Corrective device for clarinets

A clarinet is provided with a post protruding above the keys adjacent the A key to limit the extent that the clarinetist can move his finger along the clarinet barrel over the convex surface of the A key and away from the F sharp key. The post provides a corrective device to assist the pupil clarinetist to locate his fingers correctly to execute the clarinet break. The post is removable so that it is essentially a teaching device alone. The post may form part of a clip attachment which can be fitted to the clarinet barrel when the pupil is under instruction.

FIELD OF THE INVENTION 
This invention relates to clarinets and is more specifically concerned with 
a corrective device for assisting a pupil to master the clarinet "break". 
STATE OF THE ART 
The clarinet covers a wide range of octaves and has numerous keys arranged 
around its barrel and distributed around its length. Some of these keys 
are very close to one another and a special technique has to be adopted if 
the player is to release the A-key and press the neighbouring F-sharp key 
correctly. The movement of the player's finger between these two positions 
is known as the clarinet break. 
The F-sharp key comprises a ring surrounding the hole in the clarinet 
barrel which is closed by the player's finger when the F-key is depressed. 
The A-key of the clarinet extends lengthwise of the barrel, and its 
playing surface is convexly curved like the underside of a spoon. The 
correct technique the player must adopt to move his finger from the spoon 
surface of the A key onto the F-sharp key, is a rolling action about the 
side edge of the finger. A sliding action between the two keys cannot be 
tolerated. 
It is necessary for a clarinetist to play the break frequently, and the 
A-key and F-sharp key are placed close to one another in consequence. A 
clarinet pupil is naturally not familiar with the precise positioning of 
his fingers on the clarinet keys, and very often, the natural position of 
his finger on the A-key convex surface is sufficiently far from the 
F-sharp key to prevent the break being executed correctly. The player's 
finger then has to slide from the A key to the F-sharp key, which quickly 
becomes a habit and impairs the player's ability to master the correct 
technique for clarinet playing. 
OBJECT OF THE INVENTION 
An object of this invention is the provision of a device to assist a 
clarinet player to master the break. 
THE INVENTION 
In accordance with one aspect of this invention a clarinet is provided 
between the convex surface of the A-key and the A-flat key, with a post 
which limits the extend that the finger of the clarinetist can be moved 
over the convex surface of the A-key in a direction away from the F-sharp 
key. 
In accordance with a second aspect of the invention a corrective device for 
fitting to a clarinet comprises a clamp for attaching to the body of the 
clarinet and which holds in place a slide-bar shaped to extend alongside 
the convex surface of the A-key and on which is an adjustably positionable 
post which is arranged to be upright alongside the convex surface of the 
A-key to limit the extent to which a player's finger can move along the 
A-key in a direction away from the F-sharp key. 
PREFERRED FEATURES OF THE INVENTION 
Preferably the clamp comprises a split part-ring which can be tightened, by 
a screw, around the clarinet barrel on the side of the F-sharp key 
opposite to the A-key. The bar suitably comprises a thin metal bar which 
extends alongside the F-sharp key, on the side opposite its hinge, to a 
position adjacent the hinge of the A-key and between the convex surface of 
the latter and the hinge of the A-flat key. The end-portion of the bar is 
preferably flattened and the post is conveniently attached to an aperture 
boss containing a grub screw and which is shaped on its underside to fit 
against the clarinet barrel. The position of the flattened surface of the 
bar is such that when the grub screw is tightened the post attached to the 
boss projects upwards about half-an-inch beyond the convex surface of the 
A-key. The clarinetist is able to position the post to suit his comfort, 
and, once positioned, it prevents him from advancing his finger further 
away from the F-sharp key than is possible for him to accomplish the 
clarinet break with the correct rolling action. 
The invention will now be described in more detail, by way of example, with 
reference to the accompanying diagrammatic drawings.

PREFERRED EMBODIMENT 
FIG. 1 shows parts of the clarinet barrel 1. The barrel has a number of 
holes distributed along its length and which are covered by valves, some 
of which are shown at 2, 3, 4 and 5. One of the holes, referenced 6, is 
open and is surrounded by a ring-shaped key 7 which controls the closure 
of the valve 3, by rotating a hinge spindle 8 to which an arm of the ring 
7 is attached. From FIG. 1 the extent of cluttering of the barrel by the 
clarinet valves is clearly apparent. 
The valve 5 is opened by the player depressing the A-key 10. The playing 
surface of this key is convexly curved in the same way as the underside of 
a spoon. The key is hinged about a trunnion 11 and it also controls 
operation of the valve 4 which is provided with an adjustable rocker 
engaging the key 10 on the opposite side of the trunnion 11 to the playing 
surface of the key. 
The movement of a player's finger from the convexspoon-like surface of the 
key 10 to the adjacent position where the ring 7 is depressed and 
simultaneously the finger covers the hole 6, is called the clarinet break. 
It can only be correctly performed by a rolling motion of the player's 
finger down the convex surface of the key 10 towards the ring 7. 
The extent that a player can roll his finger depends partly on his hand 
size and partly on the other keys which the player may have to depress 
simultaneously or next in the sequence of notes he is playing. There are 
therefore severe restrictions on the position of the finger on the surface 
of the key 10 and for this reason it is convexly curved to assist the 
player execute the correct rolling action. Unfortunately, there is a 
natural disinclination for a pupil to leave his finger resting on the 
downwardly sloping convex surface, because it is not comfortable, and 
therefore he tends to keep his finger much nearer the trunnion 11 of the 
key 10 than is possible if the correct rolling action necessary to 
accomplish the break is to be executed. 
To train a pupil to position his finger controlling the break, correctly on 
the key 10, the device shown in FIGS. 2 and 3 has been developed. The 
device comprises a part ring 20 split to provide two parts 21, 22 which 
are clamped together by tightening a screw 23 passing through a pair of 
threaded lugs 24 on respective parts of the ring. The ring is made from a 
strong metal such as stainless steel, and the two parts are so shaped that 
they can be clamped to the clarinet barrel at the position shown in FIG. 1 
without obstructing either the keys or the path of movement of the 
clarinetist's fingers when playing. 
The part 21 of the device has soldered to it a slide bar 26 the end portion 
27 of which is flattened on one side. An apertured boss 28 is slidable 
along the flattened portion 27 and a grub screw 29 is tightenable to fix 
the position of the boss 28 with respect to the end-portion 27. The 
flattened surface of the end-portion 27 is striated to assist clamping of 
the boss 28 in a chosen position by the action of tightening the grub 
screw 29. 
Soldered to the side of the boss 28 is a post 30. The underside of the boss 
28 is cut slant-wise, as shown at 31, to nest snugly against the outside 
of the clarinet barrel 1. This prevents the bar 26 behaving as a 
cantilever which could result in the post 30 exhibiting an undesirable 
resilience. 
METHOD OF USE OF PREFERRED EMBODIMENT 
The part-ring 20 of the corrective device is clamped to the clarinet barrel 
as shown in FIG. 1 which shows clearly how the part 21 is shaped to grip 
the clarinet barrel 1 between the position of the ring-key 7 and the valve 
2. A high-friction facing (not shown) is provided on the concave surfaces 
of the two parts 21 and 22 to prevent them slipping on the barrel of the 
clarinet when the screw 23 is tightened. 
The bar 26 extends axially of the clarinet when the screw 23 is tightened 
and passes alongside and beneath the position of the ring 7 so that its 
end-portion 27 lies between the hinge axis of the arm of the valve 4 and 
the adjacent convex surface of the key 10. The spacing between the key 10 
and the hinge of the valve 4 is sufficient for the boss 28 to be moved to 
any desired position along the length of the flattened-end portion 27. 
When the correct position has been found, the screw 29 is tightened and 
the post projects upwards alongside the convex surface of the key 10 to 
prevent the player's finger from advancing up the convex surface further 
than the position of the post. This post position is such that the player 
can comfortably execute the rolling action to transfer his finger from the 
key 10 to the ring 7 while simultaneously covering the hole 6. 
The corrective device is simple to attach and detach from a clarinet. It is 
also adjustable to suit the player. The post 30 automatically locates the 
player's finger at the correct position to enable him to execute the 
break. It is also adjustable to enable different players to use the 
device. The provision of the device on an instrument is not noticed by the 
player apart from the automatic effect it has in ensuring that the 
player's finger is correctly positioned to execute the break. If desired 
the post 30 may be slot-ended to receive a screwdriver and maybe screwed 
directly into a threaded socket in the boss 28. 
MODIFICATIONS OF THE INVENTION 
Although the figures illustrate a detachable device which can be fitted to 
a conventional clarinet of the prior art, it is to be understood that a 
clarinet may be made with means for enabling the post 30 to be fitted at 
the correct position when desired. For example, although not illustrated, 
it will be appreciated that the post may be provided with a threaded end 
enabling it to be screwed into a threaded socket piece capable, 
preferably, of being slid axially to different positions along the barrel 
corresponding to the positions provided by the bar 26 in FIG. 1. For 
instance, the socket piece may be movable along an axial slot let into the 
clarinet barrel beneath the position shown for the bar 26, and provided 
with an expanding element into which a bolt can be screwed to expand the 
socket piece in the slot so that it is effectively clamped at a chosen 
position suited to the clarinetist's size of hand. The post 30 can then be 
fitted to the socket piece, when required, so that it stands up at the 
desired position. When not required the post can be accommodated in one 
end portion of the barrel slot for the socket piece and held in place by 
fitting it into one side of the socket piece which can be clamped at a 
suitable position so that the post is held in a convenient storage 
position.