GB2111286A - Stringed instrument chord playing - Google Patents

Abstract

A device for attachment to or attached to the finger board or neck of a stringed instrument such as a guitar for selecting chord positions includes fingers 38 each having an operative position where a finger engages a string 30 and urges it towards the finger board so that it becomes blocked to select a desired note for that string and an inoperative position towards which the finger is normally biased, electromagnetic means 70 for urging a finger towards its operative position to overcome bias, selector switches for selectively operating particular electromagnetic means according to the chord required to urge selected fingers towards their operative positions, and means 56 for physically engaging selected fingers urged towards their operative positions and mechanically locking them in their operative positions and pressing them in their operative positions against the associated strings to select the desired notes for the chosen chord. Such a device enables even someone unfamiliar with a guitar to play chords. <IMAGE>

Description

SPECIFICATION Improvements in and relating to chord playing This invention relates to the playing of stringed instruments such as a guitar. In particular, the invention relates to a device to enable a user to select chords for a guitar.

A great deal of skill and practice is required for competence at playing stringed instruments. In the case of a guitar, the finger board is provided with a number of upstanding ridges known as frets to enable the player to define precise notes by pressing strings down against these. Despite this, however, skilful fingering is still required to select chords. Therefore, although a guitar is ideal for amateur use, a beginner cannot immediately use a guitar to accompany signing or the like.

It is therefore an object of this invention to provide a device which can select chord positions on stringed instruments such as guitars.

According to the invention there is provided a device for attachment to or attached to the finger board or neck of a stringed instrument such as a guitar for selecting chord positions, the device including fingers having an operative position where a finger engages a string and urges it towards the finger board so that it becomes blocked to select a desired note for that string and an inoperative position towards which the finger is normally biased, electromagnetic means for urging a finger towards its operative position to overcome bias, selector switches for selectively operating particular electromagnetic means according to the chord required to urge selected fingers towards their operative positions, and means for physically engaging selected fingers urged towards their operative positions and mechanically locking them in their operative positions and pressing them in their operative positions against the associated strings to select the desired notes for the chosen chord.

With such a device it is possible even for a beginner to select and then strum chords without difficulty.

The selector switches are preferably in the form of a simple keyboard or a row or rows of switch buttons so that when one key or button is depressed the appropriate electromagnetic means are actuated. Preferably the keyboard or row or rows of buttons are positioned on the top of the device such that continued pressure on them after their actuation moves them and their mounting means down towards the finger board to provide the required physical engagement of the selected fingers with the strings.

The fingers are arranged and positioned so that in their operative positions there is one for each string in each position along each string where that string may be required to be blocked for playing selected chords. In a preferred embodiment, there are three row of fingers with fix fingers in each row to enable all six strings to be blocked at any of the first three frets. As an alternative, such a device can be provided with mounting means which enable it to be moved so that the fingers instead block the strings at the second, third and fourth frets to increase the range of chords which can be selected. The resulting chords may not use standard manual fingering positions since the limitations of manual fingering do not apply here.

In such a device it is possible to select the following major and minor chords: l st Position covering 2nd Position covering 1st, 2nd s 3rd frets 2nd, 3rd } 4th frets Major chords Minor chords Major chords Minor chords Bb* G B F* D Gb Eb C A Db Bb G E Ab F B7 B7 Eb C7 A* F7 Bb G7 E* G#7 F D7 B C7 Although it is preferred to provide enough fingers to enable all normal major and minor chords to be selected, this is not essential. Instead it may be sufficient to provide the most commonly used major chords, namely those marked * above.

The device of the invention can, of course, be arranged by appropriate selection of the operation of the electromagnetic means to select any major or minor ninth, seventh or sixth chord, seventh augmented fifth chord, seventh diminished fifth chord and so on. Equally, the device can be designed to select full chords, i.e. chords where all six strings are used, or half chords, i.e. those where four strings are used.

The fingers can be biased towards their inoperative positions magnetically. By way of example, the fingers can be provided with small permanent magnets which in the non-energised condition of the electromagnets are attracted to the cores of the electromagnets. When an electromagnet is energised, however, the magnet of the associated finger can then be repelled so causing the finger to move towards its operative position. In this way, only relatively small powered electromagnets are required and so they can be powered from small storage batteries.

Once moved towards its operative position, the finger is physically engaged and trapped in that operative position whilst force applied manually by the user pushes the end of the finger against the string and down against the finger board to block that string at the desired fret.

The device preferably has physical trapping means to lock the fingers in their operative position, the device having a portion thereafter movable towards the finger board whilst the fingers are locked to cause those fingers in their operative positions to engage the strings. Preferably, also, the trapping means lock those fingers still in their inoperative positions in that inoperative position.

Preferably, the fingers are pivotally mounted near the opposite end from that designed to engage the string, the fingers hanging downwardly towards the finger board when in their operative position.

The trapping means can comprise an abutment plate resiliently mounted relative the fingers and which can be pressed against the end of the finger away from its end to engage the strings, to block the end of that finger, that end preferably having a cross piece extending out from it in the form of a T, to prevent the finger moving between its operative and inoperative positions, that abutment plate and the finger when trapped being further movable towards the finger board to bring the ends of the fingers in their operative positions into engagement with the strings.

According to one embodiment of the invention the device has a hinged top which is arranged to be pressed and hinged downwardly about an axis parallel to the strings when a chord is selected, the top having means for abutting a pair of hinged plates which in turn have fingers (preferably two) engaging an abutment plate which locks the chosen fingers in their operative positions and presses them in their operative positions against the associated strings, the fingers of the hinged plate engaging the abutment plate at locations which are spaced both widthwise and lengthwise of the abutment plate.

The invention also extends to a guitar having temporarily or permanently attached to its neck or finger board a device as described above.

Examples of devices for selecting chord positions for a guitar will now be described with reference to the accompanying drawings, in which: Figure 1 is a diagram showing one form of the device mounted on a guitar; Figure 2 is a plan of that device; Figure 3 is a side view of that device; Figure 4 is an underplan view of that device; Figure 5 is a section through that device; Figures 6 to 9 are sectional diagrams through that device showing successive steps in the movement of a finger to its operative position; Figure 10 is a sectional diagram similar to Figure 8 showing retention of a finger in its nonoperative position; Figure 11 is a circuit diagram for that device showing also the various chord positions when fingers are moved to their operating positions; Figure 1 2 is a section through a modified device for selecting chord positions;; Figure 1 3 is a sectional detail taken at right angles to the section of Figure 12; and Figure 14 is a plan view of the modified device shown in Figure 12 with the top removed.

The device 10 comprises a box-like housing 12 having a hinged cover 14, the cover being hinged to the housing along a pivot line 1 6. Projecting downwardly from the housing are four feet 18 which are arranged to engage with and clamp onto the rods 20 of a frame 22. The latter comprises a pair of straps 23 which are arranged to fit around the finger board 26 (see Figure 1) of a guitar 28 with thin straps 24 positioned beneath the strings 30 and between adjacent frets 32, these strips 24 being joined at their edges to the rods 20.

To the underside of the housing 12 are pivoted eighteen fingers 38 along three pivoted lines 40, 42 and 44. As best seen in Figure 4 the fingers 38 are arranged in three groups of six and in each group of six the fingers are arranged alternately to pivot to a downward operative position from either side of the pivot line.

The housing 12 comprises an outer frame 48 and an intermediate plate 50. It is to this latter plate that the fingers 38 are pivoted. The plate is resiliently mounted relative the outer frame by means of pins 52 at the corners of the plate which guide it relative the frame and four compression springs 54 which urge the plate in an upward direction relative the frame away from the finger board. The plate can however be depressed against the resiliency of the springs.

Above the intermediate plate 50 is an upper cam plate 56 which is resiliently mounted relative the frame 48. It has projecting from its edges four pins 58 which rest on springs wires 60 supported by the frame 48. The upper cam plate can therefore be pressed down against the intermediate plate 50 against the force of these spring wires 60.

The upper cam 56 has an abutment 62 contacted by the underside of the hinged cover 14, the latter being hinged to the outer frame 48. When the cover is pressed downwardly, its underside engages the abutment and as a first step presses the upper cam plate 56 against the intermediate plate 50. Once the two have physically abutted then further pressure on the cover and further pivoting causes both plates to move downwardly relative the frame 48.

Mounted on the underside of the intermediate plate 50 are a number of electrically-operated solenoids 70. One solenoid is provided for each finger 38. In turn, each finger has attached to it a small permanent magnet 72 and in the inoperative position of the fingers as shown in Figures 6 and 10, these magnets are attracted to the magnetic core of the respective solenoid 70 so holding the finger in its inoperative position. In this position, each finger is pivoted so as to lay relatively flat or flush with the underside of the intermediate plate 50.

Referring now to Figures 6 to 9, these show the steps in actuating an individual finger 38 so that it can block one of the strings 30 of a guitar. Initially the finger is in the inoperative position shown in Figure 6. When its respective solenoid 70 is activated, the magnet 72 attached to the finger is repelled causing the finger to pivot to a more projecting position as shown in Figure 7 where the finger hangs downwardly away from the intermediate plate 50.

Each finger has at its upper end a cross piece 74, one arm 76 of which is pointed. The upper cam plate 56 has a recess 78 for each finger into which the pointed arm 76 projects when the finger is in its inoperative position as shown in Figure 6. Upstanding from the face of the upper cam plate adjacent the edge of the recess 78 is a hook 80. When the two plates are spaced apart in the inoperative position shown in Figure 6, the finger is free to pivot to the position shown in Figure 7 once its magnet 72 is repelled by the solenoid 70 and no longer attracted to it.

At this stage continued pressure on the upper cam plate 56 causes it to move downwardly to abut the lower plate 50 and the T-shaped crosspiece of the finger 74 is now engaged by the surface of the upper plate 56 around the recess 78. This engagement causes the finger to pivot to a fully downwardly projecting position. When the two plates come together in this way the finger is therefore physically locked in its operative position and projects downwardly. Further downward movement of the upper plate 56 now causes both plates and the finger 38 to move downwardly from the position shown in Figure 8 to the position shown in Figure 9 where the finger engages one of the strings 30 so defining a particular note for that string.

When the upper plate is released both plates return to their initial position shown in Figure 6 and the movement of the upper plate 56 away from the intermediate plate 50 will cause the hook 80 to engage the pointed end 76 and pivot the finger 38 back to its inoperative position as shown in Figure 6. By this stage the solenoid 70 will also have been deactivated and so the magnet 72 will cause the finger to be engaged against the core of the solenoid.

In the case of a finger which is not to be activated when the plates are moved downwardly, reference is made to Figure 10. Once the plates 50 and 56 come together, the edge of the recess 78 engages the pointed end 76 and prevents the finger 38 moving from its inoperative position. Therefore this finger is physically locked in place in addition to the biasing by the magnet 72 and so cannot accidentally move to its operative position.

If desired the ends of the fingers designed to engage the strings can be provided with a small notch to enhance trapping and engagement over a string.

In order to select a particular chord, the cover 14 is provided with a number of push buttons 84 each of which operates a respective electricai switch 86. Each push button is labelled for a particular chord and the user presses the push button which activates the appropriate solenoids required to move the desired fingers to their operative positions. When he continues to press on the push button, thereafter the cover is caused to pivot about the pivot line 1 6. This in turn causes the underside of the cover to engage the upper plate 56 so causing the plates 56 and 50 and fingers which are to be moved to their operative position to move as described in connection with Figures 6 to 9 and those which are not to be locked in their inoperative positions as described in connection with Figure 10.When push button is of course released then the cover will pivot upwardly switching off also the solenoids and releasing the fingers.

Each switch 86 actuated by one of the push buttons 84 is designed to activate certain selected solenoids 70 causing the desired fingers to be moved to their operative position and block the strings of a guitar at the appropriate place to give the desired chord. Referring to the circuit diagram shown in Figure 11, it will be seen that in series with each output line of a switch to a solenoid 70 is a diode 88 which prevents actuation of solenoids other than those linked to the particular switch 86 closed.

Power for the circuit is provided from small storage batteries 90 which are housed within the housing 12 and cover 14 although it may alternatively be powered from the mains through the small transformer.

Because the solenoids merely have to move the fingers towards their operative positions and the actual force for blocking a string is provided by manual pressure on the buttons 84 and not by the electromagnetic force of the solenoid, the solenoids can be of relatively low power consumption and so easily energised by small storage batteries.

By appropriate connections of the solenoids to particular switches, it is possible to select the appropriate strings to give any desired chord. Figure 11 shows one particular set of connections and switches. Also forming part of Figure 11 is a chart showing the six strings 30 of a guitar and the first three frets 32. Strings can be engaged with the first fret by depressing fingers in the positions I to VI (the solenoids for effecting this are referenced I to VI). For blocking a string at a second fret a finger needs to be actuated in one of the positions I to VI and again the respective solenoids are referenced I to VI. Finally for a string to be blocked at the third fret, a finger has to be actuated in positions A to F and with again the corresponding solenoids given the references A to F.To actuate the fingers in this way and to produce particular chords by closing the switches given references 101 to 11 5, the following chords shown below can be produced with the device 10 blocking the strings at the first, second and third frets or if moved so that the fingers block the strings at the second, third and fourth frets, then the alternative the chords shown below can be produced: Device 10 covering Device 10 covering 1 sot, 2nd 8 3rd frets 2nd, 3rd Et 4th frets Major chords Minor chords Major chords Minor chords Bb* G B F* D Gb Eb C A Db Bb G E Ab F D+ B7 Eb C7 A* F7 Bb G7 E* G#7 F D7 B C7 The circuit shown in Figure 11 can be provided by an integrated circuit chip.

In the device 110 shown in Figures 1 2 to 14, the intermediate plate 50 and the upper cam plate 56 are depressed when the hinged cover 14 is depressed through the intermediary of pivoted plates 112.

The latter have rounded edges 114 received in V-shaped hinge members 11 6 attached to the outer frame 48. The two plates 112 can therefore pivot about their edges 114 in the V-shaped hinged members 11 6.

As best seen in Figure 14, each plate 112 has a pair of projecting fingers 120. When these plates 112 pivot about the hinged members 11 6 to the downward position shown in broken lines in Figure 13 it is the ends of these fingers 120 which bear against the cam plate 56. In the non-depressed position of the cam plate 56 shown in full lines in Figure 13 however the plates 112 merely rest flush with one another flat on the top of the cam plate 56.

Each pivoted plate 112 is provided with an abutment 124 which has an inclined face 126 engaged by a rounded knob 128 attached to the underside of the hinged cover 14. Therefore, when the cover is depressed by hinging about the pivot line 16 the knob 128 engages the inclined face 126 and presses down on the plates 112 causing them to pivot about the hinged members 11 6 to the dotted line position shown in Figure 1 3. At the same time the opposed inclined faces 126 cause the members 112 to be forced apart slightly so that the rounded ends 114 are urged very securely into the V-shaped hinged members and so wedged and held firmly during the pivoting.

As the members 112 are pressed downwardly the ends of their fingers 120 engage the cam plate 56 and depress this firstly against the intermediate plate 50 and thereafter both plates 56 and 50 are depressed as has previously been described with the device 10.

Because there are four relatively widely spaced points at which the ends of the fingers 120 engage the plate 56, the latter is moved down very evenly even after it contacts the plate 50 irrespective of which fingers 38 have been moved to their operative positions. Thus in the case of some chords there may be a predominance of fingers in their operative positions which are say towards the left hand end of the plate 50 as viewed in Figure 14 whilst for other chords there may be a predominance of fingers in their operative positions at the right hand end. Despite this, the relatively wide spacing at which the fingers 120 engage the plate 56 ensures that this moves downwardly without substantial tilting.

Figures 12 to 14 also show, the pins 58 which project from the edge of the cam plate 56 and which rest on and are resiliently supported by the spring wires 60 which are themselves attached to the frame 48. The movement of the cam plate 56 relative the intermediate plate 50 is further guided by four screws 130 which pass through holes in the cam plate and which are fixed to upstanding from the intermediate plate 50. The two plates 50 and 56 are additionally held apart resiliently by small coiled springs 1 32 surrounding the shanks of the screws 1 30.

To resist downward premature movement of the intermediate plate 50 small leaf springs 140 are provided which are attached at one end to the outer frame 48. Their other sprung end has an inclined portion 142 which assists in holding the plate 50 in its inoperative position until the plates 50 and 56 become abutted whereupon further downward pressure on the plate 50 cams the leaf springs 140 aside and allow the plate 50 to be depressed against the action of the springs 54 (see Figure 5).

Claims (13)

Claims

1. A device for attachment to or attached to the finger board or neck of a stringed instrument such as a guitar for selecting chord positions, the device including fingers having an operative position where a finger engages a string and urges it towards the finger board so that it becomes blocked to select a desired note for that string and an inoperative position towards which the finger is normally biased, electromagnetic means for urging a finger towards its operative position to overcome bias, selector switches for selectively operating particular electromagnetic means according to the chord required to urge selected fingers towards their operative positions, and means for physically engaging selected fingers urged towards their operative positions and mechanically locking them in their operative positions and pressing them in their operative positions against the associated strings to select the desired notes for the chosen chord.

2. A device as claimed in Claim 1 in which the selector switches are in the form of a simple keyboard or a row or rows of switch buttons so that when one key or button is depressed the appropriate electromagnetic means are actuated.

3. A device as claimed in Claim 2 in which the keyboard or row or rows of buttons are positioned on the top of the device such that continued pressure on them after their actuation moves them and their mounting means down towards the finger board to provide the required physical engagement of the selected fingers with the strings.

4. A device as claimed in any preceding claim in which in their operative positions, there are three row of fingers with fix fingers in each row to enable all six strings to be blocked at any of the first three frets.

5. A device as claimed in Claim 4 in which mounting means are provided to enable the device to be moved so that the fingers instead can block the strings at the second, third and fourth frets.

6. A device as claimed in any preceding claim in which the fingers are biased towards their inoperative positions magnetically.

7. A device as claimed in Claim 6 in which the fingers are provided with small permanent magnets which in the non-energised condition of the electromagnets are attracted to the cores of the electromagnets and which, when an electromagnet is energised, are repelled so causing the finger to move towards its operative position.

8. A device as claimed in any preceding claim which has physical trapping means to lock the fingers in their operative position, the device having a portibn thereafter movable towards the finger board whilst the fingers are locked to cause those fingers in their operative positions to engage the strings.

9. A device as claimed in Claim 8 in which the physical trapping means lock those fingers still in their inoperative positions in that position.

10. A device as claimed in Claim 8 or Claim 9 in which the physical trapping means comprise an abutment plate resiliently mounted relative the fingers and which can be pressed against the end of the finger away from its end to engage the strings, to block the end of that finger to prevent the finger moving between its operative and inoperative positions, that abutment plate and the finger when trapped being further movable towards the finger board to bring the ends of the fingers in their operative positions into engagement with the strings.

11. A device as claimed in any preceding claim in which the fingers are pivotally mounted near the opposite end from that designed to engage the string in recesses in a plate, that latter plate being engaged by the abutment plate when the fingers are locked in their operative positions, and being resiliently movable towards the finger board to cause the ends of fingers in their operative positions to engage the strings, the fingers hanging downwardly towards the finger board when in their operative position.

12. A device as claimed in any preceding claim having a hinged top which is arranged to be pressed and hinged downwardly about an axis parallel to the strings when a chord is selected, the top having means for abutting a pair of hinged plates which in turn have fingers (preferably two) engaging an abutment plate which locks the chosen fingers in their operative positions and presses them in their operative positions against the associated strings, the fingers of the hinged plate engaging the abutment plate at locations which are spaced both widthwise and lengthwise of the abutment plate.

13. A device as claimed in Claim 12 in which each hinged plate has a pair of spaced fingers.

1 4. A device for selecting chord positions for a guitar, substantially as herein described with reference to the accompanying drawings.

1 5. A guitar to which a device as claimed in any preceding claim is temporarily or permanently attached.