Patent Description:
In general, an air conditioner is an electronic appliance for maintaining indoor air at pleasant temperature using a cooling cycle of refrigerants. The air conditioner includes an indoor unit, an outdoor unit, and a refrigerant pipe, wherein the indoor unit includes a heat exchanger, a blower fan, etc. and is installed indoor, the outdoor unit includes a heat exchanger, a blower fan, a compressor, a condenser, etc. and is installed outdoor, and the refrigerant pipe connects the indoor unit to the outdoor unit and circulates refrigerants.

The air conditioner can be classified into a stand type air conditioner in which an indoor unit is installed on the floor, a wall-mounted air conditioner in which an indoor unit is mounted on a wall, and a ceiling type air conditioner in which an indoor unit is mounted on a ceiling, according to places where the indoor unit is installed. In the ceiling type air conditioner, the indoor unit is embedded into or hung on the ceiling.

Since the indoor unit of the ceiling type air conditioner is mounted on the ceiling, an inlet for inhaling indoor air, and an outlet for discharging air heat-exchanged through the heat exchanger to the indoor space are disposed in the lower part of the main body. The indoor unit of the ceiling type air conditioner can be classified into a <NUM>-way type with a single outlet and a <NUM>-way type with four outlets forming a quadrangle, according to the number of outlets.

Generally, the indoor unit of the air conditioner includes a blade for adjusting a direction in which heat-exchanged air is discharged, in the outlet. The blade is rotatably coupled with one part of the outlet. The blade is coupled with a motor at one end, and receives a rotatory force generated by the motor to rotate.

The blade is configured to be rotatable in both directions. The blade rotates in both directions in the outlet to adjust the movement direction of heat-exchanged air in the up-down direction. However, since the blade is directly connected to the motor, vibrations and noise may be generated when the motor transfers a rotatory force to the blade. Also, when the indoor unit of the ceiling type air conditioner is installed non-horizontally to the ceiling, a connection axis along which the blade is coupled with the motor is misaligned so that vibration sound of the motor and friction sound of the blade may be loudly generated.

<CIT> relates to an indoor unit of an air conditioner comprising a main body, an air outlet, a wind deflection plate including rotating shafts, a motor including a rotation shaft, and a joint member interposed between the rotating shaft of the wind direction plate and the rotating shaft of the motor.

An aspect of the present invention is to provide an indoor unit of an air conditioner having an improved structure for preventing vibrations and noise of a blade due to vibrations of a motor when the blade rotates, and a blade unit applied to the indoor unit.

In accordance with the present invention, there is provided a blade unit according to claim <NUM>. Features of the invention are set out in the dependent claims. Other examples that do no fall within the scope of the claims relate to exemplary embodiments of the present disclosure.

The indoor unit of the air conditioner according to a technical concept of the present invention, and the blade unit applied to the indoor unit can prevent vibrations and noise of the blade due to vibrations of the motor when the blade rotates.

Hereinafter, preferred embodiments of the present invention will be described in detail.

Also, hereinafter, for convenience of description, an indoor unit of a ceiling type air conditioner will be described as an example. However, a blade unit according to an embodiment of the present invention can be applied to an indoor unit of another type air conditioner, such as an indoor unit of a stand type air conditioner and an indoor unit of a wall-mounted air conditioner.

<FIG> is an exploded perspective view showing an indoor unit of an air conditioner, and a blade unit applied to the indoor unit, and <FIG> is a cross-sectional view schematically showing an indoor unit of an air conditioner according to an embodiment of the present invention.

Referring to <FIG> and <FIG>, an indoor unit <NUM> of an air conditioner may include a main body <NUM> configured to be hung on or embedded into a ceiling, and a bottom panel <NUM> coupled with the lower part of the main body <NUM>.

The main body <NUM> may be in the shape of a box, and may include a heat exchanger <NUM> configured to heat-exchange inhaled indoor air with refrigerants, a blower fan <NUM> configured to make air flow forcedly, and a control unit <NUM> configured to control operations of the indoor unit <NUM> of the air conditioner.

The main body <NUM> may include an upper plate 10a and side plates 10b forming the front, back, left, and right appearances of the air conditioner. The main body <NUM> may include a scroll part <NUM> configured to guide air heat-exchanged through the heat exchanger <NUM> towards an outlet <NUM>.

In the lower part of the main body <NUM>, an inlet <NUM> configured to inhale indoor air to the inside of the main body <NUM>, and the outlet <NUM> configured to discharge heat-exchanged air to the indoor space are provided. In the outlet <NUM>, a wind-direction control member <NUM> may be provided to adjust the left-right direction of discharged air.

The heat exchanger <NUM> may include a tube 12b through which refrigerants flow, and a plurality of heat-exchange pins 12b contacting the tube 12a to widen a heat transfer area. The heat exchanger <NUM> may be inclined to be at nearly right angles to the direction of air flow.

Between the heat-exchanger <NUM> and the inlet <NUM>, a guide rib <NUM> may be provided to guide indoor air inhaled into the inside of the main body <NUM> through the inlet <NUM> towards the heat exchanger <NUM>. The guide rib <NUM> may be inclined to be at nearly right angles to the position of the heat exchanger <NUM>.

Below the heat exchanger <NUM>, a drain cover <NUM> may be provided to collect condensation water generated from the heat exchanger <NUM>. Condensation water collected in the drain cover <NUM> may be drained to the outside through a drainage hose (not shown).

The blower fan <NUM> may be rotated by a driving force of a driving motor (not shown) to make air flow forcedly. A rotating shaft 11a of the blower fan <NUM> may be disposed to be nearly horizontal to the ground. The blower fan <NUM> may be a crossflow fan.

The bottom panel <NUM> may include a grill <NUM> disposed to correspond to the inlet <NUM> in order to prevent foreign materials from entering the inside of the main body <NUM>, and a panel outlet <NUM> disposed to correspond to the outlet <NUM>. In the panel outlet <NUM>, a blade unit <NUM> may be rotatably disposed to open or close the panel outlet <NUM> or to adjust the up-down direction of discharged air. The panel outlet <NUM>, which is formed at the bottom panel <NUM>, may be connected to the outlet <NUM>. Accordingly, in the following description, the outlet <NUM> and the panel outlet <NUM> will be collectively called an outlet <NUM>.

The bottom panel <NUM> may include a filter member <NUM> configured to filter out foreign materials from air entered the inside of the main body <NUM> through the inlet <NUM>.

If the filter member <NUM> is used for long periods of time to collect many foreign materials therein, the filter member <NUM> may be cleaned or replaced with new one. In this case, in order to easily detach the filter member <NUM>, the grill <NUM> may be configured to be selectively opened with respect to the bottom panel <NUM>.

The grill <NUM> may rotate to be opened or closed in the state in which it is fixed and supported on the bottom panel <NUM> at its rear part.

The grill <NUM> may be disposed in front of the filter member <NUM> of the bottom panel <NUM>, and at least one part of the grill <NUM> may be cut to form a grill inlet <NUM>.

Hereinafter, the blade unit <NUM> according to an embodiment of the present invention will be described in detail.

<FIG> is an exploded perspective view showing the blade unit <NUM> according to an embodiment of the present invention, <FIG> is a cross-sectional view of the blade unit <NUM> cut along a line A-A of <FIG>, <FIG> is a side view showing a blade in which a coupling member of <FIG> is formed, <FIG> shows a buffer member in the blade unit <NUM> of <FIG>, <FIG> shows a side of the butter member of <FIG> in which a buffer groove is formed, <FIG> shows a connection member of the blade unit <NUM> of <FIG>, <FIG> is a front view showing a side of the connection member of <FIG> in which a connection groove is formed, <FIG> shows a third coupling member of the blade unit <NUM> of <FIG>, and <FIG> is an exploded perspective view showing a configuration of the third coupling member of <FIG>.

Referring to <FIG>, the blade unit <NUM> includes a blade <NUM>. The blade unit <NUM> is configured such that the blade <NUM> disposed in the outlet <NUM> rotates to adjust the direction of air heat-exchanged in and discharged from the inside of the main body <NUM>.

The blade <NUM> may be coupled with one edge of the bottom panel <NUM> so as to be rotatable in the outlet <NUM>, as shown in <FIG>. More specifically, the blade <NUM> may be hinge-coupled with one edge of the bottom panel <NUM> to be rotatable. The blade <NUM> may have a shape corresponding to the outlet <NUM> in order to open or close the outlet <NUM>. The blade <NUM> may be disposed in the inside of the outlet <NUM>, and configured to rotate on the axis of its one edge hinge-coupled with the bottom panel <NUM>.

According to an example, the blade <NUM> includes a body part <NUM>, and coupling members <NUM> or <NUM>.

The body part <NUM> may have a shape corresponding to the outlet <NUM>. The body part <NUM> may be in the shape of a rectangular plate. The section of the body part <NUM> may be smaller than the section of the outlet <NUM> so that the body part <NUM> can be positioned in the inside of the outlet <NUM>.

The coupling members <NUM> and <NUM> may be disposed on one edge of the body part <NUM>. The coupling members <NUM> and <NUM> couple the body part <NUM> with the main body <NUM> or the bottom panel <NUM> such that the body part <NUM> is rotatable.

The coupling members <NUM> and <NUM> may be provided as a plurality of coupling members. The plurality of coupling members <NUM> and <NUM> may be arranged in a straight line on one edge of the body part <NUM>. Accordingly, the blade <NUM> can rotate on the axis of the straight line formed by the plurality of coupling members <NUM> and <NUM>.

The plurality of coupling members <NUM> and <NUM> may be respectively disposed on both ends of the body part <NUM>. The plurality of coupling members <NUM> and <NUM> may include a first coupling member <NUM> and a second coupling member (not shown). The first coupling member <NUM> is, as shown in <FIG>, connected to a motor <NUM> which will be described later. The second coupling member may be positioned to face the first coupling member <NUM> on the blade <NUM>. The second coupling member may be connected to the main body <NUM> or the bottom panel <NUM> such that the blade <NUM> is rotatable.

As shown in <FIG>, the first coupling member <NUM> includes a coupling groove <NUM> and a fixing hole <NUM>.

The coupling groove <NUM> may be formed in one side of the first coupling member <NUM>. The coupling groove <NUM> is, as shown in <FIG>, formed in the side of the first coupling member <NUM> facing the motor <NUM> which will be described later. A buffer member <NUM> which will be described later is inserted into the coupling groove <NUM>. The coupling groove <NUM> may have a shape corresponding to the shape of the buffer member <NUM> which will be described.

The fixing hole <NUM> may be formed in a surface of the coupling groove <NUM> which is face the opening of the coupling groove <NUM>. A buffer protrusion <NUM> of the buffer member <NUM> which will be described later may be inserted into the fixing hole <NUM>. If the buffer protrusion <NUM> is inserted into the fixing hole <NUM>, the fixing hole <NUM> may fix the buffer member <NUM> at the first coupling member <NUM>. However, in other exemplary embodiments, the fixing hole <NUM> may be omitted.

The second coupling member may be positioned to face the first coupling member <NUM> on the blade <NUM>. The second coupling member may be hinge-coupled with the main body <NUM> or the bottom panel <NUM> so that the blade <NUM> can rotate.

As shown in <FIG>, the coupling members <NUM> and <NUM> may further include a third coupling member <NUM>. The third coupling member <NUM> may be positioned between the first coupling member <NUM> and the second coupling member. The third coupling member <NUM> may be positioned on the straight line formed by the first coupling member <NUM> and the second coupling member. The third coupling member <NUM> may be hinge-coupled with the main body <NUM> or the bottom panel <NUM> so that the blade <NUM> can rotate. Also, a plurality of third coupling members <NUM> may be arranged at regular intervals between the first coupling member <NUM> and the second coupling member.

As shown in <FIG> and <FIG>, the third coupling member <NUM> may include an external frame 119a, a buffer part 119b, and a protrusion 119c.

The external frame 119a may form the outer side portion of the third coupling member <NUM>. The buffer part 119b may be inserted into the inside of the external frame 119a. The buffer part 119b may be made of a material having a restoring force. Also, the butter part 119b may be made of a material having elasticity. One end of the protrusion 119c may be inserted into the buffer part 119b, and the other end of the protrusion 119c may extend from the buffer part 119b. The protrusion 119c may be coupled with the main body <NUM> or the bottom panel <NUM>. According to the above-described configuration, the third coupling member <NUM> may enable the blade <NUM> to rotate in the outlet <NUM> by changing the shape of the buffer part 119b.

The blade unit <NUM> further includes the motor <NUM>.

The motor <NUM> may be installed in the inside of the main body <NUM> and generates a rotatory force that is transferred to the blade <NUM>. The motor <NUM> includes a rotation transfer member <NUM>. The rotation transfer member <NUM> transfers a rotatory force generated by the motor <NUM> to the blade <NUM>. The configuration of the rotation transfer member <NUM> will be described later.

The blade unit <NUM> further includes the buffer member <NUM>.

The buffer member <NUM> is connected to the blade <NUM> and the rotation transfer member <NUM> of the motor <NUM>. The buffer member <NUM> is coupled with the blade <NUM> at one end, while surrounding a part of the rotation transfer member <NUM>. The buffer member <NUM> may be inserted into one end of the blade <NUM>, while surrounding a part of the rotation transfer member <NUM>. The buffer member <NUM> may transfer a rotatory force to the blade <NUM>, while rotating together with the rotation transfer member <NUM>.

The buffer member <NUM> is inserted into the coupling groove <NUM> of the first coupling part <NUM>. The buffer member <NUM> may have a shape corresponding to the coupling groove <NUM>. The buffer member <NUM> may be in the shape of a faceted pillar having at least one edge in the longitudinal direction. Accordingly, the buffer member <NUM> may rotate together with the first coupling member <NUM> in the state in which it is inserted into the coupling groove <NUM>.

According to the invention, the buffer member <NUM> includes a buffer body part <NUM>, and a buffer protrusion <NUM>, and may include a buffer groove <NUM>.

The buffer body part <NUM> may have a shape corresponding to the coupling groove <NUM>. As shown in <FIG>, the buffer body part <NUM> is inserted into and rested in the inside of the coupling groove <NUM> of the first coupling member <NUM>. The buffer body part <NUM> may include a stopping part 121a at one end. The stopping part 121a may extend from one end of the buffer body part <NUM>, and be caught by the first coupling member <NUM> when the buffer body part <NUM> is completely inserted into the coupling groove <NUM>. However, the stopping part 121a may be omitted.

The buffer protrusion <NUM> may be formed at one end of the buffer body part <NUM>. The buffer protrusion <NUM> is positioned to correspond to the fixing hole <NUM> when the buffer body part <NUM> is inserted into the coupling groove <NUM>. The buffer protrusion <NUM> may extend from the buffer body part <NUM>. The buffer protrusion <NUM> is inserted into the fixing hole <NUM> of the first coupling member <NUM>.

The buffer protrusion <NUM> may include a first protrusion 122b and a second protrusion 122a. The first protrusion 122b may extend from the buffer body part <NUM>. The first protrusion 122b may connect the buffer body part <NUM> to the second protrusion 122a. The first protrusion 122b may be inserted into the fixing hole <NUM>. The section of the first protrusion 122b may correspond to the inside section of the fixing hole <NUM>.

The second protrusion 122a may be positioned at one end of the first protrusion 122b. The second protrusion 122a may have a shape tapering from its part connected to the first protrusion 122b. The second protrusion 122a may be in the shape of a cone. The section of one end of the second protrusion 122a may be larger than that of the fixing groove <NUM>. One end of the second protrusion 122a may be caught by the outer edge of the fixing hole <NUM> when the buffer member <NUM> is completely inserted into the coupling groove <NUM>.

The buffer groove <NUM> may be formed in a portion of the buffer body part <NUM>. The buffer groove <NUM> may be formed in a portion of the buffer body part <NUM> that is opposite to the buffer protrusion <NUM>. The rotation transfer member <NUM> which will be described later may be inserted into the buffer groove <NUM>. The buffer groove <NUM> may have a shape corresponding to the rotation transfer member <NUM>.

The buffer groove <NUM> may be in the shape of a pillar having at least one edge in the longitudinal direction. The buffer groove <NUM> may be in the shape of a pillar whose section is in the shape of "+". The buffer groove <NUM> may be in the shape of a faceted pillar having at least one edge at the side. The buffer groove <NUM> may rotate together with the rotation transfer member <NUM> inserted therein to receive a rotatory force.

The buffer member <NUM> may be made of a material having a restoring force. Also, the buffer member <NUM> may be made of a material having elasticity. Accordingly, even when the rotation transfer member <NUM> and the blade <NUM> are not aligned on a straight line, the shape of the buffer member <NUM> may change so as to locate the blade <NUM> at a predetermined position. Also, the buffer member <NUM> may prevent vibrations and noise from being generated by vibrations of the motor <NUM> and rotation of the blade <NUM>. According to an example, the buffer member <NUM> may include rubber.

The rotation transfer member <NUM> is connected to the motor <NUM> to transfer a rotatory force generated by the motor <NUM> to the blade <NUM>. The rotation transfer member <NUM> may include a rotation shaft <NUM> and a connection member <NUM>.

The rotation shaft <NUM> may extend from one part of the motor <NUM>. The rotation shaft <NUM> may receive a rotatory force directly from the motor <NUM> and rotate.

The connection member <NUM> may be coupled with the rotation shaft <NUM> at one end, and coupled with the buffer member <NUM> at the other end. The connection member <NUM> may rotate together with the rotation shaft <NUM> to transfer a rotatory force to the buffer member <NUM> connected thereto.

As shown in <FIG>, the connection member <NUM> may include a connection body part 152a, a connection protrusion 152b, and a connection groove 152c.

The connection body part 152a may be coupled with the rotation shaft <NUM> at one end. In the one end of the connection body part 152a, a connection groove 152c may be formed. The rotation shaft <NUM> may be inserted into the connection groove 152c. The connection groove 152c may be configured such that the connection member <NUM> can rotate together with the rotation shaft <NUM> in the state in which the rotation shaft <NUM> is inserted into the connection groove 152c. The connection groove 152c may have a shape corresponding to the rotation shaft <NUM>.

The connection protrusion 152b may extend from the other end of the connection body part 152a. The connection protrusion 152b may be formed in a portion of the connection body part 152a that is opposite to the connection groove <NUM>.

The connection protrusion 152b may be coupled with the buffer member <NUM>. The connection protrusion 152b may be inserted into the buffer groove <NUM>. The connection protrusion 152b may have a shape corresponding to the buffer groove <NUM>. The connection protrusion 152b and the buffer groove <NUM> may be in the shape of a pillar whose section is in the shape of "+". The connection protrusion 152b and the buffer groove <NUM> may be in the shape of a faceted pillar having at least one edge at the side. The connection protrusion 152b may rotate together with the buffer member <NUM> in the state in which it is inserted into the buffer groove <NUM>.

The connection member <NUM> may be made of a material having stiffness that is lower than that of the rotation shaft <NUM> of the motor <NUM>. For example, the rotation shaft <NUM> of the motor <NUM> may be made of a metal material, and the connection member <NUM> may be made of a plastic material. Accordingly, the connection member <NUM> may prevent the buffer member <NUM> from being damaged upon rotation, compared to when the rotation shaft <NUM> made of a metal material is directly connected to the buffer member <NUM>.

In general, if the main body <NUM> is installed non-horizontally, the rotation transfer member <NUM> and the blade <NUM> may be not aligned on a straight line. In this case, the rotation axis of the blade <NUM> may change to disable the blade <NUM> to rotate, or the blade <NUM> may make vibrations and noise upon rotation.

However, in the blade unit <NUM> according to the above-described embodiment of the present invention, the buffer member <NUM> may be provided between the motor <NUM> and the blade <NUM>. The buffer member <NUM> may be made of a material having a restoring force to change its shape according to an external force. Accordingly, when the rotation transfer member <NUM> and the blade <NUM> are not aligned on a straight line, the shape of the buffer member <NUM> may change partially so as to locate the blade <NUM> at an appropriate position where it can rotate. Therefore, the blade <NUM> can be easily rotated, and also, vibrations and noise that can be generated due to rotation of the blade <NUM> can be prevented.

Hereinafter, a blade unit according to another embodiment of the present invention will be described.

<FIG> shows a blade unit according to another embodiment of the present invention, <FIG> is an exploded perspective view showing a configuration of the blade unit of <FIG>, and <FIG> is a cross-sectional view of the blade unit cut along a line B-B of <FIG>.

Referring to <FIG>, <FIG>, a blade unit <NUM> includes a blade <NUM>, a buffer member <NUM>, a motor <NUM>, a rotation transfer member <NUM>, and may include a guide hole <NUM> to guide the rotation transfer member <NUM>. Comparing to the blade unit <NUM> of <FIG>, the blade unit <NUM> may further include the guide hole <NUM> to guide the rotation transfer member <NUM>, and the remaining components of the blade unit <NUM> may be the same as those of the blade unit <NUM> of <FIG>. Hereinafter, descriptions about the same components of the blade unit <NUM> as those of the blade unit <NUM> of <FIG> will be omitted, and the blade unit <NUM> will be described based on differences from the blade unit <NUM> of <FIG>.

The guide hole <NUM> may be disposed in a partition wall <NUM> forming the outlet <NUM> in the inside of the bottom panel <NUM>. The guide hole <NUM> may be formed on a straight line on which a first coupling member <NUM> of the blade <NUM> and the rotation transfer member <NUM> are aligned. The guide hole <NUM> may function as a passage through which the motor <NUM> is connected to the blade <NUM>.

The guide hole <NUM> may guide the position of the rotation transfer member <NUM> connected to the motor <NUM> when the main body <NUM> or the bottom panel <NUM> is installed non-horizontally. The rotation transfer member <NUM> may be supported by the guide hole <NUM> when the main body <NUM> or the bottom panel <NUM> is maintained non-horizontally. Accordingly, the rotation transfer member <NUM> may be maintained at a predetermined position even when the main body <NUM> or the bottom panel <NUM> is installed non-horizontally. Also, since the rotation transfer member <NUM> is supported by the guide hole <NUM> when the main body <NUM> or the bottom panel <NUM> is installed non-horizontally, the guide hole <NUM> can reduce load transferred to the rotation transfer member <NUM>. Accordingly, it is possible to prevent the blade unit <NUM> from being damaged, while improving the reliability of the blade unit <NUM>.

Hereinafter, a modified example of the blade unit <NUM> will be described.

<FIG> shows a modified example of the blade unit <NUM> of <FIG>, and <FIG> is an exploded perspective view showing a blade unit of <FIG>.

Referring to <FIG>, a blade unit <NUM> may include the blade <NUM>, the buffer member <NUM>, the motor <NUM>, the rotation transfer member <NUM>, the guide hole <NUM>, and a gear unit <NUM>. Comparing to the blade unit <NUM> of <FIG>, the blade unit <NUM> may further include the gear unit <NUM>, and the remaining components of the blade unit <NUM> may be the same as those of the blade unit <NUM> of <FIG>. Hereinafter, the blade unit <NUM> will be described based on differences from the blade unit <NUM> of <FIG>.

The gear unit <NUM> may be configured to transfer greater torque to the blade <NUM> although the same motor <NUM> is used. According to an example, the gear unit <NUM> may include a first gear <NUM> and a second gear <NUM>. The first gear <NUM> may connect a rotation shaft 281a to the motor <NUM>. The second gear <NUM> may couple a rotation shaft 282a with the blade <NUM>. The second gear <NUM> may have a greater diameter than the first gear <NUM>.

The first gear <NUM> may be interlocked with the second gear <NUM>. According to the above-described configuration, the second gear <NUM> can transfer greater torque to the blade <NUM> than the first gear <NUM>. The gear unit <NUM> may generate great torque although the same motor is used, so as to reduce vibrations and noise that are generated upon use of the high capacity motor <NUM>.

Hereinafter, a blade unit according to another embodiment will be described.

<FIG> shows a blade unit according to another embodiment.

Referring to <FIG>, a blade unit <NUM> may include a blade <NUM>, a buffer member <NUM>, a motor <NUM>, and a rotation transfer member <NUM>. Comparing to the blade unit <NUM> of <FIG>, the rotation transfer member <NUM> of the blade unit <NUM> is different from the corresponding one of the blade unit <NUM> of <FIG>, and the remaining components of the blade unit <NUM> are the same as those of the blade unit <NUM> of <FIG>. Hereinafter, the blade unit <NUM> will be described based on differences from the blade unit <NUM> of <FIG>.

The rotation transfer member <NUM> may be provided as a rotation shaft extending from one end of the motor <NUM>. Unlike the blade unit <NUM> of <FIG>, in the blade unit <NUM>, the rotation shaft <NUM> may be directly coupled with the buffer member <NUM>. The rotation shaft <NUM> may be inserted into a buffer groove <NUM> formed in the buffer member <NUM>. Accordingly, the rotation shaft <NUM> may rotate due to a rotatory force transferred from the motor <NUM> in the state in which it is inserted into the buffer groove <NUM>, and transfer the rotatory force to the blade <NUM>.

Claim 1:
A blade unit for adjusting a direction of air that is heat-exchanged and discharged at an outlet (<NUM>, <NUM>) provided at an indoor unit (<NUM>) of an air conditioner, the blade unit (<NUM>, <NUM>) comprising:
a blade (<NUM>, <NUM>) rotatably couplable to the outlet of the indoor unit, and including a blade body (<NUM>, <NUM>) formed to extend with a long axis and a coupling member (<NUM>) arranged at an end portion of the blade body (<NUM>, <NUM>) in a direction of the long axis;
a motor (<NUM>, <NUM>) including a rotation transfer member (<NUM>, <NUM>), and configured to generate a force to be transferred to the blade (<NUM>, <NUM>); and
a buffer member (<NUM>, <NUM>) coupled to the blade (<NUM>, <NUM>), and formed to surround a portion of the rotation transfer member (<NUM>, <NUM>),
wherein the coupling member (<NUM>, <NUM>) includes a coupling groove (<NUM>) formed to be recessed towards an inner side with respect to the end portion of the blade body (<NUM>, <NUM>) in the direction of the long axis, and a fixing hole (<NUM>, <NUM>) formed through an inner side end of the coupling groove (<NUM>) in the direction of the long axis,
the buffer member (<NUM>, <NUM>) includes a body part (<NUM>) inserted into the coupling groove (<NUM>) and a protrusion (<NUM>, <NUM>) provided to be inserted into the fixing hole (<NUM>, <NUM>) while the body part (<NUM>) is inserted into the coupling groove (<NUM>), and
the protrusion (<NUM>, <NUM>) is inserted and coupled to the fixing hole (<NUM>, <NUM>) at the inner side with respect to the end portion of the blade body (<NUM>, <NUM>) in the direction of the long axis.