Title: Brake system
Abstract: A fluid damping system for brake fluid disposed in a brake line on a vehicle in which the damping system converts incompressible fluid pulses into damped energy by an accumulator which dissipates the energy to remove the pressure pulses from the fluid system.
Patent Number: 6,997,523 Issued on 02/14/2006 to Banoczky, et al.
| Inventors:
|
Banoczky; Bella (1660 Livorna Rd., Alamo, CA 94507);
Trueman; Wayne (3748 Hidden Springs, Ct., El Sobrante, CA 94803);
Bohunicky; Bernard P. (1353 Canada Rd., Woodside, CA 94062)
|
| Appl. No.:
|
401017 |
| Filed:
|
March 26, 2003 |
| Current U.S. Class: |
303/87 |
| Current Intern'l Class: |
B60T 17/04 (20060101) |
| Field of Search: |
138/126,130,131,30,31
303/87
411/378-426
188/151.R,347,352,358
|
References Cited [Referenced By]
U.S. Patent Documents
| 912502 | Feb., 1909 | Squires.
| |
| 3064687 | Nov., 1962 | Natho et al.
| |
| 3430660 | Mar., 1969 | Mitton.
| |
| 3757825 | Sep., 1973 | Givens et al.
| |
| 3893486 | Jul., 1975 | Meyers.
| |
| 4166655 | Sep., 1979 | Spero.
| |
| 4188073 | Feb., 1980 | Ishikawa et al.
| |
| 4220376 | Sep., 1980 | Spero.
| |
| 4301908 | Nov., 1981 | Fukuda et al.
| |
| 5078455 | Jan., 1992 | Washington.
| |
| 5085298 | Feb., 1992 | Sollami.
| |
| 5380074 | Jan., 1995 | Jones.
| |
| 5390989 | Feb., 1995 | Kim.
| |
| 5468056 | Nov., 1995 | Kim.
| |
| 5664848 | Sep., 1997 | Muraski.
| |
| 5753807 | May., 1998 | Trueman et al.
| |
| 5820227 | Oct., 1998 | Spero.
| |
| 6322160 | Nov., 2001 | Loh et al.
| |
| 6347841 | Feb., 2002 | Kim.
| |
Primary Examiner: Schwartz; Christopher P
Attorney, Agent or Firm: Kreten; Bernhard, Weintraub Genshlea Chediak
Claims
I claim:
1. A hydraulic brake pressure damping system, comprising in combination: a brake
actuator operatively coupled to a brake by an interposed line which carries hydraulic
fluid there between, and a fitting having an inlet and an outlet connect to said
line in fluid communication with the fluid, said fitting formed with a hollow channel
between said inlet and outlet and a passageway branching from said channel leading
to a fluid pulse accumulator, and said accumulator located in a housing having
a top piece portion communicating with said fitting at said passageway and a bottom
piece portion having an interior hollow which houses said accumulator, and means
to maintain a cross-section of said channel completely unobstructed at all times
along its entire length; and
wherein said fitting includes a threaded connector attached to a master cylinder,
said connector rotatably mounted on a stem of said fitting and held there by a
swage at a free end of said stem, whereby said system is installed with mere rotation
of the connector and not said fitting.
2. The system of claim 1 wherein said passageway receives a rod having a disc
portion which abuts against said accumulator.
3. The system of claim 2 wherein said accumulator has a small end which abuts
said end wall, surrounded by said a chamfer.
4. The system of claim 1 wherein said bottom piece portion includes a chamfer
adjacent an end wall, said accumulator being centered in said interior hollow and
held centered by said chamfer.
5. The system of claim 1 wherein said accumulator is substantially frusto-conical
and resides within an interior of a housing, said interior having an end wall which
is chamfered so as to center said accumulator.
6. A hydraulic brake pressure damping system, comprising in combination: a brake
actuator operatively coupled to a brake by an interposed line which carries hydraulic
fluid there between, and a fitting having an inlet and an outlet connect to said
line in fluid communication with the fluid, said fitting formed with a hollow channel
between said inlet and outlet and a passageway branching from said channel leading
to a fluid pulse accumulator, said accumulator serving as an energy absorber and
located in a housing having a top piece portion communicating with said fitting
at said passageway and a bottom piece portion having an interior hollow which houses
said accumulator, said top piece having a hollow interior into which said fluid
acts on a reciprocating cylindrical rod, said rod having peripheral seals prohibiting
said fluid therebeyond, said rod having a disc of greater cross-section and overlying
said accumulator and means to maintain a cross-section of said channel completely
unobstructed such that a uniform cross section exits unencumbered by impediments
along the length of said channel at all times along its entire length wherein said
fitting includes a threaded connector attached to a master cylinder, said connector
rotatably mounted on a stem of said fitting and held there by a swage at a fee
end of said stem.
7. The system of claim 6 wherein one end of said channel includes interior threads
dimensioned to receive threads of the brake line.
8. A hydraulic brake pressure damping system, comprising in combination: a brake
actuator operatively coupled to a brake by an interposed line which carries hydraulic
fluid there between, and a fitting having an inlet and an outlet connect to said
line in fluid communication with the fluid, said fitting formed with a hollow channel
between said inlet and outlet and a passageway branching from said channel leading
to a fluid pulse accumulator, and said accumulator having a truncated, conical
shape tapering away from said channel defining a small end and said accumulator
located in a housing having a top piece portion communicating with said fitting
at said passageway and a bottom piece portion having an interior hollow which houses
said accumulator, and means to maintain a cross section of said channel completely
unobstructed at all times along its entire length; and
wherein said bottom piece portion includes a chamfer adjacent an end interior
wall, said accumulator being centered in said interior hollow and held centered
by said chamfer abutting against a periphery of said small end of said accumulator.
Description
FIELD OF THE INVENTION
The following invention relates generally to instumentalities used particularly
for stopping the vehicle. More specifically, the instant invention is directed
to a hydraulic brake system in which damping in the hydraulic circuit occurs.
BACKGROUND OF THE INVENTION
Hydraulic brake systems are common in the automotive world. The incompressible
brake fluid extends from a brake pedal actuated master cylinder to each of the
brakes located on the vehicle wheels. The master cylinder and plural slave cylinders
are used in conjunction with a fluid containing brake line to distribute the flow
of the brake fluid in an appropriate manner to the brakes. In certain situations,
brakes can be applied so severely that one or more wheels can lock up.
Although automatic brake systems have been devised which monitor whether
one or more wheels have locked up and divert fluid in a rapid fashion away from
the locked up brake to ensure maximum braking at times, it is common in vehicles
both with and without automatic brake systems (ABS) to induce pressure pulses in
the non-compressible brake fluid.
For example, with ABS Systems, severe pressure on the brake pedal can result
in a sensation of "chatter" as the valving system diverts brake fluid away from
a brake which is being locked. These fluid pulses stress the system. Even in vehicles
without ABS, anomalies along the interface between the friction pad and the brake
engaging surface can cause fluidic pressure pulses similar to the chatter experienced
with ABS.
The following patents reflect the state of the art of which applicants are aware
and is included herewith to disclose and discharge applicants' acknowledged duty
to disclose relevant prior art. Is respectfully stipulated, however that no single
reference anticipates and no combination of references renders obvious the nexus
of the instant invention as set forth hereafter.
| |
|
| |
U.S. PAT. NO. |
ISSUE DATE |
INVENTOR |
| |
|
| |
912.502 |
Feb. 16, 1909 |
Squires |
| |
3,064,687 |
Nov. 20, 1962 |
Natho, et al. |
| |
3,757,825 |
Sep. 11, 1973 |
Givens, et al. |
| |
3,893,486 |
Jul. 8, 1975 |
Myers |
| |
4,166,655 |
Sep. 4, 1979 |
Spero |
| |
4,188,073 |
Feb. 12, 1980 |
Ishikaw, et al. |
| |
4,220,376 |
Sep. 2, 1980 |
Spero |
| |
4,301,908 |
Nov. 24, 1981 |
Fukuda, et al. |
| |
5,078,455 |
Jan. 7, 1992 |
Washington |
| |
5,085,298 |
Feb. 4, 1992 |
Sollami |
| |
5,380,074 |
Jan. 10, 1995 |
Jones |
| |
5,390,898 |
Feb. 21, 1995 |
Kim |
| |
5,468,056 |
Nov. 21, 1995 |
Kim |
| |
5,664,848 |
Sep. 9, 1997 |
Muraski |
| |
5,753,807 |
May 19, 1998 |
Trueman, et al. |
| |
5,820,227 |
Oct. 13, 1998 |
Spero |
| |
6,322,160 |
Nov. 27, 2001 |
Loh, et al. |
| |
6,347,841 |
Feb. 19, 2002 |
Kim |
| |
|
For example, the patents to Spero U.S. Pat. No. 4,220,376 teaches the use of
a pressure equalizing devices. In addition, Spero has modified the equalizer in
that patent as disclosed in his U.S. Pat. No. 4,166,655. Finally, Spero recognized
the limitations in those two patents by developing a further U.S. Pat. No. 5,820,227.
Columns 1 and 2 of the '227 patent list some of the frailties in Spero's earlier
patents as well as that of the patent to Washington, U.S. Pat. No. 5,078,455.
The remaining patents diverge from the nexus of the instant invention even further.
SUMMARY OF THE INVENTION
The instant invention is distinguished over the known prior art in a multiplicity
of ways. For example, a fitting is provided with a through channel, with the fitting
provided with an inlet and an outlet that allows easy attachment to a brake line
anywhere along the length of the brake line, where it extends typically from the
master cylinder to the brake itself. The fitting includes a passage way which receives
a housing that accommodates an accumulator. The accumulator functions as an absorber
or damper and is disposed within an interior of the housing and is provided with
a truncated conical shape. The accumulator is operatively coupled to a accumulator
rod having a portion which faces towards the channel, but does not extend therein.
The accumulator is guided within the interior of the housing by means of a tapering
bevel along one extremity of the housing adjacent a free end of the accumulator
to act as a guide. A cavity surrounds a major portion of the accumulator and accommodates
distortion of the accumulator in the air space thus provided. A bleed nipple is
disposed on a side of the fitting diametrically opposite from the accumulator housing
and communicates with the channel by means of a nipple branch.
In use and operation, when the non-compressible brake fluid experiences a pressure
pulse, the pressure wave enters into the passageway and exerts a force on the accumulator
rod causing compression of the accumulator and distortion of the accumulator within
the open cavity which surrounds the accumulator defined by the space between the
accumulator and housing. Because there is no air in the brake fluid circuit, the
response of a pressure wave is immediate and directed to the accumulator instantaneously
which therefore dissipates the pressure wave in an immediate fashion since the
accumulator is immediately distended and distorted in the available open cavity
air space around the accumulator. Thus, pressure equalization is effected.
OBJECTS OF THE INVENTION
Accordingly, is a primary object of the present invention to provide
a new, novel and reliable equalization device for removing pressure pulses in brake systems.
A further object of the present invention is to provide a device as characterized
above which is extremely durable in construction, easy to retro fit on existing
vehicles and safe to use.
A further object of the present invention is to provide a device as characterized
above which lends itself to mass production techniques.
A further object of the present invention is to provide a device which can be
deployed
substantially anywhere along the length of brake line.
A further object of the present invention is to provide a device as characterized
above which can be used on all four brakes of a vehicle.
A further object of the present invention is to provide a device as characterized
above which provides instantaneous response to the pressure wave that is sent through
the fluid braking system and is immediately resolved.
A further object of the present invention is to provide a device where the brake
fluid can be easily bled to remove air from the system.
A further object of the present invention is to provide a device as characterized
above which does not in and of itself induce its own turbulence as is common in
the prior art.
Viewed from a first vantage point, it is an object of the present invention
to provide a hydraulic brake pressure damping system, comprising in combination:
a brake actuator operatively coupled to a brake by an interposed line which carries
hydraulic fluid there between, and a fitting having an inlet and an outlet connect
to said line in fluid communication with the fluid, said fitting formed with a
hollow channel between said inlet and outlet and a passageway branching from said
channel leading to a fluid pulse accumulator, said accumulator located in a housing
having a top piece portion communicating with said fitting at said passageway and
a bottom piece portion having an interior hollow which houses said accumulator,
and means to maintain a cross-section of said channel completely unobstructed at
all times along its entire length.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic depiction of the apparatus according to the present invention
in its deployed condition.
FIG. 2 is a perspective view of the apparatus according to the present invention.
FIG. 3 is a sectional view of the apparatus according to the present invention
in its relaxed, "non-pressure pulsed" state.
FIG. 4 is a sectional view similar to FIG. 3 showing the reaction of the system
in response to a pressure wave.
FIG. 5 is an exploded parts view of the apparatus according the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, when like numerals relate to like parts, reference
numeral
10 is directed to the damping system according to the present invention.
In its essence, the damping system (
10) includes a fitting (
20)
(FIG. 2) having central channel (
26) (FIG. 3) which is oriented in fluid
communication with the brake fluid by its placement anywhere along the length of
a brake line (L) (FIG. 1), but is most efficiently deployed adjacent the master
cylinder (MS). The channel (
26) includes an interior passageway (
50)
extending off therefrom that leads to a housing (
90) (FIG. 2) within which
an accumulator (
80) (FIG. 5) is operatively deployed. Because the brake
fluid in incompressible, shock waves transmitted through the brake fluid will arrive
at the passageway (
50) of the damping system (
10) and be dissipated
by the accumulator (
80).
More particularly, and with reference to the drawing FIGS. 1 through 5, the
damping system (
10) is operatively deployed within the existing braking
network of a vehicle as shown in FIG. 1. A brake pedal (
2) is operatively
coupled to a series of links (
6), (
8), which lead to a piston shaft
(
12) that allows reciprocal movement of pistons (
4) located within
the master cylinder (MS). The brake action initiated at the pedal (
2) causes
bi-directional movement of the working fluid in the direction of the double ended
arrow (A). The master cylinder includes a brake fluid reservoir (
14) accessible
by a cap (
16). The damping system (
10) can be deployed anywhere along
the length of the brake line (L). The brake line (L) extends from the master cylinder
(MS) and travels to each of the wheels that include a rotor (R) at the brake (B).
Calipers (C) receive the free end of the brake line (L) and internal routing (not
shown) lead to brake pads (P) so that the pads, under fluidic pressure grab rotors
(R) to effect braking. A check valve (
18) is deployed in line to control
bi-directional flow.
In certain instances, for example with ABS, the ABS modulator valves actuate
quickly
and at a high frequency in order to prevent wheels from locking up. In other situations,
imperfections on the rotor or out of round conventional brake drums will send pressure
pulses through the fluid system. When pulsing occurs, the system's efficiency will
have been compromised. As a result, the damping system (
10), which can be
deployed anywhere along the length of the line (L) is fashioned to meet with the
traditional coupling that exists between the line (L) and its connection at the
master cylinder (MS). By removing that coupling, the damping system (
10)
mimics the coupling geometry that exists between the master cylinder and brake line.
More specifically, and with reference to FIGS. 3 and 5, fitting (
20)
(FIG. 2) of the damping assembly (
10) includes an inlet (
22) (FIG.
3) and an outlet (
24) separated from each other on the fitting (
20)
by means of an unobstructed central channel (
26). The fitting (
20)
has an exterior body formed with a plurality of facets (
28) and has a stem
(
30) (FIG. 5) projecting from one end of the faceted body over which the
bore (
34) of a connector (
38) is deployed. The connector (
38)
is formed with a plurality of threads at one end and is held on the stem (
30)
by means of a swage (
32) formed on the stem (
30). As thus described,
the connector threads (
38) are free to rotate on the stem (
30). A
hex nut (
36) is integrally formed with the connector threads (
38)
so that the threads can be advanced into an interior bore of the master cylinder
without turning fitting (
20).
In addition, an opposite end of the channel (
26) (FIG. 3) includes interior
threads (
42) (FIG. 5) which are dimensioned to receive the threads of the
brake line (L). Thus, the instant invention can be plumbed into the brake system
with a minimum amount of modifications to the brake system of an existing vehicle.
The channel (
26) of the fitting (
20) communicates with a passageway
(
50) extending perpendicularly from the channel (
26). The passageway
(
50) includes a threaded interior bore (
56) (FIG. 4) dimensioned
to receive threads (
58) (FIG. 5) of a top piece upper portion (
70)
along its right hand side of FIG. 3 of a housing (
90). The top piece (
70)
includes a central interior bore (
54) (FIG. 4) with respect to threads (
58)
(FIG. 5). The interior bore (
54) leads to a cylinder (
75) (FIG. 3)
which receives an accumulator rod (
76) (FIG. 4) formed of generally cylindrical
configuration and reciprocally disposed within the cylinder (
75) (FIG. 3)
and which is in fluid communication with the passageway (
54) (FIG. 4). The
accumulator rod (
76) (FIG. 4) also includes at an end thereof remote from
the channel (
26) (FIG. 3) a disc portion (
78) integrally formed with
the cylindrical rod (
76) (FIG. 4). The disc portion (
78) serves as
a stop against the upper portion (
70) (FIG. 3) along its right hand side
of FIG. 3. A periphery of the cylindrical rod (
76) (FIG. 4) is girded by
a pair of "O" rings (
74) (FIG. 5) imbedded within the interior cylinder
walls (
75) (FIG. 3) of the upper portion (
70). An exterior of the
upper portion (
70) includes a pair of opposed flat surfaces (
62)
(FIG. 3) dimensioned to receive a wrench thereon for advancement of the threads
(
58) in and out of the threaded interior bore (
56). A plurality of
further threads (
64) are located on the upper portion (
70) dimensioned
to mesh with threads (
86) located on an interior hollow (
94) of bottom
piece lower portion (
91) of the housing (
90). The bottom piece (
91)
interior hollow (
94) is cylindrical (
92) adjacent its juncture with
the disc portion (
78) and its dimension is substantially equal to the radius
of the disc portion (
78) of accumulator rod (
76). An end wall (
96)
of the bottom piece (
91) remote from the disc (
78) seals the housing
(
90). A transition (
88) exists between the interior bore (
92)
and the end wall (
96) which is chamfered (
88) so that an accumulator
(
80) placed within the lower portion will always be centered within the interior.
The accumulator (
80) (FIG. 5) is essentially a frusto conical element
having a base (
82) which addresses the disc (
78) and is substantially
of the same radius, and an end (
84) parallel to and remote from the base
(
82) has a radius substantially the same as the end wall (
96). The
chamfer (
88) assures that the truncated cone shaped accumulator (
80)
is self centering because the bevel or chamfer (
88) urges the accumulator
(
80) to remain symmetric to the long axis of the housing.
A gap (
94) exists between accumulator (
80) and the hollow defined
by cylinder (
92) for the inclusion of air in the free space gap (
94).
The pair of "O" rings (
74) installed in grooves (
72) of interior
walls of upper portion (
62) that circumscribe the accumulator rod (
76)
assures that no brake fluid will enter into the free space gap (
94) (FIG.
3). Thus, only air which had been provided during assembly is present in the gap (
94).
A further threaded bore (
44) (FIG. 5) is provided in opposition to the
passageway
(
50). A nipple (
40) having a thread (
52) complemental to the
thread (
44) is received within thread (
44) and the nipple (
40)
includes a wrench receiving facet (
48) for rotation during installation
and bleeding. The nipple (
40) allows the system to be purged of air within
the fluidic line (L) and channel (
26).
Once the system has been plumbed into the existing brake line, and after the
air has been bled from the brake line (L) and passageway (
50) and channel
(
26), the system will operate as shown in FIGS. 3 and 4. When a fluidic
pressure pulse in experienced in the incompressible brake fluid, the accumulator
rod (
76) will move from the FIG. 3 position to the FIG. 4 position. This
causes the accumulator (
80) to distort and occupy more of the available
free space gap (
94) by the distortion of the accumulator within that hollow area.
Moreover, having thus described the invention, it should be apparent that
numerous structural modification may be resorted to without departing from the
scope and fair meaning of the instant invention as set forth here and above and
defined here and below by the claims.
*
