U.S. patent number 3,901,104 [Application Number 05/367,707] was granted by the patent office on 1975-08-26 for transmission for concrete mixers.
Invention is credited to Royal W. Sims.
United States Patent |
3,901,104 |
Sims |
August 26, 1975 |
Transmission for concrete mixers
Abstract
Between the motor and the bowl is a transmission and speed
control shifter. The shifter is a two position shifter in which the
bowl can be driven at either high or low speed depending upon
charging, discharging and transit conditions. The transmission
consists of three stages each comprised of a planetary gear system.
The shifter in one position utilizes only a portion of the first
stage and then transmits further power through the entirety of the
second and third stages. In a second position the shifter utilizes
the entirety of the planetary gear systems of the first, second and
third stages to achieve lower speed mix rate of the bowl. The two
advantages sought and obtained are that presently installed and
used transmission systems can be modified to secure two speed
control and the additional transmission elements are all of
standard size and construction.
Inventors: |
Sims; Royal W. (Salt Lake City,
UT) |
Family
ID: |
23448280 |
Appl.
No.: |
05/367,707 |
Filed: |
June 7, 1973 |
Current U.S.
Class: |
475/279; 74/330;
366/606; 366/60; 475/290 |
Current CPC
Class: |
F16H
3/64 (20130101); F16H 61/0293 (20130101); B28C
5/421 (20130101); Y10S 366/606 (20130101); F16H
2716/02 (20130101); Y10T 74/19228 (20150115) |
Current International
Class: |
F16H
3/44 (20060101); F16H 3/64 (20060101); F16H
61/02 (20060101); B28C 5/42 (20060101); B28C
5/00 (20060101); F16h 057/10 (); F16h 003/08 ();
B28c 005/18 () |
Field of
Search: |
;74/769,768,330
;259/177R,177A |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Scott; Samuel
Assistant Examiner: Lall; P. S.
Claims
What I claim is:
1. An improved transmission for concrete mixers comprising a
shifter mechanism having two independently movable and relatively
laterally displaceable first and second drive members, said first
drive member being selectively movably into engagement with a sun
gear of the first of three intermittently engageable planetary gear
assemblies, said second and third planetary gear assemblies being
connected serially together and to a preselected portion of said
first planetary gear system to effect a drivable connection between
a prime mover and a mixing bowl, said second independently movable
drive member being selectively engageable with a second portion of
said first planetary gear assembly when said first drive member is
disengaged to provide a second drive connection effecting a
different speed between said prime mover and bowl and consisting of
a gear member which forms a direct drive with a different portion
of said first planetary gear assembly than said first drive and
bypassing the sun and planetary gear portion of said first
planetary assembly but utilizing the interfaced second and third
planetary gear assemblies.
2. The improved transmission in accordance with claim 1 wherein the
planetary gear arrangements are disposed in series and are
selectively coupled to effect, in accordance with the gear train, a
selected bowl speed control.
3. The improved transmission in accordance with claim 1 including
operating means which are splined together to provide co-rotating
first and second gear means selectively engageable with a
predetermined portion of the adjacent planetary gear of the first
of three in-series planetary gear systems.
4. The improved transmission in accordance with claim 1 wherein the
first, second and third stage planetary gears are connected in
series and means for acting only through a portion of the first
stage, and means for acting through the entirety of said first
stage whereby the output of said first stage to the combination of
the successively connected second and third stages determine the
bowl speed.
5. The improved transmission in accordance with claim 1 wherein
each of the sun, planetary and ring gears of the three stages is of
standard size and construction.
6. The improved transmission in accordance with claim 1 including
mechanically operable means for laterally shifting on spline
connections, a first and second gear operator which determines the
operative portion of the first planetary gear stage operated
thereby.
7. A process for transmitting rotational energy to a mixing bowl at
one of two preselected speeds comprising the steps of selectively
engaging independently movable and relatively displaceable first
and second drive gear members of a first stage planetary gear
system, coupling said first stage with a combination of in-series
second and third stage planetary gears and connecting the output of
said third stage to a bowl for effectively driving said bowl at a
predetermined speed.
8. The process in accordance with claim 7 including the step of
mechanically shifting relatively to each other one of two gear
operators to effectively determine the rate of bowl speed.
9. The process in accordance with claim 7 wherein said first stage
planetary gear includes sun, planetary and ring gear portions which
are predeterminately operated and transmitting force from said
first stage to successive second stage and third stage planetary
gear systems, wherein that portion of said first stage is operated
to effectively determine bowl speed.
Description
BACKGROUND OF THE INVENTION
It is advisable to provide the user of a self-propelled transit
concrete mixer with a two speed transmission system since the bowl
should be rotated rapidly during the period in which the bowl is
charged with concrete mixture ingredients and should again be
rotated rapidly during the time of discharge.
During transit, however, it is only necessary that the bowl turn
over slowly, just sufficiently to prevent setting up of the
interior contents of the bowl. In fact, the problem of the art is
how to achieve a sufficiently low rate of rotation of the bowl so
that it is not "overmixed." If, during transit, the bowl should
rotate an excessive amount the bowl wears excessively and the
overmixed aggregate (or mixture) is less fit for its intended
purpose and is therefore rejectable. What is needed, is a new and
improved transmission, preferably one which can be made of standard
parts and utilizing readily available planetary gear components and
which can be produced from an existing transmission which does not
have the advantages of the present invention. In other words,
existing self-propelled concrete mixtures which do not have the
features of the present invention can be readily modified by
incorporating conventional or readily available components which
will basically alter the transmission to incorporate the advantages
of a two speed transmission drive between the motor and the
bowl.
OBJECTS OF THE INVENTION
It is a principal object of the present invention to provide a
transmission consisting of first, second and third stages each
comprising planetary gear members which in combination are capable
of driving a bowl at two distinct speeds; a fast speed during
loading and unloading, and a slow speed during transit.
A second object of the present invention is to provide a new and
improved operator mechanism which is manually controlled and
includes two drive members one of which utilizes only a portion of
the first stage of a three stage planetary gear system and thereby
achieves a fast rate of bowl rotation and a second operator
mechanism which utilizes the entirety of the first, second and
third planetary gear systems to achieve a slower rotation of the
bowl during transit.
A further object of the present invention is to utilize a
transmission system consisting of uniform components making up a
planetary gear system wherein a first stage planetary gear system
is interfaced with a second planetary gear system which in turn is
interfaced with a planetary gear system of a third stage. These
three stages are interconnected in either one of two manners,
through the first stage, to effect high and low speeds of rotation
of a bowl.
Other objects and features of the present invention will become
apparent from a consideration of the following description which
proceeds with reference to the accompanying drawings.
DRAWINGS
FIG. 1 is a section view of a transmission system and shifter
mechanism and illustrating the direction of movements of the
shifter mechanism to achieve the selected rate of rotation of the
bowl;
FIGS. 2 and 3 are detailed views illustrating the two positions for
the shifter mechanism the high speed shifter position being
illustrated in FIG. 2 and the low speed being illustrated in FIG.
3; and,
FIG. 4 is an exploded view illustrating the shifter mechanism and
the first, second and third stages of planetary gears which are
interfaced to produce the desired speed of bowl rotation.
SPECIFIC WORKING EXAMPLE OF THE INVENTION
Referring to FIG. 1, a shifter mechanism designated generally by
reference numeral 10 is effective for coupling a motor or engine 12
and a sprocket 14 having a chain connection (not shown) with a
mixer bowl (also not shown).
The shifter mechanism 10 determines the path of force as it moves
through a first stage 16, a second stage 18 and a third stage 20,
each stage consisting of a planetary gear arrangement prior to
ultimate coupling of the engine 12 with the sprocket 14 which is
mounted on drive shaft 22.
The shifter mechanism consists of a shifter plate 24 and shifter
plate 26 the positions of which determine the rate of speed at
which the bowl will rotate. During charging and discharging of the
bowl, the bowl speed should be at a high rate, and during transit
the bowl should rotate at a relatively slow rate so as not to
exceed a predetermined total number of revolutions from the time of
initial charging of the bowl with the concrete mixture ingredients
to the time of discharging such mixture ingredients at the
construction site. The shifter plates 24, 26 have associated
operator rods 30, 32 that determine the coupling of gears through
the first stage 16 (FIG. 4) previously pointed out to be a
planetary gear system. When it is desired to rotate the bowl at a
high speed, the rod 30 associated with plate 24 is moved toward the
right (FIG. 2) and the rod 32, together with plate 26 is moved to
the left (FIG. 2) thus disengaging the splined end 40 of rod 42
from sun gear 44 and engaging the gear member 46 with a sleeve 48
having internal gear teeth 50. The sleeve 48 has a flange 54 which
is connected with a housing 56 and the housing is coupled through
rods 58 to a backing member 60 having internal gear teeth 62 which
mesh with the gear teeth 64 of a transfer rod 66.
The transfer gear rod 66 has gear teeth 68 which operates first the
sun gear 70 of the second stage planetary gear system 18. The
second stage planetary gear system 18 and the third stage planetary
gear system 20 (FIG. 4) are operatively connected together so that
they in turn will operate the shaft 22 and rotate the sprocket
wheel 14 at a relatively high rate of speed as for example 18-20
revolutions per minute. But once the bowl is fully loaded it is
then desired to reduce the rate of mixing of the ingredients within
the bowl and at that point the shifter is again operated and at
this time the rod 30 is moved to the left "A" (FIG. 1) disengaging
the gear 46 from the associated gear teeth 50 of sleeve 48 and the
rod 32 connected with plate 26 is moved toward the right, in the
direction indicated by the letter "B" in FIG. 1, engaging the gear
teeth 40 of rod 42 with sun gear 44 so that the first stage
planetary gear system 16 is connected with the second stage 18
through the backing member 60 thence through transfer gear rod 66
and then to the second and third stage gear mechanisms 18 and
20.
Referring to FIG. 4, the first stage 16 is housed in part by an end
cover 80 which is secured to a casing 82 (FIG. 1) which in turn is
fastened to a chain housing 84.
Each of the first, second and third stages is essentially identical
in the respective gear arrangement other than the arrangement that
the first stage 16 has its initial motor input through gear 40 or
gear 46. Since the various planetary gear arrangements are
identical except as noted; only one will be described it being
understood that the gear parts are for the most part
interchangeable thus making for economy of manufacture and service.
The planetary reducer is standard and is obtained from either Blaw
Konx or Funk.
Referring to the planetary gear arrangement in the first stage 16
(FIG. 4) there is a ring gear 78 with an O-ring seals 92 and 94 one
on each side thereof. The ring gear has meshed therewith three
planetary gears 76 which are supported by associated pivot pins 98,
plates 100 and bearings 102.
As shown in the first stage, each planetary gear is supported on
planetary gear plates 104 and 106 and the planetary gears are
operated by sun gear 44 which is directly drivable by the splined
end 40 of shaft 42.
Force is transmitted from one stage to the next by means of
connecting shafts 66 which couple the first stage 16 to the second
stage 18 and there is a corresponding second shaft 66 connecting
the second stage 18 to the third stage 20 (FIG. 1).
All that is required to change bowl speed is to move the rods 30,
32 in some suitable mechanical manner thus effecting either a
connection from the motor 12 through the motor shaft 110 through
gear 40 (note operative position in FIG. 1) and establishing a slow
bowl rotational speed wherein the shifter elements are disposed as
in FIG. 3; or, the shifter elements are moved to the positions
shown in FIG. 2 wherein 40 is disengaged from the sun gear 44 of
the first stage 16 and instead gear 46 is connected with sleeve 48
which in turn is connected to the casing 56 to effect a bypass of a
portion of the gear arrangement in the first stage 16 and produces
through the second 18 and third 20 stages a faster rate of speed of
the bowl.
The output shaft 22 is mounted on roller bearings 120 and 122
spaced one at each end of the shaft 22 and the sprocket 14 has a
chain connection with the bowl. The sprocket wheel 14 is positioned
by a spring 128 and it can float on the shaft 22 through a splined
connection 129 so as to remain mounted in a proper relative
position in relation to the bowl in spite of its inevitable
shifting movements by means of a spring 128. Details of the
mounting of the sprocket wheel 14 may be obtained by reference to
copending application Ser. No. 348,209 filed Apr. 5, 1973 entitled
"CHAIN TENSIONING DEVICE."
OPERATION
In operation, it is a relatively simple matter to change the bowl
rotational speed by means of the actuating mechanism which
mechanically operates one or the other of the plates 24 or 26,
positioning them either in the position shown in FIG. 2 or FIG.
3.
When it is desired to rotate the bowl at a fast rate of speed which
is the case during charging and discharging, the plates 24 and 26
are positioned as shown in FIG. 2 in which the gear member 46 is
engaged with the coacting gear teeth 50 of sleeve 48 and the motor
12 is then coupled through motor shaft 110 and gear member 46 to
sleeve 48, flange 54, housing 56, rod 58, backing member 60 and
thus through the first stage 16 to the second stage 18 through a
transfer rod 66 which effects the transfer through gear teeth 64
and gear teeth 68. Force then moves through the second and third
stages 18 and 20 in a conventional planetary gear fashion to drive
shaft 22 having splined connection 129 with sprocket wheel 14. The
sprocket 14 has a chain drive connection (not shown) with the bowl
(not shown). When the shifter mechanism is positioned as shown in
FIG. 2 the bowl rotates at a high rate of rotation.
During transit, when the speed of rotation should be relatively
slow, just sufficient to prevent the aggregate from "setting up,"
the bowl rotates, just turning over, in order that the aggregate is
not overmixed and to prevent excessive wear of the interior
components of the bowl. In this case, the shifter mechanism is
changed from the position shown in FIG. 2 to that of FIG. 3 in
which the plate 24 is moved to the left disengaging gear member 46
from sleeve 48 and the plate 26 is moved to the right engaging gear
end 40 with sun gear 44.
In this case, the motor 12 is coupled through the output shaft 110
through gear end 40 with sun gear 44, planetary gears 76 and
backing member 60 to transfer rod 66 thus transferring motive force
from the first stage 16 to the second stage 18. Motive force is
transferred from second stage 18 to third stage 20 as previously
described and thus the entirety of the planetary gear systems of
the first, second and third stages is utilized between the motor 12
and the output shaft 22. The output shaft and splined sprocket 14
are thus rotated at a relatively slow speed in the order of only
one or two revolutions per minute thus preventing the aggregate
from overmixing during transit.
One of the major advantages of the present invention is that it is
so simple to adapt conventional transmissions by simply adding the
shifter mechanism, and adding the first stage support plate and the
additional transfer gear rod. These are relatively easy operations
to perform and the entirety of the gear system is made up of
uniform sized components.
The gear system is lubricated by incorporating the entirety of the
first, second and third stages and shifter mechanism within a
sealed system wherein all of the gears and shifter mechanism are
sealed and are lubricated.
What the new development consists then is an increase in gear
reduction from a typical present reduction ratio of 15:1 to 45:1 so
that the bowl can be rotated at whatever speed is desired as for
example 23 to 24 rpm in the high range to enable faster charge time
and discharge time whereby less material is spilled and the bowl is
cleaner; and, at the lower range of bowl speed, the aggregate is
protected from overmixing and excessive bowl wear. Because of the
improved bowl gear reduction, ample power is available at the lower
range of bowl rotation so that the bowl can always or nearly always
be rotated and after it has been stopped for excessive periods thus
preventing set up of the aggregate in the bowl resulting in
catastrophic loss of the bowl.
Also, the low range bowl drive speed results in a power saving in
the hydraulic unit (since the hydraulic motor is driven from the
prime mover) and the additional power available contributes to
increased power for the vehicle drive train. Thus, the vehicle can
move over steeper grades and at faster speeds than heretofore.
The operating mechanisms for shifting the plates 24, 26 can be
either manual, hydraulic or pneumatic according to desired
preference.
Although the present invention has been illustrated and described
in connection with a few selected example embodiments, it will be
understood that these are illustrative of the invention and are by
means restrictive thereof. It is reasonably to be expected that
those skilled in this art can make numerous revisions and
adaptations of the invention and it is intended that such revisions
and adaptations will be included within the scope of the following
claims as equivalents of the invention.
* * * * *