US2873640A

US2873640A - Striking mechanism for music instrument

Info

Publication number: US2873640A
Application number: US513061A
Authority: US
Inventors: Jacob T Kunz
Original assignee: SCHULMERICH ELECTRONICS Inc
Current assignee: SCHULMERICH ELECTRONICS Inc
Priority date: 1955-06-03
Filing date: 1955-06-03
Publication date: 1959-02-17
Anticipated expiration: 1976-02-17

Description

Feb. 17, 1959 J. T. KUNZ STRIKING MECHANISM FOR MUSIC INSTRUMENT 2 Sheets-Sheet 1 Filed June 5, 1955 @QQQQ Ira c0000 Feb. 17, 1959 J. T. KUNZ 2,873,640

STRIKING MECHANISM FOR MUSIC INSTRUMENT Filed June 3, 1955 2 Sheets-Sheet 2 WFVENTOR. JIACOB T KUNZ wfi l) ATTORNE Y5 United States Patent STRIKING MECHANISM FOR MUSIC INSTRUMENT Jacob T. Kunz, North Hills, Pa., assignor to Schulmerich Electronics, Incorporated, Sellersville, Pa., a corporation of Pennsylvania Application June 3, 1955, Serial No. 513,061

13 Claims. (Cl. 84-405) In tubular chime notes, the note usually includes a hum tone, strike tone, a major third, a first octave, the fifth above the first octave, and the second octave, as distinguished from the partials or tones in a note produced by a campaniform or cup-shaped bell. In the case of a cup-shaped bell, there is a hum tone, a strike tone, a minor third, 21 fifth, a first octave, a second octave, and certain other partials. These instruments are in the class generally known as percussion" type instruments. The present invention particularly if of use in conjunction with organ music in a church or the like. One of the problems in prior electric musical devices of the type concerned herein has been that of obtaining the proper relationship of the partials in a note as tostrength and duration after a tone generator has been struck. Such requires proper damping of the generator so that the tones decay correctly and are in proper relationship to each other.

One of the objects of the present invention is to provide a tone generator and associated striker mechanism which will produce a chime note having the proper decay characteristics.

Another object of the invention is to provide an electric musical instrument having a relatively stiff suspension which holds the rods in such a manner that they will produce the desired tones and will attenuate the lower partials.

The term note is used herein to mean the whole sound identifying to the listener the note concerned. The terms first partial or fundamental tone are used to denote the lowest vibration or partial present in the tone generator or rod. The term partial or tone refers to a single tone and not a combination of partials or tones. The term free-free rod means a rod which is suspended in such a manner that its ends are not-fixed.

In a preferred aspect of the invention, the tone generator or rod is of the free-free type, the vibrations thereof being picked up electrically by a pick-up or transducer placed in proximity to one portion of the rod, preferably adjacent one of the ends thereof. Vibrations of the rod are picked up by the transducer which produces electrical vibrations or oscillations in a suitable amplifier circuit connected therewith. Various types of pick-ups or mechanical electrical transducers can be employed, such as magnetic, and the picked up vibrations can be modified, if necessary, in the amplifier so as to attenuate undesired partials. The instrument frame may have anchoring devices or posts and each free-free rod may have suspension receiving apertures therethrough spaced inwardly from each of its ends. A flexible suspending thread may extend through each aperture in the rod and the associated anchoring means for suspending each rod. The anchoring means and the suspension receiving aperture or contact of the thread with the rod are located inwardly from the ends of the vibrator, the suspension apertures also being located inwardly relative to their respective anchor means, such providing a relatively stitf suspension for a rod which will attenuate the lower partials. Also, the length of the lower suspension in relation to position of the an chor posts and thread is proportioned so as to attenuate the first partial at least 20 decibels. The suspension is arranged so that side movement is restricted.

Preferably, an extension is located adjacent one of the ends of the rod, said extension having an aperture therethrough for receiving a damping means, or a portion against which the damping means can slidably contact the same. The extension is not necessarily at right angles to the rod and is acoustically integral therewith. In its broadest aspect, a portion of the rod may have an aperture therethrough for receiving the damping means. The rods preferably are suspended vertically and the extensions project horizontally.

The striker mechanism for each rod may consist of an electromagnet having an armature or striker plunger operable thereby, the path of travel of the plunger being substantially in line with or adjacent to the aperture in said extension or portion of the rod. A spring-like damping means, such as a Y-shaped wire-like arrangement, extends from the end of the plunger and into or through said aperture in the extension, or against a portion of the rod. The plunger in its inoperative position rests against a fixed stop, the arm or arms of the wire in this position resiliently and slidably contacting the margins of said aperture or a portion of the rod to damp vibrations in the rod. When the electromagnet is energized by operation of a key of the instrument keyboard or otherwise, the plunger will move toward the rod so that it will strike the extension or portion of the rod and set the rod into transverse vibration. At this time, the arm means of the damper are moved upwardly and away from the margins of the extension aperture so as not to exert a damping etfect upon the rod. Upon deenergization of the electromagnet, the plunger will return to its inoperative position and the flexible arms of the damping means again will come into contact with the extension to exert a damping effect on the rod, the spring-like arms slidably contacting the vibrator and yielding as the plunger returns to its inoperative position. Thus the damping action will progressively increase. The damping effect will be that which is required to produce the proper decay in the partials of the note produced in the instrument loudspeaker not obtainable when a stiff or inflexible damper is used, the tone being cut off too sharply with an inflexible damper so as not to give the proper chime note.

In the event that it is desirable to further attenuate the rate of decay or damping of vibrations, an auxiliary means can be placed on the plunger in contact with the prior mentioned spring-like damping means. In a preferred form, this may be a plastic material, such as thermoplastic vinyl resins or the like. For example, a tube may be used connecting the damper with the striker.

These and other objects, advantages and features will become apparent from the following description and drawings, which are merely exemplary.

In the drawings:

Fig. 1 is a front view of the tone generator assembly of the instrument, some parts thereof being shown schematically in the interests of clarity.

Fig. 2 is a fragmentary enlarged elevation of two of the tone generators of Fig. 1.

Fig. 3 is a side view looking from the right in Fig. 2.

Fig. 4 is an enlarged sectional view taken in a direction 44 of Fig. 3.

Fig. is a block diagram of one manner in which the instrument can be employed.

Fig. 6 is a fragmentary view of another form of the invention.

Referring to Fig. 1, frame 10 has a plurality of free free tone generators or rods 11 suspended therefrom. At the top of frame 10, magnetic pick-up means 12 can be located on block 13 opposite each rod, said magnetic pick-up means being suitably Connected to an amplifier and electrically shielded. Frame 10 and its associated parts can be suitably mounted in casing 14, said casing also carrying amplifier 15, and a loudspeaker.

In order to facilitate shipment, clamping means 16 may have thumb screws 16', 16' carried on suitable threaded studs (not shown) on frame 10. When thumb screws 16 are tightened for shipping purposes or otherwise, all of the rods 11 will be clamped thereby so as to prevent undesired movement.

Describing one of the tone generators, rod 11 (Figs. 2, 3) may have suspension receiving aperture 17 located toward its upper end and suspension receiving aperture 18 located toward its lower end. Anchoring means or

screws

19, 19 are carried on frame 10 adjacent the suspension receiving apertures. In one form, the anchor screws may have collars 20 thereon spaced from heads 21 of the anchor screw for receiving flexible suspension thread 22. It should beevident that instead of having the thread pass through aperture 17 that it could be otherwise fixed to the rod 11 for suspending the same, such as by encircling the rod. If desired, a wedge or holding piece can be inserted in the upper aperture after the thread is in place so as to hold the same in adjusted position. The screws 19 can be turned to adjust the distance between the rod and pick-up.

The lower suspension may comprise anchor means or posts 23 fixed to frame member 10 similar to anchor screws 19. Suspension thread 24 may have one end 25 fixed to left hand (Fig. 2) HIICHJI' means and may pass through aperture 18, the thread then passing around or through an aperture in the right and anchor means upwardly to end 26 of spring 27. Spring 27 is fastened at 28 to frame 10 and serves to tension the suspensions so as to hold the rod properly. It is to be noted that

apertures

17 and 18 are located inwardly relative to their anchor means 19, 23 respectively and relative to the ends of rod 11.

The clear space between anchor posts 23, 23 preferably should be approximately about the diameter of the rod plus four times the diameter of the suspension thread so as to maintain alignment. The compliance of the suspension preferably should be arranged to provide an attenuation of at least 20 decibels of the first partial. The suspension will be frequency selective and attenuate the partials inversely with their frequency. Merely by way of example, in a rod 18" long and in diameter, the lower aperture is spaced from the suspension anchor means approximately /2 so that the thread is about /6" in length. The thread as it passes through the aperture and leads downwardly will tend to take an S shape.

In a preferred form, in order to provide a surface for striking purposes, extension 29 is located at 30 at the lower end of rod 11, said connection being one which is acoustically integral with rod 11 or one in which the fit is such that there can be no relative movement therebetween. For example, the extension 29 may be press fitted onto the rod. Extensions 29 can be made the same length for all of the rods or tone generators of the instrument. Each extension may have a downwardly extending lip 31 for thepurpose of properly guiding its striker plunger as it strikes the extension 29 in the mannet to be described hereafter.

Striker mechanism 32 comprises an electromagnetic means or solenoid 33 in which striker plunger 34 is movable. Striker plunger 34 may have a conically shaped striker head 35 carried thereon, the end of plunger 34 having an aperture therein for receiving the damping device means, said aperture in plunger 34 being provided, for example, as illustrated in Fig. 4. In this form, the aperture is formed by hollow ferrule or tube 37A, end 36 of stem 37 being reduced in size and said ferrule 37A or other similar arrangement pressed thereon. The other end of tube 37A is turned over or flanged as at 38 and striker head 35 is carried thereby. Stop washer or means 39 of a resilient material such as felt may be mounted on bracket 40, bracket 40 in turn being attached to frame 10 by means of screw means 41. If desired, there may be a slot (not shown) located in the upstanding arm 42 of the bracket so that the bracket can be vertically adjustable onframe 10.

The damping means in the preferred form may comprise a spring-like arrangement 43 having wire-like arms 44 extending upwardly from the plunger 34, said damping means being Y-shaped and having its base 45 frictionally held in the aperture in the end of plunger 34 or within tube 37A. The spring-like damping means 44 may be made from a single length of wire, such as pianowire. Arms 44 of the damping means extend upwardly and are arranged to extend into aperture 46 of extension 29. When the striker plunger 34 is in its lowermost or deenergized position, it will be positioned vertically by stop 39 and arms 44 of the damping means will be yieldably in contact with the margins of aperture 46.

In a preferred aspect, a further increase of decay or damping may be obtained by utilizing an auxiliary damping device for the main damping means which can take the form of a plastic tube 45 inserted into the aperture of plunger 34 so that a portion of the primary damping means will be in contact therewith. It can be theorized that arms 44 or other portions of the spring-like damping means 43 will be engaged by the auxiliary member to further dampen the vibrations of the rod, the auxiliary member not normally contacting extension 29. In place of the plastic tube, a thin plastic thread can be doubled up and inserted into the aperture in the end of striker plunger 34. Merely for example, nylon, Vinylite, polyvinylidene chloride, or other similar plastic can be used. When the auxiliary damping means is employed, it is possible to use a thinner wire than is used when only the spring-like damping means is employed.

In a further form, a spring-like damping means 50, (Fig. 6) can extend above a portion 51 of the rod, the damping means 50 being carried by striker plunger 52 in a manner similar to that seen in Fig. 4.

Lip 31'on extension 29 provides a means for guiding the engagement of conical-shaped head 35 as it hits a rod to set it into vibration. Thus, a striker plunger will consistently hit an extension or portion 29 in the same place and in the same direction. The lip also will serve to provide a means of better setting up transverse vibrations in a rod in order to obtain the low partials in their proper relationship.

In order to tune the rods, weights or masses 47 can be placed thereon at proper locations relative to the nodes and anti nodes thereof. In general, it is desirable to move the hum and third tones of an untuned rod the most, so that heavy weights can be placed, it needed, near the anti-nodes thereof. Merely by way of example, the weights illustrated may have longitudinal slots so that a suitable tool can have its ends inserted into said slots so as to spread the weight and move it transversely along the rod in the tuning process.

It is to be understood that different features of the invention can be used for various purposes and that details of construction can be varied without departing from the spirit of the invention except as defined in the appended claims.

What is claimed is:

1. In a strike:- and damping mechanism for an electric music instrument, the combination comprising a bar vibrator having a portion ada ted to be struck, a striker plunger adjacent said portion normally resting against a stop, an electromagnetic means for moving said striker plunger into contact with said portion when energized, and spring-like damping means extending from said plunger toward said portion, said damping means being in slidable contact with said portion when said plunger is in a deenergized position and away from said portion and is freed from said portion when said plunger is moved toward said portion upon energization of said electromagnetic means, said damping means progressively increasing damping action as it slidably engages said vibrator.

2. In a striker and damping mechanism for an electric music instrument, the combination comprising a bar vibrator having a portion with an aperture therein, a striker plunger adjacent said aperture, an electromagnetic means for moving said striker plunger into contact with said portion when energized, and spring-like damping means extending from said plunger into said aperture, said damping means being slidably in contact with said portion when said plunger is in a deenergized position and is freed from said portion when said plunger is moved toward said portion upon energization of said electromagnetic means, said damping means progressively increasing damping action upon said rod as it slidably engages it.

3. In a striker and damping mechanism for an electric music instrument, the combination comprising a bar vibrator having an extending portion with an aperture therein, a striker plunger below said portion for striking the same to produce vibrations in said vibrator, an electromagnetic means for moving said striker plunger up wardly and into contact with said portion when energized, and upstanding spring-like wire shaped damping means having diverging arms extending upwardly from said plunger into said aperture, the arms of said damping means being in contact with margins of said aperture when said plunger is in a deenergized position, energization of said electromagnetic means raising and removing said arm means from damping contact with said margins.

4. In a striker and damping mechanism for an electric music instrument, the combination comprising a vertically arranged free-free bar vibrator having a horizontally extending portion with an aperture therein, a striker plunger below said portion for striking the same to produce vibrations in said vibrator, an electromagnetic means for moving said striker plunger upwardly and into contact with said portion when energized, and up standing spring-like wire-shaped damping means having diverging arms extending upwardly from said plunger into said aperture, the arms of said damping means being in contact with margins of said aperture when said plunger is in a deenergized position, energization of said electromagnetic means raising and removing said arm means from damping contact with said margins.

5. In a striker and damping mechanism for an electric music instrument, the combination comprising a bar vibrator having a portion adapted to be struck, a striker plunger adjacent said portion and normally resting against a stop, an electromagnetic means for moving said striker plunger away from said stop into contact with said portion, spring-like primary damping means extending from said plunger toward said portion, said damping means being in slidable contact with said portion when said plunger is in a deenergized lowered position away from said portion and is freed from said portion when said plunger is moved toward said portion upon energization of said electromagnetic means, and an auxiliary damping means on said plunger contacting said damping means, said damping means progressively increasing damping action as the primary damping means slidably engages said vibrator upon returning.

6. In a striker and damping mechanism for an electric music instrument, the combination comprising a bar vibrator having a portion with an aperture therein, a

6 striker plunger below said aperture, an electromagnetic means for moving said striker plunger upwardly and into contact with said portion when energized, spring-like damping means extending upwardly from said plunger into said aperture, said damping means being in contact with said portion when said plunger is in a deenergized lowered position and is freed from said portion when said plunger is moved toward said portion upon energization of said electromagnetic means, and an auxiliary damping means on said plunger contacting said damping means.

7. In a chime or bell electric music instrument, the combination comprising a free-free bar vibrator having a portion with an aperture therein, an electric pick-up means adjacent said vibrator, amplifying means connected to said pick-up means, a loudspeaker connected to said amplifying means for producing percussion tones, a striker plunger below said aperture, a stop for said plunger upon which said plunger rests when in deenergized condition, an electromagnetic means for moving said striker plunger upwardly and into contact with said portion when energized, means for energizing said electromagnetic means and upwardly extending damping means carried by said striker plunger and extending into said aperture, said damper means being in yielding slidable contact with margins of said aperture when said plunger is in a deenergized lowered position on said stop, said damping means being removed from damping relationship with said margins and vibrator when said strike; plunger is energized.

8. In a striker and damping mechanism for an electric music instrument, the combination comprising a vertically arranged free-free bar vibrator having a horizontally extending portion with an aperture therein, said portion having a lip adjacent the end thereof, a striker plunger below said portion for striking the same to produce vibrations in said vibrator, an electromagnetic means for moving said striker plunger upwardly and into contact with said portion when energized, said lip assisting in guiding said plunger in its striking action, and upstanding springlike wire shaped damping means having diverging arms extending upwardly from said plunger into said aperture, the arms of said damping means being in contact with margins of said aperture when said plunger is in a deenergized position, energization of said electromagnetic means raising and removing said arm means from damping contact with said margins.

9. A .tone generator for an electric music instrument having a selectively operable striker, said generator comprising an elongated free-free bar vibrator, and a portion extending from said vibrator for receiving a blow from said striker to set the vibrator into vibration, said portion having a damping means receiving aperture therein and a lip for guiding said striker.

10. In a striker mechanism for an electric music in strument, a plunger means having an aperture in one end thereof, an electromagnetic means for moving said plunger, and Y-shaped wire-like damping means extending from said aperture, the base of said damping means being carried in said aperture.

11. In a striker mechanism for producing vibrations in a tone generator of an electric music instrument, a plunger means having an aperture in one end thereof, an electromagnetic means for moving said plunger, wire-like damping arm means extending from said aperture, the base of said arm means being carried in said aperture, and auxiliary damping means in said aperture contacting portions of said damping means to further damp vibrations produced 'by said striker mechanism when operated to strike said generator.

12. In a striker mechanism for producing vibrations in a tone generator of an electric music instrument, a plunger means having an aperture in one end thereof, an electromagnetic means for moving said plunger, Y-shaped wire-like damping means extending from said aperture, the base of said damping means being carried in said 7 aperture, and plastic auxiliary damping means in said aperture contacting portions of said damping means to further damp vibrations produced by said striker mechanism when operated to strike said generator.

13. In an electric musical instrument damping arrangement, the combinaticin including a vibrator, a striker, a primary damping means carried by said striker for slicla- 'bly contacting said vibrator as the striker is deenergized, said contacting progressively increasing damping action on the red as the damping means slidably contacts the vibrator as the striker returns to its deenergized position progressively increasing damping action on the vibrator, and secondary damping means contacting said .8 primary dsmping'means to accelerate damping action of said primary damping means. 7

References Cited in the file of this patent UNITED STATES PATENTS 178,717 Bluthner June 13, 1876 2,153,725 Sanders Apr. 11, 1939 2,588,295 Rowe Mar. 4, 1952 2,597,134 Stratton May 20, 1952 2,655,070 Slaymaker et a1. Oct. 13, 1953 2,703,504 Rowe Mar. 8, 1955 2,707,414 Marshall May 3, 1955 2,727,423 Meeker et a1. Dec. 20, 1955