CA1080281A - Hydraulic brake booster reserve system - Google Patents
Hydraulic brake booster reserve systemInfo
- Publication number
- CA1080281A CA1080281A CA282,745A CA282745A CA1080281A CA 1080281 A CA1080281 A CA 1080281A CA 282745 A CA282745 A CA 282745A CA 1080281 A CA1080281 A CA 1080281A
- Authority
- CA
- Canada
- Prior art keywords
- pressure
- pressure chamber
- piston
- chamber
- housing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
- B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
- B60T13/12—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid
- B60T13/14—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid using accumulators or reservoirs fed by pumps
- B60T13/142—Systems with master cylinder
- B60T13/143—Master cylinder mechanically coupled with booster
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- Engineering & Computer Science (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Braking Systems And Boosters (AREA)
Abstract
HYDRAULIC BRAKE BOOSTER RESERVE SYSTEM
ABSTRACT OF THE DISCLOSURE
A hydraulic brake booster provides a housing within which a spool valve is slidably mounted. The housing forms a pressure chamber and the spool valve is movable from a first position venting the pressure chamber to a second position, communicating the pressure chamber to a fluid pressure source as the spool valve moves toward the second position. A piston or cylindrical accumulator is also slidably mounted in the housing and moves in response to pressurized fluid in the pressure chamber to actuate braking. In order to hydraulically actuate braking when the pressure source is disabled, the piston includes a storage chamber within which pressurized fluid from the pressure chamber is stored. With the source disabled an operator actuating means moves the spool valve to the second position to close the pressure chamber to the pressure source. Further movement of the operator actuating means actuates a check valve to open the storage chamber to the pressure chamber so that pressurized fluid is communicated to the pressure chamber to move the piston for actuating braking.
ABSTRACT OF THE DISCLOSURE
A hydraulic brake booster provides a housing within which a spool valve is slidably mounted. The housing forms a pressure chamber and the spool valve is movable from a first position venting the pressure chamber to a second position, communicating the pressure chamber to a fluid pressure source as the spool valve moves toward the second position. A piston or cylindrical accumulator is also slidably mounted in the housing and moves in response to pressurized fluid in the pressure chamber to actuate braking. In order to hydraulically actuate braking when the pressure source is disabled, the piston includes a storage chamber within which pressurized fluid from the pressure chamber is stored. With the source disabled an operator actuating means moves the spool valve to the second position to close the pressure chamber to the pressure source. Further movement of the operator actuating means actuates a check valve to open the storage chamber to the pressure chamber so that pressurized fluid is communicated to the pressure chamber to move the piston for actuating braking.
Description
lV80Z~31 BACKGROUND OF THE INVENTION
It is known in prTor art brake booster to provide an accumulator to a hydraulic brake booster so that when the power source faTls stored pressurlzed fluid in the accumulator is available to asstst in actuating braklng. For example, tf the fan belt on a motor vehicle breaks, the power steering pump is disabled so that no source of fluid pressure is avaTlable to actuate braktng unless a secondary pressure source Ts pro-vided. Consequently, prior art brake boosters provide an accumulator whTch is communicated with the brake booster pressure chamber when the pressure source is disabled to actuate braking.
In vTew of the decreastng size of most motor vehicles in order to compensate for fuel consumptton, englne compartments are also diminishing.
Wlth less space for ~ountlng a hydraulic brake booster, it is advantageous to provtde a compact hydraulic brake booster for easier tnstallatton and matntenance. However, the compact booster must tnclude a secondary pres-sure source for assisting brake application when ttle main pressure source Is rendered Inoperattve.
SUMMARY OF THE IN~ENTION
The present Inventlon provtdes a hydraultc brake booster tn whtch a ptston deftnes a storage chamber for communtcatlng pressurlzed fluid theretn wlth the pressure cha~ber to assist tn effecttng a brake appltcatton durtng fatlure of the prtmary pressure source. The storage chamber ts charged with pressurtzed fluTd durtng normal brake appltcatlons.
In particular, a brake booster houstng deflnes a pressure chamber and slIdably carrles a spool valve and a ptston. An operator-controlled actuatlng means Is responsive to brake pedal movement to actuate the spool valve for communlcattng the pressure chamber wtth a pressure source so ~hat tncreaslng pressure tn the pressure chamber moves the ptston to actuate a master cyltnder for actuatlng braklng. A check valve tn the ptston communt-cates the increaslng pressure tn the pressure chamber with the storage
It is known in prTor art brake booster to provide an accumulator to a hydraulic brake booster so that when the power source faTls stored pressurlzed fluid in the accumulator is available to asstst in actuating braklng. For example, tf the fan belt on a motor vehicle breaks, the power steering pump is disabled so that no source of fluid pressure is avaTlable to actuate braktng unless a secondary pressure source Ts pro-vided. Consequently, prior art brake boosters provide an accumulator whTch is communicated with the brake booster pressure chamber when the pressure source is disabled to actuate braking.
In vTew of the decreastng size of most motor vehicles in order to compensate for fuel consumptton, englne compartments are also diminishing.
Wlth less space for ~ountlng a hydraulic brake booster, it is advantageous to provtde a compact hydraulic brake booster for easier tnstallatton and matntenance. However, the compact booster must tnclude a secondary pres-sure source for assisting brake application when ttle main pressure source Is rendered Inoperattve.
SUMMARY OF THE IN~ENTION
The present Inventlon provtdes a hydraultc brake booster tn whtch a ptston deftnes a storage chamber for communtcatlng pressurlzed fluid theretn wlth the pressure cha~ber to assist tn effecttng a brake appltcatton durtng fatlure of the prtmary pressure source. The storage chamber ts charged with pressurtzed fluTd durtng normal brake appltcatlons.
In particular, a brake booster houstng deflnes a pressure chamber and slIdably carrles a spool valve and a ptston. An operator-controlled actuatlng means Is responsive to brake pedal movement to actuate the spool valve for communlcattng the pressure chamber wtth a pressure source so ~hat tncreaslng pressure tn the pressure chamber moves the ptston to actuate a master cyltnder for actuatlng braklng. A check valve tn the ptston communt-cates the increaslng pressure tn the pressure chamber with the storage
- 2 - ~
~080Z~l chamber and retains the pressurized fluid in the storage when the pressure in the pressure chamber decreases following a brake application.
When the pressure source is disabled, the operator-controlled actuating means cooperates with the spool valve to close the pressure chamber and, subsequently; cooperates with the check valve to release the pressure in the storage chamber into the pressure chamber for urging the piston in a direction actuating the master cylinder.
As the piston in a hydraulic brake booster is re-quired in order to actuate the brake master cylinder, the provision of a storage chamber within the piston to form an accumulator optimizes the compactness of the brake booster. Therefore, installation is simplified due to the size of the unit and the unit is compatible with the small-er engine compartments resulting from smaller motor vehicles.
Thus, the present invention is defined as a hydraulic brake booster comprising: a housing defining a pressure chamber; a pressure responsive member movably disposed in the housingj the member being movable relative to the housing in response to pressure in the pressure chamber; the member defining a storage chamber; the storage chamber communicating with the pressure chamber when the pressure in the pressure chamber is insufficient to move the pressure responsive member.
DES CRIPTI ON OF ~HE DRAWINGS
Figure 1 is a schematic illustration of a vehicle hydraulic system with a hydraulic brake booster^of the present invention, shown in cross-section.
Figure 2 is an enlarged fragmentary cross-sectional view of the piston used in the hydraulic brake booster
~080Z~l chamber and retains the pressurized fluid in the storage when the pressure in the pressure chamber decreases following a brake application.
When the pressure source is disabled, the operator-controlled actuating means cooperates with the spool valve to close the pressure chamber and, subsequently; cooperates with the check valve to release the pressure in the storage chamber into the pressure chamber for urging the piston in a direction actuating the master cylinder.
As the piston in a hydraulic brake booster is re-quired in order to actuate the brake master cylinder, the provision of a storage chamber within the piston to form an accumulator optimizes the compactness of the brake booster. Therefore, installation is simplified due to the size of the unit and the unit is compatible with the small-er engine compartments resulting from smaller motor vehicles.
Thus, the present invention is defined as a hydraulic brake booster comprising: a housing defining a pressure chamber; a pressure responsive member movably disposed in the housingj the member being movable relative to the housing in response to pressure in the pressure chamber; the member defining a storage chamber; the storage chamber communicating with the pressure chamber when the pressure in the pressure chamber is insufficient to move the pressure responsive member.
DES CRIPTI ON OF ~HE DRAWINGS
Figure 1 is a schematic illustration of a vehicle hydraulic system with a hydraulic brake booster^of the present invention, shown in cross-section.
Figure 2 is an enlarged fragmentary cross-sectional view of the piston used in the hydraulic brake booster
- 3 -rw/~
108028i illustrated ln Figure 1.
DETAILED DESCRIPTION
~ eferrlng now to the drawings, the brake booster generally indicated by the numeral 10 includes a housing 12 havlng an lnlet port 14~ an outlet port 16, and a return or exhaust port 18. The inlet port 14 is communicated to the outlet or high pressure side of the vehicle power steer-ing pump 20, and the outlet port 16 is communicated to the inlet of the vehicle power steering gear 22. The exhaust 10port 18 and the outlet of the gear 22 are each connected to a reservoir (not shown) at the inlet or low pressure side of the pump 20.
The housing 12 defines first and second bores 24 ~ '~
and 26 therewithin. A piston 28 is slidably mounted in the bore 24 and is provided with :
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.i,~
108V;~
a connecttng rod 30 hhich transmits movement of the ptston 28 to a conven-tional automotlve master cylTnder (not shown) which is mounted just to the left of the houslng 12 vlewing Figure 1. Of course movement of the piston 28 to the left generates pressure in the aforementioned n1aster cylinder in the conventional manner. One end of another rod 32 Ts slidably received tn a bore 34 In the piston 28 and the opposite end of the rod 32 Ts connected to a conventlonal brake pedal (not shown) mounted in the vehicle operator s compartment. A bracket 36 is slidably mounted on the rod 32 and Is urged into engagement with a stop ring 38 by a sprtng 40.
A first pivot 42 connects one end of lever means 44 to a bracket 46 which is tntegral with the piston 28 and a second pivot 48 connects the inter-mediate portlon of the lever means 44 with the bracket 36.
A spool valve generally indicated by the numeral 50 is slidably mounted in the bore 26 and is adapted to control fluTd communicatlon Into the booster pressure chamber 52. A secondary valve 54 is slidably mounted on the end of the spool valve 56 extending into the pressure chamber 52 and a third plvot 56 connects the lever means 44 with the secondary valve 54.
A sprTng 58 yleldably urges the secondary valve 54 away from openlngs 60 in the body of the spool valve 50. Another spring 62 yieldably urges the spool valve 50 tnto a ftrst or brake-released positton deftned by the engage-ment of a stop 64 carrled on the spool valve 50 with a shoulder 66 provided on the wall of the bore 26. The second or brake fully applied posltton of the spool valve 50 is deftned by the engagement of the left hand end of the spool valve 50 with a pl~Jg 68 whtch closes the bore 26.
The spool valve 50 and houstng bore 26 tnclude cooperatlng lands and grooves such that in the ftrst posit10n illustrated in Ftgure 1 the pressure chamber 52 is vented vta openings 60 passage 88 and openings 80 to the exhaust port 18. As the spool vatve 50 moves to the second posttton wlth the left end of spool valve 50 abuttlng plug 68 the pressure chamber 52 Is communicated vla openTngs 60 passage 88 and openlngs 80 to the tnlet port 14.
10~3VZ~l The piston 28, as Tllustrated more clearly In Flgure 2, includes a plug 90 threadably engaging an open end of the plston. The plug and piston cooperate to form a storage chamber 92 located intern-~ h ally of the piston. A diaphragm gK~ slidingly engages the inner wall ofthe storage chamber 92, and is biased to the right viewing the Figures by a compresslble gas medlum on the left slde of the dtaphragm, to pres-surize the fluid content of the storage chamber.
The plug 90 defines the bore 34 which slidingly receives the rod 32. The rod 32 Is slotted at 114 to allow fluTd communtcation between the rod 32 and bore 3~. A check valve 96 is centrally disposed in the plug cooperates with bore 34 to define a passage commun7cating the storage chamber 92 with the pressure chamber 52 when the pressure in the pressure chamber is larger than the pressure in the storage chamber. A boss 112 on the Inside of plug 90 is staked at its opening to retain the ball check valve ~6 within the plug. The plug 90 also carrtes a pressure relief valve 9~ opening communication between the storage chamber and the pressure chamber when the pressure In the storage chamber Is above a predetermTned value. This rellef valve prevents bulldup of fluld pressure In the storage chambet above that whlch is sultable for actuatlng braktng. Communlcatlon between the storage and pressure chambers is also establIshed, when the pressure tn the pressure chamber is below that in the storage chamber during a brake actua-tton, by means of a projectlon 100 on the rod 32, whTch proJection engages the check valve to unseat the ball of the check valve 96.
Seal means 102 and 104 are carrTed wlthln recesses on the plug and dtaphragm, respectively, to seal the plug and piston and to slidlngly seal the diaphragm to the Inner wall of the storage chamber.
A snap ring 106 retains the dTaph agm w1thln the storage chamber and is mounted In a recess on the inner wall of the storage chamber.
MODE OF OPERATION
When the operator presses on the brake pedal, the rod 32 moves 1080~2ti 1 to the left vlewing Figures la and 2, thereby pivoting lever 44 about pTvot 42 to move the spool valve 50 to the left in the second position. In thls posi-tion the spool valve 50 communlcates the inlet port 14 with the pressure chamber 52. Increasing pressures in the pressure chamber from the inlet port communicate with the storage chamber 92 via bore 34 and check valve 96, whtle also urging the piston 28 to the left to eng~ge the connecting rod with a master cylinder for actuating braking.
If the pressure source 2û Is disconnected from the hydraulic brake booster 10 or disabled, no pressure is communlcated to the pressure chamber 52.
Moreover, no pressure is communicated to the pressure chamber 52 when the spool valve sticks. Consequently, when the operator steps on the brake pedal to shift the spool valve to the second position no movement of the plston occurs. In accordance with the inventlon, further movement of the rod 32 pivots the lever 44 to move the valve 54 to the left on the spool valve 50 to close openings 60, whereupon projection 100 on the rod 32 engages check valve 96 to communicate the storage chamber 92 on the rTght side of dia-phragm 94 with the pressure chamber 52. ThTs communication increases the pressure In the pressure chamber 52 to urge ptston 28 to the left thereby actuating braklng.
WTth the pressure source disabled or dTsconnected from the hydraullc brake booster, several brake applicatTons by the operator will exhaust the pressurlzed fluld contaTned In the storage chamber. Thereafter, brake actu-atTon proceeds as follows. SteppTng on the brake pedal moves the rod 32 to the left to engage proJectTon 100 wTth check valve 96. Because the pres-surtzed flutd Is spent in precedTng brake applTcations, no IncreasTng pres-sures are communTcated to the pressure chamber. Consequently, further rod movement Is required to actuate braklng. Such further movement pTvots lever 44 about pivat 56 on spool valve 50 to move bracket 46 to the left.
Slnce bracket 46 Ts Integral wTth pTston 28, movement of the bracket moves the ptston to operate the master cylTnder for actuatTng braklng.
~08()~81 The last-mentioned braking applicatTon, whlch proceeds without a pressure source or a stored pressurlzed fluid tn the storage chamber, results Tn a manual brake applIcatTon as the rod 32 mechanlcally urges the rod 30 in a direction actuating the master cyltnder.
Thus tt is apparent from the aforementioned descriptlon that the present invention provides a compact hydraulic brake booster wlth a piston defTning an accumulator whlch permits at least one safety braklng appllcatlon after a pressure source for the booster has been disconnected. Thereafter, with the pressure source disconnected, the operator manually actuates braking.
WhTle the invention has been described in conjunction with a speclflc embodiment thereof, ft ts evident that many alternatives, modifl-cations, and variations are included within the broad scope of the appended claims.
108028i illustrated ln Figure 1.
DETAILED DESCRIPTION
~ eferrlng now to the drawings, the brake booster generally indicated by the numeral 10 includes a housing 12 havlng an lnlet port 14~ an outlet port 16, and a return or exhaust port 18. The inlet port 14 is communicated to the outlet or high pressure side of the vehicle power steer-ing pump 20, and the outlet port 16 is communicated to the inlet of the vehicle power steering gear 22. The exhaust 10port 18 and the outlet of the gear 22 are each connected to a reservoir (not shown) at the inlet or low pressure side of the pump 20.
The housing 12 defines first and second bores 24 ~ '~
and 26 therewithin. A piston 28 is slidably mounted in the bore 24 and is provided with :
-3a-cbr/ d~
.i,~
108V;~
a connecttng rod 30 hhich transmits movement of the ptston 28 to a conven-tional automotlve master cylTnder (not shown) which is mounted just to the left of the houslng 12 vlewing Figure 1. Of course movement of the piston 28 to the left generates pressure in the aforementioned n1aster cylinder in the conventional manner. One end of another rod 32 Ts slidably received tn a bore 34 In the piston 28 and the opposite end of the rod 32 Ts connected to a conventlonal brake pedal (not shown) mounted in the vehicle operator s compartment. A bracket 36 is slidably mounted on the rod 32 and Is urged into engagement with a stop ring 38 by a sprtng 40.
A first pivot 42 connects one end of lever means 44 to a bracket 46 which is tntegral with the piston 28 and a second pivot 48 connects the inter-mediate portlon of the lever means 44 with the bracket 36.
A spool valve generally indicated by the numeral 50 is slidably mounted in the bore 26 and is adapted to control fluTd communicatlon Into the booster pressure chamber 52. A secondary valve 54 is slidably mounted on the end of the spool valve 56 extending into the pressure chamber 52 and a third plvot 56 connects the lever means 44 with the secondary valve 54.
A sprTng 58 yleldably urges the secondary valve 54 away from openlngs 60 in the body of the spool valve 50. Another spring 62 yieldably urges the spool valve 50 tnto a ftrst or brake-released positton deftned by the engage-ment of a stop 64 carrled on the spool valve 50 with a shoulder 66 provided on the wall of the bore 26. The second or brake fully applied posltton of the spool valve 50 is deftned by the engagement of the left hand end of the spool valve 50 with a pl~Jg 68 whtch closes the bore 26.
The spool valve 50 and houstng bore 26 tnclude cooperatlng lands and grooves such that in the ftrst posit10n illustrated in Ftgure 1 the pressure chamber 52 is vented vta openings 60 passage 88 and openings 80 to the exhaust port 18. As the spool vatve 50 moves to the second posttton wlth the left end of spool valve 50 abuttlng plug 68 the pressure chamber 52 Is communicated vla openTngs 60 passage 88 and openlngs 80 to the tnlet port 14.
10~3VZ~l The piston 28, as Tllustrated more clearly In Flgure 2, includes a plug 90 threadably engaging an open end of the plston. The plug and piston cooperate to form a storage chamber 92 located intern-~ h ally of the piston. A diaphragm gK~ slidingly engages the inner wall ofthe storage chamber 92, and is biased to the right viewing the Figures by a compresslble gas medlum on the left slde of the dtaphragm, to pres-surize the fluid content of the storage chamber.
The plug 90 defines the bore 34 which slidingly receives the rod 32. The rod 32 Is slotted at 114 to allow fluTd communtcation between the rod 32 and bore 3~. A check valve 96 is centrally disposed in the plug cooperates with bore 34 to define a passage commun7cating the storage chamber 92 with the pressure chamber 52 when the pressure in the pressure chamber is larger than the pressure in the storage chamber. A boss 112 on the Inside of plug 90 is staked at its opening to retain the ball check valve ~6 within the plug. The plug 90 also carrtes a pressure relief valve 9~ opening communication between the storage chamber and the pressure chamber when the pressure In the storage chamber Is above a predetermTned value. This rellef valve prevents bulldup of fluld pressure In the storage chambet above that whlch is sultable for actuatlng braktng. Communlcatlon between the storage and pressure chambers is also establIshed, when the pressure tn the pressure chamber is below that in the storage chamber during a brake actua-tton, by means of a projectlon 100 on the rod 32, whTch proJection engages the check valve to unseat the ball of the check valve 96.
Seal means 102 and 104 are carrTed wlthln recesses on the plug and dtaphragm, respectively, to seal the plug and piston and to slidlngly seal the diaphragm to the Inner wall of the storage chamber.
A snap ring 106 retains the dTaph agm w1thln the storage chamber and is mounted In a recess on the inner wall of the storage chamber.
MODE OF OPERATION
When the operator presses on the brake pedal, the rod 32 moves 1080~2ti 1 to the left vlewing Figures la and 2, thereby pivoting lever 44 about pTvot 42 to move the spool valve 50 to the left in the second position. In thls posi-tion the spool valve 50 communlcates the inlet port 14 with the pressure chamber 52. Increasing pressures in the pressure chamber from the inlet port communicate with the storage chamber 92 via bore 34 and check valve 96, whtle also urging the piston 28 to the left to eng~ge the connecting rod with a master cylinder for actuating braking.
If the pressure source 2û Is disconnected from the hydraulic brake booster 10 or disabled, no pressure is communlcated to the pressure chamber 52.
Moreover, no pressure is communicated to the pressure chamber 52 when the spool valve sticks. Consequently, when the operator steps on the brake pedal to shift the spool valve to the second position no movement of the plston occurs. In accordance with the inventlon, further movement of the rod 32 pivots the lever 44 to move the valve 54 to the left on the spool valve 50 to close openings 60, whereupon projection 100 on the rod 32 engages check valve 96 to communicate the storage chamber 92 on the rTght side of dia-phragm 94 with the pressure chamber 52. ThTs communication increases the pressure In the pressure chamber 52 to urge ptston 28 to the left thereby actuating braklng.
WTth the pressure source disabled or dTsconnected from the hydraullc brake booster, several brake applicatTons by the operator will exhaust the pressurlzed fluld contaTned In the storage chamber. Thereafter, brake actu-atTon proceeds as follows. SteppTng on the brake pedal moves the rod 32 to the left to engage proJectTon 100 wTth check valve 96. Because the pres-surtzed flutd Is spent in precedTng brake applTcations, no IncreasTng pres-sures are communTcated to the pressure chamber. Consequently, further rod movement Is required to actuate braklng. Such further movement pTvots lever 44 about pivat 56 on spool valve 50 to move bracket 46 to the left.
Slnce bracket 46 Ts Integral wTth pTston 28, movement of the bracket moves the ptston to operate the master cylTnder for actuatTng braklng.
~08()~81 The last-mentioned braking applicatTon, whlch proceeds without a pressure source or a stored pressurlzed fluid tn the storage chamber, results Tn a manual brake applIcatTon as the rod 32 mechanlcally urges the rod 30 in a direction actuating the master cyltnder.
Thus tt is apparent from the aforementioned descriptlon that the present invention provides a compact hydraulic brake booster wlth a piston defTning an accumulator whlch permits at least one safety braklng appllcatlon after a pressure source for the booster has been disconnected. Thereafter, with the pressure source disconnected, the operator manually actuates braking.
WhTle the invention has been described in conjunction with a speclflc embodiment thereof, ft ts evident that many alternatives, modifl-cations, and variations are included within the broad scope of the appended claims.
Claims (14)
1. A hydraulic brake booster comprising:
a housing defining a pressure chamber;
spool valve means cooperating with said housing to vent the pres-sure chamber when said spool valve means is in a first position and communi-cate the pressure chamber to a pressure source as said spool valve means moves to a second position;
a piston slidably mounted in said housing;
said piston being responsive to pressure within said pressure chamber to move relative to the housing to actuate braking;
said piston defining a storage chamber;
check valve means communicating the pressure chamber and the storage chamber when the pressure in the pressure chamber is above that in the storage chamber; and operator actuating means engaging the spool valve means to move the same from said first position to said second position;
said operator actuating means cooperating with the spool valve means in the second position to close communication between the pressure source and pressure chamber;
said operator actuating means also cooperating with said check valve means to open communication between the storage chamber and pressure chamber after said operator actuating means moves the spool valve to the second position and cooperates with the spool valve to close communication between the pressure source and pressure chamber.
a housing defining a pressure chamber;
spool valve means cooperating with said housing to vent the pres-sure chamber when said spool valve means is in a first position and communi-cate the pressure chamber to a pressure source as said spool valve means moves to a second position;
a piston slidably mounted in said housing;
said piston being responsive to pressure within said pressure chamber to move relative to the housing to actuate braking;
said piston defining a storage chamber;
check valve means communicating the pressure chamber and the storage chamber when the pressure in the pressure chamber is above that in the storage chamber; and operator actuating means engaging the spool valve means to move the same from said first position to said second position;
said operator actuating means cooperating with the spool valve means in the second position to close communication between the pressure source and pressure chamber;
said operator actuating means also cooperating with said check valve means to open communication between the storage chamber and pressure chamber after said operator actuating means moves the spool valve to the second position and cooperates with the spool valve to close communication between the pressure source and pressure chamber.
2. The hydraulic brake booster of claim 1, in which said piston carries a relief valve responsive to pressure within the storage chamber and venting the same to the pressure chamber when the pressure within the storage chamber is above a predetermined value.
3. The hydraulic brake booster of claim 1 in which said piston includes a plug forming a portion of said storage chamber and a relief valve is disposed in the plug.
4. The hydraulic brake booster of claim 1 in which said piston includes a plug forming a portion of said storage chamber; said plug form-ing a passage communicating the pressure chamber with the storage chamber and said check valve means is disposed in the passage.
5. The hydraulic brake booster of claim 4 in which said operator actuating means includes a portion extending into the passage and said portion is engageable with said check valve means, said operator actuating means portion including slots cooperating with the passage to communicate the pressure chamber to the storage chamber.
6. The hydraulic brake booster of claim 1 in which a diaphragm is disposed within said storage chamber and said diaphragm is biased to pressurize the storage chamber on one side of the diaphragm.
7. A hydraulic brake booster comprising:
a housing defining a pressure chamber;
a piston slidably disposed in said housing;
said piston being responsive to pressure in the pressure chamber to move relative to the housing to actuate braking;
said piston defining a storage chamber; and operator actuating means cooperating with said piston to open communication between the storage chamber and the pressure chamber when the pressure in the pressure chamber is below that required to move the piston relative to the housing when a brake application is effected.
a housing defining a pressure chamber;
a piston slidably disposed in said housing;
said piston being responsive to pressure in the pressure chamber to move relative to the housing to actuate braking;
said piston defining a storage chamber; and operator actuating means cooperating with said piston to open communication between the storage chamber and the pressure chamber when the pressure in the pressure chamber is below that required to move the piston relative to the housing when a brake application is effected.
8. The hydraulic brake booster of claim 7 in which said operator actuating means cooperates with said piston to move the piston relative to the housing when the pressure In the pressure chamber and in the storage chamber is below that required to move the piston relative to the housing to actuate braking.
9. The hydraulic brake booster of claim 7 in which said piston includes a plug forming a portion of the storage chamber and said plug carries a check valve opening communication between the storage chamber and the pressure chamber when the pressure in the pressure chamber is above that in the storage chamber.
10. The hydraulic brake booster of claim 9 in which said operator actuating means includes a projection engageable with the check valve to open communication between the storage and pressure chambers.
11. A hydraulic brake booster comprising:
a housing defining a pressure chamber;
a pressure responsive member movably disposed in said housing;
said member being movable relative to the housing in response to pressure in the pressure chamber;
said member defining a storage chamber;
said storage chamber communicating with the pressure chamber when the pressure in the pressure chamber is insufficient to move the pressure responsive member.
a housing defining a pressure chamber;
a pressure responsive member movably disposed in said housing;
said member being movable relative to the housing in response to pressure in the pressure chamber;
said member defining a storage chamber;
said storage chamber communicating with the pressure chamber when the pressure in the pressure chamber is insufficient to move the pressure responsive member.
12. In a hydraulic brake booster for a vehicle having a fluid pressure source, a housing defining a pressure chamber, a control valve movable relative to the housing to communicate the fluid pressure source with the pressure chamber during a brake application, and a piston movably disposed within a bore in the housing, the piston being completely enclosed within the housing and moving in response to the pressurized fluid within the pressure chamber to actuate braking for the vehicle, the improvement wherein the piston defines a storage chamber which is completely enclosed within the piston, said storage chamber communicating with the pressure chamber when the fluid pressure communicated from the fluid pressure source to the pressure chamber fails to move the piston.
13. In a hydraulic brake booster for a vehicle having a fluid pressure source, a housing defining a pressure chamber and movably supporting a control valve which is oper-able during a brake application to communicate the fluid pressure source with the pressure chamber, a piston movable relative to the housing in response to pressurized fluid within the pressure chamber, and an accumulator cooperating with the piston to communicate pressurized fluid stored within the accumulator to the pressure chamber when the piston fails to move relative to the housing, during a brake application the improvement wherein the accumulator is defined by and completely enclosed within the piston to compactly dispose the accumulator within the hydraulic brake booster.
14. In a hydraulic brake booster for a vehicle having a fluid pressure source, a housing substantially defining a pressure chamber and movably carrying a valve member, the valve member being movable during a brake application to communicate the pressure source with the pressure chamber, a pressure responsive member movably supported within the housing, the pressure responsive member being movable relative to the housing in response to pressurized fluid within the pressure chamber to actuate braking for the vehicle, and an accumulator which stores pressurized fluid communicated from the pressure source, the accumulator comprising with the pressure chamber when the pressure therein is insufficient to impart move-ment to the pressure responsive member during a brake applica-tion, the improvement wherein the accumulator is defined by and completely enclosed within one of the members and the accumulator is movable with the one member.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US72295676A | 1976-09-13 | 1976-09-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1080281A true CA1080281A (en) | 1980-06-24 |
Family
ID=24904162
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA282,745A Expired CA1080281A (en) | 1976-09-13 | 1977-07-14 | Hydraulic brake booster reserve system |
Country Status (11)
| Country | Link |
|---|---|
| JP (1) | JPS5335871A (en) |
| AR (1) | AR211496Q (en) |
| AU (1) | AU514146B2 (en) |
| BR (1) | BR7706042A (en) |
| CA (1) | CA1080281A (en) |
| DE (1) | DE2741164A1 (en) |
| ES (1) | ES462323A1 (en) |
| FR (1) | FR2364151A1 (en) |
| GB (1) | GB1568269A (en) |
| IT (1) | IT1084870B (en) |
| MX (1) | MX144860A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1116208A (en) * | 1978-03-13 | 1982-01-12 | Dean E. Runkle | Hydraulic brake booster and valve member |
| US4212166A (en) * | 1978-05-11 | 1980-07-15 | The Bendix Corporation | Hydraulic brake booster and relief valve therefor |
| US5185999A (en) * | 1991-10-18 | 1993-02-16 | Allied-Signal Inc. | Hydraulic brake booster and valve members |
| CN205117848U (en) * | 2015-11-19 | 2016-03-30 | 北京美高科技发展有限公司 | Cable formula static pressure seat seals instrument |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1469259A (en) * | 1966-01-13 | 1967-02-10 | Bendix Corp | Pressurized hydraulic fluid accumulator with non-return valve |
| US3695731A (en) * | 1968-02-01 | 1972-10-03 | Michael John England | Vehicle braking system |
| GB1249312A (en) * | 1968-02-01 | 1971-10-13 | Girling Ltd | Improvements in hydraulic systems, such as vehicle braking systems |
| CA983558A (en) * | 1974-02-22 | 1976-02-10 | Bendix Corporation (The) | Hydraulic brake booster with integral accumulator |
-
1977
- 1977-07-14 CA CA282,745A patent/CA1080281A/en not_active Expired
- 1977-08-19 GB GB3494577A patent/GB1568269A/en not_active Expired
- 1977-08-29 FR FR7726186A patent/FR2364151A1/en active Granted
- 1977-09-01 AU AU28473/77A patent/AU514146B2/en not_active Expired
- 1977-09-07 MX MX17049977A patent/MX144860A/en unknown
- 1977-09-09 IT IT2741377A patent/IT1084870B/en active
- 1977-09-12 BR BR7706042A patent/BR7706042A/en unknown
- 1977-09-13 AR AR26918377A patent/AR211496Q/en unknown
- 1977-09-13 JP JP10954977A patent/JPS5335871A/en active Granted
- 1977-09-13 DE DE19772741164 patent/DE2741164A1/en not_active Ceased
- 1977-09-13 ES ES462323A patent/ES462323A1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| BR7706042A (en) | 1978-06-20 |
| IT1084870B (en) | 1985-05-28 |
| JPS5335871A (en) | 1978-04-03 |
| JPS5716023B2 (en) | 1982-04-02 |
| AR211496Q (en) | 1977-12-30 |
| DE2741164A1 (en) | 1978-03-16 |
| FR2364151A1 (en) | 1978-04-07 |
| ES462323A1 (en) | 1978-05-16 |
| MX144860A (en) | 1981-11-27 |
| AU514146B2 (en) | 1981-01-29 |
| AU2847377A (en) | 1979-03-08 |
| FR2364151B1 (en) | 1980-02-01 |
| GB1568269A (en) | 1980-05-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |