US 3930131 A
A timer for electrical applicances having a simple construction with very few parts and in which the time settings for minutes and hours, or any division thereof, are independently entered through time setting discs, digitally displayed through a common window and internally stored. In the timer a single lever engages two grooved discs, each disc being associated with the time setting discs. A planetary gear mechanism links the time setting discs and the associated groove discs. The lever, after the elapse of the set time activates a switch by engagement of lever pins with the grooves of the discs thereby tripping a latched switch actuator.
Claims available in
Description (OCR text may contain errors)
United States Patent 1 Nishina Dec. 30, 1975  Inventor:
 Assignee: Tamura Electric Works, Ltd.,
Tokyo, Japan 22 Filed: Feb. 14, 1974 21 Appl. No.: 442,619
Rintaro Nishina, Yonezawa, Japan  US. Cl. 200/35 R; 58/21.13; 58/395;
' 200/38 R; 200/39 R  Int. Cl. H01I-I 43/00; G04F 3/02  Field of Search 74/35, 3.54; 58/21.l3,
58/395; 200/35 R, 38 R, 38 A, 38 F, 38 FA, 38 PB, 39 R, 39 'A  References Cited UNITED STATES PATENTS 3,124,668 3/1964 Zagorski et a1. 200/39 R X 3,610,753 10/1971 Neubauer 200/38 FA X FOREIGN PATENTS OR APPLICATIONS 520,618 4/1940 United Kingdom 200/39 R 296,693 2/1917 Germany 200/39 R Primary Examiner.lames R. Scott Attorney, Agent, or FirmRoland Plottel 57 I ABSTRACT A timer for electrical applicances having a simple construction with very few parts and in which the time settings for minutes and hours, or any division thereof, are independently entered through time setting discs, digitally displayed through a common window and internally stored. 1n the timer a single lever engages two grooved discs, each disc being associated with the time setting discs. A planetary gear mechanism links the time setting discs and the associated groove discs. The lever, after the elapse of the set'time activates a switch by engagement of lever pins with the grooves of the discs thereby tripping a latched switch actuator.
9 Claims, 6 Drawing Figures REDUCTION GEAR:
U.S. Patent Dec .30,1975 Sheetl0f3 3,930,131
US. Patent Dec. 30, 1975 Sheet 2 of3 3,930,131
U.S. Patent Dec. 30, 1975 Sheet 3 Of3 3,930,131
WQQWQ 20k $3 0 TIMER FOR CONTROLLING THE OPERATION OF ELECTRICAL DEVICES This invention relates to a timer having simple construction, that can be readily set to the time at which it operates and can operate accurately.
Various types of timers are now being used for electric appliances and many other applications. However, prior art timers are complicated in construction and expensive because they use complicated gear mechanisms. Moreover, it has been impossible to set the operating time during a certain period between the closed and opened states of the switch.
According to this invention, there is provided a timer comprising a first shaft rotated intermittently at a relatively high speed, a second shaft rotated intermittently at a relatively low speed, first and second discs mounted on the first and second shafts respectively, each of the discs being provided with a groove on its periphery, a pivotally mounted lever including a pair of pins urged to respectively engage the peripheries of the first and second discs, a switch arranged to be operated by the lever when the pair of pins engage the grooves, a pair of time setting discs, and a pair of planet gear mechanisms respectively provided between the time setting discs and the grooved discs.
The invention can be more fully understood from the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a diagrammatic representation of one example of the timer embodying the invention;
FIG. 2 shows an operated condition of the mechanism shown in FIG. 1;
FIG. 3 shows a perspective view, partly broken away, of a time setting mechanism shown in FIGS. 1 and 2;
FIG. 4 is a plan view showing the relationship between a grooved disc and a pin cooperating therewith, and
FIG. 5 shows a plan view, partly broken away, of the time setting discs.
F IG. 6 is a perspective partially exploded view showing the interrelation of the various parts of the mechanism as shown in FIGS. l'through 5.
Referring now to the accompanying drawing, a preferred embodiment shown therein comprises a shaft 1 which is rotated intermittently at a high speed, for example, one revolution per minutes, by suitable driving means such as a synchronous motor and generally termed a ten minutes shaft, and a shaft 2 which is rotatedintermittently at a low speed, for example one revolution per hour, and generally termed a hour shaft. Grooved discs 3 and 4 are mounted on 10 minutes shaft 1 and hour shaft 2, respectively.
There is also provided a letter T shaped lever 5 pivotally mounted on pin 6. At the ends of respective legs of the T shaped lever 5 are mounted pins 7a, 7b and 7c; pins 7a and 7b being urged against the peripheries of the grooved discs 3 and 4, respectively. Lever 5 is biased in the direction of arrow 9 by means of a spring 8 so as to rotate in the clockwise direction about pin 6.
A cam lever 10 for operating a switch consisting of leaf springs 15a and 15b which carrycooperating contacts is pivotally mounted on apin 11 and is biased in the direction of arrow 13 by means of a spring 12.
As shown in FIG. 3, the time setting mechanism comprises a time setting disc 16 mounted on the upper portion of the 10 minutes shaft 1. A stub shaft 17 is secured to the lower surface of disc 16 to support gears 18 and 19 which cooperate respectively with gears 21 and 20 mounted on shaft 1. It is to be understood that similar time setting mechanism is also provided for the hour shaft 2.
The gear 21 is fastened to shaft 1. When the time setting disc 16 is rotated, gears 18 and 19 are caused to revolve about gear 21 as planet gears. Since gear 19 meshes gear 20 which is fastened to grooved disc 3, when disc 16 is rotated, grooved disc 3 is also rotated about shaft 1, thereby varying the relative position between pin 7a and groove 22 of disc 3. In the condition shown in FIG. 2, pins 7a and 7b are received in grooves 22 and 23 respectively of discs 3 and 4.
Under these conditions, the force of spring 12 overcomes the force of spring 8 whereby the cam lever 10 is disengaged from pin 7c and brought to a position shown in FIG. 2. At this position, a projection 10a at the lower end of cam lever 10 engages leaf spring 15a to close switch contacts 150.
FIG. 4 shows a condition wherein pin 7a is at the midpoint of the range of movement of grooved disc 3. More particularly, as shaft 1 is rotated from a position of minutes, disc 3 is moved through an arc AOA' through gears 21, 18, 19 and 20. During this movement, pin once drops in the groove 22 at position B but is immediately moved out of the groove to position B by the action of spring 8. The grooved disc 4 and pin 7b undergo an identical relative motion.
FIG. 5 shows a set time display device comprising a frame 24 having a window 25 at the center and the ten minutes shaft 1 and hour shaft 2 extend through the frame 24 on both sides of window 25. Shafts 1 and 2 are provided with knobs 26 and 26a respectively. Set discs 16 and 1611 are provided for shafts l and 2 respectively. These discs are marked with digits representing minutes and hours respectively, these digits can be seen through window 25. Accordingly it is possible to set any desired time while viewing these digits.
In this example, shaft 1 is driven intermittently to rotate 60 each 10 minutes, thus completing one revolution per hour, whereas shaft 2 is intermittently rotated so as to make one complete revolution per 24 hours. It will be clear that shafts 1 and 2 may be rotated at any desired rates, and that these shaft can be driven by any well known driving mechanism.
The novel timer has following advantages.
1. It is possible to independently set the time setting discs for 10 minutes order and hour order and to digitally display the set time. Accordingly, by the suitable selection of the size of the setting discs and the digits marked thereon it is possible to display any time with any desired size.
2. As a planet gear mechanism is used to set a selected time, by selecting a suitable gear ratio, it is possible to accurately set the desired time with a unit of 12 hours or 24 hours.
3. As a single lever 5 is used in common for two discs 3 and 4 to acuate a single' switch it is possible to simplify the construction of the timer.
4. In the prior art timer, although there is a range in which it is impossible to set the time between the ON and OFF states of the switch, according to this invention, this defect can be obviated because the novel timer utilizes a planet gear mechanism, grooved discs and a common lever. While the invention has been shown and described in terms of a preferred embodiment thereof it will be clear 3 that many changes and modifications can be made without departing from the true scope of the invention as defined in the appended claims.
1. A timer comprising a. first shaft means for intermittent rotation at a relatively high speed;
b. second shaft means for intermittent rotation at a relatively low speed;
0. first and second grooved disc means mounted on said first and second shaft means respectively for free rotation thereon, each of said disc means being provided with a groove on its periphery;
d. pivotally mounted lever means including a lever and a pair of pins thereon for respectively engaging with said pins the peripheries of said first and second disc means; I
e. switch arranged to be operated by said lever when said pair of pins engage said grooves; v
f. first and second time setting disc means associated respectively with said first and second shaft means, for beingrotatably displaced by an external force,
said displacement being proportional to atimesetting;
g. first and second planetary gear mechanism means, i
the first of which is connected between said first grooved disc means and said first time setting disc means, and the other is connected between said second grooved disc means and said second time setting disc means; and said first and second planetary gear mechanismmeans being drivably connected respectively to said first and second shaft means for rotatably displacing said grooved disc means proportional to the displacement of the corresponding time setting disc means, and for v rotatably turning in the opposite sense said grooved disc means and said time setting disc means driven by rotation of its .corresponding shaft means;
whereby for a timer in an initial position with the H pins positioned at the grooves ofthe grooved disc vvmeans, has a desired time setting rotatably entered on the time setting disc means which displace said grooved disc means proportionally,
. after which said shaft means. drive said discs through said planetary gear means until said grooves are brought to engagement with said pins .thus activating said switch.
2. The timer according to claim 1 which further comprises a third pin carried by said lever means, a pivotally mounted cam lever disposed between said lever means and said switch and a spring normally urging said cam lever to engage said third pin to hold said switch in the open condition.
3. The timer according to claim 1 wherein one of said time setting disc means is marked with digits displaying minutes and the other with digits displaying hours.
4. The timer according to claim 1 wherein each of said time setting disc means is loosely mounted on its associated shaft means, and each of said planetary gear mechanism means comprises a first gear secured to its shaft'means, a second gear coaxial with said first gear and secured to its grooved disc means mounted on said shaft means, a third gear meshing said first gear, a fourth gear coaxial with said third gear and meshing .4 said second gear and a stub shaft supporting said third and fourth gears'and secured to the lower surface of its time setting disc means.
5. The timer according to claim 1 wherein said pair of time setting dis'c means are rotatably supported by a frame having a window for displaying digits marked on the peripheries of said time setting discs.
6.'The timer according to claim 1 wherein said lever means is in the form of a letter T and said pins are respectively mounted on each end of the legs of the T.
7. A timer according to claim 1 wherein said lever means includes first springr'neans connected to said lever for normally bearing said lever pins out of engagement with said peripheries of said groove disc means;
pivotally and resiliently mounted cam lever means between said lever and said switch for operating said switch when in a first normal position, for biasing said lever pins into engagement with said peripheries of said grooved disc means when in a second set position, and for movement from said lever set position to said normal position when said lever pins on said peripheries move into said grooves thereinj 8. A timer comprising first and second shafts for rotation at different speeds;
first and second discs freely mounted on said first and second shafts respectively, and each having a groove on its periphery;
a pivotally. mounted lever having a pair of pins thereon for respective engagement with the peripheries of said first and second discs;
a switch positioned proximate to said lever and adapted to be operated by said lever when it pivots due to said pair of pins engaging said grooves;
first and second time setting discs rotatably mounted on said first and second shafts respectively; and v first and second planetary gear mechanism con- 7 nected to the corresponding first and second shafts grooved discs and time setting discs, each mechanisrn including at least one gear fixedly connected to its corresponding shaft, another gear drivably connected to its corresponding time setting-disc, and a third gear drivably connected to its corresponding grooved disc; 1
whereby, displacement of the time setting discs causes rotation of its corresponding grooved disc through the planetary gear mechanismrand rotation of the shafts causes a corresponding rotation but in the opposite sense of the grooved discs and I the time setting discs. v I
9. A timer according to claim 8 wherein said time setting discs are coaxial with their corresponding shaft and freely mounted thereon;'said third gear in said planetary gear assembly is also coaxial with and freely mounted on its corresponding shaft and fixedly attached to said grooved disc, said other gear meshes with said one gear, and is mounted. ,on a spur shaft connected to aface of said time setting disc but displaced from the axis thereof, and there is further provided a fourth gear coaxial with said other gear and in matingengagement with said third gear.