Patent ID: 12254856

Throughout this description, elements appearing in figures are assigned three-digit reference designators, where the most significant digit is the figure number and the two least significant digits are specific to the element. An element that is not described in conjunction with a figure may be presumed to have the same characteristics and function as a previously-described element having a reference designator with the same least significant digits.

DETAILED DESCRIPTION

FIG.1is a perspective view of a conventional pedal-operated hi-hat cymbal assembly20. The hi-hat cymbal assembly20includes a pair of metallic, typically bronze, cymbals22a,22bmounted near the top of a vertical stand24supported by lower legs26. While the lower cymbal22ais fixed with respect to the stationary stand24, the upper cymbal22bis fixed with respect to a movable rod28that slides within the hollow stand24. The rod28extends downward through the stand24and connects at its lower end to the front end of a foot pedal30whose rear end is mounted to pivot about a floor bracket32. The foot pedal30incorporates a spring mechanism (not shown) which biases its front end upward so that a drummer need only push downward on the foot pedal to cause the cymbals22a,22bto come together and make an acoustic noise. The foot pedal30automatically returns to its raised position when the drummer's foot lifts up. As mentioned above, the velocity and force applied to the foot pedal30can be varied to modulate the acoustic sound.

FIG.2is a vertical sectional view through an electronic hi-hat cymbal assembly40of the present application. Although not shown completely, the hi-hat cymbal assembly40is mounted at the top of a stationary vertical stand42supported on the floor with legs, for example. The stand42is hollow and a rod44is arranged to move up and down within an inner throughbore. The rod44connects to a lower foot pedal, such as the ones shown inFIG.1, to actuate the hi-hat cymbal assembly40.

The rod44extends upward beyond the top of the stand42and is fixed to an upper housing46to which an upper cymbal48mounts. The cymbal48is a simulated cymbal as it does not actually strike a lower cymbal to make an acoustic sound. Indeed, in this embodiment there is no lower cymbal as the sound produced does not depend on the acoustic sound generated by the impact between two physical cymbals. Typically, the cymbal48is made of a polymer, though any lightweight material may be utilized. Alternatively, bronze or other metallic materials may be used, with the simulated cymbal being a solid disk, perforated, or generally formed from any rigid materials and with any configuration available on the market. The simulated cymbal just does not need to strike a paired cymbal to make sounds.

An upper nut50may be fastened to a top end of the rod44to hold the cymbal48against the upper housing46. The upper housing46moves up and down with the rod44relative to a lower housing52, carrying the cymbal48with it. The lower housing52, in turn, is fixed with respect to a bulkhead54mounted to the top of the stationary stand42. The upper housing46and cymbal48thus move up and down with respect to the bulkhead54on which the lower housing52is mounted.

The upper housing46and the lower housing52formed the main components in a transducer assembly of the hi-hat cymbal assembly40, and are shown in perspective inFIGS.4and5. The stationary lower housing52has a generally tubular main body60with three tabs62extending outward from an upper edge thereof. The bulkhead54widens outward from a lower end of the tubular main body60. Each of the tabs62has an outer ramp surface64and is mounted in a cantilevered fashion due to vertical slits66formed in the tubular main body60. The upper housing46is shown inverted inFIG.4to illustrate a horizontal flange70extending outward from a lower end of a generally tubular cup72and surrounding a cylindrical inner cavity74within the main body. The main body includes three vertical slots76extending longitudinally along a majority of its length.

The inner cavity74of the upper housing46is configured to fit downward over the tubular main body60of the lower housing52and be retained thereon. More particularly, the cavity74closely surrounds the tubular main body60of the lower housing52, and as the upper housing46is pressed downward onto the main body of the lower housing52a lower circular rim78around the inner cavity74contacts the outer ramp surfaces64of each of the tabs62. Downward movement of the upper housing46cams the cantilevered tabs62inward to permit the upper housing to descend down around the lower housing main body60. At some point, the three tabs62flex back outward into the vertical slots76in the tubular cup72of the upper housing46. In this way, the upper housing46is captured by the lower housing52, but may move up and down by virtue of the tabs62within the elongated slots76. This arrangement also prevents relative rotational movement of the upper housing46on the lower housing52. The movable upper housing46has a down position limited by the stationary lower housing52. More particularly, the horizontal flange70come into contact with the wider bulkhead54which stops further downward movement of the upper housing46and cymbal48mounted thereon.

With reference back toFIG.2, a coil spring80is mounted around the rod44between the movable upper housing46and the stationary lower housing52to bias the upper housing upward. A soft washer or buffer82made of a compressive material such as rubber is desirably placed on the bulkhead54to cushion the impact of the upper housing46when it displaces downward relative to the lower housing52with force. The buffer82may be annular and extend evenly around and between the bottom face of the flange70and the top face of the bulkhead54. Alternatively, a series of buffers82may be distributed between the two impacting surfaces.

FIG.2also shows a magnet84carried by the upper housing46. The magnet84mounts to the inside of the tubular cup72of the upper housing46so as to be exposed within the cavity74, as seen inFIG.4. The magnet84is aligned with and translates up and down relative to and alongside a Hall effect sensor86mounted to the tubular main body60of the lower housing52, seen inFIG.5. Due to the concentrically nature of the tubular main body60and tubular cup72, the magnet84lies radially outside the sensor86and translates alongside it with a gap permitting sliding movement of 1 mm or less. The vertical travel of the rod44and movable upper housing46may be about 18 mm which corresponds to the vertical dimension of the sensor86, with the magnet84remaining adjacent to the sensor to prevent magnetic decoupling.

The Hall effect sensor86comprises a circuit board and may be obtained off-the-shelf from various vendors, such as a DRV5056 Unipolar Ratiometric Linear Hall Effect Sensor from Texas Instruments, of Dallas, TX. The DRV5056 Hall effect sensor has a detection range is in the region of 18 mm. As the magnet84translates alongside the Hall effect sensor86, the sensor generates varying electronic signals. By calibrating these electronic signals and converting them using a processor and an amplifier (not shown), distinctive desirable hi-hat sounds can be produced. The mounting positions of the magnet84and Hall effect sensor86may be reversed, though the sensor comprises a circuit board which is easier to connect to associated electronics if mounted on the stationary housing.

FIGS.3A and3Bare enlargements of the sectional view inFIG.2showing two different operating positions and the relative positioning between the magnet84and the Hall effect sensor86. The magnet84is arranged to have two vertically separated poles—indicated with S for South and N for North.FIG.3Bshows a lower end of the movable upper housing46as it contacts the soft buffer82on the bulkhead54of the stationary lower housing52, which is the “closed” position as indicated by the schematic position list to the left. As with acoustic cymbals coming together, the particular sounds are generated when and how the movable housing46contacts the stationary housing52, which is felt by the drummer's foot on the pedal. Of course, the distance the movable housing46is raised and its velocity in striking the stationary housing52are also factors in the sound produced, all of which are determined by movement of the magnet84as detected by the Hall effect sensor86.

FIG.6Ais a perspective view of an alternative stationary housing52′ of the transducer assembly having both a Hall effect sensor86and a pair of supplemental sensors90,92, andFIG.6Bis a sectional view through an electronic hi-hat cymbal assembly showing exemplary locations of the supplemental sensors. The supplemental sensors90,92provide alternative/additional methods of control of the sound output of any of the hi-hat cymbal assemblies described herein. Added sensors may be utilized to match the “mechanical feel” of the hi-hat cymbal to the sensor output, and may be useful to sense the exact point where the closed pedal hits the closed stop.

In one example, a piezo-electric sensor90is added to the stationary housing52′ or anvil of the assembly. The piezo-electric sensor90may comprise an annular disk-shaped element with a flexible central portion supported around the perimeter. The central flexible portion, or diaphragm, is bent slightly when the movable housing46descends and slams into the rubber buffer82provided for cushioning. The central portion of the piezo-electric sensor90may be only 1 mm thick and needs to flex only a fraction of a millimeter to output a change in voltage. This small voltage change can then be read by the associated electronics to give an indication of exactly when and at what velocity the pedal was closed. Consequently, the piezo-electric sensor90provides a highly reliable and accurate signal defining when the pedal hits the “closed” position, and how fast or hard the pedal is closed.

Likewise, a force sensing resistor (FSR) sensor92may be added to the stationary housing52′. The FSR sensor92is similar to the piezo-electric sensor90in that it senses small changes in pressure. A typical FSR sensor92consists of two small mylar sheets, one of which has silver interdigits printed on it and the other a resistive ink. When the resistive ink presses against the interdigits, a circuit is formed, and the resistance of the circuit varies according to the pressure. Consequently, as the pedal of the hi-hat assembly is pressed down, a voltage is derived by the FSR sensor92that is proportional to the pressure. The voltage generated by the FSR sensor92is an accurate point at which the pedal is closed, but also provides a wide controller signal for any “after pressure” exerted on the pedal. That is, there may not be enough range in the output of the Hall effect sensor86after the pedal is closed to get a desired signal for the aftertouch sound. The FSR sensor92gets squeezed after the pedal is fully closed and provides additional control for this aftertouch sound.

As seen in the cross-section section ofFIG.6B, either or both of the piezo-electric sensor90and FSR sensor92may be fitted in shallow wells on the top surface of the bulkhead54. Pressure to the sensors is thus transmitted through the rubber buffers82from the downwardly moving housing46. Both sensors90,92are connected via wires (not shown) to the sound control system. Satisfactory performance of the electronic hi-hat cymbals described herein may be attained with just the Hall effect sensor86, but more accuracy and expression, so-called “pro-level performance,” may be attained with the addition of one or both of the sensors90,92. That is, the Hall effect sensor86works by software predicting the position of the moving housing46through a changing magnetic field, and adding the sensors90,92which respond to physical feedback provides additional accuracy.

As is well known in the art, and schematically illustrated inFIG.7, the two poles of the magnet84generate a toroidal magnetic field having a horizontal midplane M coinciding with the junction of the two poles. That is, the magnetic field a magnetic dipole moment, or strength, points in the direction of lines between the South and North poles of the magnet. Relative to the Hall effect sensor86, the direction of the magnetic field switches at the horizontal midplane M between the two poles, which transition can be sensed by the sensor. Moreover, the Hall effect sensor86is calibrated to sense the strength of the magnetic field proportional to the distance from the midplane M between the two poles, as well as the velocity and acceleration of the relative movement between the sensor and the magnet and output a voltage proportional to this movement The resulting signal generated by the Hall effect sensor86is then processed using specialized software and converted into electric signals which can be amplified through speakers for the different hi hat sounds. Of course, the relative vertical position of the poles (South up or down) is reversible.

Additionally, though not shown, piezo sensor and position switches may be incorporated into the playing surface as per current designs. The number of position switches varies, and could be as few as two (bell and edge) and as many as 5 (bell, hi bow, med bow, low bow & edge).

FIG.8is a vertical sectional view through an electronic hi-hat cymbal assembly80of the present application having a simulated lower cymbal. Although not shown completely, the hi-hat cymbal assembly100is mounted at the top of a stationary vertical stand102supported on the floor with legs, for example. The stand102is hollow and a rod108is arranged to move up and down within an inner throughbore. The rod108connects to a lower foot pedal, such as the ones shown inFIG.1, to actuate the hi-hat cymbal assembly100.

The rod108extends upward beyond the top of the stand102and is fixed to an upper housing114to which an upper cymbal104mounts. The cymbal104is a simulated cymbal as it does not strike a lower cymbal to make sound. Typically, the cymbal104is made of a polymer, though any lightweight material may be utilized. An upper nut106may be fastened to a top end of the rod108to hold the cymbal104against the upper housing114. The upper housing114moves up and down with the rod108relative to a lower housing110, carrying the cymbal104with it. The lower housing110, in turn, is fixed with respect to a simulated lower cymbal112mounted to the top of the stationary stand102. A coil spring116is mounted around the rod108between the movable upper housing114and the stationary lower housing110to bias the upper housing upward. The upper housing114and cymbal104thus move up and down with respect to the lower housing110and simulated cymbal112, simulating an acoustic cymbal assembly such as inFIG.1.FIG.8shows a stationary rubber cushion or buffer118placed on a top face of the lower cymbal112whose purpose is described below.

FIG.8also shows a magnet124carried by the upper housing114. The magnet124to a main body of the upper housing114so as to be exposed within an inner cavity of the housing114, much as with the earlier embodiment ofFIG.2. The magnet124is aligned with and translates up and down relative to a Hall effect sensor126mounted to the lower housing110, seen enlarged inFIG.9A. The Hall effect sensor126comprises a circuit board and may be obtained of off-the-shelf from various vendors, as mentioned above. As the magnet124translates alongside the Hall effect sensor126, the sensor generates varying electronic signals. By calibrating these electronic signals and converting them using a processor and an amplifier (not shown), distinctive desirable hi-hat sounds can be produced.

FIGS.9A-9Dare enlargements of the sectional view inFIG.8showing different operating positions.FIG.10is an enlargement of a lower end of the movable housing114of the transducer assembly fromFIG.9A, illustrating a lower elastomeric annular molding or foot120. The foot120is a compressible material which cushions and influences the position of the movable housing114when it contacts the stationary rubber buffer118directly below it. There also may be a soft annular washer122(FIG.10) made of a compressive material such as rubber placed between flanges of the movable upper housing114and the stationary housing114to absorb forces and reduce associated noise when the upper cymbal104and upper housing114are released to move upward under influence of the spring116.

The annotation inFIG.9Aindicates that there is a first distance of travel between full open and full closed such as 16 mm, but a total second travel distance of 18 mm which takes into account after the foot120contacts the stationary rubber buffer118. There is thus a 2 mm after touch travel. These distances may be altered to create different cymbal actions, and are used as an example here to match the Texas Instruments DRV5056 Hall effect sensor mentioned above.

InFIG.9B, the pedal is depressed lightly down to close the hi-hat and create a so-called “loose sizzle.” In this position, the outer extent of the foot120has come into contact with the buffer118, but an inner thicker anvil portion121of the foot120remains slightly elevated above the buffer118. This position and movement is calibrated into the sensor126to create the “loose sizzle” sound.

InFIG.9C, the pedal is depressed firmly down to close the hi-hat. In this position, the outer skirt of the foot120flexes such that the inner anvil portion121comes into contact with the buffer118. This position and movement is calibrated into the sensor126to create the closed sound of the cymbal assembly80.

Finally,FIG.9Dshows the pedal after having been depressed down hard to close the hi-hat and push the inner anvil portion121of the foot120downward into the buffer118. This is also a closed sound but the sensor126is calibrated to generate a slightly higher pitch of sound, such as one semitone up. Each of these positions results in a different cymbal sound.

FIG.11show curves indicating both force and velocity experienced by the electronic hi-hat cymbal ofFIG.8graphed against the resulting effects generated by the system. The distances range from fully open to the left on the X-axis to closed and then farther in the “aftertouch” range, which is after the inner thicker portion of the foot120contacts the buffer118. The solid line curve V indicates the output from the Hall effect sensor126. The two force curves F1 and F2 correspond to the mechanical feedback exerted on the pedal at different stages of foot depression. An initial force curve F1 is felt during travel from the open to the “loose sizzle” commencement when the outer extent of the foot120has come into contact with the buffer118. Subsequently, the rate of force feedback increases in the second force curve F2 through the sizzle zone and into the aftertouch zone. These zones correspond to flexing of the elastomeric foot120and then impact of the inner anvil portion121of the foot120with the buffer118and deformation thereof. Various nodes or points are indicated on the curves to denote the various transitions, which points are calibrated into the software receiving the Hall effect signals to determine the desired sound created.

FIGS.12A-12Care perspective views of a stationary housing of the transducer assembly having a position-adjustable Hall effect sensor86′ thereon. As mentioned above, the Hall effect sensors described herein produce signals which are then processed using software which interprets the relative position of the moving members of the hi-hat assembly. The software can of course be calibrated at the manufacturing stage for the particular physical arrangement. Additionally, the software may possess the ability for the user to adjust the calibration settings for different sound effects. However, it may also be useful to supplement this virtual calibration with a physical calibration means. There is, the “closing point” of the hi-hat cymbal is critical for the correct feel. It is important for the software to recognize the exact point where the mechanical movement of the pedal hits the rubber covered anvil and produce a closing sample sound. Adding a mechanical way of adjusting the vertical position of either the magnet or the Hall effect sensor to adjust the calibration of the closing point is thus contemplated.

InFIGS.12A-12Cthe position-adjustable Hall effect sensor86′ comprises a small circuit board130as before mounted on a fixed panel132within a vertical slot134of the stationary housing. A threaded rod136is arranged to displace the circuit board130up and down relative to the panel132, preferably by at least a few millimeters. For example, the circuit board130and panel132may have cooperating vertical rails (not shown). The threaded rod136may pass through a similarly threaded bore (not shown) in the circuit board130so that rotation of the rod causes vertical movement of the circuit board. The threaded rod136may pass downward through the bulkhead54to a lower thumbscrew or other actuator (not shown) accessible to the user.FIG.12Bshows the circuit board130being displaced downward, whileFIG.12Cshows the circuit board displaced upward. Slight adjustments may be made in conjunction with the software calibration to control the desired sound effects.

CLOSING COMMENTS

Throughout this description, the embodiments and examples shown should be considered as exemplars, rather than limitations on the apparatus and procedures disclosed or claimed. Although many of the examples presented herein involve specific combinations of method acts or system elements, it should be understood that those acts and those elements may be combined in other ways to accomplish the same objectives. Acts, elements and features discussed only in connection with one embodiment are not intended to be excluded from a similar role in other embodiments.

As used herein, “plurality” means two or more. As used herein, a “set” of items may include one or more of such items. As used herein, whether in the written description or the claims, the terms “comprising”, “including”, “carrying”, “having”, “containing”, “involving”, and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of”, respectively, are closed or semi-closed transitional phrases with respect to claims. Use of ordinal terms such as “first”, “second”, “third”, etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements. As used herein, “and/or” means that the listed items are alternatives, but the alternatives also include any combination of the listed items.