Automatic tuning structure for a guitar
Patent Information
- Application Number
- CN202521987535.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-16
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2035-09-16
AI Technical Summary
但该方式存在显著缺陷：其一，操作效率低，尤其在现场演奏场景中，手动转调需消耗较长时间，易中断演奏连贯性；其二，调节精度依赖经验，新手或非专业演奏者难以精准控制弦轴转动角度，易导致音高偏差（误差常超过5音分），影响演奏效果；其三，稳定性差，手动调节后弦轴易因振动出现回松，导致音高漂移
本实用新型通过驱动装置对琴弦的拉力进行调节，调节过程中，安装片上半包围状贯穿槽围合形成的安装部，会随琴弦拉力变化带动形变区产生微小形变，贴附于形变区的应变片可将形变转化为对应信号，实时反馈琴弦当前拉力；驱动装置则穿过安装部的贯穿孔，通过活动连接组件带动弦轴绕安装座转动，精准改变琴弦缠绕长度以调节拉力。相对于人工调节吉他的音高，该结构无需演奏者凭经验试音或控制弦轴转动角度，彻底摆脱对经验的依赖；同时，驱动装置可定量调节弦轴转动，避免人工操作时的用力不均，解决手动调节效率低、精度差、稳定性不足的问题。
Smart Images
Figure CN224907568U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of string instrument tuning technology, and in particular to an automatic modulation structure for guitar. Background Technology
[0002] As a stringed instrument, the guitar's performance is directly related to the pitch corresponding to the string tension. "Modification" is a core requirement in guitar playing—whether playing musical works in different keys (such as changing from C major to G major) or adapting to the pitch coordination of a band ensemble, pitch changes must be achieved by adjusting the string tension. Traditional guitar modulation relies on manual operation of the tuning pegs: the player needs to use a tuning wrench or directly turn the tuning pegs at the headstock to adjust the tension by changing the length of the string winding, thus changing the pitch. However, this method has significant drawbacks: First, it is inefficient, especially in live performances, as manual modulation takes a long time and can easily interrupt the flow of the performance; second, the adjustment precision depends on experience, and beginners or non-professional players find it difficult to accurately control the angle of the tuning pegs, which can easily lead to pitch deviations (often exceeding 5 cents), affecting the performance; third, it has poor stability, as the tuning pegs can easily loosen due to vibration after manual adjustment, causing pitch drift.
[0003] Based on this, the present invention provides an automatic transposition structure for guitars to solve the above problems. Utility Model Content
[0004] This utility model provides an automatic tuning structure for a guitar, including a headstock with a mounting bracket inside. A mounting plate is fixedly mounted on the mounting bracket, and the mounting plate has a mounting portion for mounting a tuning pin. The mounting portion is surrounded by a semi-enclosed through groove formed on the mounting plate. A deformation zone is formed at the junction of the mounting portion and the mounting plate, and a strain gauge is attached to the deformation zone. A mounting base is fixedly provided at the end of the mounting portion away from the deformation zone. The tuning pin is rotatably mounted on the mounting base, and its axis is perpendicular to the mounting plate. A driving device is also provided on the mounting bracket. The power output shaft of the driving device is coaxially arranged with the tuning pin. A through hole is provided on the mounting portion corresponding to the power output shaft. The power output shaft passes through the through hole and is driven to the tuning pin through a movable connecting assembly to drive the tuning pin to rotate.
[0005] Furthermore, the movable connection assembly includes a connecting rod fixedly disposed at the top end of the power output shaft, the connecting rod being disposed perpendicular to the power output shaft; the movable connection assembly also includes a limiting groove formed at the bottom end of the tuning shaft, the connecting rod being located within the limiting groove, for driving the tuning shaft to rotate around its own axis by pushing the limiting groove.
[0006] Furthermore, the mounting base has a vertical through-hole, which is connected to the through-hole; the chord shaft is rotatably inserted into the mounting hole, and an annular groove is formed on the inner side wall of the mounting hole. A protruding ring is formed on the outer side wall of the chord shaft corresponding to the annular groove, and the protruding ring is slidably embedded in the annular groove.
[0007] Furthermore, the driving device includes a drive motor fixedly mounted on the mounting bracket and a reducer drivenly connected to the drive motor, wherein the power output shaft is the output shaft of the reducer.
[0008] Furthermore, the headstock also includes a shell with an opening at the top, and a cover plate is detachably provided at the opening of the shell; the mounting bracket is located inside the shell, and the cover plate has a receiving hole corresponding to the mounting seat, and the mounting seat and the tuning pegs on it extend through the receiving hole to the outside of the shell.
[0009] Furthermore, the portion of the tuning pin located on the outside of the mounting base has a connecting hole, which extends through the tuning pin along a direction perpendicular to its axis.
[0010] Furthermore, a PCB board is fixedly mounted on the mounting bracket. The PCB board integrates a DSP, a Bluetooth module, and an ADC module. The DSP is connected to the strain gauge through the ADC module.
[0011] Furthermore, the PCB board also integrates a Bluetooth module.
[0012] Furthermore, it also includes a microphone, which is connected to the DSP via the ADC module.
[0013] The principle and effects of this utility model will be further explained below with reference to the above technical solution and the accompanying drawings: This invention adjusts the tension of the guitar strings using a driving device. During adjustment, the mounting portion formed by the semi-enclosed through-groove on the mounting plate undergoes slight deformation in the deformation zone as the string tension changes. Strain gauges attached to this deformation zone convert the deformation into corresponding signals, providing real-time feedback on the current string tension. The driving device passes through the through-hole in the mounting portion and, via a movable connecting component, drives the tuning pins to rotate around the mounting base, precisely changing the string winding length to adjust the tension. Compared to manually adjusting the guitar's pitch, this structure eliminates the need for the player to rely on experience to test the sound or control the tuning pin rotation angle, completely freeing them from dependence on experience. Simultaneously, the driving device can quantitatively adjust the tuning pin rotation, avoiding uneven force application during manual operation and solving the problems of low efficiency, poor precision, and insufficient stability associated with manual adjustment. Attached Figure Description
[0014] Figure 1This is a schematic diagram of the automatic pitch-changing structure for guitar described in an embodiment of the present invention; Figure 2 This is a schematic diagram (hidden cover plate) of the automatic pitch-changing structure for guitar described in an embodiment of this utility model. Figure 3 This is a schematic cross-sectional view of the automatic transposition structure for guitar described in an embodiment of the present invention. Figure 1 ; Figure 4 for Figure 3 A magnified view of a portion of the image; Figure 5 This is a schematic cross-sectional view of the automatic transposition structure for guitar described in an embodiment of the present invention. Figure 2 ; Figure 6 This is a magnified view of a portion of the image.
[0015] Figure Labels
[0016] 11-Outer shell, 12-Cover plate, 2-Mounting bracket, 3-Mounting piece, 4-String shaft, 41-Connecting hole, 42-Protruding ring, 5-Mounting base, 51-Mounting hole, 52-Annular groove, 6-Reducer, 61-Power output shaft, 62-Connecting rod, 7-Drive motor, 8-PCB board. Detailed Implementation
[0017] To facilitate understanding by those skilled in the art, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments: like Figure 1-6 An automatic tuning mechanism for a guitar includes a headstock with a mounting bracket 2 inside. A mounting plate 3 is fixedly mounted on the mounting bracket 2. The mounting plate 3 has a mounting portion for mounting a tuning pin 4. The mounting portion is enclosed by a semi-enclosed through-groove formed on the mounting plate 3. A deformation zone is formed at the junction of the mounting portion and the mounting plate 3, and a strain gauge is attached to the deformation zone. A mounting base 5 is fixedly mounted at the end of the mounting portion away from the deformation zone. The tuning pin 4 is rotatably mounted on the mounting base 5, and its axis is perpendicular to the mounting plate 3. A driving device is also provided on the mounting bracket 2. The power output shaft 61 of the driving device is coaxially arranged with the tuning pin 4. A through hole is provided on the mounting portion corresponding to the power output shaft 61. The power output shaft 61 passes through the through hole and is drivenly connected to the tuning pin 4 via a movable connecting assembly to drive the tuning pin 4 to rotate.
[0018] In this utility model, the mounting bracket 2 is fixedly installed inside the headstock to provide a mounting base for the mounting plate 3, the mounting seat 5, and the drive device, thereby enabling the mounting plate 3, the mounting seat 5, and the drive device to be installed on the headstock.
[0019] In this invention, the mounting base 5 is mounted on the mounting part of the mounting plate 3. The tuning peg 4 on the mounting base 5 is used for mounting guitar strings. After the strings are mounted on the tuning peg 4, the tension of the strings on the tuning peg 4 is transmitted to the deformation area through the mounting part, causing the deformation area on the mounting plate 3 to undergo elastic deformation. At this time, the strain gauge will deform along with the deformation area, thereby generating a corresponding change in resistance. The tension of the strings can then be calculated based on the change in resistance of the strain gauge. Then, based on the correspondence between pitch and string tension, the tuning peg 4 is rotated at a certain angle by the driving device, which can wind or unwind the strings on the tuning peg 4, thereby adjusting the string tension. The strings can be adjusted to the corresponding tension (i.e., adjusted to the corresponding pitch), thus enabling the guitar to be transposed.
[0020] Compared to manually adjusting the pitch of a musical string, this invention adjusts the string tension via a drive device, completely eliminating reliance on the performer's experience and solving the problems of low efficiency, poor precision, and insufficient stability associated with manual adjustment. Specifically, the strain gauge has a high sensitivity response to minute deformations in the deformation zone (capable of capturing deformation amplitudes of ±0.01mm). Its resistance change is converted into a digital signal by the ADC module and transmitted to the DSP. The DSP can accurately calculate the difference between the current tension and the target tension based on a preset "pitch-tension correspondence database" (e.g., the standard pitch E corresponds to a string tension of 5.5kg, A corresponds to 7.2kg, etc.), and then send a quantitative control command to the drive device. For example, when it is necessary to raise the pitch from C to G, the DSP can directly calculate that the string needs an additional 1.3kg of tension and control the drive device to rotate the tuning pin 4 by a specific angle, such as 2°, to achieve precise matching of "tension-pitch". This avoids the tedious operation of "repeatedly testing the pitch" during manual adjustment and is especially suitable for the need for "instant key changes" in live performances.
[0021] Furthermore, the movable connection assembly includes a connecting rod 62 fixedly disposed at the top end of the power output shaft 61, the connecting rod 62 being disposed perpendicular to the power output shaft 61; the movable connection assembly also includes a limiting groove formed at the bottom end of the chord shaft 4, the connecting rod 62 being located within the limiting groove, for driving the chord shaft 4 to rotate around its own axis by pushing the limiting groove.
[0022] In this embodiment, the limiting groove is elongated, and the connecting rod 62 is located in the limiting groove. When the connecting rod 62 rotates under the drive of the power output shaft 61, the end of the connecting rod 62 abuts against the inner wall of the limiting groove, thereby pushing the limiting groove to rotate, that is, pushing the chord shaft 4 to rotate around its own axis. Preferably, the connecting rod 62 is a round rod, and the width of the limiting groove is 102%-105% of the diameter of the connecting rod 62. This gap design can accommodate small radial displacements of the chord shaft 4, while minimizing power transmission lag.
[0023] In this embodiment, since the connection structure between the limiting groove and the connecting rod 62 is a movable connection structure, when the string pulls the tuning peg 4 and causes a slight deflection, it will not affect the power transmission between the connecting rod 62 and the limiting groove. This ensures that the driving device can smoothly drive the tuning peg 4 to rotate and wind or unwind the string connected to the tuning peg 4, thereby achieving the adjustment of the string tension.
[0024] Furthermore, the mounting base 5 has a vertically penetrating mounting hole 51, which is connected to the penetrating hole; the chord shaft 4 is rotatably inserted into the mounting hole 51, and an annular groove 52 is provided on the inner side wall of the mounting hole 51. A protruding ring 42 is provided on the outer side wall of the chord shaft 4 corresponding to the annular groove 52, and the protruding ring 42 is slidably embedded in the annular groove 52.
[0025] In this embodiment, the tuning pin 4 is rotatably connected to the mounting base 5 by being inserted into the mounting hole 51. The protruding ring 42 provided on the tuning pin 4 is slidably embedded in the annular groove 52 of the mounting hole 51. Under the premise of ensuring that the tuning pin 4 can rotate smoothly relative to the mounting base 5, it can be ensured that the tuning pin 4 will not detach from the mounting base 5.
[0026] Furthermore, the driving device includes a drive motor 7 fixedly mounted on the mounting bracket 2 and a reducer 6 drivenly connected to the drive motor 7, and the power output shaft 61 is the output shaft of the reducer 6.
[0027] In this embodiment, the drive device adopts a combination design of "drive motor 7 + reducer 6": drive motor 7 provides basic power, and reducer 6 reduces the output speed of motor 7 and increases the output torque through gear meshing or planetary gear structure. Since guitar tuning requires precise control of the rotation angle of the tuning pin 4, reducer 6 can convert the high-speed, low-torque output of drive motor 7 into low-speed, high-torque output, ensuring that the power output shaft 61 can drive the tuning pin 4 to rotate at a slow and steady speed, while providing sufficient torque to overcome the tension of the strings.
[0028] Furthermore, the headstock also includes a shell 11 with an opening at the top, and a cover plate 12 is detachably provided at the opening of the shell 11; the mounting bracket 2 is located inside the shell 11, and the cover plate 12 has a receiving hole corresponding to the mounting seat 5, and the mounting seat 5 and the tuning peg 4 on it extend through the receiving hole to the outside of the shell 11.
[0029] In this embodiment, the outer shell 11 is a box-shaped structure with an open top, which encloses the internal core components such as the mounting bracket 2, the drive device, and the PCB board 8, thus isolating them from external dust and moisture and protecting them. In addition, the cover plate 12 is fixed to the opening of the outer shell 11 by buckles or screws, and its detachable structure facilitates the inspection and replacement of internal components. The receiving holes on the cover plate 12 correspond one-to-one with the mounting base 5, allowing the mounting base 5 and the tuning peg 4 to extend through the cover plate 12 to the outside of the outer shell 11 without affecting the normal connection between the strings and the tuning peg 4, while completely hiding the internal components and maintaining the integrity and aesthetics of the headstock.
[0030] Furthermore, the portion of the tuning pin 4 located outside the mounting base 5 has a connecting hole 41, which extends through the tuning pin 4 along a direction perpendicular to its axis.
[0031] In this embodiment, the connecting hole 41 on the tuning peg 4 is used for the string to pass through. After the string passes through the connecting hole 41, it is then tied to the tuning peg 4. Compared with the traditional "slot-type fixation" of the tuning peg 4, its connection structure is more stable and reliable, and it is less prone to slippage.
[0032] Furthermore, a PCB board 8 is also fixedly mounted on the mounting bracket 2. The PCB board 8 integrates a DSP, a Bluetooth module, and an ADC module. The DSP is connected to the strain gauge through the ADC module.
[0033] In this embodiment, the PCB board 8 constitutes an automatic transposition control system based on tension feedback: the strain gauge converts the deformation signal of the mounting part (corresponding to the string tension) into an analog electrical signal, which is then converted into a digital signal by the ADC module and transmitted to the DSP. The DSP calls the preset "pitch-tension correspondence database" (established based on standard string parameters), compares the theoretical tension value corresponding to the target pitch with the current tension value, calculates the adjustment difference, and sends a control command to the drive device to drive the string shaft 4 to rotate to wind up or release the string until the current tension value matches the theoretical tension value.
[0034] Furthermore, the PCB board 8 also integrates a Bluetooth module.
[0035] In this embodiment, the Bluetooth module is used to enable communication between the DSP and an external terminal (such as a mobile APP). The performer can select the target key and view real-time tension data through the APP.
[0036] Furthermore, it also includes a microphone, which is connected to the DSP via the ADC module.
[0037] In this embodiment, the pickup needs to be installed on the body of the instrument near the strings to pick up the actual pitch signal generated by the string vibration, thereby increasing pitch feedback and forming a "tension-pitch dual verification" control system: the tension signal collected by the strain gauge and the actual pitch analog signal collected by the pickup are converted into digital signals by the ADC module and transmitted to the DSP. The DSP first uses the tension signal as a basic reference, and at the same time uses the actual pitch detected by the pickup as the final judgment standard to dynamically correct the drive command to eliminate the deviation between the pitch corresponding to the theoretical tension and the actual pitch detected by the pickup. For example, when the string is "at the tension standard but the pitch is deviated" due to aging, temperature and humidity changes or material differences (such as the theoretical 5.5kg tension corresponds to E, but the actual pitch of the old string under this tension is Eb), the DSP will use the actual pitch detected by the pickup as a reference to dynamically adjust the drive command until the actual pitch and the target pitch are completely matched.
[0038] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.
Claims
1. An automatic transposition mechanism for a guitar, comprising a headstock, characterized in that, The headstock is equipped with a mounting bracket, on which a mounting plate is fixedly mounted. The mounting plate has a mounting portion for mounting the tuning pin, which is enclosed by a semi-enclosed through groove. A deformation zone is formed at the junction of the mounting portion and the mounting plate, and a strain gauge is attached to the deformation zone. A mounting base is fixedly mounted at the end of the mounting portion away from the deformation zone. The tuning pin is rotatably mounted on the mounting base, and its axis is perpendicular to the mounting plate. The mounting bracket is also equipped with a driving device. The power output shaft of the driving device is coaxial with the tuning pin. A through hole is provided on the mounting portion corresponding to the power output shaft. The power output shaft passes through the through hole and is driven to the tuning pin through a movable connecting assembly to drive the tuning pin to rotate.
2. The automatic transposition structure for a guitar according to claim 1, characterized in that, The movable connection assembly includes a connecting rod fixedly disposed at the top end of the power output shaft, the connecting rod being disposed perpendicular to the power output shaft; the movable connection assembly also includes a limiting groove formed at the bottom end of the chord shaft, the connecting rod being located within the limiting groove, for driving the chord shaft to rotate around its own axis by pushing the limiting groove.
3. The automatic transposition structure for a guitar according to claim 2, characterized in that, The mounting base has a vertical through-hole, which is connected to the through-hole. The chord shaft is rotatably inserted into the mounting hole. An annular groove is provided on the inner side wall of the mounting hole, and a protruding ring is provided on the outer side wall of the chord shaft corresponding to the annular groove. The protruding ring is slidably embedded in the annular groove.
4. The automatic transposition structure for a guitar according to claim 1 or 3, characterized in that, The driving device includes a drive motor fixedly mounted on the mounting bracket and a speed reducer connected to the drive motor, wherein the power output shaft is the output shaft of the speed reducer.
5. The automatic transposition structure for a guitar according to claim 4, characterized in that, The headstock also includes a shell with an opening at the top, and a cover plate is detachably provided at the opening of the shell; the mounting bracket is located inside the shell, and the cover plate has a receiving hole corresponding to the mounting seat, and the mounting seat and the tuning pegs on it extend through the receiving hole to the outside of the shell.
6. The automatic transposition structure for a guitar according to claim 1, characterized in that, The portion of the tuning pin located on the outside of the mounting base has a connecting hole, which extends through the tuning pin along a direction perpendicular to its axis.
7. The automatic transposition structure for a guitar according to claim 1, characterized in that, A PCB board is also fixedly mounted on the mounting bracket. The PCB board integrates a DSP and an ADC module. The DSP is connected to the strain gauge through the ADC module.
8. The automatic transposition structure for a guitar according to claim 7, characterized in that, The PCB board also integrates a Bluetooth module.
9. The automatic transposition structure for a guitar according to claim 7, characterized in that, It also includes a microphone, which is connected to the DSP via the ADC module.