US3774127A

US3774127A - Motor timer

Info

Publication number: US3774127A
Application number: US00278282A
Authority: US
Inventors: T Ohashi
Original assignee: Idec Izumi Corp
Current assignee: Idec Izumi Corp
Priority date: 1971-08-09
Filing date: 1972-08-07
Publication date: 1973-11-20
Anticipated expiration: 1990-11-20

Abstract

A motor timer comprising a casing, an electromagnet disposed within the casing, an instantaneous switch and a timing switch disposed on opposite sides of the electromagnet within the casing, an actuating member extending laterally above the electromagnet and operatively connected to a movable core associated with the electromagnet, spring means normally urging the actuating member away from the electromagnet, a timing gear operatively connected to a motor through a reduction gearing and a clutch unit, and a locking lever extending vertically above the timing switch for normally maintaining the timing switch in the locked position. The instantaneous switch can be immediately actuated in response to the energization of the electromagnet, while the timing gear acts to trip the locking lever with predetermined timing while rotation for unlocking the timing switch from its locked position so that the timing switch can be actuated for timing operation.

Description

United States Patent 91 has Nov. 20, 1973 MOTOR TIMER Primary Examiner-Harold Broome [75] Inventor: Toshiro Ohashi, lkeda, Japan Attorney-Donald Slmpso [73] Assignee: Izumi Denki Company Limited,

Osaka, Japan [57] ABSTRACT [22] Filed: 7, 1972 motor timer comprising a casing, an electromagnet disposed within the casing, an instantaneous switch PP N04 278,282 and a timing switch disposed on opposite sides of the electromagnet within the casing, an actuating member [30] Foreign Application Priority Dta extending laterally above the electromagnetand oper- Au 9 l 971 Ja an 46/712153 atlvely connected to a movable core associated with A 1971 J p 46 266 the electromagnet, spring means normally urging the ug. apan /7l actuating member away from the electromagnet, a timing gear operatively connected to a motor through 335/68, 20011308133333; a reduction gearing and a clutch unit, and a locking [58] Field 69 70 71 lever extending vertically above the timing switch for 74 f 6/ normally maintaining the timing switch in the locked position. The instantaneous switch can be immediately actuated in response to the energization of the electro- [56] References Cited magnet, while the timing gear acts to trip the locking UNITED STATES PATENTS lever with predetermined timing while rotation for un- 2,325,860 8/1943 Kizaur 335/72 locking the timing switch from its locked position so HaflStlein 8t 335/74 that the timing switch can be actuated for timing oper- 7 1 Koeh er 335/65 atim 3,665,348 5/1972 Haydon et al. 200/38 3 Claims, 3 Drawing Figures FIGQ I MOTOR TIMER BACKGROUND OF THE INVENTION FIELD OF THE INVENTION This invention relates to motor timers of small overall size and simple construction having a rational arrangement of parts including a timing switch, an instantaneous switch, a clutch, and other components.

' SUMMARY OF THE INVENTION It is a primary object of the present invention to provide an improved motor timer of the kind above described which is simplified in the means for actuating the timing switch and in the construction of the clutch.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a partly vertical sectional, front elevation of an embodiment of the present invention.

FIG. 2 is a side elevation of the motor timer shown in FIG. I, with a casing removed to show the internal structure.

FIG. 3 is an enlarged vertical section of a clutch unit in the motor timer shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, a motor 1 is disposed within a timer casing and the motor shaft In of the motor I is connected to a timing gear 4 through a reduction gearing 2 and a clutch unit 3. The timing gear 4 is provided with a lug 4a adjacent to the outer periphery thereof, and a pointer 4b is rotatable relative to a dial 40. An electromagnet 5 is disposed at the center of the space within the timer casing beneath the motor 1. A movable core 5a is vertically movably disposed in the central opening of the electromagnet 5 and is connected at its upper end. to an intermediate portion of an actuating member 7 by a pivot pin 6. An insantaneous switch 8 is disposed on one side of the electromagnet 5 and a switch actuator 8a extends upward from the switch 8 opposite to one or right-hand end of the actuating member 7 in FIG. I. A timing switch 9 is disposed on the opposite side of the electromagnet 5 in such a manner that the

switches

8 and 9 are symmetrical with respect to the electromagnet 5. A switch actuator 9a having an engaging portion 9b formed at its upper end extends from the switch '9, and the engaging portion 9b is releasably engaged by an engaging portion 11a formed at the lower end of a locking lever 11 pivoted at an intermediate portion thereof toa stationary frame member 10. A depressing rod 12 is pivoted at one end thereof to the upper end of the movable core 5a by the pivot pin 6 together with the actuating member 7. The free end of the depressing rod 12 is suitably vertically spaced from the other or left-hand end of the actuating member 7 and is opposite to the upper end of the actuator 9a of the timing switch 9, as shown in FIG. 1.

A spring 13 is interposed between the left-hand end of the actuating member 7-and the free end of the depressing rod 12 so that normally the depressing rod 12 tends to swing counter-clockwise. However, an abutment 7a extends from a portion of the actuating member 7 and normally engages the lower surface portion of the depressing rod 12 so as to limit the swinging movement of the depressing rod 12in the counterclockwise direction. A plurality of springs 14 are interposed between the actuating member 7 and the electromagnet 5 for normally urging the actuating member 7, hence the movable core 5a upward away from the electromagnet 5. The locking lever 11 is bent at its upper free end portion in a .horizontal direction as shown so that the free end of the locking lever 1] lies in the path of the lug 4a during rotation of the timing gear 4. Thus, in response tothe rotation of the timing gear 4, the lug 4a engages and drives the upper free end of the locking lever 11 so as to swing the locking lever 11 clockwise in FIG. 2 around the point at which the lever 11 is pivoted to the frame member 10. A spring 15 is anchored at one end thereof to a suitable portion of the locking lever 11 beneath the point pivoted to .the

frame member 10 and at the other end thereof to a suitable portion of the frame member 10. Thus, the locking lever 11 is normally urged counter-clockwise in FIG. 2 so that the engaging portion 11a at the lower end of the locking lever l 1 can be normally engaged by the engaging portion 9b at the upper end of the actuator9a of the timing switch 9.

Referring to FIG. 3 showing the structure of the clutch unit 3 in enlarged section, a first transmission gear 81 is in meshing engagement with one of the gears in the reduction gearing 2, and a second transmission gear 82 is in meshing engagement with the timing gear 4. The first transmission gear 81 having a central axial opening 81a is rotatably supported at is lower extension on a base 60 to which the motor I is mounted. A pair of central shafts. 82a and 82b extend in opposite directions from the second transmission gear 82. The upper shaft 82a extends upward through an opening in a stationary frame member to project slightly from this opening, while the lower shaft 82b extends through the central opening 810 in the first transmission gear 81 and through an opening in the base 60 to abut at its lower end with a portion of the actuating member 7. The first and second transmission gears -81 and-82 are provided with respective clutch portions 81b and 82c opposite to each other so that the rotation of the first transmission gear 81 can be transmitted to the second transmission gear 82 when these clutch portions 81b and 82c are brought into frictional engagement. Due to the fact that the actuating member 7 is normally urged upward away from the electromagnet 5 by the force of the springs 14, the lower shaft 82b of the second transmission gear 82 is also urged upward by the actuating member 7 so that the second transmission gear 82 is normally urged upward to be disengagedfrom the first transmission gear 81. The upper end of the upper shaft 820 of the second transmission gear 82 projecting slightly fromthe opening in the frame member I30 is engaged by a leaf spring 16 fixed to the upper surface of the frame member 130 so that the upper shaft 82a of the second transmission gear 82 is normally urged downward by the leaf spring 16 whose force is smaller than the total force of the springs 14.

In operation, when the electromagnet 5 is energized to attract the movable core 5a downward against the force of the springs 14, the second transmision gear 82 having been urged upward by the force of the springs 14 through the actuating member 7 is now urged downward by the force of the lead spring 16, with the result that the clutch portion 82c of the second transmission gear 82 is brought into frictional engagement with the clutch portion 81b of the first transmission gear 81 and the rotation of the motor 1 is transmitted through the first transmission gear 81 to the second transmission gear 82 to cause rotation of the timing gear 4. When the electromagnet is subsequently de-energized, the movable core 5a is urged upward by the force of the springs 14 again and then the second transmission gear 82 is urged upward away from the first transmission gear 81 to be disengaged from the latter.

The clutch unit in the motor timer according to the present invention is advantageous in that means such as crank means used commonly in prior art devices need not be provided by virtue of the fact that the second transmission gear 82 is arranged to move in the same direction as that of the movable core 5a for carrying out the clutch action. In other words, the clutch unit can operate with a smaller number of parts than heretofore due to the fact that the motion of the movable core 50 can be directly transmitted to the second transmission gear 82.

The present invention is further featured by the fact that the engaging portion 9b at the upper end of the actuator 9a of the timing switch 9 is normally engaged by the engaging portion 110 at the lower end of the locking lever 11 so that the timing switch 9 may not be actuated until the engaging portion 9b is disengaged from the engaging portion lla. More precisely, in response to the energization of the electromagnet 5, the movable core 50 is attracted to move downward against the force of the springs 14, and at the same time, the actuating member 7 connected to the movable core 5a is also urged downward. Although, in this case, the instantaneous switch 8 is actuated immediately due to the fact that the actuator 8a disposed opposite to the righthand end of the actuating member 7 is urged downward by the member 7, the actuator 9a of the timing switch 9 would not be urged downward by the depressing rod 12 even with the downward movement of the actuating member 7 due to the fact that the engaging portion 11a at the lower end of the locking lever 11 is still in engagement with the engaging portion 9b at the upper end of the actuator 9a and prevents downward movement of the actuator 9a, resulting merely in compression of the spring 13 interposed between the actuating member 7 and the depressing rod 12. In the meantime, the downward movement of the actuating member 7 causes transmission of the rotation of the motor 1 to the timing gear 4 through the reduction gearing 2 and clutch unit 3 thereby causing rotation of the timing gear 4. As the timing gear 4 is rotated, the lug 4a provided on the timing gear 4 engages and drives the upper free end of the locking lever 11 to cause swinging movement of the lever 11 around the point pivoted to the frame member 10. As a result, the engaging portion lla at the lower end of the lever 11 is disengaged from the engaging portion 9b at the upper end of the actuator 9a of the timing switch 9, and the actuator 9a is now freed from the locked position. The spring 13 compressed between the actuating member 7 and the depressing rod 12 is now free to extend and forces the actuator 9a downward to actuate the timing switch 9 for timing operation. In response to the de-energization of the electromagnet 5, the movable core 5a, actuating member 7 and depressing rod 12 are urged upwardly by the force of the springs 14, and the engaging portion 9b of the actuator 9a of the timing switch 9 is engaged by the engaging portion 11a of the lever 11 again as will be readily apparent to those skilled in the art.

It will be understood from the foregoing description that the present invention provides a motor timer of very simple construction consisting of a small number of parts since mere provision of the lever ll on the frame member 10 can easily lock and unlock the timing switch 9.

I claim:

1. A motor timer comprising a casing, an electromagnet disposed at a lower central position within said casing, an instantaneous switch and a timing switch disposed on opposite sides of said electromagnet within said casing, an actuating member extending laterally above said electromagnet and operatively connected to a movable core associated with said electromagnet said instantaneous switch being adapted to be immediately actuated by said actuating member in reponse to the energization of said electromagnet, spring means normally urging said actuating member away from said electromagnet, an electric motor disposed at an upper position within said casing and cooperatively associated with said electromagnet, a timing gear adapted to be operatively connected to said motor through a reduction gearing and a clutch unit, said clutch unit being adapted to be immediately actuated by said actuatingmember in response to the energization of said electromagnet to operatively connect said timing gear to said motor through said reduction gearing to thereby rotate said timing gear, and a locking lever extending vertically above said timing switch within said casing for normally maintaining said timing switch in the locked position, where-by said locking lever being actuated by said timing gear after a predetermined lapse of time from the actuation of said timing gear to unlock said timing switch from its locked position so that said timing switch is actuated for timing operation.

2. A motor timer as claimed in claim 1, wherein said actuating member operatively connected to said mov-v able core is disposed so that one end thereof is opposite to an actuator of said instantaneous switch and the other end thereof is opposite to an actuator of said timing switch, and said locking lever is pivotally supported at a substantially intermediate portion thereof in a manner so that one end of said locking lever normally engages with said actuator of said timing switch so as to maintain said timing switch in the locked position and the otherend of said locking lever is disposed to be urged in one direction with the rotation of said timing gear after said predetermined lapse of time from the actuation of said timing gear to release said actuator of said timing switch from the engagement with said one end of said locking lever to thereby enable said timing switch to become in the unlock position.

3. A motor timer as claimed in claim 1, said clutch unit including a first transmission gear having a central axis opening and a clutch portion, said first transmission gear being in meshing engagement with one of the gears in said reduction gearing driven by said motor, a second transmission gear having a clutch portion opposite to the clutch portion of said first transmission gear and a first and a second shaft extending in opposite directions therefrom, said second transmision gear being in meshing engagement with said timing gear, said first shaft extending through said opening in said first transmissiongear to abut atthe lower end thereof with a portion of said actuating member normally urged away from said electromagnet by said spring means, and a spring engaging said second shaft for normally urging said second transmission gear toward said first transmission gear with a force smaller than that of said spring means, whereby said clutch portions of said first and second transmission gears can be brought into frictional engagement when said movable core is attracted by said electromagnet.

i Il

Claims

1. A motor timer comprising a casing, an electromagnet disposed at a lower central position within said casing, an instantaneous switch and a timing switch disposed on opposite sides of said electromagnet within said casing, an actuating member extending laterally above said electromagnet and operatively connected to a movable core associated with said electromagnet said instantaneous switch being adapted to be immediately actuated by said actuating member in reponse to the energization of said electromagnet, spring means normally urging said actuating member away from said electromagnet, an electric motor disposed at an upper position within said casing and cooperatively associated with said electromagnet, a timing gear adapted to be operatively connected to said motor through a reduction gearing and a clutch unit, said clutch unit being adapted to be immediately actuated by said actuating member in response to the energization of said electromagnet to operatively connect said timing gear to said motor through said reduction gearing to thereby rotate said timing gear, and a locking lever extending vertically above said timing switch within said casing for normally maintaining said timing switch in the locked position, where-by said locking lever being actuated by said timing gear after a predetermined lapse of time from the actuation of said timing gear to unlock said timing switch from its locked position so that said timing switch is actuated for timing operation.

2. A motor timer as claimed in claim 1, wherein said actuating member operatively connected to said movable core is disposed so that one end thereof is opposite to an actuator of said instantaneous switch and the other end thereof is opposite to an actuator of said timing switch, and said locking lever is pivotally supported at a substantially intermediate portion thereof in a manner so that one end of said locking lever normally engages with said actuator of said timing switch so as to maintain said timing switch in the locked position and the other end of said locking lever is disposed to be urged in one direction with the rotation of said timing gear after said predetermined lapse of time from the actuation of said timing gear to release said actuator of said timing switch from the engagement with said one end of said locking lever to thereby enable said timing switch to become in the unlock position.

3. A motor timer as claimed in claim 1, said clutch unit including a first transmission gear having a central axis opening and a clutch portion, said first transmission gear being in meshing engagement with one of the gears in said reduction gearing driven by said motor, a second transmission gear having a clutch portion opposite to the clutch portion of said first transmission gear and a first and a second shaft extending in opposite directions therefrom, said second transmision gear being in meshing engagement with said timing gear, said first shaft extending through said opening in said first transmission gear to abut at the lower end thereof with a portion of said actuating member normally urged away from said electromagnet by said spring means, and a spring engaging said second shaft for normally urging said second transmission gear toward said first transmission gear with a force smaller than that of said spring means, whereby said clutch portions of said first and second transmission gears can be brought into frictional engagement when said movable core is attracted by said electromagnet.