US2786907A - Control device - Google Patents

Description

March 26, 1957 J. HARRIS CONTROL DEVICE 2 Sheets-Sheet 1 Filed April 27. 1955 Mix]. I!

March 26, 1957 J. L. HARRIS CONTROL DEVICE 2 Sheets-Sheet 2 Filed April 27, 1955 CONTROL DEVICE John L. Harris, Whitefish Bay, Wis.

Application April 27, 1955, Serial No. 504,173

7 Claims. c1. zoo-3s This invention relates generally to timing devices in which a controlling impulse initiates a timing period which is then automatically terminated at the end of a predetermined, timed period.

Devices of this type are today used extensively in, for example, automatic dispensing apparatus, and may be manually controlled, coin operated, or may receive the controlling impulse from other automatically operated mechanisms.

The widespread use of such timing devices has, of course, resulted in a demand for a rugged, trouble-free interval timer which will perform the function required and yet have its components so arranged that the assembled timing device is of minimum size and can, therefore, be easily integrated into the quipment which it is to control.

A primary object of the present invention is to provide a timing device which has its components so arranged as to provide for maximum ruggedness and accuracy in a housing of minimum over-all dimensions.

A further object is to provide a timing device in which the flexible contact-carrying blades are so formed as to localize the bending stress therein as the contact-carrying blades are operated, the major portion of the blade length thereby retaining the rigidity required for accurate functioning of the device.

A further object is to provide a timing device in which the operating cam moves through the major plane of the contact-carrying blades as the device operates, this arrangement permitting the optimum use of the restricted housing space available.

A further object is to provide a timing device in which the contact-carrying blades straddle the operating cam'the assembly thereby attaining a more balanced and rugged operating characteristic without a requirement for holding close dimensional tolerances in forming its component parts.

A further object of the invention is to provide a timing device which, because of the arrangements of its components, is easily adaptable to either manual initiation of the operating impulse, coin operation, or actuation by other automatic mechanism.

Other objects of the invention will appear from the following description and the appended claims.

For a full disclosure of the invention, reference is made to the following detailed description and to the accompanying drawings in which:

Figure l is a top view of the timing device, showing a portion of its mounting panel.

Figure 2 is an end view of the timing device with the appropriate side of the housing removed.

Figure 3 is a front view of the timing device with the face portion of the housing removed.

Figure 4 is an enlarged fragmentary View, partially in section, of certain of the timing device components shown in Figure 3.

Figure 5 is a front view of a modification of the timing States Patent 0 device previously illustrated, certain portions of the housing being broken away to better show the components.

Figure 6 is an end view of the device shown in Figure 5, with a portion of the housing broken away.

Figure 7 is a front view of a further modification of the timing device, certain portions of the housing being broken away to better show the components.

Figure 8 is an end view of the device shown in Figure 7, with a portion of the housing broken away.

Referring to Figures 1, 2, 3, and 4, a timer housing 1 supports, by means of mounting studs 2, a synchronous motor, having a field coil and core assembly 3 and a gear train casing 4. The output shaft of the gear train carries a pinion gear 6 which extends into the housing 1.

A central pin 7 extends across the housing 1 and is rigidly supported by the front and rear walls of the housing. A sleeve 8 is rotatably carried by the pin 7 and rigidly mounts a gear 9 and a cam 11 having a dropoff portion 10. A sleeve 12, having a flanged head 13, is also carried by the shaft 7. A compression spring 14 extends between the housing 1 and the flange 13, serving to urge the sleeve 8 to its furthermost left-hand position as viewed in Figure 2. The slight gap between the end of sleeve 12 and the rear face of housing 1 permits slight variations in the positions of the just described components to thereby accommodate dimensional variations occurring in the manufacture of, for example, housing 1.

From the foregoing it will be understood that the pinion 6, meshing with gear 9, drives the cam 11 in a clockwise direction, as viewed in Figure 3.

As may best be seen in Figure 3, mounted on an insulating panel 16, carried by housing 1, are two rigid, right-angle brackets 17 and 18. The brackets 17 and 18 have rigidly mounted thereon, by riveting or any suitable means, contact-carrying blades 19 and 21, respectively. Blades 19 and 21 carry, at their free ends, electrical contacts 22 and 23, respectively, and the blade 19 has a channeled, shank portion having upturned margins 24. Blade 21 has a similar channeled portion with downturned margins 26. The terminal portions 27 and 28 of the blades 19 and 20, respectively, are flat and do not have the channeled cross-section of the shank portions of the blades.

As may best be seen in Figure 4, in both blades 19 and 21 the central, web-portion is slotted, to permit the cam 11 to extend through the major plane of the blades, the shank portion of the blades thereby straddling the cam 11. It will be noted that the central slot in blade. 19 is longer than that in blade 21, and that while cam 11 extends through the blade 19, only blade 21 actually rides the periphery of the cam 11.

Adjacent the upper corner of the housing 1, a pin 29 extends thereacross and rotatably carries a sleeve 31 having a central, splined portion on which is mounted a latch member 32. A torsion spring 33 urges the member 32 in a counterclockwise direction (as viewed in Figure 3) about pin 29. Member 32 has a notched, latch portion 34, and an extension 36. The latch portion 34 has an inclined face adapted to cooperate with the free end of the blade 19, upward movement of the end of blade 19 being accommodated by a slight clockwise rotation of member 32 and a consequent slight flexing of torsion spring 33.

At the top of housing 1 is a push button assembly 37, comprising a push-button pin 38 which slides within an externally threaded stud 39, which, in turn, is rigidly mounted on the housing 1 by any suitable means, such as the cooperating stud 41. A compression spring 42 housed within the stud 39 urges the push button pin 38 into its outermost position, a retainer 43 serving to define its outward position. The stud 39 cooperates with a nut 40 to mount the timing device on an appropriate mounting panel 45, only an illustrative portion of the panel 45 being shown. The rounded inner end of pin 38 is adapted to cooperate with the extension 36 of the latch member 32, depression of pin 38 resulting in clockwise rotation of member 32 about the pin 29.

In operation, with the parts in the position shown in Figure 3, since contacts 22 and 23 are closed and since the contacts are connected in series with the synchronous motor and its power supply, cam 11 will be rotating clockwise (as viewed in Figure 3). As may best be seen in Figure 4, as cam 11 rotates clockwise beyond its position of Figure 3, the blade 21, riding cam 11, will be raised at its free end and, through contacts 22 and 23, this upward motion will be transmitted to blade 19, cansing the free end of blade 19 to ascend the sloping outer face of the latch portion 34 of member 32. This flexing of blades 19 and 21 caused by cam 11 is localized at the portions 27 and 28 of the blades, their channeled, shank portions completely preventing any longitudinal bowing of the blades even though the central slots in the blades 19 and 21 would otherwise tend to accentuate such bowing deformation.

As cam 11 continues to rotate clockwise, the free end of blade 19 is eventually carried above the notched portion 34 of member 32, whereupon spring 33 drives the portion 34 into latching engagement with blade 19. As cam 11 continues to rotate, the drop-off 10 eventually rides beneath the blade 21, and as blade 21 thereupon drops sharply away, because blade 19 is held by latch member 32, contacts 22 and 23 are abruptly opened. Opening of contacts 22 and 23 stops the motor and consequently the rotation of cam 11. The timing device then remains quiescent until an initiating impulse is provided by depressing the push button 38 to unlatch the blade 19 and close contacts 22 and 23, thereby initiating a timed period which will again terminate, as previously pointed out, when blade 21 falls away from dropoif 10 of cam 11.

Referring now to Figures and 6, which illustrate a modified form of the device just described, parts which find their counterparts in the previously described figures are given corresponding reference numerals but with the prefix 1. The timing device shown in Figures 5 and 6 is adapted for coin actuation and has a coin receptor 61 which cooperates with a coin-chute 62, the timing device being mounted by any suitable means to a panel 145, only a portion of which is shown A latch member 132, has a notched portion 134 and is biased in a counterclockwise direction (as viewed in Figure 5) by a torsion spring 133. The sleeve 131, on which member 132 is mounted, extends somewhat beyond the outer face of the housing and has rigidly attached thereto an elongated actuating lever 63, which may be formed of wire or other suitable material.

The free end of lever 63 is adapted to receive the impact of a coin 64 as it falls through the coin-chute 62.. The coin causes the lever 63 to be rotationally displaced downwardly, and this limited clockwise movement of lever 63 is transmitted to latch member 132 which is correspondingly rotated As viewed in Figure 5, the coin 64 has been inserted in the receptor 61, has traversed the coin-chute 62, and has, through lever 63, moved the latch portion 134 of men.- ber 132 away from the free end of blade 119, allowing contacts i2 2 and 123 to close. Their closure has started rotation of cam 111 clockwise causing the free ends of blades 1]) and 121 to be moved to the left (as viewed in Figure 5). Shortly after the free end of blade 119 has moved past latch portion 134, blade 121 will fall away from the drop-ofi 114) of cam 111, abruptly opening contacts 122 and 123 and terminating the timing period.

The timing device will remain quiescent until a further coin actuated impulse is given to the lever 63 to unlatch 4 the blade 119, permitting the contacts 122 and 123 to reclose and thereby initiate a new timing period.

Referring now to Figures 7 and 8, which illustrate a further modified form of the timing device, parts which find their counterparts in Figures 1, 2, and 3 are given corresponding reference numerals but with the prefix 2.

The modified device shown in Figures 7 and 8 is adapted for manual, rotational actuation. As may be seen in Figure 8, the gear 299, driven by pinion 286, has a conventional frictional driving connection with a sleeve 29-8 which is free to rotate on the central pin 207. Sleeve 208 carries earn 211 and extends through stud 239 to terminate in a flattened portion 71 suitable for mounting of. a control knob. Stud 239 and nut 24% serve to mount the timing device on an appropriate panel 245, only a portion of which is shown.

As will be evident from Figure 7, in this modification of the timing device both blades 219 and 221 ride the periphery of the earn 211, and no separate latching means is provided.

In operation, with the parts in their positions shown in Figure 7, if cam 211 is manually advanced clockwise, by manual rotation of sleeve 208, until blade 219 falls away from drop-off 21d, the contacts 222 and will thereupon abruptly close, starting the timing motor and initiating a timing period. Cam 211 will thereupon be rotated clockwise through the pinion 2-96 and gear 269, and blades 219 and 221 will be moved in unison to the left, as viewed in Figure '7, the contacts 222 and remaining closed. As the drop-off 210 moves under the blade 221, and blade 221 falls away, blade 219 will be held stationary and contacts 2 2 and 22-3 will be obruptly opened. This position of the components is that shown in Figure 7, just after a timing period has been terminated. A new timing period can be initiated by again manually advancing earn 211 clockwise until blade 219 falls away from drop-off 216 which again closes the contacts.

The principal embodiment of the invention and its modifications just described make it apparent that the arrangement whereby the cam can extend through the major plane or" the contact blades permits a compact, yet rugged construction since the blades need not be mounted so as to extend tangent to the cam and the force balancing effect obtained by the straddling of the cam by the blades tends to minimize any torsional deforming forces which exist in the cam and blade assembly. The provision of a stiffened shank and localization of the flexing area of the blades minimizes longitudinal bowing of the blades which, if present to any degree, affects adversely the coaction of the contact blade and the notched latching member. In the present invention the shaping or" the contact blades minimizes the longitudinal bowing of the contact blades and compensates for the weakening of the blades because of the central slots therein through which the cam extends, the blade construction making practical the compact cam and blade assembly.

It will be understood that the actuating cam might be provided with more than one drop-oil portion about its periphery and that other similar modifications may be made without departing from the scope of the invention which is to be limited only by the prior art and defined by the appended claims.

What is claimed is:

l. in a switch construction. the combination of an elongated flexible blade rigidly mounted at one of its ends, an electrical contact carried by said blade, a cam mounted for angular movement adjacent the blade, a longitudinal slot in the blade for accommodating said cam, said slot having one terminal edge adapted to ride the controlling surface of said cam, said cam being adapted to flex said blade to operate the electrical contact upon a predetermined angular movement of said cam.

2. In a switch construction, the combination of an elongated flexible blade rigidly mounted at one of its ends, an electrical contact carried by said blade, a cam mounted for angular movement adjacent the blade, a longitudinal slot in the blade for accommodating said cam, said slot having one terminal edge adapted to ride the controlling surface of said cam, said cam being adapted to flex said blade to operate the electrical contact upon a predetermined angular movement of said cam, and means for localizing the area of flexure of said member.

3. In a switch construction, the combination of an elongated flexible blade rigidly mounted at one of its ends, an electrical contact carried by said blade, a cam mounted for angular movement adjacent the blade, a longitudinal slot in the blade for accommodating said cam, said slot having one terminal edge adapted to ride the controlling surface of said cam, said cam being adapted to flex said blade to operate the electrical contact upon a predetermined angular movement of said cam, said blade having a stiffened central portion for localizing the area of flexure of said member and minimizing the longitudinal bowing thereof.

4. In a switch construction, the combination of an elongated flexible blade rigidly mounted at one of its ends, an electrical contact carried by said blade, a cam mounted for angular movement adjacent the blade, a longitudinal slot in the blade for accommodating said cam, said slot having one terminal edge adapted to ride the controlling surface of said cam, said cam being adapted to flex said blade to operate the electrical contact upon a predetermined angular movement of said cam, said blade having a central channeled portion for localizing the flexure of said blade to an area adjacent said one of its ends and for minimizing the longitudinal bowing of said blade.

5. In a switch construction, the combination of first and second coextensive flexible blades rigidly mounted adjacent one of their ends, cooperating electrical contacts carried by said blades, a cam mounted for angular movement, a longitudinal slot in each of said blades for accommodating said cam, the slot in at least one of said blades having one terminal edge adapted to ride the controlling surface of said cam, said cam being adapted to flex said blades to operate said electrical contacts upon a predetermined angular movement of said cam.

6. In a switch construction, the combination of: first and second coextensive flexible blades rigidly mounted adjacent one of their ends, cooperating electrical contacts carried by said blades, a cam mounted for angular movement, a longitudinal slot in each of said blades for accommodating said cam, the slot in at least one of said blades having one terminal edge adapted to ride the controlling surface of said cam, said cam being adapted to flex said blades to operate said electrical contacts upon a predetermined angular movement of said cam, each of said blades having a central channeled portion for localizing the flexure of said blades to an area adjacent their said mounted ends and for minimizing the longitudinal bowing in each of said blades.

7. In a switch construction, the combination of first and second coextensive flexible blades each having a rigidly mounted portion, cooperating electrical contacts carried by said blades, a cam mounted for rotational movement and adapted to extend through the major plane of said blades, a longitudinal slot in each of said blades for accommodating said cam, the slot in at least one of said blades having an edge portion adapted to ride the periphery of said cam, said cam being adapted to flex said blades to operate said contacts upon a predetermined angular movement of said cam, each of said blades having a stiifened portion for localizing the area of flexure of said blades and minimizing the longitudinal bowing thereof.

References Cited in the file of this patent UNITED STATES PATENTS

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