US3194086A - Positioning mechanism - Google Patents

Description

. ly 1965 J. E. LASCHENSKI 3,194,086

POSQETIONING MECHANISM Filed July 13, 1961 4z q% m V /5 F151. F 33 United States Patent 3,194,6d6 IGSHTIGNING MECHANlSM Joseph E. Lasehenski, Philadelphia, Pa, assignor, by

mesne assignments, to Philco Corporation, Philadelphia, 79s., a corporation of Delaware Filed July 13, 1961, Ser. No. 123,766 3 tllaims. (El. 74-668) This invention relates to positioning mechanisms, and more particularly to mechanisms for positioning rotatable shafts. 1

While of broader applicability, the invention has particular utility in shaft positioning apparatus of the type disclosed and claimed in the copending application of Albert LaBov, Serial No.728,471, filed April 14, 1958, now US. Patent No. 3,065,398, issued November 20, 1962, and assigned to the assignee of the present invention.

The present invention has as its primary obiective the provision of improved adjustable indexing means for use inapparatus of the aforementioned type and adapted to operate an electronic tuning device through predetermined sequential angular increments.

Another object of the invention is the provision of adjustable indexing means which is characterized by its simplicity of construction and effectiveness of operation.

A specific object of the invention is the provision of an indexing wheel which includes indexing elements that are readily accessible and selectively adjustable by the user.

in a preferred embodiment of the invention there is provided a motorized self cycling drive mechanism for positioning a rotatable shaft to be moved sequentially through predetermined angular increments by a motor, each angular increment corresponding to a different television channel as provided by rotatable channel selector means coupled with the rotatable shaft. Indexing means is driven with the shaft and is so constructed and arranged as operatively to engage a switch controlling lever adapted to deenergize the motor when the shaft is rotated to the next preselected index position. In particular accordance with the invention, the indexing means comprises a novel programming knob or wheel including a body portion provided with a plurality of axially extending keyways within which key elements are slidable, and flexible and resilient band means encircling said body portion and frictionally engaging the slidable key elements to maintain positions of the latter. The key elements are disposed parallel to and radially spaced from the axis of the mounting shaft to provide detent means for controlling the switch at the selected stations. 'Each key element includes detent means within which the band encircling the knob body is received to maintain positioning of a key element in its preselected position.

It is a feature of the invention that the shaft to be positioned extends through suitable mounting structure, such for example as a cabinet, one end of the shaft being adapted to support amanual actuating knob and the other end adapted to support the indexing means. By this novel arrangement, both the knob and the indexing means are visible and accessible to a user.

From what follows it will be appreciated that the invention also features controlling mechanism for a switch characterized by its ease of adjustment, simplicity of construction, and effectiveness of operation.

The manner in which the foregoing objects and advantages may best be achieved will be understoodfrom a consideration of the following description taken in light of the accompanying drawing in which:

FIGURE 1 is a side elevational showin of apparatus embodying the invention, with parts broken away, and includes an electrical wiring diagram;

dfi lfi fi Patented July 13, 1965 FIGURE 2 is a front view, in elevation, of the apparatus seen in FIGURE 1, with parts removed; and

FIGURES 3 and 4 are showings similar to FIGURE 1, with parts removed and broken away, and illustrating novel features of the indexing knob.

Now making more particular reference to the drawing, and first to FIGURE 1, a shaft positioning mechanism it) is coupled with a rotatable shaft 11 to be driven through predetermined angular increments, said shaft including an extension 11a adapted to drive, for example, a television channel selector or tuner 12. Shaft 11 also includes an extension 11b protruding with clearance through a wall 47 of cabinet structure 45. A knob 13 is ZIlIlXtDd to extension 11b, whereby manual rotation of shaft 11 and tuner 12 is afforded. The positioning mechanism further comprises reduction gear means (not shown) which may be of known type disposed within a housing 14 and affording a drive coupling between the shaft 11' ing 14 and to bracket means 18 affixed to the motor.

Rotor 21 and shaft 22 are axially movable as a unit, in response to energization and deenergization of the motor. Compression spring 17 projects between rotor 21 and housing 14- resiliently to urge the rotor to the extended or deenergized position as shown, Whereas the rotor and its shaft 22 is urged to the left, as seen in FIGURE 3, upon energization of the motor. The end of shaft 22 journalled within housing 14 includes a pinion (not shown) releasably engageable with the aforementioned drive gear means, and in response to the aforementioned axial movements of rotor 21.

With reference also to FIGURES L2, 3, and 4, novel indexing means 23 for shaft 11 and tuner 12 comprises a knob 24 having a cup-shaped portion 25 and acylindrical or barrel-like portion 26 extending therefrom and provided with keyways 27 within which the indexing keys or key elements 31 are slidable. As will be hereinafter more fully explained, preselected keys 31 are moved outwardly of their keyways 2'7 predetermined distances to the position shown in FIGURE 1, to provide the desired predetermined angular increments corresponding to television channels of the illustrated tuner 12. p p

In order better to illustrate the cooperative action of the indexing means 23 with switch means 33, a key 31 has been removed from the uppermost k'eyway 27 in FIGURE 2. However, it will be understood that a key 31 will be retained within a keyway at all times, either.

in the fully extended positions shown in FIGURE 1 or in the fully inserted position shown in FIGURE 3.

With more specific reference to the indexing knob 24, and as already briefly described, each of the keys 31 comprises a substantially L-shaped elemnet having a generally rectangular main body portion 38. The main body portion 38 comprises the bearing surface of a key 31, and p a the angular or stepped portion 39 comprises stop means which, in cooperation with stop means provided in keyway 27, prevents inadvertent removal of a key 31 from its keyway. Each key 31 is provided with spaced grooves id, itle which extend transverse its body portion 38 and are aligned along the peripheral surface of the generally cylindrical barrel-like portion 26 of the knob. A coil spring 43 is tensioned about portion 26 and nests within the aligned grooves dtlb of the latter and grooves dtl, of keys 31, such alignment depending upon the positions of the keys. It is this frictional engagement by the resilient spring 43 that holds the keys in their selected positions. By this arrangement, keys 31 are slidable within keyways 27 between. the positions provided by the grooves l-(l, ltla, in cooperation with spring 43.

The tab-like ends 44 of keys 31 are disposed within the cup-like portion 25 of knob 24 and are accessible through a countersunk opening 4-5 provided, for example, in a wall 48 of cabinet structure 45 within which the positioning mechanism is disposed. Key ends 44 are formed as tabs to enable an operator to grasp a key 31 and slide the same either to a full inner or left-hand position (FIGURE 3) or to a full outer or right-hand position (FIGURE 1). It will therefore be appreciated that the invention is characterized by its compactness and facility of operation, inasmuch as shaft 11 is double ended, having knob 13 at one end, adjustable indexing means at the other end, and mechanism rotatable therewith disposed intermediate the shaft ends and Within cabinet structure When a key 31 is in its outer position (see also FIG- URE 2), its keyway 27 is vacated for a major portion of its length. An open keyway 2? permits the switch controlling cam 41 to fall into the open keyway or groove 27, under the urging of resilient switch arm 35, and open switch 33. In the inner position of a key 31 (FIGURE 3), cam 41 will ride along the substantially smooth surface presented by knob portion 26 and keys 31, thereby maintaining closure of switch 33, and energization of motor 15, until the cam 41 enters the next successive keyway 27, which operation will hereinafter be more fully described.

The knob 24 conveniently may be made of molded plastic, as well as may keys 31. Each of keys 31 is removable from the knob by moving the key to its outer position (FIGURE 1), followed by forcing the tab portion 44- toward the center of the knob (FIGURE 4), against the resilience of spring 43, to move stop 39 clear of stop 50. At the same time the key is pulled from the keyway 27, thereby removing the same in the general direction of the arrow. Conversely, a key is insertable into a keyway by inserting the end provided with a taper 3&1 (FIGURE 4) and forcibly Wedging the taper against the spring 43. Continued forcing of the key disposes either of grooves dila or 4-0 for engagement by the spring, depending upon the desired operational position of the key.

It is a feature of the indexing means that all desired channels or indexed positions are accessible at the same time and can be programmed without rotating the tuner to a specific channel position for acceptance or rejection. Also the knob 24 serves as a rotatable member for manual channel selection, in which event the knob is grasped by its cup-like portion 25 that extends through countersunk cabinet opening 46.

With additional reference to the positioning mechansim, motor shaft 22 is provided with an electrically non-conductive, cone-like cam member 32 which is releasably engageable with the upper, resilient arm 34 of switch 33, in response to axial movement of the shaft 2 2. The other, or lower, arm 35 of switch 33 is also resilient, and each of arms 34 and 35 are provided with electrical contacts as and 37. Engagement of switch arm 34 by cam member 32 (FIGURES 1, 2 and 4) moves the arm to maintain the switch contacts 36 and 37 apart to ensure deenergization of motor 15. Conversely, disengagement of switch arm 34 by the cam member 32 permits resilient arm 34 to move contact 36 toward the closed switch position for engagement by contact 37 as the latter moves upwardly to maintain energization of motor 15. Cam portion 41 affixed to switch arm 35 is releasably engagcable with indexing keyways 27 formed in indexing knob 24 to control switch arm 35 either to deenergize or maintain energization of motor 15.

In operation of the apparatus, and with reference to the electrical circuitry shown in FIGURE 1, initiation of the positioning function is achieved by closing of a momentary switch 42 connected in series electrical circuit with line L and motor 15, which closing of the switch energizes the motor. Immediately upon energization of the motor, rotor 21 and shaft 22, along with the cam element 32-, move to the leftmost position as seen in FIGURE 3. This Cir movement of cam element 32 releases resilient switch arm 34. Substantially simultaneously with the release of switch arm 34, the motor rotationally drives the shaft 11 and the indexing wheel 24, moving the keyway 27 from the path of the switch arm cam portion 41. The cam portion 41 then is engaged by the cylindrical knob portion 26 and the fully inserted keys 31, in which instances arm 35 is so positioned as respects arm 34 to effect closure of the holding switch contacts 36 and 37, which contacts are connected in parallel electrical circuitry with momentary switch The mechanism will then move tuner 12 to its next indexed position, which is the next open keyway seen in FIGURE 1, whereupon cam portion 41 will engage the open keyway to open switch 33. This deenergizes the motor and permits the rotor to move cam element 32 to its switch engaging position.

Manual rotation of shaft 11 by either of knobs 13 and 2.4 is achieved independently of the motor drive means while the latter is deenergized, inasmuch as switch 33 is held open through the positive restraint of resilient actuating arm 34 by cam element 32 mounted on the motor shaft. The positioning mechanism may be caused to operate past undesired indexed shaft positions by holding the momentary switch 42 closed until the shaft has rotated past these positions. Release of the switch just prior to the desired shaft position will of course result in automatic selection of this position by the mechanism.

While no detent means has been illustrated for holding shaft 11 in its respective indexing positions it is to be understood that such means may be provided as an integral part of the driven tuner 12.

I claim:

1. Controlling mechanism for av switch, comprising: rotatable wheel means including a cylindrical portion having a plurality of generally parallel keyways in peripheral surface portions thereof and extending parallel to the axis of said wheel means, and an axially extending recessed portion disposed at one end of said cylindrical portion; and switch controlling key means disposed within each of said keyways and slidable therein between positions for engaging and disengaging such switch means, ends of said key means extending into said recessed portion and comprising tab portions accessible within said recessed portion and providing for adjustable positioning of said key means, each said key means including a step portion and each said keyway including a mating step portion, said step portions being disposed and adapted for intereng-agement when a key means is in one of its pair of positions whereby removal thereof is normally prevented, each said key means further being removable and insertable with respect to a keyway by pivoting of the tab portion thereof toward the axis of said wheel means, whereby to disengage said step portions, then by sliding said key means relative to said keyway.

2. Combined indexing Wheel and knob means for positioning a rotatable shaft, comprising: a main barrel portion having axially extending keyways defining predetermined indexed positions of a shaft to be positioned; a generally cup shaped portion aligned axially with said main barrel portion, having its opening presented away from the latter and having openings therein aligned with said keyways; an indexing key element disposed within each said keyway and slidable therein through its opening into said generally cup shaped portion between a position in which a portion of the keyway is opened at least partially and a position substantially closing said keyway; and a resilient band reacting against said barrel portion and frictionally engaging said key elements to maintain preselected positions of the latter within said keyways, said cup shaped portion being configured and disposed to provide for manual rotation of said shaft.

3. Indexing wheel means according to claim 2, and further characterized in that each said key element and each said keyway includes abutment means disposed and adapted for interengagement whereby to prevent removal 5 of a key element upon adjustment thereof between its recited positions, ends of said key elements being tiltable toward the axis of the Wheel means to overcome the recited interengagement to provide for removal and insertion of the key elements.

References Cited by the Examiner UNITED STATESPATENTS 1,780,328 11/30 Ames 74568 Raber 200-38.1 Barrett 74-5 68 X Somes 74568 Neweil 200-3 8 Papitto 318-467 Devend-orf 318-467 Jackson 1787.9

Archer 1787.9

1,882,495 10/32 Hipp ZOO-38.1 10 PROUGHTON G. DURHAM, Primary Examiner.

Claims (1)

1. CONTROLLING MECHANISM FOR A SWITCH, COMPRISING: ROTATABLE WHEEL MEANS INCLUDING A CYLINDRICAL PORTION HAVING A PLURALITY OF GENERALLY PARALLEL KEYWAYS IN PERIPHERAL SURFACE PORTIONS THEREOF AND EXTENDING PARALLEL TO THE AXIS OF SAID WHEEL MEANS, AND AN AXIALLY EXTENDING RECESSED PORTION DISPOSED AT ONE END OF SAID CYLINDRICAL PORTION; AND SWITCH CONTROLLING KEY MEANS DISPOSED WITHIN EACH OF SAID KEYWAYS AND SLIDABLE THEREIN BETWEEN POSITIONS FOR ENGAGING AND DISENGAGING SUCH SWITCH MEANS, ENDS OF SAID KEY MEANS EXTENDING INTO SAID RECESSED PORTION AND COMPRISING TAB PORTIONS ACCESSIBLE WITHIN SAID RECESSED PORTION AND PROVIDING FOR ADJUSTABLE POSITIONING OF SAID KEY MEANS, EACH SAID KEY MEANS INCLUDING A STEP PORTION AND EACH SAID KEYWAY INCLUDING A MATING STEP PORTION, SAID STEP PORTIONS BEING DISPOSED AND ADAPTED FOR INTERENGAGEMENT WHEN A KEY MEANS IS IN ONE OF ITS PAIR OF POSITIONS WHEREBY REMOVAL THEREOF IS NORMALLY PREVENTED, EACH SAID KEY MEANS FURTHER BEING REMOVABLE AND INSERTABLE WITH RESPECT TO A KEYWAY BY PIVOTING OF THE TAB PORTION THEREOF TOWARD THE AXIS OF SAID WHEEL MEANS, WHEREBY TO DISENGAGE SAID STEP PORTIONS, THEN BY SLIDING KEY MEANS RELATIVE TO SAID KEYWAY.

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