodiment, since the back cover 12B is screwed to the body 11, the wall 122B can be provided at a position displaced from the center of the back cover 12B. Further, the planar shape of the wall 122B is not limited to a circle but may be a rectangle or the like. For this reason, the freedom degree of the arrangement position of the receiving circuit 24 increases, and the planar shape of the wall part 122B can be designed according to the planar shape of the receiving circuit 24. For this reason, the arrangement space of the battery 23 provided outside the wall portion 122B can be increased.

[Fourth embodiment]
Next, a GPS wristwatch according to a fourth embodiment of the present invention will be described.
FIG. 5 is a schematic sectional view of a GPS wristwatch 1C according to a fourth embodiment of the present invention. In addition, about the structure similar to said each embodiment, the same code | symbol is attached | subjected and description is simplified or abbreviate | omitted.

In each of the above embodiments, the case 11 and the back covers 12 and 12B are separate bodies. However, the GPS wristwatch 1C of the fourth embodiment includes a one-piece type case 10C in which the case 11C and the back cover 12C are integrated. Used.
Specifically, the case 10C includes a cylindrical body 11C and a back cover 12C that is integrally provided at one end of the body 11C in the axial direction and closes one end surface of the body 11C, and has a bottomed cylindrical shape. Is formed.
A wall 122C is provided on the back cover 12C. On the inner peripheral edge at the tip of the wall portion 122C, a stepped portion is provided that is engaged with and screwed to the outer peripheral edge of the first substrate 211 as a receiving substrate. Wall portion 122C is electrically connected to the ground pattern of first substrate 211 engaged with the stepped portion.

In the fourth embodiment, as in the first embodiment described above, the receiving circuit 24 is surrounded by the back cover 12C, the wall 122C of the back cover 12C, and the first substrate 211, which is a receiving substrate. Can be shielded, and the reception sensitivity of the GPS antenna 26 can be prevented from lowering. In particular, since the receiving circuit 24 is surrounded by the back cover 12C and the first substrate 211, radiation noise from the receiving circuit 24 can be reliably shielded, and the reception sensitivity of the GPS antenna 26 is reduced. It can be surely prevented.
Furthermore, in the fourth embodiment, since the trunk 11C and the back cover 12C are integrated, a GPS wristwatch 1C having excellent waterproof properties can be configured.

[Other Embodiments]
In addition, this invention is not limited to said each embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention.
For example, the GPS wristwatches 1, 1 </ b> A, 1 </ b> B, and 1 </ b> C are analog clocks that indicate the time with the hands 3. A digital clock may be used. Furthermore, the present invention is not limited to a wristwatch, and may be applied to various watches such as a pocket watch.

Moreover, in each said embodiment, although wall part 122,122A, 122B, 122C was made to contact | abut to the ground pattern of the 1st board | substrate 211 which is a receiving board | substrate, it does not necessarily need to contact | abut. However, it is preferable to make it contact in that the shielding effect can be enhanced.
Further, in each of the embodiments, the periphery of the reception circuit 24 mounted on the first substrate 211 that is the reception substrate is surrounded by the wall portions 122, 122A, 122B, 122C of the back cover 12, 12B, 12C. The power supply circuit mounted on the reception board may be enclosed, or the reception circuit 24 and the power supply circuit may be enclosed. That is, according to the present invention, among the circuits mounted on the receiving board, various circuits that are radiation noise sources with respect to the antenna 26 are surrounded by the wall portions 122, 122A, 122B, 122C of the back cover 12, 12B, 12C. It is only necessary to shield the radiation noise and prevent the reception sensitivity of the antenna 26 from being lowered.

Further, although the GPS satellite 5 has been described as an example of the position information satellite, the position information satellite according to the present invention is not limited to the GPS satellite 5, but other Galileo (EU), GLONASS (Russia), Hokuto (China), etc. It may be a global navigation satellite system (GNSS), or a position information satellite that transmits satellite signals including time information such as geostationary satellites such as SBAS and quasi-zenith satellites.
Further, the present invention is not limited to the radio wave reception of satellite signals from such position information satellites, and can also be used as a short-range wireless reception device for a circularly polarized wireless tag using, for example, a 900 MHz band.
Furthermore, it can be used not only for receiving circularly polarized waves but also for receiving linearly polarized radio waves.

  In addition, the specific configuration and form in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

  1, 1A, 1B, 1C ... GPS wristwatch (electronic watch), 3 ... hand, 10, 10C ... case, 11, 11C ... trunk, 12, 12B, 12C ... back cover, 121 ... screw part, 122, 122A, 122B, 122C ... wall portion, 20 ... movement, 21 ... circuit board, 211 ... first board (receiving board), 212 ... second board, 23 ... battery, 24 ... receiving circuit, 25 ... control circuit, 26 ... GPS antenna .

Claims (6)

Case and
An antenna arranged inside the case and receiving a satellite signal from a position information satellite;
A receiving substrate disposed inside the case,
The case has a back cover formed of a conductive member, and a body provided separately or integrally with the back cover,
An electronic timepiece characterized in that the back cover is provided with a wall portion surrounding a circuit mounted on the receiving substrate. The electronic timepiece according to claim 1,
A receiving circuit as a circuit mounted on the receiving substrate,
An electronic timepiece characterized in that the back cover is provided with a wall portion surrounding the receiving circuit. The electronic timepiece according to claim 1 or 2,
A power circuit is provided as a circuit mounted on the receiving board,
An electronic timepiece characterized in that the back cover is provided with a wall portion surrounding the power supply circuit. The electronic timepiece according to any one of claims 1 to 3,
The receiving board is disposed inside the case with the circuit facing the back cover,
The wall portion is in contact with a ground pattern provided at a tip of the receiving substrate,
An electronic timepiece characterized in that a circuit mounted on the receiving board is surrounded by the receiving board, a wall portion of the back cover, and the back cover. The electronic timepiece according to any one of claims 1 to 4,
The case includes the back cover, and the back cover and a separate body,
The back cover is a screw-type back cover having an annular threaded portion that is screwed into the body.
The wall portion is formed in a cylindrical shape, and the center position of the wall portion is the same position as the center of the screw portion. The electronic timepiece according to any one of claims 1 to 5,
An electronic timepiece comprising a battery disposed inside the wall.

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