US3590564A

US3590564A - Safety device for mowers

Info

Publication number: US3590564A
Application number: US790188A
Authority: US
Inventors: Herbert B Clifford
Original assignee: POLORON PRODUCTS OF INDIANA
Current assignee: POLORON PRODUCTS OF INDIANA
Priority date: 1968-12-04
Filing date: 1968-12-04
Publication date: 1971-07-06
Anticipated expiration: 1988-07-06

Abstract

A safety device for mowers and particularly riding mowers which requires manual actuation of a mechanism to enable engagement of clutching means between the rotary cutting blades and the engine or other power source and wherein release of the manually operated means will automatically effect disengagement of the clutch.

Description

United States Patent Herbert B. Cliflord Miehlgan City. Ind.

Dec. 4, I968.

July 6, I 971 Poloron Products of Indiana, Inc. Michigan City, Ind.

Inventor Appl No. Filed Patented Assignee SAFETY DEVICE FOR MOWERS 7 Claims, 6 Drawing Figs.

US. Cl 56/ 10.2, 56/ 13.7

Int. Cl. A0ld 35/26 Field ofSearch 180/101;

56/DIG. 15; 86/25.4

[56] References Cited UNITED STATES PATENTS 2.256338 9/1961 Brown 180/101 3229,452 1/1966 Hasenbank 180/101 V Primary Examiner-Robert Peshock Attorney-Eugene E. Geoffrey, Jr.

ABSTRACT: A safety device for mowers and particularly riding mowers which requires manual actuation of a mechanism )4 to enable engagement of clutching means between the rotary cutting blades and the engine or other power source and wherein release of the manually operated means will automatically effect disengagement of the clutch.

PATENTEUJL-L em 3,590,564

SHEET 1 BF 4 ATTORN Y PATENTED JUL 6 l9?! SHEET 2 OF 4 PATENTEU JUL 6 IEWi ATTORNEY SAFETY IDEVIICIE FOR I /IUWIEIlllS This invention relates to safety devices for mowers and more specifically to a novel and improved automatic safety device for use on riding mowers to automatically disengage the cutting blades from the engine should the operator for any reason leave the mower or be accidentally thrown therefrom.

Riding mowers or tractors are customarily provided with high speed rotary blades disposed within a housing supported between the front and rear wheels of the mower or tractor. The blades usually rotate at a speed of the order of the engine speed which is generally in the range of 3,000 to 3,6000 revolutions per minute. It is well recognized that cutting blades operating at these high speeds are extremely dangerous should one accidentally come in contact with them. For this reason the blades are recessed within a heavy metal housing and all precautions are taken to prevent possible injury to the operating personnel. The instant invention affords additional means to insure the safety of operating personnel by providing a novel and improved arrangement and organization of elements which automatically disengages the rotary blades should the operator release the manually operated safety mechanism which must be maintained in a selected position in order for the blade clutching means to be maintained in the engaged position.

A still further object of the invention resides in a novel and improved safety device which must be maintained in a selected position by an operator in order to permit engagement of the blade clutching means for the mowing operation.

A still further object of the invention resides in the provision of a novel and improved safety device for riding mowers wherein the operator must be in position on the mower in order to permit transmission of power to the cutting blades.

The above and other objects of the invention will become more apparent from the following description and accompanying drawings forming part of this application.

In the Drawings:

FIG. II is a side elevational view in partial section of a riding mower with the safety device in accordance with the invention. I

FIG. 2 is a cross-sectional view of FIG. I taken along the line 2-2 thereof;

FIG. 3 is an exploded perspective view of the safety'dcvice in accordance with the invention;

FIG. 41 is a side elevational view of a fragmentary portion of FIG. 1 with the safety device in position to permit engagement of the clutch;

FIG. is a cross-sectional view of FIG. i taken along the line 5-5 thereof with the clutch in the disengaged position; and

FIG. 6 is a view similar to FIG. 5 with the clutch in the engaged position.

While the safety device now to be described is particularly useful with riding mowers or tractors, it will become evident as the description proceeds that the device is equally useful on all types of rotary mowers involving high speed rotary elements for cutting grass and other similar purposes.

Referring to the drawings, the mower in the illustrated embodiment of the invention is provided with a horizontal frame 10 having front and rear wheels Ill and 12, respectively, which are secured to and carry the frame 10. Conventional means are provided for steering the front wheels 11 and for driving the rear wheels 12 from a gasoline engine or other suitable power source 13. While any suitable power transmission mechanism may be utilized for driving the rear wheels 12], in the instant embodiment of the invention, the engine shaft 14 is provided with a V-belt pulley l5 engaging the driving belt 16. The belt 16 engages a second V-belt pulley 117 secured to a shaft 18 extending downwardly from a suitable power transmission mechanism contained within the mower housing generally denoted by the numeral 119. A chain 20 is coupled with the power transmission mechanism and engages a sprocket 21 coupled through a suitable differential to the rear wheel axle 22, the latter being carried by a pair of downwardly extending brackets 23 secured to the frame 10.

The rotary cutter assembly is generally denoted by the numeral 2d and includes a housing 25 having a top wall 26 and a peripheral sidewall 27. The depending side as viewed in FIG. I has an opening 20 through which the cut grass is discharged as a result of the rotation of the blades.

The blades within the housing are each denoted by the numeral 29, are pivotally supported by the top wall 2.6 of the housing 25 and are driven by pulleys 30. The rear portion of the housing 25 is provided with a shaft 3i pivotally supported on the top wall 295 of the housing 25 and carries a pair of V- belt pulleys and 33. The pulleys 30 are driven by the pulley 32 and a V-belt 34, the latter being maintained under tension by a fixed idler pulley 35 and a movable idler pulley as. The pulley 3b is carried on one end of an arm 37 and the other end of the arm is pivoted to the housing 25 and urged inwardly toward the belt 34 by a spring 39.

Power is supplied to the shaft 311 and the pulley 32 by a V- belt pulley d0 secured to the motor shaft M and coupled by a V-belt ill to the V-belt pulley 33. The belt 41 loosely engages the pulleys 33 and did so that power will not be transmitted to the pulley 33 until the clutching pulley 42 is urged against the belt ll as viewed'for instance in FIG. b.

The distance between the drive pulley 410 and the driven pulley 33 is determined by the coupling between the front end of the housing 25 and the frame 10 of the mower. More specifically, the front end of the housing 25 includes a pair of spaced brackets 43 fixedly secured thereto. The frame 10 of the tractor has a pair of depending brackets 44 and a link 45 is pivoted at do to the brackets a3 and at 47 to the depending brackets Mi. Means not shown may be provided to shift the longitudinal position of the housing relative to the frame l0 to adjust the tension of the V-belt ill so that when the clutching pulley $2 is disengaged, power will not be transmitted to the pulley 33. In addition, an adjustable bracket $5 or other suitable means may be provided to adjust the height of the front end of the housing 25. The rear portion of the housing 25 includes a U-shaped bracket i) carrying a pair of wheels 50 supported by an axle 5ll extending through the legs of the U- shaped bracket 49. If desired, the bracket 49 can be pivotally attached to the housing 25 and suitable means may be employed for simultaneously shifting the position of the bracket ill and adjusting the link of the coupling 48 to raise and lower the housing 25.

The clutching pulley d2 is carried by an arm 52 which is secured to the bottom end of a vertically disposed shaft 53 having an operating handle 5 on the top side thereof. The shaft 53 is pivoted at 55 to the frame and is utilized to rotate the arm 52 to move the clutching pulley 42 toward and away from the belt dll. Clutch control means in the form of a spring 56 is connected between the arm 52 and a suitable portion of the frame l0 and normally holds the pulley 42 in the position shown in FIG. 5. In other words, the spring 56 operates as a control means to constantly urge the clutching pulley 62 into a disengaged position.

To maintain the clutching pulley l2 in contact with the belt All and thereby effect transmission of power, manually operated means including a spring 57 is utilized to override the action of the spring 56. In the instant embodiment of the invention this manually operated means includes a vertical shaft 55 extending upwardly through the frame 110 and through the base of the seat 59. The top end of the shaft 58 carries a metal disc 50 and a plate 611 hinged at 62 to the seat 559 overlying the disc 60. A suitable layer of foam rubber or other suitable material 63 may be secured to the top side of the plate 511. From the foregoing it will be observed that the weight of the operator on the plate 61 will move the disc 60 together with the shaft 55 downwardly.

The lower end of the shaft 5% is pivotally secured at 64 to the arm 55 of a bell crank 66 which in turn is pivoted at 67 to a downwardly depending bracket 5% secured to the housing 10. A connecting rod 69 is pivoted at one end to the arm 70 of the bellcrank 66 and at the other end to a link 71 pivotally secured to a bracket 72 carried by the frame 10. The spring 57 is connected at one end to the lower portion of the link 7ll and at the other end to a point on the arm 52 located between the clutching pulley 42 and the point of attachment to the operating shaft 53.

With the invention as described above and assuming depression of the shaft 58 so that it is in the position shown in FIG. 4, the bell crank 66 will be rotated in a counterclockwise position and will pull the link 71 to the left. This stresses the spring 57 so that when the handle 54 on the operating shaft 53 is moved to a disengaged position as shown in FIG. 5, the

springs

56 and 57 will cooperate to hold the clutching pulley 42 out of engagement with the belt 41. Under the same set of conditions, movement of the operating handle 54 to an engaged position will cause the center line of the stressed spring 57 to move to the opposite side of the axis of the operating shaft 53. Since the spring 57 exerts a greater force than the spring 56, it will override the action of the spring 56 and hold the clutching pulley 42 in engagement with the belt 41 to effect transmission of power. Should the operator leave the seat 59, spring 57 will be relaxed whereupon the spring 56 will operate to automatically pull the pulley 42 away from the belt 41 and to the position shown in FIG. 5. if the rod 58 is not in the depressed position, the clutching pulley 42 cannot be maintained in engagement with the belt 41. To effect engagement of the clutching pulley 42 with the belt 41, the shaft 58 must be maintained in the downward position as shown in FIG. 4. If desired,'a suitable adjustment may be provided on the lower end of the shaft 58 and such adjustment may include screw threads 58 threadably engaging a bracket 74 and lock nut 73 so that the vertical position of the shaft 58 may be fixed relative to the bell crank 66.

While only one embodiment of the invention has been illustrated and described, it is apparent that alterations, modifications and changes may be made without departing from the true scope and spirit thereof as defined by the appended claims.

What l claim is:

1. ln a mower having a source of motive power, and cutting means driven by said source of motive power, a safety device for controlling the transmission of power to said cutting means comprising clutching means controlling the transmission of power to said cutting means, clutch operating means for engaging and disengaging said clutching means, control means operable to normally maintain said clutching means in the disengaged position and manually operated means activated in response to the weight of an operator to override the effect of said control means and permit said clutching means to be maintained in the engaged and disengaged positions and upon inactivation of said manually operated means enables said control means to move the clutching means to the disengaged position.

2. In a mower according to claim Ilwherein said control means comprises first spring means holding said clutching means in the disengaged position and said manually operated means includes a second spring and means for stressing said second spring to render the first spring ineffective to disengage the clutching means when said clutching means is moved to the engaged position.

3. In a mower according to claim 2 wherein said clutching means comprises a lever pivoted at one end and carrying a clutching pulley at the other, means including a belt for transmitting power from said power source to said cutting means, said clutching pulley when in engagement with said belt effecting transmission of power and when out of engagement with said belt interrupting transmission of power and said first spring means functions to urge said clutching pulley out of engagement with said belt.

4. In a mower according to claim 3 wherein said second spring is secured at one end to said lever at a point between said pivot and said pulley and at the other end to a support positioned relative to said lever pi vot so that said second spring will shift from one side of said pivot to the other side when said lever and pulley are moved to and from the belt engaging position.

5. In a mower according to claim 4 wherein said clutch operating means comprises manually operated means for moving said lever and clutching pulley into and out of the belt engaging position.

6. In a mower according to claim 2 including an operator's seat carried by said mower, means interconnected with said seat and displaced in response to the weight of an operator in said seat and means coupling the last said means with said second spring whereby said second'spring is stressed by the weight of the operator in said seat and is relaxed when the operator is removed.

7. In a self-propelled riding mower having at least three wheels, a source of motive power for driving at least one of said wheels, cutting means carried by said mower and an operators seat, a safety device for controlling the transmission of power to said cutting means comprising clutching means controlling the transmission of power to said cutting means, control means norrnally urging said clutching means into the disengaged position to interrupt transmission of power to said cutting means, manually operated means for moving said clutch between the engaged and disengaged positions and means responsive to the weight of an operator in said seat for over-riding said control means and permit said clutching means to be retained in the engaged position for driving said cutting means, said clutching means comprising a first pulley coupled to said cutting means, a second pulley coupled to said source of motive power, a belt loosely coupling and in slipping engagement with said pulleys and a third pulley movable to and from a position in engagement with said belt, said third pulley when in engagement with said belt effecting transmission of power from said second pulley to said first pulley, said manually operated means comprises a vertically disposed shaft rotatably mounted for movement about its longitudinal axis, a lever secured at one end to said shaft and carrying said third pulley on the other end thereof, said control means comprises a first spring urging said lever in a direction to move said third pulley away from said belt, and said weight responsive means comprises a second spring connected at one end to said lever, mechanical means associated with said seat and displaced by the weight of the operator and a coupling between the other end of the second spring and said mechanical means, said second spring when said clutching means is disengaged lying on one side of said shaft and when in the engaged position lying on the other side of said shaft whereby actuation of said mechanical means by the weight of said operator stresses said second spring to counteract the force of said first spring when said clutching means is in the engaged position and hold the clutching means in the last said position and to supplement the action of the first spring when the clutching means is in the disengaged position.

Claims

1. In a mower having a source of motive power, and cutting means driven by said source of motive power, a safety device for controlling the transmission of power to said cutting means comprising clutching means controlling the transmission of power to said cutting means, clutch operating means for engaging and disengaging said clutching means, control means operable to normally maintain said clutching means in the disengaged position and manually operated means activated in response to the weight of an operator to override the effect of said control means and permit said clutching means to be maintained in the engaged and disengaged positions and upon inactivation of said manually operated means enables said control means to move the clUtching means to the disengaged position.

2. In a mower according to claim 1 wherein said control means comprises first spring means holding said clutching means in the disengaged position and said manually operated means includes a second spring and means for stressing said second spring to render the first spring ineffective to disengage the clutching means when said clutching means is moved to the engaged position.

4. In a mower according to claim 3 wherein said second spring is secured at one end to said lever at a point between said pivot and said pulley and at the other end to a support positioned relative to said lever pivot so that said second spring will shift from one side of said pivot to the other side when said lever and pulley are moved to and from the belt engaging position.

6. In a mower according to claim 2 including an operator''s seat carried by said mower, means interconnected with said seat and displaced in response to the weight of an operator in said seat and means coupling the last said means with said second spring whereby said second spring is stressed by the weight of the operator in said seat and is relaxed when the operator is removed.

7. In a self-propelled riding mower having at least three wheels, a source of motive power for driving at least one of said wheels, cutting means carried by said mower and an operator''s seat, a safety device for controlling the transmission of power to said cutting means comprising clutching means controlling the transmission of power to said cutting means, control means normally urging said clutching means into the disengaged position to interrupt transmission of power to said cutting means, manually operated means for moving said clutch between the engaged and disengaged positions and means responsive to the weight of an operator in said seat for over-riding said control means and permit said clutching means to be retained in the engaged position for driving said cutting means, said clutching means comprising a first pulley coupled to said cutting means, a second pulley coupled to said source of motive power, a belt loosely coupling and in slipping engagement with said pulleys and a third pulley movable to and from a position in engagement with said belt, said third pulley when in engagement with said belt effecting transmission of power from said second pulley to said first pulley, said manually operated means comprises a vertically disposed shaft rotatably mounted for movement about its longitudinal axis, a lever secured at one end to said shaft and carrying said third pulley on the other end thereof, said control means comprises a first spring urging said lever in a direction to move said third pulley away from said belt, and said weight responsive means comprises a second spring connected at one end to said lever, mechanical means associated with said seat and displaced by the weight of the operator and a coupling between the other end of the second spring and said mechanical means, said second spring when said clutching means is disengaged lying on one side of said shaft and when in the engaged position lying on the other side of said shaft whereby actuation of said mechanical means by the weight of said operator stresses said second spring to counteract the force of said first spring when said cLutching means is in the engaged position and hold the clutching means in the last said position and to supplement the action of the first spring when the clutching means is in the disengaged position.