JPH10254431A - Fallboard opening and closing device for keyboard instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve operability and safety at the time of a fallboard closing operation by braking the abrupt rotation of a fallboard due to gravity. SOLUTION: A rotation type damping device 16 having a turning shaft 21 is provided at the inside face of an arm 4. The damping device 16 is a device using the viscous resistance of liquid and damping oil is sealed in the interior of the device. A damping lever 17 having an engagement part 33 consisting of a long groove is installed in the rotating shaft 21. A connecting lever 18 provided with a connecting pin 36 is provided in a fallboard 12 corresponding to it and the connecting pin 26 is made to be freely movably and attachably dettachably engaged with the engagement part 33. When the fallboard 12 is rotated from a lid closed state by roughly 90 deg. to become a vertical state, the connecting pin 36 is dettached from the engagement part 33. When the opening and closing operation of the fallboard 12 is performed, the turning shaft 21 is rotated by the engagement between the engagement part 33 and the connecting pin 36 to move the damping oil. Then, in a lid opening operation, the viscous resistance of the damping oil becomes small and in a lid closing operation, it becomes large to brake the fallboard 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard cover opening / closing device for a keyboard instrument, which improves safety in closing a keyboard cover.

[0002]

2. Description of the Related Art A general keyboard instrument such as a piano or an electronic piano has an openable / closable keyboard cover which covers an upper portion of a keyboard when not playing. The keyboard lid is long and heavy, and its rear end is pivotally attached to the instrument body via a hinge, so that the center of gravity moves forward from the middle of the opening / closing operation, especially during the closing operation. As a result, the weight suddenly drops as the weight increases. Therefore, a loud impact sound may be generated by hitting the mouth stick violently, or a finger may be accidentally pinched between the mouth stick and the keyboard cover.

In order to solve such inconveniences, various opening / closing devices are conventionally provided to prevent the fall of the keyboard cover. For example, Japanese Utility Model Laid-Open Publication No. 3-8391 discloses a keyboard cover opening / closing device applied to a keyboard cover of a grand piano. In this opening and closing device, a rotary oil damper utilizing viscous resistance of a fluid is buried in an inner surface of a brace, which is a constituent member of the musical instrument body, and a connecting tool is provided at a rotation center position on a side surface of the keyboard cover. The slit provided in the tool is engaged with the rotation shaft of the oil damper. According to such an opening and closing device, when the keyboard cover is opened, the viscous resistance of the fluid in the oil damper is small, and it can be easily and quickly opened with the same operating force as a keyboard cover without an opening and closing device. When it closes, the viscous resistance of the fluid gradually increases as it descends, braking the keyboard lid. Therefore, it can be slowly rotated and closed gradually.

[0004]

However, when the above-mentioned conventional opening / closing device is applied to an upright piano in which the keyboard is attached to the instrument body by hinges, the rotation of the oil damper and the keyboard lid is performed. If the centers do not match exactly, noise may occur, or parts may be worn or damaged, and there has been a problem that the assembly and adjustment work is troublesome.

Further, when applied to a keyboard lid having a large opening / closing angle, there is a problem in terms of operability. That is, the opening / closing angle of the keyboard lid varies depending on the type of the piano, the structure of the lid, and the like, but is usually about 90 ° for a grand piano and about 120 ° to 130 ° for an upright piano. When the above-described opening / closing device is applied to such a keyboard cover, when the opening / closing angle of the keyboard cover is about 90 °, even when the braking force is applied immediately when the cover is to be closed from the open state (substantially vertical state). No problem. Rather, since the center of gravity moves forward and the rotational force increases, it is preferable that the braking force acts. On the other hand, when the opening / closing angle is 120 ° to 130 °, the oil damper is controlled from the initial stage of the closing operation since the fully opened state tilts 30 ° to 40 ° further backward than the vertical state. When power is applied, it is necessary to overcome the braking force and the weight of the lid itself and move the lid to a substantially vertical position. For this reason, the operability at the initial stage of the closing operation is lower than that of a keyboard lid not provided with a shock absorber. Note that when the keyboard lid is rotated slightly forward from the vertical state, it subsequently rotates under its own weight, so that no operation force is required for closing the lid.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. It is an object of the present invention to make it easy to assemble and adjust and to reduce noise, wear and breakage of parts and the like. To provide a keyboard cover opening and closing device for a keyboard instrument. Another object of the present invention is to provide a keyboard cover opening / closing device for a keyboard instrument which does not act on the keyboard cover in the early stage of the closing operation and is suitable for a keyboard cover having an opening / closing angle of 90 ° or more. . A further object of the present invention is to provide a keyboard cover opening / closing device for a keyboard instrument in which a cover can be easily attached and detached similarly to a normal keyboard instrument without a shock absorber.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a keyboard cover opening / closing device for a keyboard instrument in which a keyboard cover is braked by viscous resistance of a fluid during closing operation. Provide a rotary shock absorber using
A brake lever having a long engaging portion extending in the longitudinal direction is provided on the rotation shaft of the shock absorber and extends along the inner surface of the musical instrument main body, and the brake lever is movably and detachably attached to the engaging portion. A connecting lever having an engaging pin to be engaged is provided on the keyboard cover. Further, the present invention is characterized in that the engagement pin of the connecting lever is disengaged from the engagement portion of the brake lever when the keyboard cover is changed from the closed state to a substantially vertical state.

The engaging pin of the connecting lever is engaged with the engaging portion of the braking lever when the keyboard cover is closed, and remains in the engaged state until the keyboard cover is turned to a substantially vertical state. The brake lever is rotated while being maintained, but when the brake lever is further rotated, the brake lever is released from the engagement portion. During the opening operation, the shock absorbing device has a low viscosity resistance of the fluid, and therefore can be opened with the same operation force as a normal keyboard lid. When the cover is opened at an angle larger than the vertical state (the engagement pin is disengaged from the engagement), the cover is gradually closed. Engage. Therefore, in the initial period until the engagement pin engages with the engagement portion, the shock absorber does not operate, and the rotation can be performed in the same manner as a normal keyboard lid. When the engagement pin engages with the engagement portion, the shock absorber operates thereafter to gradually increase the viscous resistance of the fluid to brake the keyboard cover. Therefore, the keyboard lid is not accelerated by its own weight and closes quietly. When the cover is opened to a substantially vertical position and the engaging pin is disengaged from the engaging portion, the connection with the shock absorber is released, so that the cover can be removed from the instrument body in the same manner as a normal cover. it can. The mounting position of the shock absorber may be a position displaced from the center of rotation of the keyboard cover, which facilitates mounting and adjusting work.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. 1 is an external perspective view of an upright piano provided with a keyboard cover opening / closing device according to the present invention, FIG. 2 is a side view of the keyboard cover when the cover is closed, and FIG. 3 is a state in which the keyboard cover is opened to a substantially vertical position. 4 is a side view of the keyboard cover when the cover is opened, FIG. 5A is a cross-sectional view when the shock absorber is closed, FIG. 5B is a cross-sectional view when the cover is being opened, and FIG. FIG. In these figures, an upright piano 1 includes a pair of left and right master plates 3, 3 forming a musical instrument main body 2, a pair of arms 4, 4 protruding from each of the master plates 3, 3, and these arms 4, 4. A shelf plate 5 laid in between, a mouth bar 6 provided at a front end of an upper surface of the shelf plate 5,
An upper front plate 7, a lower front plate 8, a top plate 9, a bottom plate (not shown), and the like are provided. A keyboard 10 having, for example, 88 keys, and a pair of right and left claps 11, 11 are arranged on the shelf 5. An openable / closable keyboard cover 12 that covers the keyboard is provided above the shelf board 5. As shown in FIG. 2, the rear end of the keyboard lid 12 is pivotally connected to the rear of the keyboard lid 14 in a vertical direction by a hinge 13 so that the opening / closing angle is, for example, about 120 °. As shown in FIG. 2, the lower surface of the front part is held in a substantially horizontal state by contacting the upper surface of the mouth bar 6. When the part is opened at the maximum angle, the front end surface comes into contact with and is supported by the upper front plate 7.

The inner surface of each arm 4 and the keyboard cover 12
A cover opening / closing device (hereinafter referred to as opening / closing device) 15 for braking the keyboard cover 12 at the time of closing the cover is provided. The opening / closing device 15 is a rotary type shock absorber 16 which is located behind the keyboard cover 12 and is embedded in the inner surface of the arm 4.
And a brake lever 17 and a connection lever 18 for transmitting the braking force of the shock absorber 16 to the keyboard lid 12.

The cushioning device 16 utilizes the viscous resistance of a fluid, and as shown in FIG. 5, a cylindrical case 20 and a rotating shaft 21 rotatably disposed in the cylindrical case 20.
And The interior of the cylindrical case 20 has two chambers,
That is, the first and second buffer chambers 23A and 23B are partitioned and incompressible damping oil 24 is sealed therein. The first and second buffer chambers 23A and 23B include a radial partition wall 25 provided on the inner peripheral surface of the cylindrical case 20 toward the center, and a partition wall 25 provided on the peripheral surface of the rotating shaft 21. It is formed by a V-shaped groove 26 to be inserted. Further, the first buffer chamber 23A and the second buffer chamber 23B
Communicate with each other through a communication hole 27 provided in the partition wall 25 to allow the damping oil 24 to flow. However, the damping oil 24 is moved from the first buffer chamber 23A to the second buffer chamber 2 by a check valve 28 provided in the communication hole 27.
Only the flow to 3B is allowed, and the flow from the second buffer chamber 23B to the first buffer chamber 23A is prevented. In addition,
When the keyboard cover 12 is completely closed, FIG.
The two side walls 26a, 26 forming the groove 26 as shown in FIG.
b, one side wall 26a is separated from the partition wall 25 by the maximum angle, the other side wall 26b is close to and opposes the partition wall 25, and most of the damping oil 24 is in the first buffer chamber 2
3A. For this reason, the second buffer chamber 23
The volume of B becomes almost zero. Conversely, when the keyboard cover 12 is open, the damping oil 24 moves into the second buffer chamber 23B as shown in FIG. 5C, and the volume of the first buffer chamber 23A becomes almost zero. Since the rotation angle of the brake lever 17 is approximately 120 to 130 °, the shaft of the damper, ie, the brake lever, cannot rotate unless the opening angle of the groove 26 is equal to or more than the same.

The rotating shaft 21 is inserted into the cylindrical case 20 while maintaining watertightness, and has an inner end having an outer diameter slightly smaller than the inner diameter of the cylindrical case 20. An arc-shaped protrusion 30 centered on the center O of the rotating shaft 21 is provided at the bottom of the groove 26.
Are formed integrally, and the protrusion 30 and the partition wall 2 are provided.
A throttle passage 31 is formed between the throttle passage 5 and the front end face of the throttle valve 5. One end of the rotating shaft 21 protrudes from the cylindrical case 20 to the outside, and one end of the braking lever 17 is fixed to the protruding end.

The brake lever 17 has a concave cross section and is formed long along the inner side surface of the arm 4 so that an engagement portion 33 having a long groove in the longitudinal direction is formed at the center of the surface.
Are formed. The engaging portion 33 is provided on the brake lever 17.
Are closed on the side of the rotation fulcrum and open on the free end side. The engaging portion 33 is not limited to a long groove, and may be a long hole.

The connecting lever 18 has a front end fixed to a rear end of a side surface of the keyboard lid 12 by a plurality of screws 35, a rear end extending rearward of the keyboard lid 12, and a rear end provided with the engaging portion. An engagement pin 36 movably and removably engaged with the projection 33 is integrally provided with the projection 33. The engagement pin 36
When the keyboard lid 12 is closed, as shown in FIG. 2, the rear end of the keyboard lid 12 is engaged with the engaging portion 33 and the brake lever 17 is held substantially horizontally. .
When the keyboard lid 12 is gradually opened from the closed state, the connecting lever 18 rotates integrally with the keyboard lid 12, so that the engaging pin 36 moves inside the engaging portion 33 and the braking lever 17 is moved. Rotate clockwise as shown in FIG. Then, when the keyboard lid 12 is rotated by approximately 90 ° to be in a vertical state, the engaging pin 36 is disengaged from the engaging portion 33. The braking lever 17
When the connecting lever 18 is made of metal or wood,
In order to smooth the movement of the engaging pin 36 and reduce the occurrence of sliding noise, the sliding surfaces of the engaging portion 33 and the engaging pin 36 are preferably coated with a synthetic resin. If the brake lever 17 is likely to rotate due to its own weight when the engagement pin 36 is disengaged from the engagement portion 33, an appropriate mechanism such as a spring 40 may be provided on the inner surface of the arm 4 as a position holding mechanism of the brake lever 17. A member may be provided.

Next, the switchgear 1 having such a structure will be described.
Operation 5 will be described. The keyboard lid 12 has an opening / closing angle of about 120 ° and is held in a substantially horizontal state when the lid is closed. At this time, the engagement pin 36 is located behind the rotation shaft 21 and is engaged with the engagement portion 33, and the brake lever 17 is held substantially horizontally (the state of FIG. 2). When the keyboard lid 12 is gradually opened from this state, the engagement pin 36
The brake lever 17 is pulled down while moving inside. Therefore, when the brake lever 17 rotates clockwise and the keyboard cover 12 rotates to a substantially vertical position, the engaging pin 36 is moved to the engaging portion 3.
Depart from 3. However, the keyboard cover 12 is further rotatable, and when held in contact with the upper front plate 7 as shown in FIG. In this state, the engagement pin 36 is located in front of the brake lever 17 as shown in FIG. The tip end of the brake lever 17 is held by a spring 40.

Here, when the keyboard lid 12 is closed, the shock absorber 16 is held in the state shown in FIG. In this state, when the brake lever 17 rotates in accordance with the opening operation of the keyboard lid 12, the rotation shaft 21 also rotates integrally. Therefore, the damping oil 24 in the first buffer chamber 23A mainly passes through the communication hole 27. And flows into the second buffer chamber 23B. Therefore, the viscous resistance of the oil at this time is small,
The braking force of the shock absorber 16 with respect to 2 is small. When the rotation shaft 21 rotates by a predetermined angle, most of the damping oil 24 in the first buffer chamber 23A is
Move into B. On the other hand, the keyboard lid 12 continues to rotate as described above, but the shock absorber 16 is disengaged from the engagement portion 33 and the rotation shaft 21 is
Since the rotation of a predetermined angle or more is restricted by the above, the state of FIG. 5C is maintained.

When the keyboard lid 12 is gradually closed from the maximum angle open state shown in FIG. 4, the connecting lever 18 rotates counterclockwise, and when the keyboard lever 12 becomes substantially vertical, the connecting lever 18 is engaged as shown in FIG. The pin 36 is engaged with the engaging portion 33 of the brake lever 17, and the brake lever 17 and the connection lever 18 are connected again. The brake lever 18 is rotated by the connection lever 18. Is released, and the holding of the spring 40 is released. Therefore, in the initial stage of the lid closing operation, that is, in the period until the engagement portion 33 and the engagement pin 36 are engaged, the shock absorber 15 does not act on the keyboard lid 12 at all, and the piano with no opening / closing device is not provided. It can be rotated with the same operation force as the keyboard cover.

When the keyboard cover 12 rotates to a substantially vertical state and the engagement pin 36 engages with the engagement portion 33, the shock absorber 16
Operates to brake the keyboard lid 12. That is, the engaging portion 33
The rotation shaft 21 is engaged with the engagement pin 36 as shown in FIG.
Is rotated counterclockwise from the state of FIG.
Most of the damping oil 24 in B is the throttle passage 31
And flows into the first buffer chamber 23A. The viscous resistance at this time is large because the sectional area of the throttle passage 31 is extremely small, and acts as a large braking force on the keyboard lid 12. In this case, since the distance L from the rotation shaft 21 to the engagement pin 36 is long when the engagement pin 36 is engaged with the engagement portion 33, the braking force of the shock absorber 16 is not so large. Thereafter, since the distance L gradually decreases, the braking force gradually increases, and the keyboard cover 12 is slowly rotated. Therefore, the keyboard lid 12 is not accelerated by its own weight, and does not emit a loud impact sound when it comes into contact with the closing stick 6 quietly.

In such an opening / closing device 15, since the shock absorber 16 can be mounted at a position displaced from the center of rotation of the keyboard lid 12, there is no need to make the centers of rotation of the two exactly coincide. , Installation and adjustment work is easy, and noise, wear and breakage of parts, etc. can be reduced. When the keyboard cover 12 is opened in a substantially vertical state, the engagement pins 36
Is detached from the engaging portion 33, so that when the screw fixing the hinge 13 is removed, the keyboard lid 12 can be easily removed from the musical instrument main body 2 as in a normal piano.

In the above embodiment, the damping oil 2 is used as the fluid used in the shock absorber 16.
Although the example using 4 has been described, the present invention is not limited to this, and air may be used when the keyboard lid 12 is light. In the above-described embodiment, the present invention is applied to the keyboard lid 12 of the upright piano 1. However, the present invention can also be applied to a keyboard instrument such as a grand piano or an electronic piano having an opening / closing angle of 90 ° or more. .

[0021]

As described above, the keyboard cover opening / closing device for a keyboard instrument according to the present invention is a keyboard cover opening / closing device for a keyboard instrument in which the keyboard cover is braked by viscous resistance of a fluid at the time of closing the cover. A rotary damping device utilizing the viscous resistance of the present invention, and a braking lever extending along the inner surface of the musical instrument main body and having a long engaging portion in the longitudinal direction is provided on a rotating shaft of the damping device. Since the connecting lever having an engaging pin movably and detachably engaged with the engaging portion is provided on the keyboard cover, it is not necessary to make the center of rotation of the shock absorbing device coincide with the rotation center of the keyboard cover. Can be easily attached and adjusted, and noise, wear and breakage of parts and the like can be reduced.

Further, when the cover is opened to a substantially vertical state, the engaging pin is disengaged from the engaging portion, and thereafter the shock absorber is completely inoperative. When the present invention is applied to a cover having an opening / closing angle of 90 ° or more, the cover is not braked in the initial stage of the closing operation, and can be rotated with the same operating force as a normal cover. Further, since the engaging pin is disengaged from the engaging portion, the attaching / detaching operation of the keyboard cover to / from the instrument main body is easy as in the case of a normal keyboard instrument.

[Brief description of the drawings]

FIG. 1 is an external perspective view of an upright piano including a keyboard cover opening / closing device according to the present invention.

FIG. 2 is a side view of the keyboard cover when the cover is closed.

FIG. 3 is a side view in a state where a keyboard cover is opened to a substantially vertical position.

FIG. 4 is a side view of the keyboard cover when the cover is opened.

FIG. 5A is a cross-sectional view of the shock absorber when the lid is closed,
(B) is a cross-sectional view in the middle of opening the lid, and (c) is a cross-sectional view in opening the lid.

[Explanation of symbols]

1 ... upright piano, 2 ... instrument body, 3 ... master board, 4
... arms, 5 ... shelf, 6 ... mouth stick, 10 ... keyboard, 12 ... key cover, 14 ... key cover back, 15 ... opening / closing device, 16 ... cushioning device, 17 ... braking lever, 18 ... connection lever, 21 ... Rotating shaft, 24 damping oil, 33 engaging part, 36 engaging pin.

Claims (2)

[Claims] 1. A keyboard cover opening / closing device for a keyboard instrument for braking a keyboard cover by viscous resistance of a fluid at the time of a closing operation, wherein a rotary shock absorber using a viscous resistance of a fluid is provided in the main body of the instrument, and the rotation of the shock absorber is controlled. A braking lever extending along the inner surface of the musical instrument main body and having a longitudinally long engaging portion provided on the moving shaft, and movably and detachably engaged with the engaging portion of the braking lever; A lid opening / closing device for a keyboard instrument, wherein a connecting lever having a pin is provided on the lid. 2. The lid opening / closing device for a keyboard instrument according to claim 1, wherein the engaging pin of the connecting lever is disengaged from the engaging portion of the brake lever when the lid is changed from the closed state to a substantially vertical state. Features a keyboard lid opening and closing device for keyboard instruments.