US3433002A - Motorized friction drive mower - Google Patents

Description

Maid! 1969 R. J. CUSTANCE MOTORIZED FRICTION DRIVE MOWER Sheet Filed NOV. 1, 1965 March 18, 1969 R. J. CUSTANCE MOTORIZED FRICTION DRIVE MOWER Z of 3 Sheet Filed NOV. 1, 1965 FIGZ March 18, 1969 R. J. CUSTANCE MOTORIZED FRICTION DRIVE MOWER Sheet 3 of 3 Filed Nov. 1. 1965 3,433,002 MOTORIZED FRICTION DRIVE MOWER Raymond J. Custance, 47 Te Ante Road, Haveiock North, Hawkes Bay, North lsiand, New Zealand Filed Nov. 1, 1965, Ser. No. 505,859 Claims priority, application Sweden, Nov. 10, 1964,

13,537/64 Us. (:1. 56-26 11 Claims rm. (:1. A01d 35/24 ABSTRACT OF THE DISCLOSURE This invention relates to motorized mowers of the kind having a body which is supported on ground wheels and carries both a rotating or reciprocating cutter and a motor, such as an electric motor or an internal combustion engine. The motor both propels the wheels and drives the cutter.

In accordance with the present invention, the body of a motorized mower of the kind described is supported on four ground wheels, one at the front and rear on each side, with the wheels on each side of the body being driven through a common friction roller which rests on and between the two wheels.

This arrangement calls for a short front to rear wheel base so that the friction roller on each side can rest in the V formed between the front and rear ground wheels. The machine can therefore be made very compact and this results in easy maneuvering and storing. The friction drive is cheap, positive, easily controlled and drives all four wheels at the same time. By having all the four wheels driven, the machine can be used in rough and wet conditions without appreciable slipping because there are always three wheels in contact with the ground and these are all capable of propelling the machine.

The friction roller on each side of the body may be rotatably mounted on a pivoted support member which can rock to bring the friction roller into and out of engagement with the ground wheels without affecting the drive to the friction roller, with the two support members being resiliently urged in directions to bring the friction rollers into engagement with the ground wheels but being arranged upon operation of a manual control member to move against the spring loading to disconnect the drive to the wheels. This feature enables the positive drive to the ground wheels to be disconnected without affecting the drive to the cutter so that, if necessary, the machine can be inspected stationary with the cutter running or manipulated by hand to cut rough grass in inaccessible positions.

When the mower is of the conventional design having a handle which extends upwardly and rearwardly from the body for gripping by a pedestrian operator walking behind the mower, the handle preferably forms the manual control member and includes two legs which pass and are movably mounted one on each side of the body and are connected to the pivoted support members in such a way that when the handle is pulled backwards or downwards the support members rock so that the friction States 1 atent Q rollers move out of engagement with the ground wheels and the drive to the ground wheels is disconnected, and when the outer end of the handle is pushed forwards or upwards, the drive is re-engaged. If the weight of the handle is incompletely counter-balanced by the spring loading on the support members, when the outer end of the handle is released by a pedestrian operator for any reason, the handle will fall backwards and downwards under its own weight and cause automatically the disengagement of the drive to the ground wheels. The handle then forms in effect a dead mans handle which prevents the mower from running away if it is released by an operator who for example stumbles.

The handle legs may be pivoted directly on the body and be connected to the support members by a pin and slot connection, but preferably the handle legs are pivoted to the support member and are loosely guided in guides on the body.

The pivoted support members on the two sides of the body may be rigidly interconnected so that they rock together and the two friction rollers may then be driven by a common axle on which they are mounted. In order to allow over-riding of the driven axle from the ground wheels when the friction rollers are in engagement with the ground wheels, a pawl and ratchet mechanism may be interposed between each friction roller and the common axle.

When the common axle is provided, it may carry at one side of the body a sprocket wheel which is driven by a chain passing around a second sprocket wheel which is freely rotatable about an axis coincidental with the pivotal axis of the support members, with the second sprocket wheel being rigidly connected to a third sprocket wheel which is driven by a second chain through which the cutter is driven from the motor.

The friction rollers may be provided with peripheral teeth which mesh with similar teeth on at least one of the ground wheels on each side of the body. The teeth on the ground wheels may be formed by part of the tread of the tires and when only one of the front and rear ground wheels are provided with teeth, it is preferably the front wheels which are so provided.

The invention is particularly appliacble to a mover of the kind in which the cutter is a cylindrical reel fitted with a number of axially extending helical blades which co-operate with a fixed ledger blade at the bottom of the body. The reel may then be rotatably mounted on a transverse axis extending between the front ground wheels of the machine. With this arrangement, there is a space provided behind the cutter reel between the rear ground wheels and a grass catcher may be fitted in this space so that the grass cuttings are thrown upwardly and rearwardly by the cutter reel into the grass catcher. Since the grass catcher starts from within the wheel base of the mower, the arrangement is particularly compact and there is little danger of the catcher getting in the Way of the pedestrian operators feet as he walks behind the mower.

When the cutter reel is of this form, in order to be able to set the height of the cutter above the ground, the two ground wheels on each side of the body may be freely rotatable on the stub axles projecting laterally from a bar which extends along the side of the body, with the rear end of the bar being pivoted to the body and the front end of the bar being selectively secured to the body in any one of a number of positions at different heights relatively to the body.

One example of a motorized mower constructed in accordance with the present invention is illustrated in the accompanying drawings in which:

FIGURE 1 is a perspective view of the mower without its grass catcher;

FIGURE 2 is a plan view of the body of the mower;

FIGURE 3 is a front elevation of the body of the mower;

FIGURE 4 is an elevation of the left hand side of the mower body with parts broken away; and,

FIGURE 5 is an elevation of the right hand side of the body with other parts broken away.

As shown most clearly in FIGURE 1, the mower has a body with a chassis formed by a deck plate 6 to which side plates 7 and 8 are welded. An internal combustion engine 9 of conventional design is mounted on top of the deck plate 6 and is arranged to drive a cutter reel 10 and front and rear ground wheels 11 and 12 through a centrifugal clutch 13. A throttle control 14 for the motor is adjacent to the free end of a handle 15 having a pair of legs 16 which extend one on each side of the body of the mower.

The cutter reel 10 has a central axle 17 and the ends thereof are rotatable in bearings 18 carried on the inner surfaces of the side plates 7 and 8. The axle 17 extends right through the bearing 18 carried by the plate 8 and has rigidly fixed on its end a sprocket wheel 19. The sprocket wheel 19 and hence the cutter reel 10 are driven from a sprocket wheel 20 on the output shaft of the centrifugal clutch 13 by a chain 21 housed within a guard 22.

The helical blades of the cutter reel 10 co-operate with a stationary ledger plate 23 which extends between the bottom edge of the side plates 7 and 8. At each side the ledger plate 23 carries a bracket 24 which is bolted to the side plates 7 and 8 by bolts 25 and 26. The bolts 25 each extend through an off center hole in a block 27 which is rotatable in the corresponding side plates 7 and 8 and the height of the ledger palte 23 relatively to the cutter reel 10 can be adjusted by loosening the bolts 25 and 26 and rotating the blocks 27 to the necessary extent. The bolts 26 pass through elongated slots 28 in the side plates 7 and 8 to allow for any longitudinal movement of the ledger plate 23 consequent upon rotation of the blocks 27. When the adjustment has been made, the bolts 25 and 26 are retightened again.

The ground wheels 11 and 12 on each side of the mower body are freely rotatable on stub axles 29 and 30 respectively which are fixed to a bar 31 the rear end of which is pivotally mounted by means of a bolt 32 to the corresponding side plate 7 or '8 and the front end of which is secured by means of a bolt 33 to the corresponding side plate. The bolts 33 are arranged to extend through any one of a number of part circular holes 34 at the front ends of the side plates and this enables an adjustment in the height of the front end of the bar 31 relatively to the body of the mower, and hence an adjustment in the height of the cutter reel 10 and ledger plate 23 above the ground, to be made. The bars 31 on each side of the mower body are similar although the bar on the left hand side of the machine has wider return portions 35 and the corresponding bolt 33 requires a spacer 36, in order to accommodate the driving mechanism which is positioned on the left hand side of the body.

The drive to the ground wheels 11 and 12 is also transmitted through the chain 21 which, as well as passing around the sprocket wheels 19 and 20 also passes with its outer surface in engagement with a further sprocket wheel 37. The sprocket wheel 37 is rigidly fixed on a sleeve 38 that is freely rotatable on a bearing carried by a bolt 39 extending through the guard 22 and through the side plate 8. Immediately inside the side plate 8 one end of a supporting arm 40' is pivotally mounted on the bolt 39 and immediately within the side plate 7 is a further identical arm 40 having an end which is pivotally mounted on a bolt 41 which extends through the side plate 7 coaxially with the bolt 39. Rigidly interconnecting the two arms 40 is a bearing tube 41a through which a shaft 42 extends, and the ends of the shaft 42 extend through openings 43 in the side plates 7 and 8 and carry toothed friction rollers 44 in the V formed between and above .4 the ground wheels 11 and 12 on each side of the body. Between the side plate 8 and the adjacent friction roller 44-, the shaft 42 has keyed thereon another sprocket wheel 45 which is driven from a further sprocket wheel 46 fixed on the sleeve 38 through a chain 47 within a guard 48.

The assembly of two supporting arms 44), the transverse tube 41a, and the shaft 42, are urged to pivot about the bolts 39 and 41 backwards and downwards under the action of hairpin tension springs 49 which are spaced at intervals across the body and are interposed between a shield plate 50 for the cutter reel 10, the deck plate 6, and the top of the tube 410. The extreme lower ends of the legs 16 of the handles 15 are formed by flat bars 51 one of which extends loosely through a guide channel 52 carried by the right hand bar 31 and which are sprung over and pivotally connected to studs 53 projecting outwards through the corresponding openings 43 from lugs 54 on the corresponding supporting arms 40.

When the handle 15 is pulled backwards or downwards, its legs slide backwards through the channel 52 and this causes the assembly of supporting arms 40, tube 41a, shaft 42, and friction rollers 44 to swing upwards about the axis of the bolts 39 and 41 to the position shown in FIGURE 5 in which the friction rollers 44 are clear of the ground wheels 11 and 12. Indeed, the weight of the handle 15 is such that if it is released its weight is sufiicient to overcome the reaction of the springs 49 and to cause the assembly to swing upwards to this inoperative position. In this inoperative position, the cutter reel 10 is still driven through the chain 21, provided that the engine 9 is running fast enough to engage the centrifugal clutch 13, and since the axis of the bolts 39 and 41 about which the assembly swings upwards is coincidental with the axis of rotation of the sprocket wheels 37 and 46, the drive to the friction rollers 44 through the chain 47 and sprocket wheel 45 is unaffected. Upward movement of the assembly is limited by the engagement of the top edge of the right hand stud 53 with a bracket 55 fixed to the corresponding bar 31.

In order to engage the drive to the ground wheels, the handle 15 is pushed forward or at least lifted sufficiently for the reaction of the springs 49 to pivot the assembly downwards and backwards so that the friction rollers 44 engage both the ground wheels 11 and 12 on each side of the body. The solid rubber tires on the front ground wheels 11 are provided with a toothed tread of the same pitch as the teeth on the friction rollers 44 to assist in transmitting the drive to the ground wheels 11 at least. Pawl and ratchet mechanisms are fitted between the friction rollers 44 and the shaft 41 in such a way that a forward drive is transmitted by the pawl and ratchet mechanisms from the engine 9 to the ground wheels but the ground wheels can overrun the drive, for example, the outer pair of ground wheels when turning. It will be appreciated that the cutter reel 10 is driven in the same direction as the ground wheels 11 and 12 because there are two reversals in the direction of the drive between the sprocket wheel 20 and the ground wheels. One reversal is caused by the engagement of the back of the chain 21 with the sprocket wheel 37 and the other is provided by the interposition of the friction rollers 44 themselves. The positions of the axis of the shaft 41a and the pivotal axis of the supporting arm assembly relatively to the axis of the axles 29 and 30 and the center of pivoting of the bolt 32 is such that the adjustment to the bars 31 provided by the bolts 33 and holes 34 has negligible effect on the even engagement between the friction rollers 44 and the front and rear ground wheels 11 and 12.

The cutter reel 10 extends between the front ground wheels 11 and as suggested in FIGURES 2 and 4, the space behind the cutter reel between the rear ground wheels 12 can be fitted with a grass catcher 56 into which the grass is thrown by the reel 10 and which can be removed for emptying. The grass catcher 56 is fitted to the mower body by means of lugs 57 which lip under flanges on the brackets 24 while central bottom portions of the sides of the catcher rest on spacer 58 carried on the bolts 32.

I claim:

1. A motorized mower comprising a body having sides and four ground wheels, one at the front and rear of each side, cutter means carried by the body, a pivoted support member on each side, a driving friction roller rotatably mounted on the support member, biasing means for urging the support member in a direction to move the friction roller into joint contact with the two wheels on that side of the body, drive means for the friction roller, and means for moving the support member in another direction to remove the friction roller from said contact, with the drive to said friction roller being un ffected by the movement of said support member.

2. The mower according to claim 1, in which said means for moving said support member is a handle which extends upwardly and rearwardly from the body for gripping by a pedestrian operator walking behind the mower, the handle including two legs which pass and are movably mounted one on each side of the body and are connected to the pivoted support members in such a way that when the handle is pulled backwards or downwards, the support members rock so that the friction rollers move out of engagement with the ground wheels and the drive to the ground wheels is disconnected, and when the outer end of the handle is pushed forwards or upwards, the drive is re-engaged.

3. The mower according to claim 2, in which the weight of the handle is such as to overcome a spring loading on the support members whereby when the outer end of the handle is released by a pedestrian operator, the handle falls backwards and downwards under its own weight and causes automatically the disengagement of the drive to the ground wheels.

4. The mower according to claim 3 including guides on the body and said handle legs being pivoted to the support members and loosely guided in said guides.

5. The mower according to claim 1, in which the pivoted support members on the two sides of the body are rigidly interconnected so that said members rock together and a common axle on which the two friction rollers are mounted and driven.

6. The mower according to claim 5, in which a pawl and ratchet mechanism is interposed between each friction roller and the common axle so that overriding of the axle from the ground wheels is possible when the friction rollers are in engagement with the ground wheels.

7. The mower according to claim 6, in which the common axle carries at one side of the body a sprocket wheel which is driven by a chain passing around a second sprocket wheel which is freely rotatable about an axis coincidental with the pivotal axis of the support members, and the second sprocket wheel being rigidly connected to a third sprocket wheel which is driven by a second chain through which a cutter is driven from the motor.

8. The mower according to claim 1, in which the friction rollers are provided with peripheral teeth which mesh with smaller teeth on at least one of the ground wheels on each side of the body.

9. The mower according to claim 1 including a cutter defined by a cylindrical reel fitted with a number of axially extending helical blades and a fixed ledger blade at the bottom of the body with which said blades cooperate, the reel being rotatably mounted on a transverse axis extending between the front ground wheels.

10. The mower according to claim 9, including a bar extending along each side of the body, stub axles projecting laterally from each bar, the ground wheels on each side being freely rotatable on the stub axles, the rear end of the bar being pivoted to the body and the front end of the bar being selectively secured to the body in any one of a number of positions at different heights relatively to the body whereby the height of the cutter above the ground can be set.

11. The mower according to claim 10, in which a grass catcher is fitted in the space behind the cylindrical reel between the rear ground wheels so that grass cuttings thrown upwards and rearwardly by the cylindrical reel enter the grass catcher.

References Cited UNITED STATES PATENTS 2,380,181 7/1945 Krenzien -74 2,474,085 6/1949 Albright 180-19 2,623,603 12/1952 Cutlan et al. 180-19 2,645,300 7/1953 Watts et al. 180-76 2,742,973 4/1956 Johannesen 180-19 X 2,823,507 2/1958 Cooper et al. 5625.4 2,824,415 2/1958 Frazier 180-19 3,003,300 10/1961 Jepson 56-26 3,035,385 5/1962 Lill 56-25.4 3,068,632 12/1962 Postlewatt et al. 56-26 3,343,621 9/1967 Van Doorne 180-74 ALDRICH F. MEDBERY, Primary Examiner.

US. Cl. X.R.

Images