U.S. patent number 3,865,523 [Application Number 05/342,071] was granted by the patent office on 1975-02-11 for continuous flow rotary pump.
Invention is credited to Samuel J. Baehr.
United States Patent |
3,865,523 |
Baehr |
February 11, 1975 |
Continuous flow rotary pump
Abstract
In a rotary pump of the type providing for continuous
displacement and flow of a fluid material, said pump includes a
housing having an intake port and an outlet, a pair of intermating
rotor means disposed for rotation within said housing, and said
rotors are in communication with said inlet port and outlet so as
to provide for the displacement of said fluid material. An
elongated channel is formed communicating with each of the inlet
port and the outlet so that as fluid material is drawn into the
housing it will be exposed to the helical spacings formed along the
length of the rotor means, at their point of intermeshing, and
likewise said fluid material will be discharged under the induced
pressure that forms along the elongated channel communicating with
the outlet of said pump housing.
Inventors: |
Baehr; Samuel J. (La Prairie,
IL) |
Family
ID: |
23340207 |
Appl.
No.: |
05/342,071 |
Filed: |
March 16, 1973 |
Current U.S.
Class: |
418/201.1 |
Current CPC
Class: |
F04C
2/16 (20130101) |
Current International
Class: |
F04C
2/16 (20060101); F04C 2/00 (20060101); F01c
001/16 () |
Field of
Search: |
;418/201,202 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Husar; C. J.
Attorney, Agent or Firm: Denk; Paul M.
Claims
Having thus described the invention what is claimed and desired to
be secured by Letters Patent is:
1. In a positive displacement rotary pump of the type designed for
inducing continuous transfer of fluid material comprising, a pump
casing having side and end walls, said casing having a pair of
communicating and parallel cavities formed therein, said casing
having an intake port and an outlet port provided upon its
approximate opposite sides and opening into said cavities at the
location of their communication within said casing, said casing
being formed having channels provided upon its interior cavity
surfaces, one of said channels being in communication with the
intake port, and the other of said channel being in communication
with the outlet port, said channels being elongated and arranged
substantially in parallel with the length of said cavities, a pair
of parallelly arranged and intermeshing rotor means, one of each
rotor means disposed for close tolerance rotation within each of
said cavities, said rotor means intermeshing at the vicinity of the
communication between said casing cavities, each rotor means having
a shaft extending axially from each of its ends, said shafts being
bearing mounted within the end walls of said casing, one of said
rotor means including a series of helical ribs formed upon its
surface, the other of said rotor means including a series of
helical flutes formed upon its surface, said rotor ribs and flutes
being intermeshed, a plurality of said ribs and flutes being
simultaneously in communication with either the elongated intake
port and outlet port channels for providing pulse-free displacement
of fluid materials and the continuous discharge of multiple
quantities of said fluid material along the length of said rotor
means, and at least one of said intermeshed ribs and flutes always
being simultaneously in communication with both the intake and
outlet channels during operation of said rotary pump.
2. The invention of claim 1 wherein said helically arranged ribs
and flutes of the rotor means extend approximately 140.degree. to
180.degree. around the rotor means, and each further extends from
end to end of said rotor means.
3. The invention of claim 1 and including a drive means connecting
to and providing for rotation of said rotor means.
4. The invention of claim 3 and including a pair of intermeshing
spur gears, one of each spur gears operatively associated with one
of said rotor means, the operation of said drive means provided for
contrarotation of said spur gears and rotor means for effecting
displacement of the fluid material.
5. The invention of claim 1 wherein said intake port and outlet are
disposed laterally on opposite sides of said housing and proximate
the location where said pair of rotor means intermate.
6. The invention of claim 1 wherein said axial shafts are bearing
mounted and form a fluid tight seal in the end walls of said
casing.
7. The invention of claim 1 wherein the helical ribs are in the
form of projecting lobes.
8. The invention of claim 7 wherein the rotor lobes and flutes are
semicircular in design.
9. The invention of claim 1 wherein said channels have a length
approximating the length of the rotor means.
10. The invention of claim 1 wherein the height of the channel at
the intake port has upper and lower reaches disposed approximately
180.degree. from the respective upper and lower reaches of the
channel communicating with the outlet.
11. The invention of claim 1 wherein each rib is helically formed
approximately 180.degree. around the rotor means, and each flute is
formed helically approximately 140.degree. around its rotor means.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to a pump, but more particularly
pertains to a fluid displacement rotary pump wherein the fluid
material is continuously and efficiently transferred under uniform
flow with negligible pulsatory effects.
There are a multitude of various types of rotary pumps that are
available in the prior art, incorporating a variety of combination
of gears that furnish displacement of fluids or other materials.
Most of these earlier pumps utilize some form of a star wheel of
other type of longitudinally ribbed gears which simply intermesh to
provide for a forced transfer of fluid, and particularly in a
manner which provides a pulsatory type transfer of such fluids. For
example, rotary pumps of the type defined as the Pappenheim type
rotary pump and the star-wheel-geared type rotary pump show early
embodiments of the type of pumps utilizing longitudinally arranged
intermeshing gears. Most of these types of pumps incorporate a
simple annular intake port that communicates with one side of the
pump proximate the location of the intermeshing relationship
between said pair of gears, while the outlet also comprises a
simple pipe type discharge positioned proximate the other side of
the pump and oppositely from the intake port. While some of these
pumps are effective in providing displacement of liquids and gases,
such as while the rib spacings or grooves of these gears convey the
fluid around the inner periphery of the housing, these segmented
quantities of fluid are then discharged from the outlet as separate
and distinct discharges which create somewhat of a pulsation or
rhythmatic form of flow pattern for the pump.
The present invention obviates the deficiencies inherent in the
aforesaid type of prior art rotary pumps, and improves upon their
operation through the use of helical formed rotors that communicate
with inlet and outlet ports along their entire length so as to
provide for an overlapping and continuous intake of fluid into the
pump, and simultaneously provides continuity of discharge of fluid
from the same series of the rotor spacings at the same time. Hence,
the pulsatory effect present in the operation of prior art pumps is
eliminated by constructing the rotary pumps in the manner as will
be hereinafter described. It is recognized that helically
constructed gears have been utilized in screw type pumps, but it is
not believed that helically formed rotors communicating along their
length with the intake and discharge of fluid, has been
performed.
It is, therefore, the principal object of this invention to provide
a displacement type rotary pump in which fluid material is
continuously taken into the pump housing and likewise discharged in
a manner which eliminates any oscillatory pattern in the flow of
the fluid material.
Another object of this invention is to provide a rotary pump
wherein the helical rotors, or more particularly their spacings or
flutes, provide a constant multiple intake of fluid material, while
providing a multiple simultaneous discharge of quantities of fluid
disposed within a series of said spacings of flutes from a single
outlet.
Another object of this invention is to provide a helical rotor
displacement pump which may be driven from a single or dual drive
means depending upon the viscosity of the material being
transferred.
Another object of this invention is to provide a pump wherein its
intermeshing rotor means are provided with multiple ribs or lobes,
arranged helically, so that a plurality of said lobes, or more
particularly there intermediate spacings, are exposed to an
elongated channel communicating with the intake port to provide a
form of multiple and continuous absorption or drawing in of fluid
into the rotor means for immediate pumping.
An additional object of this invention is to provide a displacement
pump wherein a plurality of the parabolic or conic lobes of the
multi-helical ribbed rotor are exposed simultaneously to an
elongated channel communicating with the outlet so as to provide
for a simultaneous discharge of multiple quantities of fluid out of
said pump.
These and other objects will become more apparent to those skilled
in the art upon reviewing the following summary, and upon studying
the description of the preferred embodiment when viewed with the
drawings.
SUMMARY OF THE INVENTION
This invention, as previously described, comprises a positive
displacement rotary pump of the type designed for inducing transfer
of fluid material, and said pump includes a casing or housing with
formed cavities therein communicating with an intake port and an
outlet to provide said transfer of the fluid material. The intake
port and the outlet are arranged at approximate opposite sides of
said casing, and are disposed within the influence and vicinity of
the intermeshing between a pair of helical rotors disposed for
contrarotation within said housing cavities, so that fluid may be
drawn into the pump due to the pressure decrease caused at the
intake port upon rotation of said rotors, and likewise, transferred
or induced out of the pump at its outlet due to the pressure build
up at this juncture. The unique feature of this invention is the
provision of rotor means that incorporate helical formed gear like
ribs and flutes, the same being intermeshed with respect to each
other within the pump, and further including elongated channels,
one communicating with each of the intake port and the outlet, with
said channels being arranged parallel with respect to the
disposition of the pair of rotors, and also being located within
proximity of the meshing of said rotors. Hence, at any given moment
during the operation of the pump, a series of the ribs, or lobes,
and corresponding flutes will be exposed to the intake channel,
while at the same time a series of the same or other ribs or flutes
further around the circumference of the rotor means will be exposed
to the outlet channel, communicating with the outlet port, so that
while fluid is being drawn into the pump, due to the inducing and
creation of low pressure at this location, said fluid will pervade
within the spacings between a series of the rotor ribs, or the
rotor flutes, so as to provide for a multiple intake of fluid by
said contrarotating rotors, and likewise as the fluid is being
discharged from the pump it will be continuously urged out of the
multiplicity of spacings between said ribs or flutes as they become
exposed to the elongated channel communicating with the outlet port
of said pump. Hence, there is continuity in the transfer of fluid
during usage of this pump means, as distinct from the type of
rotary pumps available in the prior art that simply utilize gears
having longitudinally oriented ribs that simply displace discrete
quantities of fluid as each rib bypasses the intake port, and
likewise incrimentally discharges separate quantities of fluid as
these gear ribs rotate past the outlet port.
A further novel feature of this invention is that since
particularly the rotor lobes are designed so that they extend
approximately one hundred eighty helical degrees, more or less,
around their respective rotors over their length, it is anticipated
that as one end of a particular lobe spacing or flute may be
completing exposure to the inlet channel its other end is just
becoming exposed to the outlet channel and creating a pressure that
forces fluid transfer out of the pump.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, FIG. 1 discloses an isometric view of the pump
housing and external spur gears that are driven during operation of
the rotary pump of this invention;
FIG. 2 provides an end view of the rotary pump disclosed in FIG.
1;
FIG. 3 provides a right side view of the rotary pump shown in FIG.
1;
FIG. 4 provides a side view of the rotor means of this invention
being removed and separated from their disposition within the pump
housing cavities;
FIG. 5 provides a transverse sectional view taken along the lines
5--5 of FIG. 3; showing the disposition of the rotor means
positioned within the housing cavities and their relationship with
respect to the intake port and channel, in addition to the outlet
channel and port; and
FIG. 6 provides a transverse sectional view taken along a similar
line as 5--5 of FIG. 3, but showing a modification in the design of
the intake port channel.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings, and more particularly in FIGS. 1 through 3, there
is disclosed a casing or housing 1 for a rotary displacement pump
A, having the usual intake 2 and outlet 3 disposed approximately
along the sides of the housing, with the entire pump being provided
with a base 4 to stabilize it during its operational use. As shown,
the inlet and outlets may be provided with flanges, as at 5 and 6,
having the usual apertures provided therethrough, so as to provide
means for hermetically sealing other conduits or pipelines thereto
upon installation of said rotary pump.
Projecting externally of the casing 1 are a pair of shafts 7 and 8
each mounting a spur gear 9 and 10, respectively, said gears having
the usual gear teeth, as shown, around their periphery, and being
intermated to provide for contrarotation of a pair of rotors
disposed within the pump as will be hereinafter described. See FIG.
4. These gears 9 and 10 are mounted for rotation upon their pair of
shafts 7 and 8, as aforesaid, which project and extend outwardly of
the casing 1 from their integral connection with their respective
rotors 11 and 12, which are supported for intermeshing rotation
within said casing. Drive means (not shown) may be provided for
rotating either one of the gear 9 and 10, so as to furnish the form
of rotation of the rotors 11 and 12 within said pump as previously
described. It may also be noted that stub shafts 13 and 14 are
integrally structured with their respective rotors 11 and 12, and
are bearing mounted with respect to the opposite end of the pump
housing. Preferably, these shafts 7 and 8 and 13 and 14 are bearing
mounted in a fluid tight seal with respect to their end walls.
Also in FIG. 4, the two rotors 11 and 12 are shown independent and
separated from their usual intermeshed mounting within the casing
1, and said rotors are each provided with helical means formed upon
their surfaces that provides for their mating relationship as when
rotated within the casing 1. For example, the upper rotor 11 is
provided with a series of semicircular projecting ribs, or lobes,
or other conic shapes, as at 15, (See FIG. 5), and they are
designed for close tolerance mating within correspondingly shaped
flutes 16, in this instance being semicircular as shown, formed
within the peripheral surface of the rotor 12. Each lobe 15 of the
rotor 11 is formed as a helix, extending approximately 180.degree.
spirally around the said rotor and extending from end to end.
Likewise, each formed flute 16 provided within the surface of the
rotor 12 is arranged helically around its periphery to that degree
necessary to provide for its mating relationship with and adjacent
lobe as the rotor 11 is revolved, and in practice, it would appear
that each flute 14 is arranged spirally approximately 140.degree.
around the surface of the rotor 12, from end to end. Obviously the
angular degrees of the helically formed lobes and flutes may vary,
although in the preferred embodiment, it has been found that the
degrees of spiral previously described provides an effectively
designed mating relationship between a rotor 11 and the rotor 12.
It should also be commented at that this juncture that while the
preferred embodiment discloses lobes and flutes formed upon the
peripheral surface of the rotors 11 and 12, other shapes for
intermating gearlike means formed upon the surface of intermeshing
rotors will operate under the principles of this invention. For
example, various other types of parabolic shapes for the lobes 13,
and equivalent cavities or flutes 14 may operate under the
principle of this invention to provide an efficient rotary pump,
provided that such parabolic shapes are formed helically of their
respective rotors. Also, in a modified design, it is likely that
the rotor 11 may be designed of slightly greater diameter than the
rotor 12, to insure proper mating of the helical means formed upon
their surfaces.
Of particular significance in this invention is the relationship
between the intermating of the rotor means lobes 15 within the
flutes 16 provided upon and within the respective rotors 11 and 12.
As previously described, the shaft 7 extends from one end of the
rotor 11, through the end wall 17 of the pump casing, and has
mounted thereon the spur gear 9. Likewise, the shaft 8
correspondingly extends from the end of the rotor 12, also through
the end wall 17, and has the spur gear 10 mounted thereupon. When
either the shafts 7 or 8 is driven by means of a drive means (not
shown), the meshing of the gears 9 and 10 provide for the
contrarotation of their two rotors 11 and 12. Under ideal
conditions, only the teeth of the spur gears 9 and 10 are in
contact in their intermeshing, whereas there is only a very close
tolerance fitting, perhaps only within a thousandth of an inch,
although preferably not in contact, of the lobes 15 within their
respective flutes 16 of the two rotors. In this manner, these two
members are in close enough contact to provide for the desired
reduction of pressure on the intake side of the rotary pump, and
the increase of pressure upon the outlet side of said pump. In this
manner, there is no frictional engagement between the two rotors 11
and 12, and no frictional contact is being effected which can cause
their accelerated deterioration. On the other hand, and although
such may effect a slight decrease in the efficiency of operation of
the pump, it is just as likely that no spur gears may be
intermeshed upon the ends of the shafts of the two rotors, but
rather, one of said shafts 7 or 8 may be driven and the two rotors
11 and 12 may provide for their own driving engagement by means of
a particular lobe 15 coming into contact within a mating flute 16
to provide the drive for this displacement pump. It is also shown
in FIG. 5 that the two rotors 11 and 12 are arranged in close
tolerance fitting within the cavities 18 and 19 of the casing 1,
and said cavities are in communication so as to allow for the
aforesaid mating of the rotors. This close tolerance fitting of the
rotors also applies with respect to their ends which are also
maintained a close tolerance relationship with the interior
surfaces of the end walls 17 and 17a, or may even be sealed
thereat, as through the use of O-rings, or the like.
In FIG. 5, it can be seen that the intake port 2 communicates with
a channel 20 and this channel is rather elongated in length,
preferably extending a corresponding distance within the casing
that is equal to the length of the rotors 11 and 12, although it
may be of a shorter length. Likewise, the outlet 3 also
communicates with another formed channel 21, that is also elongated
in design, and extends preferably the length of the casing cavities
18 and 19. The purpose of these elongated channels is to provide
for exposure of a series of the lobes 15, or their intermediate
spacings, in addition to the flutes 16, simultaneously to the
intake port of the pump, and due to the helical formation of said
lobes and flutes, intake of fluid by respective rotors will occur
continuously and in an overlapping fashion due to the multiple
exposure of the helical flutes and lobes to the quantity of fluid
drawn into and disposed along the length of the channel 20.
Furthermore, as the rotors are contrarotated, as for example, while
the top rotor 11 may be rotating clockwise, and the bottom rotor 12
rotated counterclockwise, the fluid being pumped will be
continuously exposed to the elongated channel 21, and its
communicating outlet 3, over a series of the helical lobes and
flutes, so as to provide a continuous and overlapping of fluid
discharge without pulsation, from said pump. This is distinct from
prior art types of rotary pumps wherein fluid is sequentially
pumped by longitudinally arranged gears which causes a pulsation or
incremental discharge of fluid out of an outlet port.
A slight modification in this invention is disclosed in FIG. 6
wherein is shown a more precision design for the intake port 2
communicating with a channel 22 which is once again elongated in
design, as aforesaid, extending approximately the length of the
rotors 11 and 12, but this channel is disclosed as having a height
and depth extending about the midpoint of the rotor 11, in addition
to below the midpoint of the rotor 12. More specifically, and since
it was previously described that the lobes 15 on the rotor 11 are
formed helically approximately 180.degree., it can be seen that the
upper reaches 23 of the channel 22 is arranged almost diametrically
opposed to the upper reaches 24 of the channel 21, and in this
relationship, a particular intermediate spacing between a pair of
the lobes upon a rotor 11 will just become closed against the inner
surface 18 of the casing 1, and just shortly thereafter the
opposite end of the spacing between the same pair of lobes, which
is disposed approximately 180.degree. around the rotor, will just
open into communication with the channel 21 to commence to
discharge the pressurized fluid from the outlet 3. In a similar
arrangement, the lower reach 25 of the channel 22 is disposed
approximately diametrically across from the lower reach 26 of the
channel 21 so that as a particular flute has been charged with
fluid and becomes somewhat sealed against the inner surface 19 of
the casing cavity, upon movement for a few more degrees the
opposite end of said flute, which is arranged approximately around
the rotor 12 probably about 140.degree., will just commence to pass
the location 26 and enter into open communication with the channel
21 for discharging its retained fluid out of the pump and its
outlet.
While seven lobes and nine flutes are shown in the preferred
embodiment obviously other numerical quantities of lobes and flutes
can be utilized in the combined rotors of this invention. Also,
while the helix of the lobes have been described as extending
approximately 180.degree. around the rotor from end to end, it is
likely that other degrees of turn can be constructed into the
rotors. And in addition, if, for example, less or more than
180.degree. is used for the spiral arrangement of the lobes, then
the reaches 23 and 25 for the mofified intake channel 22 may be
varied accordingly, so as to change the capacity of the pump.
It should be obvious that a variety of fluids may be transferred in
this style of a rotary pump, and such fluids may comprise air or
other gases, liquids, or the like. The size of the design of the
outlet channel 21 will depend upon the nature of the fluid being
pumped, and where the fluids are more compressible, such as a gas
or an air, then the channel 21 will be designed at a lesser volume
so as to allow for the pump to build up sufficient pressure of the
gas forced into said chamber 21 and induce its transfer out of the
outlet port 3.
Various modifications in the design of this rotary pump may occur
to those skilled in the art in the light of the foregoing
disclosure. The description provided is for the preferred
embodiment, and any such variations, within the spirit of the
principle of this invention and within the scope of the appended
claims, are intended to be covered by patent protection. The
described embodiment is merely illustrative of the overall
principle of this invention.
* * * * *