Automatic tuning device for piano

Abstract

The utility model relates to piano tuning technical field, concretely relates to a kind of piano automatic tuning device, including control unit and executing mechanism, the executing mechanism is connected in the output end of the control unit;The control unit includes shell and the control motor and deceleration transmission assembly being arranged in the shell, the input end of the deceleration transmission assembly is connected with the output shaft of the control motor;The executing mechanism includes universal flexible shaft and tuning shaft, one end of the universal flexible shaft is located in the shell and is connected with the output end of the deceleration transmission assembly, the other end of the universal flexible shaft is located outside the shell and is detachably connected with the tuning shaft;The tuning shaft is set with tuning hole away from one end of the universal flexible shaft, the shape and size of the tuning hole are matched with the string shaft of piano.This utility model can realize high-precision tuning, flexible and convenient operation, and have good versatility and portability.

Description

Technical Field

[0001] This utility model relates to the field of piano tuning technology, specifically to an automatic piano tuning device. Background Technology

[0002] The quality of a piano's tone directly affects the artistic expression and auditory experience of a performance. Over long-term use, because the piano strings, frame, and soundboard are all elastic, when the strings are tensioned, the entire piano structure forms a comprehensive elastic system with significant internal stress. Under the impact of the hammers, the strings and this elastic system work together to produce regular vibrations, thus producing a pleasant musical tone. However, this comprehensive elastic system itself bears considerable internal stress and is susceptible to environmental factors such as changes in temperature, humidity, and air pressure. This causes the string pins to gradually undergo slight displacement or deformation, leading to changes in string tension and causing the pitch to deviate from the standard, i.e., going out of tune. At this point, the piano must be tuned to restore its pitch.

[0003] Piano tuning refers to adjusting the tension of the strings to achieve the standard pitch. It usually begins with the A note (a) in the lower octave. 1 Based on a standard of 440Hz, the piano's vibration frequency is determined using the principles of the twelve-tone equal temperament. Each note is individually calibrated according to these principles. Currently, traditional tuning methods rely on tuners manually rotating the tuning pegs with a wrench, relying on experience and repeated adjustments to achieve precise pitch adjustments. However, this method demands extremely high levels of expertise from the operator, requiring not only solid music theory knowledge but also familiarity with the piano's internal mechanical structure and tuning techniques. Furthermore, improper force application during manual tuning can easily lead to excessive or insufficient tuning, not only compromising pitch accuracy but also potentially damaging the tuning pegs and affecting the piano's lifespan. For ordinary users, the lack of professional knowledge and experience makes it difficult to independently perform tuning operations, resulting in the piano remaining out of tune for extended periods, impacting performance and practice experience.

[0004] Based on this, existing technology (invention patent application publication number CN108269553A) discloses a fully automatic piano tuning device, including a housing, a pickup module, a tuning lever module, a string pressing arm module, an LCD display screen, and a control module. The control module is connected to the pickup module and is used to receive and process the sound signal obtained by the pickup module to obtain the spectral information of the sound signal. The control module is connected to the tuning lever motor in the tuning lever module and is used to control the rotation of the tuning lever motor to drive the piano string pins to rotate via the tuning lever. The control module is connected to the LCD display screen to display the adjustment status and command prompts. In use, the above device is installed on the string pins corresponding to the keys inside the piano. A spectral curve fitting method is used to simulate the human ear system, and the adjustment peak curve is approximately matched with the standard pitch peak curve to achieve a high-quality piano tone.

[0005] However, the aforementioned existing technologies still suffer from problems such as large equipment size and poor operational flexibility in actual use. Utility Model Content

[0006] The purpose of this utility model is to provide an automatic piano tuning device that partially solves or alleviates the above-mentioned shortcomings in the prior art, enabling high-precision tuning, flexible and convenient operation, and good versatility and portability.

[0007] To solve the aforementioned technical problems, the present invention specifically adopts the following technical solution: An automatic piano tuning device includes a control unit and an actuator connected to the output of the control unit. The control unit includes a housing and a control motor and a reduction gear assembly disposed within the housing. The input of the reduction gear assembly is connected to the output shaft of the control motor. The actuator includes a universal joint and a tuning shaft. One end of the universal joint is located inside the housing and connected to the output of the reduction gear assembly. The other end of the universal joint is located outside the housing and detachably connected to the tuning shaft. A tuning hole is provided at the end of the tuning shaft away from the universal joint, and the shape and size of the tuning hole match the piano's string pins.

[0008] Preferably, as an improvement, the control unit further includes a control circuit, which is electrically connected to the control motor.

[0009] Preferably, as an improvement, the speed reduction transmission assembly includes a first transmission component and a second transmission component that are connected to each other. The first transmission component is fixedly connected to the output shaft of the control motor, and the second transmission component is rotatably connected inside the housing. One end of the universal flexible shaft located inside the housing is fixedly connected to the second transmission component.

[0010] Preferably, as an improvement, the reduction ratio of the speed reduction transmission assembly is 1:5 to 1:10.

[0011] Preferably, as an improvement, a mounting plate is provided inside the housing, and a mounting shaft is provided on the side of the second transmission member away from the universal flexible shaft. The mounting plate has a mounting hole corresponding to the position of the mounting shaft, and the mounting shaft is rotatably inserted into the mounting hole.

[0012] Preferably, as an improvement, the universal flexible shaft includes a steel wire flexible shaft and a flexible hose, the steel wire flexible shaft being rotatably inserted into the flexible hose; the two ends of the steel wire flexible shaft are respectively connected to an input connector and an output connector, the input connector being connected to the second transmission component, and the output connector being connected to the tuning shaft.

[0013] Preferably, as an improvement, the tuning shaft has a connecting hole at one end near the output connector, and the output connector is inserted into the connecting hole and fixed to the tuning shaft by means of threaded engagement or interference fit.

[0014] Preferably, as an improvement, the connecting hole and the tuning hole are not in communication; And / or, a lubricating layer is provided on the inner wall of the tuning hole.

[0015] Preferably, as an improvement, the second transmission component has two fixing blocks arranged opposite each other on the side near the input connector, and the input connector is inserted between the two fixing blocks; the input connector has bolt holes, and the fixing blocks have fixing holes at the positions corresponding to the bolt holes, and the same fastening bolt is inserted into the fixing holes and the bolt holes.

[0016] Preferably, as an improvement, the housing has a through hole, and the universal flexible shaft is inserted into the through hole; And / or, the top of the housing is open, and the top of the housing is detachably connected to a top cover, the top cover being provided with a handle; And / or, the bottom of the housing is provided with an anti-slip pad.

[0017] The beneficial technical effects of this utility model are as follows: This utility model effectively solves the technical problems of inconvenient tuning operation, large device size, and insufficient tuning accuracy in the prior art by optimizing the overall structure and transmission method, and has the following significant beneficial technical effects: 1. Improved tuning flexibility and ease of operation: This utility model adopts a split structure of "control unit + universal flexible shaft + tuning shaft". The universal flexible shaft realizes long-distance flexible power transmission, and the tuning shaft can be flexibly aligned with any string pin. There is no need to move the control unit as a whole. This can significantly improve the adaptability and ease of operation of the whole device in the small internal space of the piano, and avoid the positioning deviation and cumbersome operation caused by frequent movement of the whole device.

[0018] 2. Improved tuning accuracy and control stability: This invention incorporates a reduction gear transmission assembly within the control unit, which reduces the high-speed rotation of the control motor before transmitting it to the universal joint and tuning shaft, achieving low-speed output. A preferred reduction ratio of 1:5 to 1:10 provides precise and stable angle adjustment at the tuning end, effectively preventing overtuning caused by excessive speed, significantly improving the accuracy and convergence of pitch adjustment, and meeting the requirements for high-precision tuning.

[0019] 3. Enhanced structural reliability and connection stability: The universal flexible shaft is connected to the second transmission component of the reduction gear assembly via a double-fixed block and fastening bolt, ensuring a firm and slip-free connection during power transmission; the tuning shaft and output connector are connected by threads or interference fit, and the size matching of the tuning hole and the string pin ensures stable torque transmission during tuning, prevents disengagement or slippage, and improves operational safety.

[0020] 4. Enhanced Versatility and Adaptability: The tuning pins and universal joints are detachably connected, allowing for easy replacement of tuning pins of different specifications to meet specific tuning needs. Since different brands and models of pianos have varying shapes and sizes of their string pins, configuring multiple tuning pins to match different string pins enables multi-purpose functionality, significantly enhancing the device's compatibility and applicability, meeting diverse piano tuning requirements, and reducing users' equipment procurement and maintenance costs.

[0021] 5. Optimized Device Integration and User Experience: The control unit integrates the control motor, reduction gear transmission components, and control circuitry into a single housing, resulting in a compact structure and small size. A detachable top cover with a handle facilitates daily carrying, on-site deployment, and internal maintenance. Anti-slip pads on the bottom of the housing not only enhance the stability of the device during operation and prevent slippage but also effectively isolate vibrations that may be generated during motor operation, preventing these vibrations from being transmitted to the piano body through the support surface. This reduces interference with the piano structure and protects the stability and tuning accuracy of the piano's acoustic system. This invention's overall structure balances functionality, safety, and portability, making it suitable for various usage scenarios, including home use, educational institutions, and professional performances, significantly enhancing the user experience.

[0022] 6. Extend service life and reduce mechanical damage: The inner wall of the tuning hole is equipped with a lubricating layer, which can reduce friction and wear between the tuning pin and the string pin, and avoid damage to the string pin or poor tuning due to dryness and jamming; at the same time, the split structure can avoid interference with other internal components of the piano and reduce operational risks. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. The elements or parts in the drawings are not necessarily drawn to scale. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0024] Figure 1 A three-dimensional structural schematic diagram provided for an embodiment of this utility model; Figure 2 for Figure 1 The front view; Figure 3 for Figure 1 The left view; Figure 4 for Figure 1 Top view; Figure 5 for Figure 1 A schematic diagram of the structure after removing the outer shell; Figure 6 for Figure 5 Left view of the intermediate and secondary gears and actuator; Figure 7 for Figure 5 A schematic diagram of the structure of the actuator; Figure 8 for Figure 7 Rear view; Figure 9 This is a three-dimensional structural diagram of the connection between the present invention and a piano.

[0025] Summary of reference numerals in the attached diagram: 1. Control unit; 11. Housing; 12. Control circuit; 13. Control motor; 14. Reduction transmission assembly; 141. First-stage gear; 142. Second-stage gear; 15. Mounting plate; 16. Mounting shaft; 17. Through hole; 18. Fixing block; 19. Fastening bolt; 2. Actuator; 21. Universal flexible shaft; 22. Tuning shaft; 23. Input connector; 24. Output connector; 25. Tuning hole; 3. Piano body; 31. String pins. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0027] In this document, suffixes such as "module," "part," or "unit" used to denote elements are used only for the purpose of illustrative purposes and have no specific meaning in themselves. Therefore, "module," "part," or "unit" can be used interchangeably.

[0028] In this document, the terms "upper," "lower," "inner," "outer," "front," "rear," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In this document, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0030] In this document, "and / or" includes any and all combinations of one or more of the listed related items.

[0031] In this article, "multiple" means two or more, that is, it includes two, three, four, five, etc.

[0032] As used in this specification, the term "about" typically means + / -5% of the value, more typically + / -4% of the value, more typically + / -3% of the value, more typically + / -2% of the value, even more typically + / -1% of the value, and even more typically + / -0.5% of the value.

[0033] In this specification, certain embodiments may be disclosed in a range-bound format. It should be understood that this "range-bound" description is merely for convenience and brevity and should not be construed as a rigid limitation on the disclosed range. Therefore, the description of a range should be considered as having specifically disclosed all possible subranges and the individual numerical values ​​within those ranges. For example, a description of the range 1-6 should be considered as having specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and the individual numbers within those ranges, such as 1, 2, 3, 4, 5, and 6. This rule applies regardless of the breadth of the range.

[0034] The applicant notes that existing piano tuning devices often suffer from drawbacks such as poor operational flexibility, insufficient portability and adaptability, and inadequate tuning accuracy, as detailed below: 1) The tuning lever module is inconvenient to position and lacks operational flexibility. One end of the tuning lever is fixed to the shaft of the tuning lever motor, while the other end is free. In use, the free end of the tuning lever is installed on the corresponding string pin of the piano. The tuning lever motor drives the tuning lever to rotate the string pin, thus adjusting the string tension. Because the tuning lever is rigidly connected to the tuning lever motor, each time a string pin is changed for tuning, the entire device must be moved to the corresponding position of the target string pin, and the stability and centering accuracy of the device must be maintained during the adjustment process. This design not only makes the operation process cumbersome and time-consuming, but also makes it difficult to achieve quick and accurate alignment in the confined space inside a piano.

[0035] 2) Complex structure and low integration result in a large size and insufficient portability and adaptability. The integration of multiple functional units and numerous components leads to a large size and heavy weight. This not only limits its installation and use in different piano models (especially compact upright pianos), but also increases the difficulty of transportation, storage, and on-site deployment.

[0036] 3) The direct connection between the tuning lever and the tuning lever motor shaft results in insufficient tuning precision, affecting tuning accuracy. Therefore, this invention proposes an automatic piano tuning device to partially solve or alleviate the above-mentioned shortcomings in the prior art.

[0037] Example 1: An automatic piano tuning device, such as Figures 1 to 9 As shown, it includes a control unit 1 and an actuator 2. The actuator 2 is connected to the output end of the control unit 1 and is used to realize remote and precise adjustment of the string pin 31.

[0038] like Figures 1 to 4As shown, the control unit 1 includes a housing 11, a control circuit 12, a control motor 13, and a reduction gear transmission assembly 14. The housing 11 serves as the main structural support, with internal mounting space. The control circuit 12, control motor 13, and reduction gear transmission assembly 14 are all installed within the housing 11. The control circuit 12 and control motor 13 are fixedly connected to the housing 11 by bolts, and the control circuit 12 is electrically connected to the control motor 13. The control circuit 12 receives external input signals (such as via buttons, Bluetooth, or an audio feedback system) and controls the start / stop, rotation direction, and speed of the motor 13 according to preset logic, thereby achieving automatic adjustment of the piano's pitch. The output shaft of the control motor 13 serves as the power source, driving the entire tuning process. The reduction gear transmission assembly 14 is located on the output path of the control motor 13, with its input end connected to the output shaft of the control motor 13. It converts the high-speed rotation of the motor into a low-speed, high-torque output, thus achieving fine tuning.

[0039] The reduction transmission assembly 14 includes a first transmission component and a second transmission component that are connected to each other. In this embodiment, the reduction transmission assembly 14 adopts a reduction gear set, with the first transmission component being a primary gear 141 and the second transmission component being a secondary gear 142, which mesh with each other. The primary gear 141 is coaxially fixedly connected to the output shaft of the control motor 13, and the secondary gear 142 is rotatably connected inside the housing 11. Specifically, a mounting plate 15 is fixedly connected inside the housing 11, and the mounting plate 15 is arranged parallel to the secondary gear 142. A mounting shaft 16 is vertically fixedly connected to the side of the secondary gear 142 near the mounting plate 15. The mounting plate 15 has a mounting hole corresponding to the position of the mounting shaft 16, and the mounting shaft 16 is rotatably inserted into the mounting hole to achieve stable support for the secondary gear 142.

[0040] The reduction ratio of the reduction gear assembly 14 is 1:5 to 1:10, which can effectively reduce the output speed while ensuring sufficient output torque, meeting the dual requirements of precision and stability for piano tuning. Specifically, the reduction ratio of the reduction gear assembly 14 can be 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, etc.

[0041] In this embodiment, a speed-limiting adjustment mechanism is provided to meet the need for fine adjustment of string tension during piano tuning. This mechanism allows for slow and precise adjustment when small-angle or even micro-angle rotation is required near the target pitch. It also avoids the problem of "over-tuning" or "under-tuning" caused by excessively fast rotation speed, thereby improving the accuracy of pitch convergence.

[0042] Furthermore, this speed-limiting adjustment mechanism can, to some extent, avoid or mitigate the risk of string breakage or damage to the tuning pegs caused by excessive instantaneous torque.

[0043] like Figures 5 to 8As shown, the actuator 2 includes a universal flexible shaft 21 and a tuning shaft 22. One end of the universal flexible shaft 21 is located inside the housing 11 and is connected to the output end (i.e., the secondary gear 142) of the reduction gear assembly 14; the other end of the universal flexible shaft 21 extends outside the housing 11 and is detachably connected to the tuning shaft 22. Specifically, the universal flexible shaft 21 includes a steel wire flexible shaft and a flexible hose wrapped around it. The steel wire flexible shaft can rotate freely inside the flexible hose, realizing flexible power transmission.

[0044] In some embodiments, a through hole 17 is provided on the side wall of the housing 11, and the universal flexible shaft 21 is inserted into the through hole 17.

[0045] The flexible steel wire shaft has an input connector 23 and an output connector 24 connected to its two ends, respectively. Both the input connector 23 and the output connector 24 are coaxially and fixedly connected to the flexible steel wire shaft. The input connector 23 is connected to the secondary gear 142 via a fixed structure. Specifically, two opposing fixing blocks 18 are fixedly connected to the side of the secondary gear 142 near the input connector 23, and the input connector 23 is inserted between the two fixing blocks 18. The input connector 23 has bolt holes, and the fixing blocks 18 have fixing holes at the corresponding positions of the bolt holes. After the bolt holes and fixing holes are aligned, the same fastening bolt 19 is inserted into both the bolt holes and fixing holes to ensure a firm connection without slippage.

[0046] The tuning shaft 22 is a replaceable module. A connection hole is provided at the end of the tuning shaft 22 closest to the output connector 24. The output connector 24 is inserted into the connection hole and fixedly connected via a threaded or interference fit, facilitating quick assembly and disassembly. A tuning hole 25 is provided at the end of the tuning shaft 22 furthest from the universal joint 21. The shape and size of the tuning hole 25 match the shape and size of the piano's string pins 31, for example, it can be hexagonal, square, or other common string pin shapes, ensuring that the string pins 31 rotate with the tuning shaft 22 during tuning, achieving reliable power transmission.

[0047] In some embodiments, the connecting hole and the tuning hole 25 are not connected to each other, so as to prevent the output connector 24 from penetrating into the tuning hole 25 through the connecting hole and coming into contact with or even colliding with the string pin 31, thereby preventing the string pin 31 from being scratched or damaged and ensuring the service life of the string pin 31.

[0048] In some embodiments, the inner wall of the tuning hole 25 is coated with a lubricating layer, such as a Teflon coating or a solid lubricant, to reduce frictional wear between the inner wall of the tuning hole 25 and the string pin 31, prevent jamming during tuning, and further avoid damage to the string pin 31.

[0049] In some embodiments, the top of the housing 11 is an open structure, and a top cover is detachably connected to the top of the housing 11. The top of the housing 11 is closed by the top cover, which facilitates the opening of the top cover to maintain the internal structure, and also protects the internal structure of the housing 11. A handle is fixedly connected to the top of the top cover for easy carrying of the entire device.

[0050] In some embodiments, an anti-slip pad is fixedly connected to the bottom of the housing 11, which can increase the friction between the bottom of the housing 11 and the support surface, prevent the device from sliding relative to the support surface during operation, and effectively isolate the vibration generated by the control motor 13 during operation from being transmitted to the piano body 3, thus avoiding disturbance to the piano structure.

[0051] The working principle of an automatic piano tuning device is as follows: When using, such as Figure 9 As shown, the control unit 1 is placed on the piano body 3, and the output end of the actuator 2 (i.e., the tuning shaft 22) is connected to the corresponding string shaft 31.

[0052] According to the specifications of the piano's string pins 31, select a matching tuning pin 22 and install it onto the output end of the universal joint 21; fit the tuning hole 25 of the tuning pin 22 onto the target string pin 31; after starting the device, the control circuit 12 drives the control motor 13 to run, and the power is reduced in speed and increased in torque by the reduction transmission component 14, and then transmitted to the tuning pin 22 through the universal joint 21, causing the string pin 31 to rotate slowly, so as to achieve precise adjustment of the string tension until the target pitch is reached.

[0053] Example 2: An automatic piano tuning device, which differs from Embodiment 1 in that the control circuit 12 includes a central controller, a motor drive module, a signal acquisition module, and a human-computer interaction interface.

[0054] The central controller uses a microcontroller (MCU), such as an STM32F103C8T6 or ESP32 chip, to run the control program, receive pitch detection signals or user operation commands, perform data processing and logical judgments, and output control signals to the motor drive module.

[0055] The motor drive module uses an H-bridge drive circuit (such as an integrated chip L298N or DRV8833) and is connected between the central controller and the control motor 13. It responds to the PWM signal and direction signal output by the controller to drive the control motor 13 to rotate forward, reverse or stop, and adjust its speed, thereby driving the tuning shaft 22 to rotate precisely through the reduction transmission component 14 and the universal flexible shaft 21.

[0056] The signal acquisition module is used to acquire the pitch information of the current string. In a preferred embodiment, the module includes a high-sensitivity microphone (such as a MEMS microphone SPH0641LU4H) for acquiring the sound signal emitted by the string; the central controller samples the received audio signal and extracts the fundamental frequency through a Fast Fourier Transform (FFT) algorithm, and calculates the deviation between the current pitch and the target pitch (such as a¹=440Hz).

[0057] The human-computer interaction interface includes a button module and a display module (such as an LCD screen or LED indicator), which are set on the surface of the housing. They are used to receive user operations such as starting tuning, selecting a tone zone, or viewing the tuning status, and to display the current pitch, deviation value, and tuning progress in real time.

[0058] During operation, after the user starts the tuning program, the control circuit 12 drives the control motor 13 to rotate slowly, which in turn drives the tuning shaft 22 to adjust the string tension. At the same time, the microphone periodically collects the string pitch, and the central controller compares the difference between the actual pitch and the target pitch in real time: if the pitch is too low, the control motor 13 makes a slight adjustment in the positive direction; if the pitch is too high, it makes a slight adjustment in the negative direction. When the pitch deviation is less than the preset threshold (such as ±0.5 cents), the controller sends a stop signal to complete the tuning of that note.

[0059] Through the structural configuration of this embodiment, the control circuit 12 can realize closed-loop automatic tuning without relying on manual listening and judgment, significantly reducing the operation threshold and improving tuning accuracy and automation.

[0060] Example 3: An automatic piano tuning device, which differs from Embodiment 2 in that the control circuit 12 further includes a communication module (such as a Bluetooth module HC-05 or a Wi-Fi module ESP-01S), which supports wireless connection with external terminal devices (such as smartphones or tablets) to realize remote control, parameter setting or tuning data recording.

[0061] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0062] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this utility model, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a computer terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this utility model.

[0063] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. An automatic piano tuning device, characterized in that, The instrument includes a control unit (1) and an actuator (2), the actuator (2) being connected to the output end of the control unit (1); the control unit (1) includes a housing (11) and a control motor (13) and a speed reduction transmission assembly (14) disposed within the housing (11), the input end of the speed reduction transmission assembly (14) being connected to the output shaft of the control motor (13); the actuator (2) includes a universal joint (21) and a tuning shaft (22), one end of the universal joint (21) being located inside the housing (11) and connected to the output end of the speed reduction transmission assembly (14), the other end of the universal joint (21) being located outside the housing (11) and detachably connected to the tuning shaft (22); the tuning shaft (22) having a tuning hole (25) at the end away from the universal joint (21), the shape and size of the tuning hole (25) being matched with the string pins (31) of the piano.

2. The automatic piano tuning device according to claim 1, characterized in that, The control unit (1) further includes a control circuit (12), which is electrically connected to the control motor (13).

3. The automatic piano tuning device according to claim 1 or 2, characterized in that, The speed reduction transmission assembly (14) includes a first transmission component and a second transmission component that are connected to each other. The first transmission component is fixedly connected to the output shaft of the control motor (13), and the second transmission component is rotatably connected inside the housing (11). One end of the universal flexible shaft (21) located inside the housing (11) is fixedly connected to the second transmission component.

4. The automatic piano tuning device according to claim 3, characterized in that, The reduction ratio of the speed reduction transmission assembly (14) is 1:5 to 1:

10.

5. The automatic piano tuning device according to claim 3, characterized in that, An installation plate (15) is provided inside the housing (11). An installation shaft (16) is provided on the side of the second transmission component away from the universal flexible shaft (21). An installation hole is provided on the installation plate (15) corresponding to the position of the installation shaft (16). The installation shaft (16) is rotatably inserted into the installation hole.

6. The automatic piano tuning device according to claim 3, characterized in that, The universal flexible shaft (21) includes a steel wire flexible shaft and a hose, the steel wire flexible shaft being rotatably inserted into the hose; the two ends of the steel wire flexible shaft are respectively connected to an input connector (23) and an output connector (24), the input connector (23) being connected to the second transmission component, and the output connector (24) being connected to the tuning shaft (22).

7. The automatic piano tuning device according to claim 6, characterized in that, The tuning shaft (22) has a connection hole at one end near the output connector (24), and the output connector (24) is inserted into the connection hole and fixed to the tuning shaft (22) by means of threaded fit or interference fit.

8. The automatic piano tuning device according to claim 7, characterized in that, The connecting hole is not connected to the tuning hole (25); And / or, a lubricating layer is provided on the inner wall of the tuning hole (25).

9. The automatic piano tuning device according to claim 6, characterized in that, The second transmission component has two fixing blocks (18) arranged opposite each other on the side near the input connector (23), and the input connector (23) is inserted between the two fixing blocks (18); the input connector (23) has bolt holes, and the fixing blocks (18) have fixing holes at the positions corresponding to the bolt holes, and the same fastening bolt (19) is inserted into the fixing holes and the bolt holes.

10. An automatic piano tuning device according to any one of claims 5-9, characterized in that, The housing (11) has a through hole (17), and the universal flexible shaft (21) is inserted into the through hole (17); And / or, the top of the housing (11) is open, and the top of the housing (11) is detachably connected to a top cover, the top cover being provided with a handle; And / or, the bottom of the housing (11) is provided with an anti-slip pad.

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