US 4,726,257 A · Balanced steerable transmission

Abstract

This power transmission has a steerable sleeve mounted for pivoting about an axis coaxial with the output shaft of the transmission. The steerable sleeve can be pivoted in either direction with equal torque regardless of rotation of the output shaft. The output shaft has two output gears. Two gear drive trains that are substantially the same interconnect the input shaft to the two output gears of the transmission. In an exemplary embodiment the first drive train includes a ring gear driven by the input shaft, at least one planetary gear, and a sun gear which is the first output gear on the output shaft. The second drive train has a ring gear driven in the opposite sense of rotation from the first ring gear, at least one planetary gear and a transfer gear face substantially the same as the first output gear. The transfer gear is connected to a reversing gear assembly on the steerable sleeve so that torque is applied to the second output gear on the shaft. The two planetary gears are interconnected by a spider which is free to pivot and compensate for motion of the steerable sleeve. The spider assures that advance of one planetary gear drive equals recession of the other planetary gear drive. Since the two drive trains are equivalent and contra-rotating, torques are balanced.

Drawings

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Drawings

Claims31

Dependent claims

A steerable power transmission comprising:

a stationary housing;
a rotatable input shaft in the housing;
a rotatable output shaft in the housing;
a first output gear on the output shaft;
a second output gear on the output shaft;
a steerable sleeve pivotable relative to the housing about an axis coaxial with the output shaft and pivotable relative to both output gears;
a first drive train comprising a first gear drive coupling the input shaft to the first output gear;
a second drive train comprising a second gear drive substantially similar to the first gear drive, the second drive train comprising a transfer tube rotatable relative to the steerable sleeve coupling the input shaft to the second output gear;
and
a spider interconnecting portions of the first and second drive trains and mounted for advancing one drive train an amount equal to recession to the other drive train in coordination with pivoting of said steerable sleeve.

7 more elements

A balanced steerable power transmission comprising:

a stationary housing;
an input shaft entering the housing on an input axis;
an output shaft entering the housing on an output axis;
a steerable sleeve mounted on the housing for pivoting about an axis coaxial with the output axis;
a first output gear on the output shaft;
a first drive train coupling the input shaft to the first output gear;
a second output gear on the output shaft;
reversing gear means mounted on the steerable sleeve for rotation relative to the sleeve about an axis perpendicular to the output axis, the reversing gear means being in engagement with the second output gear on the output shaft;
a second drive train substantially the same as the first drive train coupling the input shaft to the reversing gear means and including transfer gear means coaxial with the output shaft in engagement with the reversing gear means, the transfer gear means including a gear face substantially the same as the first output gear;
and
means interconnecting the first and second drive trains for processing in coordination with pivoting of the steerable yoke so that substantially no net torque is applied to the steerable sleeve by the drive trains regardless of the direction of pivoting of the steerable sleeve.

8 more elements

A balanced steerable power transmission comprising:

a stationary housing;
first and second ring gears in the housing coaxial with the output shaft;
means connected to the input shaft for driving the ring gears in opposite directions;
a rotatable input shaft entering the housing;
a rotatable output shaft entering the housing;
a first output gear on the output shaft;
a second output gear on the output shaft;
a steerable sleeve entering the housing coaxial with the output shaft and pivotable relative to the housing;
a spider mounted in the housing coaxial with the output shaft and pivotable relative to the housing;
first gear means mounted on the spider for precession therewith for transmitting power from the first ring gear to the first output gear;
transfer gear means coaxial with the output shaft and having a gear face substantially the same as the first output gear;
second gear means mounted on the spider for precession therewith for transmitting power from the second ring gear to the transfer gear means;
and
reversing means on the steerable sleeve connected between the transfer gear means and the second output gear for transmitting power from the transfer gear means to the second output gear with an opposite sense of rotation from the transfer gear means.

11 more elements

A steerable transmission comprising:

a stationary housing;
a rotatable input shaft entering the housing;
a rotatable output shaft entering the housing;
a first output gear secured to the output shaft;
a first ring gear coaxial with the first output gear;
at least one planetary gear interconnecting the first ring gear and the first output gear;
a transfer tube coaxial with the output shaft and including a transfer sun gear face similar to the face on the first output gear;
a second ring gear coaxial with the transfer sun gear face;
at least one planetary gear interconnecting the second ring gear and the transfer sun gear face;
an input spur gear on the input shaft for driving the first ring gear;
an input reversing spur gear engaging the input spur gear and the second gear for driving the second ring gear in the opposite sense of rotation from the first ring gear;
a spider mounted in the housing for pivoting coaxial with the output shaft;
means for mounting the planetary gears on the spider for pivoting therewith and for rotation around the planetary gear axes;
a transfer gear face on the transfer tube;
a second output gear secured to the output shaft having a gear face substantially the same as the transfer gear face;
at least one reversing gear means interconnecting the transfer gear face and the second output gear for driving the second output gear in the same sense of rotation as the first output gear;
a steerable sleeve entering the housing and pivotable coaxial with the output shaft;
and
means for mounting the reversing gear means on the steerable sleeve for pivoting therewith and for rotation around the reversing gear axes.

16 more elements

A steerable transmission comprising:

a stationary housing;
a rotatable input shaft entering the housing;
a rotatable output shaft entering the housing;
a first output bevel gear secured to the output shaft;
a second output bevel gear secured to the output shaft;
a first ring gear coaxial with the first output gear and including a bevel gear face;
at least one idler bevel gear interconnecting the bevel gear face on the first ring gear and the first output bevel gear;
a transfer tube coaxial with the output shaft and including a transfer bevel gear face substantially the same as the face on the first output gear;
a second ring gear coaxial with the transfer sun gear face and including a bevel gear face;
at least one idler bevel gear interconnecting the bevel gear face on the second ring gear and the transfer bevel gear face;
means connected to the input shaft for driving the first and second ring gears with opposite sense of rotation;
a spider mounted in the housing for pivoting coaxial with the output shaft;
means for mounting the idler bevel gears on the spider for pivoting therewith and for rotation around the idler bevel gear axes;
a transfer gear face on the transfer tube;
at least one reversing gear means interconnecting the transfer gear face and the second output gear for driving the second output gear in the same sense of rotation as the first output gear;
a steerable sleeve entering the housing and pivotable coaxial with the output shaft;
and
means for mounting the reversing gear means on the steerable sleeve for pivoting therewith and for rotation around the reversing gear axes.

15 more elements

Dependencies are inferred from the claim text.

Description6,063 words

Summary553 words

#This invention concerns a power transmission having a steerable sleeve independent of the input and output drives. The transmission has two contra-rotating drive trains between the input and output shafts, which permits steering the sleeve in either direction with equal torque.

#This invention comprises an improvement over balanced steerable power transmissions disclosed in my U.S. Pat. Nos. 3,750,616 and 3,851,614. The subject matter of the aforementioned patents and applications is hereby incorporated by reference.

#In the steerable transmissions of the above-identified patents there are input and output shafts with the output shaft mounted in a housing which is steerable. This permits the direction of the output shaft to be changed independently of the direction of rotation of the input shaft. Such an arrangement can be used, for example, for steering a boat, thereby gaining benefits of both an inboard and an outboard arrangement. These transmissions can be somewhat cumbersome and have appreciable drag since a large housing is rotated.

Brief description of the drawings9 figures

#These and other features and advantages of the present invention will be appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

#FIG. 1 illustrates in slightly schematic perspective cutaway a balanced steerable transmission constructed according to principles of this invention;

#FIG. 2 is a schematic longitudinal cross section through the transmission;

Detailed description5,341 words

#One embodiment of the balanced steerable power transmission is illustrated somewhat schematically in the longitudinal cross section of FIG. 2, and in a perspective view with portions of the housing and internal mechanisms cut away in FIG. 1. As illustrated in these views, the housing of the transmission comprises a main casing 11 closed at the bottom by a lower cover 12 and at the top by an upper cover 13. An input shaft 14 enters one side of the main casing 11. An output shaft 16 extends through the lower cover 12 coaxial with the housing of the power transmission which is essentially circular in transverse cross section. The output axis is perpendicular to the input axis.

#As used herein, the designations of top and bottom of the transmission are used with respect to the drawings in FIGS. 1 and 2. This is done for convenience in the description and there is no relation to the orientation of the transmission in service. In practice the transmission can be oriented in any direction.

#Also for convenience in description, one of the shafts 14 is referred to as the input shaft and the other shaft 16 is called the output shaft. These roles can be reversed with power applied to the "output" shaft and a driven member connected to the "input" shaft. Thus, within this specification and accompanying claims, "input," "output," "upper," "lower," and the like are employed for clarifying the members referred to and are not words of limitation. In general, "input" could be read "output" and vice versa.

Facts

Application

06/843,013Filed 24 Mar 1986 · continuation in part

Priority

27 May 1980

Granted

23 Feb 1988

Term ended

23 Feb 2005

Estimated · how

Pre-1995 term; greater of 17 years from grant or 20 years from filing when eligible. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification3 codes

F16H 1/006
Toothed gearings for conveying rotary motion: the driving and driven axes being designed to assume variable positions relative to one another…
F16H 37/08
With a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts: with differential gearing
F16H
Gearing

Balanced steerable transmission

Life of this patent

Balanced steerable transmission

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims31

Description6,063 words

Drawings

Classification3 codes

Life of this patent

Description6,063 words