US2824176A

US2824176A - Calling device identification cam assembly

Info

Publication number: US2824176A
Application number: US616204A
Authority: US
Inventors: Joseph M Hartz
Original assignee: General Telephone Laboratories Inc
Current assignee: General Telephone Laboratories Inc
Priority date: 1956-10-16
Filing date: 1956-10-16
Publication date: 1958-02-18
Anticipated expiration: 1975-02-18

Description

Feb. 18, 1958 w ll J. M. HARTZ 2,824,176

CALLING DEVICE IDENTIFICATION CAM ASSEMBLY File Oct. 16, 1956 FIG. 2 l0 FIG.3

' -INVENTOR.

JOSEPH a HARTZ ATTY.

United States Patent CALLING DEVICEIDENTIFICATION CAM ASSEMBLY Application October 16, 1956, Serial No. 616,204 Claims. Cl. 119-90 This invention relatesto calling devices of the impulse transmitting type and more particularly to improvements in party identification cam arrangements adapted for use in such calling devices. The calling. device of the character in which the use of the present invention is contemplated and over which it represents. an. improved arrangement is well-known in the artand is described for example, in U. S. Patent No. 2,366,647, John E. Ostline, granted January 2, 1945. It is also an improvement of the pending application to John E. Ostline, Serial No. 472,713, filed December 2, 1954. In the patent cited and the pending application is shown, in addition to the obvious impulsing and shunting springs, a pair of supplemental impulsing springsoperated periodically by a cam affixed to, and rotating with the main dial arbor. The lobe or lobes of said cam are sopositioned, with respect to the supplemental impulsing spring operating pawl, that the latter springs willmake contact at. a time having a predetermined relationship to the closing of the digit impulsing springs as operated by the digit impulse spindle and cam. I I t a It is evident from the arrangements shown in the cited patent and application; thatthe angular positioning of the supplemental impulsing cam,is ,highly critical ifthe predetermined relationship referred to is to be accurately maintained. The method of shifting the cam lobes in the patent depends for its accuracy in locating the lobes largely upon trial and error. In the pending application the accuracy depends on the tightening of three separate screws for securely holding the cam in a certain location.

It is the chief object of my invention to provide an identification cam assembly for a calling device in which the locating plate is held by a single nut.

A feature of my invention is that the locating plate is positively located with respect to the finger wheel and the impulse cam.

Another feature of my invention is the dual function of the slot in the drive shaft to prevent rotation of the coil spring and locating plate.

A still further feature of my invention is to positively locate the indicia plate with respect to the impulse pawl.

Fig. 1 is a plan view of the rear of a dialing device showing the relative positions of the contact springs and the two operating cams,

Fig. 2 is a side elevation of the dialing device showing clearly the pair of supplementary impulsing springs and their relation to the main dial arbor operating cam,

Fig. 3 is an enlarged plan view of the identification cam assembly showing the supplementary contact springs and cam arrangement, the operating means employed to accuate the springs, and the cam lobe locating means,

Fig. 4 is a sectional view along the line 4-4 of Fig. 3 showing the relative positions of the details of the identification cam assembly, and

Fig. 5 is a view of the indicia plate illustrating the opening in the center of the plate in the shape of two segments of a circle with a bar between.

A dialing device embodying my invention and shown 'ice in Figs. 1 and 2. includes a mechanism housing 10 and finger wheel 11 and dial plate 12 which may be operatively secured to the housing 10 and its contained mechanism (not shown) in a well-known manner. A main shaft 13 rotatably mounted in the housing 16 is rotatable with the fingerwheel 11 and carries the identification cam assembly to be described in detail hereinafter. The coil spring 14 aifixed at one end to the housing 10 and at the other end to the shaft 13 insures the return to a normal position of the finger wheel 11 after it has been rotated a predetermined amount. A spindle 15 extends outside the housing 10 parallel to the shaft 13 and is controlled by the mechanism to rotate only upon the release of the finger wheel 11 when the finger wheel. 11 is permitted to return to its normal position. An impulse cam 16 is rigidly secured to the spindle 15. A centrifugal governor 18 mounted on the housing 10 is associated with a gear 19, which is mounted on spindle 15, to maintain the rotational speed of the cam 16 within predetermined limits in awell-known manner.

Mountedon the housing 10 in a conventional manner are a number of operating spring assemblies. Two of these springs, 20 and 21, are impulsing springs operatively associated with a pair of lobes 22 of the impulsing cam 16. p

A pair of supplementary impulsing

springs

30 and 31 cooperate with the identification cam assembly. The

shaft 13,, slotted and threaded at one end, is journalled in a guide bushing 36 afiixed to the housing 10. A second bushing 37, mounted on the shaft 13, is part of the rotatable spring assembly. This spring assembly consists ofthe spring 14, a bushing 37 with a washer 33 clamping oneend of the spring 14, is seated on an annular shoulder provided .on the bushing 3'7, and supported by the washer 39 is an annularcam mounting plate 38 rigidly mounted on the bushing 37 by upsetting the upper portion 51 of the bushing 37. The end of the spring 14 projects through the slot 50 in the end of shaft 13. Concentric with the annular mounting plate 38 andthe arbor 13 is an insulated annular cam 40 resting on plate 38 and having its peripheral portion extending beyond the plate 38. A cam lobe 41. is provided on the periphery of the cam 40. Although only one lobe is shown it is to be understood that any number of such lobes may be provided as may be required for identification purposes. A circular dish shaped locating plate 43, having in its center two segments of a half circle with a bar separating them, rests on the cam 40. The locating plate 43 is centered by the bar 49 engaging the slot 50 of the shaft 13. This locating plate is provided with locating means 45 which may comprise peripheral notches as shown in Fig. 5. The cam lobe or lobes 41 may be rotated about the upset portion. of bushing 37 to a position or positions directly opposite any one or more of the notches 45. The indicia 46 indicating the notches 45 may be provided on the surface of the plate 43 to facilitate the location of the required lobe position. The locating plate cannot rotate to get out of correct alignment of the notches 45 of the plate 43 with respect to the pawl 32 because of the bar 49 in the slot 50 of the shaft 13. The tightening of nut 48 on the dish shaped indicating plate 43 clamps the cam 40 to the plate 38. The clamping takes place at the periphery of the indicating plate due to its dish shaped contour. The indicating plate is always in perfect alignment with respect to pawl 32, and it leaves only the lobe 41 of the cam 43 to be aligned with the notch in the plate 43 before tightening nut 48.

Returning now to the operation of the dialing device: as the finger wheel 11 is rotated from its normal position to its extreme rotatable position, that is, to a position corresponding to the 0 digit of a conventional dialing closing of the impulsing

springs

20 and 21.

device, the springs 24 and 21 are moved into a cooperative relationship with the impulse cam 16. When the finger wheel 11 is released, the impulse cam is caused to rotate, the cam lobes 22 alternately engaging the spring 2t) thereby periodically opening the impulse springs 20 and Zll. The lobe 41 and the cam 40 may be shifted to any angular position, by releasing the nut 48, so that the supplementary

impulsing springs

30 and 31 will close at any time with respect to the timing of the opening and The notches 45, ten in number, are therefore spaced around the periphery of the locating plate 43, and the locating plate 43 is so located positively bythe bar 49, that the shifting of the cam lobe 41 to any position opposite any of notches 45 will cause the operation of supplementary impulsing

springs

30 and 31 to fall at a certain time between the operations of the imposing springs 2t) and Zll.

The advantages of the cam assembly according to my invention is the simplicity of changing the position of the lobes 41 with respect to the notch 45 by the loosening and the tightening of one nut 48. The tightening of the nut 48 also clamps the end of the spring 14 in the slot 50 of the shaft 13.

What is claimed is:

1. In a dialing device, an impulse generator comprising a rotatable shaft, a finger wheel mounted at one extremity of said shaft for manually rotating said shaft, a mounting plate mounted near the other extremity of said shaft and rotatable with said shaft, a slot in the end of said shaft, a cam adjustably supported on said mounting plate, means for clamping said cam to said mounting plate, said clamping means having perforations in the center thereof, said perforations being segments of a circle separated by a bar, said bar engaging the slot of said shaft to prevent rotation about said shaft of said clamping means.

2. A dialing device as claimed in claim 1, in which said clamping means comprises a dish shaped element, and in which there is a nut threaded on said slotted portion of said shaft to clamp the dish shaped clamping means to said cam.

3. In a dialing device, an impulse generator comprising a rotatable shaft, a finger wheel mounted at one end of said shaft for manually rotating said shaft, a slot in the other end of said shaft, a mounting means near the slotted end of said shaft and perpendicular thereto, a cam adjustably supported on said mounting means, a pair of contact springs, one of said springs having means thereon for cooperating with said cam, a dish shaped clamping plate having indicating means thereon, means for clamping said plate to said cam, said clamping plate having perforations in the center thereof, said perfora tions being segments of a circle separated by a bar, said bar engaging the slot of said shaft, said bar in said slot aligning the indicating means on said clamping plate with the means on said one spring for cooperating with said cam.

4. In a dialing device, an impulse generator comprising a rotatable shaft, a finger wheel mounted at one extremity of said shaft for manually rotating said shaft, a slot in the other end of said shaft, a mounting plate rotatable with said shaft, a spiral spring for controlling the rotation of said shaft and having one end of said spring projecting through the slot in said shaft, a cam supported on said mounting plate, a dish shaped indicia plate in contact with said cam, said indicia plate having perforation in the center thereof, said perforations being segments of a circle separated by a bar, said bar engaging the slot of said shaft to prevent independent rotation thereof, means on said shaft to clamp said dish shaped indicia plate to said cam and prevent said spiral spring from disengaging said slot.

5. In a dialing device, an impulse generator comprising a housing with a shaft rotatably mounted therein, a finger wheel rigid with one end of the shaft for rotating the same, a slot in the other end of the shaft, a power spring having one end secured to the housing and the other end passing through said slot to return the shaft after rotation by said wheel, a plate rigidly mounted near the slotted end of the shaft, a cam adjacent said plate on said shaft, said cam having a lobe and said cam being rotatable to adjust the position of the lobe, a clamping washer adjacent said cam on the shaft and having a key registering with the slot in said shaft to rigidly locate the washer against rotation on the shaft, and means for clamping said washer against said cam to lock the cam in place and clamp the end of said power spring in said slot.

No references cited.