US1636911A - Tempo box - Google Patents

Description

i 1,636,911 J`uly 26 1927* E. A. HUsEBY TEMPO BOX Filed May 15. 1926 Patented July 26, 1927.

UNITED STATES PATENT OFFICE;

EDMOND HUSEBYV, OF CHICAGO, ILLINOIS.

TEMPO Box.

Application filed May 15,

- boxes commonly having associated therewith a valve for effecting the rapid rerolling of the sheet, and also a. stabilizing device usually consisting of a Vvalve in the suction passage from the roll motor to 'the vacuum chest or suction pump that is` controlled by a pneumatic subjected on one side to spring action and on the opposite side to the vacuum existing in the tempo box, and operating to automatically*neutralize the variations in the pressure existing inthe system during the playing of a piece.'V

One object of my present invention is to provide a very simple, inexpensive and compact device for performing the above-noted functions. Other objects are to provide an improved automatic vacuum stabilizing de- V vice, including improved means iter adjusting the sensitiveness and responsiveness thereof, to provide an improved throttle valve mechanism, and to provide an improved reroll valve. OtherI objects and attendant advantages of the invention will be apparent to persons skilled inthe art as the i same becomes better understood by reference to the following-detailed description, taken in connection with the accompanying drawings wherein I have illustrated one practical and approved embodiment of the invention, and in whichw Fig. `1 is a vertical longitudinal section,l

taken on the line 1-1 of Fig; 2;

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1;

Fig. 3. is a vertical longitudinal section through the bottom Wall of thc box taken on the line 8.-3 of Fig. 2; and F'g. 4 is a vertical transverse section taken `on the line 1r-f4 of Fig. 2.

Referring to the` drawings, the tempo box shown therein is a hollow rectangular Wooden structure, comprising a relatively thick bottom Wall 10, side walls 11, end' Walls 12,`and a top Wall or cover 13' detachably mounted on the upper edges of the side 1 and end Wallsas by screws ltand rendered f air-tight bysuitable gasket 15.

In and rsubstantially centrally ot the bot- I tom wall lOfis formed a longitudinal duct 19213.y Serial No. 109,294.

16 that at its inner end opens into the interior ot the box through a. port 17 and at its outer end communicates with an elbow nipple 18, which latter is connected bythe usual rubber tubing to the vacuum chest in i Which a partial vacuum isconstantly maintained lthrough the action of exhaustersor a suction pump. Surrounding the port 17 is an yannular Washer 19 of leather or like material constituting a valve seat.

In one side of the bottom Wall 10, parallel With the duct 16,l is formed a round bore 20 in which is tightly fitted a thin sheet-metal tube 21, one end ot which projects ythrough one of the end Walls 12 in the form ofza nipple 21, to Which is connected a tube leading y to the music roll motor.

In theY upper portion of the. bottom yWall ot the boxv directly over the hole 20 is formed an oblong slot 22; and theportion wherein the plunger valve is 'fully retracted,`

the tapered port 23 is wholly uncovered and the fullv strength ofthe suction is exerted through the nipple 18, duct- 16, port 17, port 23, tube 21 and nipple 21 upon the music roll motor. Vhen the plunger 24: is pushed. inwardly to partially closey the port 23,.the

flow passage is correspondingly throttled, and the speed of ythe music roll motor reduced, in a manner Well understood in devices oi this character.

The pressure stabilizing device in this case comprisesy a pneumatic Within the tempo box, the movable side ot which carries a valve that serves to more or less throttle the port 17. Heretofore, so far as I am aware, in pressure-stabilizing devices of this type the valve-carrying leaf of the pneumatic has been actuated in valve-closing direction by a spring, and in valve-opening direction by the suction existing Within the box. K4My present invention reverses these opposing iniiuences byan improved construction which also permits both a rough, and a tine adjustment of the sensitiveness Voi: the stabilizing pneumatic. Attached to the. under side of the cover-plate 13 "is a tapered wooden block 26 forming the fixed side of the stabilizing pneumatic, to which is connected, through the usual bellows cloth, the hinged or movable side 27. Attached to and projecting forwardly of the swinging end of the side 27 is a finger 28 in which is anchored the lower end of a pull spring 29 that is housed in a tube 30 mounted in the cover-plate 13. The upper end of the s )ring 29 is attached to a cap screw 30 tlireaded through a tapped aperture in the upper end of the tube 30 and equipped .with a lock nut 31 for securing it in set position. Maiiifestly, the pull of the spring 29 tends to maintain the stabilizin pneumatic in collapsed position against tliie opposing pull of the suction within the box, with a strength dependent upon the adjustment of the spring 29. On

the under side of `the movable leaf 27 of the manifestly acting to more. or less throttle the port 17 accordingly as the stabilizing pneumatic is expanded by the vacuum or collapsed bythe spring 29.

The spring 29 having been roughly adjusted toa strength adequate to afford approximately the normal or desired pressure inthe vacuum chamber, the sensitiveness of the ueumatic may be more finely adjusted by die device shown in Fig. l, comprising an atmospheric duct to the interior of the pneumatic that is controlled by a finely regulable device such as a needle valve. This.

device, in the form herein shown, consists of a short tube 34C mounted in the coverplate 15 with its lower end in register with a hole 35 formed through the block 26 and o ning into the interior of the pneumatic.

e tube 34 is formed with an enlarged head 36 containing Ia valve seat 37, which latter in turn is more or less throttled by a needle valve 38 having screw-threaded engagement with 'the head 86 and secured in adjusted ition by a lock nut 39'. In opposite si es of the head 36 are holes 40 through which' atmospheric air, in amounts permitted by adjustment of the needle valve, can flow into the interior of the pneumatic as the latter is expanded by the pull of the suction on its under side. Manifestly, when the vent duct last described is nearly throttled, Athe vacuum in the box works not merely against the pull of the spring 29 but against a parta vacuum within the pneumatic; whereas, when the vent duct is open suliiciently to freely admit atmospheric air `to the interior of they pneumatic in response to the expanding movement of the latter, the vacuum inthe box Works only against the pull of the spring 29. By manipulating the needle valve 38 in or out, the effect of the spring 29 in opposing the vibrations of the valve 33 may be increased or diminished without adjusting the ten-sion of the spring 29 and to a finer extent than can be secured by such adjustment alone.

When the roll motor is reversed to rewind the music sheet, speed is desired, and hence it is common practice to provide a by-pass around the throttle and pressure-stabilizing valves of the box. My resent invention provides a very simple an practical device for this purpose, consisting o a plate 1 pivoted to the bottom 10 of the box at 42 and overlying and normally covering a ir of transversely aligned ports 43 and 44 ending from the ductsk 21 and 16 into the interior of the box. In the under side of the plate 41 is formed a channel 45 which is continuously in communication with the port 43 and normally out of communication with the port 44, but may be brought into communication with the latter so as to connect the two ports through the channel 45 by means of a pull rod 4'6 connected to one end of the reroll valve 41 and extending through one'of lthe end walls 12 of the box and connected to either a manual or automatic actuating device.

Mounted in the bottom Wall lOvof the box isa threaded rod 47 having on its 'upper end a felt-capped head 48 and on its lower end a knurled knob 49; this device conitliting an adjustable stop to limit the expanding movement of the stabilizing pneumatic and prevent full closing of the port 17.

From the foregoing it will be seen that by my invention I have provided in small and lcompact compass a tempo-regulating mechanism manually or automatically actuated by the plunger valve 24; au automatic pressure stabilizing device capable of fine regulation through manipulation of the needle vulve 40: and a simple and easily manipulated reioll valve. The box may, of course, be mounted at any suitable or convenient place within the pianoand readily connected up by lines of tubing to the music roll motor, the vacuum chest or suction pump, the tempo-regulating lever, and the ieroll lever.

While I have herein shown and described one practical and simple embodiment of the invention, it is manifest that the structural details may be varied without departure from the operative principles involved or sacrifice of any of the inherent benefits and advantages. Hence, I reserve all such variations, modilications and mechanical equivalents as fall within the spirit and purview of the appended claims.

I claim- 1. In a tempo regulator of the t described, the combination of a box yfdenned with top, side and end walls, and a relatively thick bottom wall formed with a pair of air ducts in and lengthwise of its bottom wall communicating with ports opening into ISI the interior of said box and with air conduits to a roll motor and a source of suction respectively, and a plungerl valve slidable in one of said ducts across the port through which said valve-containing duct communicates with the interior of said box.

Q. In a tempo regulator of the type described, the combination ot a box formed with top, side and end Walls and a relatively thick bot-tom Wall, said bottom Wall being formed with an air duct communicating at one end through a port with the interior ot said box and at its other end with an air conduit to a source of suction, and with a second air duct communicating atoneend through a slot With the interiorot said boxand at its other end With an air conduit to I a roll motor, a metal tubetorming a lining for said second air duct and having an elongated opening registering with said slot, and

a plunger valve slidable in said tube across,

the said opening.

3. In a tempo regulator ol the type described, the combination of a` box containing a vacuum chamber and -termed with air ducts in its bottom Wall communica ing with the ports opening into said vacuum chamber and with air conduits to a roll motor and a source of suction, a valve slidable in one of said ducts across the port ot said valvecontaining duct, a pressure stabilizing pneumatic suspended from the top wall of said box, and a valve on the movable side ot said pneumatic controlling the port of the other of said ducts.

4:..In a tempo regulator ofthe type described, the combination of a box containing a. vacuum chamber and formed with ports communicating With air conduits to a roll motor and a source of suctlon, a temporegulating valve slidable across one of said ports, a pressure stabilizing pneumatic suspended from thevtop Wall of said box, a throttle valve on the movable side of said pneumatic .controlling the other of said ports, a spring tending to collapse said pneumatic against the pull of the suction in said vacuum chamber and thereby open said throttle valve, and an atmospheric vent to thefinterior of said pneumatic.

5. A speciiic embodiment of claim 4, Wh erein said atmospheric vent to the interior of said pneumatic is equipped with a regulating valve adapted to more or less throttle the fioiv ot' air through said vent.

6. In a tempo regulator of the type described, the combination of a box containing a vacuum chamber and formed in its bottom Wall with ports communicating With air conduits to a roll motor and a source. of suction, a tempo-regulating valve slidable across one of said ports, a pressure stabilizing pneumatic suspended from the top Wall oit said box, a throttle valve on the movable side of said pneumatic controlling the other ot' said ports, a spring housing mounted on the top Wall of said box, a pull spring connected at its loiver end to said movable side of the pneumatic and at its upper end anchored in said casing, and an atmospheric vent through said top Wall to the interior ot said pneumatic.

7. A specific embodiment of claim 6, wherein said pull spring is anchored in said spring casing through the agency of an adjusting screw mounted in the top Wall of the casing whereby the tension of the spring may be increased or reduced.

EDMOND A. HUSEBY.

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