Patent Description:
Most of related small or medium electronic devices such as uninterruptible power devices, power supplies, network routers, network access points, set-top boxes, barebone computers are of flat cuboid shape, and the electronic devices may be laid flat or kept up-right according to the installed space. Some small or medium electronic devices are provided with a display for displaying the status information of the electronic device, and the display may be disposed cooperatively with an operation interface for operating the electronic device. However, the display cannot be rotated corresponding to various directions of placements of the electronic device. For the various directions of placements of the electronic device, a related electronic device is provided with a square display, and the display can be disposed in a direction corresponding to the placement of the electronic device when the electronic device is installed. However, it is inconvenient to detach the display, and inner circuit may be exposed through a hole for installing the display and cause an electric shock to a user when the display is detached. In addition, more compact design and higher cost may be necessary in order to satisfy the requirements of safety regulations.

In view of the above drawbacks, the inventor proposes this disclosure based on his expert knowledge and elaborate researches in order to solve the problems of related art.

<CIT> discloses a measurement device providing a graphical user interface (GUI) to a user on a remote terminal comprising at least one first processor; and at least one first memory including one or more first sequences of instructions to perform the steps of transmitting a GUI displaying a at least one of a first, a second, a third, and a fourth image in response to at least one of a voltage characteristic, a current characteristic, and a load characteristic obtained from the user through the GUI on the remote terminal. Then, the measurement device stores in a memory the at least one of the voltage characteristic, the current characteristic, and the load characteristic.

<CIT> discloses an electrical appliance device conting a knob which has a knob front assembly with a front cover assembly, a knob bracket, and a display module assembly disposed between the front cover assembly and the knob bracket, and a knob rear assembly including a circuit board and a hollow rotary encoder. The rotary encoder is mounted on the circuit board. The electrical appliance device further has a panel with an opening. The knob front assembly at least partially passes through the opening such as to be mounted to the knob rear assembly.

<CIT> discloses a state display device of an uninterruptible power supply, excellent in workability in product manufacturing, easy and excellent in workability in replacing or adding a storage battery part. Thus (see <FIG>), at a disk-shaped plate face central position, a power converter unit and a display element for displaying an operational state of a storage battery unit are mounted. Along a peripheral edge part of the disk-shaped plate face, two substantially circular arc-shaped guides <NUM> having a convex cross section are formed. A rotary member <NUM>, which is a disk-shaped plate face, on which a fixing claw <NUM> of an inverse L-shaped in cross-section is formed so as to be erected at the disk-shaped plate face between the guides <NUM>, is included. A support member, coupled to a power converter unit housing container <NUM>, to which a circumference of the rotary member <NUM> is fitted, in which a circular hole <NUM> is formed so that the rotary member <NUM> can be rotated, four quarter arc-shaped guides <NUM> having a convex cross-section are formed on the same circumference along an edge part of the circular hole <NUM>, two fixing claws <NUM> included in the rotary member <NUM> are fitted to four positioning parts existing between the quarter arc-shaped guides <NUM>, for supporting the rotary member <NUM> so as to be capable of rotating by <NUM> degrees, is included.

This disclosure is directed to an electronic device having a casing, a circular frame, and a display as being defined by claim <NUM>. Accordingly, the casing has a panel arranged on a side of the casing and a plurality of side plates adjacent to a periphery of the panel, a circular opening is defined on the panel, and a first fixing structure is arranged on an internal edge of the circular opening. The circular frame is rotatably arranged on the circular opening and closes the circular opening, a second fixing structure is arranged on an external edge of the circular frame, the second fixing structure disposed on the periphery of the circular frame is slidable with the circular frame along a circumferential direction in the first fixing structure, and the circular frame is configured to be rotatable relative to the circular opening and the second fixing structure is limited by the first fixing structure. The display is embedded in the circular frame and exposed on the panel. Further, the casing is configured to be placeable on any one of the plurality of side as bottom of the casing, and the circular frame is rotatable for adjusting a direction of the display according to the placing position of the casing on any one of the plurality of side plates as the bottom so as to display an information which can be squarely watched, wherein the first fixing structure comprises a sliding latch and the second fixing structure correspondingly comprises a curve slot arranged concentrically with the circular frame, the second fixing structure comprises another sliding latch and the first fixing structure correspondingly comprises another curve slot arranged concentrically with the circular opening, wherein the another sliding latch is extended of a curved, the sliding latches respectively snap the curve slots to fix the circular frame on the casing; and wherein the sliding latches are slidable in the curve slots respectively when the circular frame is rotated in the circular opening.

Any one of the side plates can be configured as a bottom of the casing. When any one of the side plates is configured as a bottom of the casing, a placing position is defined corresponding to each of the side plates as the bottom, and the circular frame is rotatable to make a direction of the display be corresponding to the placing position so as to display an information which can be squarely watched.

According to the electronic device of this disclosure, the circular frame protrudes from the panel. An operating interface is arranged on the circular frame. The casing is of a cuboid shape and the panel is of a rectangular shape.

According to the electronic device of this disclosure, the first fixing structure may have a sliding latch, the second fixing structure may have a curve slot arranged concentrically with the circular frame, and the sliding latch snaps the curve slot. The second fixing structure may have a sliding latch, the first fixing structure may have a curve slot arranged concentrically with the circular opening, and the sliding latch snaps the curve slot. Alternatively, the first fixing structure may have a sliding latch and the second fixing structure may correspondingly have a curve slot arranged concentrically with the circular frame, the second fixing structure may have another sliding latch and the first fixing structure may correspondingly have another curve slot arranged concentrically with the circular opening, and each sliding latches correspondingly snap each respective curve slot.

According to the electronic device of this disclosure, a first positioning structure is arranged on the internal edge of the circular opening, a second positioning structure is arranged on the external edge of the circular frame, the circular frame is rotatable with respect to the circular opening to one of a plurality of predetermined positions corresponding to the placing position, the first positioning structure and the second positioning structure block each other along a circumferential direction of the circular opening when the circular frame is located in any one of the predetermined positions. When the circular frame is located at one of the predetermined positions, the first positioning structure and the second positioning structure are buckled with each other along the circumferential direction of the circular opening. When the circular frame is located at any one of the predetermined positions, the first positioning structure and the second positioning structure are buckled with each other along an axial direction of the circular opening. The first positioning structure may have a spherical tenon, and the second positioning structure may have a positioning hole buckled with the spherical tenon. Alternatively, the second positioning structure may have a spherical tenon, and the first positioning structure may have a positioning hole buckled with the spherical tenon.

According to the electronic device of this disclosure, the circular frame is rotatable from any one of the predetermined positions to another predetermined position through an angle in multiples of <NUM> degrees.

According to the electronic device of this disclosure, the first positioning structure and the second positioning structure respectively have a block, when the circular frame is located at one of the predetermined positions, two blocks abut against each other and block each other unidirectionally along a circumferential direction of the circular opening.

According to the electronic device of this disclosure, the display is rotatably arranged in the circular opening of the casing via the circular frame. Accordingly, the display may be rotatable according to various placing positions of the casing to facilitate the usage for a user.

The features of the disclosure believed to be novel are set forth with particularity in the appended claims. The disclosure itself, however, may be best understood by reference to the following detailed description of the disclosure, which describes a number of exemplary embodiments of the disclosure, taken in conjunction with the accompanying drawings, in which:.

The technical contents of this disclosure will become apparent with the detailed description of embodiments accompanied with the illustration of related drawings as follows. It is intended that the embodiments and drawings disclosed herein are to be considered illustrative rather than restrictive.

According to a first non-claimed example, useful to understand the invention shown in <FIG>, an electronic device having a casing <NUM>, a circular frame <NUM> and a display <NUM> is provided.

The casing <NUM> is of a cuboid shape, a panel <NUM> is arranged on a side of the casing <NUM>, and the panel <NUM> is of a rectangular shape. The casing <NUM> has a plurality of side plates adjacent to a periphery of the panel <NUM>, the casing <NUM> may be placed in a manner of any one of a plurality of placing positions corresponding to one of the side plates <NUM>, <NUM>. The casing <NUM> according to this embodiment has two side plates <NUM>, <NUM> as the bottom corresponding to two placing positions. Accordingly, the casing <NUM> may be placed in a manner of the first placing position, and the first side plate <NUM> is configured as the bottom. Moreover, the casing <NUM> may stand in a manner of the second placing position as shown in <FIG>, and the second side plate <NUM> is configured as the bottom. A circular opening <NUM> is defined on the panel <NUM>, and a first fixing structure <NUM> is arranged on an internal edge of the circular opening <NUM>.

According to <FIG>, the circular frame <NUM> may be a circular ring, a circular plate or a cylinder, an exterior profile of the circular frame <NUM> is matched with an interior profile of the circular opening <NUM>, the circular frame <NUM> is rotatably arranged in the circular opening <NUM> to close the circular opening <NUM>. According to this embodiment, the circular frame <NUM> may be protruded from the panel <NUM> to facilitate the usage for a user of rotating the circular frame <NUM>, but this disclosure is not limited to this embodiment. For example, the circular frame <NUM> may be disposed in a coplanar manner with the panel <NUM> or be recessed in the circular opening <NUM>. A second fixing structure <NUM> is arranged at an external edge of the circular frame <NUM>, the second fixing structure <NUM> is annularly arranged at a circular external edge of the circular frame <NUM> corresponding to the first fixing structure <NUM>, and the second fixing structure <NUM> is slidable with the circular frame <NUM> and limited in the first fixing structure <NUM>. Therefore, the circular frame <NUM> is limited at the circular opening <NUM> of the panel <NUM> of the casing <NUM>. Furthermore, the second fixing structure <NUM> on the periphery of the circular frame <NUM> is slidable along a circumferential direction in the first fixing structure <NUM>, and the circular frame <NUM> is rotatable relative to the circular opening <NUM>. According to this embodiment, the second fixing structure <NUM> is annularly arranged on a circular profile defined by the circular external edge of the circular frame <NUM> corresponding to the first fixing structure <NUM>, but this disclosure is not limited to this embodiment.

Specific structures of the first fixing structure <NUM> and the second fixing structure <NUM> are described as follows. According to this embodiment, the first fixing structure <NUM> has a curve slot <NUM>, the second fixing structure <NUM> has a sliding latch <NUM> arranged concentrically with the circular frame <NUM>, and the sliding latch <NUM> is latched to the curve slot <NUM>. When the circular frame <NUM> rotates in the circular opening <NUM>, the sliding latch <NUM> is slidable in the curve slot <NUM> to avoid the interference to a rotation of the circular frame <NUM>.

According to <FIG>, the display <NUM> is embedded in the circular frame <NUM> and exposed on the panel <NUM>, the display <NUM> may be provided with an electric connector <NUM> for electrically connecting to a main board (not shown in figures) of an electronic device via a cable (not shown in figures) to display information related to status of the electronic device, and an operating interface <NUM> electrically connected with the main board is arranged on the circular frame <NUM> for an operation to the electronic device by the user. The display <NUM>, the electric connector <NUM> and the operating interface <NUM> may be arranged on a sub circuit board <NUM>. The type of the operating interface <NUM> is not limited in this disclosure. For example, the operating interface <NUM> may be physical keys or a touch screen integrated with the interface display <NUM>.

According to <FIG>, in order to limit the rotation of the circular frame <NUM>, a first positioning structure <NUM> is arranged on the internal edge of the circular opening <NUM>, a second positioning structure <NUM> is correspondingly arranged at the external edge of the circular frame <NUM>. The circular frame <NUM> is rotatable relative to the circular opening <NUM> to one of the predetermined positions, and the circular frame <NUM> may be rotated from any one of the predetermined positions to another predetermined position through an angle in multiples of <NUM> degrees. When the circular frame <NUM> is located at any one of the predetermined positions, the first positioning structure <NUM> and the second positioning structure <NUM> may block each other along a circumferential direction of the circular opening <NUM> to prevent the circular frame <NUM> from an unexpected displacement.

The circular frame <NUM> is limited by the first positioning structure <NUM> and the second positioning structure <NUM> to be rotatable relative to the circular opening <NUM> between the first predetermined position shown in <FIG> and the second predetermined position shown in <FIG>. According to <FIG>, when the casing <NUM> is placed at a flat status and the first side plate <NUM> is configured as the bottom, the circular frame <NUM> may be correspondingly rotated to the first predetermined position, so that an operator may squarely watch the display <NUM>. According to <FIG>, when the casing <NUM> is kept in an up-right status and the second side plate <NUM> is configured as the bottom, the circular frame <NUM> may be correspondingly rotated to the second predetermined position, so that the operator may squarely watch the display <NUM>.

The casing <NUM> is rotated through an angle in multiples of <NUM> degrees when being rotated to shift between the plurality of flat and up-right placing positions. According to the aforementioned embodiment, the two side plates <NUM>, <NUM> are arranged adjacently and perpendicularly to each other, and the circular frame <NUM> may be rotated between the two predetermined positions in an angle of <NUM> degrees correspondingly. However, the rotating angle is not limited in this disclosure. For example, the casing <NUM> may have two side plates parallel with each other <NUM>, <NUM>(or <NUM>, <NUM>) used for the bottom, and the circular frame <NUM> may be rotated between the two predetermined positions in an angle of <NUM> degrees correspondingly. Furthermore, number of the predetermined positions is not limited in this disclosure either. For example, the casing <NUM> may have three adjacent side plates <NUM>, <NUM>, <NUM> used for the bottom, the circular frame <NUM> may be rotated to three predetermined positions, and the rotating angles of <NUM> degrees are disposed between adjacent predetermined positions correspondingly.

According to the electronic device of this disclosure, the first positioning structure <NUM> and the second positioning structure <NUM> may respectively have a block <NUM>/<NUM>, when the circular frame <NUM> is located at a predetermined position which is at an end of a rotatable range, the pair of blocks <NUM>/<NUM> abut against each other and stop each other unidirectionally along the circumferential direction of the circular opening <NUM> so as to prevent the cable from a damage caused by over twisting when the circular frame <NUM> is rotated out of a predetermined range.

Furthermore, the first positioning structure <NUM> may have a spherical tenon <NUM>, and the second positioning structure <NUM> may have a positioning hole <NUM> for snapping the spherical tenon <NUM>. When the circular frame <NUM> is located at any one of the predetermined positions in the rotatable range, the spherical tenon <NUM> snaps the positioning hole <NUM> along a direction parallel with a central axis of the circular opening <NUM>, so that the circular frame <NUM> is positioned by the first positioning structure <NUM> and the second positioning structure <NUM> to be prevented from an unexpected rotation. The aforementioned spherical tenon <NUM> and the positioning hole <NUM> may be exchanged in position, namely the second positioning structure <NUM> may have a spherical tenon <NUM> and the first positioning structure <NUM> may have a positioning hole <NUM> for snapping the spherical tenon <NUM>. Multiple spherical tenons <NUM> or multiple positioning holes <NUM> may be arranged according to an arrangement of the predetermined positions. A function of the spherical tenon <NUM> is that the spherical tenon <NUM> may slip out of the snapped positioning hole <NUM> to allow the rotation of the circular frame <NUM> when the user rotates the circular frame <NUM> with a sufficient torque.

According to the second embodiment of this disclosure, an electronic device having a casing <NUM>, a circular frame <NUM> and a display <NUM> is provided. The second embodiment is similar to the first embodiment shown in <FIG>.

The casing <NUM> is of a cuboid shape, a panel <NUM> is arranged on a side of the casing <NUM>, and the panel <NUM> is of a rectangular shape. A circular opening <NUM> is defined on the panel <NUM>, and a first fixing structure <NUM> is arranged at an internal edge of the circular opening <NUM>.

According to <FIG>, the circular frame <NUM> may be a circular ring, a circular plate or a cylinder, an exterior profile of the circular frame <NUM> is matched with an interior profile of the circular opening <NUM>, the circular frame <NUM> is rotatably arranged in the circular opening <NUM> to close the circular opening <NUM>. According to this embodiment, the circular frame <NUM> may be protruded from the panel <NUM> to facilitate the usage for the user of rotating the circular frame <NUM>, but this disclosure is not limited to this embodiment. For example, the circular frame <NUM> may be disposed in a coplanar manner with the panel <NUM> or be recessed in the circular opening <NUM>. A second fixing structure <NUM> is arranged at an external edge of the circular frame <NUM>, the second fixing structure <NUM> snaps the first fixing structure <NUM> to fix the circular frame <NUM> on the casing <NUM>.

Specific structures of the first fixing structure <NUM> and the second fixing structure <NUM> are described as follows. According to this embodiment, the first fixing structure <NUM> has a sliding latch <NUM>, and the second fixing structure <NUM> correspondingly has a curve slot <NUM> arranged concentrically with the circular frame <NUM>. The second fixing structure <NUM> further has a sliding latch <NUM>, the sliding latch <NUM> is extended of a curved shape according to this embodiment. The first fixing structure <NUM> correspondingly has a curve slot <NUM> arranged concentrically with the circular opening <NUM>. The sliding latches <NUM>, <NUM> respectively snap each curve slot <NUM>/<NUM> to fix the circular frame <NUM> on the casing <NUM>. When the circular frame <NUM> is rotated in the circular opening <NUM>, each sliding latch <NUM>/<NUM> is slidable in each corresponding curve slot <NUM>/<NUM> to avoid the interference to a rotation of the circular frame <NUM>.

The display <NUM> is embedded in the circular frame <NUM> and exposed on the panel <NUM>, the display <NUM> may be provided with an electric connector <NUM> for electrically connecting to a main board (not shown in figures) of an electronic device via a cable (not shown in figures) to display information related to status of the electronic device, and an operating interface <NUM> electrically connected with the main board is arranged on the circular frame <NUM> for an operation to the electronic device by the user. The display <NUM>, the electric connector <NUM> and the operating interface <NUM> may be arranged on a sub circuit board <NUM>. The type of the operating interface <NUM> is not limited in this disclosure. For example, the operating interface <NUM> may be physical keys or a touch screen integrated with the interface display <NUM>.

In order to limit the rotation of the circular frame <NUM>, a first positioning structure <NUM> is arranged on the internal edge of the circular opening <NUM>, a second positioning structure <NUM> is correspondingly arranged at the external edge of the circular frame <NUM>. According to the placing position of the casing <NUM>, the circular frame <NUM> may be correspondingly rotated to one of a plurality of predetermined positions relative to the circular opening <NUM>, and the circular frame <NUM> may be rotated from one of the predetermined positions to another predetermined position through an angle in multiples of <NUM> degrees. According to this embodiment, one of the predetermined positions is shown in <FIG>, and another predetermined position is shown in <FIG>. According to <FIG>, when the circular frame <NUM> is located at any one of the predetermined positions, the first positioning structure <NUM> and the second positioning structure <NUM> may block each other along a circumferential direction of the circular opening <NUM> to prevent the circular frame <NUM> from an unexpected displacement.

According to the electronic device of this disclosure shown in <FIG>, the first positioning structure <NUM> and the second positioning structure <NUM> may respectively have a block <NUM>/<NUM>, when the circular frame <NUM> is located at a predetermined position which is at an end of a rotatable range, the pair of blocks <NUM>/<NUM> abut against each other and block each other unidirectionally along the circumferential direction of the circular opening <NUM> so as to prevent the cable from a damage caused by over twisting when the circular frame <NUM> is rotated out of a predetermined range.

According to the third embodiment of this disclosure, an electronic device having a casing <NUM>, a circular frame <NUM> and a display <NUM> is provided. The third embodiment is similar to the first embodiment shown in <FIG>.

According to <FIG>, the casing <NUM> is of a cuboid shape, a panel <NUM> is arranged on a side of the casing <NUM>, and the panel <NUM> is of a rectangular shape. A circular opening <NUM> is defined on the panel <NUM>, and a first fixing structure <NUM> is arranged at an internal edge of the circular opening <NUM>.

The circular frame <NUM> may be a circular ring, a circular plate or a cylinder, an exterior profile of the circular frame <NUM> is matched with an interior profile of the circular opening <NUM>, the circular frame <NUM> is rotatably arranged in the circular opening <NUM> to close the circular opening <NUM>. According to this embodiment, the circular frame <NUM> may be protruded from the panel <NUM> to facilitate the usage for the user of rotating the circular frame <NUM>, but this disclosure is not limited to this embodiment. For example, the circular frame <NUM> may be disposed in a coplanar manner with the panel <NUM> or be recessed in the circular opening <NUM>. A second fixing structure <NUM> is arranged at an external edge of the circular frame <NUM>, the second fixing structure <NUM> snaps the first fixing structure <NUM> to fix the circular frame <NUM> on the casing <NUM>.

Specific structures of the first fixing structure <NUM> and the second fixing structure <NUM> are described as follows. According to this embodiment, the second fixing structure <NUM> has a sliding latch <NUM>, the first fixing structure <NUM> has a curve slot <NUM> arranged concentrically with the circular opening <NUM>, the sliding latch <NUM> snaps the corresponding curve slot <NUM> so as to fix the circular frame <NUM> on the casing <NUM>. When the circular frame <NUM> is rotated in the circular opening <NUM>, the sliding latch <NUM> is slidable in each corresponding curve slot <NUM> to avoid the interference to a rotation of the circular frame <NUM>.

In order to limit the rotation of the circular frame <NUM>, a first positioning structure <NUM> is arranged on the internal edge of the circular opening <NUM>, a second positioning structure <NUM> is correspondingly arranged at the external edge of the circular frame <NUM>, the circular frame <NUM> may be correspondingly rotated to one of a plurality of predetermined positions relative to the circular opening <NUM>, and the circular frame <NUM> may be rotated from any of the predetermined positions to another predetermined position through an angle in multiples of <NUM> degrees. When the circular frame <NUM> is located at any one of the predetermined positions, the first positioning structure <NUM> and the second positioning structure <NUM> may block each other along a circumferential direction of the circular opening <NUM> to prevent the circular frame <NUM> from an unexpected displacement.

According to this embodiment, two ends of a rotatable range of the circular frame <NUM> respectively have a predetermined position, the first positioning structure <NUM> and the second positioning structure <NUM> may be buckled with each other along the circumferential direction of the circular opening <NUM> when the circular frame <NUM> is located at any one of the predetermined positions. The second fixing structure <NUM> and the second positioning structure <NUM> are disposed on the same rod extended from the circular frame <NUM> according to this embodiment, the sliding latch <NUM> of the second fixing structure <NUM> is disposed on a tip of the rod, the sliding latch <NUM> may be of a spherical shape to facilitate the buckling to the curve slot <NUM>. Specifically, the first positioning structure <NUM> has a latched notch <NUM>, the latched notch <NUM> has at least one neck opening 133a. According to this embodiment, two latched notches <NUM> are disposed corresponding to the two predetermined positions shown in <FIG> and <FIG>, the two latched notches <NUM> respectively communicate with two ends of the curve slot <NUM> through the neck openings 133a, and the second positioning structure <NUM> has a cylinder <NUM> inserted in the curve slot <NUM> for buckling the latched notch <NUM>. The cylinder <NUM> is formed on a middle segment of the rod and is movable along the curve slot <NUM> with the rotation of the circular frame <NUM>. When the circular frame <NUM> is located at any one of the predetermined positions, the cylinder <NUM> may snap into the neck opening 133a of the latched notch <NUM> correspondingly so as to be fixed in the latched notch <NUM> to position the circular frame <NUM>. When the user rotates the circular frame <NUM> with a sufficient torque, the cylinder <NUM> has a curved surface so that the cylinder <NUM> may slip out of the snapped latched notch <NUM> to allow the rotation of the circular frame <NUM>. In this embodiment, alternatively, a latched notch <NUM> may be additionally arranged at a middle segment of the curve slot <NUM>, and an angle in multiples of <NUM> degrees is defined between the adjacent latched notches <NUM> relative to a center of the circular opening <NUM>.

Claim 1:
An electronic device, comprising:
a casing (<NUM>), comprising a panel (<NUM>) arranged on a side thereof and a plurality of side plates (<NUM>, <NUM>) adjacent to a periphery of the panel (<NUM>), a circular opening (<NUM>) defined on the panel (<NUM>), and a first fixing structure (<NUM>) arranged on an internal edge of the circular opening (<NUM>);
a circular frame (<NUM>), rotatably arranged in the circular opening (<NUM>) and closing the circular opening (<NUM>), a second fixing structure (<NUM>) arranged on an external edge of the circular frame (<NUM>), the second fixing structure (<NUM>) disposed on the periphery of the circular frame (<NUM>) is slidable with the circular frame (<NUM>) along a circumferential direction in the first fixing structure (<NUM>), and the circular frame (<NUM>) is configured to be rotatable relative to the circular opening and the second fixing structure (<NUM>) is limited by the first fixing structure (<NUM>); and
a display (<NUM>), embedded in the circular frame (<NUM>) and exposed on the panel (<NUM>),
wherein the casing (<NUM>) is configured to be placeable on any one of the plurality of side plates (<NUM>, <NUM>) as a bottom of the casing (<NUM>),
and the circular frame (<NUM>) is rotatable for adjusting a direction of the display (<NUM>) according to the placing position of the casing (<NUM>) on any one of the plurality of side plates (<NUM>, <NUM>) as the bottom so as to display an information which can be squarely watched,
wherein the first fixing structure (<NUM>) comprises a sliding latch (<NUM>) and the second fixing structure (<NUM>) correspondingly comprises a curve slot (<NUM>) arranged concentrically with the circular frame (<NUM>), the second fixing structure (<NUM>) comprises another sliding latch (<NUM>) and the first fixing structure (<NUM>) correspondingly comprises another curve slot (<NUM>) arranged concentrically with the circular opening (<NUM>),
wherein the another sliding latch (<NUM>) is extended of a curved, the sliding latches (<NUM>, <NUM>) respectively snap the curve slots (<NUM>, <NUM>) to fix the circular frame (<NUM>) on the casing (<NUM>); and
wherein the sliding latches (<NUM>, <NUM>) are slidable in the curve slots (<NUM>, <NUM>) respectively when the circular frame (<NUM>) is rotated in the circular opening (<NUM>).