1 | <?php |
---|
2 | $seiten_id = 'pianola-funktionserklaerung'; |
---|
3 | $version = '$Id'; |
---|
4 | $titel = 'Functional explanation of the pianola'; |
---|
5 | |
---|
6 | require '../../lib/technikum29.php'; |
---|
7 | ?> |
---|
8 | <h2>Functional explanation of the pianola</h2> |
---|
9 | |
---|
10 | <div class="desc-right auto-bildbreite borderless no-copyright" title="Zum Vergrößern klicken"> |
---|
11 | <a class="popup" href="/de/geraete/pianola-funktionserklaerung/fotos/pianola-offen.jpg"><img src="/de/geraete/pianola-funktionserklaerung/fotos/thumb.pianola-offen.jpg" alt="Inside view of the pianola" width="300" height="225"></a> |
---|
12 | <p>Inside view of the pianola</p> |
---|
13 | </div> |
---|
14 | |
---|
15 | <p>The "pianola" is an automatic piano - the instrument shown in the picture on |
---|
16 | the right was built in 1915. Instruments of this type are controlled by a |
---|
17 | vacuum system that is powered by bellows operated either manually or by means |
---|
18 | of a motor. The pneumatic system of the instrument described in the following |
---|
19 | is powered by a motor.</p> |
---|
20 | |
---|
21 | |
---|
22 | <div class="desc-left auto-bildbreite borderless no-copyright" title="Zum Vergrößern klicken"> |
---|
23 | <a class="popup" href="/de/geraete/pianola-funktionserklaerung/fotos/abfuehlkamm.jpg"><img src="/de/geraete/pianola-funktionserklaerung/fotos/thumb.abfuehlkamm.jpg" alt="Pickup bar" width="268" height="109"></a> |
---|
24 | <p>Pickup bar</p> |
---|
25 | </div> |
---|
26 | |
---|
27 | <div class="desc-left auto-bildbreite borderless no-copyright" title="Zum Vergrößern klicken" style="clear: left;"> |
---|
28 | <a class="popup" href="/de/geraete/pianola-funktionserklaerung/fotos/notenrolle.jpg"><img src="/de/geraete/pianola-funktionserklaerung/fotos/thumb.notenrolle.jpg" alt="Piano roll" width="268" height="175"></a> |
---|
29 | <p>Piano roll</p> |
---|
30 | |
---|
31 | </div> |
---|
32 | <!--<div class="left-thumb" style="width: 260px;"> |
---|
33 | <img src="/de/geraete/pianola-funktionserklaerung/zoomgrafiken/rolle.png" alt="Rolle schematisch"> |
---|
34 | <p>Die ablaufende Rolle und die Abtastung rein schematisch</p> |
---|
35 | </div>--> |
---|
36 | The piano roll is a strip of paper, many meters long, with holes punched in |
---|
37 | rows. Single holes or sequences of holes represent notes. This paper strip |
---|
38 | moves over a pickup bar with 88 openings (one for each key of the piano). In |
---|
39 | addition to these, this pickup contains additional openings which are used to |
---|
40 | control the pedals, the attack and the like. |
---|
41 | |
---|
42 | |
---|
43 | </p> |
---|
44 | <div class="desc-right auto-bildbreite borderless no-copyright" title="Zum Vergrößern klicken"> |
---|
45 | <a class="popup" href="/de/geraete/pianola-funktionserklaerung/fotos/pianola-innen.jpg"><img src="/de/geraete/pianola-funktionserklaerung/fotos/thumb.pianola-innen.jpg" alt="Back view of the pianola" width="300" height="225"></a> |
---|
46 | <p>Back view of the pianola</p> |
---|
47 | </div> |
---|
48 | <p>Clearly visible in the picture of the right are the yellow colored lead tubes |
---|
49 | that connect the pickup bar with the pneumatic amplifiers. These amplifiers are |
---|
50 | called "relays" and amplify the tiny differential pressures delivered by the |
---|
51 | pickup mechanism sufficiently to actuate the keys and pedals of the piano.</p> |
---|
52 | |
---|
53 | |
---|
54 | <div class="box center" title="Zum Vergrößern klicken"> |
---|
55 | <a href="/de/geraete/pianola-funktionserklaerung/zoomgrafiken/schema-uebersicht.png"><img style="border: none;" src="/de/geraete/pianola-funktionserklaerung/zoomgrafiken/thumb.schema-uebersicht.png" alt="Schematic diagram of a single amplifier/actuator |
---|
56 | (relay) element"></a> |
---|
57 | <p class="center"> Schematic diagram of a single amplifier/actuator |
---|
58 | (relay) element |
---|
59 | (<a href="/de/geraete/pianola-funktionserklaerung/zoomgrafiken/schema-uebersicht.png">enlarge image</a>)</p> |
---|
60 | </div> |
---|
61 | |
---|
62 | |
---|
63 | <!-- |
---|
64 | Befehle zum Generieren der Thumbnails: |
---|
65 | |
---|
66 | $ for bild in *.png; do convert -verbose $bild -resize 200x150\> -size 200x150 xc:white +swap -gravity center -composite thumb.$bild; done; |
---|
67 | --> |
---|
68 | |
---|
69 | <h3 class="clear"><a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild1.png">Picture 1</a>: Quiescent state</h3> |
---|
70 | <div class="box left"> |
---|
71 | <a class="thumb" href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild1.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/thumb.Bild1.png" alt="Amplifier/actuator in quiescent state"></a> |
---|
72 | </div> |
---|
73 | |
---|
74 | <p>The schematic diagram shows one relay element. 88 of these are necessary to |
---|
75 | control all of the piano's keys. Due to their size, these 88 relays are mounted |
---|
76 | in three rows. Yellow color denotes part of the vacuum system while blue marked |
---|
77 | areas are at atmospheric pressure. </p> |
---|
78 | |
---|
79 | <h3 class="clear"><a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild2.png">Picture 2</a>: Hole in the piano roll, air enters the pickup bar</h3> |
---|
80 | <div class="box left"> |
---|
81 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild2.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/thumb.Bild2.png" alt="Schema des pneumatischen Systems während Luft einströmt"></a> |
---|
82 | </div><div class="box right"> |
---|
83 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild2.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/big.Bild2.png" alt="Ausschnitt aus dem Schema des pneumatischen Systems, während Luft einströmt"></a> |
---|
84 | </div> |
---|
85 | |
---|
86 | <p>A hole in the piano roll allows air to enter the corresponding hole in the |
---|
87 | pickup bar. A small "pillow" located under the right valve of the relay is |
---|
88 | inflated by this stream of air which in turn opens the valve. |
---|
89 | </p> |
---|
90 | |
---|
91 | |
---|
92 | <h3 class="clear"><a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild3.png">Picture 3</a>: Amplification:</h3> |
---|
93 | <div class="box left"> |
---|
94 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild3.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/thumb.Bild3.png" alt="Schema des pneumatischen Systems, erster Kolben bewegt sich"></a> |
---|
95 | </div><div class="box right"> |
---|
96 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild3.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/big.Bild3.png" alt="Vergrößerung des Verstärkungseffekts durch den Kolben"></a> |
---|
97 | </div> |
---|
98 | |
---|
99 | <p>This right valve allows air to enter the left part of the relay which is built |
---|
100 | in a similar way. Another "pillow" actuates the left valve which is much bigger |
---|
101 | than the left valve and thus allows more air to flow. These two valves in fact |
---|
102 | act like an amplifier: The small pressure difference sensed by the pickup bar |
---|
103 | controls the first (right) valve which acts as a first amplifier stage. This |
---|
104 | controls the second (left) valve which acts as a power amplifier operating the |
---|
105 | the bellow shown below the relay unit.</p> |
---|
106 | |
---|
107 | <h3 class="clear"><a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild4.png">Picture 4</a>: Contracting the bellow</h3> |
---|
108 | <div class="box left"> |
---|
109 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild4.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/thumb.Bild4.png" alt="Schema des pneumatischen Systems: Der zweite Kolben sorgt für eine weitere Verstärkung des Effektes"></a> |
---|
110 | </div><div class="box right"> |
---|
111 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild4.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/big.Bild4.png" alt="Ausschnitt aus dem Schema in der jetzigen Position"></a> |
---|
112 | </div> |
---|
113 | |
---|
114 | <p>The left valve of the relay connects the bellow located under the relay block |
---|
115 | with the evacuated part of the pneumatic system. When activated, this valve |
---|
116 | will cause the bellow to contract which in turn moves the corresponding key of |
---|
117 | the piano.</p> |
---|
118 | |
---|
119 | |
---|
120 | <h3 class="clear"><a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild5.png">Picture 5</a>: Preview of a tone</h3> |
---|
121 | <div class="box left"> |
---|
122 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild5.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/thumb.Bild5.png" alt="Schema des pneumatischen Systems: die Luft strömt aus dem Blasebalg, er zieht sich zusammen"></a> |
---|
123 | </div><div class="box right"> |
---|
124 | <a href="/de/geraete/pianola-funktionserklaerung/einzelbilder/Bild5.png"><img src="/de/geraete/pianola-funktionserklaerung/einzelbilder/big.Bild5.png" alt="Vergrößerung der Bewegung des Blasebalges"></a> |
---|
125 | </div> |
---|
126 | <p>Without additional hardware, the bellow would stay in the contracted state |
---|
127 | after being actuated once. Thus, some means are necessary to release the bellow |
---|
128 | after a note and ready the system to play the next note. If there is no hole in |
---|
129 | the piano roll following the hole which actuated the bellow, the bellow must be |
---|
130 | returned to its inflated state as quickly as possible. </p> |
---|
131 | |
---|
132 | |
---|
133 | <p>The picture on the right shows a small connection between the tube coming from |
---|
134 | the pickup strip and the vacuum system on the far right. This connection has a |
---|
135 | very small diameter so that it does not negatively affect the inrushing air |
---|
136 | current from the pickup bar when a hole is detected. If there is no hole, this |
---|
137 | connection withdraws the remaining air at atmospheric pressure from the right |
---|
138 | valve system thus closing this valve which, in turn, will close the second |
---|
139 | valve, which will eventually cause the bellow to inflate again. Now the |
---|
140 | pianola is ready to play the next note. </p> |
---|
141 | |
---|
142 | <div class="right"> |
---|
143 | <img src="/de/geraete/pianola-funktionserklaerung/entlueftung.png" alt="Die Entlüftungskammer"> |
---|
144 | </div> |
---|
145 | |
---|
146 | <p>The pianola is able to play pieces which were impossible to play for a human |
---|
147 | player. Accordingly, there are pieces composed for the pianolo exclusively |
---|
148 | (like the "Studies for Player Piano" by Conlon Nancarrow). |
---|
149 | |
---|
150 | It is impressive to see what can be done by more or less simple mechanical |
---|
151 | systems. |
---|
152 | |
---|
153 | |
---|
154 | |
---|