US2548120A - Manual drive system for radio receivers - Google Patents

Description

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MANUAL DRIVE SYSTEM FR RADIO RECEIVERS Filed Oct. 22, 1948 3 Sheets-Shea?l l puil w, lll M. J. MFE@ ETAL 54%912@ MANUAL DRIVE SYSTEM FOR RADIQ RECEXVERS Filed oci., 22, 194e 3 Sheets-Sheet 2 pr U, 95 m. .A PAA-ER HAL 25439112@ MANUAL DRIVE SYSTEM FOR RADIO RECEIVERS 3 Sheets-Sheet 3 Filed Oct. 22, 1948 fornefy.

Patented Apr. 10, 1951 MANUAL DRIVE SYSTEM FOR RADIO RECEIV ERS Marion J. Pifer, Williamsville, and Alvin D. Meyer, Kenmore, N. Y., assignors, by mesne assignments, to New York, N. setts Sylvania Electric Products Inc., Y., a corporation of Massachu- Application October 22, 1948, Serial No. 55,928

2 Claims.

This invention relates to mechanism Which is particularly useful in radio receivers equipped with push button tuning for selecting predetermined stations, and with a manual control for selecting other stations.

In such apparatus, it is desired to have the push buttons operate with a minimum of pressure, and to have the manual control arranged with a considerable step down of motion from the manual control to the tuner. 'I'hese requirements made it necessary in the past to provide some form of clutch for connecting the manual control to the tuner when the manual control was desired to be used, and for disconnecting it when push buttons Were to be used, because the force required to opcrate the push buttons with the manual drive connected Was excessive.

In the past, this has required the addition of another control to the receiver, which the operator must remember to use.

It is an object of this invention to do away with this additional control, and to provide mechanism by which the manual control is automatically connected to the tuner without any other operation,

when the manual control is operated, and is automatically disconnected when any push button is operated.

It is a further object of this invention to provide mechanism of the class described which is positive and reliable in operation, involves only screw machine and punch press parts not requiring high precision, and requires no attention on the part of the operator of the receiver.

Still other objects, and advantages of our invention will be apparent from the specification.

W'hile the mechanism is of particular utility in connection with radio receivers, it will be understood that it has other applications, and may be advantageously employed in other apparatus wherein both push-button and manual control is desired, and wherein operation of either automatically disconnects the other, Without a separate operation.

The features of novelty which we believe to be characteristic of our invention are set forth with particularity in the appended claims. Our invention itself, however, both as to its fundamental principles and as to its particular embodiments, will best be understood by reference to the speci- Iication and accompanying drawing, in which Fig. 1 is a section through a tuner embodying our invention,

Fig. 2 is a similar fragmentary view on an enlarged scale of part of the mechanism shown in Fig. 1,

.bar I3 mounted on shaft I8 Fig. 3 is a section on line 3 3 of Fig. 2,

Fig. 4 is a section on line 4 4 of Fig. 2,

Fig. 5 is a section on line 5 5 of Fig. 4,

Fig. 6 is a section on line 6 6 of Fig. 5,

Figs. 7 and 8 are views similar to Fig. 6, but showing the mechanism in different portions of its operational cycle,

Fig. 9 is a View similar to Fig. 2, but showing the mechanism at a different point in its cycle of operation,

Fig. 10, is a view similar to Fig. 1 but with part of the push-button tuning mechanism removed for clarity, y

Fig. 11 is a detail view of a portion of the mechanism,

Fig. 12 is a detail View of a modified form, and

Figs. 13 and 14 are detail front elevation and top plan views of portions of the mechanism of the same modified form.

Referring now more particularly to Fig. 1, we provide a plurality of push buttons which may be preset or calibrated to adjust the tuner to select a predetermined station. Because the particular construction of the push buttons and the mechanism thereof is not, per se, a part of this invention, but is the subject of a copending application by us and Harold J. McGarvey, ser. No. 20,348, now Patent No. 2,530,663 assigned to the assignee of this application, only so much of the push button mechanism is shown and described as is necessary to an understanding of the present invention.

In the embodiment of the invention herein disclosed, which is for certain purposes the preferred embodiment, We employ push buttons such as Ill of the so-called piano key type, but other types may be equally well employed. In this embodiment, these keys I0 are pivoted side by side on shaft Illa mounted on the frame of the machine, and when depressed to tune a station, move from the full line position to the dotted line position of Fig. 1.

Each has an extensionv II carrying an adjustable rocker arm or tappet I2 which engages tilt which may be a continuation of the tuning condenser shaft, orgeared thereto. The tappet I'2 is secured in adusted position for a particular station by locking means which is not a part of this invention, but is claimed in the application above referred to.

Each key carries an upwardly extending pawl I 4 having a notch I5 in its upper edge to be engaged by latch I6 common to all the push buttons,

mounted on latch shaft Il and free to rotate through a; small angle, and spring or gravityI mitting the newly depressed key to change #the setting of the tuner to bring in the station desired, after which the latch engages .fthe newly depressed key to hold the -tuner in its'new position.

Manual adjustment of the tuner to a station not set up on the keys may be obtained by the rotation of manual control knob v2-5 ,mounted on manual shaft 2'6 in bearings 21 secured to fr ont panel 28 and connected to flexible shaft29 terminating in pinion 30 arranged to be engaged with or disengaged from crown gear 3l secured to tuner shaft '|g8. lIt will be clear, however, that manual control 25 cannot .be used to tune as long as any push button is .in depressed position. Therefore we provide mechanism whereby rotation of the manual control ,25 releases latch 41.6, permitting the formerly depressed .key to return to its initial positionand free the tuner Yshaft I8for rotation under control of the manual drive knob 25.

kAn important part of this mechanism is vthe latch actuating lever Figs. 2, 3 and 9) consisting of a pair of spaced arm portions 36 and .31 joined together by connecting'portion 38. 'The latch actuating lever 35 is pivoted on shaft ,lila adjacent -one end 'thereof and adjacent the manual control 25, as best seen in Fig. 3. The upper end of the latch actuating lever .35 has a latch release cam surface 39, which, =uponslight clockwise rotation of the latch actuating lever yfrom the position of Fig. 2, engages latch i6 and lifts it, releasing any Ykey Il! -Which may have been depressed. If the latch actuating lever is'rotated clockwise to the full extent of its movement, the latch I6 rides into latching notch 40 as -shown in Fig. 9, holding the latch actuating lever in the position of Fig. 9 against the pullof latch actuating lever return spring 4l secured to the latch actuating lever` and to the frame, and the 4latch actuating lever will remain latched in this position until one of the keys i9 is depressed'to select its station. This action lifts the latch I6, permitting the latch actuating lever to return to the position of Fig. `2.

vIn one form of our invention, the `'lower end .of arm 31 of the latch actuating lever 35 carries three inwardly projecting studs A45, .46, and 41, each of these being grooved as best seen in Figs. .6 and 7. Mounted on stud 41 is provided the rectangular flipper plate provided with opening Y5l to receive stud 41 and permit the flipper'plate 50 to move to the right and left, within lnmts, as seen in Figs. 6 and '1. Notches 52 and 53 are provided on the left hand edge of flipper plate 50 to receive studs 45 and 4B. Flipper plate 5U also carries an inwardly projecting stud 55.

Mounted on and driven by the manual shaft 26 there is provided a cupped cam 55, having axiallyprojecting cam teeth 51. When the mechanlsm 1s ,in the position of Fig. 2, the flipper plate 50 is at .the right hand extremity of its travel, in theposition shown in Fig. 6, and stud 55 is in PUSH/.10.1.1 '.09 be engaged by the axially projecting cam teeth 51 of cupped cam 56. It will be remembred that the mechanism will be in the posi, 4

tion of Fig. 2 whenever any station selector push button l0 is depressed to tune a station.

If a station selector key is depressed and the operator wishes to tune the set manually to select a station for which the push buttons are not set, he will simply grasp manual drive knob and start rotating it. The direction of rotation makes Ano difference, as the following action occurs for rotation .of the manual knob in either direction.

One of the cam teeth 51 engages stud 55 and moves flipper plate 5U to the left from the position of Fig. 6 to that-of Fig. 'I at which time the clearance in holes 25|, 52, and 53 from studs 45,

46, and 41 Vis taken up, and further rotation of the manual knob applies force to the lower end of arm 31 of the latch actuating lever 35, rotatin g it-clockwise tto the position of Fig. 9, lifting latch Ii and releasing any key I which may have been depressed, freeing the tuner shaft I8 for rotation, and latching the latch actuating lever in the position of Fig. 9.

The flipper plate 50 is provided with a notch 60, vand a leaf spring 6I is secured to the outer side ofthe flipper plate, and its free end passes through the notch 60 and is engaged between the arms of bifurcated bracket 62 mounted on the `frame. This spring is so chosen and mounted that When the flipper plate is at the right hand end of its travel, as in Fig. 6, it urges the right hand end of the flipper plate upwardly, whereas Awhen the flipper plate is at the left hand end of its travel, it urges the right hand end of the flipper plate downwardly, as seen in Fig. 8.

The action of spring (5| on flipper plate 50 -is as follows:

'The spring 6| exerts no pressure on flipper plate 55 when the plate 50 is at an intermediate point between the extremities of its movement to right or left, as seen in Figure 8. lAt either extremity of movement, however, the action of the bracket G2 exerts a pressure on the free end of spring 6I rtending to close the spring on itself when the flipper plate is at the left hand extremity of its movement and to open the spring when the Vflipper plate is at the right hand extremity of `its movement. This force is in turn transmitted to the mounting end of the spring 46l in a downward direction when the flipper plate is at the left hand extremity of its motion and in an vupper direction when the flipper plate is at the right hand extremity of its motion. Expressed in terms of mechanics, when the plate 58' moves to the left looking at Figure 8, the pressure on the left hand side of spring 6| introduces a clockwise rotational couple on flipper plate 50 causing it to pivot about its left hand edge. When flipper plate moves to the right, spring 6l introduces a counter-clockwise rotational couple causing the flipper plate to rotate in a counterclockwise direction on its pivot axis.

Consequently, as the manual knob is rotated further, after the mechanism has reached the position of Fig- 9, tooth 51 of cupped cam 55 passes out of engagement with stud 55, and the spring 6| rotates the flipper plate slightly clockwise to the position of Fig. 8, in which stud 55 is out of the path of the teeth 51 of cupped cam 56, and the manual knob may now be rotated freely to select any station manually. It will be noted that as long as a tooth 51 is pressing against stud 55, and thereby pressing flipper plate against studs 45, 45, and 41, the rotation of flipper plate cannot occur. This occurs only after latch actuating lever 35 has been latched in its clockwise position and further rotation of the manual knob has released contact between teeth 51 and Astud 55.

To facilitate adjustment of spring 6|, bracket 62 is preferably adjustably mounted on the frame of the instrument so that its position can be changed for best results, and is secured in ad justed position by a locking screw, 53 shown in Figures 3 and 4.

If a station selector key is now depressed, this first releases latch l5, permitting latch actuating lever 35 to rotate counter-clockwise, returning to initial position. The flipper plate 5U will then be rotated counter-clockwise from the position of Fig. 8, and will tend to return to the position of Fig. 6. If cam 56 happens to be in position such that stud 55 does not clear teeth 51 this does not matter, because as soon as the manual shaft is rotated slightly, the teeth will clear the stud, and the flipper plate 5!) will return to the position of Fig. 6, and further rotation of the manual shaft will engage the stud with a cam tooth and produce the action already described.

The rearward motion of the flipper plate 50 under the action of the cupped cam 56 allows engagement of the pinion 3l) on flexible shaft 29 with crown gear 3| on the tuning shaft I8 in a manner` which will now be described.

The pinion end of the exible shaft 29 is carried in ears 'Ha and 1lb on bracket 10 (Fig. 10) secured to a leaf spring 1i, which is in turn secured to plate 12 secured to the frame of the machine, and the bracket lll carries a third ear 1 Ic engaged by stud 1li on arm 36 of latch actuating lever 35 (Fig. The spring mounting of the bracket 10 permits it to rotate slightly as shown by the full and dotted lines of Fig. 11 by llexing of the spring 1 i.

When no pressure is applied to bracket 10, and it is free to assume the position normal to spring 1I, it takes the dotted line position of Fig. 11, in which pinion 3B is engaged with crown gear 3l. This is the position it assumes upon rotation of the manual control knob 25, after latch actuating lever 35 has been latched in the position of Fig. 9. In this position, the manual knob may be rotated to adjust the tuner to any desired station manually.

When any key IU is depressed to select a station, the latch actuating lever 35 is released, as already described, androtates slightly counterclockwise under the tension of spring 4l. This presses stud ifi against ear 13 of bracket 10, rotating bracket 10 slightly clockwise to the full line position of Fig. 1l, disengaging pinion 3D from crown gear 3l and leaving the tuner free to operate without driving the manual knob 25 through pinion 3B.

It should be noted at this point that this construction provides another benerlt. Should the tuner be of the type which has only 180 rotation, when the tuner comes against the limiting stop, further attempts to rotate manual knob 25 simply flex spring "il, and pinion 3B slips on crown gear .t I, signalling the operator that he has reached the end of the tuner travel. As soon as he begins to turn the knob 25 in the opposite direction, the gears drop back into engagement, and the tuning can be continued in the reverse direction. The same action occurs when the tuner reaches the other end of its travel.

Referring now to Figs. 12, 13, and 14, we have shown a slightly modified form of our invention. In this form, studs d5, i6 and 41 are eliminated, and iiipper plate 50 is pivoted on arm 31 of latch actuating lever 35, in ears 8B and 8| formed thereon, and stud 55 is slightly grooved or undercut as at 32 to prevent the teeth of Acupped cam 56 from slipping off the stud, before the teeth 51 have disengaged themselves from stud 55.

Instead of the stud 14 engaging ear llc to disengage pinion 3i] from crown gear 3l, bracket T0 is provided kwith an extension carrying an ear 86, engaged by a projection 81 formed on arm 36 of latch actuating lever 35.v The outer end of arm 81` is turned to provide an anchor point for spring 89, the opposite end of which is connected to the end of arm 85.

The operation is the same, however. As latch actuating lever 35 rotates clockwise, arm 81 is carried to the left in Fig. 12, and arm 85 on bracket 10 rotates counter-clockwise by the iiexing of spring 1|, carrying pinion into engagement with crown gear 3l. When any key l0 is depressed t0 select a station, latch actuating lever 35 is released and the pull of spring 4l returns the mechanism to the position of Fig. 2.

In the specification, we have explained the principles of our invention and the best mode in which we have contemplated applying those principles, so as to distinguish our invention from other inventions; and we have particularly pointed out and distinctly claimed the part, improvement or combination which we claim as our invention or discovery.

While we have shown and described certain preferred embodiments of our invention, it will be understood that modifications and changes may be made without departing from the spirit and scope thereof, as will be clear to those skilled in the art.

We claim:

1. In a radio receiver having a tuner, a plurality of pushbuttons and a manual drive for operating said tuner, a shaft for rotating said tuner having a gear, a second gear on said manual drive for engaging the iirst said gear, said second gear mounted for movement toward and away from the first said gear, and biased toward engagement with the rst said gear, a pivoted lever having a portion restraining movement of said second gear into engagement with the first said gear, a ipper plate mounted on said lever for translational and limited swinging movement, a cupped cam mounted on said manual drive and engaging said iiipper plate to produce translational movement thereof, and partial rotation of said pivoted lever, spring means secured to said flipper plate to effect swinging movement thereof out of engagement with said cam at the extremity of movement thereof effected by said cupped cam, and latching means for releasably holding said pivoted lever in the position to which it is moved, by said cam, whereby said second gear is biased into engagement with the rst said gear.

2. In a radio receiver having a tuner, a plurality of pushbuttons and a manual drive for operating said tuner, a shaft for rotating said tuner having a gear, Ia second gear on said manual drive for engaging the first said gear, said second gear mounted for movement into and out of engagement with the first said gear and biased toward engagement, a pivoted lever having a portion restraining movement of said second gear into engagement with the rst said gear, a flipper plate mounted on said lever for limited translational and swinging movement,l a, cupped cam mounted on said manual drive and engaging said flipper plate to produce translational movement thereof and partial rotation of said pivoted lever,

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

Number UNITED STATES PATENTS Name Date Lester Dec. 18, r1888 Schwarz etal. Oct. 14, 1941 Schwarz et al Sept. 15, 1942 McGarvey Mar. 20, 1945

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