US1326282A - Dorr miller - Google Patents

Description

D. MILLER.

STEERiNG GEAR.

APPLICATION man 0m28.191s.

Patented Dec. 30, 1919.

m RJ MM srarns f Donn MILLER, or CHICAGO; ILLINOIS.

STEERING-GEAR.'

Application sied December 2s, 191e. serial No.

To all whom z'mag/ concern:

Be it known that l, Dorm MILLER, a citizen of the United States, residing at Chicago, county of Cook, State of Illinois, have invented a certain new and`useful Improvement in Steering-Gears, and declare the following' to be a full, clear, and exact descriptionof theI same, such as'will enable others skilled in the art to whichr yit pertains to make and use the same,reference being had to the accompanying drawings, which form a part of this specification. 4

My invention has for its object to produce a simple, powerful mechanism which will make it-` possible to steer with a minimum expenditure of effort and obtain substantially complete locking against backward impacts'transmitted from the wheels, whereby a motor carwill be completely .responsive` to the slightest steering suggestion of the driver and for all practical purposes wholly unresponsive to tendencies of `the wheels, because ofthe condition of the road, or for other reasons, to vary the direction of travel. v

` ,A steering gear having the aforesaid characteristics lends itself very advantageously to what is known as quick steering"I and therefore, viewed ,in one of itsaspects, my invention may be said to have for itsgoebjectto produce a simple and efiicient quick The various Ifeaturesof novelty whereby my` invention is characterized will hereinafter be pointed out with .particularity in the claims', but, for a fullunderstanding of my invention and of its objects and advantages, reference may be hadto the following detailed description taken in connection with the accompanying drawing, wherein: l i

Figure l is a view partly-.inV side elevation and partly in section through a steerin mechanism arranged inaccordance with a preferred form of my invention; e e

F ig. 2 is a section on a somewhat larger scale taken approximately online 2%-2 of Fig. l, looking in the direction of the arrows, the housing being omitted and the ends of the rock shaft broken away '5 Fig. 3 is a sidev elevation of the driving segment;

Specification of Letters Patent;

Patented Dec. so, 1919. 139,280. l

Fig. `4 is a side elevation ofthe driven member including the rock shaft; and

Fig. 5 is a `side elevation of thestationarycam plate between which and the segment the driven member is locatedf Referring to the drawing, `l represents a steering post at the lower end of which is a suitable casing or housing, 2, into which extends the lower end of a Steering shaft, 3. All these parts may take any usual or preferred forms. Extending. transversely through the casing is a rock shaft, 4,- whose axis is at right angles to the axis of the steering shaft. Y member 5,

and independent ofthe latter and el' the rock shaft` are disks or plates, the rock shaft. The member 6 is rotatable relatively to the casing while the `member 7 is fixed to the. casing in any suitablewa'y as, for example, by devices, 8. The disk 5 has two openings,4 9, extending through the saine, these openings being any desired distance apart. In the arrangement shown, the holes 9 are placed at diametrically opposed points. The faces of the members 6 and 7 which lie contiguous to the member 5 are providedV with cam tracks, l0 and l1, which are similar to each other, each rising gradually and at a uniform rate inboth directions from a low point to a high point or points. The a1igular .distance "fromV the low pointof each cam track to `onecf the high points may vary from asmalljangle to an angle of 180 degrees as illustrated; the two high points of each cani track being superposed upon each other ,in the arrangement shown so that each track is inl substance an annular undulating4 surface having one high point and one low point. The cam surfaces are so disposed that what mayv betermed the center line of each will be at the samedistance from theaxis ofthe rock shaft a's'the centers of the holes 9 in the `member. Extending through the holes 9 are devices, preferably in the forin'ofballs, 12,'as` illustrated, which are required to oscillate with the rock shaft but are free to move independently of the latter in either. direction' parallel with the axis of the rock shaft.

The parts are so proportioned thatv when On opposite sides ofJ the.

6 im@ 75; the center of each of which is at the axis ofV a fastening device or they are assembled as shown in Figs. 1 and 2, with the high point, 14, of the cam 10 directly opposite the high point 15 on the cam 11, the opposed cam surfaces in the vicinity of the'balls will be just far enough apart to permit each ball to engage with both cam surfaces; while in any other relative angular position of the two members 6 and 7` there will be found two diametrically opposed points which are spaced apart a distance equal to the diameter of the balls.

The result of this construction is that if the member 6 is turned from the position indicated in Figs. 1 and 2, whether toward the right or toward the left, the opposed cam surfaces in the initial position of one of the balls approach each other so that the only thing it is possible for this ball to do is to travel ahead and this it will do at just the proper rate to remain at all times in contact with both cams. As the ball travels ahead it moves gradually away from the high point of the cam 11 and toward the low point so that its rate of travel need be only half what it would be if it engaged with a. plain surface instead of with the cam 11 and were pushed ahead along this plain surface by the cam 10. Therefore the ball, which happens to be the driven ball, and the member 5 which must move with it, will be moved about the axis of the rock shaft at just half the speed of the member 6. It will be seen that when one of the balls is driven ahead by the cam 10, the other ball is carried ahead with the member 5 so as always to remain in contact with both of the cam surfaces and the latter ball is therefore always ready to act as the driving member for the rock shaft upon reversing the direction of rotation of the member 6. It will thus be seen that in any relative angular positions of the members 6 and 7 one of the balls is always ready to take hold instantly and drive the rock shaft when the member 6 is turned in one direction while the other ball is always ready to act as the driving member for the rock shaft when the member 6 is turned in the other direction. Consequently there is never any back lash or lost motion but, since the member 6 is turned in either direction, the member 5 on the rock shaft begins to move in the same direction but at only one-half the speed. v

TWhile the rock shaft responds instantly to any small turning force applied to the driving member 6, because of the small angle of the cam surfaces, any turning force eX- erted directly upon the rock shaft has practically no effect on the driving member 6 which acts in substance like a wedge of small angle interposed between' the balls and the sides of the casing and therefore acts as a lock for the rock shaft instead of permitting itself to be driven backward by 'the latter.

Lezama ln order to drive the member 6 from the steering shaft, it is provided with a gear segment, 16, meshing with a pinion, 17, on the lower end of the steering shaft. From the foregoing description it will be seen that when the steering wheel is turned in either direction, the rock shaft is instantly set in motion. When the steering wheel comes to rest the, rock shaft does the same and, furthermore, is locked against movement in either direction until the steering wheel is again manipulated, so that road shocks will not be carried back to the steering wheel.

TWhile the cams may be made to have point contact with the balls, l prefer to make them in the form of grooves curved on the same radius as the balls so as to produce a line contact instead of a point contact.

I prefer, also, to place between the driving member 6 and the adjacent wall of the casing a suitable wearing plate, 18, preferably of cast iron.

lt will be seen that the present invention embodies the same principle of differentiation as that disclosed in my prior application for differential gearing, filed March 11, 1915, Serial No. 13,616, only a single set of cams and engaging elements being required in the present instance because the driven shaft is intended to oseillate, while in my aforesaid application a plurality of sets of cams and cam-engaging devices are required for the purpose of permitting one set to come in operation after the other and thus make it possible to secure rotation as distinguished from mere oscillation. In my aforesaid application the member corresponding to the rock shaft in the present case is the driving member, but the reason that the rock shaft is not an effective driving member is that the angle of the cams is made smaller than the angle which would be chosen for a differential gear, and this results in such a great leverage in favor of the member 6 that enlya 4slight force, which may be regarded as negligible, need be applied to the steering wheel to hold it against back action due to any tendency of the rock shaft to act as a driving member.

W'hile l have illustrated and described with particnlarity only a single preferred form of my invention, l do not desire to be limited to the exact structural details thus illustrated and described; but intend to cover all forms and arrangements which come within the terms employed in the definitions of my invention constituting the appended claims.

l claim:

1. 1n combination, three members located adjacent to each other and movable relatively to each other about a common axis, the two outer members each having a cam surface facing the other cam surface and arranged in the arc of a circle having its center at said axis, eachof said surfaces rising gradually from a low point to two high points, two balls carried by and movable with the intermediate member about said axis and movable `relatively to the intermediate member in the direction of said axis, said balls being located between said cam surfaces and being spaced apart a distance equal to the distance from the low point on one of the cam surfaces to one of the high points on the sameV cam surface, and means for actuating one of the outer members.`

2. In combination, a rocking device, two members arranged on opposite sides of said rocking device and one of the members being movable about the pivotal axis of the rocking device, each of said members having on the face directed toward the other a cam surface rising gradually in opposite directions from a low point, said cam surfaces being similar to each other and similarly arranged, and two similar separated elements carried by said rocking device and movable therewith in the direction of the length of said cam surfaces and movable relatively to said rocking device in directions parallel with said axis, and means for actuating the aforesaid movable member.

3. In combination, a rock shaft, two disks surrounding the rock shaft and movable relatively thereto, said disks each having a cam surface facing the other cam surface and arranged in the arc of a circle having its center at the axis of the rock shaft, Veach of said surfaces rising gradually in opposite directions from a low point, a part connected with the rock shaft lying between said disks, two elements carried by said part and each engaging with both of Vsaid cam surfaces, said elements being movable angularly with the rock shaft and being movable relatively to the rock shaft in directionsparallel to the aforesaid axis, 'and means for actuating one of said disks.

4. In combination, a member movable angularly about an axis, said member having a cam surface arranged in the arc of a circle about said axis and rising gradually in opposite directions from a low point relatively to a plane extending at right angles to said axis, a stationary member -spaced apart from the aforesaid member and having thereon a cam surface similar to and facing the aforesaidV cam surface, a device arranged between said members and adapted to be moved angularly about saidaxis, and two cam-engaging elements carried by said device and each engaging both of said `cam surfaces, said cam-engaging elements being movable about said axis with said device and being movable relatively to said device in directions parallel with said axis.

5. In a steering shaft extending through said casing, two

ear a casing a rock members arranged within the casing about the rock shaft, one of the members being fixed to the casing andthe other being movable angularly about the axis of the rock shaft, each of said members having a cam surface facing the other cam surface and arranged in the arc of a circle having its center at said axis, each cam surface rising gradually in opposite directions from a low` point, a device fixed to the rock shaft and lying between said members, two elements carried by and movable with said device about said axis and movable relatively to said device in directions parallel with said axis, a steering shaft, and a driving connection between said steering shaft and the aforesaid rotatable member.

G. In a steering gear, a casing, a rock shaft extending through the casing, two disks arranged within the casing about said shaft, each of said disks having' a cam sur face facing the other cam surface and arranged in the arc of a circle having its center at the axis of the rock shaft, each of said surfaces rising gradually in opposite directions from a low point, a part extend` ing radially from said shaft between said disks, two elements carried by and movable with said part about said axis and movable relatively to said part in directions parallel with said axis, one of said disks being fixed to the casing, and means for oscillat-` ing the other disk.

7..In combination, a driving member, thereto, said stationary ing member being a stationary member, journaled adjacent member and drivprovided with opposed cam surfaces, a drivfen member suitably journaled and coupling members carried thereby and interposed between the cam surfaces and said cam surfaces being formed to coact with the coupling members whereby motion transmitted by the driving member will effect movement of the driven member in either direction and the parts will lock under pressure from the driven member to prevent motion being transmitted thereby to the driving member.

8. In combination, a stationary member, a driving member journaled adjacent thereto, said stationary member and driving member being provided with opposed cam surfaces, a driven member suitably journaled and coupling members carried thereby and interposed between the cam surfaces and said cams being formed to coact with the coupling members whereby motion transmitted by the driving member will effect the movement of the driven member at one half the speed of the former in either direction and to effect the locking of the parts Linder pressure from the driven member to prevent motion being transmitted from the driven member to the driving member, substantiallyas describe 9. In a steering gear mechanism, a driv- With-to be operative to lock under pressure ing` member and a driven member and Cou- `from the driven member to prevent motion plng means therebetween adapted t0 trzinsbein transmitted thereby te the driving 10 mit motion from the driving member to the mem el'. 5 driven member in both directions, said ceu- In testimony whereof, I sign this specifipling means comprising coupling elements cation. and cam members adapted to co-act there- DORR MILLER.

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