US2470874A

US2470874A - Propeller guard for outboard motors

Info

Publication number: US2470874A
Application number: US677029A
Authority: US
Inventors: Harry A Sidney
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-06-15
Filing date: 1946-06-15
Publication date: 1949-05-24
Anticipated expiration: 1966-05-24

Description

May 24, 1949. H. A. SIDNEY I 2,470,374

PROPELLER GUARD FOR OUTBOARD MOTORS Filed June 15, 1946 ATTORNEYS Patented May 24, 1949 UNITED STATES PATENT OFFICE PROPELLER GUARD FOR OUTBOARD MOTORS 11 Claims. 1

My invention relates to improvements in propeller guards for outboard motors.

The primary object of my invention is to provide a guard which will effectively cut and deflect weeds from the path of the propeller without materially retarding the motion of the boat with which it is associated.

Numerous attempts have heretofore been made to provide an effective guard for outboard motors, but so far as I am aware, none of the guards heretofore designed have been commercially successful because of their resistance to the motion of the boat, even in clear water, and the greatly increased resistance which they offer to the motion of the boat when in contact with weeds, and their tendency to be deflected by the weeds into contact with the propeller blades.

It is my object to overcome these objections and to provide a commercially successful guard for outboard motor propellers which will have knife-like cutter members capable of moving through the water with minimum resistance and will not become entangled in weeds, but will move with an effective shearing action against any obstacles in its path, whether comprising weeds or submerged tree branches, and in which the blades can have a minimum cross section and capability of instant adjustment to a raised position above the water line when the propeller is operating in water free of weeds.

In general, it is my object to provide a commercially successful weed guard applicable to all outboard motors without material impairment of their efficiency in propelling a boat, and without interference with steering operations,

In the following description, reference is had to the accompanying drawings, in which Figure 1 is a side elevation of the lower portion of the shaft housing of an outboard motor and its propeller wheel, with my improved guard applied thereto.

Figure 2 is a front elevation of the same.

Figure 3 is a plan view of the lower portion of the guard, with its hanger .bar shown in cross section, and a detached propeller wheel illustrated in its proper relation to the extremities of the weed guard fork arms.

Figure 4 is a detail cross section, drawn to line 4-4 of Figure 3.

Figure 5 is a view in side elevation, showing the guard in its elevated inoperative position, with dotted lines indicating an intermediate retracted position.

Figure 6 is a sectional View drawn to line 6-6 of Figure 1.

Like parts are identified by the same reference characters throughout the several Views.

A knife-like hanger i6 is pivotally connected at H to an oscillatory bracket l2 associated with a clamping collar I3 which embraces the vertical shaft housing It of an outboard motor, preferably above normal water line, The hanger I0 is suspended in front of the housing 14 and has a sharp front edge i5 and therefore is adapted to move through the water with minimum resistance. Its lower end is forked to provide two divergent blade-like downwardly, outwardly, and rearwardly curving arms or blades I! and it, which have, respectively, knife-like edges l9 and 20 which face forwardly in their upper portions and laterally in their lower portions. The curvature of these blades is such that their sharp edges will move upon the weeds with a sliding or shearing action and cut them without materially retarding the motion of the boat. Also, in cutting the weeds, they will at the same time deiiect the sheared portions laterally from the path of the propeller.

The rear margins of the hanger l0 and the fork arms I! and is are preferably streamlined as indicated at El, and the rear end portions of the fork blades are preferably in a substantially horizontal position at about the level of the axis of the propeller and sufliciently offset laterall to avoid danger of contact with the propeller wings 22. The free ends 23 of the blades I! and I8 are located only slightly to the rear of the space in which the propeller wings rotate, whereby the slipstream will efiectively carry the weed fragments away. I have found that if these forked blades are extended several inches to the rearof the propeller they interfere with this action of the slipstream and tend to induce eddies, which carry some of the fragments into contact with the propeller Wings. A pair of resilient clips 25, located slightly above the cavitation plate 26, normally holds the hanger ID in its working position.

But when released from these clips, the entire guard may be quickly adjusted to an inoperative position, either by unscrewing the thumb nut 21 from the clamping bolt 28 and detaching the clamping collar l3, or by swinging the hanger H) to a raised inoperative position without disturbing the clamping collar l3. The bracket 12 provides one means for so adjusting the hanger ID to a raised inoperative position.

It will be observed that the upper end portion of the hanger I0 is offset at '29 and the bracket l2 has a correspondingly ofiset pivot stud 3i which is socketed in the clamping collar and serves as an oscillatory pivot for the :bracket, whereby the hanger may be swung past the housing M to the full line position in which it is shown in Figure 5. In either the raised position, or in the normal operative position, it may be locked by a removable pin 32.

Whenthe propeller is to operate in clear water, the pin 32 may be removed to allow the bracket 12 to be oscillated on the collar 13. The hanger Ill may then be swung backwardly on its pivotal connection I i to the position in which it is indicated by dotted lines in Figure 5, whereupon it may be swung laterally and upwardly to the position in which it is indicated in full lines in Figure 5. The hanger if! then rests on a stop 35 which holds it in said raised position. The bracket IE will have been rotated 180, and the stud or stem 3i may then be again locked'to the bracket I3 by reinserting the locking pin 32.

The hanger blade I and its knife-like fork arms El and iii are relatively wide in proportion to their thickness. This not only enables them to cut through weeds and water freely, but their relative width as compared with their thickness prevents them from being bent or deflected in the direction of the propeller.

I claim:

1. A weed guard for an outboard motor having a propeller and an upwardly extending housing member for a propeller driving shaft, comprising the combination with said housing member, of a hanger connected therewith normally in a guarding position in front of the housing, and provided with fork arms diverging from the end of the hanger distant from said pivotal connection laterally, downwardly and rearwardly on opposite sides of the propeller, said fork arms having sharp weed cutting edges.

2. A weed guard as set forth in claim 1, in

which the hanger comprises a blade with a sharp front cutting edge.

3. A weed guard as set forth in claim 1, in which means are provided whereby the guard may be quickly adjusted to an inoperative position when the propeller is operating in water free of weeds.

4. A weed guard as set forth in claim 1, in which means are provided for adjusting the hanger into and out of its normal guarding position to a raised inoperative position.

5. A propeller guard for an outboard motor, comprising the combination with the shaft housing of an outboard motor of a hanger having its upper end portion pivotally supported in front of said shaft housing, said hanger having a sharp weed-cutting front edge, and depending bladelike fork arms extending downwardly, laterally and rearwardly fromthe lower end of the hanger and provided with sharp weed-cuttin edges at their front and laterally facing margins.

6. A propeller guard for an outboard motor, comprising the combination with the shaft housing of an outboard motor of a hanger having its upper end portion pivotally supported in front of said shaft housing, said hanger having a sharp.

weed-cutting front edge, and depending bladed fork arms extending downwardly, laterally and rearwardly from the lower end of the hanger and provided with cutting edges at their front and laterally facing margins, the free extremities of said fork arms being located at the respective sides of the path of the propeller and slightly to the rear of the space in which the propeller revolves.

7. A weed guard for an outboard motor, comprising a hanger member provided with means for supporting it in front of the propeller shaft housing of an outboard motor, and divergent blades connected with said hanger and extending from the lower end thereof downwardly, laterally and rearwardly in positions for guarding the path of a propeller associated with the housing in front of which the hanger is supported, said blades having forwardly directed cutting edges.

8. A weed guard for an outboard motor, comprising the combination of a clamping collar adapted to embrace the vertical shaft housing of an outboard motor, of a bladed hanger having its upper end connected with said collar and its lower end forked and extending in the form of downwardly and laterally divergent and rearwardly curving fork arms provided with cutting edges for contact with weeds in the path along which the motor advances.

9. In a combination as set forth in claim 8, an oscillatory bracket mounted on said collar, a pivotal connection between said bracket and hanger, and means for locking the bracket with the hanger either in working position or in a raised inoperative position.

10. A weed guard for an outboard motor com prisin the combination with an outboard motor housing member, of a hanger pivotally connected with said housing member and adjustable thereon to either a raised inoperative position or a depending guarding position, the end of said hanger distant from said pivotal connection having divergent bladed fork arms adapted, when the hanger is in guarding position, to extend downwardly, outwardly and rearwardly on opposite sides of a propeller wheel associated with said outboard motor, said arms having weed cutting edges substantially as described.

11. A weed guard for an outboard motor having a housing and a propeller supported thereby, comprising the combination with a mounting bracket for connection with said housing, of a weed guard connected with the bracket for support in a propeller guarding position and comprising a pair of blades connected together in substantial parallelism at their upper ends and divergent downwardly and rearwardly before the propeller, the divergent lower ends of the blades bein provided with sharp weed cutting edges.

HARRY A. SIDNEY.

REFERENCES CITED UNITED STATES PATENTS Name Date Arado Aug. 15, 1944 Number