US3555211A

US3555211A - Thumbwheel type rotary switch with improved manual lever operator

Info

Publication number: US3555211A
Application number: US804834A
Authority: US
Inventors: David Silverman; Robert R Wells
Original assignee: Beckman Instruments Inc
Current assignee: Beckman Industrial Corp
Priority date: 1969-03-06
Filing date: 1969-03-06
Publication date: 1971-01-12
Anticipated expiration: 1988-01-12

Abstract

A rotary switch having a plurality of switch positions and an indicia wheel for visually indicating the switch position. A rotary switch adapted for ganging with a plurality of similar switches to provide multidigit switching capability and a carry function. A manually operated lever for setting the switch to any desired position.

Description

United States Patent 11113,555,211

[ 72] Inventors David Silverman; [56] R n s C t d Robert R. Wells, Anaheim, Calif. UNITED STATES E T 1 1 p 804,334 3,104,299 9/1963 KOCl et a1 200/156 1 1 Filed Mar'61969 3,182,141 5/1965 KOCi et al ZOO/18X [45] Patented Jan-12,19 1 3,236,959 2/1966 Holleman ZOO/17X 1 Asslgnee Baum" l 'l 3,257,535 6/1966 Sallin et a1. 200/156 l 1 3,260,806 7/1966 Jeans 200/17x 3,375,337 3/1968 Barrett et al... ZOO/156 3,435,167 3/1969 Pfleger ZOO/156 Primary Examiner-Robert K. Schaefer Assistant Examiner 1. R. Scott THUMBWHEEL TYPE ROTARY SWITCH WITH Attorneys- Ferd L. Mehlhoff and Robert J. Steinmeyer IMPROVED MANUAL LEVER OPERATOR 13 Claims 12 Drawing ABSTRACT: A rotary switch having a plurality of switch posi- [52] US. Cl 200/17, tions and an indicia wheel for visually indicating the switch 200/1 1,200/ 156 position. A rotary switch adapted for ganging with a plurality [51] Int. Cl HOlh 3/00 of similar switches to provide multidigit switching capability [50} Field of Search 200/1 1, 5, and a carry function. A manually operated lever for setting the switch to any desired position.

l THUMBWIIEEL TYPE ROTARY SWITCH WITH IMPROVED MANUAL LEVER OPERATOR This invention relates to electrical switches and in particular, to rotary type switches having a plurality of switch contacts and an indicia wheel for indicating the switch position. Switches of this general type are being manufactured and used, particularly for setting conditions in electrical circuits corresponding to particular numerical values. A typical rotary switch will provide for connecting an input terminal to any one of different output terminalsby rotation of a contact carrying wheel. The wheel will have the numbers 0 through 9 thereon, with one number visible through an opening in the switch housing indicating the position of the moving contact.

A portion of the wheel projects through an opening of the housing providing for manual actuation of the wheel by a thumb or finger. The switches are adapted for ganging with similar switches to provide a multidigit operation.

Of course, the invention is not limited to any specific contact arrangement or switching combination or number of wheel positions.

The conventional thumb wheel actuated switch has a number of shortcomings. It is hard on the fingertips and is not well suited for continuous operation. The thumb wheel switch is limited with regard to miniaturization because of the essentially fixed size of the human digit. It has been found that it is rather difficult to operate the thumb wheel switches-in the upper direction, while being relatively easy to operate in the downward direction.

Accordingly, it is the object of the present invention to pro 3 provide such a rotary switch including an operating mechanismfor couplingthe lever to the switch to actuate the switch one increment for each lever actuation, and incorv porating a mechanism for accurately each contact position. 7

It is another object of the invention toprovide a new and improved rotary switch mechanism which is adapted for ganging with similar switches and which can include a carry operation to the next higher significant digit and will be either additive or subtractive as required. Such carry operation does not prevent setting of each individual switch.

The invention also comprisesnovel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the'following description. The drawings merely show and the description merely describes preferred embodiments of the present invention which are given by way of illustration or example.

In the drawings:

positioning the switch in FIG. 11 illustrates an alternative fonn of the carry mechanism; and

FIG. 12 illustrates another alternative form of the carry mechanism.

Referring to FIGS. 1-9, the switch includes a housing 20 consisting of a frame 21, a front plate 22, and a side plate 23. Bolts 24 are carried on the front plate 22 for affixing the front plate to the frame 21, using nuts 25 and for mounting the switch in a panel 28, using nuts 29. The side plate 23 is mounted to the frame 21 by a screw 26 which engages a boss 27 projecting into the housing from the frame 21.

The side plate 23 typically is made of an electrical insulating material and carries the electrical conducting surfaces. A typical circuit arrangement is indicated in FIG. 4 and consists of an inner conducting ring 30 and an outer ring of IO equally spaced electrical contacts 31. Each of the contacts 31 and the ring 30 are connected to lead wires 32 for connecting the switch into an electrical circuit.

A wheel 35 is mounted on the boss 27 and carries a plurality of indicia on its outer surface, such as the numbers 0 through 9 corresponding to the ten contacts 31. One indicia is viewed through an opening 36 in the front plate 22 to give a visual indication of the position of the wheel 35. A lens 37 may be positioned in the opening 36 to provide visual magnification and also to provide a closure for the opening.

Thewheel 35 as illustrated, is a molded plastic part, and a conductor 38 is mounted on the wheel for carrying spring contacts 3.9, 40 for completing an electrical circuit between the ring 30 and a selected one of the contacts 31. The construction of the side plate 23, ring 30, contacts 31, wheel 35, plate 38 and

contacts

39, 40 as described thus far, may be conventional. While two

contacts

39, 40 have been illustrated, the switching function could be achieved with the contact 39 and the contacts 31, utilizing the switch housing and component for the ground return, if desired. Other switching arrangements can be used as desired.

Two separate mechanisms are provided for rotating the wheel 35. The switch is designed for ganging with similar switches on both sides, and two such switches are illustrated in FIG. 3. One of the mechanisms for'rotating the wheel provides for wheel rotation as a carry function from a preceding switch. A shaft 43 is mounted in the frame 21, being held in place with a snap ring 44. A coupling member 45 is mounted on a shaft 43 for rotation with respect to the housing, and includes a sprocket gear 46 and a notched wheel or geneva-type gear 47. The gear 46 meshes with another gear 48 mounted on the in dicia wheel 35, for rotating the indicia wheel 35 and the drive wheel 45 in synchronism. The particular geneva wheel 47 il-. lustrated (FIG. 2) has four slots 49 disposed for engagement by a pin 50 carried on the wheel 35 of the adjacent preceding switch.

As used herein, the words following and succeeding refer to the next more significant digit (to the left) and preceding refers to the next less significant digit (to the FIG. 1 is a perspective view of a switch incorporating apreferred embodiment of the invention;

FIG. 2 is a side view of the switch of FIG. 1; FIG. 3 is an enlarged sectional view taken along the line 3-3 of FIG. 2 and showing the switch ganged with a similar switch;

right).

In the particular embodiment illustrated, one full revolution of the wheel 35 of the right-hand switch of FIG. 3 should rotate the wheel 35 of the left-hand'switch one-tenth of one revolution. The ratio between adjacent switches will depend upon the number of switching increments per revolution or the number of the contacts 31. The number of grooves 49 in the wheel 45 and the ratio between the

gears

46 and 48 can be appropriately selected to produce the desired ratio.

A detent mechanism may be provided for the drive wheel 45 and in the embodiment illustrated, comprises a spring 53 held in the frame by a retainer plate 54 and screw 55. The drive wheel 45 has four flat sides, corresponding to the four grooves 49 of the geneva wheel 47, as seen in FIG. 2 and 6. The spring 53 is provided with projecting arms which engage the flat sides of the drive wheel 45 and urge the wheel to one of four angular positions so that the contact 39 is in engagement with one of the contacts 31 when the switch is stationary.

The second mechanism for moving the indicia wheel 35 is a manually operated mechanism provided for setting the switch to a desired position without disturbing adjacent switches (except for carry).

A lever 58 is mounted on a pin 59 carried in the frame 21 and includes an arm 60 projecting outward through an opening 61 in the front plate 22 below the indicia opening 36 (FIGS. and 9). The lever 58 includes stops 62 engaging the frame 21 for limiting upward and downward movement. A de tent or lever centering mechanism is incorporated in the frame for urging the lever to a centered position. Referring to FIG. 9, a compression spring 64 and a ball 65 are positioned in an opening 66 in the frame 21, with the ball 65 engaging a flat surface 67 on the lever 58. A depression may be provided in the surface 67 at the centered position, as illustrated in FIG. 9.

A rearward extension 70 of the lever 58 is fastened to a pawl 71 by a pin 72. The pawl 71 is best seen in FIG. 6 and in the embodiment illustrated includes

fingers

73, 74 with a flat surface 75 there between. A spring 76 is affixed to the pawl 71 and engages the rear wall 77 of frame, urging the pawl into engagement with a pair of the drive pins 80. Alternatively, a spring (not shown) may be affixed to the lever extension 70 or pawl 71 or pin 72 for urging the extension 70 and pawl 71 toward a more acute angle. A plurality of the drive pins 80 is mounted on the wheel 35, and in the embodiment illustrated, pins are equally spaced on the wheel, corresponding to the 10 indicia and 10 switch contacts. The engagement of the pawl 71 with a pair of the pins 80, as illustrated in FIG. 6, provides another detent function.

When the lever arm 60 is moved downward, the pawl 71 is moved upward, bringing the finger 74 into engagement with the pin 80 immediately above the finger, and rotating the wheel 35 counterclockwise, as illustrated in FIG. 7. The pawl 71 includes a surface 81 designed to engage the pin 82 when the wheel 35 has been rotated one increment. This engagement provides accurate positioning of the switch and limits the switch travel for each actuation of the lever arm 60. When the lever arm 60 is released, the detent spring 53 maintains the switch in the new position, while the fcentering spring 64 and ball 65 return the lever and pawl to the centered position of FIG. 6. The downward movement of the lever arm 60 has produced a downward movement of the indicia wheel 35 as viewed at the window 36. Switch actuation one increment at a time may be repeated until the desired switch setting is obtained. The switch is moved in the opposite direction by moving the lever arm 60 upward, moving the finger 73 of the pawl into engagement with a drive pin and rotating the wheel 35 clockwise, as illustrated in FIG. 8. The pawl includes a surface 84, corresponding to the surface 81, for engaging the pin 85 and limiting movement of the switch to one increment. It will be seen that the manual switch setting mechanism permits manual setting of a particular switch without affecting the preceding and following switches in a ganged assembly. The lever mechanism is much easier to actuate than the thumb wheel mechanism and is readily operated in either direction. The lever arm 60 should be of a size adequate for manual actuation. However, the remainder of the switch may be made as small or as large as desired.

While an exemplary embodiment of the invention has been disclosed and discussed, it will be'understood other applications of the invention are possible and that the embodiments disclosed may be subjected to various changes, modifications and substitutions without necessarily departing from the spirit of the invention. By way of example, analternative pawl construction is illustrated in FIG. 10 with

pawls

90, 91 mounted on a lever 92 and urged into engagement with pairs of pins 30 by

spring members

93, 94 respectively. The pawl 91 includes a finger 96 and a surface 97 corresponding to the finger 73 and surface 84, respectively, of the pawl 71. Similarly, the pawl 90 includes a finger 98 and a surface 99 corresponding to the finger 74 and surface 81 of the pawl 71. In the structure illustrated, the lever 92 is mounted on a pin 101 carried on a portion of the frame 21.

An alternative form for the geneva wheel 47 is illustrated in FIG. 11, wherein the grooves or notches are made so large that the remaining portions ofthe wheel appear as fingers MP3. The pin Sill of the wheel 35 moves into the notch between a pair of fingers 103, engaging a finger for rotating the wheel d5 in the same manner as described with the embodiment of FIGS. 1-9. f

Another alternative form for the carry mechanism is illustrated in H6. 12. A projection 105 with a'plurality of gear teeth thereon is provided on the periphery of the wheel 35 in place of the pin 50. A gear 106 i's provided on the drive wheel 45 in place of the geneva wheel 47. W ith this arrangement, the gear segment W5 engages the gear 106 once each revolution of the indicia wheel 35 for one-tenth of a revolution, thereby providing a rotation of the drive wheel in the same manner as in the embodiment of H68. ll-9.

We claim:

1. In a rotary switch for ganging with a plurality of similar switches, the switch including:

a housing;

an indicia wheel rotatably mounted in said housing;

a circuit board mounted in said housing and having at least one conductive surface; at least one electrical contact carried by said wheel for engaging said circuit board, the improvement comprising in combination: 7

a plurality of drive elements mounted on said wheel defining a corresponding plurality of increments of rotation of the wheel;

pawl means mounted in said housing adjacent said wheel and having first and second fingers forengaging said drive elements in wheel driving relationship;

lever means mounted in said housing with one end projecting from said housing for manual actuation and having means coupled to said pawl means for reciprocatingly moving said pawl means in synchronism withsaid lever means, with movement of said lever means in one direction bringing said first of said fingers into engagement with a drive element to rotate said wheel an increment in one direction and with movement of said lever means in the opposite direction bringing said second of said fingers into engagement with a drive element to rotate said wheel an increment in the opposite direction;

a drive wheel rotatably mounted in said housing;

first means for coupling said drive wheel to said indicia wheel; and

second means for coupling said drive wheel to the indicia wheel of an adjacent rotary switch.

2. A switch as defined in claim 1 in which one of said means for coupling provides for simultaneous movement of the coupled wheels, and in which the other of said means for coupling provides for intermittent movement of one coupled wheel with respect to the other.

3. A switch as defined in claim 2 in which said other means for coupling includes a pin on said indicia wheel for engaging a notched wheel of the drive wheel of an adjacent rotary switch.

4. A switch as defined in claim 2 in which said other means for coupling includes a radially projecting section on said indicia wheel occupying substantially one increment for engaging the drive wheel of an adjacent rotary switch.

5. A switch as defined in claim 1 including lever centering means mounted in said housing in engagement with said lever rr'ieans permitting manual actuation of said lever means in opposite direction from a centered position, with said lever-centering means returning said lever means to said centered position when said lever means is manually released.

6. A switch as defined in claim 5 in which said centering means includes a ball and a compression spring, with said spring urging said ball against a substantially flat zone of said lever means to urge said lever means to said centered position.

'7. A switch as defined in claim in which said drive wheel incorporates means defining a plurality of rotational positions for the drive wheel, and in which said switch includes spring means mounted in said housing in engagement with said drive wheel for urging said drive wheel to one of said rotational posiu'ons.

8. A switch as defined in claim 1 in which said pawl means includes a first surface between said fingers for engaging a pair I of adjacent drive elements and a spring'urging said first surface against said pan of drive elements.

9. A switch as defined in claim 8 in which said pawl m includes a second surface adjacent one of said fingers and remote from the other said fingers, for engaging a drive element adjacent the drive element engaged by said one finger, to limit movement of said pawl means and indicia wheel.

10. A switch as defined in claim 1 in which said pawl means comprises a single member with said first and second fingers spaced thereon and engageable with said drive elements of said indicia wheel for driving in opposite directions.

11. A switch as defined in claim 1 in whichsaid pawl means comprises a pair of members, each having one of said fingers thereon, with each of said members engageable with said drive elements of said indicia wheel for driving in one direction.

12. in a rotaryswitch for ganging with a plurality of similar switches, the switch including:

a housing;

an indicia wheel rotatably mounted on said housing,

a circuit board mounted in said housing and having at least one conducting surface;

at least one electrical contact carried by said wheel for engaging said circuit board, the improvement comprising in combination:

a plurality of drive pins mounted on said wheel defining a corresponding plurality of increments of rotation of the wheel;

a pawl mounted in said housing adjacent said wheel and having first and second fingers for engaging said drive elements in wheel driving relation, said pawl having a centered position with said fingers out of engagement with said pins pennitting rotation of said indicia wheel;

a lever mounted in said housing with one end projecting from said housing for manual actuation and having means coupled to said pawl for reciprocatingly moving said pawl in opposite directions from said centered position in synchronism with said lever;

with movement of said lever in one direction bringing one of said fingers into engagement with a drive pin to rotate said wheel an incrementin one direction and with movement of said lever in the opposite direction bringing the other said fingers into engagement with a drive pin to rotate said wheel an increment in the opposite direction; 1 a drive wheel rotatably mounted in said housing; first means for coupling said drive wheel to said indicia wheel; and second means for coupling said drive wheel to the indicia wheel of an adjacent rotary switch.

13. A switch as defined in claim 12 in which said switch includes a shaft mounted in said housing and said first means for coupling comprises meshing gears mounted on said shaft and indicia wheel and said second means for coupling comprises a pin mounted on said indicia wheel for engaging a notched wheel carried on the shaft of the adjacent switch.

Claims

1. In a rotary switch for ganging with a plurality of similar switches, the switch including: a housing; an indicia wheel rotatably mounted in said housing; a circuit board mounted in said housing and having at least one conductive surface; at least one electrical contact carried by said wheel for engaging said circuit board, the improvement comprising in combination: a plurality of drive elements mounted on said wheel defining a corresponding plurality of increments of rotation of the wheel; pawl means mounted in said housing adjacent said wheel and having first and second fingers for engaging said drive elements in wheel driving relationship; lever means mounted in said housing with one end projecting from said housing for manual actuation and having means coupled to said pawl means for reciprocatingly moving said pawl means in synchronism with said lever means, with movement of said lever means in one direction bringing said first of said fingers into engagement with a drive element to rotate said wheel an increment in one direction and with movement of said lever means in the opposite direction bringing said second of said fingers into engagement with a drive element to rotate said wheel an increment in the opposite direction; a drive wheel rotatably mounted in said housing; first means for coupling said drive wheel to said indicia wheel; and second means for coupling said drive wheel to the indicia wheel of an adjacent rotary switch.

5. A switch as defined in claim 1 including lever centering means mounted in said housing in engagement with said lever means permitting manual actuation of said lever means in opposite direction from a centered position, with said lever-centering means returning said lever means to said centered position when said lever means is manually released.

7. A switch as defined in claim 2 in which said drive wheel incorporates means defining a plurality of rotational positions for the drive wheel, and in which said switch includes spring means mounted in said housing in engagement with said drive wheel for urging said drive wheel to one of said rotational positions.

8. A switch as defined in claim 1 in which said pawl means includes a first surface between said fingers for engaging a pair of adjacent drive elements and a spring urging said first surface against said pair of drive elements.

9. A switch as defined in claim 8 in which said pawl means includes a second surface adjacent one of said fingers and remote from the other said fingers, for engaging a drive element adjacent the drive element engaged by said one finger, to limit movement of said pawl means and indicia wheel.

11. A switch as defined in claim 1 in which said pawl means comprises a pair of members, each having one of said fingers thereon, with each of said members engageable with said drive elements of said indicia wheel for driving in one direction.

12. In a rotary switch for ganging with a plurality of similar switches, the switch including: a housing; an indicia wheel rotatably mounted on said housing, a circuit board mounted in said housing and having at least one conducting surface; at least one electrical contact carried by said wheel for engaging said circuit board, the improvement comprising in combination: a plurality of drive pins mounted on said wheel defining a corresponding plurality of increments of rotation of the wheel; a pawl mounted in said housing adjacent said wheel and having first and second fingers for engaging said drive elements in wheel driving relation, said pawl having a centered position with said fingers out of engagement with said pins permitting rotation of said indicia wheel; a lever mounted in said housing with one end projecting from said housing for manual actuation and having means coupled to said pawl for reciprocatingly moving said pawl in opposite directions from said centered position in synchronism with said lever; with movement of said lever in one direction bringing one of said fingers into engagement with a drive pin to rotate said wheel an increment in one direction and with movement of said lever in the opposite direction bringing the other said fingers into engagement with a drive pin to rotate said wheel an increment in the opposite direction; a drive wheel rotatably mounted in said housing; first means for coupling said drive wheel to said indicia wheel; anD second means for coupling said drive wheel to the indicia wheel of an adjacent rotary switch.