Patent Description:
A known conventional ceiling concealed air-conditioning apparatus includes a suction grille attached to a decorative panel so that it can be opened and detached. To avoid deterioration in design of the decorative panel, typically, a slide part is provided at an end of the suction grille and the slide part is manually moved to allow the suction grille to be engaged with the decorative panel. Another known example of the ceiling concealed air-conditioning apparatus incorporates a spring mechanism into a slide mechanism to save labor in opening and closing or detaching and attaching the suction grille and also integrates a locking element and a plate spring to reduce the number of components (e.g., see Patent Literature <NUM>). <CIT> discloses an indoor unit for an air-conditioning apparatus with: a protruding piece protruding horizontally from a decorative panel toward an opening of an indoor-unit main body; an engagement member, which is provided on a back surface of a suction panel at a position of being opposed to the protruding piece to be slidable with respect to the protruding piece in a front-and-back direction of the indoor unit, and is configured to be guided by the protruding piece of the decorative panel to be locked to the protruding piece; plate springs, which are provided at both ends of the engagement member which are orthogonal to a sliding direction of the engagement member, and extend in directions opposite to each other to be orthogonal to the sliding direction; and at least two spring support portions, which are formed on the suction panel, and are configured to sandwich both end surfaces of each of the plate springs at different positions, in which, when the engagement member slides in a retreating direction of the engagement member by the protruding piece, the each of the plate springs urges the engagement member toward the protruding piece with the at least two spring support portions as supporting points.

The decorative panel is typically made of resin. Accordingly, the component integrating a slide part and a spring part is also typically made of resin. Use of such resin components may cause backlash between the components during assembly of the decorative panel due to variations in molded resin components, which are in turn due to variations in factors such as thermal stress and liquidity during molding. Also, there is a concern for durability as a stress is applied on a spring fulcrum when the spring function takes place.

The present invention has been made in view of the above problems and aims to provide a ceiling concealed air-conditioning apparatus that can reduce backlash during assembly due to molding variations, reduce deterioration in operability due to such backlash, and improve durability by increasing the number of fulcrums for exertion of the spring function and thereby dispersing stress on the fulcrums.

The invention is set out in the in the appended set of claims.

The ceiling concealed air-conditioning apparatus of an embodiment of the present invention includes: a body containing a heat exchanger and a fan and including an opening port at the bottom; a decorative panel disposed below the body, the decorative panel being configured to cover a periphery of the opening port of the body; and a suction grille including, on one edge thereof, a rotary shaft that can be attached to the decorative panel, the suction grille being configured to cover the opening port of the body so as to allow the opening port to be opened, wherein the suction grille includes: a locking element mounted on the suction grille and configured to be locked with the decorative panel; plate springs on respective sides of the locking element perpendicular to a sliding direction of the locking element, the plate springs extending vertically in opposite directions to each other; and spring supports provided to the suction grille and configured to support both end faces of the respective plate springs at different positions, the plate springs of the locking element include a long plate spring and a short plate spring having different lengths, and the long plate spring and the short plate spring are placed such that the long plate spring engages the decorative panel first. Accordingly, even when the locking element is placed in a direction vertical to the rotary shaft of the suction grille for attachment to the decorative panel, backlash is less likely to occur and smooth engagement is enabled, thereby improving operability.

<FIG> is a perspective view of a ceiling concealed air-conditioning apparatus according to an embodiment of the present invention when it is installed in a ceiling surface and viewed from below. <FIG> is a schematic sectional view of the inside of the body shown in <FIG>. <FIG> is a perspective view of the suction grille shown in <FIG> when it is opened.

As shown in <FIG>, the body <NUM> of the ceiling concealed air-conditioning apparatus contains a heat exchanger <NUM> and a fan <NUM> and includes a decorative panel <NUM> covering a periphery of an opening port at the bottom and a suction grille <NUM> covering the opening port of the body <NUM> defined by the decorative panel <NUM> such that the opening port can be opened. The decorative panel <NUM> and the suction grille <NUM> of the ceiling concealed air-conditioning apparatus are exposed from a ceiling plate <NUM>, and the body <NUM> is installed inside the ceiling plate <NUM>. The body <NUM> of the ceiling concealed air-conditioning apparatus is connected to an outdoor unit (not shown) with refrigerant pipes.

The heat exchanger <NUM> of the body <NUM> of the ceiling concealed air-conditioning apparatus exchanges heat between air, which is to be air-conditioned, and refrigerant. The heat exchanger <NUM> is an indoor heat exchanger forming a part of a refrigerant circuit comprised of a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and the indoor heat exchanger successively connected to each other by pipes. The heat exchanger <NUM> serves as a condenser during a heating operation to condense and liquefy the refrigerant, and serves as an evaporator during a cooling operation to evaporate and gasify the refrigerant.

The body <NUM> is formed of a cuboid metal plate with an opening port at the bottom. The suction grille <NUM> has a rectangular shape along a longitudinal direction of the body <NUM>. The suction grille <NUM> includes, at its respective ends in a transverse direction, air inlets <NUM> each composed of multiple grilles and formed lengthwise. The suction grille <NUM> is formed by resin molding. The decorative panel <NUM> is fixed to the body <NUM>. The decorative panel <NUM> is formed with an air outlet <NUM> on one side of the air inlets <NUM>. A pivotable wind vane for changing air blow directions is attached to the air outlet <NUM>.

The suction grille <NUM> is, at its edge on one of the air inlets <NUM>, supported by a rotary shaft <NUM> attached to the body <NUM> so as to be able to rotate. The suction grille <NUM> is capable of opening and closing the opening port of the body <NUM> by rotating about the rotary shaft <NUM>. A pair of locking elements <NUM> are attached to respective edges of the suction grille <NUM> extending at right angles from the edge of the suction grille <NUM> supported by the rotary shaft <NUM>. The locking elements <NUM> hold the suction grille <NUM> closed when the opening port of the body <NUM> is closed by the suction grille <NUM>.

The suction grille <NUM> is configured to open and close to enable replacement of an air filter <NUM> (described later) and cleaning inside the body <NUM>. The air filter <NUM> is attached so that it can be removed, to a side of each air inlet <NUM> facing the inside of the body <NUM>, which is the rear side of the air inlet <NUM>. The air filter <NUM> collects dust contained in air entering the body <NUM> through each air inlet <NUM>.

The fan <NUM> includes, for example, a cross-flow fan placed on a wind path <NUM> communicating with the air outlet <NUM>, and a motor (not shown) placed on one side of the cross-flow fan in the axial direction thereof. The heat exchanger <NUM> is placed in a V-shape between the fan <NUM> and the air inlets <NUM>.

In the above configured ceiling concealed air-conditioning apparatus, driving the fan <NUM> causes indoor air to be suctioned from the air inlets <NUM> of the suction grille <NUM> and enter the body <NUM> through the air filter <NUM>. The air having entered the body <NUM> is further suctioned by the fan <NUM> toward the heat exchanger <NUM>, where the air exchanges heat with refrigerant flowing in the heat exchanger <NUM>. The air having undergone the heat exchange is sent to the wind path <NUM> and then blown into the room from the air outlet <NUM>.

With reference to <FIG>, a description will be given on the structure of the above locking element <NUM>.

<FIG> is an enlarged view of one of the locking elements shown in <FIG>. <FIG> is a plan view showing the locking element of <FIG> when it is mounted on the suction grille. <FIG> is a plan view showing the locking element of <FIG> when it is supported by the suction grille so as to be able to slide. <FIG> is a plan view showing the locking element of <FIG> when it is retracted.

As shown in <FIG>, a long plate spring 31a and a short plate spring 31b each formed in a plate shape by resin molding are attached to the locking element <NUM>. The long plate spring 31a and the short plate spring 31b extend at right angles in an advancing and retracting direction and are opposite to each other. The locking element <NUM> includes a locking part <NUM>, a guide part <NUM>, an operation part <NUM>, a pair of slide parts in between the guide part <NUM>, and a long hole defined by the pair of slide parts.

The locking part <NUM> is a protrusion protruding upward further than a distal end of the guide part <NUM> of the locking element <NUM>. The guide part <NUM> protrudes upward from the top face at each end of the locking element <NUM>. The guide part <NUM> has an inclined surface. The long plate spring 31a and the short plate spring 31b extend opposite to each other and at right angles from respective ends of the locking element <NUM> perpendicular to its sliding direction. The operation part <NUM> extends downward from a rear part of the locking element <NUM>. The slide parts receive a screw <NUM>. The long hole extends lengthwise in the front-back direction of the locking element <NUM> and allows for insertion of the screw <NUM>.

As shown in <FIG>, the locking element <NUM> resides on the air inlet <NUM> side of the suction grille <NUM> and rests on a support frame extending to the inside of the air inlet <NUM> from the grille located at the end of the air inlet <NUM>. The support frame is formed with a screw hole to receive the above-described screw <NUM> and supports the locking element <NUM> so that the locking element <NUM> can slide in the longitudinal direction of the long hole.

Each of the long plate spring 31a and the short plate spring 31b extending from the respective sides of the locking element <NUM> is sandwiched between a main rib 15a and an auxiliary rib 15b provided on two respective grilles on the end side of the plural grilles forming the air inlet <NUM>. Each of the long plate spring 31a and the short plate spring 31b is held at two points by these ribs 15a, 15b. This can correct any deformation or variation of the long and short plate springs 31a, 31b in an advancing direction <NUM> or a retracting direction <NUM> that may occur during molding of the long and short plate springs 31a, 31b. The main rib 15a and the auxiliary rib 15b are spring supports integrally molded with the suction grille <NUM> and hold both sides of each of the long plate spring 31a and the short plate spring 31b at different positions. The main rib 15a and the auxiliary rib 15b are positioned such that those holding the long plate spring 31a are farther from the locking part <NUM> than those holding the short plate spring 31b are.

When the locking element <NUM> of <FIG> is moved in a direction (retracting direction) indicated by the solid arrow shown in <FIG> by manual operation of the operation part <NUM>, each of the long and short plate springs 31a, 31b bends in the retracting direction <NUM> around the main rib 15a and the auxiliary rib 15b as fulcrums against the elastic force. Upon release of the hand from the operation part <NUM>, the locking element <NUM> is energized by the elastic force of the long and short plate springs 31a, 31b in a direction (advancing direction <NUM>) indicated by the dashed arrow, returning to the state shown in <FIG>.

When the locking element <NUM> shown in <FIG> moves in the retracting direction <NUM>, the long and short plate springs 31a, 31b extending at right angles bend and thereby generate spring reaction force in the advancing direction <NUM> around the main rib 15a and the auxiliary rib 15b as fulcrums. Using the main rib 15a and the auxiliary rib 15b as fulcrums can disperse reaction force on the fulcrum parts generated by the spring reaction force.

The spring reaction force generated in the advancing direction <NUM> can be adjusted by changing the distance from the locking part <NUM> to the main rib 15a and the auxiliary rib 15b, and enlarging this distance leads to reduced reaction force. Accordingly, the locking element <NUM> is mounted on the suction grille <NUM> such that the long plate spring 31a engages the decorative panel <NUM> first when the suction grille <NUM> is attached to the decorative panel <NUM>. Since the spring force of the long plate spring 31a is weak, the locking part <NUM> does not move toward the disengaging side or slant when the engagement takes place. Thus, placing the locking element <NUM> such that its long plate spring 31a resides closer to the rotary shaft <NUM> for opening and closing of the suction grille <NUM> allows for stable engagement and fixing of the locking element <NUM> to the decorative panel <NUM> and smooth attachment of the suction grille <NUM>.

With reference to <FIG>, a description will now be made on the locking function when the suction grille <NUM> is opened and closed.

<FIG> is a sectional view showing a positional relationship between the locking element and the decorative panel when the suction grille of <FIG> is lifted close to the decorative panel. <FIG> is a sectional view showing a positional relationship between the locking element and the decorative panel when the suction grille of <FIG> is about to be closed into the decorative panel. <FIG> is a sectional view showing a positional relationship between the locking element and the decorative panel when the suction grille of <FIG> has been closed into the decorative panel. <FIG> is a sectional view showing a positional relationship between the locking element and the decorative panel when the locking element of <FIG> is retracted.

The decorative panel <NUM> includes, on its side wall facing the locking element <NUM>, a protrusion piece protruding horizontally toward the opening port of the body <NUM>. The protrusion piece has the length equal to the width of the locking element <NUM> and includes at its distal end a decorative panel-side guide part 13a. The guide part 13a has an inclined surface parallel to the inclined surface of the suction grille-side guide part <NUM> of the locking element <NUM>. The protrusion piece is provided inside of the design surface of the decorative panel <NUM>. Thus, no protrusion is required to be provided on the suction grille <NUM>, which is operated to open and close by the user, and this ensures safety.

As shown in <FIG>, when the suction grille <NUM> is lifted close to the decorative panel <NUM>, the locking element <NUM> comes under the decorative panel-side guide part 13a. Further lifting the suction grille <NUM> causes the inclined surface of the suction grille-side guide part <NUM> of the locking element <NUM> to contact the inclined surface of the decorative panel-side guide part 13a, as shown in <FIG>. Lifting the locking element <NUM> with these inclined surfaces contacting each other results in the locking element <NUM> being guided by the inclined surfaces. At this time, the slide parts of the locking element <NUM> retract in the direction (retracting direction <NUM>) indicated by the solid arrow.

In this case, each of the long and short plate springs 31a, 31b on the respective sides of the locking element <NUM> bends in the retracting direction <NUM> around the main rib 15a and the auxiliary rib 15b as fulcrums against the elastic force. In this state, when the suction grille <NUM> is pushed into the decorative panel <NUM>, the locking element <NUM> advances in the direction (advancing direction <NUM>) indicated by the dashed arrow by the elastic force of the long and short plate springs 31a, 31b, as shown in <FIG>, resulting in the suction grille-side locking part <NUM> of the locking element <NUM> being locked into a decorative panel-side fixed locking part 13b. By locking of the locking element <NUM>, the suction panel <NUM> closes the opening port of the body <NUM>.

On the other hand, when the suction panel <NUM> closing the opening port of the body <NUM> is opened, the operation part <NUM> of the locking element <NUM> is manually pulled in the direction indicated by the solid arrow, as shown in <FIG>. This moves the locking part <NUM> of the locking element <NUM> away from the fixed locking part 13b of the decorative panel <NUM>, releasing the lock. By release of the lock, the suction panel <NUM> opens the opening port of the body <NUM> by rotating around the rotary shaft <NUM>.

In the present embodiment as described above, the long and short plate springs 31a, 31b extending from the respective sides of the locking element <NUM> have different spring lengths and are also held by the main rib 15a and the auxiliary rib 15b at different distances from the locking part <NUM>. This can, by leveraging the property that the bending spring force against the elastic force varies depending on the length of the spring, absorb any engagement displacement of the locking element <NUM> on the suction grille <NUM> in the transverse direction, improving operability.

Also, using the main rib 15a and the auxiliary rib 15b formed on the suction panel <NUM> as fulcrums can disperse the load applied when the plate spring exerts its spring function. This can increase the durability of the plate spring molded from a resin material. Further, arranging the main rib 15a and the auxiliary rib 15b face-to-face allows for mounting the plate spring while correcting variations in its shape, and this can absorb the backlash of the plate spring.

Claim 1:
A ceiling concealed air-conditioning apparatus comprising:
a body (<NUM>) containing a heat exchanger (<NUM>) and a fan (<NUM>) and including an opening port at a bottom;
a decorative panel (<NUM>) disposed below the body (<NUM>), the decorative panel (<NUM>) being configured to cover a periphery of the opening port of the body (<NUM>); and
a suction grille (<NUM>) including, on one edge thereof, a rotary shaft (<NUM>) that can be attached to the decorative panel (<NUM>), the suction grille (<NUM>) being configured to cover the opening port of the body (<NUM>) so as to allow the opening port to be opened, wherein
the suction grille (<NUM>) includes:
a locking element (<NUM>) mounted on a rear side of the suction grille (<NUM>) so that it can slide and configured to be locked with the decorative panel (<NUM>);
plate springs (31a, 31b) on respective sides of the locking element (<NUM>) perpendicular to a sliding direction of the locking element (<NUM>), the plate springs (31a, 31b) extending vertically in opposite directions to each other; and
spring supports (15a, 15b) provided to the suction grille (<NUM>) and configured to support both end faces of the respective plate springs (31a, 31b) at different positions,
the plate springs (31a, 31b) of the locking element (<NUM>) include a long plate spring (31a) and a short plate spring (31b) having different lengths, and
the long plate spring (31a) and the short plate spring (31b) are placed such that the long plate spring (31a) is engaged first when the suction grille (<NUM>) is attached to the decorative panel (<NUM>).