U.S. patent application number 09/920139 was filed with the patent office on 2002-01-17 for hydraulically retractable hydraulic motor.
Invention is credited to Gerlach, C. Richard.
Application Number | 20020006345 09/920139 |
Document ID | / |
Family ID | 24008556 |
Filed Date | 2002-01-17 |
United States Patent
Application |
20020006345 |
Kind Code |
A1 |
Gerlach, C. Richard |
January 17, 2002 |
Hydraulically retractable hydraulic motor
Abstract
A method and apparatus for hydraulically engaging and
disengaging a hydraulic motor comprising a rotor and a stator.
Inventors: |
Gerlach, C. Richard;
(Pleasanton, TX) |
Correspondence
Address: |
FULBRIGHT & JAWORSKI L.L.P.
John M. Mings
Suite 5100
1301 McKinney
Houston
TX
77010-3095
US
|
Family ID: |
24008556 |
Appl. No.: |
09/920139 |
Filed: |
August 1, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09920139 |
Aug 1, 2001 |
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09504988 |
Feb 15, 2000 |
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6312238 |
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Current U.S.
Class: |
418/69 |
Current CPC
Class: |
F04C 14/06 20130101;
F04C 15/0061 20130101; F03C 1/0403 20130101; F16D 11/10 20130101;
F16D 25/086 20130101 |
Class at
Publication: |
418/69 |
International
Class: |
F03C 002/00; F01C
021/00 |
Claims
What is claimed is:
1. A retractable shaft motor assembly comprising: an axially
moveable drive shaft; an actuator rod in communication with the
drive shaft; a hydraulic actuator in communication with the
actuator; and a motor positioned between the drive shaft and the
hydraulic actuator.
2. The apparatus of claim 1 in which the actuator rod is slideably
positioned along an axis of the motor.
3. The apparatus of claim 1 in which the actuator rod is
non-torque-bearing.
4. The apparatus of claim 1 in which the motor is a hydraulic
motor.
5. A hydraulically retractable shaft motor comprising: a motor, the
motor having a longitudinal axis; an axially moveable output shaft,
the output shaft having an interface for selectively engaging an
external rotary load; and an axial hydraulic actuator assembly
connected to the output shaft.
6. The apparatus of claim 5 in which the hydraulic actuator
assembly comprises a cylinder, a piston, and an actuator rod.
7. The apparatus of claim 5 in which the motor is a hydraulic motor
comprising a rotor and a stator; and the hydraulic actuator
assembly comprises a non-torque bearing actuator rod.
8. The apparatus of claim 6 in which the actuator rod is non-torque
bearing.
9. The apparatus of claim 8 in which the actuator rod is rotatably
connected to the piston.
10. The apparatus of claim 8 in which the motor and the output
shaft have longitudinal coacting splines.
11. A method of disengaging a hydraulic motor having a rotor, a
stator, and a longitudinally moveable output shaft in selective
communication with the rotor, comprising: hydraulically and
longitudinally moving the output shaft relative to the rotor
whereby the output shaft disengages from the rotor.
Description
SPECIFICATION
[0001] This application is a continuation of U.S. Pat. App. Serial
No. 09/504,988.
BACKGROUND OF THE INVENTION
[0002] The present invention is a method and apparatus for
hydraulically disengaging an output shaft of a hydraulic motor. In
particular, the hydraulic motor includes a longitudinal movable
output shaft which may be moved hydraulically for allowing the
driven mechanism to rotate without interference from the hydraulic
motor.
[0003] In hydraulic equipment, and especially mobile hydraulic
equipment, it is often necessary and/or desirable to disengage the
hydraulic motor from the mechanism it is driving so as to free
wheel the mechanism. An example of this is a hydraulic motor which
is connected to the wheels of a mining machine and used to propel
the mining machine. When it becomes necessary to tow the mining
machine the hydraulic motor must be disengaged from the drive train
so the machine will roll freely. Another example is a scissor-lift
used to load and unload aircraft. It is typically driven with a
hydraulic motor connected to its drive train. When this vehicle
requires towing, it is again necessary to disengage the motor from
the drive train. Another example is a knuckle-boom loader which is
used in the harvesting of timber. When it is in the woods, it is
propelled by a hydraulic motor connected to its drive train. When
it is transported to another job site, the hydraulic motor must be
disconnected to allow the knuckle-boom loader to be towed.
[0004] Yet still another example is when a hydraulic motor is used
to drive a winch. It is often necessary to disengage the motor in
order to free wheel cable off the winch. Disengaging the hydraulic
motor in the above examples is often accomplished by unbolting and
physically removing the motor, building an elaborate slide which
will slide the motor out of engagement, or using an expensive
clutch between the motor and the drive train which can disengage
the motor. Such disengagement may also be accomplished by hand, as
set forth in U.S. Pat. No. 5,261,801. However, the art lacks a
means of hydraulically engaging and disengaging a hydraulic
motor.
SUMMARY OF THE INVENTION
[0005] An object of the present invention is to provide an
automated means of engaging and disengaging a hydraulic motor from
an external rotary load. Another object of the invention is to
provide a means of easily retrofitting prior art hydraulic motors
with automated means of engaging and disengaging the motor. Another
object of the present invention is to provide a non-torque bearing
hydraulic actuator.
[0006] There is provided a retractable shaft motor assembly
comprising an axially moveable drive shaft, a retractable rod in
communication with the drive shaft, an actuator in communication
with the retractable rod, and a motor positioned between the drive
shaft and the actuator. The actuator rod may be fixedly connected
to the drive shaft. The actuator rod may be rotatably connected to
the actuator. The actuator rod may be slidably positioned along an
axis of the motor. The retractable actuator rod may be
non-torque-bearing. The motor may be a hydraulic motor.
[0007] There is also provided a hydraulically retractable shaft
motor comprising a motor, the motor having a longitudinal axis, an
axially moveable output shaft, the output shaft having an interface
for selectively engaging the motor, and an axial hydraulic actuator
assembly connected to the output shaft. The hydraulic actuator
assembly may comprise a cylinder, a piston, and an actuator rod.
The motor may be a hydraulic motor comprising a rotor and a stator,
and the hydraulic actuator assembly may comprise a non-torque
bearing actuator rod. The actuator rod may be non-torque bearing.
The actuator rod may be rotatably connected to the piston. The
motor and the output shaft may have longitudinal coacting
splines.
[0008] There is also provided a method of disengaging a hydraulic
motor having a rotor, a stator, and a longitudinally moveable
output shaft in selective communication with an external rotary
load, comprising hydraulically and longitudinally moving the output
shaft relative to the rotor whereby the output shaft disengages
from the external load.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a cross-sectional view of a disengaged,
hydraulically-engageable hydraulic motor exemplary of the present
invention.
[0010] FIG. 2 is a cross-sectional view of an engaged,
hydraulically-engageable hydraulic motor exemplary of the present
invention.
[0011] FIG. 3 is a cross-sectional view of an alterative embodiment
of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] FIG. 1 depicts a cross-sectional view of a disengaged
hydraulically engageable hydraulic motor 10 exemplary of the
present invention. The hydraulic motor 10 comprises a rotor 12 and
stator 14. Output shaft 16 exhibits a dog-face clutch 17 axially
and rotatably attached to retractable spline portion 20. Motor
shaft 22 is integral with rotor 12 and exhibits splines 24. Splines
24 slideably coact with splines 26 of output shaft 16. Actuator rod
28 is fixed to output shaft 16 by bolt 30 and, whereby actuator rod
28 rotates with output shaft 16.
[0013] Actuator rod 28, and in turn output shaft 16, are moved
axially by actuator piston assembly 31. Actuator piston assembly 31
comprises actuator piston 32, which rotatably communicates with
actuator rod 28 via thrust flange assembly 34. Thrust flange
assembly 34 comprises thrust flange 36, thrust bearings 38, thrust
washer 40, and snap ring 42. Thrust flange assembly 34 enables
actuator rod 28 to rotate relative to piston 32. Thrust flange
assembly 34 is connected to the actuator rod 28 by bolt 33.
[0014] Actuator piston assembly 31 is driven axially within
cylinder 44 by alternating hydraulic fluid pressures through
hydraulic fluid passageways 46 and 48. Hydraulic fluid passageway
46 injects hydraulic fluid into and bleeds hydraulic fluid from
chamber 50, and hydraulic fluid passageway 48 injects hydraulic
fluid into and bleeds hydraulic fluid from chamber 52. Actuator
piston seals 54 prevent communication of hydraulic fluid between
chamber 50 and chamber 52.
[0015] Actuator rod main rotary seal 56 in seal plate 58 prevents
communication of hydraulic fluid from the front hydraulic cavity 52
to the motor case 60. Actuator rod seal 61 prevents leakage of case
fluid.
[0016] Actuator piston assembly 31 and actuator rod 28 selectively
drive output shaft 16 and attached dog-face clutch 17 and dog teeth
18 in and out of engagement with dog-face clutch teeth 72 of load
shaft 70. Once engaged, motor shaft 22 rotates load shaft 70.
Actuator rod 28 is not imparted the full torque of the motor shaft
22, because the output shaft 16 communicates directly with the
motor shaft 22, and because actuator rod 28 rotates relative to the
actuator piston assembly 31.
[0017] To engage hydraulic motor 10 of the present invention,
hydraulic fluid is injected through hydraulic fluid passageway 46
into chamber 50, while simultaneously venting any hydraulic fluid
in chamber 52 through passageway 48, whereby shaft 16 forces
dog-face clutch 17 into engagement with dog-face clutch 70. To
disengage the hydraulic motor 10, the foregoing hydraulic fluid
flow is reversed.
[0018] FIG. 2 depicts the motor of FIG. 1 in an engaged position,
with splines 24 and 26 coacting with each other, and dog-face
clutch teeth 18 engaged with dog-face clutch teeth 72.
[0019] FIG. 3 depicts an alternative embodiment of the present
invention, in which 25 output shaft 16 comprises an engagement
mechanism 64 exhibiting external splines 66. Engaged position 68 is
shown in shadow. External load shaft 74 exhibits internal splines
76 which are selectively engageable with splines 66. The engaged
position of splines 66 with splines 76 is shown in shadow by
position 68.
[0020] The foregoing are merely examples of the invention. One of
ordinary skill in the art will appreciate that several embodiments
of the invention may be devised within the scope of the claims.
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