micrometer piano key planer

Abstract

The utility model discloses a micrometer piano key flatness instrument, and the utility model relates to piano manufacturing and maintenance technical field, including instrument support subassembly and high limit crossbeam subassembly, the instrument support subassembly includes micrometer instrument, ranging probe, slide rail, sliding block, eye -shaped connecting piece, lifting platform, bottom foot slide rail, bottom foot sliding block, lock foot knob, lifting sliding block, lifting swallow tail guide rail, fine adjustment knob and lock button. Modular structure provides the flexible adjustment ability of multidimension, makes ranging probe to be positioned to the any measuring point of piano key quickly, and high limit crossbeam can provide unified, accurate mechanical limit for piano key lifting. The instrument effectively reduces the operation threshold and the dependence on skilled workers, and the measurement data is accurate and reliable, and the efficiency and consistency of the work of replacing the felt ring and the paper ring are improved significantly, which helps to ensure the final tuning and repairing quality of the piano keyboard.

Description

Technical Field

[0001] This utility model relates to the field of piano manufacturing and repair technology, specifically a micrometer piano key level. Background Technology

[0002] The piano is a classic keyboard instrument. Its sound production relies on a complex lever system (action mechanism) that drives hammers to strike the strings when the player presses a key. As the most direct interface between the player and the piano, the keyboard requires precise consistency in the height of each key and the depth of its depressed position (key depth), along with a reasonable travel distance. Any slight unevenness can lead to an imbalance in touch, inconsistent volume, and even affect the proper functioning of the action mechanism, severely damaging the instrument's performance and musical quality.

[0003] During long-term use or maintenance of a piano, the felt and paper rings beneath the keys, which serve as cushions and positioning elements, will deform due to wear and aging, causing changes in key height and depth. Especially with wooden keys, long-term thermal expansion and contraction, as well as environmental changes, can lead to imperceptible twisting and concavity, and even sinking of the keypad (waist collapse). While these are natural phenomena in pianos, the leverage effect of the keys amplifies these errors. Therefore, almost every key has a unique shape, and the standardized, batch-installed paper rings at the factory are no longer possible. Thus, replacing the entire keypad or only a portion of it requires specific measurements of each key.

[0004] Traditional key leveling methods rely heavily on the experience and feel of the technician: technicians typically use basic gauges or rulers for measurement, and roughly level the keys by repeatedly trying and adding or removing paper rings of different thicknesses. This method has several significant technical drawbacks: First, its measurement accuracy is limited, making it difficult to quantify micron-level differences in paper ring thickness; second, the entire process is inefficient, requiring repeated disassembly and reassembly of the keys for comparison, making the work tedious; finally, the consistency of the adjustment results is difficult to guarantee, as adjustments made by different technicians or at different times may result in deviations.

[0005] To address the aforementioned issues, a specialized tool was designed that can quickly, accurately, and quantitatively measure the height and depth data of all piano keys and guide maintenance personnel in accurately selecting the appropriate washer thickness, thereby resolving the technical problems mentioned above. Utility Model Content

[0006] In view of the shortcomings of the prior art, this utility model provides a micrometer piano key level instrument, which solves the technical problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a micrometer piano key level, comprising an instrument support assembly and a height-limiting beam assembly. The instrument support assembly includes a micrometer, a distance measuring probe, a slide rail, a slider, an eye-shaped connecting piece, a lifting platform, a base slide rail, a base slider, a locking knob, a lifting slider, a lifting dovetail guide rail, a fine-tuning knob, and a locking knob. Two lifting platforms are provided, each mounted on a pair of base slide rails via a base slider and a locking knob. Each lifting platform is equipped with a lifting slider, which is connected to the lifting dovetail guide rail via a fine-tuning knob and a locking knob to enable movement and limiting of the lifting slider along the lifting dovetail guide rail. The slide rail is connected to a pair of lifting sliders via a pair of eye-shaped connecting pieces, and the height-limiting beam is connected to another pair of lifting sliders via another pair of eye-shaped connecting pieces. The slider is slidably mounted on the slide rail, the micrometer is mounted on the slider, and the distance measuring probe is mounted at the lower end of the micrometer.

[0008] Preferably, the micrometer has a measuring range of 0-24.5 mm, a resolution of 0.001 mm, and a zeroing function.

[0009] Preferably, the slide rail is a carbon steel slide rail, the slider is a ball block slider, and the slider is engaged with the slide rail, so that the micrometer can slide horizontally steplessly.

[0010] Preferably, the eye-shaped connecting piece has an elongated hole for adjusting the width of the instrument bracket assembly and the height-limiting beam assembly to fit the piano keyboard.

[0011] Preferably, the base slide rail is configured to be fixed to the repair bed by self-tapping screws or wood clamps.

[0012] Preferably, the minimum adjustment distance of the fine-tuning knob is 0.1 mm.

[0013] Preferably, the height-limiting crossbeam is made of aluminum alloy with a straightness error of 0.1%.

[0014] Preferably, the instrument bracket assembly and the height limiting beam assembly share the same lifting platform, base slider, and base rail structure for independent adjustment and positioning.

[0015] Beneficial effects This invention provides a micrometer piano key leveling instrument. Through the combination of a precisely positionable instrument support assembly and an independently adjustable height-limiting beam assembly, it transforms the traditional experience-dependent piano key leveling process into an objective and quantifiable measurement process. Its modular structure provides multi-dimensional flexible adjustment capabilities, allowing the ranging probe to quickly position itself to any point on the key to be measured, while the height-limiting beam provides a uniform and precise mechanical limit for key lifting. This instrument effectively lowers the operational threshold and reduces reliance on skilled workers. The measurement data is accurate and reliable, significantly improving the efficiency and consistency of changing felt and paper rings, and helping to ensure the final quality of piano keyboard adjustment. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the micrometer piano key level instrument described in this utility model.

[0017] In the diagram: 1. Micrometer; 2. Distance measuring probe; 3. Slide rail; 4. Slider; 5. Eyepiece connecting piece; 6. Lifting platform; 7. Base slide rail; 8. Base slider; 9. Locking knob; 10. Lifting slider; 11. Lifting dovetail guide rail; 12. Fine adjustment knob; 13. Locking button; 14. Height limiting beam. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Please see Figure 1This utility model provides a technical solution: a micrometer piano key level, including an instrument support assembly and a height limiting beam assembly. The instrument support assembly includes a micrometer instrument 1, a distance measuring probe 2, a slide rail 3, a slider 4, an eyepiece connecting piece 5, a lifting platform 6, a base slide rail 7, a base slider 8, a locking knob 9, a lifting slider 10, a lifting dovetail guide rail 11, a fine adjustment knob 12, and a locking knob 13. There are two lifting platforms 6, each mounted on a pair of base slide rails 7 via a base slider 8 and a locking knob 9. Each lifting platform 6 is equipped with... A lifting slider 10 is provided, which is connected to a lifting dovetail guide rail 11 via a fine-tuning knob 12 and a locking knob 13 to enable the lifting slider 10 to move and be limited along the lifting dovetail guide rail 11; the slide rail 3 is connected to a pair of lifting sliders 10 via a pair of eye-shaped connecting pieces 5, and the height limiting beam 14 is connected to another pair of lifting sliders 10 via another pair of eye-shaped connecting pieces 5; the slider 4 is slidably mounted on the slide rail 3, the micrometer instrument 1 is mounted on the slider 4, and the distance measuring probe 2 is mounted on the lower end of the micrometer instrument 1.

[0020] In this embodiment, the micrometer instrument 1 is further configured to have a measuring range of 0-24.5mm, a resolution of 0.001mm, and a zeroing function.

[0021] In this embodiment, the slide rail 3 is a carbon steel slide rail, the slider 4 is a ball slider, and the slider 4 is fitted with the slide rail 3 so that the micrometer instrument 1 can slide horizontally steplessly.

[0022] In this embodiment, the eye-shaped connecting piece 5 is provided with an elongated hole for adjusting the width of the instrument bracket assembly and the height-limiting beam assembly to fit the piano keyboard.

[0023] In this embodiment, the base slide rail 7 is configured to be fixed to the repair bed by self-tapping screws or wood clamps.

[0024] In this embodiment, the minimum adjustment distance of the fine-tuning knob 12 is further set to 0.1 mm.

[0025] In this embodiment, the height-limiting beam 14 is made of aluminum alloy with a straightness error of 0.1%.

[0026] In this embodiment, the instrument bracket assembly and the height limiting beam assembly share the same lifting platform 6, base slider 8, and base slide rail 7 structure for independent adjustment and positioning.

[0027] Its detailed connection method is a well-known technology in this field. The following mainly introduces the working principle and process, and the specific work is as follows.

[0028] Example: The mounting base of the instrument is a pair of parallel foot rails 7, which can be firmly fixed to the repair bed of the simulated piano center plate by self-tapping screws or wood clamps. Here, each foot rail 7 is equipped with a foot slider 8 that can slide along its length. Each foot slider 8 is equipped with a locking knob 9 for locking it to the foot rail 7 at any position. A lifting platform 6 is fixedly installed on the top of each foot slider 8. The lifting platform 6 is the core component of vertical movement. Its main body is a lifting dovetail guide rail 11. A lifting slider 10 can move up and down along this lifting dovetail guide rail 11. This precision movement is driven by a fine-tuning knob 12. This knob can achieve a minimum fine adjustment of 0.1mm through a precision thread. Once the height is adjusted to the target position, the lifting slider 10 can be firmly locked to the lifting dovetail guide rail 11 by tightening the locking knob 13.

[0029] The two main functional components of this instrument—the instrument support assembly and the height-limiting beam assembly—are built on this lifting system. The core of the instrument support assembly is a carbon steel slide rail 3 with a straightness error ≤0.1%. Both ends of the slide rail 3 are connected to a pair of lifting sliders 10 via a pair of eye-shaped connecting pieces 5. The elongated hole design on the eye-shaped connecting pieces 5 allows for adaptive fine-tuning of the slide rail 3's lateral installation position even when the base slide rail 7 is fixed, to match keyboards of different widths. A stepless sliding slider 4, preferably a ball-bearing slider, is fitted onto this slide rail 3. The micrometer instrument 1 is mounted on this slider 4, with its lower measuring probe 2 contacting the keyboard surface. This micrometer instrument 1 has a measuring range of 0-24.5mm, a resolution of 0.001mm, and a zeroing function, perfectly meeting the needs of paper ring fine-tuning.

[0030] The core of the height-limiting beam assembly is an aluminum alloy height-limiting beam 14 with a straightness error of ≤0.1%. The two ends of the beam are connected to another pair of lifting sliders 10 through another pair of eye-shaped connecting pieces 5. The width is finely adjusted by using the elongated holes of the eye-shaped connecting pieces 5.

[0031] Instrument stand positioning: When measuring the height of the black and white keys, the operator first inserts the keys of the removed action back into the keyboard (the new felt rings have already been installed), and then positions the instrument stand: slide the base slider 8 that supports the instrument stand assembly so that the distance measuring probe 2 is accurately positioned at the center line of the black and white key pin holes, and lock the locking knob 9; then fine-tune the fine-tuning knobs 12 of the lifting sliders at both ends so that the distance measuring probe 2 gently touches the surface of the keys, and then lock the locking knob 13.

[0032] Next, the height-limiting beam is positioned: based on the target key height, for example, 67mm for the white keys, the lifting slider 10 supporting the height-limiting beam assembly is finely adjusted to ensure the height of both ends of the height-limiting beam 14 is accurate to 67mm and locked; then, the bottom slider 8 on that side is slid so that the beam is just suspended directly above the end of the white key and locked. When measuring the white key height, a grand piano finger-pressing key flattening aid is used to press down on the end of a key in one tone range to simulate the pressure transmission effect of the action mechanism. Then, the distance probe 2 of the micrometer instrument 1 is moved sequentially to the center line position of the round pin hole of each white key through the sliding slider 4. After zeroing the instrument, the end of the white key is gently lifted with a finger and moved up to touch the lower beam of the height-limiting beam 14. The reading displayed on the instrument at this time is the paper ring compensation thickness required for the key to reach the standard height. This data is recorded on the record sheet on the material preparation rack; after completing one tone range, the aid is moved to the next tone range and its pressure is finely adjusted. The above process is repeated until all 52 white keys have been measured.

[0033] For measuring the height of the black keys, adjust the height of the height limiting beam 14 to the standard height of the black key, such as 78mm, and slide the bottom slider 8 to suspend it above the end of the black key. Then, pinch the middle of the black key with your fingers until the end touches the beam. Read and record the data using the instrument. Repeat the above process until all 36 black keys have been measured.

[0034] At this point, the height measurement of all 88 piano keys is complete.

[0035] For key depth measurement, the principle is the same for white and black keys: Keep the measuring probe 2 of the instrument stand lightly touching the key surface 25mm from the key end. Then adjust the height limiting beam 14 to the calculated key depth height, for example, 56mm for white keys. Finally, press the key's locking head to move the key end to touch the beam. The instrument reading at this point reflects the key depth data, used to guide the adjustment of the paper rings at the flat pins of the 52 white keys. The same procedure applies to the 36 black keys.

[0036] At this point, the key depth measurements for all 88 piano keys have been completed.

[0037] After all measurements are recorded, new paper rings of appropriate thickness are selected and inserted for each key's round or flat pin according to the record sheet, completing the initial replacement. Finally, a key level is used for fine-tuning to ensure the entire keyboard's flatness and touch are at their best. Thus, this micrometer piano key level gauge completes the replacement and precision adjustment of the old piano keyboard's felt paper rings.

[0038] It should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

Claims

1. A micrometer piano key level, characterized in that, Includes instrument bracket assembly and height-limiting beam assembly: The instrument bracket assembly includes a micrometer (1), a distance measuring probe (2), a slide rail (3), a slider (4), a picture-shaped connecting piece (5), a lifting platform (6), a base slide rail (7), a base slider (8), a locking knob (9), a lifting slider (10), a lifting dovetail guide rail (11), a fine adjustment knob (12), and a locking knob (13). There are two lifting platforms (6), each of which is mounted on a pair of base slide rails (7) via base sliders (8) and locking knobs (9); Each lifting platform (6) is equipped with a lifting slider (10), which is connected to the lifting dovetail guide rail (11) via a fine-tuning knob (12) and a locking knob (13) to enable the lifting slider (10) to move and be limited along the lifting dovetail guide rail (11); The slide rail (3) is connected to a pair of lifting sliders (10) through a pair of eye-shaped connecting pieces (5), and the height limiting beam (14) is connected to another pair of lifting sliders (10) through another pair of eye-shaped connecting pieces (5); The slider (4) is slidably mounted on the slide rail (3), the micrometer instrument (1) is mounted on the slider (4), and the distance measuring probe (2) is mounted on the lower end of the micrometer instrument (1).

2. The micrometer piano key leveling instrument according to claim 1, characterized in that... The micrometer instrument (1) has a measuring range of 0-24.5mm, a resolution of 0.001mm, and a zeroing function.

3. The micrometer piano key level instrument according to claim 1, characterized in that... The slide rail (3) is a carbon steel slide rail, and the slider (4) is a ball slider. The slider (4) is fitted with the slide rail (3) so that the micrometer instrument (1) can slide horizontally steplessly.

4. The micrometer piano key leveling instrument according to claim 1, characterized in that... The eye-shaped connecting piece (5) is provided with an elongated hole for adjusting the width of the instrument bracket assembly and the height limiting beam assembly to fit the piano keyboard.

5. The micrometer piano key leveling instrument according to claim 1, characterized in that... The base slide rail (7) is configured to be fixed to the repair bed by self-tapping screws or wood clamps.

6. The micrometer piano key level according to claim 1, characterized in that... The minimum adjustment distance of the fine adjustment knob (12) is 0.1 mm.

7. The micrometer piano key leveling instrument according to claim 1, characterized in that... The height-limiting crossbeam (14) is made of aluminum alloy and has a straightness error of 0.1%.

8. The micrometer piano key level instrument according to claim 1, characterized in that... The instrument bracket assembly and the height limiting beam assembly share the same lifting platform (6), base slider (8) and base rail (7) structure for independent adjustment and positioning.

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