US 8,037,898 B2 · Reservoir tank for vehicle brake system

Abstract

A reservoir tank for a vehicle brake system has a tank body including upper and lower shells joined together along mating surfaces. A float and a fluid level sensor are mounted in a fluid level detecting chamber defined in the tank body. The float is fitted on a shaft of the fluid level sensor. A partition plate is fitted in the lower shell to restrict a flow of hydraulic fluid into and out of the fluid level detecting chamber. The partition plate is disposed near the top end of the shaft of the fluid level sensor to restrict the distance by which the float can move vertically. A filter, the fluid level sensor and the partition plate are all set in the lower shell. The filter and the partition plate having their top ends pressed against the bottom ends of partitioning walls of the upper shell. Thus, the filter and the partition wall are held in position in the tank body between the upper and lower shells. No separate retainer for the float is necessary because the partition plate serves also as a float retainer.

Drawings

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Drawings

Claims5

Dependent claims

A reservoir tank for use in a brake system comprising:

a tank body including an upper shell having a bottom mating surface and a lower shell having a top mating surface, said upper and lower shells being joined together along said top and bottom mating surfaces;
said upper and lower shells including partition walls which divide an interior of said tank body into a plurality of chambers including a fluid level detecting chamber, thereby preventing pulsation of hydraulic fluid in said tank body, said fluid level detecting chamber being located in said lower shell;
a fluid level sensor mounted in said fluid level detecting chamber;
a float vertically movably mounted in said fluid level detecting chamber;
and
a partition plate for restricting a flow of hydraulic fluid into and out of said fluid level detecting chamber;
said partition plate comprising a main body and an upwardly extending flange provided along and over the entire outer peripheral edge of the main body, and being in engagement, at a connecting portion of the partition plate where the flange is connected to the main body, with a shoulder formed on one of the partition walls of the lower shell defining said fluid level detecting chamber at its top end portion;
said partition plate being disposed so as to oppose said float, thereby restricting a distance by which said float is vertically movable in said fluid level detecting chamber;
wherein each of said float, said fluid level sensor and said partition plate is mounted in said lower shell so as to be entirely accommodated in said lower shell with no portions of said float, said fluid level sensor and said partition plate protruding upwardly from said top mating surface;
said fluid level sensor having a vertical shaft on which said float is vertically movably mounted;
said partition plate being disposed near a top end of said vertical shaft and being in engagement with said shoulder;
the float being axially slidable along the shaft between a first position in which, with the partition plate in engagement with said shoulder, the float abuts the partition plate and is prevented from further moving in a direction toward the top end of the shaft and a second position in which the float is more remote from the top end of the shaft than when the float is in the first position;
the shaft being free of any structure joined to the shaft that prevents separation of the float from the top end of the shaft;
wherein said top and bottom mating surfaces are joined together by melting, and a top end surface of said flange of said partition plate and a bottom end surface of one of the partition walls of the upper shell are joined together by melting;
and
wherein the main body of the partition plate has a top surface and a bottom surface, the bottom surface including an upwardly protruding substantially dome-shaped portion defining a substantially dome-shaped interior space, and an aperture is formed in the dome-shaped portion of the bottom surface at its highest point so as to extend through the main body of the partition plate to its top surface.

13 more elements

A reservoir tank for use in a brake system comprising:

a tank body including upper and lower shells joined together along mating surfaces thereof;
said upper and lower shells including partition walls which divide an interior of said tank body into a plurality of chambers including a first chamber into which hydraulic fluid flows from outside the tank body and from which hydraulic fluid flows out of the tank body, and a fluid level detecting chamber, thereby preventing pulsation of hydraulic fluid in said tank body, said fluid level detecting chamber being located in said lower shell;
a filter mounted in said first chamber;
a fluid level sensor mounted in said fluid level detecting chamber and having a vertical shaft;
a float mounted in said fluid level detecting chamber so as to be vertically movable along said vertical shaft;
said filter, said float and said fluid level sensor being mounted in said lower shell, and
a partition plate for restricting a flow of hydraulic fluid into and out of said fluid level detecting chamber, said partition plate comprising a main body and an upwardly extending flange provided along and over the entire outer peripheral edge of the main body, and being in engagement, at a connecting portion of the partition plate where the flange is connected to the main body, with a shoulder formed on one of the partition walls of the lower shell defining said fluid level detecting chamber at its top end portion;
said partition plate being disposed near a top end of said vertical shaft, and being in engagement with said shoulder, thereby restricting a distance by which said float is vertically movable along said vertical shaft by abutting said float;
said upper shell having a port through which hydraulic fluid can be supplied into said tank body;
wherein said top and bottom mating surfaces are joined together by melting with said filter held in position in said tank body between said upper and lower shells, and wherein a top end surface of said flange of said partition plate and a bottom end surface of one of the partition walls of the upper shell are joined together by melting;
and
wherein the main body of the partition plate has a top surface and a bottom surface, the bottom surface including an upwardly protruding substantially dome- shaped portion defining a substantially dome-shaped interior space, and an aperture is formed in the dome-shaped portion of the bottom surface at its highest point so as to extend through the main body of the partition plate to its top surface.

9 more elements

A reservoir tank for use in a brake system comprising a tank body including upper and lower shells joined together along mating surfaces;

said upper and lower shells including partition walls which divide an interior of said tank body into a plurality of chambers including a fluid level detecting chamber, thereby preventing pulsation of hydraulic fluid in said tank body, said fluid level detecting chamber being located in said lower shell;
a fluid level sensor mounted in said fluid level detecting chamber;
a float vertically movably mounted in said fluid level detecting chamber;
and
a partition plate for restricting a flow of hydraulic fluid into and out of said fluid level detecting chamber;
said partition plate comprising a main body and an upwardly extending flange provided along and over the entire outer peripheral edge of the main body, and being in engagement, at a connecting portion of the partition plate where the flange is connected to the main body, with a shoulder formed on one of the partition walls of the lower shell defining said fluid level detecting chamber at its top end portion;
said partition plate being disposed in engagement with said shoulder so as to oppose said float, thereby restricting a distance by which said float is vertically movable in said fluid level detecting chamber by abutting said partition plate;
wherein said mating surfaces of the upper and lower shells are joined together by melting, and a top end surface of said flange of said partition plate and a bottom end surface of one of the partition walls of the upper shell are joined together by melting;
and
wherein the main body of the partition plate has a top surface and a bottom surface, the bottom surface including an upwardly protruding substantially dome-shaped portion defining a substantially dome-shaped interior space, and an aperture is formed in the dome-shaped portion of the bottom surface at its highest point so as to extend through the main body of the partition plate to its top surface.

7 more elements

Dependencies are inferred from the claim text.

Description2,163 words

Summary1,040 words

#The present invention relates to a reservoir tank mounted to a master cylinder or a hydraulic booster of a vehicle brake system.

#A typical conventional reservoir tank 10 is shown in FIG. 6B, which comprises a tank body 1 comprising a lower shell 1a and an upper shell 1b, which are joined together by melting their mating surfaces with a hot plate H (FIG. 6A), putting the top shell 1b onto the lower shell 1a so that their molten mating surfaces contact each other, and allowing the mating surfaces to harden so as to be fixed to each other.

#The reservoir tank 10 includes partition walls 2 that divide the interior of the tank body 1 into a plurality of chambers, thereby minimizing pulsation of hydraulic fluid F in the tank body, a filter 4 provided in one of the chambers through which hydraulic fluid F flows into and out of the reservoir tank, and a float 5 and a fluid level sensor 6 provided in a fluid level detecting chamber 3. The flow of hydraulic fluid F into and out of the fluid level detecting chamber 3 is restricted by a partition plate 7. The upper shell 1b has a fluid supply port 8. (This particular type of reservoir tank 10 is disclosed in JP patent publication 11-20660.)

Brief description of the drawings6 figures

#Other features and objects of the present invention will become apparent from the following description made with reference to the accompanying drawings, in which:

#FIG. 1 is a partially cutaway front view of the reservoir tank embodying the present invention;

#FIG. 2 is a plan view of the same with the upper shell omitted;

Detailed description997 words

#Now referring to FIGS. 1-5, the reservoir tank 10 embodying the present invention is used in a vehicle brake system for controlling brake hydraulic pressure of the vehicle brakes. The reservoir tank 10 includes a tank body 11 comprising a lower shell 11a and an upper shell 11b, which are both formed of a synthetic resin, and mounted to a master cylinder 30. The interior of the tank body 11 is divided into a plurality of chambers including a fluid level detecting chamber 13 by partition walls 12 to minimize pulsation of hydraulic fluid F. (In FIGS. 1 to 5, the partition walls 12 are partially not shown.) The upper shell 11b has on its top a hydraulic fluid supply port 18 integral with the upper shell 11b through which hydraulic fluid F is supplied into the tank body 11. The lower shell 11a has a port 19a through which hydraulic fluid F flows between the master cylinder 30 and the reservoir tank 10, and a port 19b through which the hydraulic fluid F flows between the reservoir tank 10 and the master cylinder 30 and/or hydraulic units such as a pump. When hydraulic fluid flows into the reservoir tank through the port 19a or 19b, it passes through a filter 14 or 24 and any foreign objects such as small rubber pieces are removed.

#A brake pedal 31 is coupled to the master cylinder 30. A cap, not shown, is put on the hydraulic fluid supply port 18. By removing the cap, hydraulic fluid F can be supplied into the tank body 11.

#A fluid level sensor 16 is mounted in the hydraulic level detecting chamber 13 so as to be disposed in the lower shell 11a. The sensor 16 has a shaft 16a on which a float 15 is axially slidably mounted. According to the level of hydraulic fluid F in the tank body, the float 15 is movable by a distance t shown in FIG. 1 between the position shown by solid line in FIG. 1 and the position shown by the phantom line. The fluid level sensor 16 (see FIG. 3) senses the axial position of the float and thus the fluid level. The fluid level sensor 16 may be a proximity switch.

Facts

Application

11/177,287Filed 11 Jul 2005

Priority

JP 2004-21423522 Jul 2004

Published

US 2006/0016484 A126 Jan 2006

Granted

18 Oct 2011

Term ends

4 Sep 2027

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 785 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification9 codes

F16K 27/02
Construction of housing ; Use of materials therefor: of lift valves
B60T 11/26
Transmitting by fluid means, e.g. hydraulic: reservoirs
B60T 17/225
Devices for monitoring or checking brake systems; Signal devices: brake fluid level indicators
F16K 33/00
Floats for actuation of valves or other apparatus

Timeline

22 Jul 2004Priority claimedJP 2004-214235
11 Jul 2005Application filedUS 11/177,287
26 Jan 2006PublishedUS 2006/0016484 A1
8 Jul 2008Assigned to Advics Co., Ltd.assignment of assignor's interest
18 Oct 2011GrantedUS 8,037,898 B2
12 Oct 2026TodayWithin its term
4 Sep 2027Term endsEstimated, includes 785 days of adjustment

Reservoir tank for vehicle brake system

Life of this patent

Reservoir tank for vehicle brake system

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims5

Description2,163 words

Drawings

Classification9 codes

Life of this patent

Description2,163 words