US 3564186 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
United States Patent Inventors Robert A. Mittelstadt Burnsville; Heinrich F. Tetzlaff, St. Paul, Minn. Appl. No. 757,388 Filed Sept. 4, 1968 Patented Feb. 16, 1971 Assignee Toro Manufacturing Corporation Minneapolis, Minn.
SWITCH CONTROL MECHANISM 15 Claims, 10 Drawing Figs.
US. Cl. 200/172, 200/161 Int. Cl. H0lh 3/02 Field of Search 200/172A, 161 5 6/25 .4
References Cited UNITED STATES PATENTS 8/1939 Winning 200/l6l(X) 9/1958 Konle 56/25.4 12/1959 Houston 200/161 4/1963 Slemmons 56/254 l/l966 West 56/254 Primary ExaminerH. 0. Jones Attorneys- Vernon A. Johnson and Thomas A. Lennon ABSTRACT: A remote control lever for operating the On- Off" switch of the motor of an electric mower. The lever is mounted on the handle and manipulated by the operator while standing behind the handle. The lever travels in parallel offset tracks so that in traveling from the Off to the On position, the lever comes to a full stop at the offset point and must be forcibly moved from one slot to the other in order to reach the On" position.
PATEN TEU FEB] s l97l FIG. 4
8 INVENTORS ROBERT A. M/TTELSTADT Hf/NR/CH F TETZLAFF arw/a fiww ATmR/VEY FIG. 7
SWITCH CONTROL MECHANISM In electric rotary mowers it is desirable to be able to start and stop the motor while standing a safe distance from the housing to prevent the operators feet from coming in contact with the moving cutter blade. It is also desirable for the operator not to be exposed to the discharge opening when starting and stopping the motor, to avoid the possibility of being hit by an object discharged from said opening. 1
It is also desirable to preventrapid repeated movement of the switch between n and Off positions to avoid damaging or burning out the switch.
It is further desirable to prevent accidental starting of the mower by inadvertent actuation of the motor switch.
Therefore, an important object of this invention is to provide a switch control mechanism which will enable the operator to start and stop the motor from a safe location with respect to the housing and discharge opening and, more specifically, from a normal operating position behind the mower handle.
Another object is to providea switch control mechanism which inhibits free movement of the control member between "On and 0E positions to discourage playing with the switch in a manner which might damage same, and which also prevents inadvertent starting of the motor.
Another object is to provide remote switch control mechanism which enables the switch itself to be located close to the motor, thereby minimizing the amount of electric wiring needed, and enabling the switch to be protectively located under the motor shroud.
These and other objects and advantages will more fully appear from the following description made in connection with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views, and in which:
FIG. 1 is a perspective view of an electric mower embodying one preferred form of the switch control mechanism of this invention, with the shroud shown in dotted outline for clarity;
FIG. 2 is an enlarged side elevational detail view of the switch and control mechanism therefore;
FIG. 3 is a plan view of the control lever assembly;
FIG. 4 is an end view of the control lever assembly in the Off" position with a portion of the casing broken away for clarity; 1
FIG. 5 is an end view of the control lever assembly in the On" position with a portion of the casing broken away;
FIG. 6 is a bottom plan view of the switch arm and the e1cments for actuating same, as viewed along the line 6-6 of FIG.
FIG. 7 is a side elevational view of a modified formof switch-actuating mechanism;
FIG. 8 is a bottom plan view of the modification of FIG. 7 as viewed along the line 8-8 thereof;
FIG. 9 is an enlarged detail top view of the control lever; and
FIG. 10 is a top plan view of a modified slot fonnation for. controlling the travel of the control lever.
Referring to the drawings, andinitially to FIG. 1, an electric rotary mower is shown having the-usual cutter blade housing 10, with a side discharge opening 11, ground wheels 12, and steering handle 13.
An electric motor 14 for driving the horizontal cutter blade within the housing is mounted on top of said housing. An On- Olf" switch 15 forthe motor is mounted on a supporting plate 16 in contiguous relation to the motor, and is positioned under the protective shroud 17, said plate 16 being mounted on the motor.
A control panel, or escutcheon plate, 18 is mounted on the upper end of the handle 13, which panel supports a switch control lever 19 positioned so that it is within easy reach of an operator standing in normal operating position behind said handle. The lever 19 is operatively connected to the switch 15 (in a manner described in more detail hereinafter) by means extending between said switch and control lever.
Thus, the motor is started and stopped by manipulation of lever 19 by the operator while standing behind the handle in a position where his feet are not near the housing and where he cannot be hit by objects thrown from the discharge opening.
The manner in which the lever 19 is operatively connected to the switch 15 is best seen in FIG. 2. The switch 15 is mounted on a raised portion 16a of the plate 16, and is secured thereto by means of nut 21, screwed on the externally threaded cylinder 21a which extends downwardly from the switch through the plate, with the operating arm 22 (also known as a bat handle) of the switch extending downwardly through cylinder 21a below the plate 16, wires 15a connecting the switch with the motor, it being understood that arm 22 is movable back and forth vto effect opening and closing of the switch to stop and start the motor. 7
-The flexible casing 20 is fastened to .the underside of a depressed, portion 16b of the supporting plate by means of a clamp 23 which is secured to the plate by fastening screw 24. The portion of the casing under the plate is substantially horizontally oriented and directed towards the switch arm 22.
A Boden wire 25 is enclosed within casing 20 and is freely movable therewithin longitudinally thereof. The forward end of the wire extends beyond the casing and through the switch arm 22 through an opening provided in the lower end of said arm, the wire being freely movable'relative to the arm, and is provided with a pair of switch-actuating stop elements 2627 adapted to operate the switch am 22 (which is located between said stops) in response to movement of the Boden wire, the forward stop 26 being adapted to move the switch arm to the Off position, the rearward stop being adapted to move the switch arm to On position. The stops 2627 are adjustably secured to the Boden-wire by setscrews 26a-2 70,
respectively. Cushioning springs 28-29 are coiled about the Boden wire between said stops and the switch am, said springs also protecting against overtravel of the lever.
The rearward end of the Boden wire is connected to the lever 19 and operable thereby, so that when the lever is pushed to its On" (switch closing) position the wire is pushed forwardly carrying with it rear stop 27 which, at the end of its travel, engages switch 22 and pushes it forwardly to its ,On" position. When the lever 19 is pulled rearwardly from its On" to its Off" (switch opening) position, the Boden wire is simultaneously pulled rearwardly, carrying with it front stop 26 which, at the end of its travel, engages the switch arm 22 and moves it to its 011" position, thus providing the desired safe remote control of the motor switch.
The lever 19 is mounted on the control panel 18 by means of a generally triangularly-shaped casing 30, the upper end portion 30a of which extends above the control panel 18. The lower end of the lever is pivotally mounted on the casing at 31, and the upper end extends through and travels in a slot 32 pro vided in the top face of the casing. The rear end of the sleeve 20 is attached to the casing, and the rear end of the Boden wire extends beyond the sleeve and is attached to the lever 19.
The rear (or Off) portion 32a of the slot is wider than the "forward (or On") portion 32b, so that a shoulder, or stop 33,
vide an upper portion 19a which is offset from the lower por tion 1%. The lever also has a grip, or T handle, at the upper end thereof.
The lever is mounted so that when it is in the wider rear slot portion 32a it is in alignmentwith the stop 33, and naturally assumes that position on the right side of 320, being assisted in this respect by a detent 34 formed on the inner wall of the casing and extending towards and facing the lower portion 19b of the lever when it is in slot portion 32a. 1
Thus, the portion of the slot directly behind the shoulder 33 and in alignment therewith and corresponding to the width of said shoulder represents a recess in which the upper portion 19a of the lever is always located when the lever is in rear slot portion 32a. This same recess represents and provides a straight track or path of travel for the lever which is offset from and parallel to the straight track and path of travel provided by the forward slot portion 32b.
The lower portion 19b of the lever is coplanar with the front slot portion 32b when the lever is in the rear slot portion 32a. To assure that the lever will engage the stop 33 during its forward movement, the lower leg 19b of the lever is provided with a detent 35 which extends laterally towards the casing detent 34 for cooperative engagement therewith. As the lever approaches stop 33, detent 35 engages and rides over detent 34, which forces or biases the lever momentarily to the right to assure its engagement with stop 33, detent 35 clearing detent 34 and being positioned forwardly thereof when the lever is engaged with stop 33. The detents 34-35 also cooperate to force the lever back into the recess portion of slot 32a upon the return travel of the lever from On to OfF position.
In order to move the lever 19 into the offset forward slot portion 32b, the lever must be forcibly bent to the left, with the lever being provided with enough inherent play or resiliency to enable this to be accomplished, and is under tension when in slot portion 32b, which tension biases the lever towards the right, or recessed Off position. It is preferable that a minimum of 4 pounds side force be required at the T handle to move the lever from stop 33 into the forward slot portion 32b.
Thus, when the motor is stopped the lever 19 is in the extreme rearward Off position in the right-hand or recessed part of rear slot portion 32asTo' start the motor the lever 19 is initially pushed forwardly until it reaches stop'33, which is intermediate the motor stopping "Off" and the motor starting On positions. The lever is then forcibly pushed and bent to the left, tensioning the lever and positioning it in slot 32b, whereupon the lever is again pushed forwardly to the extreme forward On" position. I
To stop the motor, the lever 19 is pulled rearwardly from the extreme forward On" position along the slot 32b until it clears shoulder stop 33, whereupon the tension in the lever automatically moves the lever to the right into the right recessed portion of slot 32a, and further rearward travel along the right recessed side of slot 32a brings the lever to the motor stopping Off position.
Thus, if the lever is accidentally bumped or pushed when in the Off position, it will encounter and be stopped by stop shoulder 33 before it reaches motor starting On position, thereby preventing inadvertent starting of the motor.
The intermedia'te'stop shoulder 33 also provides a sufficient time delay between opening and closing of the switch so that the switch will not be damaged or burned out if someone repeatedly moves the lever between On and Off" positions in quick succession.
The stop 33 also minimizes the chances of the motor being started by small children, since they tend to be deterred from further effort when the lever encounters stop 33, or will simply flick the lever back and forth between the stop and the Off position. v
FIGS. 7 and 8 illustrate a modified form of switch-actuating mechanism in which the stops 26-27 are'eliminated,'and the Boden wire is suitably bent or deformed so that the wire itself serves as the means for tripping the switch arm 22. In this version, the extreme forward end of theBoden wire is bent or hooked, as at 25a, so as to engage the switch arm and pull it to the Off" position when the lever 19 is pulled rearwardly to its "Off" position. Rearwardly of the switch arm, a portion of the Boden wire is coiled, as at 25b, which coiled portion serves to engage the switch arm and push it forwardly to its On" position when the lever 19 is pushed forwardly to its On" position. The segment of the Boden wirebetween the portions 25a-25b travels freely in the opening in the switch arm. The coiled portion also serves as a spring which protects against overtravel of the lever in either direction.
FIG. 10 illustrates a modified slot formation designed to accomplish the same safe interrupted lever movement hereinbefore described. In this version, a front "On" slot 36 and a rear "Off" slot are provided, which slots are in parallel staggered offset overlapping relationship, with their inner adjacent ends in lateral communication with each other so that the lever can be shifted laterally from one slot to the other. Thus, slot 36 corresponds to slot 32b, and slot 37 corresponds to the recessed portion of slot 32a. Slot 37 terminates forwardly at stop shoulder 38, and slot 36 terminates rearwardly at stop shoulder 41. Thus, to start the motor, the lever 19 is pushed forwardly from its extreme rear Off position in slot 37 until it encounters stop 38, where its forward movement is arrested. It is then forced laterally to the left into slot 36, and pushed forwardly to the extreme forward On position. To stop the motor, the aforedescribed lever movement is reversed, so that the lever first encounters stop 39, and then is shifted laterally to the right into slot 37, and then continues rearwardly to the Off position.
FIG. 10 also schematically illustrates an additional safety feature which may be incorporated into the switch control mechanism. This additional feature comprises a stop or keeper 39 which is mounted alongside the slot and extends horizontally towards the opening between the slots 36 and 37, so as to be in opposed relationship to the lever 19 when it is positioned at stop 38. When so positioned, it prevents the lever from being shifted into slot 36. The keeper is pivotally mounted to enable it to be swung upwardly to a substantially vertical nonobstructing position, so that the lever can be moved from one slot to the other. The keeper is preferably spring-biased downwardly by any suitable means, such as spring 40, which automatically returns the keeper to horizontal lever obstructing position and holds it there until it is physically lifted. It will, of course, be understood that various changes may be made in the form,'detail, arrangement and proportion of the parts without departing from the scope of this invention.
We claim: 1. In combination:
an electric motor; an On-Off" switch for said motor and operatively connected therewith; said switchhaving a movable switch-actuating element for opening and closing said switch; switch control means remote from said switch and movable between switch opening and switch closing positions; actuating means actuated by said control means extending between said control means and said element and adapted to move said element between switch closing and switch opening position in response to said movement of said control means between said switch closing and switch opening positions; and I means interrupting the movement of said control means between switch opening and switch closing positions.
2. The combination of claim 1, wherein said motor and switch are mounted on a ground traversing implement:
said implement having a steering handle behind which the operator stands when operating said implement; and
said control means mounted on said handle and manipulateble by said.operator while standing in normal operative position behind said handle.
3. The combination of claim 2, wherein said implement is a rotary mower having a cutter blade housing:
said motor mountedon said housing;
wherein saidactuating means includes a wire connected with and longitudinally movable by said control means when it moves between its switch opening and closing positions; and
wire carrying means adapted to engage said element and move same between switch opening and switch closing dinally shiftable in'response to the movement of said control means;
a pair of means carried by said wire adapted to selectively engage said arm and selectively move same to switch opening and switch closing position.
5. The combination of claim 4', wherein said wire is bent to provide said pair of arm-engaging means.
6. The combination of claim 4,;wherein said wire is bent to provide a spring portion. I
7. The combination of claim 4, wherein said wire has bent portions providing said pair of arm-engaging means; at least one of said bent portions also functioning as a spring.
8. The combination of claim 4, wherein said wire extends through an opening in said arm; wherein said means adapted to selectively engage said arm comprise a pair of stop elements carried by said wire and disposed on opposite sides of said arm.
9. in combination:
an electric motor; v I
an On-Off" switch for said motor and operatively connected therewith;
said switch having a movable switch-actuating element for opening and closing said switch; I
switch control means remote from said switch and movable between switch opening and switch closing positions;
actuating means actuated by said control means extending between said control means and said element and adapted to move said element between switch closing and switch opening position in response to said-movement of said control means between said switch closing and switch opening positions;
wherein said control means comprises a pivotally mounted lever swingable between switch closing and switch opening positions;
structure defining slot means in which said lever travels between said positions;
said slot means being offset intermediate said opening and closing positions;
said offset providing a shoulder which engages said lever and stops the movement thereof towards switch closing position; and
said lever being laterally movable to free it from engagement with said shoulder and thereby permit continued movement thereof to switch closing position.
10. The combination of claim 9, wherein said lever, when traveling from switch closing to switch opening position, is biased into alignment with said shoulder after passing same.
11. The combination of claim 10, wherein said lever when in the portion of said slot means between said shoulder and switch closing position is inherently laterally tensioned and biased in the direction of said shoulder and moves of its own volition into alignment with saidshoulder when it passes said shoulder during movement from switch closing to switch opening position.
12. In combination:
an electric motor; I I
an "OnOff" switch for said motor and operatively connected therewith;
said switch having a movable switch-actuating element for opening and closing said switch;
switch control means remote from said switch and movable I adapted to move said element between switch closing and SW1 ch opening position in response to said movement of said control means between said switch closing and switch opening positions; 7
means providing a first straight path'of travel for said control. means from switch opening position to a stop member located between said positions which arrests the movement of said control means towards switch closing position;
means providing a second straight path of travel for said control means from said stop member to switch closing position; 1
said second path being offset from and parallel to said first path and in communication therewith for movement of said control means from said first path to said second path; and I said control means being laterally movable when engaged I with said stop member from said first path to said second path.
13. The combination of claim 12, wherein said lateral movement of said. control means tensions same whereby said control means, when traveling from switch closing to switch opening position, is automatically moved by said tension from said second path to said first path when said control means moves.
past said stop member.
14. The combination of claim 13, wherein said switch includes a depending operating arm movable between'switch closing and switch opening positions:
a wire connected to said control means and longitudinally shiftable in response to the movement of said control means between said positions; and
said operating arm being moved between said positions in response to the longitudinal shifting movement of said wire.
15. In combination:
an electric motor;
an On-Off" switch for said motor and operatively connected therewith;
said switch having a movable switch-actuating element .for
opening and closing said switch;
switch control means remote from said switch and movable between switch opening and switch closing positions;
actuating means actuated by said control means extending between said control means and said element and adapted to move said element between switch closing and switch opening position in response to said movement of said control means between said switch closing and switch opening positions;
movable s'top means interposed in the path of travel of said control means between switch opening and switch closing positions;
said stop means when so interposed preventing said control means from reaching said switch closing position from said switch opening position;
said stop means being movable to a position which frees said control means for continued travel to said switch closing position; and
means biasing said stop means towards said interposed position. 7