DE31545C - Innovation in piano mechanics - Google Patents

Description

IMPERIAL

PATENT OFFICE

PATENT LETTERING

CLASS Sl: Musical instruments.

WILHELM FISCHER in LEIPZIG. Innovation in pianino mechanisms.

Addition to patent no. 29247 of January 30, 1884.

Patented in the German Empire on October 28, 1884. Longest duration: January 29th 189g.

In the case of the No. 29247 patented pianino mechanism the disadvantage that, in view of the considerable expenditure of force that the player can exert, there is a danger that the hammer will remain in contact with the string for longer than appropriate after it has been struck. This can be remedied by letting the resistance e coincide earlier with the hammer call α , but at the expense of the delicacy or. Possibility of playing the piano.

The inconvenience caused is to be eliminated by replacing the rocker ' c of the main patent with a ^{hinged rod c 1} , Fig. respectively in a hole in the d key. Under the rod c ¹ , a screw i is provided in the latter, which is used to regulate the height of c ¹ . Usually the rod is kept straight by a spring / pulling it against a smooth pad on the fixed bar b. The choice of the lengths and proportions of the parts concerned, as well as the setting of the abutment e and the stops m ¹ m ^{2 are} made in such a way that the hammer moves with certainty up to about 5 mm in front of the string when the key is pressed, and that while, due to his lively strength and the flexibility of his resilient handle a ^l , he rushes through the space of about 5 mm, i.e. up to the string, and strikes it, the angle arm c ^{3 of} the rod c ¹ hits the stop w ² , around the articulated rod c ¹ so far that it rests against the stop m ^{1, which} is equipped with soft upholstery, shortens the joint rod and thus pulls the hammer backwards.

Any stronger pressure on the key, which is still held down, would only increase the buckling of the rod c ¹ , but no longer cause the hammer to be pressed against the string. By only letting the key rise slightly, however, the rod c ¹ stretches itself straight again by virtue of the action of the spring / and the mechanism is then ready for a new stop.

The previously explained effect of the parts <r ' ^! and m ² could also be achieved in other ways. So z. B. by attaching an inclined plane to the rod c \ which abuts against a fixed resistance when it is raised and thus causes ^{the intended buckling of c 1.}

The ability to repeat should also be used in the explained modification of the simple mechanics the main patent remains a very perfect one.

Furthermore, it has been shown that the as an essential characteristic of the under No. 29247 patented mechanics applicable resilient and

not necessarily made of wood, but under certain circumstances also made of other suitable elastic material, the hammer handle swings back and forth for a short time after it has been struck to prevent a good sound effect. This is counteracted by one DAF the hammer shank in a ^l to the limit stops string directly or indirectly into contact with a soft, resilient body läfst occur. As such a body, Fig. 1 illustrates at η a button equipped with a soft damper felt at the front, carried by the fixed rail ο and set up in some known way to adjust its distance from the hammer handle. This distance is always measured in such a way that at the moment when the hammer head touches the string, the soft felt of the button rests against the hammer handle and the disturbing vibrations of the same are destroyed.

2 and 3 show variants of the last-mentioned device. Thus, in the first figure, the soft, elastic body η is connected to the hammer handle and meets during the attack with the adjustable or non-convertible attached rail o ¹ on the mechanism frame, while in the arrangement according to FIG. 3, abutment strips such as o or o ¹ are omitted have been brought that the body η is attached to the damper lever.

Fig. 3 illustrates in c ⁴ a stiff rod, which takes the place of the rocker c of the main patent in cases where such appears applicable and is to be regarded as an extension of that. Its length depends on the height of the instrument. With regard to its connection with the key d , what was said in the same relation for FIG. 1 applies; the connection to the Hammernufs is done in a suitable manner, for. B. by means of a piece of felt glued on both sides h, FIG. 3, or by means of a joint, as can be seen for c ^{1 in FIG.}

4 illustrates a simplification relating to the articulated rod c ^1. The special, smooth pad located on the fixed bar b , Fig. 1, against which the spring I pulls the hinge rod in order to keep it straight, and which brings frictional resistance into the mechanism to be avoided, as well as which the strikers ¹ »? ² , Fig. 1, supporting bars can be ^{omitted if the hinge rod c 1 is allowed} to buckle in the opposite direction, i.e. the angle arm c ^{3 is placed} on the side facing the string, the spring / on the opposite side. And the two parts C ¹ C ^{1 of} the articulated rod so that they cannot buckle in the direction of the pull of said spring.This purpose is achieved, as can be seen from Fig. 4, by attaching a nose ρ to each part c ¹ at the point of the central one At the point where both noses touch, one wears a strip of cloth to exclude any clicking noise.The spring / is fastened in the key d.

With this device, the triggering of the hammer should not only be complete Way can be achieved, but also the entire mechanism more easily accessible, in particular the, sucked. "Schnabelluft" should be more convenient to set.

Claims (4)

Patent Claims: ι. The replacement of the rocker c of the main patent by a joint rod c \ Fig. I, which is related to the Hammernufs α and due to the buckling at BEZW. acts retracting on the hammer after the strike. 2. The effect of the buckling of c ¹ by an angle arm c ³ hitting against an adjustable stop m ² or an ^{inclined plane connected to c 1} , which hits a fixed abutment when climbing upwards. 3. The adjustably arranged soft, elastic body η in interaction BEZW. in connection with the hammer handles to eliminate disruptive vibrations of the latter. 4. The arrangement of the articulated rod c ¹ shown in Fig. 4, in which the same buckles in the direction against the string and its straightness is caused by the spring /, and the opposing lugs ρ ρ . 1 sheet of drawings.