Patent Description:
The tuning of musical instruments is an important part of their use. The tuning of a large musical instrument like the pipe organ is a regular, labor-intensive, and time-consuming task for the musician or trained personnel. The organ is comprised of single pipes, the number of which varies from one hundred to ten thousand.

Based on how they produce a tone, the organ pipes are divided into two types: flue pipes (also referred to as labial pipes); and reed pipes. The vast majority of the organ pipes are flue pipes and many organs even do not contain reed pipes. The sound of flue pipes is produced in the immobile lip of the flue pipe by the uneven flow of resonating air. The oscillation frequency of the sound waves directly depends on the length of the flue pipe. To tune a flue pipe, the length of the pipe is changed using special instruments or, for example, the solution proposed by patent application <CIT>), where the tuning element located on the tuning slot at the upper end of the resonator is moved with an electric motor.

In reed pipes, the oscillation is caused by the metal strip, or tongue, located at the bottom end of the pipe, which, as it vibrates, periodically allows or blocks the airflow into the pipe. The oscillation frequency, or pitch, of such a pipe depends of the length of the vibrating part in addition to the resonator. For tuning, the length of the vibrating part can be changed with a movable tuning wire. The moving of the tuning wire does not require much force and can occur spontaneously. This random loss of tuning, the cause for the need to periodically retune, concerns more often the reed pipes of a pipe organ. They need to be tuned at least once a week and it is also recommended to check the tuning and if necessary, retune before a concert. The tuning of reed pipes and checking their tuning takes from half an hour to several hours depending on the size of the organ.

Checking the tuning of all flue pipes normally takes from one day to several months depending on the size of the organ. Spontaneous (random) detuning of flue pipes is much slower than that of reed pipes and their tuning is usually done once a year.

In addition to the random loss of tuning described above, tuning changes also occur in a pipe organ due to fluctuation of temperature and humidity. The pitch of flue pipes depends, besides the length of the flue pipe, also on the speed of sound in air. The latter in turn depends on temperature. Therefore, a change in room temperature notably affects the tuning of flue pipes. Even a fluctuation of a few centigrade changes remarkably the pitch flue pipes. Every pipe has a certain deviation measured in Cents from its note standard frequency. Said notes standard frequencies form a chromatic scale that corresponds to organ intended temperament (equal-tempered, Werckmeister etc.). The pitch changes are similar for all flue pipes, their deviation from note standard frequency changes equally, and therefore the flue pipes will remain in consonance with each other even at different absolute frequencies. However, the problem arises with reed pipes, whose pitch is not affected by temperature in the same way as for flue pipes. Following a temperature fluctuation, reed pipes and flue pipes are no longer on the same relative pitch. As there are less reed pipes and their tuning is easier than flue pipes tuning, the flue pipes are not restored to their former pitch, but the reed pipes are manually tuned to the new pitch that has the same deviation as the flue pipes have reached due to temperature change.

Beat tunes audible to the ear between close frequencies are usually used to tune a pipe organ, making two pipes, separated by an interval of a prime or an octave, sound simultaneously. The goal is to apply the manual tuning tools until there are no more beats. At recent time, electronic frequency measuring devices equipped with microphones are also used at tuning.

Similarly to reed stops, whose pitch is less affected by temperature, digital musical instruments intended to be used simultaneously with flue pipes also need to be adjusted according to the flue pipes of the pipe organ. A solution has been disclosed in the patent <CIT>) as a method for obtaining frequency adjustment parameter for digital instruments via different options: to calculate from room temperature deviation or to measure the pitch of the flue pipes. This patent also offers the method of selectively measuring the sound of particular flue pipe, undisturbed by adjacent pipes and background noise, suggesting to use microphone installed at a short distance from the pipe to be monitored, or by a contact microphone or a piezoceramic buzzer, directly mounted against the metal surface of the pipe, or by an air flow sensor installed in appropriate position.

It is often difficult to execute the tuning as the section where the tuning should be performed is remote from the playing console. To solve this problem, the patent application <CIT>) proposes equipping the tuning wires with motors that the tuner could control from the console.

A device to semi-automatically tune the reed stops of a pipe organ, equipped with a microcontroller and a microphone in addition to motors that can move the tuning wires, is proposed in the patent <CIT>). The latter is the closest prototype to the solution provided by the present invention. The invention proposes a solution for tuning several pipes simultaneously by using band pass filters between microphone and the frequency meter to reduce tuning time.

The influence of the parameters which could affect the tone of a reed pipe have been investigated and found that for each shallot, the frequency increases linearly with thickness and linearly with air pressure (over the normal operating range of the reed) (<NPL>)).

In the patent application <CIT>) a tuning device for stopped flue pipes is disclosed, particularly suitable for control by means of a program-controlled drive, wherein a tuning opening is located in a side wall, in which a tuning slide releases a more or less high range depending on the desired tuning.

The investigations of oscillations of organ-pipes walls by means of piezoelectric polymer films that were slightly tensioned around the pipe bodies were described in scientific paper of <NPL>). With patterned and uniform sensors, respectively, the well-known elliptical oscillations of the cross section as well as an additional monopole breathing of the organ-pipe body were detected.

The patent <CIT>) describes a method of tuning a piano by independently and simultaneously measuring the oscillation of the strings while automatically tuning them, where the oscillation of the strings is detected by the electromagnetic method. Detecting the oscillation with infrared light has also been used on pianos, see https://newatlas. com/gilmore-self-tuning-piano-system/<NUM>/ (Published on <NUM> February <NUM>) [retrieved on <NUM> December, <NUM>].

There is a research publication about stationary spectra of not only sound waves generated by different organ pipes, but also of the pipes wall vibration.

There are several problems unsolved so far. There is no pipe organ tuning device that could determine by itself which particular reed pipe is sounding and, consequently, engage the corresponding reed pipe tuning mechanism. There is no method of checking the tuning of the flue pipes of a pipe organ and (self)tuning of the reed pipes without any separate tuning procedure, but conducted by the tuning system during the regular playing on the organ. The known devices for pipe organ tuning that measure the tuning, using microphones, regardless distinguishing simultaneously sounding pipes with a band pass filter, cannot accurately identify which pipe is sounding, as a pipe organ typically has several pipes with the same pitch in different stops. Furthermore, an actuator with a motor for tuning reed pipes requires separate anchorage points on the casing and on the tuning wire of a pipe; dependent on the construction of a reed pipe, it might be somewhat difficult to install it.

Thus, there is a need for a solution for an automatically tuning the pipes of a pipe organ unnoticeably during regular play of the organ, that is capable to determine selectively, which pipe is being sounded, and to get reliable measurements of the pipes' frequency, undisturbed by the neighboring sounding pipes.

The purpose of the invention is to reduce the time of the user (tuner or organist) consumed to tune the pipe organ and to tune the pipes that require more frequent tuning (the reed pipes) unobtrusively to the organist and listeners.

The object of the invention is a pipe organ reed pipe tuning device <NUM>, which includes at least one soundwave oscillation sensor <NUM>, a reed pipe tuning mechanism comprising at least an actuator <NUM>, <NUM> configured to move a tuning wire of a reed pipe and a microcontroller <NUM>, configured to control the reed pipe tuning mechanism and connected to the at least one soundwave oscillation sensor. The tuning mechanism further comprises an inertial armature <NUM>, on which the at least one actuator <NUM>, <NUM> and two anvils <NUM>, <NUM> are mounted. The two anvils are attached to the tuning wire <NUM> of the reed pipe <NUM>. The inertial armature <NUM> is configured to move the tuning wire <NUM> for controlling the vibration frequency of the reed pipe <NUM> by selectively knocking one of the two anvils <NUM>, <NUM>. The least one actuator is one or several electromagnets <NUM>, <NUM>.

The inertial armature <NUM> is accelerated with the upper <NUM> or lower <NUM> electromagnet and the momentum created by the impact with anvil <NUM> or <NUM> moves the tuning wire <NUM> that controls the pitch. The friction between the tuning wire <NUM> and the casing of a reed pipe <NUM> stops the tuning wire <NUM> from moving, when the inertial armature <NUM> picks up its speed, but the sudden impact against anvils <NUM>-<NUM> is enough to surpass this friction and to create movement.

The invention proposes using the inertial armature's position sensor <NUM>, which could be implemented by infrared LED and a photo sensor, to more effectively control the movement of the inertial armature <NUM> by the electromagnets <NUM>-<NUM>. The inertial armature's position sensor <NUM> is especially useful for reducing the drop speed of the inertial armature <NUM> after intentional knock against the upper anvil <NUM>.

Different oscillation sensors can be used as vibration input for the above-mentioned reed pipe tuning device <NUM> with a moving inertial armature <NUM>, for example, a microphone. Also, a semi-automatic tuning, where the reed pipe tuning device is controlled by an operator from a console connected to the reed pipe tuning device as described in patent application <CIT>) can be implemented. According to the current invention preferred embodiment, the measuring of fundamental vibration frequency required for tuning of the reed pipe by the tuning device <NUM> is performed by the microcontroller <NUM> according to the vibration of the accelerometer <NUM>, and the tuning of reed pipe <NUM> occurs automatically when the user sounds reed pipes during regular playing <NUM>.

The microcontroller <NUM> in the reed pipe tuning device <NUM> uses the stored desired vibration frequency without any modification for tuning if the organ is located in a room with unchangeable temperature. However, organs are often installed in churches, where the room temperature fluctuates. It is proposed that the device <NUM> comprises a room temperature and humidity sensor <NUM> in addition to the accelerometer <NUM>. Thus, the microcontroller <NUM> can be used to actualize, by means of calculating, as the function of the stored desired vibration frequency and the environmental sensor values, the desired vibration frequency, and so, when the room temperature and humidity are changed, to achieve consonance with the flue pipes <NUM> of the pipe organ, whose pitch changes based on the room temperature and humidity.

It is possible to employ the device of the invention on all pipes of an organ or only on a certain selection of them. The invention enables semi-automatic tuning, where the reed pipe tuning device is controlled by an operator from a console or automatically unobtrusively to the listeners during the playing of the pipe organ. Required is tuning of the reed pipes to the same pitch as flue pipes if the fluctuation of temperature and humidity has caused a change in the pitch of the flue pipes of the pipe organ, and to restore the tuning of the reed pipes of the pipe organ in case of random loss of tuning.

Pitch of the pipe is directly related to the fundamental frequency of the sound oscillation produced by the organ pipe (either reed pipe or flue pipe) simultaneously with sounding organ pipe itself vibrates on the same fundamental frequency of the (reed or flue) pipe. Occurrence of said vibration, detected by an accelerometer, is used in the invention to determine pipes sounding status - pipe is sounding or not sounding. To avoid false positive determination of the pipe sounding status, the vibration noise from blower or from neighboring pipes must be filtered out. Although organ has many pipes that have the same fundamental frequency, it has unique envelope of the harmonics in the spectrum of vibration. Furthermore, modern accelerometers are capable of measuring the vibration selectively in the three perpendicular axes, thus providing even more unique data pattern for filtering noise and selectively determine sounding status of the particular pipe, by matching measured harmonic amplitudes of the pipe vibration in three axes with stored unique values for the pipe. In the case that predetermined number of measured amplitudes are within predetermined range with the stored values, the vibration is considered as matching and the pipe sounding status determined as positive.

The present invention offers organ pipe tuning device, that is characterized, by using accelerometers for sounding detection and actuator means.

The present invention requires, for the tuning of a pipe organ, at least one independently operating reed pipe tuning device or preferably several connected reed pipe tuning devices, that collectively compose the tuning system of a pipe organ. An aspect not forming part of the invention is a tuning system which can also include some flue pipe tuning devices in addition to reed pipe tuning devices.

Disclosed herein, but not forming part of the present invention, is a pipe organ tuning system that comprises tuning devices, at least one or several reed pipe tuning devices <NUM> of the current invention, which in turn comprises an accelerometer <NUM> as a soundwave oscillation sensor, measuring the vibration of reed pipes <NUM>, an electrically controlled reed pipe <NUM> tuning mechanism capable of moving the tuning wire <NUM> for changing the frequency of the reed pipes, and a microcontroller <NUM> with the capability to measure the vibration frequency from the accelerometer readings, to process the frequency readings, and control the reed pipe tuning mechanism. The reed pipe tuning device <NUM> is equipped with a fastener <NUM> that enables it to be attached to the tuning wire <NUM> of a reed pipe <NUM> in such a way that the of vibration from the reed pipe <NUM> is transmitted to the accelerometer <NUM>. The accelerometer <NUM> is connected to the microcontroller <NUM>, that performs the automatic tuning of reed pipe <NUM>. The accelerometers <NUM> and tuning mechanisms, moving the tuning wire <NUM>, attached to different reed pipes <NUM> can be connected to a single microcontroller <NUM> of a reed pipe tuning device <NUM>.

The pipe organ tuning system can be implemented using various mechanisms of reed pipe tuning device <NUM> for purpose of moving the tuning wire <NUM>; in an example, not forming part of the present invention, a motor like the one described by <CIT>) may be used. The present invention proposes an inertial armature <NUM> and anvils <NUM> - <NUM>, attached to the reed pipe tuning wire <NUM> as the mechanism in the reed pipe tuning device <NUM>. The above-mentioned inertial armature <NUM>, which can rotate around the axis <NUM>, is able to move the pitch-controlling tuning wire <NUM> and change the pitch of reed pipe <NUM> by knocking the above-mentioned anvils <NUM> and <NUM>. One or several electromagnets <NUM> - <NUM> can be used as actuators for moving the inertial armature <NUM>.

Disclosed herein, but not forming part of the present invention, is a flue pipe tuning device. Most usual type of the pipe organ pipes is the flue pipes <NUM>. The pipe organ tuning system can be used with the flue pipes <NUM>, that cannot be automatically tuned with the flue pipe tuning device <NUM>, as a part of the pipe organ tuning system. The flue pipe tuning device <NUM> is attached directly to the windchest <NUM> of the pipe organ or to the flue pipes support frame (not shown in the figures) that is attached to the windchest <NUM>, so that the flue pipes <NUM> could be freely removed and replaced, for example, to perform manual tuning procedure. In order to carry vibration from the flue pipe <NUM> to the accelerometer <NUM> by touch contact, that creates mechanical connection between the accelerometer <NUM> and the flue pipe <NUM>, whereas as the fastener for the flue pipe tuning device is used a leaf spring <NUM> or other similar means. The flue pipe tuning device <NUM> comprises at least one accelerometer <NUM>, connected to the microcontroller <NUM>. The microcontrollers <NUM> of the reed pipe tuning devise <NUM> or the flue pipe tuning devise <NUM> belonging to the tuning system are connected in network of data communication that allows them to exchange information about, for example, frequencies, temperature, humidity, etc. Removing flue pipes <NUM> freely means that when removing and replacing flue pipes <NUM> from windchest <NUM>, the user does not need to go through the additional task of disconnecting and reconnecting or removing and reattaching the flue pipe tuning devices <NUM>. The flue pipe tuning device fastener <NUM> is solved by means, for example, of leaf spring that attaches flue pipe tuning device to the windchest <NUM> and ensures sufficient touch contact to the flue pipe <NUM> that allows vibration frequency measurement. Such fastener <NUM> ensures that after reinstalling the flue pipe <NUM>, the touch contact necessary to measure vibration will be restored. Fastener <NUM> allows freedom of movement in all three directions: parallel and perpendicular to the longitudinal axes of the flue pipe.

Steps <NUM> - <NUM> on the flowcharts are illustrating the method not forming part of the present invention.

This example describes the tuning of pipe organ that is located in a room with fixed temperature, which means that the room temperature does not change by more than <NUM> centigrade all year round and the pitch of flue pipes <NUM> remains persistent. Reed pipes <NUM> need more or less frequent tuning.

The reed pipe <NUM> tuning wire <NUM> moving mechanism with a motor <NUM> has threaded spindle <NUM>, that is attached to the motor <NUM> shaft and the spindle nut attached with adapter <NUM> to tuning wire <NUM>. This tuning mechanism, which is not part of the present invention, is used in some reed pipe tuning devices <NUM>.

The reed pipe tuning device <NUM> with tuning wire <NUM> moving mechanism, that uses an inertial armature, according to the present invention, is shown on <FIG>. It comprises the base plate <NUM>, which forms the base for installing the accelerometer <NUM>, microcontroller <NUM> and other electronic components. The inertial armature <NUM>, capable of turning around the axis <NUM>, is installed on the base plate <NUM>. The microcontroller <NUM> is connected by corresponding power circuits (not shown on the figure) to the electromagnets <NUM>, <NUM> mounted on the base plate <NUM>. The base plate <NUM> is attached to the tuning wire <NUM> of the reed pipe <NUM> with fasteners <NUM>, which serve also as the anvils <NUM>, <NUM>. A spring <NUM> installed between the reed pipe tuning device <NUM> and the casing of the reed pipe <NUM> is compressed during installation to such an extent that the compressing force would roughly be equal to the weight of the reed pipe tuning device <NUM>. The reed pipe tuning device <NUM> is connected to electric power supply (not shown on the figure). The tuning wire <NUM> which determines the length of the vibrating part of the reed pipe's <NUM> tongue <NUM> is fixed in the casing of the reed pipe by friction and can be moved up or down if the moving force overcomes the friction.

With smaller pipes, where less force Is required to move the turning wire <NUM>, the reed pipe tuning device <NUM> with only upper electromagnet <NUM> is used (<FIG>).

Reed pipe tuning device <NUM> mechanism equipped with motor uses electrical impulses for it control.

Reed pipe tuning device <NUM>, that has the mechanism equipped with inertial armature <NUM> performs as following:.

The reed pipe tuning device <NUM> that has only upper electromagnet <NUM> (<FIG>) performs the impact on the lower anvil for moving the tuning wire <NUM> downwards using the momentum that the inertial armature <NUM> gets from gravity.

The tuning steps d-e for all reed pipes <NUM> are performed automatically during the playing of the organ.

The second example describes tuning of the pipe organ located in a church hall that is warmer during summer (up to <NUM>) and colder during winter (<NUM>). Due to the fluctuation of the room temperature, the average pitch of the flue pipes changes and the reed pipes need retuning according to the changed pitch of the flue pipes. In addition, the reed pipes also need tuning due to random getting out of tune during winter, when the church hall is heated to maintain the temperature of <NUM>.

The pipe organ tuning system, not forming part of the present invention, similar to the first example, comprising the reed pipe tuning devices <NUM> of the invention, is used. In addition to the equipment, described in first example, the reed pipe tuning devices <NUM> include a temperature and humidity sensor <NUM>.

According to the method not forming part of the present invention, the following actions are taken (<FIG>):.

The third example, similarly to the second one, describes tuning of the pipe organ located in a church hall that is warmer during summer (up to <NUM> degrees Celsius) and colder during winter (about <NUM> degrees Celsius). Additionally to the reed pipes that need more frequent tuning, the user of the organ may wish to automatically check the tuning of flue pipes and to receive current information about the loss of their tuning.

The pipe organ tuning system, comprising the flue pipe tuning devices <NUM> and the reed pipe tuning devices <NUM>, is used (<FIG>). The following actions are taken to tune the pipe organ (<FIG>):.

The tuning steps d - g are automatically performed during the regular playing of the organ, constantly repeating steps c-g. The microcontroller <NUM> decides, based on the volume of the organ, whether to perform the tuning actions, that may create some audible sound, or to postpone them until the general sound volume of the organ is sufficient to mask them from the listener (<NUM>).

Claim 1:
A pipe organ reed pipe tuning device (<NUM>), which includes:
at least one soundwave oscillation sensor (<NUM>);
a reed pipe tuning mechanism comprising at least an actuator (<NUM>, <NUM>) configured to move a tuning wire of a reed pipe; and
a microcontroller (<NUM>), configured to control the reed pipe tuning mechanism and connected to the at least one soundwave oscillation sensor, characterized in that
the tuning mechanism further comprises an inertial armature (<NUM>), on which the at least one actuator (<NUM>, <NUM>) and two anvils (<NUM>, <NUM>) are mounted, the two anvils being attached to the tuning wire (<NUM>) of the reed pipe (<NUM>), wherein the inertial armature (<NUM>) is configured to move the tuning wire (<NUM>) for controlling the vibration frequency of the reed pipe (<NUM>) by selectively knocking one of the two anvils (<NUM>, <NUM>),
the least one actuators are one or several electromagnets (<NUM>, <NUM>).