US3861238A

US3861238A - Adjustable time timing gear for timing apparatus

Info

Publication number: US3861238A
Application number: US364732A
Authority: US
Inventors: Robert W Christianson
Original assignee: Whirlpool Corp
Current assignee: Whirlpool Corp
Priority date: 1973-05-29
Filing date: 1973-05-29
Publication date: 1975-01-21
Anticipated expiration: 1992-01-21

Abstract

A driving gear is adjustable along the longitudinal axis of its supporting shaft to a plurality of positions. The gear has different numbers of teeth at the various positions so that positioning of the cam on its shaft determines the gear ratio between the driving gear and a driven gear.

Description

United States Patent [191 Christianson Jan. 21, 1975 ADJUSTABLE TIME TIMING GEAR FOR TIMING APPARATUS [75] Inventor: Robert W. Christianson, St. Joseph,

Mich.

[73] Assignee: Whirlpool Corporation, Benton Harbor, Mich.

22 Filed: May 29,1973

[21] Appl. N0.: 364,732

[52] U.S. Cl. 74/568 T, 74/3.5, 74/435 [51] Int. Cl. Fl6h 53/00 [58] Field of Search 74/3.5, 325, 352, 431,

74/432, 434, 435, 337, 421, 568 T, 460, 468, 640; 200/38 A, 38 R, 35 R; 58/7, 8, 23 D, 28

[56] References Cited UNITED STATES PATENTS 2,874,809 2/1959 Poole 74/435 X Hall 74/568 T Cartier 74/568 T Primary Examiner-Benjamin W. Wyche Assistant ExaminerFrank H. McKenzie, Jr. Attorney, Agent, or Firm-Hill, Gross, Simpson, Van Santen, Steadman & Chiara [5 7] ABSTRACT A driving gear is adjustable along the longitudinal axis of its supporting shaft to a plurality of positions. Thegear has different numbers of teeth at the various positions so that positioning of the cam on its shaft determines the gear ratio between the driving gear and a driven gear.

15 Claims, 5 Drawing Figures ADJUSTABLE TIME TIMING GEAR FOR TIMING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to. an adjustable time timing gear, and more particularly to a timing gear carried on a supporting shaft and having means for releasably locking the gear at selected positions longitudinally of the supporting shaft.

2. Description of the Prior Art It is well known in the art to provide different gear ratios between a driving gear and a driven gear by changing the number of teeth presented by one gear to the other. For example, U.S. Pat. No. 2,328,473 discloses a traffic signal controller or timer which employs a pinion for driving a selected gear of a cone gear. The desired gear ratio is obtained by pivoting the pinion to disengage from the cone gear, sliding the pinion and its prime mover longitudinally of the cone gear on a sepa rate shaft parallel thereto and then pivoting the pinion to again engage the cone gear. U.S. Pat. No. 2,907,221 discloses the use of a cone gear as the driving gear for selective engagement with a pinion as the driven gear. Selective engagement at different gear ratios is provided by means of a cam and lever arrangement which positions the pinion longitudinally of the cone gear. Each of the foregoing types of apparatus for providing different gear ratios involves the provision and use of additional levers, shafts and/or cam mechanisms for positioning one of the gears with respect to the other, both longitudinally of the axis of one of the gears and radially with respect to the axis of the cone gear due to the stepped configuration of a cone gear.

U.S. Pat. No. 3,075,055 discloses a control member which functions as a timing gear for driving a toothed wheel at different rates. The control member has a plurality of spaced teeth about the circumference thereof, which teeth are radially displaceable for selective engagement with or bypassing of the teeth of the driven toothed wheel. The movable teeth may therefore be radially displaced in selected patterns to provide the various rates of revolution of the toothed wheel. Although this structure eliminates the aforementioned disadvantage of moving one gear radially with respect to the other, the provision of additional parts in the form of movable teeth is in itself a disadvantage.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a timing gear arrangement which is easily adjustable to provide a plurality of gear ratios between a driving gear and a driven gear.

Another object of the invention is to provide an adjustable time timing gear arrangement in which the selection of gear ratios is accomplished by movement of one gear with respect to the other only in the longitudinal direction of its axis.

Another object of the invention is to provide a longitudinally adjustable gear having different numbers of teeth at different positions along its axis which teeth have the same mean diameter.

Another object of the invention is to provide a simple means for releasably engaging the adjustable gear at different positions longitudinally of its supporting shaft.

Another object of the invention is to eliminate the great number of piece parts which were necessary in prior arrangements for providing different gear ratios and to provide an adjustable timing gear which is selectively and releasably engaged at positions along its supporting shaft, wherein the gear, the shaft and the means for releasably engaging the gear and the shaft are provided by only two piece parts.

A gear is provided with a plurality of gear sections at different positions along its longitudinal axis. At these positions the gear has different numbers of teeth, all of which have the same mean diameter so that longitudinal movement of the gear, parallel to the axis of rotation of the gear mated therewith, changes the gear ratio. The gear is molded from a plastic material as a single piece part. By the same token, the supporting shaft for the gear is molded of plastic material and includes a plurality of resilient locking tabs for releasably engaging the gear at the different gear ratio locations.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the invention, its organization, construction and operation will be best understood from the following detailed description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, on which:

FIG. 1 is a pictorial view, shown partially broken away, of a coin-operated clothes dryer as an exemplary environment for a timer employing the present invention;

FIG. 2 is an end view of a timer constructed in accordance with the principles of the present invention;

FIG. 3 is a view similar to FIG. 2 showing the timer in an operating condition;

FIG. 4 is a pictorial representation of apparatus constructed in accordance with the present invention; and

FIG. 5 is a sectional view taken generally along the line V-V of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiment of the invention is illustrated in FIG. 1 in the environment of a commercial clothes drying appliance 10 which comprises an enclosure cabinet 12 having a console 14 thereon. The console 14 comprises a coin box 17 having a slide-type coin slot device 18, and houses a timing device 16 for regulating the drying operation. The enclosure cabinet 12 further comprises horizontal top and

bottom panels

20 and 22, respectively, a pair of vertical side panels 24, only one of which can be seen on the drawing, and vertical front and

rear panels

26 and 28, respectively. The enclosure cabinet 12 further comprises an access opening 30 in the front panel 26, as defined by an inturned flange 31. The access opening 30 has a closure door 32 cooperating therewith for loading and unloading the dryer 10.

The dryer 10 further includes a drying container for tumbling clothes in the form of a revolving drum 34 housed within the cabinet 12 and extending axially from the front panel 26 to a bulkhead 36 spaced forwardly of the rear panel 28. In order to promote a tumbling action of the clothing being dryed, a plurality of circumferentially spaced baffles 78 (one being illustrated on the drawing) are mounted on the inner surface of the drum 34. The drum 34 includes a radially inward extending front closure wall 41 having an access opening 42 therein formed by means of an axially outturned flange 43. The flange 43 provides a forwardly extending annular bearing which overlies and is suitably journaled on the complementary flange 31 of the enclosure cabinet 12. It will be apparent from the foregoing description that the opening 42 into the drum 34 and the opening 30 formed in the front panel 26 are concentric, providing access into the rotatable drum 34 from the outside of the cabinet 12. The drum 34 is supported at the rear by a pair of support rollers 48 (one being illustrated on the drawing) mounted on the bulkhead 36. A raceway or circumferential groove 50, formed as a circumferential indentation in the peripheral wall of the rear portion of the drum 34 serves as a track for the rollers 48.

The appliance also comprises a motor 52 mounted on the bottom panel 22 in a rear corner of the cabinet 12 which rotatably drives the drum 34 by means of a drive belt 54 extending around the periphery of and in frictional engagement with the drum 34 and around a motor pulley 56 mounted at one end of a motor shaft 58. The other end of the motor shaft 58 is connected to drive a blower 60 which is arranged to circulate air through the drum 34. The blower 60 is included in a warm air system 62 positioned between the rear panel 28 and the bulkhead 36.

The bulkhead 36 serves to enclose an open-ended rear portion of the drum 34 and provides a fixed rear wall in which is located a pair of spaced openings which are covered by respective perforate sections to provide an air inlet 64 and an air outlet 66. The blower 60 draws moisture-laden air from the interior of the drum 34 through the air outlet 66, through a removable lint screen 68, through an air duct 70 and exhausts the air out of the cabinet 12 through an exhaust duct 72. Air exhausted from the drum 34 is replaced by ambient air entering the warm air system 62 by way of an intake opening in rear panel 28 (not shown) and passes over a heater means 76 as it is drawn through a fresh air duct 74 and into the drum 34 through the air inlet 64. The warm air system 62 thus circulates a stream of warm air through the drum 34, subjecting the clothing placed therein to a drying environment to remove moisture from the fabrics while the clothing is tumbled as the drum 34 rotates.

Referring to FIGS. 2 and 3, the timing device 16 of FIG. 1 is illustrated in greater detail. The timing device 16 has

encasement wall members

90 and 91 which enclose the timing mechanism. A lever 100 is actuated through the movement of the coin slot device 18. When actuated the lever 100 rotates about a pin 92 and when released rotates under the bias caused by a spring 93 back to its original or returned position. It should here be noted that it is common practice in laundry establishments to provide a certain amount of drying time in return for a certain denomination of coin inserted into the coin mechanism and to provide multiples of such drying time for each multiple of such denomination, i.e., for each actuation of the lever 100. The lever 100 acts through a ratchet wheel or one way clutch mechanism 101 to rotate a face cam 102 in the direction shown by the arrow when the lever is released to return to its original position. A face cam 103 is splined through a pair of telescopically related

spline collars

104, 106 to a gear 105. The gear 105 is frictionally engaged by a detention spring member 110 so that rotation of the gear 105 is resisted. Therefore, when the face cam 102 is rotated by the lever 100, the cam 103 does not at first rotate, but is forced away from the cam 102 by the action of the respective camming surfaces 112 and 1 l 1 against the spring bias of a pair of

switches

115 and 116. The

cams

102 and 103 move in opposite directions axially of the shaft 92 in two steps, thereby first actuating the switch 115 and then actuating the switch 116. The switch 115 actuates the drive motor 52 and a timing motor 117 and the switch 116 actuates the heater 76. When the cam 103 has been rotated to the position shown in FIG. 3, the two

cams

102, 103 lock together by the action of a locking surface 113 on the cam 102 on a locking surface 114 on the cam 103. Any further rotation of the cam 102, as may be effected by the insertion of additional coins and movement of the lever 100, causes both the cam 102 and the cam 103 to rotate together by overcoming the friction of the spring on the gear 105. This further rotation of the cams also causes a pin 107 on the gear 105 to begin to separate from a pin 109 on a star wheel 108. FIG. 2 illustrates the pins before rotation of the cam 103, while FIG. 3 shows the pins after rotation of the cam 103. The timer 117 acts through a shaft 121 to rotate a timing gear 120 to rotate the star wheel 108. After actuation of the timer motor 117 by switch 115, the star wheel 108 will be rotated by timing gear 120 to drive the pin 109 until contact with the pin 107 is made. At this point, the star wheel 108 will begin to rotate the cam 103 with respect to the cam 102, the latter being held stationary by the ratchet mechanism 101 when the lever 100 is in the returned position. Rotation of the cam 103 with respect to the cam 102 will cause a time period to elapse and then the cams will move toward each other in two steps as the cam surface 112 rotates back into contact with the cam surface 111. The first step will deactivate the heater 76 by permitting the switch 116 to restore under the influence of its spring bias, and the second step will deactivate the drive motor 52 and the timer motor 117 by permitting restoration of the switch under the control of its bias. This sequence provides for a cool down at the end of each cycle, regardless of how many coins are inserted to lengthen the drying time by arcuately separating the

pins

107 and 109.

Referring now to FIGS. 4 and 5, the timing gear 120 is illustrated in greater detail. The gear 120 comprises a generally cylindrical member having rounded teeth, the number of teeth varying along the longitudinal axis of the gear. By positioning the gear 120 on a supporting shaft 121 so that a given number of teeth will engage the star wheel 108, the amount of drying time to be provided for the number of coins inserted can be selected in that the number of revolutions of the gear 120 per revolution of the star wheel 108 can be selected.

The gear 120 is releasably locked into position on the shaft 121 by one or more of a plurality of

tabs

122, 123, 124, and 126, which extend at an acute angle with respect to the surface of the shaft 121, as illustrated in FIGS. 4 and 5. The shaft 121 and the tabs 122-126 are molded as a single part, as is the gear 120. The shaft 121 is driven by the timer motor 117 by way of a shaft 118. As shown on the drawing, there are five possible positions of the gear 120 on the shaft 121, in this particular exemplary embodiment. The possible positions allow for 8, 6, 12, 4 or 9 teeth to drivingly engage the teeth of the star wheel 108. In FIGS. 4 and 5, the gear 120 is in the position for 12 teeth to engage the star wheel 108. This would provide, for example, fifteen minute timing increment for each actuation of lever 100. To provide a 45 minute increment, the gear 120 is moved outwardly on the shaft to a position for four teeth, by depressing the locking tab 124 and moving the gear toward the locking tab 123. The tabs 122-126 are resilient so that when the gear 120 is moved in the direction of the arrow shown on the shaft 121, the tab 126 moves upwardly, as viewed in FIG. 5, so that the gear 120 is grasped between the

tabs

124 and 126. To provide a minute increment, the cam is moved to the position for nine teeth by pressing the locking tab 123 and moving the gear 120 out to abut the tab 122. The gear 120 will then be releasably locked between the

tabs

122 and 125.

To provide a 22 /2 minute increment, the gear 120 is moved to the position for eight teeth by depressing the locking tab 122, removing the gear 120 from the shaft 121, reversing the ends of the gear 120 and placing the gear back on the shaft until it is locked between the

tabs

122 and 125. To provide a 30 minute increment, the gear 120 is moved to the position for six teeth by depressing the locking tab 125 and pushing the timing cam in the direction opposite to that of the arrow until it is locked between the

tabs

123 and 126. The gear 120 therefore provides five variable time periods, in this particular embodiment, that can be selected for a timing mechanism to vary the gear ratio between the gear 120 and the driven wheel, in this case the star wheel 108.

The simplicity in changing the gear ratio is readily apparent from the foregoing description and the associated figures of the drawing. Therefore, the owner, or maintenance personnel, of a commercial laundry establishment can easily select gear ratios for the timing mechanism and is therefore provided with an additional degree of flexibility in relating coins and drying times.

Although I have described my invention by reference to a particular illustrative embodiment thereof, many changes and modifications of the invention may become apparent to those skilled in the art without departing from the spirit and scope of the invention. I therefore intend to include within the patent warranted hereon all such changes and modifications as may reasonably and properly be included within the scope of my contribution to the art.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a timer apparatus of the type wherein a control mechanism is coupled to be driven by a motor via a gear train including first and second meshed gears, the improvement therein of means for varying the gear ratio of said first and second gears to vary the rate at which said motor drives said control mechanism, wherein:

said first gear including at least two sections at positions along its axis of rotation, each section including a different number of teeth and the teeth of each section providing the same mean diameter for said first gear as the teeth in each other section; and

locking means for selectively and releasably locking one of said gears at positions along its axis of rotation to selectively mesh the teeth of said first gear with the teeth of said second gear at different gear ratios.

2. The improvement in timer apparatus, as set forth in claim 1, wherein said first gear is mounted for rotation on a supporting shaft and said locking means includes a plurality of resilient tabs spaced along and extending from said supporting shaft for engaging a face of said first gear when such face is positioned adjacent thereto.

3. The improvement in timer apparatus, as set forth in claim 2, wherein said shaft and said tabs are formed as a unitary structure.

4. The improvement in timer apparatus, as set forth in claim 2, wherein said tabs extend at an acute angle with respect to the surface of said supporting shaft.

5. The improvement in timer apparatus, as set forth in claim 4, wherein a first group of said tabs are directed toward one end of said supporting shaft and a second group of said tabs are directed toward the other end of said supporting shaft so that said first gear may be locked between a tab of said first group and a tab of said second group.

6. Timer apparatus comprising:

a motor;

a first shaft connected to and rotated by said motor;

a first gear carried on said first shaft for rotation therewith, said first gear including sections axially thereof having different numbers of teeth,

said first gear having the same mean tooth diameter at all said sections;

a second shaft mounted for rotation;

a control mechanism connected to said second shaft and operated by the rotation thereof to perform at least one control operation;

a second gear having teeth engaged with teeth of said first gear and carried on said second shaft for rotating said second shaft,

one of said gears fixed to its respective shaft and the other of said gears being axially movable along its respective shaft; and

locking means for locking said axially movable gear at a selected position on its respective shaft for selecting the gear ratio between said first and second gears and the rate of operation of said control mechanism.

7. The apparatus according to claim 6, wherein said locking means includes spaced, resilient tabs extending from the shaft which carries the axially movable gear.

8. The apparatus according to claim 7, wherein said tabs and said shaft which carries the axially movable gear are constructed as a single unitary structure.

9. The apparatus according to claim 7, wherein said tabs extend at an acute angle with respect to the surface of the shaft which carries the axially movable gear.

10. The apparatus according to claim 7, wherein a first group of said tabs extend at an acute angle from the surface of and are directed toward one end of the shaft which carries the axially movable gear, a second group of said tabs extend at an acute angle from the surface of and are directed toward the other end of the shaft which supports the axially movable gear, and the axially movable gear may be positioned and releasably locked between a tab of said first group and a tab of said second group.

11. For use in a coin-operated laundry appliance of the type having a rotatable clothes receptacle, means for treating clothes within the receptacle and a coinoperated timing device, said timing device comprising:

a rotatable shaft; means operable upon the insertion of coins of a predetermined denomination to rotate said shaft in a first direction;

a motor operable to rotate said shaft in the opposite direction;

means coupled to said shaft for controlling the operation of said means for treating clothes;

a gear train driven by said motor and connected to said shaft and including a first gear having a plurality of gear sections disposed along its longitudinal axis, each of said sections including different numbers of teeth and all sections having the same mean tooth diameter,

a second gear having teeth engageable with the teeth of said first gear, and

means for providing relative longitudinal movement between said two gears and releasably and selectively locking said two gears with respect to said longitudinal movement to provide a selected gear ratio therebetween.

12. In a dryer having a coin-operated control mechanism, said mechanism having a motor and means including a driven gear driven by said motor for controlling timing operations of said dryer, an adjustable gear driven by said motor for varying the rate at which said motor drives said means for controlling the timing operations of said dryer, said adjustable gear comprising:

an essentially cylindrical member, a first plurality of teeth circumferentially protruding from said member, a second plurality of teeth circumferentially protruding from said member, said second plurality of teeth being longitudinally spaced at a distance from said first plurality of teeth, locking means for locking said member in a position for engagement of one of said first and second pluralities of teeth with said driven gear, whereby the positioning of said gear for engagement with said driven gear determines the rate at which said motor drives said means for controlling timing operations of said dryer.

13. In a dryer according to claim 12, comprising a first shaft carrying said cylindrical member, a second shaft extending parallel to said first shaft and carrying said driven gear; and wherein said locking means comprises a plurality of resilient locking tabs carried by one of said shafts.

14. In a dryer according to claim 12, comprising a shaft carrying said cylindrical member, said locking means including a plurality of resilient tabs extending from said shaft.

15. In a dryer according to claim 14, wherein said plurality of resilient tabs are divided into two groups, the tabs of a first of said groups extending at an acute angle from the surface of and directed toward one end of said shaft and the tabs of the second group extending at an acute angle from the surface of and directed toward the other end of said shaft, said cylindrical member being axially movable and releasably locked between a tab of the first group and a tab of the second group.

Claims

1. In a timer apparatus of the type wherein a control mechanism is coupled to be driven by a motor via a gear train including first and second meshed gears, the improvement therein of means for varying the gear ratio of said first and second gears to vary the rate at which said motor drives said control mechanism, wherein: said first gear including at least two sections at positions along its axis of rotation, each section including a different number of teeth and the teeth of each section providing the same mean diameter for said first gear as the teeth in each other section; and locking means for selectively and releasably locking one of said gears at positions along its axis of rotation to selectively mesh the teeth of said first gear with the teeth of said second gear at different gear ratios.

6. Timer apparatus comprising: a motor; a first shaft connected to and rotated by said motor; a first gear carried on said first shaft for rotation therewith, said first gear including sections axially thereof having different numbers of teeth, said first gear having the same mean tooth diameter at all said sections; a second shaft mounted for rotation; a control mechanism connected to said second shaft and operated by the rotation thereof to perform at least one control operation; a second gear having teeth engaged with teeth of said first gear and carried on said second shaft for rotating said second shaft, one of said gears fixed to its respective shaft and the other of said gears being axially movable along its respective shaft; and locking means for locking said axially movable gear at a selected position on its respective shaft for selecting the gear ratio between said first and second gears and the rate of operation of said control mechanism.

11. For use in a coin-operated laundry appliance of the type having a rotatable clothes receptacle, means for treating clothes within the receptacle and a coin-operated timing device, said timing device comprising: a rotatable shaft; means operable upon the insertion of coins of a predetermined denomination to rotate said shaft in a first direction; a motor operable to rotate said shaft in the opposite direction; means coupled to said shaft for controlling the operation of said means for treating clothes; a gear train driven by said motor and connected to said shaft and including a first gear having a plurality of gear sections disposed along its longitudinal axis, each of said sections including different numbers of teeth and all sections having the same mean tooth diameter, a second gear having teeth engageable with the teeth of said first gear, and means for providing relative longitudinal movement between said two gears and releasably and selectively locking said two gears with respect to said longitudinal movement to provide a selected gear ratio therebetween.

12. In a dryer having a coin-operated control mechanism, said mechanism having a motor and means including a driven gear driven by said motor for controlling timing operations of said dryer, an adjustable gear driven by said motor for varying the rate at which said motor drives said means for controlling the timing operations of said dryer, said adjustable gear comprising: an essentially cylindrical member, a first plurality of teeth circumferentially protruding from said member, a second plurality of teeth circumferentially protruding from said member, said second plurality of teeth being longitudinally spaced at a distance from said first plurality of teeth, locking means for locking said member in a position for engagement of one of said first and second pluralities of teeth with said driven gear, whereby the positioning of said gear for engagement with said driven gear determines the rate at which said motor drives said means for controlling timing operations of said dryer.