Adjuster for string instruments

An adjuster with a frame attachable to the front end portion of an instrument tailpiece, a lever member with a base portion and a front plate portion swingably supported by the frame, a mounting portion with an adjusting screw positioned therein, an anchoring portion extending from the lever member that projects through an anchor hole to the surface side of the tailpiece to removably anchor a string of the instrument, and a swing transmitting member provided to the frame so as to be interposed between the adjusting screw and the lever member. The swing transmitting member is swingably supported by the frame and includes one or more transmitting levers extending along the string. When the adjusting screw is screwed into the mounting portion, one end of the transmitting lever is pushed down and another end pushes up the lever member, and the anchoring portion is swung to stretch the string.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to an adjuster that may be mounted on a tailpiece of a string instrument and that facilitates tuning of very small pitches.

2. Background Art

String instruments such as violins, violas, cellos, etc., have pegs for tightening and loosening strings for tuning. In addition, there may be cases in which tuning devices called “adjusters” are used in order to finely adjust very small pitches. The adjusters are used for tuning from a back end side of the strings that is an opposite side of the pegs. This kind of adjuster is specifically often used for the thinnest string (a first string in a case of a violin) and is mounted on a tailpiece that is fixed to a back end portion of a body of the string instrument. As a conventional adjuster, an adjuster of ball-end type is disclosed in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2007-513359, for example.

FIG. 6shows a tailpiece of an ordinary violin. The tailpiece6has a front end portion (right end portion inFIG. 6) for stretching four strings, and the front end portion is formed with anchor holes11for anchoring back ends of the strings. The anchor hole11is made by forming a circular hole11aat the back of a slit11bthat extends in the front-back direction. The circular hole11aallows a ball to pass therethrough. The slit11ballows the string to pass therethrough. The string has a ball that is fixed at the back end. The string is passed through the slit11bby passing the ball through the hole11afrom a surface side, and the string passed through the slit11bis stretched forward. Thus, the string is provided with tension.

FIGS. 7A and 7Bshow one of the adjuster of ball-end type. This adjuster has a frame101extending in the front-back direction. The frame101has a back end (left end inFIGS. 7A and 7B) provided with a cylindrical screw portion102. The screw portion102is formed with threads at an outer circumferential surface and at an inner circumferential surface and extends upwardly. The screw portion102is passed through the hole11afrom a back side (lower side inFIGS. 7A and 7B) of the tailpiece6, and the screw portion102projecting from the tailpiece6is screwed with a nut103. Thus, the adjuster is fixed to the tailpiece6. The frame101abuts on the back surface of the tailpiece6and has a front end portion that projects forward from a front end edge of the tailpiece6. The front end portion of the frame101supports an L-shaped lever105via a pin106so that the lever105is swingable in a direction indicated by an arrow H. The lever105has a hook portion104by which a string8is anchored with a ball200. The hook portion104is formed with a slit104athat opens upwardly so as to allow the string8to pass through. An adjusting screw107is screwed into the screw hole inside the screw portion102. The adjusting screw107abuts on a back end of the lever105, and the lever105swings according to a screwed amount of the adjusting screw107, whereby tuning is performed.

On the other hand,FIGS. 8A and 8Bshow an adjuster of another type. This tuning device is called an “adjuster of the loop-end type” and basically has the same structure as that of an adjuster of the ball-end type. That is, the adjuster has a frame111provided with a screw portion112. The screw portion112is passed through the hole11afrom the back side of the tailpiece6and is screwed with a nut113. An adjusting screw117is screwed into a screw hole inside the screw portion112and swings a lever115. The lever115is swingably supported via a pin116by the frame111and has a hook portion114. In this case, the lever115swings within the slit11b, which is different from the structure of the adjuster of ball-end type. Moreover, the hook portion114is close to the nut113, whereby there is no space for the ball. Therefore, a looped back end of the string8is anchored to the hook portion14.

In the adjuster of the ball-end type shown inFIGS. 7A and 7B, the lever105is relatively long, and the string8is tightened by pressing the back end portion of the lever105. Therefore, only a small controlling force is required, and tuning is easily performed. Nevertheless, since the hook portion104is arranged forward from the front end edge of the tailpiece6, the total length of the string8is short. For example, in a case of using the adjuster for one string, balance of musical sounds of the string with other strings is difficult to control. In addition, a backward extra string between the back end of the string8and a bridge (9binFIG. 2) has a length that is greatly different from those of the other strings. Accordingly, musical performance such as afterglow of musical sounds may be affected by the backward extra strings.

In contrast, in the adjuster of the loop-end type shown inFIGS. 8A and 8B, since the hook portion114is arranged over the anchor hole11, the length of the string8is not much different from those of the other strings. However, the lever115is relatively short, and thereby large controlling force is required. In addition, the lever115swings in a relatively small range. Accordingly, tuning is not easily performed.

In each of the adjusters of the ball-end type and the loop-end type, the lever105(115) is swung by the adjusting screw107(117) that passes through the hole11a. Since the lever is made to be pressed by the adjusting screw, a space between the lever and a body surface of the string instrument is small. Accordingly, the swing range of the lever, that is, the tuning range, is limited.

SUMMARY OF THE INVENTION

The present invention has been completed in view of the above circumstances, and an object of the present invention is to provide an adjuster that facilitates tuning and that does not greatly affect musical sounds.

The present invention provides an adjuster made so as to be mounted on a tailpiece on a surface side of a string instrument. The tailpiece has a front end portion and is formed with an anchor hole for a string. The adjuster includes a frame, a mounting portion for an adjusting screw, a lever, an anchoring portion, an adjusting screw, and a swing transmitting member. The frame is made so as to be removably fixed to the front end portion of the tailpiece with a fixing means. The mounting portion is provided to the frame in a side of the front end portion of the tailpiece. The lever is made so as to be arranged by passing through the anchor hole. The lever is supported by the frame so as to be swingable in a direction for stretching the string. The anchoring portion is provided at the lever and is made so as to project through the anchor hole to the surface side of the string instrument. The anchoring portion removably anchors a back end of the string. The adjusting screw is mounted by screwing it from the surface side of the instrument into the mounting portion of the frame. The swing transmitting member is provided to the frame so as to be interposed between the adjusting screw and the lever. The swing transmitting member swings the lever to a tightening side or a loosening side in the direction for stretching the string according to the screwed amount of the adjusting screw.

In the present invention, the swing transmitting member may swing the lever to the tightening side by screwing the adjusting screw into the mounting portion.

In addition, in the present invention, the swing transmitting member may include at least one transmitting lever that is swung by the adjusting screw.

In the present invention, the transmitting lever may have a lever portion that is directly swung by the adjusting screw, and the lever may be reversely swung with respect to the swung direction of the lever portion.

Moreover, in the present invention, the fixing means may include a retainer plate and a fixing screw member. The retainer plate is rotatably supported by the frame and retains the front end portion of the tailpiece between the retainer plate and the frame. The fixing screw member presses and fixes the retainer plate to the tailpiece.

In the present invention, the fixing screw member may be a nut and may be provided at the mounting portion so as to be coaxial with the adjusting screw.

According to the present invention, an adjuster that facilitates tuning and does not greatly affect musical sounds is provided.

PREFERRED EMBODIMENT OF THE INVENTION

An embodiment of the present invention will be described with reference to figures hereinafter.

FIG. 1shows an ordinary acoustic violin (string instrument) to which an adjuster of an embodiment can be mounted.FIG. 2is a side view of the violin in an arrow side from a line II-II inFIG. 1. The violin1includes a body2, a neck3, a finger board4, four pegs5, a tailpiece6, a chinrest7, and four strings8(a first string, a second string, a third string, and a fourth string in order from the right side inFIG. 1). The body2forms a hollow sound box. The neck3extends to a front end side (upper side inFIG. 1) of the body2and has a pegbox3aat a front end portion. The fingerboard4is fixed on a surface of the neck3. The pegs5are mounted to the pegbox3a. The tailpiece6and the chinrest7are fixed to a back end portion (lower end portion inFIG. 1) of the body2.

Each of the strings8is stretched between the peg5and the tailpiece6and is supported by an upper bridge9aand a bridge9b. The upper bridge9ais arranged at the front end portion of the neck3. The bridge9bstands between the fingerboard4and the tailpiece6on the surface side of the body2. Each of the strings8is provided with tension by winding or unwinding the peg5, whereby musical pitch is adjusted, that is, tuning is performed. The string8between the upper bridge9aand the bridge9bis called an effective string, and the string8extending from the bridge9bto the tailpiece6is called a backward extra string.

As shown inFIG. 6, the tailpiece6is formed with the four anchor holes11that have the holes11aand the slits11band are aligned according to the strings8. As shown inFIG. 6, the anchor holes11on the surface of the tailpiece6have a front side that is formed with a ridge line12. The ridge line12extends across in a front-back direction and supports the strings. The string8anchored by the anchor hole11contacts the ridge line12and is thereby supported. Therefore, more exactly, the string extending from the bridge9bto the ridge line12is used as the backward extra string.

As described above, in the violin1, the side of the peg5is a front side, and the side of the tailpiece6is a back side. The following descriptions relating to a front-back direction are based on this front-back direction of the violin1. On the other hand, as a vertical direction of a thickness direction of the body2, a side, at which the strings8are stretched, is a surface side.

(1) Structure of Adjuster

FIGS. 3A to 5Cshow an adjuster20of an embodiment.FIG. 3Ais a perspective view of the adjuster20in an assembled condition, andFIG. 3Bis a perspective view of the adjuster20in a disassembled condition.FIGS. 4A to 4Dare four orthogonal views, andFIGS. 5A to 5Care side views of the adjuster20mounted on the tailpiece6. As shown inFIGS. 3A to 5C, the adjuster20includes a frame30, an adjusting screw40, and a lever member50. The frame30extends in the front-back direction in a condition in which the adjuster20is mounted on the tailpiece6. The adjusting screw40is downwardly screwed into a front end portion of the frame30. The lever member50is swingably supported by the frame30and is controlled by the adjusting screw40.

The frame30is made by forming a strip plate into a hairpin shape, thereby having a folded portion at a front end side and plate portions31and32at right and left sides. The entireties of the plate portions31and32extend parallel with a space therebetween, and a back end side of the frame30is open. The right and left plate portions31and32are cranked to one side in a width direction (A direction side inFIG. 4A,4C, and4D) at different positions in a longitudinal direction. Therefore, a space33with a width larger than the other space is formed between the plate portions31and32. As shown inFIG. 4A, in the frame30, the right and left plate portions31and32are bent to the one side in the width direction, whereby the entirety of the back end portion is offset to the one side in the width direction. The back end portion is provided with a supporting portion37for a second lever (lever)52which will be described later.

The frame30has a front end that is formed into a cylindrical shape, and this cylindrical portion34has a top on which a cylindrical screw portion (mounting portion)35is uniformly formed. The screw portion35is formed with threads at an outer circumferential surface and an inner circumferential surface and extends upwardly. The screw portion35is made so that a fixing means70is mounted. The fixing means70includes a retainer plate71and a nut (fixing screw member)75. The retainer plate71is downwardly passed and is fitted to the screw portion35and is assembled so as to be rotatable around the screw portion35. The nut75is downwardly screwed on external threads at the outer circumferential surface of the screw portion35. The retainer plate71has an end that is formed with a retaining portion72with an inverted L-shape in a side direction. The retainer plate71is formed with a hole71athrough which the screw portion35passes.

The adjuster20is mounted on the tailpiece6by the fixing means70as follows. First, in a front side of an anchor hole11of the tailpiece6, at which a string8is to be tuned, the retainer plate71is horizontally turned, whereby the retaining portion72is positioned at the back side. In this condition, a space between the retaining portion72and the frame30is made to face the front end edge of the tailpiece6. Then, the front end portion of the tailpiece6is inserted into the space and is thereby held between the retaining portion72in the surface side and the frame30in the bottom side. The nut75is screwed so that the retainer plate71is pressed toward the tailpiece6, whereby the tailpiece6is strongly held between the retaining portion72and the frame30. Thus, the adjuster20is mounted on the tailpiece6.

The structure of the adjuster20in this mounted condition will be described hereinafter.

The screw hole inside the screw portion35is screwed by the adjusting screw40from above. The adjusting screw40has an upper end that is formed with a knob41. As the adjusting screw40is screwed into the screw portion35, the adjusting screw40downwardly penetrates the frame30. The frame30supports the lever member50so as to be swingable in the direction for stretching the string, that is, in the front-back direction. The lever member50is controlled so as to swing by the adjusting screw40. The lever member50is arranged in the back side of the adjusting screw40and includes a first lever (swing transmitting member, transmitting lever, lever portion)51and the second lever52. The first lever51is directly swung by the adjusting screw40. The second lever52is arranged in the back side of the first lever51and is reversely swung by the first lever51.

The first lever51is arranged inside the frame30, that is, arranged between the right and left plate portions31and32, and is swingably supported by a supporting portion36with a first pin61. The supporting portion36for the first lever51is provided in the middle of the frame30and downwardly protrudes. The first pin61is fixed to the right and left plate portions31and32. The first lever51is formed with a hole51athrough which the first pin61passes. The first lever51has a supporting point at the first pin61and swings in a direction indicated by an arrow B1-C1shown inFIG. 5Awith a guide of the right and left plate portions31and32.

The first lever51has a front end portion in the front side of the hole51afor the first pin61. This front end portion is positioned on an extension of the axis line of the adjusting screw40and can come into contact with the leading end of the adjusting screw40. The first lever51also has a back end portion in the back side of the first pin61. This back end portion is bent to one side and thereby is formed with an action part53at which a front end portion of the second lever52abuts. As the first lever51swings in the direction indicated by the arrow B1inFIG. 5A, the back end side including the action part53of the first lever51enters the space33between the right and left plate portions31and32. That is, the action part53does not contact the frame30and enters the space33, whereby the first lever51is swingable.

The second lever52is swingably supported by the supporting portion37with a second pin62. The supporting portion37for the second lever52is formed of the back end portions of the right and left plate portions31and32and guide parts38that upwardly project from the back end portions of the plate portions31and32. The second pin62is fixed to the right and left plate portions31and32at roots of the guide parts38. The second lever52is formed with a hole52athrough which the second pin62passes. The second lever52has a supporting point at the second pin62and swings within the frame30including the space33in a direction indicated by an arrow B2-C2shown inFIG. 5with a guide of the right and left guide parts38.

The second lever52is a plate with an approximately L-shape in the side direction and has a front plate portion54and an upper plate portion55. The front plate portion54extends forward, the upper plate portion55extends upwardly, and they have a base portion that is formed with the hole52a. The front plate portion54has a front end lower portion that can come into contact with the action part53of the first lever51.

The upper plate portion55of the second lever52has a top end that is tapered and is crooked so as to form a hook portion (anchoring portion)56. As shown inFIG. 4C, the hook portion56is once obtusely bent in the one side (A side) and is then crooked in a direction opposite to the one side. Thus, the hook portion56has an inner space that is offset to the one side of the adjusting screw40. In a condition in which the adjuster20is mounted on the tailpiece6, the upper portion including the hook portion56is passed through the hole11, whereby the upper plate portion55of the second lever52is arranged. Therefore, the hook portion56normally projects from the surface of the tailpiece6.

The hook portion56of the second lever52anchors the back end of the string8. The string8may be anchored with a ball-end (seeFIG. 7A) using a ball or with a loop-end in which the back end portion of the string8is looped. In the case of the string8with the ball-end, the ball is hooked by the back side of the hook portion56, and the string8is passed through the inside of the hook portion56. In the case of the string8with the loop-end, the loop is hooked around the hook portion56. As shown inFIGS. 4A and 4C, the string8is stretched by anchoring the back end thereof at the hook portion56, and the string8passes by the one side of the adjusting screw40. Therefore, the string8is tuned without contacting the adjusting screw40.

The string8is anchored at the hook portion56of the second lever52and is provided with tension (a direction indicated by an arrow D inFIGS. 5A to 5Cis a stretching direction of the string). Thus, the second lever52is normally biased so as to swing in the C2direction by the string8. Therefore, the front end lower portion of the front plate portion54normally presses down the action part53at the back end portion of the first lever51. Consequently, the first lever51swings in the C1direction, and the front end portion of the first lever51comes into contact with the leading end of the adjusting screw40. When the string8is stretched, such a contacting condition is maintained.

(2) Usage and Movement of Adjuster

Usage and movement of the adjuster20having the above structure in this embodiment will be described.

(2-1) Tightening of Strings

In order to tune a tone to be higher by tightening the string8with the adjuster20, as shown inFIG. 5B, the adjusting screw40is screwed so as to lower the leading end. Then, the first lever51is pressed by the adjusting screw40and swings in the B1direction, and the second lever52correspondingly reversely swings in the B2direction (tightening direction). As a result, the hook portion56swings back. In the second lever52, the upper plate portion55is positioned in the hole11aof the anchor hole11. Accordingly, the tension of the string8is increased, and the tone is shifted to be higher.

(2-2) Loosening of Strings

In order to tune a tone to be lower by loosening the string8with the adjuster20, as shown inFIG. 5C, the adjusting screw40is unscrewed and is raised. The front plate portion54of the second lever52is pulled by the stretched string8and thereby presses the action part53at the back end portion of the first lever51. Therefore, the first lever51swings in the C1direction while abutting the leading end of the adjusting screw40, and the second lever52correspondingly swings in the C2direction (loosening direction). As a result, the hook portion56swings forward. In the second lever52, the upper plate portion55enters into the slit lib from the hole11aof the anchor hole11. Accordingly, the tension of the string8is decreased, and the tone is shifted to be lower.

The adjuster20is used as described above. According to the adjuster20, the hook portion56of the second lever52moves in the front-back direction according to the screwed amount of the adjusting screw40. Therefore, tuning is finely performed, and very small pitches are adjusted.

(3) Effects of Embodiment

According to the adjuster20of one embodiment, the hook portion56is positioned over the anchor hole11. Therefore, the total length and the backward extra string length of the string8are not very different from those of other strings8which are directly anchored at the anchor holes11without using the adjuster20. Accordingly, balance of musical sounds of the string8with the other strings8is maintained, and musical effects such as the afterglow of the musical sounds are not greatly affected by the backward extra strings.

The entirety of the lever member50including the first lever51and the second lever52has a length corresponding to a length from the front side of the tailpiece6to the hole11aof the anchor hole11. Therefore, controlling force for swinging the lever member50by the adjusting screw40, that is, power necessary for rotating the adjusting screw40, can be small. Specifically, in a case of tightening the string8, the first lever51functions so as to raise the second lever52by a fulcrum function, whereby the controlling force can be small. Accordingly, tuning is easily performed.

The second lever52is swung by the adjusting screw40in a movable range E shown inFIG. 5A. The movable range E is greater than movable ranges F and G of the levers of the conventional adjusters shown inFIGS. 7B and 8B. Therefore, the tuning range is large, and this also facilitates the tuning.

As shown inFIG. 2, the tailpiece6is inclined so as to be separate from the surface of the body2toward the front direction in the side of the bridge9b.The adjusting screw40is arranged at the front side of the inclined tailpiece6. Therefore, the adjusting screw40vertically moves in a greater range compared with a structure of passing the adjusting screw40through the anchor hole11as in the conventional device. As a result, the swing amount of the lever member50corresponding to the screwed amount of the adjusting screw40is increased, whereby the tuning amount is increased. This also facilitates the tuning.

The adjuster20of this embodiment is removably fixed to the tailpiece6with the fixing means70by fixing the retainer plate71with the nut75. In order to remove the adjuster20from the tailpiece6, the nut75is loosened, and the retainer plate71is turned around the screw portion35, whereby the retaining portion72is removed from the tailpiece6. In conventional adjusters, the adjusting screw must be unscrewed from the screw portion, and also, the nut must be removed from the screw portion in order to remove the conventional adjuster from the tailpiece6. In contrast, in the adjuster of this embodiment, the adjuster is removed by loosening the nut75. Therefore, the adjuster of the present invention is easily mounted and demounted with respect to the tailpiece6.

The lever member50includes the two levers (the first and the second levers51and52), and the second lever52is assembled so as to reversely move with respect to the movement of the first lever51that is directly swung by the adjusting screw40. Therefore, only by screwing the adjusting screw40, the second lever52moves back, and the string8is tightened. That is, the string8is tightened by screwing the adjusting screw40and is loosened by unscrewing the adjusting screw40. Therefore, control feeling of the adjusting screw40corresponds to the tuning condition, whereby the adjuster20is convenient.

The adjusting screw40and the nut75are screwed to the screw portion35and are coaxially provided, whereby the adjuster can be reduced in size. According to this, in a case of mounting a second adjuster20on an adjacent string8, a space between the adjacent adjusters20is increased. Therefore, the second adjuster20is easily mounted, and the adjusting screw40thereof is easily rotated.

The hook portion56may be used for the string8with the ball-end by anchoring the string8with the ball. In addition, the hook portion56may be used for the string8with the loop-end by anchoring the loop at the back end portion of the string8. Therefore, the adjuster20can be widely used.

In the above embodiment, the first lever51forms the transmitting lever of the present invention, that is, the swing transmitting member. The number of the transmitting lever is not limited to one, and the transmitting lever may include plural levers that transmit swings to each other. As the swing transmitting member, any member may be used instead of the transmitting lever as long as the member has a means for swinging the second lever (lever)52according to the screwed amount of the adjusting screw40. For example, a gear, which is made so as to be turned forward and in reverse by the adjusting screw40, or a plurality of gear trains may be used. Alternatively, a combination of a gear and a lever may be used.