JP2010104420A - Chair for musical instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chair for a musical instrument on which a player can sit in a stable state while securing an excellent appearance upon performance, and which can be easily moved upon transportation. <P>SOLUTION: The chair 1 for the musical instrument for the player to sit thereon when playing the musical instrument includes: a seat part 2; a plurality of leg parts 3 extended downwards from the seat part 2; a plurality of caster housing parts 8 which are provided on the lower end parts of the plurality of leg parts 3, respectively, and whose lower surfaces are open; and a plurality of casters 4 which are provided on the lower end parts of the plurality of leg parts 3 respectively and are freely made to appear and disappear between a housed position to be housed in the caster housing parts 8 and a projecting position to project below the lower surface of the caster housing parts 8 with respect to the corresponding leg parts 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an instrument chair for a performer to sit when playing an instrument such as a piano.

  In general, a piano chair used when playing a piano includes a seat for a performer to sit on and four legs extending downward from four corners on the lower surface of the seat. Piano chairs are usually constructed so that the height of the seat, which is the upper surface of the seat, can be adjusted, and an adjustment mechanism for that purpose is built in. It has been. Such a piano chair is relatively heavy (for example, 10 to 20 kg) because the adjustment mechanism is incorporated and the piano chair is made heavy. Therefore, for example, moving the piano chair from the storage space to the front of the piano before performance, or returning the piano chair to the storage space after performance, etc., a relatively large effort is required when carrying the piano chair. Necessary. In particular, the burden of carrying a piano chair is large for a weak person such as a woman or a child.

  In order to reduce the labor for transporting the piano chair as described above, for example, it is conceivable to provide a caster at the lower end of the leg as in the piano chair disclosed in Patent Document 1. In this case, when the piano chair with casters is transported, the piano chair can be easily moved by pressing it from the side while it is placed on the floor.

  However, when performing while sitting on a piano chair with casters, the piano chair may move depending on the actions of the performer. In this case, the performer sitting on the piano chair plays with the lower body being unstable. Moreover, in the above-mentioned piano chair with casters, since the casters are exposed to the outside, the appearance and appearance of the piano chairs are worse than general ones without casters. Not suitable for use at concerts. The above-described problems occur in other musical instrument chairs used when playing musical instruments other than the piano.

  The present invention has been made in order to solve the above-described problems, and while performing, it is possible for the performer to sit in a stable state while securing a good appearance, and at the time of transportation. An object of the present invention is to provide a musical instrument chair that can be easily moved.

Japanese Patent Laying-Open No. 2005-40552

  In order to achieve the above object, the invention according to claim 1 is a musical instrument chair for a performer to sit at the time of playing a musical instrument, comprising: a seat portion; and a plurality of legs extending downward from the seat portion. A plurality of caster accommodating portions provided at the lower ends of the plurality of leg portions, respectively, and provided at the lower end portions of the plurality of leg portions, respectively, and each of the caster accommodating portions with respect to the corresponding leg portions. And a plurality of casters that can freely move in and out between a storage position to be stored and a protruding position that protrudes downward from the lower surface of the caster storage portion.

  According to this configuration, the plurality of caster accommodating portions are respectively provided at the lower ends of the plurality of leg portions extending downward from the seat portion, and the lower surfaces of the respective caster accommodating portions are open. In addition, a plurality of casters are provided at the lower ends of the plurality of legs, and each caster is accommodated with respect to the corresponding leg by an accommodation position accommodated in the caster accommodation part and a lower surface of the caster accommodation part. Also, it is configured to be able to appear and retract between the protruding position protruding downward. When playing on a musical instrument chair placed on the floor or the like, each caster is positioned in the accommodation position, so that the caster is not exposed to the outside by being covered with the caster accommodation portion. The lower surface of each leg, that is, the lower peripheral edge of each caster housing is in contact with the floor surface. Thereby, when performing, the performer can sit on the seat and sit on the instrument chair in a stable state while ensuring a good appearance of the instrument chair. On the other hand, when the musical instrument chair is transported before and after performance, the casters are brought into contact with the floor surface by positioning the casters at the protruding positions. As a result, when transporting the instrument chair, the instrument chair can be easily moved while using the casters by pushing it from the side, etc. Can do.

  According to a second aspect of the present invention, in the musical instrument chair according to the first aspect, the casters that are respectively provided inside the plurality of caster accommodating portions and that are accommodated in the corresponding caster accommodating portions are disposed on the protruding position side. A plurality of elastic members to be urged are further provided, and each of the plurality of elastic members is subjected to an external force of a predetermined magnitude or more on the seat portion from above when the instrument chair is placed on the floor surface. Sometimes, it allows the caster to move to the accommodation position due to the reaction force from the floor surface, and has an elastic force to hold the caster in the protruding position when external force from above is not acting on the seat part It is characterized by being.

  According to this structure, the some elastic member which urges | biases a caster to the protrusion position side is each provided inside the some caster accommodating part. Each elastic member has a predetermined elastic force. Specifically, when an external force of a predetermined magnitude or more acts on the seat portion from above in a state where the chair for a musical instrument is placed on the floor surface. In addition to allowing the caster to move to the accommodation position due to the reaction force from the floor surface, the caster has an elastic force to hold the caster in the protruding position when no external force is applied to the seat portion from above. As a result, for example, when the player sits on the seat and an external force greater than the predetermined magnitude acts on the seat from above, the casters are all moved toward the storage position by the reaction force from the floor. By being pressed, the caster is accommodated in the caster accommodating portion, and the lower peripheral edge portion of each caster accommodating portion comes into contact with the floor surface. As described above, the player can sit on the musical instrument chair while ensuring the function and effect of the performance in the above-described claim 1, that is, the good appearance of the musical instrument chair, by simply sitting on the seat. You can sit in the state. On the other hand, for example, when the performer is not sitting on the seat, when the external force from above is not acting on the seat, all of the casters are pushed downward from the caster housing by the elastic force of the elastic member. , Held in the protruding position. As a result, each caster is in contact with the floor surface, and the lower surface peripheral edge portion of the caster housing portion is lifted from the floor surface. Thereby, as above-mentioned, the chair for musical instruments can be moved easily, utilizing a caster.

  According to a third aspect of the present invention, in the musical instrument chair according to the second aspect, a plurality of casters are provided in the plurality of caster accommodating portions, and each of the plurality of casters accommodates in the corresponding caster accommodating portions. The first locking mechanism is further provided.

  According to this configuration, each of the plurality of caster accommodating portions is provided with the plurality of first lock mechanisms, and each first lock mechanism locks the caster accommodated in the corresponding caster accommodating portion to the protruding position. To do. Thereby, each caster is fixed in the up-down direction in a state of projecting downward with respect to the corresponding leg portion or caster housing portion. Therefore, when the musical instrument chair is transported, the musical instrument chair body can be stably moved without vibrating up and down during the movement.

  According to a fourth aspect of the present invention, in the musical instrument chair according to the third aspect, the plurality of casters are provided in the plurality of caster accommodating portions, and each of the plurality of casters accommodated in the corresponding caster accommodating portions is locked in the accommodating position. Each of the second lock mechanism and each of the plurality of caster accommodating portions, each configured to be operable from the outside, and a plurality of lock release portions for releasing the lock by the corresponding second lock mechanism, Is further provided.

  According to this configuration, each of the plurality of caster accommodating portions is provided with the plurality of second lock mechanisms, and each second lock mechanism locks the caster accommodated in the corresponding caster accommodating portion to the accommodated position. To do. Thereby, each caster is fixed in the state accommodated in the corresponding caster accommodating part. The instrument chair in this state is the same as that without a caster, and therefore can be handled in the same manner as an instrument chair without a caster. Further, each of the plurality of caster accommodating portions is provided with a plurality of lock release portions, and the lock of the casters by the corresponding second lock mechanism is released by operating each lock release portion. Since each lock release portion is configured to be operable from the outside, the caster can be easily unlocked by each second lock mechanism and can be protruded from the leg portion by an external operation.

  According to a fifth aspect of the present invention, there is provided the musical instrument chair according to any one of the first to fourth aspects, wherein the casters are respectively provided inside the plurality of caster accommodating portions, and each of the casters is accommodated in the corresponding caster accommodating portion. It is characterized by further comprising a plurality of vibration preventing portions that prevent the caster from vibrating by being in pressure contact with the caster when positioned at the storage position.

  According to this configuration, the plurality of vibration blocking portions for blocking the vibration of the casters are provided inside the plurality of caster housing portions. Each of the vibration preventing portions presses against the caster when the caster accommodated in the corresponding caster accommodating portion is located at the accommodating position, thereby preventing vibration of the caster. Thereby, at the time of performance, for example, even when the frequency of the musical sound generated by the performance matches the natural frequency of the caster, the resonance of the caster due to the musical sound can be prevented.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a piano chair to which a musical instrument chair according to a first embodiment of the present invention is applied. The piano chair 1 is for a performer to sit at the time of playing the piano, a seat 2 for the performer to sit on, four legs 3 extending downward from the lower surface of the seat 2, and these Each is provided at a lower end portion of the leg portion 3, and each includes four casters 4 that can be moved in and out of the corresponding leg portion 3.

  The seat portion 2 includes a box-shaped base 5 whose planar shape is a horizontally long rectangle, and a cushion 6 that is disposed on the upper side of the base 5 and has the same planar shape as the base 5. The base 5 incorporates an adjustment mechanism (not shown) for adjusting the height of the seat surface, which is the upper surface of the seat portion 2. This adjustment mechanism is a general mechanism composed of an X-link and the like, and two rotary handles 7 (only one is shown in FIG. 1) for operating the adjustment mechanism are provided on the left and right sides of the seat portion 2. Is provided. Therefore, the height of the seating surface of the seat portion 2 can be easily adjusted by turning both the handles 7 and raising and lowering the cushion 6.

  The four leg portions 3 are the same as each other, and extend downward from the four corners of the bottom surface of the base 5 by a predetermined length. At the lower end portion of each leg portion 3, a cylindrical caster accommodating portion 8 whose lower surface is opened is provided. The casters 4 corresponding to the respective leg portions 3 are entirely housed in the caster housing portion 8 (position shown in FIG. 1A), and the lower portion protrudes below the lower surface of the caster housing portion 8. It is possible to move in and out between the protruding position (the position shown in FIG. 1B). Since the four legs 3 including the casters 4 have the same configuration, the following description will be made on behalf of one leg 3.

  FIG. 2 is an enlarged view showing the internal structure of the lower end portion of the leg portion 3 with the caster 4 as the center, and shows a state where the caster 4 is located at the protruding position. As shown in the figure, the caster accommodating portion 8 provided at the lower end portion of the leg portion 3 has a predetermined height and thickness, and is formed in a cylindrical shape extending in the vertical direction.

  The caster 4 moves the wheel 11 through a wheel 11 having a predetermined diameter and thickness shorter than the horizontal minimum length in the caster accommodating portion 8 and a horizontal support shaft 12 penetrating the center of the wheel 11. It is comprised with the reverse U-shaped wheel holder 13 supported rotatably. The caster 4 is connected to the lower side of the slider 14 in the caster accommodating portion 8 via a connecting shaft 15.

  The slider 14 is formed in a block shape having a predetermined thickness and having a planar shape that is the same as the transverse section in the caster accommodating portion 8 and slightly smaller than the transverse section. The slider 14 is slidable in the vertical direction along the inner surface of the caster housing 8. The connection shaft 15 extends in the vertical direction, and an upper portion thereof is fixed to the center portion of the lower surface of the slider 14, while a lower portion thereof is rotatably connected to the wheel holder 13 of the caster 4. Thereby, the caster 4 is rotatable about the connecting shaft 15.

  Further, a caster spring 16 (elastic member) made of a coil spring is provided between the slider 14 and the ceiling surface 8a of the caster accommodating portion 8. The caster spring 16 urges the caster 4 toward the protruding position, and has the following elastic force. That is, the caster spring 16 has an elastic force that holds the caster 4 in the protruding position as shown in FIG. 2 when no external force is applied to the seat portion 2 of the piano chair 1. . Further, as shown in FIG. 3, the caster spring 16 is moved to the position where the caster 4 is accommodated by the reaction force R from the floor surface F when an external force A of a predetermined magnitude or larger acts on the seat portion 2 from above. It has an elastic force that allows movement.

  Further, a vibration preventing member 17 for preventing vibration of the caster 4 is attached to a predetermined position of the inner peripheral surface 8b of the caster accommodating portion 8. The vibration preventing member 17 is composed of a skin, felt, or the like having a predetermined thickness, and is bonded over the entire circumference of the inner peripheral surface 8 b of the caster housing portion 8. And this vibration prevention member 17 press-contacts to the wheel 11, when the caster 4 is located in an accommodation position, as shown in FIG.3 (b).

  As described above, according to the piano chair 1 of the present embodiment, for example, when the performer sits on the seat 2, the external force A acting on each leg 3 from above is greater than or equal to the predetermined magnitude. In some cases, as shown in FIGS. 1 and 3, the casters 4 are both accommodated in the caster accommodating portion 8 by being pressed toward the accommodating position by the reaction force R from the floor surface F. As a result, the casters 4 are not exposed to the outside by being covered with the caster accommodating portions 8, and the lower peripheral edge portions of the caster accommodating portions 8 of the leg portions 3 abut against the floor surface F. In this way, the player can sit on the piano chair 1 in a stable state while ensuring a good appearance of the piano chair 1 simply by sitting on the seat 2. In this case, the vibration preventing member 17 in each caster accommodating portion 8 is in pressure contact with the wheel 11 of the caster 4. Thereby, even when the frequency of the musical sound generated by the performance when the piano is played matches the natural frequency of the caster 4 (wheel 11 or the like), resonance of the caster 4 due to the musical sound can be prevented.

  On the other hand, for example, when the player is not sitting on the seat 2, when the external force from above is not acting on the seat 2, all of the casters 4 are caster accommodating portions 8 by the elastic force of the caster springs 16. Is pushed downward and held in the protruding position. As a result, each caster 4 is in contact with the floor surface F, and the lower surface peripheral portion of the caster accommodating portion 8 is in a state of floating from the floor surface F. As a result, when the piano chair 1 is transported, the piano chair 1 can be easily moved while using the caster 4 by pushing it from the side while being placed on the floor F without lifting it. Can be made.

  Next, a second embodiment of the present invention will be described with reference to FIG. In the piano chair of the present embodiment, each caster 4 can be moved in and out of the corresponding leg 3 between the protruding position and the storage position, and can be locked to the protruding position, as in the first embodiment described above. Has been. In the following description, the same components as those of the piano chair 1 of the first embodiment described above are denoted by the same reference numerals, detailed description thereof will be omitted, and differences from the first embodiment will be mainly described. Shall.

  As shown in FIG. 4A, the piano chair 1 of the present embodiment is provided on each of the four legs 3, and has four lock mechanisms 21 (first lock mechanisms) that lock the corresponding casters 4 in the protruding positions. It has. Each lock mechanism 21 is provided on the slider 14, and includes a lock member 22 that can be protruded and retracted horizontally with respect to the side surface of the lock mechanism 21 and a coil spring, and is a lock that urges the lock member 22 in a direction protruding outward from the slider 14. A spring 23 is used. The slider 14 is provided with a lock member receiving recess 14a that opens laterally and has a predetermined depth, and the lock member 22 is housed in the lock member receiving recess 14a so as to be able to appear and retract.

  As shown in FIG. 4C, the lock member 22 extends along the lock member housing recess 14a, and is formed so that the tip end portion (the right end portion in FIG. 4) is curved outwardly. Moreover, the lock spring 23 is built in the lock member accommodation recessed part 14a, and as mentioned above, always urges the lock member 22 in the protruding direction.

  On the other hand, at a predetermined position on the inner side surface 8 b of the caster housing portion 8, a lock recess 24 is provided in which the lock member 22 of the lock mechanism 21 can be engaged. The lock recess 24 opens inward and has a shape complementary to the tip of the lock member 22.

  In addition, although illustration is abbreviate | omitted, the vibration prevention member 17 similar to 1st Embodiment is attached to each leg part 3 of the piano chair 1 in the predetermined position of the inner surface 8b of the caster accommodating part 8. FIG.

  In the lock mechanism 21 and the lock recess 24 configured as described above, the tip end portion of the lock member 22 engages with the lock recess 24 as shown in FIGS. As a result, the slider 14 is locked in the up-down direction relative to the caster accommodating portion 8 of the leg portion 3. As a result, the caster 4 is locked at the protruding position.

  On the other hand, in a state where the caster 4 is locked at the protruding position, by applying an external force of a predetermined magnitude or more to the seat 2 from above, such as a player sitting on the seat 2, the component force of the external force is It acts on the lock member 22 from the lock recess 24 side. Thus, the lock member 22 is pressed inward of the lock member housing recess 14 a against the urging force of the lock spring 23, and the engagement with the lock recess 24 is released. As a result, the caster 4 is unlocked at the protruding position, and is allowed to move to the accommodation position as shown in FIG.

  Each leg 3 is provided with a stopper 25 protruding at a predetermined position on the inner surface 8 b of the caster housing 8. The stopper 25 is configured such that the slider 14 abuts from above when the caster 4 is located at the protruding position. Therefore, when the caster 4 located at the housing position is moved to the projecting position, for example, by lifting the leg 3 from the floor surface F, the caster 4 is vigorously moved by the urging force of the caster spring 16 and moved to the projecting position side. Even when the slider 14 moves, the slider 14 is stopped by the stopper 25, whereby the height of the lock member 22 of the lock mechanism 21 matches that of the lock recess 24, and the lock member 22 fits into the lock recess 24. As a result, the caster 4 is reliably locked at the protruding position by the lock mechanism 21.

  As described above, according to the present embodiment, it is possible to obtain the same effects as those of the first embodiment described above, and in addition, the casters 4 can be locked in the protruding position. Since the caster 4 can be locked in the protruding position as described above, when the piano chair 1 is transported, the movement of the piano chair 1 can be stably performed without vibrating up and down during the movement.

  Next, a third embodiment of the present invention will be described with reference to FIGS. In the piano chair of the present embodiment, each caster 4 can move freely between the protruding position and the storage position with respect to the corresponding leg 3 as in the first embodiment, and is the same as in the second embodiment. Each caster 4 can be locked in the protruding position, and in addition, it can be locked in the accommodation position. In addition, in the following description, the same code | symbol is attached | subjected about the same component as the piano chair 1 of 1st and 2nd embodiment mentioned above, the detailed description is abbreviate | omitted, and it is with 1st and 2nd embodiment. The difference will be mainly explained.

  As shown in FIGS. 5 and 6, the piano chair 1 of the present embodiment is provided on each of the four legs 3, and has four lock mechanisms 31 that lock the corresponding casters 4 to one of the protruding position and the storage position. (First and second lock mechanisms) and four lock release switches 32 (lock release portions) for releasing the lock of the caster 4 at the storage position. Each lock mechanism 31 includes a lock member 22 and a lock spring 23 as in the lock mechanism 21 of the second embodiment. Further, the caster accommodating portion 8 is provided with the lock recess 24 of the second embodiment, and at a predetermined position above it, a lock hole 33 that can be engaged with the lock member 22 of the lock mechanism 31 is provided.

  As shown in FIG. 6, the lock release switch 32 is provided outside the caster accommodating portion 8 so as to extend in the vertical direction. The switch main body 34 swings around a fulcrum 34a at the center thereof, and the switch main body. It comprises a switch spring 35 and the like that urges 34 to the lock position side described later. An unlocking projection 34 b that protrudes into the lock hole 33 of the caster accommodating portion 8 is provided on the upper back surface of the switch body 34. Then, the switch body 34 has a lock release position (see FIGS. 7B and 7C) where the unlocking projection 34b reaches the inner side surface 8b of the caster accommodating portion 8 with the fulcrum 34a as the center, and the unlocking projection. The part 34b is configured to be swingable between a lock position (see FIGS. 6, 7A and 7D) where the part 34b is separated from the inner surface 8b.

  In the lock mechanism 31 and the lock hole 33 configured as described above, as shown in FIG. 6, the tip of the lock member 22 is engaged with the lock hole 33 so that the caster of the leg 3 is engaged. The slider 14 is locked in the up-down direction with respect to the accommodating portion 8. Thereby, the caster 4 is locked in the accommodation position.

  Here, with reference to FIG. 7, the unlocking procedure of the caster 4 locked in the accommodation position will be briefly described. FIG. 2A shows a state in which the caster 4 is locked in the accommodation position and the piano chair 1 is placed on the floor surface F. From this state, first, one or two legs 3 are lifted by hand and floated from the floor F as shown in FIG. 5B, and the switch body 34 of the unlocking switch 32 is moved in the direction of the white arrow. Push. Thereby, when the lock member 22 of the lock mechanism 31 is removed from the lock hole 33, the lock of the caster 4 at the accommodation position is released. The caster 4 moves to the protruding position side together with the slider 14 by the restoring force of the caster spring 16.

  As shown in FIG. 7C, when the caster 4 reaches the protruding position by the slider 14 coming into contact with the stopper 25, the lock member 22 of the lock mechanism 31 is fitted in the lock recess 24 of the caster housing portion 8. To do. As a result, the caster 4 is locked at the protruding position. Then, by releasing the hand from the leg 3 from which the caster 4 is projected, the caster 4 is placed on the floor surface F as shown in FIG. Thereafter, the casters 4 of the other leg portions 3 that are locked in the accommodation position are similarly unlocked.

  As described above, according to this embodiment, it is possible to obtain the same operational effects as those of the first and second embodiments described above, and in addition, the casters 4 can be locked in the storage position. Thus, in a state where the caster 4 is locked in the accommodation position, the piano chair 1 is the same as the one without the caster 4, and therefore can be handled in the same manner as the piano chair without the caster. In addition, since the lock release switch 32 is provided outside the caster accommodating portion 8 of each leg portion 3, the caster 4 locked in the accommodating position by the lock mechanism 31 can be easily locked by operating this switch. The casters 4 can be protruded from the legs 3.

  In addition, this invention can be implemented in various aspects, without being limited to each described embodiment. In any of the embodiments, the case where the musical instrument chair of the present invention is applied to a piano chair has been described. However, the present invention is not limited to this, and can be applied to a musical instrument chair that plays a musical instrument other than a piano. Of course.

  In addition, the detailed configuration of the piano chair 1, the caster 4, and the lock mechanisms 21 and 31 shown in the embodiment are merely examples, and can be appropriately changed within the scope of the gist of the present invention. For example, in the embodiment, coil springs are employed as the caster spring 16, the lock spring 23, and the switch spring 35. However, other types of elastic members such as leaf springs may be used as long as they have similar functions. A spring or rubber having a predetermined elastic force may be employed.

It is a perspective view which shows the piano chair to which the chair for musical instruments by 1st Embodiment of this invention is applied, (a) is the state in which the caster was accommodated in the leg part, (b) is the caster protruded from the leg part. Indicates the state. It is a figure which expands and shows the caster which protruded from the leg part, and its circumference | surroundings, (a) is a state when it sees from the direction orthogonal to the support shaft of a caster, (b) is from the length direction of a support shaft. Shows the state when viewed. (A) And (b) is respectively the figure corresponding to (a) and (b) of FIG. 2, and is a figure which expands and shows the caster accommodated in the leg part and its periphery. It is a figure which expands and shows the inside of the lower end part of the leg part of the piano chair to which the chair for musical instruments by 2nd Embodiment of this invention is applied, (a) is the state by which the caster was locked to the protrusion position, (b) ) Is a state where the caster is located at the accommodation position, and (c) is an enlarged view of the inside of the one-dot chain line circle of (a). It is a perspective view which shows the piano chair which applied the chair for musical instruments by 3rd Embodiment of this invention, (a) is the state in which the caster was accommodated in the leg part, (b) is the caster protruded from the leg part. Indicates the state. It is a figure which expands and shows the inside of the lower end part of the leg part of the piano chair of Fig.5 (a), and shows the state by which the caster was locked to the accommodation position. It is explanatory drawing which shows operation at the time of making the caster of the piano chair of FIG. 5 protrude from a leg part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piano chair 2 Seat part 3 Leg part 4 Caster 8 Caster accommodating part 16 Caster spring (elastic member)
17 Vibration prevention member 21 Lock mechanism (first lock mechanism)
31 Locking mechanism (first and second locking mechanisms)
32 Unlocking switch (unlocking part)
F Floor A External force R Reaction force

Claims (5)

An instrument chair for a performer to sit when playing an instrument,
A seat,
A plurality of legs extending downward from the seat;
A plurality of caster accommodating portions each provided at a lower end portion of the plurality of leg portions and having a lower surface opened;
Each of the plurality of leg portions is provided at the lower end portion, and each of the corresponding leg portions is accommodated in the caster accommodating portion, and the protruding position is projected below the lower surface of the caster accommodating portion. With multiple casters that can move in and out,
A musical instrument chair characterized by comprising: A plurality of elastic members which are respectively provided inside the plurality of caster accommodating portions, and each urge the casters accommodated in the corresponding caster accommodating portions toward the protruding position,
Each of the plurality of elastic members is caused by a reaction force from the floor surface when an external force of a predetermined magnitude or more acts on the seat portion from above in a state where the instrument chair is placed on the floor surface. The caster is allowed to move to the accommodation position, and has an elastic force to hold the caster at the protruding position when no external force is applied to the seat portion. The musical instrument chair according to claim 1.   Each of the plurality of caster accommodating portions is further provided with a plurality of first lock mechanisms that lock the casters accommodated in the corresponding caster accommodating portions to the protruding positions, respectively. The musical instrument chair according to claim 2. A plurality of second lock mechanisms each provided in the plurality of caster accommodating portions, each locking the casters accommodated in the corresponding caster accommodating portions, to the accommodation position;
Each of the plurality of caster housing portions is configured to be operable from the outside, and a plurality of lock release portions for releasing the lock by the corresponding second lock mechanism;
The musical instrument chair according to claim 3, further comprising:   Each of the plurality of caster accommodating portions is provided inside, and each of the casters accommodated in the corresponding caster accommodating portion is in pressure contact with the caster when the caster accommodated in the corresponding caster accommodating portion is located at the accommodating position. The instrument chair according to any one of claims 1 to 4, further comprising a plurality of vibration blocking portions for blocking the vibration.

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