United States Patent 3759131

The bow is equipped with a ribbon of hair strands having its outer end fixedly mounted in the bow head or tip element and its inner end mounted in a clamp with a pivotal mounting which is axially adjustable within the bow frog which is itself axially adjustable on the bow so as to suitably adjust the tension applied to the ribbon of hair, while the pivotal mounting of its inner end provides an automatic equalization of the tension at both edges of the ribbon, so as to assure a clear tone for full, broad stroke as well as off-the-string bowing on the string instrument which may be played.

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International Classes:
G10D3/16; (IPC1-7): G10D1/02
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US Patent References:
3456544MUSICAL INSTRUMENT BOW1969-07-22Glasser
2624225Musical instrument bow1953-01-06Nebel
2258998Musical instrument bow1941-10-14Nebel
1427851Bow for musical instruments1922-09-05Rigg

Primary Examiner:
Wilkinson, Richard B.
Assistant Examiner:
Franklin, Lawrence R.
What is claimed is

1. A bow for stringed instruments comprising in combination with a flexible rod having a tip element at one end thereof and an axially adjustable frog mounted at the other end thereof, (of).

2. A bow for stringed instruments as defined in claim 1 wherein

3. A bow for stringed instruments as defined in claim 1 wherein,

4. A bow for stringed instruments as defined in claim 3, wherein said clamp mounting means has an axially adjustable link to provide a suitable take-up adjustment of any excess ribbon length for a desired range of tensioning adjustment by the frog.

Normally, the mounting of the inner end of the ribbon of hair is not pivotally but rigidly mounted in the bow frog. When tension is applied to the ribbon by axial adjustment of the bow frog rigidly along the bow rod or stick, one edge of the ribbon may have more tension than the other. This is more probable in the case of replacement of the ribbon of hair strands by unskillful hands. In any case, however, it is difficult to equalize the tension distribution across the width of the ribbon in the conventional bow, and to maintain this equalization as more tension is applied by moving the customary bow frog along the bow stick, because the inner end of the ribbon is normally rigidly mounted therein, and is resticted against any lateral angular adjustment of its clamp mounting, even though in some cases rotational adjustment on the ribbon axis is provided with restrictions against free lateral pivoting thereof.

Thus, when the hair strands are replaced on any type of presently available bows, even if this is done by a professional, many of these bows are likely to have a variation in the tension at opposite edges of the ribbon, and will provide a poor quality of tone, especially when playing off-the-string with the looser edge of the ribbon.

While the prior art does disclose some axially rotational mountings for the end clamp for the bundle of hair strands in the bow frog, as shown for example in Elsmore U.S. Pat. No. 961,589, or an axially adjustable mounting thereof, as in Nebel U.S. Pat. No. 2,624,225 or in Gray U.S. Pat. No. 1,686,554, none of the prior art shows any laterally angular pivot mounting, such as presently disclosed, for equalizing the tension on both edges of the ribbon of hair strands.

The Elsmore and Gray patents provide for axial rotation to adjust the ribbon flatly on the instrument string for broad stroke playing regardless of the axial angle at which the bow stick is held, and the Nebel patent provides for rigidly axial adjustment of the frog end clamp means in a linear guide groove, but none of these pivotal or linear adjustments of the clamp means provides lateral angular adjustment in the plane of the ribbon to fully and automatically equalize the tension on both edges of the ribbon at all times, and especially under the higer tension adjustments.

The main object of this invention is to provide and maintain equalization of tension across the wdith of the ribbon of hair strands in a bow for stringed instruments.

A further object is to provide additional axial adjustment for the inner end of the ribbon which is held in a pivotally mounted clamp means in the bow frog, besides the axial adjustment which the bow frog itself provides to vary the tension on the ribbon of hair.

Other and more specific objects will appear in the following detailed description of the invention as illustrated in the accompanying drawing, wherein:

FIG. 1 shows a common form of bow for stringed instruments,

FIG. 2 is an enlarged broken sectional view thereof,

FIG. 3 is a a composite sectional view of the frog end of a bow made in accordance with the present invention, with projections of the end and plan views of the frog,

FIGS. 4 and 5 are two modifications of the head end of this bow,

FIG. 6 is a sectional view of the mortised portion of another modification of the frog, and

FIG. 7 is a plan view, partly in section, of the clamp means shown in FIG. 6.

The conventional bow for stringed instruments which is shown in FIGS. 1 and 2 comprise a stick 10 of somewhat resilient material and having a mortised tip element or head at its outer end 12, and a mortised bow frog 14 at its inner end. The frog has a grooved bottom which slidingly engages a corresponding ridge on the inner side of the gripping end of the stick, which is hollowed out to accommodate the axial movement of a threaded eyelet 26 therein during adjustment of the bow frog by turning of the knurled head 16 of the long screw 28 which is threaded through the eyelet 26, this eyelet being fixed to the bottom of the frog. The mortises in the tip element and the frog are provided with wedge plugs 20 and 22 to hold the ends 21 of the bundle of hair strands 18 firmly therein.

One of the most appreciated qualities in a bow by the artist performers is the evenness of tension across the ribbon of hair strands that can be maintained during full, broad stoke as well as off-the-string bowing of the stringed instrument, since this produces clear and smooth tones with any desired strength or mellowness. The improvements shown in FIGS. 3 to 7 illustrate some of the specific ways in which this quality can be achieved.

FIG. 3 shows how one embodiment of my invention is incorporated in the bow frog 34. The tied end 21 of the ribbon of hair 18 is inserted into box tube 30. Plate 19 is inserted behind this knotted end 21 and the slotted machine bolt 32 is turned inward through the threaded bore in the box tube wall until the pressure of the plate 19 holds the knotted end 21 securely against the wall of the box tube 30. When the knotted end 21 has been secured the set screw 31 in the wall of the box tube 30 is tightened to keep the machine bolt from turning and loosening the grip on the end of the ribbon.

The machine bolt is then pushed out of the mortise through the hole in the rear of the bow frog 34 until the threads of the machine bolt can engage the internal threads of the slotted nipple 33. The spherical shoulder on the head of the nipple 33 engages the shoulde in the outer recess of the hole, keeping the nipple from being drawn into the mortise of the frog. Turning the nipple 33 moves the end of the ribbon back and forth inside the mortise of the frog 34. The nipple 33 fits loosely in the hole allowing the device to swing freely and to automatically equalize the tension at both edges of the ribbon of hair 18.

The bow frog is now attached to the bow stick 10 by inserting the bow screw eyelet 26 into the hollow on the inside of the stick and pushing the bow screw 28 through the end of the bow stick into this hollow until the threaded bow screw 28 engages the bow screw eyelet 26.

FIG. 4 shows the embodiment in the bow head 12 of that part of my invention which secures the end of the ribbon of hair within the mortise in the bow head 12. Instead of the conventional rectangular mortise shown in FIG. 2 this device requires a round hole into which the knotted end 21 is inserted and covered with a round dowel. The dowel has a flat side which is placed on the front of the hole through which the ribbon of hair can pass. The dowel also has a slot 38 parallel to the flat side and the small wedge 40 is inserted in this slot and driven in to spread the dowel and secure the knotted end of the ribbon in the mortise.

FIG. 5 shows the embodiment of my invention in conventional bows with rectangular shaped mortises in the bow heads. A small hole is bored through the back wall of the bow head 12 into the mortise space. The knotted end 21 is placed in the mortise and covered with plate 44 which has an outward projecton to spread the hairs evenly across the top of the bow head 12 where they leave the mortise. The machine bolt 46 is inserted through the hole in the wall of the bow head 12 and the threaded nut 50 until it meets the plate 44. Turning the machine bolt 46 creates sufficient pressure to secure the knotted end 21 between the plate 44 and the forward wall of the mortise in the head 12.

FIG. 6 show the embodiment of a modification of my device for use when it is not desirable to provide for an external adjustment of the knotted end of the ribbon of hair within the frog 58. Instead of using a nipple 33 as in FIG. 3, a coupling 62 engages the thread of the machine bolt 54 and by turning the coupling on the bolt the position of the end of the ribbon can be changed within the mortise and the device will swing sufficiently to equalize the tension across the ribbon of hair 18 at all times under all axial adjustments for varying the total tension and under all angles of ribbon contact with the strings of the instrument being played.

From the foregoing it is apparent that I am able to provide an improved bow which will enable the artist to render higher quality, clear and smooth tones at all desired strength modulations and mellowness, than has heretofore been possible in the playing of stringed instruments.

The invention may be embodied in other specific forms without department from the spirt or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention not being restrictive by the foregoing description; and all obvious changes which come within the meaning and range of equivalency of the specific parts and details illustrated , are therefore intended to be embraced therein.