A piano adjustment gauge and its measurement and adjustment method

Abstract

The present invention provides a piano adjustment gauge and a measurement and adjustment method thereof, wherein the piano adjustment gauge comprises a first gauge, a second gauge and a third gauge; the three gauges of the present invention can be used individually or in combination for adjustment and comparison, and provide a basis for the tuning and adjustment of all parameters in the piano mechanical adjustment process. After testing, this set of gauges covers all parameters of all keyboard mechanical adjustments such as piano striking distance, keyboard height, sinking depth, disconnection distance, hammer return, hammer fall, and muffler start time, greatly improving the speed and efficiency of piano tuning. In terms of accuracy, through the combined use of several gauges, the accuracy of each adjustment parameter is higher and the error is smaller. The design of this set of gauges enables piano tuners to complete piano tuning and adjustment work more scientifically, accurately, efficiently and comprehensively, which is a first in domestic piano tuning tools.

Description

Technical Field

[0001] The present invention relates to the technical field of piano adjustment, and in particular to a piano adjustment gauge and a measuring and adjusting method thereof; in particular, to a piano adjustment gauge applicable to blind tuners and a measuring and adjusting method thereof. Background Art

[0002] At present, a piano has more than 8,000 parts, most of which are made of wood. Changes in temperature and humidity will cause deformation of the wood. To ensure the best pitch and touch of the piano, the piano is tuned and the mechanical touch is adjusted twice a year. Currently, piano adjustments mainly rely on the experience of piano tuners. The results of adjustments often vary depending on the level and subjectivity of the tuner, and the precision and accuracy cannot be guaranteed. Summary of the invention

[0003] The object of the present invention is to provide a piano adjustment gauge and a measurement and adjustment method thereof to solve at least one of the above-mentioned technical problems existing in the prior art.

[0004] In order to solve the above technical problems, the present invention provides a piano adjustment measuring tool, comprising: a first measuring tool;

[0005] The first measuring tool is in the shape of a trapezoidal block as a whole;

[0006] The shape of the first measuring tool in a first cross section parallel to the xy projection plane is a rectangle;

[0007] The shape of the first measuring tool on the second cross section parallel to the yz projection plane is a right-angled trapezoid; the plane on the first measuring tool that is parallel to the xz projection plane and contains the right-angled waistline of the right-angled trapezoid is the right-angled detection surface; the surface that faces the right-angled detection surface and contains the oblique waistline of the right-angled trapezoid is the oblique detection surface;

[0008] The first measuring tool comprises a front end detection surface and a rear end detection surface respectively arranged parallel to each other at both ends in the z-axis direction;

[0009] The front end detection surface is a rectangle with a width of 18mm-22mm and a height of 9.5mm-11.5mm.

[0010] Among them, the front end detection surface is 9.5mm-11.5mm high and can be used to measure or mark the front end sinking depth of the adjusted key.

[0011] Furthermore, the gradient (or slope) of the inclined detection surface is 23:22.

[0012] Furthermore, the front end detection surface is a rectangle with a width of 20 mm and a height of 10.5 mm.

[0013] Furthermore, the rear end detection surface is a rectangle with a width of 18mm-22mm and a height of 7.3mm-9.3mm. The widths of the front end detection surface and the rear end detection surface are the same.

[0014] The height of the rear detection surface is 7.3mm-9.3mm, which can be used to measure or mark the middle sinking depth of the adjusted key.

[0015] Furthermore, the rear end detection surface is a rectangle with a width of 20 mm and a height of 8.3 mm.

[0016] For ease of expression, this application uses a three-dimensional coordinate system to define directions, where the Z-axis direction is parallel to each piano key, the y-axis direction is the up and down height direction, the x-axis direction is the left and right direction, the side of the piano or measuring tool close to the person is the front side or front end, and the side away from the person is the back side or rear end.

[0017] Furthermore, the length of the first measuring tool is 45-50 mm, that is, the height of the right-angled trapezoid is 45-50 mm.

[0018] Furthermore, the length of the first measuring tool is 46 mm or 48 mm, that is, the height of the right-angled trapezoid is 46 mm or 48 mm.

[0019] Furthermore, the first measuring tool is made of mahogany, organic material or metal material, so that piano tuners can choose to use it in different climates, different temperatures or different humidity conditions.

[0020] In addition, the piano adjustment gauge also includes: a second gauge;

[0021] The second measuring tool is in the shape of a rectangular block as a whole, and includes: an upper measuring surface and a lower measuring surface; the upper measuring surface and the lower measuring surface are parallel to each other, and the distance between them is 15mm; a sinking platform is provided at one end of the upper measuring surface, and the sinking platform includes a sinking platform detection surface parallel to the lower measuring surface, and the distance between the sinking platform detection surface and the lower measuring surface is 13mm. That is, the height of the sinking platform is 2mm.

[0022] The 2mm recessed design can better fit the white keys of the grand piano to measure the height and key level of the grand piano keyboard. Generally, when the lower lock of the grand piano is removed, there will be a height difference between the front end of the keyboard and the front edge of the shelf where the measuring tool is placed. The 2mm recessed design perfectly solves this problem.

[0023] Furthermore, the second measuring tool has a length of 65 mm and an overall width of 64 mm, that is, the lower measuring surface is a rectangular surface with a length of 65 mm and a width of 64 mm.

[0024] Furthermore, the length of the sinking platform or the sinking platform detection surface is 65 mm and the width is 12 mm; the length of the upper measuring surface is 65 mm and the width is 52 mm.

[0025] Furthermore, the second measuring tool is made of mahogany, organic material or metal material, so that piano tuners can choose to use it in different climates, different temperatures or different humidity conditions.

[0026] And, the piano adjustment gauge further includes: a third gauge;

[0027] The third measuring tool includes a special-shaped portion; the cross-section of the special-shaped portion is V-shaped, including a first measuring plate and a second measuring plate arranged at an angle, the thickness of the first measuring plate is 1.5 mm; the thickness of the second measuring plate is 2 mm.

[0028] Furthermore, the angle between the first measurement plate and the second measurement plate is 90°.

[0029] Furthermore, the third measuring tool also includes a rectangular parallelepiped portion; the cross-section of the rectangular parallelepiped portion is a square with a height of 12 mm and a width of 12 mm.

[0030] Furthermore, the third measuring tool is in the shape of a cylinder as a whole, and the cross-section of the cylinder is square; a groove with a rectangular cross-section is provided at one end of the cylinder; the corresponding part of the groove on the cylinder is the special-shaped part (the two plate-shaped bodies surrounding the groove are the first measuring plate and the second measuring plate, respectively), and the non-groove part on the cylinder is the rectangular parallelepiped part.

[0031] Furthermore, the overall length of the third measuring tool is 48 mm, the length of the rectangular parallelepiped portion is 24 mm; the length of the groove and the special-shaped portion is 24 mm.

[0032] Furthermore, a scale line is arranged on the outer side surface of the cuboid portion for marking the distance from an end surface of one side of the cuboid.

[0033] Furthermore, the scale lines include at least 18 mm, 20 mm and / or 22 mm scale lines.

[0034] In addition, the present invention also discloses a piano measurement and adjustment method using the piano adjustment gauge, which specifically comprises the following steps:

[0035] Step S10, measuring the sinking depth of the front end of the white key

[0036] The inclined detection surface of the first measuring tool is placed downward against the white key to be tested, and the right-angle detection surface is upward, so that the front detection surface of the first measuring tool is flush with the front vertical surface (outer end surface) of the white key to be tested; the white key to be tested is pressed with force (the force is the medium force that a pianist usually uses when playing), and the white key to be tested moves in an arc with the middle pin as a fulcrum, and the sinking depth of the front end of the white key to be tested is determined by comparing the height difference between the right-angle detection surface and the keys on the two adjacent sides of the white key to be tested;

[0037] When the right-angle detection surface is higher than a certain measurement value (visual measurement value or tool measurement value) on the adjacent two sides of the keys, the sinking depth of the front end of the detected white key is the difference between the height of the front detection surface and the measurement value;

[0038] When the right-angle detection surface is lower than a certain measurement value (visual measurement value, touch measurement value or tool measurement value) on the adjacent two sides of the keys, the front end sinking depth of the detected white key is the sum of the height of the front end detection surface and the measurement value;

[0039] Step S11, adjustment of the sinking depth of the front end of the white key

[0040] If the front end of the white key sinks too deep or too shallow, it can be adjusted by adding or removing the large paper ring on the front pin. Adjusting the sinking depth of the white key by adding or removing the large paper ring on the front pin is a common method used by existing tuners and will not be described in detail here.

[0041] When adding or removing paper rings, try to use thick paper rings instead of multiple thin paper rings, and follow the principle of thick paper rings at the bottom and thin paper rings at the top.

[0042] For example, the front end sinking depth of the pre-adjusted white key is 10.5mm, and the height of the front end detection surface is 10.5mm. When adding or removing paper circles, when the pre-adjusted white key is pressed down with medium force (or pressed down with a 200g weight), the right-angle detection surface is flush with the top of the adjacent keys on both sides.

[0043] After a certain amount of training, a piano tuner (including a blind piano tuner) can adjust the sinking depth to any value between 9.5 mm and 11.5 mm by using the first measuring tool, with an error of less than 0.1 mm.

[0044] Furthermore, the method further comprises step S12:

[0045] Place the inclined detection surface of the first measuring tool downward against the white key to be inspected, with the right-angle detection surface facing upward, and the front detection surface of the first measuring tool flush with the front elevation (outer end surface) of the white key to be inspected; the upper edge of the front detection surface (the corner edge between the front detection surface and the right-angle detection surface) is flush with the keys on the two adjacent sides of the white key to be inspected, and when there is a height difference between the upper edge of the rear detection surface (the corner edge between the rear detection surface and the right-angle detection surface) and the keys on the two adjacent sides of the white key to be inspected, it indicates that the key has wood deformation. For example, a blind tuner can judge whether the key has wood deformation by touching the height difference between the front and rear ends of the right-angle detection surface and the keys on the two adjacent sides.

[0046] Furthermore, the method further comprises step S13:

[0047] When the wood of the piano key is deformed, the height difference between the upper edge of the rear end detection surface (the corner edge between the rear end detection surface and the right-angle detection surface) and the upper surface of the keys on both sides of the white key being detected is used to determine the sinking depth of the white key being detected.

[0048] The specific measurement and adjustment method is the same as the measurement and adjustment of the front end sinking depth.

[0049] Furthermore, the method further comprises step S14, measuring the height of the upright piano keyboard;

[0050] The right-angle detection surface is placed horizontally against the front face of the key, and the key height can be determined by touch comparison. Specifically, when the first gauge is 20 mm thick, that is, the front and rear detection surfaces are 20 mm wide, the key height can be determined by comparing the thickness of the key with the first gauge. Experiments have shown that after practice, blind tuners can use the first gauge to determine and adjust any key height between 18 mm and 22 mm, laying a good foundation for a good residual touch.

[0051] Furthermore, the method further comprises step S15, measuring the striking distance of the string;

[0052] The front detection surface of the first gauge is placed against the strings, and the distance between the rear detection surface and the striking point of the tip of the hammer is measured (touch), thereby measuring the striking distance of each hammer. That is, the length of the first gauge is used as a scale, and the striking distance of each hammer can be measured and determined by comparison; and the striking distance is the basis of all mechanical adjustments.

[0053] In addition, a piano measurement and adjustment method using the piano adjustment gauge further includes step S20:

[0054] Measuring the return distance of the piano using the second measuring tool;

[0055] Specifically, the lower measuring surface is placed against the strings, and the keys are played. The distance between the hammer corresponding to the played keys and the upper measuring surface or the sinking platform detection surface when in the receiving state is measured, and the measured distance is the return distance.

[0056] Furthermore, when measuring the return distance of the grand piano, the upper measuring surface is facing the hammer, and the distance between the hammer and the upper measuring surface when the hammer is in the supported state is measured (visually or by touch).

[0057] Furthermore, when measuring the return distance of the upright piano, the sinker detection surface faces the hammer, and the distance between the hammer and the sinker detection surface when the hammer is in the supported state is measured (visually or by touch).

[0058] Furthermore, the method further comprises step S21, measuring the height of the keyboard;

[0059] The lower measuring surface is placed against the front vertical surface (outer end surface) of the key, and the lower side surface of the second measuring tool is placed against the table of the mechanical adjustment frame, and the distance between the upper side surface of the second measuring tool and the key surface is measured by comparison.

[0060] Among them, the grand piano has higher requirements and is difficult to adjust. The lower measuring surface is a 64mm*65mm rectangle, which can detect 64mm and 65mm keyboard heights, with higher adjustment accuracy. The tuner can do a better job and give customers a satisfactory key touch feeling.

[0061] In addition, a piano measurement and adjustment method using the piano adjustment gauge further includes step S30: measuring the disconnection distance;

[0062] Place the outer side surface (the side surface outside the groove) of the first measuring plate or the second measuring plate against the strings, and the inner side surface (one end surface inside the groove) of the first measuring plate or the second measuring plate faces the hammer, press the key so that the top rod of the piano is about to disengage from the cam of the hammer, and measure the distance from the hammer to the string (i.e., the disconnection distance).

[0063] In the present application, measuring plates of different thicknesses can be used to measure disconnection distances in different pitch zones, and the setting of the middle groove allows the (blind) tuner to avoid the nearby hammers when touching them with his fingers, which makes the operation very convenient.

[0064] When the key touches the bottom, the thrust on the hammer disappears, and it instantly completes a very small free throw Let-Off process and falls back. Disconnection is an "escapement structure" that can affect the sound quality of the piano. The disconnection time of the hammer can be adjusted by changing the time when the top rod of the linkage device in the piano is separated from the cam of the hammer. Press the key so that the top rod is about to separate from the cam of the hammer. At this time, the distance between the hammer and the string is the disconnection distance. The disconnection distance is different in different tone ranges. The disconnection distance in the treble range is smaller, while the disconnection distance in the bass range is larger. While slowly pressing the key and observing the hammer, the size of the disconnection distance can be corrected by adjusting the retraction screw.

[0065] Furthermore, the method further comprises step S31, touch measurement of the height of the black keys of the keyboard;

[0066] The third measuring tool is placed on the key surface of the white key, and the rectangular part is placed against one side of the black key. The height difference between the side surface of the rectangular part and the black key is measured by touch to determine the height of the black key. Specifically, the height of the black key is measured by comparing the side length of the 12mm*12mm square of the rectangular part.

[0067] Furthermore, the method further comprises step S32, measuring the striking distance of the string;

[0068] Place the end surface (12mm*12mm surface) of the third measuring tool on one side of the rectangular parallelepiped portion against the hammer striking point, and touch and measure the distance between the end surface of the third measuring tool on one side of the special-shaped portion and the string.

[0069] Furthermore, the method further comprises step S33, adjusting the start time of the mute device;

[0070] Place the end surface (12mm*12mm surface) of the third measuring tool on one side of the rectangular parallelepiped portion against the strings, and touch and measure the distance between the end surface of the third measuring tool on one side of the special-shaped portion and the point where the hammer strikes the string.

[0071] Among them, the scale lines (marking lines) on the side of the rectangular body also help the tuner to more accurately grasp the activation time of the silencer.

[0072] The arrangement of the groove makes it easy for the ends of the first measuring plate and the second measuring plate to abut against the adjacent hammers of the hammer to be measured, and the hammer to be measured extends into the groove and gradually approaches one side end face of the rectangular parallelepiped portion in the groove, thereby making it easy for the blind tuner to grasp the third measuring tool and measure by touch.

[0073] The present application also discloses a method for measuring and adjusting an upright piano using the piano adjustment gauge, which comprises the following steps:

[0074] L10. Place the first gauge on its side on the lower locking plane, with the right-angle detection surface of the first gauge against the front elevation of the front end of the white key. Use the upper side of the first gauge to calibrate the height and parallelism of the front end of the key. If the white key surface is tilted, use the flat surface of the second or third gauge to press against the top of the middle pin from one side of the tilt direction, and gently tap it to the opposite side of the tilt direction to restore the white key surface to a level state; thereby achieving full leveling of the white key surface and adjusting the height of all white keys to a consistent level.

[0075] L20. Measure the distance from the tip of the hammer to the string using the first gauge or the third gauge;

[0076] If the striking distance is too wide, you can add (stick) a layer of felt on the inside of the hammer back, or pad the three supporting points of the hammer back with felt blocks of appropriate thickness, so that the back moves forward a little, thereby shortening the striking distance of all the hammers (by accurately adjusting the striking distance required by the piano, personalized customization services can be provided for players with different touch requirements);

[0077] If the striking distance is too narrow, replace the thin felt on the three supporting points of the hammer back guard to make the back guard move back a proper distance; adjust the hammer back guard screw to try to make the hammer back guard move back;

[0078] L30. Using the first measuring tool and the third measuring tool to adjust the sinking depth of the front end of the white key, specifically comprising the steps of:

[0079] L31 uses the height of the front detection surface of the first measuring tool as the standard of the sinking depth of the front end of the white key;

[0080] Place the inclined detection surface of the first measuring tool downward against the white key to be tested, with the right-angle detection surface facing upward, so that the front detection surface of the first measuring tool is flush with the front vertical surface (outer end surface) of the white key to be tested; press the white key to be tested with force (medium force, about 200g weight), so that the white key to be tested moves in an arc with the middle pin as the fulcrum, and judge the sinking depth of the front end of the white key to be tested by comparing the height difference between the right-angle detection surface and the keys on the two adjacent sides of the white key to be tested;

[0081] If the front end of the white key sinks too deep or too shallow, adjust it by adding or removing the large paper ring on the front pin until the right-angle detection surface is flush with the top of the keys on both sides of the white key being detected;

[0082] L32. The height of the front detection surface of the first measuring tool is superimposed on the thickness of the first measuring plate or the second measuring plate of the third measuring tool as the front end sinking depth standard of the white key;

[0083] Place the oblique detection surface of the first measuring tool downward against the white key to be tested, with the right-angle detection surface facing upward, so that the front detection surface of the first measuring tool is flush with the front vertical surface (outer end surface) of the white key to be tested; stack the first measuring plate or the second measuring plate of the third measuring tool on the right-angle detection surface; press the white key to be tested with force (medium force, about 200g weight), so that the white key to be tested moves in an arc with the middle pin as the fulcrum, and judge the sinking depth of the front end of the white key to be tested by comparing the height difference between the plane on the first measuring plate or the second measuring plate and the keys on the two adjacent sides of the white key to be tested;

[0084] If the front end of the white key sinks too deep or too shallow, adjust it by adding or removing the large paper ring on the front pin until the plane on the first measuring board or the second measuring board is flush with the top of the keys on both sides of the white key being tested.

[0085] L40. Use the third gauge to adjust the black key sinking depth

[0086] The first measuring plate or the second measuring plate of the third measuring tool is placed against the upper plane of the white key, and the sinking depth of the black key is adjusted and unified by using the thickness of the first measuring plate or the second measuring plate;

[0087] That is, all black keys sink under the same medium force (200g weight) and are higher than the upper plane of the white keys by the thickness of a first measuring plate or a second measuring plate;

[0088] The specific adjustment method is the same as that of the white keys, and adjustment is made by increasing or decreasing the large paper ring on the front pin.

[0089] Furthermore, step L10 further includes:

[0090] Step L11. Place the first test plate (thickness 1.5mm) or the second test plate (thickness 2mm) of the third measuring tool flat on the upper plane of the lower lock stop, place the first measuring tool sideways on the first test plate (thickness 1.5mm) or the second test plate (thickness 2mm), and place the right-angled test surface of the first measuring tool against the front elevation of the front end of the white key. Use the upper side of the first measuring tool to calibrate the height and parallelism of the front end of the white key;

[0091] If the overall height of the white keys does not meet this standard, you can make overall adjustments by changing the height of the middle sleeper; fully loosen the fixing screws at each part of the middle sleeper and add or remove paper or wood pieces of appropriate thickness near the screws at each fulcrum below it; if individual white keys are uneven or do not form a horizontal line, adjust them by adding or removing the small paper rings under the felt rings of the middle pins;

[0092] In a static state, the upper plane of the white key should be between 20mm and 22mm higher than the lower lock stop plane. This application uses the superimposed measurement of the third measuring tool and the first measuring tool to enable blind tuners to be more accurate in touch measurement.

[0093] Step L12. The lower measuring surface of the second measuring tool is placed against the upper plane of the white key, and the height of the black key is measured by comparison using the sink detection surface or the upper measuring surface; the inclination of the black key plane and the uneven key gap are eliminated by adding or removing the small paper ring under the felt ring of the middle pin.

[0094] Furthermore, the method further comprises step L50 of adjusting the disconnection distance;

[0095] Place the outer side surface (the side surface outside the groove) of the first measuring plate or the second measuring plate of the third measuring tool against the strings, and the inner side surface (one end surface in the groove) of the first measuring plate or the second measuring plate faces the hammer, press the key, make the top rod of the piano in a position about to leave the cam of the hammer, and measure the distance from the hammer to the string (the standard of this distance is: 2mm in the lowest pitch range, gradually transitioning to 1.5mm towards the highest pitch range);

[0096] Use the real adjustment lever to vertically cover the real adjustment (adjuster) screw to be adjusted, and gently turn it to adjust; to reduce the disconnection distance, turn it counterclockwise to raise the real adjustment knob; to increase the disconnection distance, turn it clockwise to lower the real adjustment knob;

[0097] During the adjustment process, one end face of the first measuring tool in the length direction (length 45-50mm, preferably 46mm) is placed against the back stop of the hammer, and the other end face of the first measuring tool in the length direction is facing the tail of the hammer. The distance between the tail of the hammer and the back stop of the hammer is always observed to prevent the distance from changing.

[0098] Furthermore, the method further comprises step L60, adjusting the return distance;

[0099] Place the lower measuring surface of the second measuring tool against the strings, play the keys, and measure the distance between the hammer corresponding to the played keys and the detection surface of the sinker when the hammer is in the receiving state, and the measured distance is the return distance;

[0100] Alternatively, a first measuring plate or a second measuring plate is stacked on the detection surface of the sink table, and the distance between the string hammer and the first measuring plate or the second measuring plate when the string hammer is in the receiving state is measured, and the measured distance is the return distance;

[0101] When the return distance is too large or too small, it can be adjusted by pushing and pulling the bent support metal rod forward and backward.

[0102] Specifically, hold up and fix the linkage with the thumb and index finger of one hand, and grab the stopper with the other hand and push forward or pull back. After adjustment, observe from the side that all the stoppers should remain in a straight line; if the return stroke is uneven, it means that the key sinking depth is inconsistent, and the key sinking depth should be adjusted at the same time.

[0103] After striking the string, the hammer retreats and stops at an appropriate position halfway to facilitate the correct reset of the various parts of the action mechanism and the next string strike. When the hammer stops halfway, the distance between its tip (the striking surface) and the string is called the "return stroke".

[0104] Furthermore, the method further comprises step L70, adjusting the spoon nails;

[0105] Use the 24mm, 18mm, 20mm, and 22mm scale lines (marking lines) on the second gauge for comparison and adjustment, or use the 15mm of the second gauge and the 20mm of the first gauge for direct comparison and measurement. Since the spoon nail on the linkage needs to be aligned with the corresponding damper lever, there must be different bending directions and angles in each tone area. The bending direction of the spoon nail is: the bass and treble areas are tilted to the right, and the middle area is tilted to the left. When making adjustments in the bass and treble areas, use your left hand to fix the linkage, hold the spoon nail plate with your right hand, and insert it from the right side of the linkage to be adjusted. The middle area is the opposite. After the spoon nail is hung on the top plate, press the handle down to delay the damper from leaving the string; lift it up to advance the damper from leaving the string.

[0106] The present application also discloses a method for measuring and adjusting a grand piano using the piano adjustment gauge, which comprises the following steps:

[0107] J10. The second gauge is placed sideways on the piano shelf, and the distance from the front edge of the white key to the shelf is measured using the 65mm length or 64mm width of the second gauge;

[0108] Place the first measuring tool sideways on the upper plane of the keyboard frame, and use the length of the first measuring tool to measure the distance from the upper plane of the white keys to the upper plane of the keyboard frame;

[0109] Place the third measuring tool on the upper plane of the white key, and use the height of the cross section of the rectangular parallelepiped portion of the third measuring tool to measure the distance from the upper plane of the front end of the black key to the upper plane of the white key;

[0110] When the above distance is too large or too small, it can be adjusted by adding or removing paper rings of appropriate thickness on the front pin;

[0111] J20. Place the keyboard mechanism on the platform, place the two ends of the second gauge in length or width between the bottom of the tuning frame and the hammer, set the string height on the tuning frame, use the horizontal ruler as the string, and align the hammer at the top; slowly press the keys, the double vibration rod and the top rod jointly push the hammer up, before reaching the disconnection point, the front end of the double vibration rod should be blocked by the height limit screw to stop it from rising; continue to push the hammer to the disconnection position independently by the top rod; the hammer cannot strike the string due to insufficient inertia; continue to press the keys, the top rod bend is blocked by the tuning knob, the upper end is tripped forward and separated from the bottom of the drum wheel; the hammer loses the support of the top rod, and falls down by its own weight, and the drum wheel is supported by the double vibration rod waiting below, forming a fall distance of 2mm from the disconnection point downward;

[0112] Use the thickness of the second measuring plate (2mm thickness) of the third measuring tool for comparative measurement. If the fall-back distance is too small or does not exist, it means that the compound vibration rod has risen too much, directly pushing the hammer to (or even higher than) the disconnection position, causing abnormal string contact or continuous hitting. If the fall-back distance is too large, it means that the compound vibration rod stopped rising too early. When the machinery is reset, the top rod will find it difficult to return smoothly to the bottom of the drum wheel, and the hammer will find it difficult to strike the string continuously, affecting the effect of fast vibration and playing the weakest note.

[0113] When the hammer is disconnected (no string is struck) when the key is pressed slowly, it falls to the appropriate position to ensure that the action works quickly and agilely. When the hammer does not have enough return force when playing soft notes, there is also space for it to fall off the string quickly to ensure the continuous vibration and pronunciation of the string.

[0114] J30. The tuner stands in front of the keyboard and presses the key with medium force without lifting it. After the hammer strikes the string, it falls rapidly due to the reaction force. Its tail is held by the stopper, forming the return stroke of the hammer. At this time, the correct distance between the tip of the hammer and the bottom of the string should be 15mm.

[0115] Place the lower measuring surface of the second gauge against the bottom of the tuning stand horizontal ruler (set string height), and measure the distance between the upper measuring surface of the second gauge and the tip of the hammer;

[0116] If there is a gap between the tip of the hammer and the upper measuring surface of the second gauge when putting it back after striking the string, it means that the return distance is too large; if the upper measuring surface of the second gauge presses down the hammer when putting it back after striking the string, it means that the distance is too small; if the tip of the hammer just contacts the upper measuring surface of the second gauge, the tightness is appropriate and the return distance meets the standard.

[0117] By adopting the above technical solution, the present invention has the following beneficial effects:

[0118] The piano adjustment measuring tool provided by the present invention is specially designed for piano tuning. It is composed of three separate measuring tools, which can be used separately or in combination for adjustment and comparison. It provides a basis for the tuning and adjustment of all parameters in the piano mechanical adjustment process. After testing, this set of measuring tools covers all parameters of all keyboard mechanical adjustments such as piano striking distance, keyboard height, sinking depth, disconnection distance, hammer return, hammer fall, and silencer start time, which greatly improves the speed and efficiency of piano tuning. In terms of accuracy, through the combined use of several measuring tools, the accuracy of various adjustment parameters is higher and the error is smaller. In addition, the careful design of the measuring tool shape makes the measuring tool easy to use in the piano adjustment operation, and in the dense arrangement of the parts of the string machine, it can effectively bypass obstacles and measure various data. The design of this set of measuring tools enables piano tuners to complete piano tuning and adjustment work more scientifically, accurately, efficiently and comprehensively, which is the first of its kind in domestic piano tuning tools.

[0119] At the same time, this set of measuring tools is also suitable for the teaching of music students. It provides a more scientific basis and auxiliary means for students to adjust, touch and compare in the process of piano tuning, making teaching more effective and students mastering this skill more accurately and efficiently. The uniqueness of this set of measuring tools also lies in: three sets of measuring tools are made of three different materials: 1 set of mahogany material, 1 set of organic material, and 1 set of metal material. This multi-material design is also the first in China, which is convenient for piano tuners to choose to use under different climates, different temperatures, and different humidity conditions. It is especially suitable for the adjustment and testing of pianos for high-end concerts and concerts. It greatly improves the accuracy and efficiency of piano tuning. From concept to design, this set of piano tuning measuring tools has set a precedent in domestic piano tuning tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0120] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0121] Figure 1 A three-dimensional diagram of a first measuring tool provided in an embodiment of the present invention;

[0122] Figure 2 for Figure 1 A view of the first measuring tool shown;

[0123] Figure 3A three-dimensional diagram of a second measuring tool provided in an embodiment of the present invention;

[0124] Figure 4 A three-dimensional diagram of a third measuring tool provided in an embodiment of the present invention;

[0125] Figure 5 It is a left side view of the third measuring tool provided in the embodiment of the present invention;

[0126] Figure 6 It is a right side view of the third measuring tool provided in the embodiment of the present invention;

[0127] Figure 7 It is a principle diagram of measuring the sinking depth of the front end of a white key in an embodiment of the present invention. DETAILED DESCRIPTION

[0128] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0129] The present invention is further explained below in conjunction with specific implementation modes.

[0130] Example 1

[0131] like Figure 1-2 As shown, a piano adjustment measuring tool provided in this embodiment includes: a first measuring tool 10;

[0132] The first measuring tool 10 is in the shape of a trapezoidal block as a whole;

[0133] The shape of the first measuring tool 10 in a first cross section parallel to the xy projection plane is a rectangle;

[0134] The shape of the first measuring tool 10 on the second cross section parallel to the yz projection plane is a right-angled trapezoid; the plane on the first measuring tool 10 that is parallel to the xz projection plane and includes the right-angled waistline of the right-angled trapezoid is the right-angled detection surface 11; the surface that faces the right-angled detection surface 11 up and down and includes the oblique waistline of the right-angled trapezoid is the oblique detection surface 12;

[0135] The first measuring tool 10 comprises a front end detection surface 13 and a rear end detection surface 14 respectively arranged parallel to each other at both ends in the z-axis direction;

[0136] The front detection surface 13 is a rectangle with a width of 20 mm and a height of 10.5 mm. The front detection surface 13 and the rear detection surface 14 have the same width. The rear detection surface 14 is a rectangle with a width of 20 mm and a height of 8.3 mm.

[0137] For ease of expression, this application uses a three-dimensional coordinate system to define directions, where the Z-axis direction is parallel to each piano key, the y-axis direction is the up and down height direction, the x-axis direction is the left and right direction, the side of the piano or measuring tool close to the person is the front side or front end, and the side away from the person is the back side or rear end.

[0138] The length of the first measuring tool 10, that is, the height of the right-angled trapezoid, is 46 mm.

[0139] The first measuring tool 10 is made of red wood, organic material or metal material, so that piano tuners can choose to use it in different climates, different temperatures or different humidity conditions.

[0140] The first measuring tool can be used independently or in combination with other measuring tools for all parameters of all keyboard mechanical adjustments, such as piano striking distance, keyboard height, sinking depth, disconnection distance, hammer return, hammer fall, and muffler start time, greatly improving the speed and efficiency of piano tuning.

[0141] Example 2

[0142] like Figure 3 As shown, a piano adjustment gauge provided in this embodiment includes: a second gauge 20; the second gauge 20 is in a rectangular shape as a whole, including: an upper measuring surface 21 and a lower measuring surface 22; the upper measuring surface 21 and the lower measuring surface 22 are parallel to each other, and the distance between the two is 15mm; a sinking platform 23 is provided at one end of the upper measuring surface 21, and the sinking platform 23 includes a sinking platform detection surface 24 parallel to the lower measuring surface 22, and the distance between the sinking platform detection surface 24 and the lower measuring surface 22 is 13mm. That is, the height of the sinking platform 23 is 2mm.

[0143] The design of the sinker 23 with a recess of nearly 2mm can better fit the white keys of the grand piano to measure the height and key level of the grand piano keyboard. Generally, when the lower lock of the grand piano is removed, there will be a height difference between the front end of the keyboard and the place where the measuring tool is placed at the front edge of the shelf. The recess of nearly 2mm perfectly solves this problem.

[0144] Furthermore, the second measuring tool 20 has a length of 65 mm and an overall width of 64 mm, that is, the lower measuring surface 22 is a rectangular surface with a length of 65 mm and a width of 64 mm.

[0145] Furthermore, the length of the sinking platform 23 or the sinking platform detection surface 24 is 65 mm, and the width is 12 mm; the length of the upper measuring surface 21 is 65 mm, and the width is 52 mm.

[0146] Furthermore, the second measuring tool 20 is made of mahogany, organic material or metal material, so that piano tuners can choose to use it in different climates, different temperatures or different humidity conditions.

[0147] The second measuring tool can be used independently or in combination with other measuring tools to measure all parameters of all keyboard mechanical adjustments, including piano striking distance, keyboard height, sinking depth, disconnection distance, hammer return, hammer fall, and muffler start time, greatly improving the speed and efficiency of piano tuning.

[0148] Example 3

[0149] like Figure 4-6 As shown, a piano adjustment gauge provided in this embodiment includes: a third gauge 30; the third gauge 30 includes a special-shaped portion 31 and a rectangular parallelepiped portion 32; the cross section of the special-shaped portion 31 is V-shaped, including a first measuring plate 31a and a second measuring plate 31b, the thickness of the first measuring plate 31a is 1.5mm; the thickness of the second measuring plate 31b is 2mm. The angle between the first measuring plate 31a and the second measuring plate 31b is 90°. The cross section of the rectangular parallelepiped portion 32 is a square of 12mm*12mm.

[0150] In other words, the third measuring tool 30 is in the shape of a cylinder as a whole, and the cross section of the cylinder is a square; a groove 33 with a rectangular cross section is provided at one end of the cylinder; the corresponding part of the groove 33 on the cylinder is the special-shaped part 31 (the two plate-shaped bodies surrounding the groove 33 are the first measuring plate 31a and the second measuring plate 31b respectively), and the non-groove 33 part of the cylinder is the rectangular parallelepiped part 32.

[0151] The third measuring tool 30 has an overall length of 48 mm, the rectangular parallelepiped portion 32 has a length of 24 mm, and the groove 33 and the shaped portion 31 have a length of 24 mm. The outer surface of the rectangular parallelepiped portion 32 is provided with scale lines 34 for marking the distance from one end surface of the rectangular parallelepiped. The scale lines include at least 18 mm, 20 mm and / or 22 mm scale lines.

[0152] The third measuring tool can be used independently or in combination with other measuring tools for all parameters of all keyboard mechanical adjustments, including piano striking distance, keyboard height, sinking depth, disconnection distance, hammer return, hammer fall, and muffler start time, greatly improving the speed and efficiency of piano tuning.

[0153] Example 4

[0154] This embodiment provides a piano measurement and adjustment method using the piano adjustment gauge described in Embodiments 1-3, which specifically includes the following steps:

[0155] Step S10, measuring the sinking depth of the front end of the white key

[0156] like Figure 7As shown, the inclined detection surface 12 of the first measuring tool 10 is pressed downward against the white key 40 to be tested, the right-angle detection surface 11 is upward, and the front end detection surface 13 of the first measuring tool 10 is flush with the front vertical surface (outer end surface) of the white key 40 to be tested; the white key to be tested is pressed with force (the force is the medium force of a weight of about 200g when a pianist usually plays), and the white key to be tested moves in an arc with the middle pin as the fulcrum, and the sinking depth of the front end of the white key 40 to be tested is determined by comparing the height difference between the right-angle detection surface 11 and the keys 41 on both sides adjacent to the white key to be tested.

[0157] When the right-angle detection surface 11 is higher than a certain measurement value (visual measurement value or tool measurement value) on the adjacent keys on both sides, the front end sinking depth of the detected white key is the difference between the height of the front end detection surface 13 and the measurement value; when the right-angle detection surface 11 is lower than a certain measurement value (visual measurement value, touch measurement value or tool measurement value) on the adjacent keys on both sides, the front end sinking depth of the detected white key is the sum of the height of the front end detection surface 13 and the measurement value;

[0158] Step S11, adjustment of the sinking depth of the front end of the white key

[0159] If the front end of the white key sinks too deep or too shallow, it can be adjusted by adding or removing the large paper ring on the front pin. Adjusting the sinking depth of the white key by adding or removing the large paper ring on the front pin is a common method used by existing tuners and will not be described in detail here.

[0160] When adding or removing paper rings, try to use thick paper rings instead of multiple thin paper rings, and follow the principle of thick paper rings at the bottom and thin paper rings at the top.

[0161] For example, the front end sinking depth of the pre-adjusted white key is 10.5mm, and the height of the front end detection surface 13 is 10.5mm. When the paper ring is added or removed until the pre-adjusted white key is pressed down with a medium force (or a 200g weight is used to press down), the right-angle detection surface 11 is flush with the upper surfaces of the adjacent keys on both sides.

[0162] After a certain amount of training, a piano tuner (including a blind piano tuner) can adjust the first measuring tool 10 to any sinking depth between 9.5 mm and 11.5 mm with an error of less than 0.1 mm.

[0163] Furthermore, this embodiment also includes step S12:

[0164] The inclined detection surface 12 of the first measuring tool 10 is placed downward against the white key to be inspected, the right-angle detection surface 11 is facing upward, and the front detection surface 13 of the first measuring tool 10 is flush with the front elevation (outer end surface) of the white key to be inspected; the upper edge of the front detection surface 13 (the corner edge between the front detection surface 13 and the right-angle detection surface 11) is flush with the keys on the two adjacent sides of the white key to be inspected, and when there is a height difference between the upper edge of the rear detection surface 14 (the corner edge between the rear detection surface 14 and the right-angle detection surface 11) and the keys on the two adjacent sides of the white key to be inspected, it indicates that the key has wood deformation. For example, a blind tuner can judge whether the key has wood deformation by touching the height difference between the front and rear ends of the right-angle detection surface 11 and the keys on the two adjacent sides.

[0165] Furthermore, the method further comprises step S13:

[0166] When the wood of the piano key is deformed, the height difference between the upper edge of the rear end detection surface 14 (the corner edge between the rear end detection surface 14 and the right-angle detection surface 11) and the upper surface of the keys on both sides of the white key being detected is used to determine the sinking depth of the white key being detected.

[0167] The specific measurement and adjustment method is the same as the measurement and adjustment of the front end sinking depth.

[0168] Furthermore, the method further comprises step S14, measuring the height of the upright piano keyboard;

[0169] The right-angle detection surface 11 is placed horizontally against the front elevation of the key, and the key height can be determined by touch comparison. Specifically, when the first measuring tool 10 is 20 mm thick, that is, the front detection surface 13 and the rear detection surface 14 are 20 mm wide, the key height can be determined by comparing the thickness of the key with the first measuring tool 10. Experiments have shown that after practice, blind tuners can use the first measuring tool 10 to determine and adjust any key height between 18 mm and 22 mm, laying a good foundation for a good residual touch.

[0170] Furthermore, the method further comprises step S15, measuring the striking distance of the string;

[0171] The front detection surface 13 of the first measuring tool 10 is placed against the strings, and the distance between the rear detection surface 14 and the striking point of the tip of the hammer is measured (touch), thereby measuring the striking distance of each hammer. That is, by using the length of the first measuring tool 10 as a scale, the striking distance of each hammer can be measured and determined by comparison; and the striking distance is the basis of all mechanical adjustments.

[0172] Example 5

[0173] The piano measurement and adjustment method provided by this embodiment using the piano adjustment gauge further includes step S20:

[0174] Measuring the return distance of the piano using the second measuring tool 20;

[0175] Specifically, the lower measuring surface 22 is placed against the strings, and the keys are played. The distance between the hammer corresponding to the played key and the upper measuring surface 21 or the sinking platform detection surface 24 when in the receiving state is measured, and the measured distance is the return distance.

[0176] Furthermore, when measuring the return distance of the grand piano, the upper measuring surface 21 faces the hammer, and the distance between the hammer and the upper measuring surface 21 when the hammer is in the supported state is measured (visually or by touch).

[0177] Furthermore, when measuring the return distance of the upright piano, the sinker detection surface 24 faces the hammer, and the distance between the hammer and the sinker detection surface 24 when the hammer is in the supported state is measured (visually or by touch).

[0178] Furthermore, the method further comprises step S21, measuring the height of the keyboard;

[0179] The lower measuring surface 22 is placed against the front vertical surface (outer end surface) of the key, and the lower side surface of the second measuring tool 20 is placed against the table of the mechanical adjustment frame, and the distance between the upper side surface of the second measuring tool 20 and the key surface is measured by comparison.

[0180] Among them, the requirements for grand pianos are higher and difficult to adjust. The lower measuring surface 22 is a 64mm*65mm rectangle, which can detect 64mm and 65mm keyboard heights, with higher adjustment accuracy. The tuner can complete the work better and give the customer a satisfactory key touch feeling.

[0181] Example 6

[0182] The piano measurement and adjustment method using the piano adjustment gauge provided in this embodiment further includes step S30: measuring the disconnection distance;

[0183] Place the outer side surface of the first measuring plate 31a or the second measuring plate 31b (the side surface outside the groove 33) against the strings, and the inner side surface of the first measuring plate 31a or the second measuring plate 31b (one end surface inside the groove 33) faces the hammer, press the key so that the top rod of the piano is about to separate from the cam of the hammer, and measure the distance from the hammer to the string (i.e., the disconnection distance).

[0184] In the present application, measuring plates of different thicknesses can be used to measure disconnection distances of different tone zones, and the setting of the middle groove 33 allows the (blind) tuner to avoid the nearby hammers when touching with his fingers, which makes the operation very convenient.

[0185] When the key touches the bottom, the thrust on the hammer disappears, and it instantly completes a very small free throw Let-Off process and falls back. Disconnection is an "escapement structure" that can affect the sound quality of the piano. The disconnection time of the hammer can be adjusted by changing the time when the top rod of the linkage device in the piano is separated from the cam of the hammer. Press the key so that the top rod is about to separate from the cam of the hammer. At this time, the distance between the hammer and the string is the disconnection distance. The disconnection distance is different in different tone ranges. The disconnection distance in the treble range is smaller, while the disconnection distance in the bass range is larger. While slowly pressing the key and observing the hammer, the size of the disconnection distance can be corrected by adjusting the retraction screw.

[0186] Furthermore, the method further comprises step S31, touch measurement of the height of the black keys of the keyboard;

[0187] The third measuring tool 30 is placed on the key surface of the white key, and the rectangular parallelepiped portion 32 is placed against one side of the black key. The height difference between the side surface of the rectangular parallelepiped and the black key is measured by touch to determine the height of the black key. Specifically, the height of the black key is measured by comparing the side length of the 12mm*12mm square of the rectangular parallelepiped portion 32.

[0188] Furthermore, the method further comprises step S32, measuring the striking distance of the string;

[0189] The end surface (12 mm*12 mm surface) of the third measuring tool 30 on one side of the rectangular parallelepiped portion 32 is placed against the hammer striking point, and the distance between the end surface of the third measuring tool 30 on one side of the special-shaped portion 31 and the string is measured by touch.

[0190] Furthermore, the method further comprises step S33, adjusting the start time of the mute device;

[0191] The end surface (12 mm*12 mm surface) of the third measuring tool 30 on one side of the rectangular parallelepiped portion 32 is placed against the strings, and the distance between the end surface of the third measuring tool 30 on one side of the special-shaped portion 31 and the point where the hammer strikes the string is measured by touch.

[0192] The scale lines (marking lines) on the side of the rectangular parallelepiped portion 32 also help the tuner to more accurately grasp the start time of the silencer.

[0193] The arrangement of the groove 33 facilitates the use of the ends of the first measuring plate 31a and the second measuring plate 31b to abut against the adjacent hammers of the hammer to be measured, and the hammer to be measured extends into the groove 33 and gradually approaches one side end surface of the rectangular parallelepiped portion 32 in the groove 33, thereby facilitating the blind tuner to grasp the third measuring tool 30 and touch measurement.

[0194] Example 7

[0195] The present embodiment provides a method for measuring and adjusting an upright piano using the piano adjustment gauge, which comprises the following steps:

[0196] L10. Place the first measuring tool 10 on its side on the lower locking plane, with the right-angle detection surface 11 of the first measuring tool 10 against the front elevation of the front end of the white key. Use the upper side of the first measuring tool 10 to calibrate the height and parallelism of the front end of the key. If the white key surface is tilted, use the plane of the second measuring tool 20 or the third measuring tool 30 to press against the top of the middle pin from one side of the tilt direction, and gently tap it to the opposite side of the tilt direction to restore the white key surface to the level; thereby achieving that the white key surface remains fully level and all white keys are adjusted to the same height;

[0197] L20 using the first gauge 10 or the third gauge 30 to measure the distance from the tip of the hammer to the string;

[0198] If the striking distance is too wide, you can add (stick) a layer of felt on the inside of the hammer back, or pad the three supporting points of the hammer back with felt blocks of appropriate thickness, so that the back moves forward a little, thereby shortening the striking distance of all the hammers (by accurately adjusting the striking distance required by the piano, personalized customization services can be provided for players with different touch requirements);

[0199] If the striking distance is too narrow, replace the thin felt on the three supporting points of the hammer back guard to make the back guard move back a proper distance; adjust the hammer back guard screw to try to make the hammer back guard move back;

[0200] L30. Using the first measuring tool 10 and the third measuring tool 30 to adjust the sinking depth of the front end of the white key, specifically comprising the steps of:

[0201] L31 takes the height of the front detection surface 13 of the first measuring tool 10 as the standard of the sinking depth of the front end of the white key;

[0202] Place the inclined detection surface 12 of the first measuring tool 10 downward against the white key to be tested, with the right-angle detection surface 11 facing upward, and the front detection surface 13 of the first measuring tool 10 flush with the front vertical surface (outer end surface) of the white key to be tested; press the white key to be tested with force (medium force, about 200g weight), and the white key to be tested moves in an arc with the middle pin as the fulcrum, and judge the sinking depth of the front end of the white key to be tested by comparing the height difference between the right-angle detection surface 11 and the keys on the two adjacent sides of the white key to be tested;

[0203] If the front end of the white key sinks too deep or too shallow, adjust it by adding or removing the large paper ring on the front pin until the right-angle detection surface 11 is flush with the top of the keys on both sides of the white key being detected;

[0204] L32. The height of the front end detection surface 13 of the first measuring tool 10 is superimposed on the thickness of the first measuring plate 31a or the second measuring plate 31b of the third measuring tool 30 as the white key front end sinking depth standard;

[0205] Place the inclined detection surface 12 of the first measuring tool 10 downward against the white key to be tested, with the right-angle detection surface 11 facing upward, and the front detection surface 13 of the first measuring tool 10 flush with the front elevation (outer end surface) of the white key to be tested; overlap the first measuring plate 31a or the second measuring plate 31b of the third measuring tool 30 on the right-angle detection surface 11; press the white key to be tested with force (medium force, about 200g weight), and the white key to be tested moves in an arc with the middle pin as the fulcrum, and judge the sinking depth of the front end of the white key to be tested by comparing the height difference between the upper plane of the first measuring plate 31a or the second measuring plate 31b and the keys on the two adjacent sides of the white key to be tested;

[0206] If the front end of the white key sinks too deep or too shallow, it can be adjusted by adding or removing the large paper ring on the front pin until the upper plane of the first measuring board 31a or the second measuring board 31b is flush with the upper surfaces of the keys on both sides of the white key being tested.

[0207] L40. Use the third measuring tool 30 to adjust the black key sinking depth

[0208] Place the first measuring plate 31a or the second measuring plate 31b of the third measuring tool 30 against the upper plane of the white keys, and use the thickness of the first measuring plate 31a or the second measuring plate 31b to adjust and unify the sinking depth of the black keys;

[0209] That is, after sinking with the same medium force (200g weight), all black keys are higher than the upper plane of the white keys by the thickness of a first measuring plate 31a or a second measuring plate 31b;

[0210] The specific adjustment method is the same as that of the white keys, and adjustment is made by increasing or decreasing the large paper ring on the front pin.

[0211] Furthermore, step L10 further includes:

[0212] Step L11. Place the first test plate (thickness 1.5 mm) or the second test plate (thickness 2 mm) of the third measuring tool 30 flat on the upper plane of the lower lock stop, place the first measuring tool 10 sideways on the first test plate (thickness 1.5 mm) or the second test plate (thickness 2 mm), and abut the right-angle test surface 11 of the first measuring tool 10 against the front elevation of the front end of the white key, and use the upper side of the first measuring tool 10 to calibrate the height and parallelism of the front end of the white key;

[0213] If the overall height of the white keys does not meet this standard, you can make overall adjustments by changing the height of the middle sleeper; fully loosen the fixing screws at each part of the middle sleeper and add or remove paper or wood pieces of appropriate thickness near the screws at each fulcrum below it; if individual white keys are uneven or do not form a horizontal line, adjust them by adding or removing the small paper rings under the felt rings of the middle pins;

[0214] In a static state, the upper plane of the white key should be between 20 mm and 22 mm higher than the lower lock stop plane. This application uses the superimposed measurement of the third measuring tool 30 and the first measuring tool 10 to enable the blind tuner to be more accurate in touch measurement.

[0215] Step L12. The lower measuring surface 22 of the second measuring tool 20 is placed against the upper plane of the white keys, and the height of the black keys is measured by comparing the sink detection surface 24 or the upper measuring surface 21; the inclination of the black key plane and the uneven key gap are eliminated by adding or removing the small paper ring under the middle pin felt ring.

[0216] Furthermore, the method further comprises step L50 of adjusting the disconnection distance;

[0217] Place the outer side surface (side surface outside the groove) of the first measuring plate 31a or the second measuring plate 31b of the third measuring tool 30 against the strings, and the inner side surface (one end surface inside the groove) of the first measuring plate 31a or the second measuring plate 31b faces the hammer, press the key, make the top rod of the piano in a position about to leave the hammer cam, and measure the distance from the hammer to the string (the standard of this distance is: 2mm in the lowest pitch range, gradually transitioning to 1.5mm towards the highest pitch range);

[0218] Use the real adjustment lever to vertically cover the real adjustment (adjuster) screw to be adjusted, and gently turn it to adjust; to reduce the disconnection distance, turn it counterclockwise to raise the real adjustment knob; to increase the disconnection distance, turn it clockwise to lower the real adjustment knob;

[0219] During the adjustment process, one end face of the first measuring tool 10 in the length direction (length 45-50mm, preferably 46mm) is placed against the back stop of the hammer, and the other end face of the first measuring tool 10 in the length direction faces the tail of the hammer. The distance between the tail of the hammer and the back stop of the hammer is always observed to prevent the distance from changing.

[0220] Furthermore, the method further comprises step L60, adjusting the return distance;

[0221] Place the lower measuring surface 22 of the second measuring tool 20 against the strings, play the keys, and measure the distance between the hammer corresponding to the played keys and the sinking platform detection surface 24 when the hammer is in the receiving state. The measured distance is the return distance.

[0222] Alternatively, the first measuring plate 31a or the second measuring plate 31b is stacked on the sinking platform detection surface 24, and the distance between the hammer and the first measuring plate 31a or the second measuring plate 31b when the hammer is in the receiving state is measured, and the measured distance is the return distance;

[0223] When the return distance is too large or too small, it can be adjusted by pushing and pulling the bent support metal rod forward and backward.

[0224] Specifically, hold up and fix the linkage with the thumb and index finger of one hand, and grab the stopper with the other hand and push forward or pull back. After adjustment, observe from the side that all the stoppers should remain in a straight line; if the return stroke is uneven, it means that the key sinking depth is inconsistent, and the key sinking depth should be adjusted at the same time.

[0225] After striking the string, the hammer retreats and stops at an appropriate position halfway to facilitate the correct reset of the various parts of the action mechanism and the next string strike. When the hammer stops halfway, the distance between its tip (the striking surface) and the string is called the "return stroke".

[0226] Furthermore, the method further comprises step L70, adjusting the spoon nails;

[0227] Use the 24mm, 18mm, 20mm, and 22mm scale lines (marking lines) on the second gauge 20 for comparison and adjustment, or use the 15mm of the second gauge 20 and the 20mm of the first gauge 10 for direct comparison and measurement. Since the spoon nail on the linkage needs to be aligned with the corresponding damper lever, different bending directions and angles are required in each tone area. The bending direction of the spoon nail is: the bass area and the treble area are tilted to the right, and the middle area is tilted to the left. When making adjustments in the bass area and the treble area, use the left hand to fix the linkage, hold the spoon nail plate with the right hand, and insert it from the right side of the linkage to be adjusted. The middle area is the opposite. After the spoon nail is hung on the top plate, press the handle downward to delay the damper from leaving the string; lift it upward to advance the damper from leaving the string.

[0228] Example 8

[0229] The present embodiment provides a method for measuring and adjusting a grand piano using the piano adjustment gauge, which comprises the following steps:

[0230] J10. The second measuring tool 20 is placed sideways on the piano shelf, and the distance from the front end of the white key to the shelf is measured using the second measuring tool 20 of 65mm in length or 64mm in width;

[0231] Place the first measuring tool 10 sideways on the upper plane of the keyboard frame, and use the length of the first measuring tool 10 to measure the distance from the upper plane of the white keys to the upper plane of the keyboard frame;

[0232] Place the third measuring tool 30 on the upper plane of the white key, and use the height of the cross section of the rectangular parallelepiped portion 32 of the third measuring tool 30 to measure the distance from the upper plane of the front end of the black key to the upper plane of the white key;

[0233] When the above distance is too large or too small, it can be adjusted by adding or removing paper rings of appropriate thickness on the front pin;

[0234] J20. Place the keyboard mechanism on the platform, place the two ends of the length or width of the second measuring tool 20 between the bottom of the tuning frame and the string hammer, set the string height on the tuning frame, use the horizontal ruler as the string, and align the string hammer at the top; slowly press the key, the double vibration rod and the top rod jointly push the string hammer to rise, before reaching the disconnection point, the front end of the double vibration rod should be blocked by the height limit screw to stop it from rising; continue to push the string hammer to the disconnection position independently by the top rod; the string hammer cannot strike the string due to insufficient inertia; continue to press the key, the top rod bend is blocked by the tuning knob, the upper end is tripped forward and separated from the bottom of the drum wheel; the string hammer loses the support of the top rod, and falls by its own weight, and the drum wheel is supported by the double vibration rod waiting below, forming a fall distance of 2mm from the disconnection point downward;

[0235] The thickness of the second measuring plate 31b (2mm thickness) of the third measuring tool 30 is used for comparative measurement. If the falling back distance is too small or does not exist, it means that the double vibration rod rises too much, directly pushing the hammer to (or even above) the disconnection position, causing abnormal string contact or continuous hitting; if the falling back distance is too large, it means that the double vibration rod stops rising too early, and when the machine is reset, the top rod will find it difficult to return smoothly to the bottom of the drum wheel, and the hammer will find it difficult to strike the string continuously, affecting the effect of fast vibration and playing the weakest note.

[0236] When the hammer is disconnected (no string is struck) when the key is pressed slowly, it falls to the appropriate position to ensure that the action works quickly and agilely. When the hammer does not have enough return force when playing soft notes, there is also space for it to fall off the string quickly to ensure the continuous vibration and pronunciation of the string.

[0237] J30. The tuner stands in front of the keyboard and presses the key with medium force without lifting it. After the hammer strikes the string, it falls rapidly due to the reaction force. Its tail is held by the stopper, forming the return stroke of the hammer. At this time, the correct distance between the tip of the hammer and the bottom of the string should be 15mm.

[0238] Place the lower measuring surface 22 of the second measuring tool 20 against the bottom of the horizontal ruler of the tuning frame (the set string height), and measure the distance between the upper measuring surface 21 of the second measuring tool 20 and the tip of the hammer;

[0239] When the string is put in after striking the string, if there is a gap between the tip of the hammer and the upper measuring surface 21 of the second gauge 20, it means that the return distance is too large; when the string is put in after striking the string, if the upper measuring surface 21 of the second gauge 20 presses down the hammer, it means that the distance is too small; if the tip of the hammer just contacts the upper measuring surface 21 of the second gauge 20, the tightness is appropriate and the return distance meets the standard.

[0240] The piano adjustment measuring tool provided by the present invention is specially designed for piano tuning. It is composed of three separate measuring tools, which can be used separately or in combination for adjustment and comparison. It provides a basis for the tuning and adjustment of all parameters in the piano mechanical adjustment process. After testing, this set of measuring tools covers all parameters of all keyboard mechanical adjustments such as piano striking distance, keyboard height, sinking depth, disconnection distance, hammer return, hammer fall, and silencer start time, which greatly improves the speed and efficiency of piano tuning. In terms of accuracy, through the combined use of several measuring tools, the accuracy of various adjustment parameters is higher and the error is smaller. In addition, the careful design of the measuring tool shape makes the measuring tool easy to use in the piano adjustment operation, and in the dense arrangement of the parts of the string machine, it can effectively bypass obstacles and measure various data. The design of this set of measuring tools enables piano tuners to complete piano tuning and adjustment work more scientifically, accurately, efficiently and comprehensively, which is the first of its kind in domestic piano tuning tools.

[0241] At the same time, this set of measuring tools is also suitable for the teaching of music students. It provides a more scientific basis and auxiliary means for students to adjust, touch and compare in the process of piano tuning, making teaching more effective and students mastering this skill more accurately and efficiently. The uniqueness of this set of measuring tools also lies in: three sets of measuring tools are made of three different materials: 1 set of mahogany material, 1 set of organic material, and 1 set of metal material. This multi-material design is also the first in China, which is convenient for piano tuners to choose to use under different climates, different temperatures, and different humidity conditions. It is especially suitable for the adjustment and testing of pianos for high-end concerts and concerts. It greatly improves the accuracy and efficiency of piano tuning. From concept to design, this set of piano tuning measuring tools has set a precedent in domestic piano tuning tools.

[0242] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A piano adjustment gauge, characterized in that: include: a first gage, a second gage, and a third gage; The first measuring tool is in the shape of a trapezoidal block as a whole; The shape of the first measuring tool in a first cross section parallel to the xy projection plane is a rectangle; The shape of the first measuring tool on the second cross section parallel to the yz projection plane is a right-angled trapezoid; the plane on the first measuring tool that is parallel to the xz projection plane and contains the right-angled waistline of the right-angled trapezoid is the right-angled detection surface; the surface that faces the right-angled detection surface and contains the oblique waistline of the right-angled trapezoid is the oblique detection surface; The first measuring tool comprises a front end detection surface and a rear end detection surface respectively arranged parallel to each other at two ends in the z-axis direction; The front detection surface is a rectangle with a width of 18mm-22mm and a height of 9.5mm-11.5mm; The second measuring tool is in the shape of a rectangular block as a whole, including: an upper measuring surface and a lower measuring surface; the upper measuring surface and the lower measuring surface are parallel to each other, and the distance between the two is 15 mm; a sinking platform is provided at one end of the upper measuring surface, and the sinking platform includes a sinking platform detection surface parallel to the lower measuring surface, and the distance between the sinking platform detection surface and the lower measuring surface is 13 mm; that is, the height of the sinking platform is 2 mm; The second gauge has a length of 65 mm and an overall width of 64 mm; The third measuring tool comprises a special-shaped portion; the cross section of the special-shaped portion is V-shaped, comprising a first measuring plate and a second measuring plate arranged at an angle, the thickness of the first measuring plate is 1.5 mm; the thickness of the second measuring plate is 2 mm; The angle between the first measuring plate and the second measuring plate is 90°; The third measuring tool also includes a rectangular parallelepiped portion; the cross-section of the rectangular parallelepiped portion is a square with a height of 12 mm and a width of 12 mm, and scale lines are arranged on the outer surface of the rectangular parallelepiped portion to mark the distance from the end surface of one side of the rectangular parallelepiped.

2. The piano adjustment gauge according to claim 1, characterized in that: The gradient of the oblique detection surface is 23:22; The front detection surface is a rectangle with a width of 20 mm and a height of 10.5 mm; The rear end detection surface is a rectangle with a width of 20 mm and a height of 8.3 mm; The length of the first measuring tool is 46 mm or 48 mm, that is, the height of the right-angled trapezoid is 46 mm or 48 mm.

3. The piano adjustment gauge according to claim 1, characterized in that: The third measuring tool is in the shape of a cylinder as a whole, and the cylinder has a square cross section; a groove with a rectangular cross section is provided at one end of the cylinder; the corresponding part of the groove on the cylinder is the special-shaped part, and the non-groove part on the cylinder is the cuboid part; The overall length of the third measuring tool is 48 mm, the length of the rectangular parallelepiped portion is 24 mm; the length of the groove and the special-shaped portion is 24 mm.

4. A method for measuring and adjusting an upright piano using the piano adjustment gauge according to claim 3, characterized in that: It includes the following steps: L10. Place the first gauge on its side on the lower locking plane, with the right-angle detection surface of the first gauge against the front elevation of the front end of the white key. Use the upper side of the first gauge to calibrate the height and parallelism of the front end of the key. If the white key surface is tilted, use the flat surface of the second or third gauge to press against the top of the middle pin from one side of the tilt direction, and gently tap it to the opposite side of the tilt direction to restore the white key surface to a level state; thereby achieving full leveling of the white key surface and adjusting the height of all white keys to a consistent level. L20. Measure the distance from the tip of the hammer to the string using the first gauge or the third gauge; If the striking distance is too wide, add a layer of felt on the inside of the hammer back guard or add felt blocks of appropriate thickness on the three supporting points of the hammer back guard to move the back guard forward a little, thereby shortening the striking distance of all hammers. If the striking distance is too narrow, replace the thin felt on the three supporting points of the hammer back guard to make the back guard move back a proper distance; adjust the hammer back guard screw to try to make the hammer back guard move back; L30. Using the first measuring tool and the third measuring tool to adjust the sinking depth of the front end of the white key, specifically comprising the steps of: L31 uses the height of the front detection surface of the first measuring tool as the standard of the sinking depth of the front end of the white key; The inclined detection surface of the first measuring tool is placed downward against the white key to be tested, and the right-angle detection surface is placed upward, so that the front detection surface of the first measuring tool is flush with the front vertical surface of the white key to be tested; the white key to be tested is pressed hard, and the white key to be tested moves in an arc with the middle pin as a fulcrum, and the sinking depth of the front end of the white key to be tested is determined by comparing the height difference between the right-angle detection surface and the keys on the two adjacent sides of the white key to be tested; If the front end of the white key sinks too deep or too shallow, adjust it by adding or removing the large paper ring on the front pin until the right-angle detection surface is flush with the top of the keys on both sides of the white key being detected; L32. The height of the front detection surface of the first measuring tool is superimposed on the thickness of the first measuring plate or the second measuring plate of the third measuring tool as the front end sinking depth standard of the white key; Place the oblique detection surface of the first measuring tool downward against the white key to be tested, with the right-angle detection surface facing upward, so that the front detection surface of the first measuring tool is flush with the front vertical surface of the white key to be tested; overlap the first measuring plate or the second measuring plate of the third measuring tool on the right-angle detection surface; press the white key to be tested hard, so that the white key to be tested moves in an arc with the middle pin as the fulcrum, and judge the sinking depth of the front end of the white key to be tested by comparing the height difference between the plane on the first measuring plate or the second measuring plate and the keys on the two adjacent sides of the white key to be tested; If the front end of the white key sinks too deep or too shallow, adjust it by adding or removing the large paper ring on the front pin until the plane on the first measuring plate or the second measuring plate is flush with the top of the keys on both sides of the white key being tested; L40. Use the third gauge to adjust the black key sinking depth The first measuring plate or the second measuring plate of the third measuring tool is placed against the upper plane of the white key, and the sinking depth of the black key is adjusted and unified by using the thickness of the first measuring plate or the second measuring plate; That is, after sinking with the same medium force, all the black keys are higher than the upper plane of the white keys by the thickness of a first measuring plate or a second measuring plate.

5. The upright piano measurement and adjustment method according to claim 4, characterized in that: Step L10 further comprises: Step L11. Place the first test plate or the second test plate of the third measuring tool flat on the upper plane of the lower lock stop, place the first measuring tool sideways on the first test plate or the second test plate, and place the right-angle test surface of the first measuring tool against the front elevation of the front end of the white key. Use the upper side of the first measuring tool to calibrate the height and parallelism of the front end of the white key; If the overall height of the white keys does not meet this standard, adjust the overall height by changing the middle sleeper; loosen the fixing screws at each part of the middle sleeper and add or remove paper or wood pieces of appropriate thickness near the screws at each supporting point below it; if individual white keys are uneven or do not form a horizontal line, adjust by adding or removing the small paper ring under the felt ring of the middle pin; In static state, the upper plane of the white key should be between 20mm and 22mm higher than the lower lock stop plane; Step L12. The lower measuring surface of the second measuring tool is placed against the upper plane of the white key, and the height of the black key is measured by comparison using the sink detection surface or the upper measuring surface; the inclination of the black key plane and the uneven key gap are eliminated by adding or removing the small paper ring under the felt ring of the middle pin.

6. The upright piano measurement and adjustment method according to claim 4, characterized in that: The step L50 is also included, adjusting the disconnection distance; The outer side surface of the first measuring plate or the second measuring plate of the third measuring tool is placed against the strings, and the inner side surface of the first measuring plate or the second measuring plate is facing the hammers, and the keys are pressed so that the top rod of the piano is about to leave the cam of the hammer, and the distance from the hammers to the strings is measured; Use the adjustment lever to vertically cover the adjustment screw to be adjusted, and gently turn it to adjust; To shorten the disconnection distance, turn the knob counterclockwise to raise it. To increase the disconnection distance, turn the knob clockwise to lower it. During the adjustment process, one end face of the first measuring tool in the length direction is placed against the back stop of the hammer, and the other end face of the first measuring tool in the length direction is facing the tail of the hammer. The distance between the tail of the hammer and the back stop of the hammer is always observed to prevent the distance from changing.

7. The upright piano measurement and adjustment method according to claim 4, characterized in that: The step L60 is also included, adjusting the return distance; Place the lower measuring surface of the second measuring tool against the strings, play the keys, and measure the distance between the hammer corresponding to the played keys and the detection surface of the sinker when the hammer is in the receiving state, and the measured distance is the return distance; Alternatively, a first measuring plate or a second measuring plate is stacked on the detection surface of the sink table, and the distance between the string hammer and the first measuring plate or the second measuring plate when the string hammer is in the receiving state is measured, and the measured distance is the return distance; When the return distance is too large or too small, it can be adjusted by pushing and pulling the bent support metal rod forward and backward.

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