US3007148A

US3007148A - Timer

Info

Publication number: US3007148A
Application number: US818463A
Authority: US
Inventors: John W Morgan
Original assignee: Controls Company of America
Current assignee: Controls Company of America
Priority date: 1959-06-05
Filing date: 1959-06-05
Publication date: 1961-10-31
Anticipated expiration: 1978-10-31

Description

Oct 1, 1961 .1. w. MORGAN 3,007,148

TIMER Filed June 5, L959 2 SheetsSheet 1 INVENTOR, Jorm W. MORGAN 7 ATTORNEY Oct. 1961 J. w. MORGAN 3,007,148

TIMER Filed June 5, 1959 2 Sheets-Sheet 2 Basm TIME CYCLE.

IMPULSE c 5 \5 2 0 25 3 0 3 5 4 0 4 5 5 0 |:ll:lllll||illll lllllllll:glllllllflll[:HIIHLIIHII as P s i g Fue. 8 3 INVENTOR.

28L fmER F\G. 9 Jon-m W. MoRc-mN 30 BY )r I? 26 United States Patent TIME This invention relates to timers and means for accurately positioning the timer at a desired starting point.

With the variations in fabrics, soil condition, etc., the washing machine manufacturers have been compelled to provide a variety of programs for the timer on a machine. Some fabric washing characteristics dictate an entirely dilferent set of operating sequences requiring basic cycles of operation while other fabric washing characterlstics are similar in some respects to the basic fabrics but require only a portion of the sequences provided in the basic cycles. Since a timer has basically 3 60 degrees in which it can operate without repeating, it has become necessary to crowd an ever increasing number of programs into the 360 degrees of rotation available. In order to carry out the program while maintalmng a reasonable stepping action compatible with economic manufacture, the spacing between adjacent programs has been steadily decreased as the number of programs has increased. This has now resulted in a requirement that the timer be accurately positioned generally within three degrees or less to insure starting at the right point. This requirement is virtually beyond the ability of the user without some form of aid in locating the desired starting oint. p The primary object of this invention is to provide an indicator for accurately locating starting points on a timer.

Other objects and advantages will .be pointed out in or be apparent from the specification and claims, as will obvious modifications of the single embodiment shown in the drawings in which:

FIGURE 1 is a plan view in section of a drum type timer.

FIGURE 2 shows a section of the washers flash plate with the pointer for the timer.

FIGURE 3 is taken on line 3-3 of FIGURE 1 showin the drive mechanism for the timer.

FIGURE 4 is an elevation of the timer showing the line switch.

FIGURE 5 is taken on line 5--5 of FIGURE 4 showing the line switch cam and the timer cam.

FIGURE 6 is a schematic showing of the double line and starter switch circuit.

FIGURE 7 is a schematic showing the light indicator circuit with the timing cam out of phase.

FIGURE 8 shows generally a basic time cycle with starting points indicated in half lines and stopping points in double lines.

FIGURE 9 is a schematic of the circuit arrangements for the indicator light.

The invention generally relates to a timer of the type having a synchronous motor 10 that drives a cam drum 12 through a ratchet and pawl arrangement 14. A shaft 18 coaxial with the camdrum has a switch actuating disc 20 mounted adjacent the cam and a bank knob 16 mounted on the outer end. Pushing the shaft inward will cause the disc to actuate line switch 22 to start the timer. To set the timer, the pointer is pulled outward to open the line switch and close light switch 28. The pointer is then rotated turning the drum to the desired starting point.

The starting point indicator shown in the drawings comprises a light 24 mounted at any convenient point on the appliance. It will be obvious that any indicating means such as a bell, buzzer or chime could be used in place of the light. The circuit 26 for the light has two

switches

28 and 3 0 connected in series with the light thus requiring both switches to be closed before the light is illuminated. The first switch 28 is actuated on the outward movement of the disc 20 which movement also opens the line switch. The second switch 30 is actuated by a cam 34 mounted to rotate with the drum and provided with a number of notches '36 corresponding to the starting points on the timer. The pointer cooperates with fixed indicia 32 on the appliance.

If the pointer has been properly aligned with a program starting point camfollower 38 on switch 30 will drop into one of the notches '36 closing the switch and illuminating the light (FIGURE 6). If the pointer is then pushed inward switch 28 will be opened breaking the light circuit and the line switch will be closed starting the timer. The actuation of the light switch in conjunction with the line switch is not essential to the operation of the system but it eliminates the possibility of the light indicator being illuminated each time cam follower 33 bottoms in one of the notches 36 in cam 34.

The notches 36 are cut in the cam so that they bridge only one step, 6 or 7.2 degrees, of a complete revolution. The switch 30 will be closed only when the cam follower 38 bottoms in the notch (FIGURE 7). Since the notch has a cam surface at one side, only about three degrees of the notch will be available to close the switch. With this arrangement a greater degree of accuracy can be obtained to provide an' exact visual indication of a program starting point.

In FIGURE 8 a time cycle is shown having fifty (50) steps, 7.2 degree intervals, for one complete revolution of the timer. The time cycle is divided in five basic programs ending at

steps

14, 25, 37, 4-2 and 50. Starting points are indicated at steps .5, 2.5, -14.5, 25.5, 33.5, 37.5 and 42.5. This cycle thus provides seven programs in one revolution of the timer.

The ratchet and pawl drive consists of a bell crank 42 pivoted on pin 44 and having a cam follower 46 on one arm of the crank biased by spring 48 into engagement with a motor driven cam 12 having a slow rise rapid drop cam surface. A pawl 52 is pivoted on pin 54 mounted on the other arm of the crank and is biased into engagement with ratchet wheel 56 by spring 58. The motor driven cam is rotated at a constant speed by motor 10 so that the bell crank reciprocates on the pivtot advancing the drum in a step by step manner. Reverse rotation of the drum is prevented by pawl 60 biased to engage the ratchet'wheel by spring 62. With this type of drive, the timer can be backed up within the limits of the teeth on the ratchet wheel so that cam follower 33 botoms in the notch thereby assuring that the timer is at the starting point of the selected program cycle.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. A starting point indicator for a timer comprising a shaft, a pointer on the shaft cooperating with a fixed indicia, a light, a circuit for the light and including a switch, means rotatable with the shaft for actuating the switch, said rotatable means having actuating points corresponding to the fixed indicia, a second switch in the circuit, and means moveable axially with the shaft for actuating the second switch, said light being lit when both of the switches have been actuated.

responding to the fixed indicia, and means responsive to the points on'the rotating means indicating when the rotating means is aligned with the starting point indicated by the pointer on the fixed indic'ia.

3. A device according to claim 2 wherein the indicating means includes a light.

4. A device according to claim 2 including a line switch for the timer, means axially moveable with respect to the shaft for engaging the line switch, and said responsive means responding only when the line switch is closed.

5. A device according to claim 4 wherein the responsive means is a light.

6. A starting point indicator for a timer comprising a shaft, a cam bank rotatable with the shaft, fixed indicia, a pointer on the shaft cooperating with the fixed indicia, one of the cams in the cam bank having cam portions corresponding to the fixedv iudicia, and switch means actuated by the cam portions giving indications of start points for the timer corresponding to the start points indicated by the pointer on the fixed indicia.

7. A starting point indicator for a timer comprising a shaft, a cam bank rotatable with the shaft, said shaft being moveable axially with respect to the cam bank, fixed indicia a. pointer on the shaft cooperating with the fixed indicia, circuit means for indicating a starting point having a first and a second switch, means axially moveable with respect to the shaft actuating the first switch, and means on the cam bank for actuating the second switch, said circuit indicating means responding only when both switches have been actuated.

8. An indicator according to claim 7 wherein the shaft actuating means starts the timer on axial movement of the shaft if the second switch has been actuated by the means on the cam bank.

References Cited in the file of this patent UNITED STATES PATENTS