US3039724A

US3039724A - Outboard motor manipulating mechanism

Info

Publication number: US3039724A
Application number: US25780A
Authority: US
Inventors: Robert A Herreman
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-04-29
Filing date: 1960-04-29
Publication date: 1962-06-19
Anticipated expiration: 1979-06-19

Description

June 19, 1962 R. A. HERREMAN 3,

OUTBOARD MOTOR MANIPULATING MECHANISM Filed April 29. 1960 4 Sheets-$heet 1 INVENTOR.

ROBERT A. HERREMAN BYWd AT TORNEX FIG.

June 19, 1962 R. A. HERREMAN 3,03 ,724

OUTBOARD MOTOR MANIPULATING MECHANISM FIG.3

INVENTOR.

ROBERT A. HERREMAN ATTORNEY June 1-9, 1962 R. A. HERREMAN 3,039,724

OUTBOARD MOTOR MANIPULATING MECHANISM Filed April 29. 1960 4 Sheets-Sheet 3 INV EN TOR.

ROBERT A. HERREMAN BY ATTORNEY June 19, 1962 R. A. HERREMAN 4 OUTBOARD MOTOR MANIPULATING MECHANISM Filed April 29. 1960 4 Sheets-Sheet 4 t H WII/I; H a b /44 F I G. 6

INV EN TOR.

ROBERT A. HERREMAN FIG. 8 7

ATTORNEY United States Patent 3,039,724 OUTBOARD MOTOR MANIPULATING MECHANISM Robert A. Herreman, 1402 Chester St., South Bend, Ind. Filed Apr. 29, 1960, Ser. No. 25,780 11 Claims. (Cl. 248-4) The present invention relates to a positioning mechanism for boat motors and more particularly to 'a mechanism for lowering and raising outboard motors to and from operating position.

In the past few years outboard motors have been increased in size, weight and horsepower to the extent that they have become extremely diflicult to raise from their normal operating position to a locked position above the water level and also diflicult to lower to operating position without permitting the motor literally to fall from its normal locked position above the water. Even for people capable of lifting and lowering the motor, these operations constitute a considerable hazard in that the operator is required to stand in the boat and/ or lean over the transom of the boat in order to have a secure grip on the motor for the lifting and lowering operations. Walking to and from the motor is also often required in that the boats on which these large motors are used are normally piloted from a place toward the forward end of the boat, thus presenting an additional hazard for the operator of the boats with the large motors. Various types of motor lifting and lowering devices have been tried, including manual, hydraulic and electrical mechanisms, but these prior devices have either been expensive to build and install, dificult in themselves to operate to raise and lower the motor, or are not safe to the average non-professional and often inexperienced boat operator. It is therefore one of the principal objects of the present invention to provide an apparatus for raising and lowering outboard motors, which can be operated by a simple, easily actuated control device located at a point in the boat remote from the motor and which does not interfere with the normal operation and control of the motor while the motor is in its lowered position.

Another object of the invention is to provide an outboard motor lifting and lowering apparatus which can be operated with no appreciable physical force or movement on the part of the operator and which can be effectively controlled by the operator in a sitting or confined position within the boat.

Another object of the invention is to provide an outboard motor lifting and lowering apparatus, which is simple in construction and operation and which can be readily installed on any conventional outboard without cutting, drilling or otherwise changing the construction of the boat transom other than securing parts of the apparatus to the boat using only a few relatively small screws or bolts.

Still another object of the invent on is to provide an outboard motor lifting and lowering apparatus which locks the motor in its raised position automatically as the motor is controlled at a point in the boat remote from the motor, and which automatically releases the motor at the will of the operator and gently lowers the motor to its normal operating position.

A further object is to provide a mechanism of the aforesaid type which can be temporarily installed on a boat and easily removed therefrom along with the outboard motor, and which does not occupy any otherwise normally usable space in the boat.

Another object of the invention is to provide a motor manipulating mechanism for tiling outboard motors between their operating and nonoperating positions, which applies a balanced thrust against the lower portion of the motor to raise the motor from the water, and which Patented June 19, 1952 retracts away from the motor when the present mechanism is not in use.

Additional objects and advantages will become apparent from the following description and accompanying drawings, wherein:

FIGURE 1 is a side elevational view of a boat having mounted thereon an outboard motor and my motor lifting and lowering mechanism;

FIGURE 2 is an enlarged partial top plan and cross sectional view of the boat, motor and my mechanism shown in FIGURE 1, the section being taken on line 2-2 of FIGURE 1;

FIGURE 3 is an enlarged fragmentary and partial cross sectional View of my motor lifting and lowering mechanism, showing it mounted on the transom of the boat;

FIGURE 4 is a side elevational view of an outboard motor and my lifting and lowering mechanism mounted in running position on the transom of a boat;

FIGURE 5 is a side elevational view of the outboard motor and the lifting and lowering mechanism with the motor being held in its lifted position by the mechanism;

FIGURE 6 is a vertical cross sectional view of the control unit for the present motor lifting and lowering mechanism;

FIGURE 7 is a fragmentary vertical cross sectional view of a locking mechanism for holding the motor in its lifted position, the section being taken on line 77 of FIGURE 2; and

FIGURE 8 is a horizontal cross sectional view of the locking mechanism, taken on line 8-8 of FEGURE 7.

Referring more specifically to the embodiment of my invention illustrated in the drawings, numeral 10 designates an outboard motor boat having a transom 12 on which an outboard motor 14 is shown mounted in its lowered position in F iGURES l and 2 for propelling the boat, and in its raised position out of the Water in FIGURE 5. The boat is adapted to be piloted from a seat 16 located forward in the boat, by a steering wheel 13 mounted on a steering mechanism connected to motor 14 by suitable cables and pulleys (not shown) attached to the boat structure. One or more additional seats may be provided in the boat to the rear of seat 16, including one at the rear of the boat adjacent transom 12, without interfering with the installation of my mechanism. For the purpose of the present description both the boat and outboard motor may be considered as conventional and the present invention is not limited in its application to any particular kind or make of outboard motor, the one shown being, for example, a forty horsepower unit consisting of a motor enclosed in a housing 29 and connected to a propeller 22 by a drive shaft disposed in a leg 24 rigidly connected at its upper end to the motor frame or supporting housing 20 and terminating at its lower end in a rudder 25. The outboard motor, which term hereinafter refers to the entire unit unless otherwise specified, is mounted on the boat transom 1.2 by a mounting device 26 including a swivel bracket 28 secured to the motor and a stern bracket 30 pivotally connected to bracket 28. The swivel bracket 28 holds the motor so that it can be oscillated on an upright axis for steering. The stern bracket 3%} is adapted to seat over the top of transom 12 and to be secured thereto by a plurality of clamping units 32 consisting of a shaft 34 threadedly received in a portion of bracket 36] and a bandle 36 for rotating the clamp. The pivoting of the swivel bracket relative to the stern bracket permits the motor to be tilted downwardly into operating position as shown in FIGURES l and 4. In conventional mountings of this general type a thrust receiving member 1 adjustable to various positions receives the forward thrust from the swivel bracket and transmits the propelling force of the motor to the boat.

Most of the more expensive models of outboard motors are equipped with a latching mechanism for locking the motor in its upright operating position so that the operation of the motor can be reversed without the motor tilting upwardly from the water. While the mechanism for locking the motor in its operating position may be considered conventional and is therefore not disclosed in detail herein, a lever for manually operating the latching mechanism is shown at numeral 44, said lever being moved downwardly to release the latch mechanism to permit the motor to be tilted from the water.

The embodiment of my outboard motor raising and lowering mechanism shown in the drawings consists of a power lifting unit 59 and power control and

supply units

52 and 54, respectively,

unit including cylinders

56 and 58 projecting rearwardly from the transom of the boat on opposite sides of the outboard motor positioned approximately half waydown leg 24. The cylinders are rigidly connected to one another by a U-shaped saddle 60 of which arm 62. is secured to cylinder 56 by bolts 64 and 66 and arm 63 to cy inder 58 by bolts 73 and 72.. The two arms are connected by a cross member 74 which is adapted to contact the adjacent side of leg 24 when the lifting unit is operated. The cylinders are substantially the same and are closed by end caps 75 and 76 and cylinder 56 contains a piston 78 and rod 8i; connected to the rear of the transom by a bracket 82, and cylinder 53 contains a piston se and rod 86 connected to the transom by a bracket 37. The two brackets are secured to the rear side of the transom by suitable screws extending into the transom and are pivotally connected to rods 8% and 36 by pins 88 and al respectively. Each rod contains a longitudinal passage 92. extending from the piston end through most of its length and connects the outer end of the cylinder with atube 94, which in turn is connected by a tube 96 to control unit 52 and thence by a tube 98 to power supply unit 54. In order to prevent a sudden sunge of power into the cylinders when the cylinders are actuated by a supply of compressed gas, restrictions 1% and 1&2 are preferably included in tube 94 adjacent rods 3% and 8d and a still further restriction 3.04 in tube 96. Pistons 7'8 and 34 may be of any well known conventional design, the type shown in the drawings consisting of a washer 196 seated against a shoulder 16% on the piston rod, and a cup shaped gasket Tilt? clamped against the Washer by a second washer 112 nut 114 threaded on to the end of the rod. in order to prevent excess pressure from being built up the two cylinders by gas supplie from the source 54, a vent hole 116 is placed in the side wall of each cylinder at the end of the power stroke to relieve the pressure and to form an effective stop for limiting the travel of the piston in the cylinder. As used in the specification and claims, the term rear end of the piston 'efers to the right hand end as seen in the drawings.

The saddle oil is held in the desired position on the motor leg 24 by support rods 11% and 1 pivotally connected to cylinders as and 53, respectively, and pivotally connected to the transom near the top thereof by suitable brackets. These two rods, one of which may be dispensed with if desired, cause the saddle to pivot upwardly and follow the tilting motor as the pistons are extended during the power stroke, as illustrated in EG- URE 5. Rods 118 and fill also hold the saddle in a horizontal inoperative position after the motor has been lowered to running position in the water.

The two cylinders are operated by compressed gas, for example carbon dioxide, from a steel cylinder 13d of power supply unit 54. Cylinders 1 are available as filled exchangeable units, or they can be readily filled with compressed carbon dioxide, air or other suitable gas at readily available stations. Cylinder 130 is held in place in the boat by any suitable clamping means 132 and is connected to control unit 52 by a rubber or copper tube 98, the flow of gas from the cylinder being controlled by a shut-off valve 136 which is mounted on the cylinder and is removed from tube @3 when the cylinder is removed for refilling or replacement by a full cylinder.

Control unit 52 consists of a valve body 149 having an inlet passage 142 connected to tube 98, an outlet passage 144 connected to tube 95, and a passage 146 connecting asid inlet and outlet passages and containing a valve res consisting of a reciprocable valve element 15% with an enlarged end 152 for seating on valve seat 154, and a stem 156 actuated by a lever 153 pivoted at one side of the stem and engaging the upper end of the stem. The valve element is urged to its seat by a spring 1559 around stem 15s and by pressure from cylinder 13%, and is readily opened by the operator by pressing downwardly on the free end 169 or lever 158. The outlet passage is connected to the atmosphere by an exhaust valve led consisting of a valve element 366 urged to its seat 163 by the pressure in the outlet passage and by a spring 17% around stem 172 of the valve. The valve is operated when cylinders 56 and 5?: are to be exhausted, by pressing on a button 174 on the outer end of stem 172. The control unit 56 may be connected directly to the outlet conduit of cylinder 13%, thus eliminating tube 98. A mechanism 18% for automatically locking cylinders 56 and S8 in their extended position and the motor in its raised position, is shown in FlGURES 7 and 8. Mechanism 1% consists of a housing 182 secured to the inner end of cylinder 56 and having a cylindrical chamber 184 in which is mounted a plunger 186. The plunger projects from the housing into a recess 138 in rod 3d and forms a stop for the laterally extending shoulder 1% of recess 15% to hold the rod in its extended position. The plunger is removed from the slot by again energizing the piston to move the rod further to the right, as shown in FIGURE 7, and thereby forces the inclined surface 191 against the plunger causing the plunger to retract into housing 182. In order to hold the plunger in its retracted position, a sleeve 192 in which the plunger reciprocates is provided with a pair of deep op osed slots 1% and a pair of shallow opposed slots 1% in the inner edge thereof, and the inner end of the plunger is provided with a transverse pin 193 for seating in corresponding slots. The plunger is rotated a partial revolution each time it is retracted by engaging a pair of annular toothed members 2% and 202 on the inner end of plungerlSd and a sleeve 264 secured to the end of housing 182 in axial alignment with the plunger. The pitch of the teeth on the members 2% and 2% is such that plunger 1% is rotated sufliciently to shift pin 19% alternately from the deep slots to the shallow slots. The longitudinal movement of plunger 136 for engaging and rotating the plunger is obtained by a lug 2% secured to rod 89 and having an inclined surface continuing outwardly from inclined surface 191. When the pin is in deep slots 194 the plunger extends into recess 138 and locks rod 86 in its extended position, and when the pin is in the shmlow slots 196 the plunger is held in its retracted position free of rod 8%. A longitudinal groove 21% is provided in the end cap to permit lug 2th, to move into the outer end of the cap. Only one locking mechanism 18% is preferably used since one mechanism performs the function of holding both rods 8% and 86 extended and avoids the need of synchronizing the two mechanisms.

In the operation of the present outboard motor lifting and lowering mechanism, when it is desired to lift the motor from its running position shown in FIGURE 4, lever 158 is pressed downwardly by the operator, opening valve element 148 and admitting compressed gas from cylinder 136 and tube 98, through tubes and ?4, and passage 92 of rods 89 and into the rear end of

cylinders

56 and 58. The pressure of the gas in the cylinders forces the cylinders and saddle 6t outwardly to the rear, tilting the motor from the position shown in FIGURE 4 to the position shown in FIGURE 5. The movement of the cylinders continues outwardly until the rear edge of the piston reaches port 116. Since the cylinders at this port have reached their maximum travel, the operator releases lever 158 shutting oif the supply of compressed gas to

cylinders

56 and 58 and permitting them to retract to the point where plunger 186 seats in recess 188 against shoulder 199 holding the cylinders in their extended position and the motor in the position shown in FIGURE 5. When it is desired to release the motor and lower it to its running position, the operator first presses lever 158 again to admit gas into the cylinders and move the cylinders to the point at which lug 203 will force plunger 186 upwardly against member 202 and rotate the plunger sutficiently for pin 198 to seat in the shallow slots 196. The cylinders are now free to return to their inoperative position shown in FIGURE 4. The rate at which the motor is lowered is regulated by controlling exhaust valve 164.

From the foregoing description of the operation it is seen that the entire lifting, locking, unlocking and lowering operations can be fully performed by the manipulation of lever 158 and button 174, i.e. by opening and closing easily operated valves 148 and 164, without any need for the boat operator to leave his seat or to apply any appreciable pressure or use any appreciable physical movement. The simplicity and ease of operation of the control unit add greatly to the safety of the operator and other occupants of the boat in that it is not necessary for the operator to move around in the boat in order to operate the present mechanism either to raise or lower the motor. This important feature is in part made possible by the use of the compressed gas cylinder as the source of power since the operating pressure is provided without employing any moving parts and without the use of any complicated, dilficult to handle control levers or mechanisms. Further, the cylinder of compressed gas is not affected by water or changes in atmospheric condition and can be placed in normally unused space in the boat without danger of fire or explosion.

Since some outboard motors rotate on their vertical axis 360 degrees for reversing the direction of the boat, the motors include a mechanism for locking them in their running position, as explained previously herein. While these motors are usually operated with this mechanism in its unlocked position and hence are in condition to be tilted using the mechanism previously described, it may be desirable in some instances to include a penumatic means operated by the same control unit 52 to unlatch the locking means the instant pressure is admitted into

cylinders

56 and 58. A mechanical means independent of the present motor tilting mechanism may be used instead. While

cylinders

56 and 58 are preferably mounted on saddle 60 and

rods

80 and 86 attached to the transom, this arrangement may be reversed if desired. Various other additions, modifications and changes may be made in the present mechanism without departing from the scope of the invention.

I claim:

1. A mechanism for raising and lowering an outboard motor having a frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the transom of a boat including a pivot forming a horizontal axis on which the motor tilts between operating and nonoperating positions, said mechanism comprising a U-shaped saddle the cross member of which extends horizontally between the transom and the leg of the motor and the arms of which extend rearwardly along opposite sides of the leg, a cylinder secured to each arm and arranged parallel therewith, a piston in each cylinder, a rod in each cylinder attached to the piston and extending from the forward end of the cylinder and having a passage therein communicating with the rearward end of the cylinder, means for pivotally attaching one end of each rod to the boat transom, a cylinder of compressed gas, a conduit connecting said gas cylinder with said passages in said rods, a valve in said conduit for controlling the flow of gas from said gas cylinder to said first mentioned cylinders, an exhaust valve in said conduit between said control valve and said first mentioned cylinders, a shut ofi valve in said conduit between said compressed gas cylinder and said control valve, a pair of restrictions in said conduit between said exhaust valve and said first mentioned cylinders, a means for locking one of said piston rods in its extended position and the U- shaped saddle in its motor lifted position including a recess in said one rod, a plunger for seating in said recess, a lug for retracting said plunger from said recess as said rod is extended, means for alternately placing said plunger in its retracted and extended positions for locking and releasing said one rod, and a rod attached to one of said first mentioned cylinders for holding said saddle in its operating position.

2. A mechanism for raising and lowering an outboard motor having a frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the transom of a boat including a pivot forming a horizontal axis on which the motor tilts between operating and nonoperating positions, said mechanism comprising a U-shaped saddle the cross member of which extends horizontally between the transom and the leg of the motor and the arms of which extend rearwardly along opposite sides of the leg, a cylinder secured to each arm and arranged parallel therewith, a piston in each cylinder, a rod in each cylinder attached to the piston and extending from the forward end of the cylinder and having a passage therein communicating with the rearward end of the cylinder, means for pivotally attaching one end of each rod to the boat transom, a cylinder of compressed gas, a conduit connecting said gas cylinder with said passages in said rods, a valve in said conduit for controlling the flow of gas from said gas cylinder to said first mentioned cylinders, an exhaust valve in said conduit between said control valve and said first mentioned cylinders, a means for locking one of said first piston rods in its extended position and the U-shaped saddle in its motor lifted position including a recess in said one rod, a plunger for seating in said recess, a lug for retracting said plunger from said recess as said rod is extended, means for alternately placing said plunger in its retracted and extended positions for locking and releasing said one rod, and a rod attached to one of said first mentioned cylinders for holding said saddle in its operating position.

3. A mechanism for raising and lowering a boat motor having a frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the rear of a boat including a pivot forming a horizontal axis on which the motor tilts between operating and nonoperating positions, said mechanism comprising a saddle having a cross member extending horizontally between the boat and the leg of the motor and arms extending rearwardly along opposite sides of the leg, a cylinder secured to each arm and arranged parallel therewith, a piston in each cylinder, a rod in each cylinder attached to the piston and extending from the forward end of the cylinder, means for pivotally attaching one end of each rod to the boat, a cylinder of compressed gas, a conduit connecting said gas cylinder with said first mentioned cylinders, a valve in said conduit for controlling the flow of gas from said gas cylinder to said first mentioned cylinders, a releasable means including an element operated in response to the movement of one of said piston rods for locking said one piston rod in and releasing it from its extended position, and a rod attached to one of said first mentioned cylinders for holding said saddle in its operating position.

4. A mechanism for raising and lowering a boat motor having a frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the rear of a boat including a pivot forming a horizontal axis on which the leg tilts between operating and nonoperating positions, comprising a frame having a cross member extending horizontally between the boat and the leg of the motor and arms extending rearwardly along the opposite sides of the leg, a cylinder secured to each arm and arranged parallel therewith, a piston in each cylinder, a rod in each cylinder attached to the piston and extending from the forward end of the cylinder, means for pivotally attaching one end of each rod to the boat, a releasable means including an element operated in response to the movement of one of said piston rods for locking said one piston rod in and releasing it from its extended position, a cylinder of compressed gas, a conduit connecting said gas cylinder with said first mentioned cylinders, a valve in said conduit for controlling the fiow of gas from said gas cylinder to said first mentioned cylinders, and an exhaust valve in said conduit between said control valve and said first mentioned cylinders.

5. A mechanism for raising and lowering a boat motor having a frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the rear of a boat including a pivot forming a horizontal axis on which the leg tilts between operating and nonoperating positions, comprising a U-shaped frame having a cross member extending horizontally and arms extending rearward-1y along opposite sides of the leg, cylinder, piston and rod assemblies having one end attached to said U-shaped frame on opposite sides thereof and the other end connected to the boat, a source of compressed gas, a conduit connecting said source with said cylinders, a valve in said conduit for controlling the flow of gas from said source to said cylinders, an exhaust valve in said conduit between said control valve and said cylinders, a releasable means including an element operated in response to the movement of one of said piston rods for locking said one piston rod in its extended position and the U-shaped frame in its motor lifted position and for releasing said rod and frame from said position, and a rod connected to said U-shaped frame for holding said frame in its operating position.

6. A mechanism for raising and lowering a boat motor having a frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the rear of a boat including a pivot forming a horizontal axis on which the leg tilts between operating and nonoperating positions, comprising a frame having a cross member extending horizontally between the boat and the leg of the motor, cylinder, piston and rod assemblies having one end attached to said second mentioned frame on opposite sides thereof and the other end connected to the boat, a releasable means including an element operated in response to the movement of one of said piston rods for locking said one piston rod in and releasing it from its extended position, a source of compressed gas, a conduit connecting said source with said cylinders, a valve in said conduit for controlling the flow of gas from said source to said cylinders, and an exhaust valve in said conduit between said control valve and said cylinders.

7. A mechanism for raising and lowering a boat motor having a'frame, a leg depending from said frame for supporting a propeller, and means for mounting said motor on the rear of a boat including a pivot forming a horizontal axis on which the leg tilts between operating and nonoperating positions, comprising a U-shaped rrame having a cross member extending horizontally between the boat and the leg of the motor and arms extending rearwardly along opposite sides of the leg, a cylinder, piston and rod assembly having one end attached to said U-shaped frame and the other end arranged to be connected to the boat, a source of compressed gas, a conduit connecting said source with said cylinder, and a valve in said conduit remotely positioned with respect to said cylinder and having a means for controlling the flow of gas from said source to said cylinder.

8. A mechanism for raising and lowering a boat motor having a leg and means for pivoting said leg between operating and nonoperating positions, comprising a frame for engaging said leg, a cylinder, piston and rod assembly having one end attached to said frame and the other end arranged to be connected to the boat, a cylinder of compressed gas, a conduit connecting said gas cylinder with said first mentioned cylinder, and a valve in said conduit for controlling the flow of gas from said gas cylinder to said first mentioned cylinder, an exhaust valve in said conduit between said control valve and said first mentioned cylinder, and a releasable means including an element operated in response to the movement of said piston rod for locking said piston rod in its extended position and for releasing said rod from said position.

9. A mechanism for raising and lowering a boat motor having a leg and means for pivoting said leg between operating and nonoperating positions, comprising a frame for engaging said leg, a cylinder, piston and rod assembly having one end attached to said frame and the other end arranged to be connected to the boat, a cylinder of compressed gas, a conduit connecting said gas cylinder with said first mentioned cylinder, and a valve in said conduit remotely positioned with respect to said first mentioned cylinder and having a means for controlling the flow of gas from said gas cylinder to and from said first mentioned cylinder.

10. A mechanism for raising and lowering a boat motor having a leg and means for pivoting said leg between operating and nonoperating positions, comprising a frame for engaging said leg, a cylinder, piston and rod assembly having one end attached to said frame and the other end arranged to be connected to the boat, a source of compressed gas, a conduit connecting said source with said cylinder, and a valve in said conduit remotely positioned with respect to said cylinder and having a means for controlling the flow of gas from said source to and from said cylinder.

11. In a mechanism for raising and lowering a boat motor having a leg and means for pivoting said leg between operating and nonoperating positions: a frame for engaging said leg, a cylinder, piston and rod assembly having one end attached to said frame and the other end arranged to be connected to the boat, a means for locking said piston rod in its extended position including a recess in said rod, a plunger for seating in said recess, a lug for retracting said plunger from said recess as said rod is extended, and means for alternately placing said plunger in its retracted and extended positions for locking and releasing said rod.

References Cited in the file of this patent UNITED STATES PATENTS 1,286,051 Meyers Nov. 26, 1918 2,562,493 Harris July 31, 1951 2,966,876 MacWilliam Jan. 3, 1961 FOREIGN PATENTS 948,854 Germany Sept. 6, 1956