Abstract:
A high hat cymbal has a magnetic clutch that engages the top cymbal and allows it to be controlled by a standard high hat foot pedal. When the drummer&#39;s foot is removed from the high hat foot pedal, the magnetic clutch strikes a mechanical arm, which causes the magnetic clutch to disengage without any action, required on the part of the drummer. The top cymbal can be re-engaged by the magnetic clutch so that the high hat foot pedal can now be operated again, simply by depressing the high hat foot pedal. A trip bar may be provided to provide for automatic disengagement of the clutch mechanism.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of co-pending U.S. patent application no. 12/942,548, filed Nov. 9, 2010, which claims the benefit under 35 USC 119(e) of U.S. provisional application No. 61/259,615, filed Nov., 9, 2009, the contents of which are herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to the field of percussion instruments, such as high hat cymbals, and in particular to a locking mechanism for use in such instruments. 
     BACKGROUND OF THE INVENTION 
     Most bands playing popular modern music will include a drummer, playing a drum set, also called a drum kit. The drum kit typically consists of a bass drum, snare drum, tom toms, cymbals, and a high hat cymbal. Modern drumming techniques have evolved significantly since the advent of rock and roll music in the 1950&#39;s. Modern drummers have a wide variety of percussive instruments, as well as the typical kit components, and they arrange these different instruments to suit their particular tastes and styles. 
     A high hat cymbal actually consists of two cymbals facing each other. The high hat cymbal is struck by a drumstick, but is also operated using a foot pedal. The foot pedal operation consists of “closing and opening” the high hat, that is bringing the top cymbal into tight contact with the bottom cymbal to make a staccato sound, known as closing the high hat, or allowing the top cymbal to rise into looser contact with the bottom cymbal creating a ringing or less staccato sound, known as opening the high hat. 
     The drummer keeps the high hat in the closed position by depressing the foot pedal. Releasing the foot pedal allows a spring mechanism to raise the top cymbal into the open position. With a conventional high hat arrangement, the drummer must have a foot on the high hat foot pedal to operate the instrument. Also, to operate the high hat cymbal in the closed position, the drummer must still have one foot on the foot pedal. This “ties up” one foot and makes it impossible for the drummer to use that foot to operate other instruments. 
     The bass drum is struck by a mallet, which is operated by a foot pedal. Modern drumming techniques, especially in rock genres such as hard rock, heavy metal, speed metal, etc., call for a technique that uses two bass drum pedals, commonly referred to as “double bass”. Since the drummer only has two feet, he or she cannot operate two bass drum pedals and a high hat pedal simultaneously. 
     Since the desired default position for the high hat cymbal is the closed position, it is known to disengage the top cymbal from the central shaft that ties it to the foot pedal in order to drop into a closed position with the bottom cymbal. Ideally, disengaging the top cymbal and allowing it to fall into the closed position should be done with minimum distraction to the drummer. However, the top cymbal needs to be re-engaged so that the drummer can operate it using the high hat foot pedal, again, while minimizing distractions to the drummer. In summary, the top cymbal needs to be engaged and disengaged without interfering with the drummer&#39;s playing in any way. 
     Attempts have been made to solve this problem in the prior art, for example, as described in U.S. Pat. Nos. 4,667,562; 4,730,532; 4,928,567. These designs require action on the part of the drummer, leading to distraction, or are overly complex, see, for example, U.S. Pat. No. 5,028,776, or create additional clutter in the drummers playing area. 
     SUMMARY OF THE INVENTION 
     While our U.S. Pat. No. 7,671,263 provides an effective solution, the present invention represents a further improvement of the solution disclosed in that patent. 
     Like the above patent the present invention addresses the problems arising in the prior art in one aspect by providing automatic disengagement of the upper cymbal as it returns to its raised position by operation of the spring mechanism associated with the foot pedal, and in another aspect by providing an advantageous locking mechanism that is reliable and less complex than the prior art. 
     Thus, in accordance with one aspect of the invention there is provided a locking mechanism for a musical percussion instrument comprising a pair of upper and lower cymbals, wherein the lower cymbal is fixedly mounted on a tubular support, and the upper cymbal can be raised or lowered by means of a foot-operated control rod extending within the tubular support, the locking mechanism comprising a magnetic clutch mechanism mountable on the control rod for releasably bringing said upper cymbal into engagement with the control rod, and wherein the magnetic clutch mechanism includes respective first and second mating surfaces which in their normal position are engaged with each other by magnetic attraction, said mating surfaces being tiltable relative to each other; and wherein said clutch mechanism includes a trip member operable upon actuation to tilt at least one of said mating surfaces so as to at least partially separate mating surfaces and thereby break the engagement and allow said upper cymbal to fall onto said lower cymbal. 
     In a second aspect the invention provides a hi-hat cymbal set, comprising a pair of upper and lower cymbals, wherein the lower cymbal is fixedly mounted on a tubular support, and the upper cymbal can be raised or lowered by means of a foot-operated control rod extending within the tubular support, the locking mechanism; and a magnetic clutch mechanism mountable on the control rod for releasably bringing said upper cymbal into engagement with the control rod, and wherein the magnetic clutch mechanism includes respective first and second mating surfaces which in their normal position are engaged with each other by magnetic attraction, said mating surfaces being tiltable relative to each other; and wherein said clutch mechanism includes a trip member operable upon actuation to tilt at least one of said mating surfaces so as to at least partially separate mating surfaces and thereby break the engagement and allow said upper cymbal to fall onto said lower cymbal. 
     It is possible to tilt either surface. On one embodiment, the lower surface can be in the form of a disk attached to the upper cymbal by a resilient grommet, for example, which is made of rubber or elastomeric material. In this embodiment, the upper cymbal may be mounted on a sleeve slidable on the tubular support. 
     This mechanism is well adapted for use with the trip bar, but it nevertheless offers advantages over the prior art in terms of reliability and simplicity. The tilting of the mating surface releases the magnetic engagement and allows the upper cymbal to fall onto the lower cymbal in the closed position, yet also ensures quick re-engagement of the clutch when the upper collar component is brought back down onto the lower collar component by operating the foot pedal. As soon as the mating surfaces come into engagement, the clutch re-engages without the need for any movable locking members or the like. 
     The drummer can now strike the hi-hat cymbals in the closed position while working the second bass pedal, or other instrument. When he/she wishes to operate the high hat again, he/she simply depresses the foot pedal causing the vertical shaft and the second section to come down. The magnets from the second section will engage the steel flange from the first section, and now the top cymbal is connected to the vertical shaft, which is connected to the high hat foot pedal and the drummer is now in full control of the high hat. 
     In another aspect the invention provides a releasable locking kit for a high hat cymbal set, comprising a pivotal hook member mountable on a control rod of the high hat cymbal set; a block fixedly mountable on a cymbal holder that is slidably mounted on the control rod, said block being engageable by the pivotal hook member to releasably lock the cymbal to the control rod; and an overhanding trip bar for pivoting said hook member when the cymbal is raised beyond a certain height to release said cymbal from locking engagement with the control rod. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which: 
         FIGS. 1A and 1B  show an embodiment of the invention in the engaged position; 
         FIG. 2  shows the embodiment in the tripped position; 
         FIG. 3  shows the embodiment in the disengaged position; 
         FIG. 4  shows the embodiment in the disengaged position; 
         FIG. 5  is an exploded view of the embodiment; 
         FIG. 6  shows yet another embodiment with a trip bar; 
         FIGS. 7A to 7H  show yet another embodiment in different configurations, with  FIGS. 7E to 7H  showing a detail of the clutch mechanism in different stages of engagement; and 
         FIG. 8  shows a still further embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A locking mechanism in accordance with an embodiment of the invention is shown in  FIGS. 1   a  and  1   b . The lower cymbal  50   b  of a hi-hat cymbal set is fixedly mounted on the tubular support  51  by means of collar  52  in a conventional manner. The upper cymbal  50   a  is mounted on an externally threaded sleeve  53 , which slides on tubular support  51 . Depression of the foot pedal (not shown) will bring the upper cymbal  50   a  into contact with the lower cymbal  50   b  as a result of the control rod  60  travelling up and down within the tubular support  51 . Typically the control rod  60  is spring-biased into the raised position so that depression of the foot pedal, not shown, brings it down into engagement with the lower cymbal  50   b.    
     A metal disk  55 , which is connected to strike ring  61  by upwardly and outwardly inclined arms  57 , is also mounted on the sleeve  53  by means of a resilient grommet  62 , made, for example, of rubber or elastomeric material. The metal disk  55  is made out of a magnetic material, such as iron, which is attracted to the magnets. As a result of being mounted on the resilient grommet  62 , the metal disk  55  may be tilted relative to the upper cymbal  50   a.    
     A cylindrical block  58 , which of course may have any suitable shape, is fixedly mounted on the protruding upper part of the control rod  60  within the tubular support  51  and contains the magnets  59  (which may be similar to the magnets in the first embodiment) at its lower end. In the engaged position, the magnets  59  are magnetically attracted to the metal disk  55  to bring the lower surface of the block  58  into engagement with the upper surface of the metal disk to so that the upper cymbal  50   a  rises and falls with the control rod  60 , which is operated by the foot pedal (not shown). The cylindrical block and metal disk together form a clutch mechanism permitting release of the upper cymbal  50   a  from the control rod. 
     An adjustable spring  54  extends around the support  51  between the bottom of the collar  60  and the lower cymbal  50   b . The spring  54  terminates in an upper set nut  65  screwed onto the threaded sleeve  53 . The position of the set nut  65  determines the amount of spring that protrudes below the upper cymbal. 
     The spring  54  allows the drummer to adjust the force with which the top cymbal  50   a  sits on the lower cymbal  50   b  in the disengaged position. Screwing the spring  54  upward allows the spring to sit tighter on the bottom cymbal when it falls due to gravity whereas screwing it downward allows takes some of the weight of the upper cymbal  50   a  and allows it to float more on the lower cymbal  50   b.    
     In order to disengage the upper cymbal  50   a , as shown in  FIG. 2 , the drummer strikes the strike ring  61 , which tilts the disk  55  and grommet  62 , causing the disk  55  to disengage from the magnets  59  in a similar manner to the first embodiment. Then, as shown in  FIG. 3 , as a result of its memory, the grommet naturally returns to its normal untilted position and the upper cymbal  50   a  falls onto the lower cymbal  50   b  together with the disk  55  and strike ring  61 . The drummer may then strike the cymbals  50   a  and  50   b  in the closed position. 
     To re-engage the upper cymbal  50   a , the drummer depresses the foot pedal (not shown), thereby lowering the control rod  60  to bring the magnets  59  in the cylindrical block  58  once again into contact with the disk  55 . The drummer can then resume normal operation of the upper cymbal  50   a  by depressing the foot pedal. 
     As shown in  FIG. 4 , the upper cymbal  50   a  can also be dis-engaged by means of trip bar  70  striking the strike ring  61 . The trip bar  70  is mounted on the support  51  by means of clamp  71  via pivot block  72 , which allows the trip bar  70  to be pivoted out of the way. 
       FIG. 5  shows the individual parts of the locking mechanism in exploded view. 
       FIG. 6  shows a still further embodiment intended for use with the trip bar  70 . In this embodiment instead of the strike ring  61 , a pivoting arm  80  is mounted on the control rod  90  and has a hook  82 , which normally engages under a conical abutment  81  on the upper end of the sleeve  53 . When the arm  80  engages the trip bar  70 , the arm  80  pivots, disengaging the hook  82  from the abutment  81 , thus allowing the upper cymbal  50   a  to fall onto the lower cymbal  50   b.    
       FIGS. 7A to 7H  illustrate the detailed steps in the operation of the mechanism. In this embodiment, the trip bar  91  is mounted on a rubber grommet  92 , which in turn is mounted on sleeve  93  slidably mounted on the control rod  94 . Block  95  containing magnets  96  is mounted on the control rod  97  slidable within the tubular support  94 . 
     The trip bar has a central disk portion  91  that is attracted to the magnets  96  in the block  95 . When the trip bar  91  is tilted as shown in  FIG. 14   b , the magnetic attraction is no longer sufficient to hold the upper cymbal  90   a , which then falls on to the lower cymbal  90   b  as shown in  FIGS. 7   c  and  7   d.    
     The embodiment shown in  FIG. 8  shows a stationary lower cymbal  100  supported on stand (not shown) and upper cymbal  101  coupled to the control rod  102  through the locking mechanism to be described. In particular, the domed portion  103  of the upper cymbal  101  is retained by block  104  that is slidable on the control rod  102 . The block  104  is connected to a collar  105  providing mating surface  107  with recess  106  forming part of the clutch mechanism. 
     Clutch housing  108  is coupled to the control rod  102 , and moves up and down with it. The housing  108  pivots on ball  109  affixed to the control rod when the strike ring  110  is struck. 
     The lower mating surface  111  of the housing  108  contains recess magnets which normally engage magnetically with the mating surface  107  to of the collar  105  to hold the two parts together and hold the upper cymbal in the locked position so that it moves with the control rod  102 . 
     In addition a resilient member, which in this embodiment is a compression spring  112 , is mounted between the mating surfaces  107 ,  111 , with its lower end fitted into recess  106 . The spring  112  acts to tend to force the mating surfaces  107 ,  111  apart. Extra magnets are provided so that in the engaged position, the magnetic attraction overcomes the force of the springs. 
     The spring  112  may be a 15 mm spring. In an alternative embodiment, a larger spring on the exterior of the assembly may be used, for example, a spring pressing down on the dome  103  and attached directly to the control rod  102  or housing  108 . 
     When the strike ring is tilted to trip the clutch, the magnetic attraction is broken as in the other embodiments, except that the spring  112  applies a positive force to the upper cymbal urging it against the lower cymbal. 
     The description and drawings merely illustrate the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass equivalents thereof.