US2726567A - Harmonica construction - Google Patents

Description

Dec. 13, 1955 W, KRAT-r 2,726,567

HARMONICA CONSTRUCTION Filed June 22, 1951 I a I i F|G.5 FIG.6

.414 f4@ 4,5 45 I I' I II |LILIIILILILILILILILI IJIJLIL ILIL/IU .I "I I /I II`II`IVIITIIIIIVII`IVIVII-IFIVIVIVII`IIUI I INVENTOR EXW/[iam jfmt ATTORNEY United States Patent O HARMONICA CONSTRUCTION William Kratt, Union, N. J.

Application June 22, 1951, Serial No. 233,009

4 Claims. (Cl. 84-377) This invention relates to harmonicas and, more particularly, to a novel windbox construction particularly adapted to use in chromatic harmonicas.

The windbox of a harmonica is divided into compartments each laterally aligned with an opening in the mouth-piece. air over the two reeds associated with each mouth-piece opening, one reed being operated by blowing air through the opening and the other by drawing air therethrough. The reeds are secured to a reed plate, and a simple harmonica includes a single reed plate overlying one face of the windbox and forming a wall for the reed compartment.

The harmonica is completed by securing a bell or cover over the reed plate and, generally, a separate mouth-piece along the playing edge of the harmonica.

In the case of a chromatic harmonica, the windbox compartments are subdivided by a partition extending parallel to the windbox faces and substantiallymidway therebetween. This partition, in effect, provides a double set of compartments, and the mouth-piece has a double row of openings, each aligned with a compartment.

Two reed plates are provided, the reeds of one differing by a half-tone from the reeds of the other, By the use of a movable slide between the mouth-piece and the windbozr edge, either row of mouth-piece openings can be selectively blocked and the other row simultaneously fully opened. Sharps or iiats for the notes of one row of openings can be played by moving the slide to a position blocking the main scale and opening the half-tone-diierence scale.

As heretofore constructed, the windboxes have been formed by sawing, grinding, routing or otherwise removing material from a block of wood or plastic to provide the compartments and their separating partitions. This operation has been relatively expensive to perform, particularly in the case of double windboxes for chromatic harmonicas.

Additional complications in windbox formation have been introduced by the practice of` subdividing each compartment with a secondary partition having a bevelled forward edge to direct the blown air more effectively against the blow reed. This provides more effective use of the air when blowing a note, while not interfering with the efficient concentration of air over the draw reed when air is drawn outwardly through the mouthpiece.

However, such subdividing of the compartments necessitates extreme care in manufacture due to the close spacing involved and the relative thinness ofthe secondary partitions. Furthermore, the bevelling of the forward edges of the secondary partitions necessitates very ne and conscientious workmanship.

Due to its easier workability, the windbox is usually formed from a rectangular wood block of the requisite overall dimensions, the wood being cheaper, and easier and less expensive to process thanY a suitable plastic. However, the change in dimensions of the wood with changing weather conditions, and when moist during These compartments serve to direct the 2,726,567 Patented Dec. 13, 1955 ICC ' playing of the harmonica, detracts considerably from the accuracy of tuning of the harmonica.

The present invention is directed to a novel windbox construction in which the foregoing diti'iculties in manufacture are obviated, and which is less expensive to construct and much less sensitive to changes in humidity and ambient moisture content. The new windbox is particularly adapted to chromatic or double row harmonicas, but its principles of construction are equally applicable to single row simple harmonicas.

More specifically, the invention windbox is a composite structure involving a block, of essentially the dimensions of the present windbox, having a three-sidedelongated recess in one edge so that the block is essentially a substantially rectangular C. The recess is substantially congruent with the portion of the block formed with the par titioned reed compartments.

The sides of the recess have a slot extending completely therealong, this slot being parallel to and substantially midway between the two faces of the block, in the case 0f a chromatic or two-scale harmonica. The slot may be lAG inch deep, or a depth of this order. This slot is intersected, at right angles, by a plurality of other slots, of the same depth and extending between the faces of the block. These latter slots are located at the same points along the block at which the main and subpartitions are usually located.

The partition structure includes a main diaphragm member arranged to seat into the longitudinal slot and has its forward edge substantially ilush with the forward edges of the block at each end of the recess. The main diaphragm member is formed with slots extending laterally thereacross from its forward edge to about its medial section, these slots being located in correspondence with the main windbox partitions.

Each main windbox partition comprises a ilat relatively thin element having a medial slot extending substantially halfway therethrough, the length of each element being equal to the width of the main diaphragm at the designed location of the partition. The main partitions are assembled with the diaphragm by intertting of the partition slots and the diaphragm slots.

To receive the sub-partitions, dividing each reed compartment into two sections, the diaphragm has a series of lateral slots extending substantially half-way therethrough from its rear edge and located intermediate the main partition slots. The sub-partitions are thin, flat elements longitudinally slotted for interfitting with the diaphragm and long enough to extend completely across the diaphragm. The forward ends of the subpartitions are sloped toward the diaphragm and the sloping edges are bevelled to direct the air into the blow reed sections.

The main and sub-partitions are assembled with the diaphragm to form a partition unit. This unit is then inserted into the block recess with the diaphragm engaging in the longitudinal slot and the partitions engaging in the cross slots. The unit thus forms, with the recessed block, a rigid composite windbox which is the full equivalent of the present windboxes while being more easily and inexpensively formed and assembled.

While any suitable materials may be used for the composite structure, it is preferred to form the block by molding a plastic material with 'the recess and slots molded therein. Also, it is preferred to make the partitions and diaphragm of metal by stamping or the like. The windbox is thus resistant to moisture absorption and not subject to rusting due to dampness.

For an understanding of the invention principles, ref erence is made to the following description of a typical embodiment thereof asv illustrated in the accompanying drawing. In the drawing:

Figs. 1 and 2 are front and end elevation views, re

spectively, of a chromatic harmonica embodying the invention.

Fig. 3 is a plan view, partly broken away, of the invention windbox.

Fig. 4 is a front elevation view of the recessed and slotted block.

Figs. 5 and 6 are transverse sectional views on the correspondingly numbered lines of Fig. 3.

Fig. 7 is a plan view of the diaphragm member.

Fig. 8 is a plan View of the assembled partition unit.

Figs. 9 and l0 are side elevation views of a main and sub-partition, respectively.

Fig. ll is a sectional view on the line 11-11 of Fig. l0.

Figs. l2 and 13 are sectional views on the correspondingly numbered lines of Fig. S.

Referring to Figs. l and 2, a typical chromatic harmonica, which may embody the invention, is illustrate-d as comprising a windbox 15 to the forward edge of which is secured a mouth-piece 16 having an upper row of openings 17 and a lower row of openings 18. Reed plates 21, 22 are secured on either face of block 15, and enclosed by bells or covers 23, 24, respectively.

In a chromatic harmonica of the illustrated type, the two reed plates 21, 22 have scales differing by a halftone from each other. Thus, when playing notes on the scale energized through the upper openings 17, half tones (Sharps and ats) of the upper scale may be played by using the lower openings 18. Selection of the upper and lower set of openings is made by means of a slide 25 operated by a knob 26.

Slide 25 is an elongated strip mounted in a suitable guide between windbox 15 and mouth-piece 16, and has an upper row of holes spaced to coincide with openings 17. A lower row of holes is also provided, and these are located intermediate the upper holes, whereby the upper row and lower row are staggered. The holes in the slide are alternated with blanks 27.

A spring arrangement (not shown) is provided to normally bias slide 25 to a position clearing openings 17 of the main scale and correspondingly blocking openings 18 of the half-tone different scale. To play a sharp or at of the main scale, the slide 25 is moved longitudinally to uncover the openings 1S and block the openings 17.

The present invention is directed to an improved construction of windbox 1S. Referring to Figs. 3 through 6, the windbox includes a substantially solid block 4), preferably molded of a suitable plastic composition material, and a partition structure generally indicated at 50. Block 4t) has an overall rectangular shape and substantially the overall dimensions of present windboxes. However, where the block would normally be machined to provide the partitions, it is completely cut out to provide a three-sided recess 41 having side walls 42, 42

and a rear longitudinal wall The recess 41 is molded during formation of block dit. The wall 43 is sloped relative to the rear edge of the block 40, as the reed compartments vary in length from one end of the windbox to the other.

During molding of block 4t?, the walls 42, 42, 43 are formed with a shallow longitudinally continuuos slot 45 parallel to the major surfaces 44, of the block, and substantially midway therebetween in Athe case of a chromatic harmonica. Slot 4S extends completely around the recess and may be, for example, 1,46 in depth.

Intersecting slot 45 at the positions usually occupied by the main and sub-partitions for the reed compartments are slots 46 in wall 43, normal to slot 45 and extending from one surface 44 to the other. The purpose of slots 45 and 46 will appear hereinafter.

Partition structure 56 includes a diaphragm 51 having substantially the shape of recess i1 but being longer than the recess. on each edge, by the depth of slot 45. Diaphragm 51 is preferably formed of metal, and has a series of slots 52 extending inwardly from its forward edge 53. Slots 52 are located at the points where the main partitions would normally be located.

A second series of slots 54 extend inwardly from the rear edge 55a of diaphragm 51, and these slots are l0- cated where the reed compartment subdividing partitions normally would be located. Both slots 52 and slots 54 may extend half-way or less across diaphragm 51.

The main partitions 56 are shown in Figs. 5, 9 and 12 as comprising at rectangular strips having lengths equal to the widths of diaphragm 51 at the respective partition locations. Each partition 56 has a slot 57 of such length that, when the partition 56 is set in a slot 52, the partition ends will coincide with the diaphragm edges.

The sub-partitions 61 are likewise each of such a length as to extend across the diaphragm at the set locations, each partition 61 fitting into a slot 54 and having a slot 62 receiving diaphragm 51. The forward edges 63 of the sub-partitions are sloped, and are bevelled on the side toward the blow reed, as indicated at 64. These bevels result in eiective direction of the breath into the blow reed sub-compartments 55 (Fig. 3), the major portion of the air thus entering these sub-compartments and only a minor portion entering the draw reed compartments 60.

To assemble the windbox, the partitions 56 and 61 are rst assembled with diaphragm 51 to form the partition unit. This unit is then inserted in recess 41 with diaphragm 51 entering slot 45, and partitions 56 and 61 entering slots 46. This engagement of the diaphragm and partitions with the slots results in a stable maintenance of the partition unit in proper compartment forming and dividing relation. The reed plates, bells, slide, and mouth-piece are then added to complete the harmonica.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles thereof, it should be understood that the invention may be otherwise embodied without departing from such principles.

What is claimed is:

l. A windbox construction comprising a solid plastic block having an elongated recess in one longitudinal edge and a reed compartment partition unit disposed in said recess, said unit including a diaphragm substantially coextensive with the recess and partitions defining the reed compartments intertted with said diaphragm, and subpartitions dividing each reed compartment into a pair of sub-compartments interfitted with said diaphragm, the recess wall having a longitudinal slot receiving said diaphragm and transverse slots receiving the ends of said partitions, said diaphragm having lateral slots uniformly spaced along each longitudinal edge and extending partly thereacross, the slots along one longitudinal edge being staggered relative to the slots along the other longitudinal edge and said partitions and sub-partitions being inserted in said slots.

2. A windbox construction comprising a solid plastic block having an elongated recess in one longitudinal edge and a reed compartment partition unit disposed in said recess, said unit including a diaphragm substantially coextensive with the recess and partitions defining the reed compartments interfitted with said diaphragm, and subpartitions dividing each reed compartment into a pair of sub-compartments intertted with said diaphragm, the recess wall having a longitudinal slot receiving said diaphragm and transverse slots receiving the ends of said partitions, said diaphragm having lateral slots uniformly spaced along each longitudinal edge and extending partly thereacross, the slots along one longitudinal edge being staggered relative to the slots along the other longitudinal edge and said partitions and sub-partitions being inserted in said slots and have medial slots receiving said diaphragm.

3. A windbox construction comprising a solid plastic block having an elongated recess in one longitudinal edge and a reed compartment partition unit disposed in said recess, said unit including a diaphragm substantially coeXtensive with the recess and partitions defining the reed compartments intertted with said diaphragm, and subpartitions dividing each reed compartment into a pair of sub-compartments intertted with said diaphragm, the recess wall having a longitudinal slot receiving said diaphragm and transverse slots receiving the ends of said partitions, said diaphragm, partitions and sub-partitions are metal strips, said diaphragm having lateral slots uniformly spaced along each longitudinal edge and extending partly thereacross, the slots along one longitudinal edge being staggered relative to the slots along the other longitudinal edge, and said partitions and sub-partitions being inserted in said slots and have medial slots receiving said diaphragm.

4. A windbox construction comprising a solid plastic block having an elongated recess in one longitudinal edge and a reed compartment partition unit disposed in said recess, said unit including a diaphragm substantially cou extensive with the recess and partitions dening the reed compartments interttted with said diaphragm, and subpartitions dividing each reed compartment into a pair of sub-compartments intertitted with said diaphragm, the recess wall having a longitudinal slot receiving said -diaphragm and transverse slots receiving the ends of said partitions, said diaphragm, partitions and sub-partitions are metal strips, said diaphragm having lateral slots uniformly spaced along each longitudinal edge and extending partly thereacross, the slots along one longitudinal edge being staggered relative to the slots along the other longitudinal edge, and said partitions and sub-partitions being inserted in said slots and have medial slots receiving said diaphragm; and the slots in said block being molded therein.

References Cited in the file of this patent UNITED STATES PATENTS 1,094,180 Weiss et al. Apr. 21, 1914 2,339,790 Magnus Ian. 25, 1944 2,467,761 Magnus Apr. 19, 1949 2,511,302 Stephenson June 13, 1950 FOREIGN PATENTS 339,327 Germany Iuly 21, 1921

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