US2477995A

US2477995A - Shaft-positioning apparatus

Info

Publication number: US2477995A
Application number: US590890A
Authority: US
Inventors: Richard C Marholz
Original assignee: BELMONT RADIO CORP
Current assignee: BELMONT RADIO Corp
Priority date: 1945-04-28
Filing date: 1945-04-28
Publication date: 1949-08-02
Anticipated expiration: 1966-08-02

Description

1949- R. c. MARHOLZ' 2,477,995

SHAFT-POSITIONING APPARATUS Filed April 28, 1945 2 Sheets-Sheet 1 J50. 15b I INVENTOR. Md C 017L043,

BY Mk f/Wao 9- R. c. MARHO LZ 2,477,995.

SHAFT-POSITIONING APPARATUS Filed April 28, 1945 2 Sheets-Sheet 2 INVENTOR.

Patented Aug. 2, 1949 Richard C. Marnom'chiea o, 111., asslgnor to Belmont Radio Corporation, Chicago, 111., acorporation of Illinois I Application April 28, 1945, Serial No 590,890

11 Claims. (Cl. 287-52) 1 This invention relates to shaft-positioning apparatus and, while it is of general application, it is particularly suitable for positioning the shaft of the tuning apparatus of a radio-broadcast receiver, that is to a so-called mechanical tuner, and it will be described in such an application;

Heretofore there have been devised numerous mechanical tuners for radio-broadcast receivers of a wide variety of types. In general, a tuner of this type comprises a rotatable shaft, usually an extension of the shaft of the tuning condenser, and a plurality of shaft-positioning members or cams, one for each of a group of stations to which the receiver is adapted to be tuned. Each cam or member is locked to the shaft in such a pre determined angular position that, when a cam actuator is brought into engagement and pressed to the point on the cam of minimum radius, the associated condenser tunes the receiver to the station corresponding to soon cam and cam actuator.

' When initially setting up such a mechanical tuner or when resetting it to adapt it to be mechanically tuned todifierentstations, either in the same or different localities, there is presented the problem of releasing the several locking members for individual adjustments to new angular positions independently of each other. It is preferable to be able to effect this release readily from the front of a broadcast receiver cabinet and with only a moderate amount of actuating force and" that the releasing mechanism be simple" and inexpensive in construction and reliable in operation. The prior art mechanical tuners have left much to be desired in this respect.

It is an object of the invention, therefore, to provide a new and improved shaft-positioning apparatus which overcomes the above mentioned disadvantages and imitations oi the prior art apparatus of this type.

It is another object of the invention to provide a new and improved shaft-positioning apparatus including simple and inexpensive provisions tor releasably locking one or more of the shalt-positioning members in any desired relative angular position or positions.

It is a further object oil the invention to pip vide a new and imprcvedshaft-positionnig apparatus applicable to the mechanical tuners oi broacast receivers including novel provisions for releasably locking the several. shaft-positioning members from the front oi the receiver casing.

In accordance with the invention, shaft-posiitioning apparatus comprises a rotatable shaft having a recess therein and a shaft posltiontns member rotatably mounted on the shaft and at least partially coveringthe recess. The apparatus also includes means for releasably locking the; shaft to the memberin any, desired angular position, including a resilient deformable look-,- ing membervdisposed in therecess and means for deforming the locking member to engage the po sitioning member. 7 Further inaccordance with the invention, positioniug apparatus comprises a. rotatable shalt, a plurality of axially spaced shaft-positioning members rotatably mounted'on the shaft, andan elongated axially adjustable locking means including a plurality of portions individually engaging the members for locking and releasing the members with respect to the shaft. For a bctter understanding or the invention, together with other and further obiects thereof, reference is had to the icllowmg description taken in connection with the accompanying drawingswhlle its scope will be pointed out in the appended claims.

- Referring now to the drawings, Fig. 1 is a view in front elevation, Fig, 2 a bottom view,- and Fig. 3 is a view or a mechanical tuner for a broadcast receiver incorporating the shait-positionini apparatus or the invention taken on line 3-4 oi; Fig, 2; 4 is a fragmentary exploded perspective View of one of the Shaft-positioning members oi the structure or Figs. 1-3, inclusive, audits associated locking means; Figs. 5 and 6 are vertical and horizontal longitudinal sectional views 01 the releasable locking means or the structure oi Figs, 1-3, inclusive; whileFiss. 7 and a are longitudinal sectional views and cross sectional views, respectively, of a modified form of re leasable locking means suitable for embodiment inqthe mechanical tuner of Figs. 1-3, inclusive. Reierringnow more particularly to Figs. 1, 2 and 3 of the drawings, there is represented a shait-positiomng apparatus embodying the in.- vention as applied to a mechanical tuner oils radimbroadcast receiver. The tuning mechaper so, may be of any conventional type and is illustrated, by was of example, as including a pair of adjustablertuning cmdensers 1M and H mounted on a common shalt l2 forum-control, the shaft 92 being iournaled in. a U-shaped Home It. The positioning apparatus also incmdesqa hollow rotatable shalt which may constitute either anextension or the condenser shalt it or a separate shalt connected thereto in am] suit abletashicn. The shatt to is provided with .a plurality oi axially spaced circumierential receases a each having: a pair of diametrically a series of spacing washers Ila-He, inclusive,-

keyed or otherwise secured to the shaft against rotation to permit independent positioning of the several cams l5a-I5f, inclusive. Each of the hubs Mia-I61, inclusive, at least partially and. preferably completely individually covers its respective one of the recesses [4a and the apertures Mb in the shaft I4.

The positioning apparatus also includes a plurality of cam operators, such as push buttons l8ol8f, inclusive, pivotally mounted on a shaft l9 and biased out of contact with their respective cams by a series of axial springs, such as the spring I90 (Fig. 3).. The buttons l8al 8 project through apertures in the front wall of the receiver cabinet 24. The cams l8a-l8j, inclusive, are provided with actuating rollers 20o20f, inclusive, respectively, for actuating their respective cams to set the shaft [4 when locked to the cams,

and thus the condenser shaft [2, into predetero mined angular positions corresponding to the positions of the tuning condensers I and Il required to tune the receiver to the preselected broadcast stations. The shafts l4 and I9 are suitably mounted in a frame 28 secured to the frame I3 or forming an extension thereof.

The positioning apparatus also includes an elongated axially adjustable locking means including a plurality of portions individually engaging the positioning members .or cams I8a--l8f, l;

inclusive, for locking and releasing them with respect to the shaft [4. Specifically, this locking means comprises a plurality of locking members 2la-2 I j, inclusive, (Figs. 4, 5 and 6) individually interposed between the positioning cams [So-- inclusive, and the shaft M for individually releasably locking the positioning cams to the shaft in any desired relative angular positions. As shown most clearly in Fig. 4, each of the locking members, for example the locking member 2 la, comprises a resilient deformable member disposed in one of the recesses, such as the recess 14a, and is preferably in the form of an annular expansible member such as a split sleeve, as shown, of an undeformed outer diameter equal to or slightly less than that of the shaft I4 and of a thickness somewhat greater than the shaft l4 so that the portions 2la1 and 21m adjacent the split project inwardly through the apertures Mb on the opposite sides of one of the bars 140. The member 2 la opposite the split has a longitudinal recess 2 lag, which is adapted to engage the other of the bars Mc joining the adjacent shaft sections so that the member 2la will fit smoothly within the cylindrical recess Ma. By cutting the recess 2| as' in the sleeve 2la, it is also made somewhat more flexible to facilitate its deformation.

The positioning apparatus also includes means for deforming the locking members 2Ia--2If, inclusive, individually to engage their respective positioning cams l5a-l 5f, inclusive, to lock them to the shaft. This deforming means constitutes an elongated axially adjustable member 22 shown as a U-shaped or channel-shaped element of stamped sheet metal. The member 22 is disposed within the hollow shaft M for rotation therewith and is provided with a plurality of upstanding wedging portions 22a-22f, inclusive, which are adapted to engage the inwardly projecting portions of the split locking sleeves 2la2 I ,f, inclusive, for actuating or deforming the same to release or lock their respective positioning cams l5a -l 5f, inclusive; that is,' the axially adjustable elongated member22 and its associated'upstanding portions 22a,22j, inclusive, constitute adjustable camming means engaging and spreading the several split-sleeve locking members 2 la2 If, inclusive.

As stated above, it is desirable in mechanical tuners to which the positioning apparatus of the invention is applied to be able to lock or release the several positioning cams from the front of the receiver cabinet. To this end, there is provided an operating knob 23 extending through the front wall 24 of the receiver cabinet and mounted on an axially adjustable shaft 23a having thereon a circumferentially grooved collar 23b engaging one arm of a bell crank lever 25 pivotally mounted at 25a in the frame 28. The other arm of the bell crank 25 is connected to a circumferentially grooved collar 26 secured to an extension 225/ of the member 22. Also mounteclon the shaft 23a of the knob is an elongated pinion 23c engaging a crown gear 21 mounted on the shaft I4.

It isbelieved that-the operation of the shaftpositioning apparatus of the invention will be clear from the foregoing description. In brief, assume that it is desired to change the setting of one of the shaft-positioning members, such as the cam [5a, to effect a tuning of the receiver upon the depression of the cam operator l8a to a different broadcasting station. The knob 23 is pushed in, actuating the bell crank lever 25 to adjust the member 22 to the right, as illustrated in Fig. 2, thereby withdrawing the camming portions 22a--22f, inclusive, of the member 22 from the split sleeves 2Ia2lf, inclusive, so that the sleeves contract the portions thereof adjacent their respective splits projecting inwardly through the apertures Mb in the shaft 14. Positioning cams [Ea-45f, inclusive, are then free to be rotated under the control of their respective buttons l8al8f, inclusive.

The adjusting knob 23 is then turned to rotate the shaft l4 through the

gearing

23c, 27 to adjust the tuning condensers I0 and H to tune the receiver to the desired broadcasting station. With the knob 23 retained in this position, the camoperating button la is depressed and its roller Zlla engages the positioning cam l5a, rotating it on the shaft 14 until the roller 20a rests in the depression in the cam, that is at the point of the cam of minimum radius. During this resetting of the cam l5a, the other cams l5b-l5f are undisturbed due to the interposed spacing washers Ila-4 1e, inclusive, which are secured to the shaft it against rotation. The adjusting knob 23 is then pulled outwardly, without rotating it, thereby actuating the bell crank lever 25 in a clockwise direction and forcing the member 22 to the left as illustrated in Fig. 2 so that its several camming portions 22a-22f, inclusive, re-engage the split sleeves 2|a2lf, inclusive, expanding or deforming them to re-engage their respective positioning cams I5a-l5,f, inclusive. Obviously, a resetting of any of the other positioning cams l5b-l 5f, inclusive, is effected by a similar operation.

Thus, it is seen that there is provided a single means, that is the adjusting knob 23, operable from the front of the receiver cabinet 24, for axially adjusting the locking means comprising the member 22 and the split sleeves Zl-a -Z-lf', inclusive, to lock or release the positioning earn-s lira-l), inclusive, with respect to the shaft l4 and also for rotating the shaft I4 to tune the receiver to any desired broadcasting station as a step in resetting the positioning cams lbw-Hi,

inclusive.

In Figs, '7 and 8 is rep-resented a modified form of the locking means of the invention. In this arrangement, a hollow rotatable shaft 3-4; is provided with a series of segmentalcircumferential apertures him-E ie, inclusive, the adjacent sections of the shaft being joined by segmental portions such as the portions 3 37. Within the segmental apertures are disposed a plurality of annular spring-locking members tfiatte, inclusive, which, as shown in Fig. 8, are ribbed or corrugated so that they substantially fill the segmental apertures 3 iaf.de, inclusive, but are interrupted by the segmental shaft portions 3d In this case, the elongated axially adjustable member is in the form of a solid shaft 31 having a series of enlarged portions "la-31c, inclusive, which when positioned to engage the spring locking members 35a--85e, inclusive, are effective to deform or expand them to engage or grip their respective positioning cams Elia-45c, inclusive. In all other respects, the operation of the positioning apparatus including the locking means of Figs. 7 and 8 is similar to that describing the operation of the positioning apparatus of Figs. 1-6, inclusive, and need not be repeated.

While there have been described what are at present considered to be the preferred embodiments of the invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit or scope of the invention.

What is claimed as new is:

l. Positioning apparatus comprising, a rotatable shaft having a recess therein, a shaft-positioning member rotatably mounted on said shaft and at least partially covering said recess, means for releaeably locking said shaft to said member in any desired relative angular position including a resilient deformable locking member di posed in said recess, and means for deforming said locking member to engage said positioning member.

2. Positioning apparatus comprising, a hollow rotatable shaft having an aperture therein, a shaft-positioning member rotatably mounted on said shaft and at least partially covering said aperture, and means for releasably locking said shaft to said member in any desired relative angular position including a resilient deformable locking member disposed in said aperture, and means for deforming said locking member to engage said positioning member.

3. Positioning apparatus comprising, a hollow rotatable shaft having an aperture therein, a shaft-positioning member rotatably mounted on said shaft and at least partially covering said aperture, and means for releasably locking said shaft to said member in any desired relative angular position including a resilient deformable locking member disposed in said aperture, and axially adjustable means disposed within said shaft for deforming said locking member to engage said positioning member.

4. Positioning apparatus comprising, a hollow rotatable shaft having an aperture therein, a shaft-positioning member rotatably mounted on i rotatable shaft having a circumfere 6.. said'shaft and at least partially covering aperture, and means for releasably locking s shaft to said member any desired relative angular position including an. annuliai' expansrb locking member including a portion project i inwardly through. said aperture, and means for expanding said locking member to engage said positioning member.

5. Positioning apparatus compris' and an aperture therein, a shaft-positic ber rotatably mounted on said shaft and at partially covering said recess, s fer i1ele'asabl y locking said shaft to said in Y desired relative angular position inclu silient deformable locking member (1 posed in said recess and having a portion projecting: in.- wardily through said aperture, and axially ac justable means disposed within said shaft for engaging said projecting portion of said locking member to deform the same, thereby to engage said positioning member.

6. Positioning apparatus comprising, a hollow rotatable shaft having a circumferential recess and an aperture therein, a shaft-positioning member rotatably mounted on said shaft and at least partially covering said recess, and means for releasably locking said shaft to said member in any desired relative angular position including a resilient split sleeve disposed in said recess and having a portion projecting inwardly through said aperture, and axially adjustable camrningmeans disposed within said shaft to engage the split in said sleeve to expand the same, thereby to engage said positioning member.

'7. Positioning apparatus comprising, a hollow rotatable shaft having a segmental circumferential aperture therein, a shaft-positionin member rotatably mounted on said shaft and at least partially covering said aperture, and means for releasably locking said shaft to said member in any desired relative angular position including 'a resilient annular spring locking member disposed in said aperture, and an axially movable camming member disposed within said shaft to expand said spring locking member, thereby to engage said positioning member.

8. Positioning apparatus comprising, a rotatable shaft, a plurality of axially spaced shaftpositioning members rotatably mounted on said shaft, a plurality of members for individually releasably locking said positioning members to said shaft in any desired relative angular positions, and an elongated axially adjustable member engaging said locking members for actuating and releasing the same to release or look said positioning members with respect to said shaft.

9. Positioning apparatus comprising, a rotatable shaft, a plurality of axially spaced shaft-posttioning members rotatably mounted on said shaft, a plurality of locking members individually interposed between said positioning members and said shaft for releasably locking said positioning members to said shaft, and an elongated axially adjustable member engaging said locking members for actuating and releasing the same to release or lock said positioning members with respect to said shaft.

10. Positioning apparatus comprising, a rotatable shaft having a plurality of axially spaced recesses therein, a plurailty of axially spaced shaft-positioning member rotatably mounted on said shaft and at least partially individually covering said recesses, a plurality of resilient deformable locking members individually disposed 7 in said recesses, and an elongated axially adjustable member engaging said locking members for actuating and releasing the same to release or look said positioning members with respect to said shaft.

11. Positioning apparatus comprising, a hollow rotatable shaft having a plurality of axially spaced apertures therein, a plurality of axially spaced shaft-positionin members rotatably mounted on said shaft and at least partially individually covering said apertures, a plurality of resilient deformable locking members individually disposed in said apertures, and an elongated axially adjustable member disposed within said shaft and engaging said locking members for actuating and releasing the same to release or look said positioning members with respect to said shaft.

RICHARD C. MARI-IOLZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS