Valve shifting mechanism for a brass instrument

[Detailed Description of the Invention]

[Industrial Application] About the piston valve change mechanism of a brass instrument, especially this invention is improved so that the sliding sound at the time of common-parts-izing of a valve guide and the switching operation of a valve may operate a piston pipe smoothly few. [Description of the Prior Art] As the piston valve change mechanism which is conventionally attached to the trumpet which is a kind of a brass instrument, and switches pipeline length to several steps and to which it made it change performance sound quantity, Two kinds, the lower spring method which has arranged the piston spring which energizes a piston pipe under this pipe, and the upper spring method arranged to the upper part, are known, and the Nakashita spring method is constituted as shown in Drawing 7. That is, 1 is a valve casing which stores piston pipe 2 and piston spring 3, A total of four holes 4 to which the tube body and extraction-and-insertion pipe of both-ends opening which omitted illustration on the drawing by being formed cylindrical are connected estrange this valve casing 1 in a peripheral direction and the direction of an axis, and it is formed, Long guide groove 6 is formed in the direction of an axis to which it shows valve guide (Spill) 5 mentioned below at an inner skin upper end part, and also bamboo hat 7 and bottom 8 are screwed on the upper-and-lower-ends opening, respectively. Does the above-mentioned piston pipe 2 have an outside diameter almost equal to the inside diameter of the above-mentioned valve casing 1? By [ a little small ] being formed cylindrical, it slides on the inside of valve casing 1 smoothly so that there may be no breath leak (it is few like [ the loss of vibration ]), Corresponding to the above-mentioned hole 4, three secret communication pipes 9 are formed in an inside, and fitting fixation of piston Shank 10 is carried out inside a upper end opening, and fitting fixation of the bottom seat 11 is carried out inside the lower end opening part. And the above-mentioned piston spring 3 is stored between this bottom seat 11 and the above-mentioned bottom 8, and the above-mentioned piston pipe 2 is energized up with this spring 3. Screw hole 13 is formed in the center of above-mentioned piston Shank 10, and screw part 15 provided in one in the lower end of piston axis 14 at this screw hole 13 is screwed in. The upper end part of piston axis 14 is projected above the above-mentioned bamboo hat 7, and the Oshigane implement 16 is attached. The above-mentioned valve guide 5 carries out regulation prevention of the rotation of the above-mentioned piston pipe 2, and permits only movement of the direction of an axis, By fitting into crevice 17 which has projected part 18 which protruded on a part of peripheral face at one, and was provided in the upper surface peripheral part of above-mentioned piston Shank 10, and being fixed with setscrew 19, the above-mentioned projected part 18 is slidably inserted in guide groove 6 of valve casing 1. 21 is Oshigane felt and 22 is piston felt. In such composition, setting maintenance of the piston pipe 2 is usually carried out by the power of piston spring 3 in the best position, If piston Shank 10 is in contact with piston felt 22 and depresses the Oshigane implement 16 with a finger in this state, in order that piston spring 3 may be resisted and piston pipe 2 may carry out the sliding descent of the inside of valve casing 1, Any one of three secret communication pipes 9 formed in the piston pipe 2 according to this amount of descent carries out correspondence coincidence with any two of four holes 4 provided in valve casing 1, and the pipeline length of a musical instrument is changed by this. [Problem(s) to be Solved by the Invention] However, since the conventional piston valve change mechanism is manufacturing each of the main component parts 1, for example, a valve casing, piston pipes 2, valve guides 5, and piston Shank 10 grades with metal, The inconvenience that a loud sliding sound jarring moreover occurs since valve casing 1 and valve guide 5 which are metal will rub if projected part 18 carries out Along up-and-down motion in guide groove 6 at the time of valve switching operation is Oh. Since it is necessary to form crevice 17 for valve guides, and screw hole 25 for setscrew 19 in piston Shank 10, there are many processing man days of piston Shank 10, since it is necessary to fix valve guide 5 not only with a manufacturing cost increasing but with setscrew 19, assembling work is also troublesome, and it is Oh. In order to have to carry out processing formation of the notch slot 26 which a part of valve guide 5 inserts also into the upper end side of piston pipe 2, manufacture of piston pipe 2 is also troublesome, and it is Oh. Drawings 8 and 9 are the conventional examples which show other mounting structures of a valve guide, respectively, The mounting structure shown in Drawing 8 fixes valve guide 5 formed in ring shape with the metal plate with piston axis 14 on piston Shank 10, The thing it was made to make piece 30 of bending provided in the peripheral face of the valve guide 5 at one insert into the guide groove of a valve casing (not shown), The mounting structure of Drawing 9 attaches valve guide 5 of a rivet form to the upper end outside peripheral surface of piston pipe 2, and it makes it make the head 5A insert into the guide groove of a valve casing (not shown). Since valve guide 5 is fixed with piston axis 14 in the former, Since valve guide 5 is still metal although it has the advantage that the setscrew for valve guides is unnecessary, If generating of the jarring metallic sound at the time of valve switching operation cannot be prevented but the upper valve guide 5 inserts screw part 15 of piston axis 14 in main hole 31, Uniquely, for a constant pine Will end reason, distance from the center of piston axis 14 to piece 30 of bending cannot use it to that from which the diameter of a piston differs, but needs to manufacture according to a model. It is necessary to form notch slot 26 for piece of bending 30 in the upper end side of piston pipe 2. On the other hand, since the latter has attached valve guide 5 of the rivet form to piston pipe 2 by press fit, a setscrew is not needed like the former, but it has the fault of being easy to transform piston pipe 2 for press fit. This valve guide 5 also has the inconvenience that the jarring metallic sound at the time of switching operation cannot be prevented, for metal. [Means for Solving the Problem] It was made that the piston valve change mechanism of a brass instrument concerning this invention should solve the conventional inconvenience which was mentioned above, In a piston valve change mechanism of a brass instrument which changed a pipeline by resisting a piston spring and depressing a piston pipe slidably fitted in into a valve casing, Piston Shank is fixed to an end of the piston pipe, and a valve guide allocated on this piston Shank is formed by a synthetic resin, A long hole is provided in that surface central part, and an engaging projection is protruded on a peripheral surface on a longitudinal direction extension of this long hole, The valve guide is fixed on piston Shank by making a guide groove of the valve casing carry out engaging of clutch of this engaging projection slidably, and inserting a lower end screw part of a piston axis in the long hole, and thrusting into a screw hole of the piston Shank. [Function] Since the valve guide was used as the cast which consists of synthetic resins in this invention, Since the hole in which mitigation prevention of the noise at the time of valve switching operation is carried out, and the screw part of a piston axis is inserted is made into the longitudinal long hole in the direction of an engaging projection, only by moving a valve guide to the longitudinal direction of a long hole, correspondence use can be carried out as it is also at the model from which the diameter of a valve differs, and common-parts-ization of a valve guide is enabled. Since it is sliding of metal and a plastic, a piston pipe may be operated smoothly. [Example] Hereinafter, this invention is explained in detail based on the example shown in a drawing. The important section sectional view of the piston valve change mechanism which requires Drawing 1 for this invention, and Drawing 2 are 1st [ The ] figure-line sectional views. To the thing of a mechanism and an identical configuration member, it is shown by the same numerals conventionally which was shown in In Fig. 7 figure~figure 9, and the explanation is omitted. In these figures, valve guide 5 consists of plastic molding, and long hole 40 is formed in the surface central part, and engaging projection 41 protrudes on a part of peripheral surface at one. The above-mentioned valve guide 5 is formed in the longitudinal direction of the above-mentioned long hole 40 for a long time, that end part is circular, the other end is formed in point thin tapered shape, and the above-mentioned engaging projection 41 is provided at the tip of this taper part 41. Therefore, the above-mentioned long hole 40 is long in the engaging projection 41 above-mentioned direction, if it sees from engaging projection 41, is located on the extension of the main axis of long hole 40, and is provided in the peripheral surface of valve guide 5. And bigger cavity 43 than this is formed in the surface of valve guide 5 in same axle by the above-mentioned long hole 40 and approximately similar figures, and projection 44 for positioning protrudes on the undersurface of the above-mentioned taper part 41. On piston Shank 10, valve guide 5 which consists of such composition is laid, and is fixed with piston axis 14. In this case, valve guide 5 is positioned by inserting the above-mentioned projection 44 for positioning in hole 45 for positioning formed in piston Shank 10. What piston axis 14 thrusts the lower end screw part 15 into screw hole 13 of piston Shank 10 for from long hole 40 via washer 47 allocated in the above-mentioned cavity 43, The above-mentioned valve guide 5 is fixed on piston Shank 10, the above-mentioned engaging projection 41 engages with guide groove 6 of valve casing 1 slidably in this fixed state, and it prevents rotation of piston pipe 2. 49 is although it is the air extraction hole formed in piston Shank 10 and being provided in the position which is not taken up with valve guide 5 in the case of this example, For example, as an air extraction hole is made to use it as the above-mentioned hole 45 for positioning and it is shown in Drawings 3 and 4 corresponding to this, of course, penetration hole 50 which arrives at even the surface of valve guide 5 may be formed in the center of a tip side of projection 44 for positioning. Since [ which was shown in Drawing 6 about other composition ] it is conventionally the same in structure and an outline, illustration is omitted. Since according to the piston valve change mechanism which consists of such composition in this way engaging projection 41 is formed by the plastic even if engaging projection 41 carries out Along up-and-down motion in guide groove 6 at the time of valve switching operation, The sliding sound which occurs between valve casings 1 which consist of metal can prevent generating of a metallic unpleasant sound small [ it is remarkable and ] conventionally as compared with the sliding sound by the metal of a mechanism. As shown in Drawings 5 and 6, the outside diameter of piston pipe 2 is large, and distance L from the center of screw hole 13 to engaging projection 41 also receives a large model, It is possible to thrust screw part 15 of piston axis 14 into the above-mentioned screw hole 13 by long hole 40, and it can use valve guide 5 in common to that from which the diameter of a piston differs. Since valve guide 5 is a cast of a plastic, it is lightweight, and when formed of the material which is rich in the upper lubricity, friction between valve casings 1 is small, and may operate piston pipe 2 smoothly. Since valve guide 5 is fixed to piston Shank 10 with piston axis 14, the setscrew for valve guides is not needed but valve guide 5 and piston axis 14 are moreover fixed simultaneously, these attachment work is also easy. In addition, since it is not necessary to carry out processing formation of the notch slot where a part of valve guide 5 engages with piston pipe 2, manufacture of piston pipe 2 is also easy and easy. [Effect of the Invention] The piston valve change mechanism of the brass instrument applied to this invention as stated above, Since the hole in which a valve guide is formed in by a synthetic resin, and a piston axis is inserted was made into the longitudinal long hole in the direction of an engaging projection, A valve guide can be used in common to that which can carry out mitigation prevention of the sliding sound of the valve casing and valve guide at the time of valve switching operation sharply and from which the diameter of a piston differs. Since sliding of a valve casing and a valve guide is sliding of metal and a plastic, the effects -- a piston pipe can be operated smoothly and certainly -- are very size.

[Brief Description of the Drawings]

The important section sectional view and Drawing 2 in which Drawing 1 shows one example of this invention are 1st [ The ] figure-line sectional views, Drawings 3 and 4 are the top view and sectional view showing other examples of a valve guide, Drawings 5 and 6 are the important section sectional view and - line sectional view at the time of applying a valve guide to what has a big diameter of a piston, The decomposition sectional view and Drawings 8 and 9 showing the conventional example of the piston valve change mechanism as which Drawing 7 adopted the lower spring method are a figure showing the conventional example of the mounting structure of a valve guide, respectively. 1 ...... A valve casing, 2 ...... A piston pipe and 3 ...... a piston spring and 5 ...... a valve guide and 6 ...... a guide groove and 10 ...... piston Shank and 13 ...... a screw hole and 14 ...... a piston axis and 15 ...... a screw part and 40 ...... a long hole and 41 ...... an engaging projection.