US20010002978A1 - Idle volume reducing means in a piston pump for a brake system of a vehicle - Google Patents
Idle volume reducing means in a piston pump for a brake system of a vehicle Download PDFInfo
- Publication number
- US20010002978A1 US20010002978A1 US09/269,673 US26967399A US2001002978A1 US 20010002978 A1 US20010002978 A1 US 20010002978A1 US 26967399 A US26967399 A US 26967399A US 2001002978 A1 US2001002978 A1 US 2001002978A1
- Authority
- US
- United States
- Prior art keywords
- piston
- piston pump
- positive
- pump according
- retaining part
- 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.)
- Abandoned
Links
- 238000006073 displacement reaction Methods 0.000 claims abstract description 37
- 238000007789 sealing Methods 0.000 claims description 18
- 239000004033 plastic Substances 0.000 claims description 8
- 229920003023 plastic Polymers 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 3
- 230000000295 complement effect Effects 0.000 claims description 2
- 230000003247 decreasing effect Effects 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 description 9
- 239000000314 lubricant Substances 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- 239000012530 fluid Substances 0.000 description 8
- 230000006835 compression Effects 0.000 description 3
- 238000007906 compression Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 238000005086 pumping Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- 229920002430 Fibre-reinforced plastic Polymers 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000011151 fibre-reinforced plastic Substances 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
- F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
- F04B1/0404—Details or component parts
- F04B1/0421—Cylinders
-
- 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
- B60T13/16—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 pumps directly, i.e. without interposition of accumulators or reservoirs
- B60T13/168—Arrangements for pressure supply
-
- 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
- B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
- B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
- B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
- B60T8/40—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition comprising an additional fluid circuit including fluid pressurising means for modifying the pressure of the braking fluid, e.g. including wheel driven pumps for detecting a speed condition, or pumps which are controlled by means independent of the braking system
- B60T8/4031—Pump units characterised by their construction or mounting
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
- F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
- F04B1/0404—Details or component parts
- F04B1/0408—Pistons
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/10—Valves; Arrangement of valves
- F04B53/12—Valves; Arrangement of valves arranged in or on pistons
- F04B53/125—Reciprocating valves
- F04B53/126—Ball valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/14—Pistons, piston-rods or piston-rod connections
- F04B53/143—Sealing provided on the piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/14—Pistons, piston-rods or piston-rod connections
- F04B53/148—Pistons, piston-rods or piston-rod connections the piston being provided with channels which are coacting with the cylinder and are used as a distribution member for another piston-cylinder unit
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
- F04B9/02—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being mechanical
- F04B9/04—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being mechanical the means being cams, eccentrics or pin-and-slot mechanisms
- F04B9/045—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being mechanical the means being cams, eccentrics or pin-and-slot mechanisms the means being eccentrics
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2225/00—Synthetic polymers, e.g. plastics; Rubber
Definitions
- the invention relates to a piston pump as generically defined by the preamble to the main claim, which is intended in particular for a hydraulic vehicle brake system with slip control.
- One such piston pump is known for instance from German Patent Disclosure DE 44 07 978 A1.
- the known piston pump has a piston that can be driven to execute a reciprocating stroke motion. In its stroke motion, the piston decreases and increases a volume of a positive-displacement chamber of the piston pump. When the volume of the positive-displacement chamber is decreased, fluid is positively displaced; this is a pumping stroke of the piston pump. When the volume of the positive-displacement chamber is increased, fluid is aspirated, which is an intake stroke of the piston pump.
- the piston pump of the invention having the characteristics of the main claim has a positive-displacement body, which is disposed in the positive-displacement chamber.
- This positive-displacement body decreases an available volume of the positive-displacement chamber and is embodied in particular such that a residual or idle volume remaining at the end of the pumping stroke is as small as possible.
- the piston pump of the invention is intended in particular as a pump in a brake system of a vehicle and is used to control the pressure in wheel brake cylinders.
- ABS the abbreviations ABS, ASR, FDR and EHB are used for such brake systems.
- the pump serves for instance to return brake fluid from a wheel brake cylinder or a plurality of wheel brake cylinders to a master cylinder (ABS) and/or to pump brake fluid out of a supply container into a wheel brake cylinder or a plurality of wheel brake cylinders (ASR or FDR or EHB).
- a brake system with wheel slip control ABS or ASR
- a brake system serving as a steering aid FDR
- EHB electrohydraulic brake system
- the pump is needed.
- ABS or ASR wheel slip control
- locking of the wheels of the vehicle during a braking event involving strong pressure on the brake pedal (ABS) and/or spinning of the driven wheels of the vehicle in the event of strong pressure on the gas pedal (ASR) can for instance be prevented.
- a brake pressure is built up in one or more wheel brake cylinders independently of an actuation of the brake pedal or gas pedal, for instance to prevent the vehicle from breaking out of the track desired by the driver.
- the pump can also be used in an electrohydraulic brake system (EHB), in which the pump pumps the brake fluid into the wheel brake cylinder or wheel brake cylinders if an electric brake pedal sensor detects an actuation of the brake pedal, or in which the pump is used to fill a reservoir of the brake system.
- EHB electrohydraulic brake system
- FIGS. 1 and 2 shows axial sections through two exemplary embodiments of piston pumps of the invention
- FIG. 3 is an end view of a retaining part of the piston pump shown in FIG. 2
- FIG. 4 shows a modification of the piston pump shown in FIG. 2.
- the piston pump of the invention shown in FIG. 1 and identified overall by reference numeral 10 has a boltlike piston 12 , which is axially displaceable guided in a plastic bush 14 .
- the bush 14 is inserted into a hydraulic block of a hydraulic vehicle brake system, not otherwise shown, that forms a pump housing 16 .
- Other hydraulic components, such as magnet valves, not shown, are inserted and hydraulically connected to one another and to the piston pump 10 in the hydraulic block, of which the drawing shows only a fraction surrounding the piston pump 10 .
- a face end of the bush 14 is closed with a disklike closure part 18 , which is fixed by a caulking 20 of the pump housing 16 .
- the bush 14 , piston 12 and closure part 18 enclose a positive-displacement chamber 22 of the piston pump 10 .
- a helical compression spring is disposed as a piston restoring spring 24 in the positive-displacement chamber 22 ; it is supported on the closure part 18 and presses the piston 12 against a circumferential face of an eccentric element 26 , which can be driven to rotate by an electric motor and by means of which the piston 12 can be driven in a manner known per se to execute a reciprocating stroke motion in the bush 14 .
- two spring-loaded check valves 28 are disposed outside the bush 14 , in the hydraulic block forming the pump housing 16 , and they are shown symbolically in FIG. 1.
- the check valves 28 communicate with the positive-displacement chamber via a radial bore 30 in the bush 14 .
- a positive-displacement body 32 is located in the interior of the piston restoring spring 24 and largely fills up the interior of the piston restoring spring 24 .
- the positive-displacement body 32 is like a tang and protrudes integrally from the closure part 18 .
- the positive-displacement body 32 decreases the available volume in the positive-displacement chamber 22 for fluid that can be pumped by the piston pump 10 , and in particular reduces the residual volume or so-called idle volume available in the positive-displacement chamber 22 at the end of a pumping stroke, when the piston 22 assumes its position thrust farthest into the bush 14 , to a minimum. This improves the efficiency of the piston pump 10 .
- the wire comprising the piston restoring spring has a rectangular coil cross section also contributes to minimizing the idle volume.
- other cross sections may also be chosen, such as parallelogram- or gable-shaped coil cross sections, whose coil faces oriented toward one another are virtually complementary, in order to reduce a gap width between spring coils and thus to reduce the idle volume when the piston restoring spring 24 is compressed.
- the piston restoring spring 24 fills up an annular chamber between the positive-displacement body 32 and the bush 14 extensively.
- the positive-displacement body 32 can also be provided as a tanglike extension on the piston 12 and can extend (not shown) in the interior of the piston restoring spring 24 .
- the piston pump 34 of the invention is inserted into a pump housing 36 , which is formed by a hydraulic block of a hydraulic vehicle brake system not otherwise shown.
- Other hydraulic components such as magnet valves and the like, are inserted into the hydraulic block, of which the drawing for the sake of simplicity shows only a fragment surrounding the piston pump 10 , and are hydraulically connected to one another and to the piston pump 34 therein.
- the piston pump 34 has a bush 38 with a bush bottom 40 integral with it that is press-fitted into a cylinder bore 42 . By means of a crimp 44 , a cylindrical closure plug 46 is mounted on the bush bottom 40 .
- the closure plug 46 is fixed in the pump housing 36 by a caulking 48 and closes off one end of the cylinder bore 42 in pressure-tight fashion.
- a check valve as an outlet valve 52 is inserted into a blind bore 50 of the closure plug 46 ; as its valve closing body, this valve has a valve ball 54 , which is pressed by a helical compression spring as the valve closing spring 56 against a conical valve seat 58 , which is embodied at an orifice of an axial through hole 60 in the bush bottom 40 .
- An outlet is effected through a radial outlet bore 62 in the closure plug 46 , which communicates with an outlet bore 64 in the pump housing 36 .
- a piston 66 of the piston pump 34 of the invention is embodied as a composite part, with a steel core 68 whose circumference has a lubricant jacket 70 of plastic spray-coated onto it.
- a fiber-reinforced plastic with approximately 15% carbon fibers and with teflon components that lend the lubricant jacket 70 good sliding properties is for instance suitable.
- the piston 66 With its lubricant jacket 70 , the piston 66 is guided slidingly displaceably in the axial direction in the cylinder bore 42 or in the bush 40 .
- An end face of the steel core 68 of the piston 66 that is remote from the bush bottom 40 and protrudes from the bush 38 is bare; that is, it is not covered by the lubricant jacket 70 .
- This end face of the steel core 68 forms a slide face 72 , with which the piston 66 is pressed by a piston restoring spring 74 against a circumference of an eccentric element 76 which can be driven to rotate by an electric motor, and with which the piston can be driven to execute an axially reciprocating stroke motion.
- the slide face 72 is embodied in low-wearing fashion by the use of a low-wear material for the steel core 68 , or by hardening the steel core 68 .
- the steel core 68 is in terms of its shape a very easily made, substantially cylindrical part.
- the lubricant jacket 70 surrounds the circumference of the steel core 68 with a hollow-cylindrical portion 78 ; it continues, lengthening the steel core 68 or the piston 66 , on into the bush 38 on a face end of the steel core 68 remote from the eccentric element 76 .
- the portion 80 of the lubricant jacket 70 that lengthens the piston 66 has a transverse hole 82 , which passes through an axial blind bore 84 that is also made in the portion 80 of the lubricant jacket 70 that lengthens the piston 66 .
- the blind bore 84 widens, forming a conical valve seat 86 , and discharges at a face end of the piston 66 toward the bush bottom 40 .
- a check valve in the form of an inlet valve 88 is inserted into the widened part of the blind bore 84 and has a valve ball 90 as its valve closing body, which is pressed against the valve seat 86 by a helical compression spring as the valve closing spring 92 .
- the transverse hole 82 in the piston 66 communicates through a cylindrical filter screen 94 , which is mounted on a open face end of the bush 38 , with an inlet conduit 96 , which is made radially to the piston pump 34 in the pump housing 36 .
- the valve closing spring 92 is supported on a retaining part 98 , which is mounted on the face end of the piston 66 toward the bush bottom 40 .
- the retaining part 98 has a rim 100 in the form of a perforated disk, which is pressed by the piston restoring spring 74 against the face end, toward this rim, of the piston 66 , and as a result the retaining part 98 is held on the piston 66 .
- the retaining part 98 is shown in an end view, seen from the direction of the piston 66 , in FIG. 3.
- Four angled retaining ribs 102 protrude from a side remote from the piston 66 and are integral with the rim 100 in the form of the perforated disk.
- the retaining ribs 102 retain a cylindrical positive-displacement body 104 , which is integral with them and protrudes coaxially through the perforated-disk rim 100 of the retaining part 98 .
- An annular interstice exists between the positive-displacement body 104 and the perforated-disk rim 100 , so that fluid flowing through the inlet valve 88 into the piston pump 34 can flow through the perforated-disk rim 100 and between the retaining ribs 102 on into a positive-displacement chamber 106 of the piston pump 34 .
- the valve closing spring 92 which is supported on the retaining ribs 102 of the retaining part 98 , like the piston restoring spring 74 has a rectangular coil cross section.
- the rectangular coil cross section of these two springs 74 , 92 like the positive-displacement body 104 , serves to reduce a volume of the positive-displacement chamber 106 of the piston pump 34 that is available to a fluid that can be pumped by the piston pump 34 .
- the idle volume of the positive-displacement chamber 106 which remains when the piston 66 has been thrust maximally inward into the bush 38 , is reduced by the positive-displacement body 104 and the springs 74 , 92 with their rectangular coil cross sections, thus increasing the efficiency of the piston pump 34 of the invention.
- the positive-displacement body 104 of the piston pump 34 shown in FIG. 2 like the positive-displacement body 32 of the piston pump 10 shown in FIG. 1, can be embodied such that it maximally fills up the idle volume in the positive-displacement chamber 106 and thus reduces the idle volume to a minimum and increases the efficiency of the piston pump 34 .
- the retaining part 98 has four centering prongs 106 , integral with it and protruding inward into the blind bore 84 from its perforated-disk rim 100 , which hold the retaining part 98 coaxially on the piston 66 .
- the centering prongs 108 have a press fit in the blind bore 84 ; that is, the retaining part 98 is joined by frictional engagement to the piston 66 by means of a clamping connection.
- connection of the retaining part 98 with the piston 66 serves to keep the retaining part 98 on the piston 66 , counter to the force of the valve closing spring 92 , until the piston has been inserted into the bush 38 and the retaining part 98 is held on the piston 66 by the piston restoring spring 74 .
- Joining the retaining part 98 to the piston 66 can for instance also be done by positive engagement, by means of a snap or detent connection, known per se, or by material engagement, such as adhesive bonding.
- the positive-displacement body 104 defines an opening stroke of the valve ball 90 of the inlet valve 88 and forms a valve stroke limiter.
- This valve stroke limiter reduces a force with which the valve ball 90 strikes the valve seat 86 upon closure of the inlet valve 88 and thereby reduces wear to the valve seat 86 . This is especially important whenever the valve seat 86 is shaped from a soft material. As a result, in a valve seat 86 that is shaped from plastic as in the exemplary embodiment shown, a long service life is attained. Since the positive-displacement body 104 forming the valve stroke limiter is of plastic, the valve stroke limiter can be made to more precise size than a valve stroke limiter made for instance as a deep-drawn sheet-metal part.
- the centering prong 108 aligns the retaining part 98 in exact alignment with the blind bore 84 and the valve seat 86 in the piston 66 , and the retaining part 98 centers the valve closing spring 92 , the valve ball 90 is also guided in alignment with the valve seat 86 when the inlet valve 88 is opened.
- the retaining part 98 at the same time forms a guide and sealing element for the piston 66 of the piston pump 34 of the invention:
- the retaining part 98 has a low, hollow-cylindrical rim 110 , which protrudes a short distance into an annular interstice between the piston 66 and the bush 38 and is integral with the perforated-disk rim 100 on the circumference of the piston 66 .
- This hollow-cylindrical rim 110 and a circumferential edge of the perforated-disk rim 100 of the retaining part 98 guide the piston 66 in the bush 38 .
- an encompassing sealing lip 112 protrudes integrally from the perforated-disk rim 100 of the retaining part 98 .
- the sealing lip 112 is also integral with the retaining part 98 .
- a spreader ring 114 with a conical spreader face 116 on its circumference is located between the piston restoring spring 74 and the sealing lip 112 of the retaining part 98 .
- the spreader ring 114 is pressed axially by the piston restoring spring 74 against an approximately hollow-conical inside face 118 of the sealing lip 112 and in this way spreads the sealing lip 112 radially open and presses it into sealing contact against an inner wall of the bush 38 .
- the piston restoring spring 74 assures a durable elastic spreading behavior of the sealing lip 112 and thus a durably reliable sealing of the piston 66 in the bush 38 .
- the spreading force with which the sealing lip 112 is pressed against the inner wall of the bush 38 can be adjusted.
- the retaining part 98 comprises the same plastic as the lubricant jacket 70 ; it is low-wear and has good sliding properties.
- the plastic retaining part 98 can be made inexpensively.
- the piston pump 120 shown in FIG. 4 is a modification according to the invention of the piston pump 34 shown in FIG. 2.
- the retaining part 98 of the piston pump 120 shown in FIG. 4 has no sealing lip and no hollow-cylindrical rim for guiding the piston.
- the guidance of the piston 66 in the bush 38 is effected directly at the outer circumference 122 of the piston 66 .
- a rubber sealing ring 124 is placed on an annular shoulder 126 of the piston 66 , where the piston 66 narrows toward its end located inside the bush 38 .
- the perforated-disk rim 100 of the retaining part 98 holds the sealing ring 124 axially on the piston 66 .
- the sealing ring 124 can be slipped on to the annular shoulder 126 before the retaining part 98 is joined to the piston 66 . This makes it substantially easier to join the sealing ring 124 to the piston 66 .
- the piston pump 120 shown in FIG. 4 is embodied identically and functions in the same way as the piston pump 34 shown in FIG. 2. To avoid repetition, reference is made to the description of FIG. 2. Identical components are identified by the same reference numerals.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Transportation (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Details Of Reciprocating Pumps (AREA)
Abstract
Description
- The invention relates to a piston pump as generically defined by the preamble to the main claim, which is intended in particular for a hydraulic vehicle brake system with slip control.
- One such piston pump is known for instance from German
Patent Disclosure DE 44 07 978 A1. The known piston pump has a piston that can be driven to execute a reciprocating stroke motion. In its stroke motion, the piston decreases and increases a volume of a positive-displacement chamber of the piston pump. When the volume of the positive-displacement chamber is decreased, fluid is positively displaced; this is a pumping stroke of the piston pump. When the volume of the positive-displacement chamber is increased, fluid is aspirated, which is an intake stroke of the piston pump. - The piston pump of the invention having the characteristics of the main claim has a positive-displacement body, which is disposed in the positive-displacement chamber. This positive-displacement body decreases an available volume of the positive-displacement chamber and is embodied in particular such that a residual or idle volume remaining at the end of the pumping stroke is as small as possible.
- This improves the efficiency of the piston pump of the invention.
- The piston pump of the invention is intended in particular as a pump in a brake system of a vehicle and is used to control the pressure in wheel brake cylinders. Depending on the type of brake system, the abbreviations ABS, ASR, FDR and EHB are used for such brake systems. In the brake system, the pump serves for instance to return brake fluid from a wheel brake cylinder or a plurality of wheel brake cylinders to a master cylinder (ABS) and/or to pump brake fluid out of a supply container into a wheel brake cylinder or a plurality of wheel brake cylinders (ASR or FDR or EHB). In a brake system with wheel slip control (ABS or ASR) and/or a brake system serving as a steering aid (FDR) and/or an electrohydraulic brake system (EHB), the pump is needed. With the wheel slip control (ABS or ASR), locking of the wheels of the vehicle during a braking event involving strong pressure on the brake pedal (ABS) and/or spinning of the driven wheels of the vehicle in the event of strong pressure on the gas pedal (ASR) can for instance be prevented. In a brake system serving as a steering aid (FDR), a brake pressure is built up in one or more wheel brake cylinders independently of an actuation of the brake pedal or gas pedal, for instance to prevent the vehicle from breaking out of the track desired by the driver. The pump can also be used in an electrohydraulic brake system (EHB), in which the pump pumps the brake fluid into the wheel brake cylinder or wheel brake cylinders if an electric brake pedal sensor detects an actuation of the brake pedal, or in which the pump is used to fill a reservoir of the brake system.
- Advantageous features and refinements of the invention defined by the main claim are the subject of the dependent claims.
- The invention will be described in further detail below in terms of two exemplary embodiments shown in the drawing. FIGS. 1 and 2 shows axial sections through two exemplary embodiments of piston pumps of the invention; FIG. 3 is an end view of a retaining part of the piston pump shown in FIG. 2; and FIG. 4 shows a modification of the piston pump shown in FIG. 2.
- The piston pump of the invention shown in FIG. 1 and identified overall by
reference numeral 10 has aboltlike piston 12, which is axially displaceable guided in aplastic bush 14. Thebush 14 is inserted into a hydraulic block of a hydraulic vehicle brake system, not otherwise shown, that forms apump housing 16. Other hydraulic components, such as magnet valves, not shown, are inserted and hydraulically connected to one another and to thepiston pump 10 in the hydraulic block, of which the drawing shows only a fraction surrounding thepiston pump 10. - A face end of the
bush 14 is closed with adisklike closure part 18, which is fixed by a caulking 20 of thepump housing 16. Thebush 14,piston 12 andclosure part 18 enclose a positive-displacement chamber 22 of thepiston pump 10. A helical compression spring is disposed as apiston restoring spring 24 in the positive-displacement chamber 22; it is supported on theclosure part 18 and presses thepiston 12 against a circumferential face of aneccentric element 26, which can be driven to rotate by an electric motor and by means of which thepiston 12 can be driven in a manner known per se to execute a reciprocating stroke motion in thebush 14. - As the inlet and outlet valves, two spring-loaded
check valves 28 are disposed outside thebush 14, in the hydraulic block forming thepump housing 16, and they are shown symbolically in FIG. 1. Thecheck valves 28 communicate with the positive-displacement chamber via aradial bore 30 in thebush 14. - A positive-
displacement body 32 is located in the interior of thepiston restoring spring 24 and largely fills up the interior of thepiston restoring spring 24. The positive-displacement body 32 is like a tang and protrudes integrally from theclosure part 18. The positive-displacement body 32 decreases the available volume in the positive-displacement chamber 22 for fluid that can be pumped by thepiston pump 10, and in particular reduces the residual volume or so-called idle volume available in the positive-displacement chamber 22 at the end of a pumping stroke, when thepiston 22 assumes its position thrust farthest into thebush 14, to a minimum. This improves the efficiency of thepiston pump 10. The fact that the wire comprising the piston restoring spring has a rectangular coil cross section also contributes to minimizing the idle volume. Instead of a rectangular coil cross section, other cross sections may also be chosen, such as parallelogram- or gable-shaped coil cross sections, whose coil faces oriented toward one another are virtually complementary, in order to reduce a gap width between spring coils and thus to reduce the idle volume when thepiston restoring spring 24 is compressed. Thepiston restoring spring 24 fills up an annular chamber between the positive-displacement body 32 and thebush 14 extensively. The positive-displacement body 32 can also be provided as a tanglike extension on thepiston 12 and can extend (not shown) in the interior of thepiston restoring spring 24. - The
piston pump 34 of the invention, shown in FIG. 2, is inserted into apump housing 36, which is formed by a hydraulic block of a hydraulic vehicle brake system not otherwise shown. Other hydraulic components, such as magnet valves and the like, are inserted into the hydraulic block, of which the drawing for the sake of simplicity shows only a fragment surrounding thepiston pump 10, and are hydraulically connected to one another and to thepiston pump 34 therein. Thepiston pump 34 has abush 38 with abush bottom 40 integral with it that is press-fitted into acylinder bore 42. By means of acrimp 44, acylindrical closure plug 46 is mounted on thebush bottom 40. Theclosure plug 46 is fixed in thepump housing 36 by a caulking 48 and closes off one end of the cylinder bore 42 in pressure-tight fashion. A check valve as anoutlet valve 52 is inserted into ablind bore 50 of theclosure plug 46; as its valve closing body, this valve has avalve ball 54, which is pressed by a helical compression spring as thevalve closing spring 56 against aconical valve seat 58, which is embodied at an orifice of an axial throughhole 60 in thebush bottom 40. An outlet is effected through a radial outlet bore 62 in theclosure plug 46, which communicates with an outlet bore 64 in thepump housing 36. - A
piston 66 of thepiston pump 34 of the invention is embodied as a composite part, with asteel core 68 whose circumference has alubricant jacket 70 of plastic spray-coated onto it. As the plastic for the lubricant jacket, a fiber-reinforced plastic with approximately 15% carbon fibers and with teflon components that lend thelubricant jacket 70 good sliding properties is for instance suitable. With itslubricant jacket 70, thepiston 66 is guided slidingly displaceably in the axial direction in the cylinder bore 42 or in thebush 40. - An end face of the
steel core 68 of thepiston 66 that is remote from thebush bottom 40 and protrudes from thebush 38 is bare; that is, it is not covered by thelubricant jacket 70. This end face of thesteel core 68 forms aslide face 72, with which thepiston 66 is pressed by apiston restoring spring 74 against a circumference of aneccentric element 76 which can be driven to rotate by an electric motor, and with which the piston can be driven to execute an axially reciprocating stroke motion. Theslide face 72 is embodied in low-wearing fashion by the use of a low-wear material for thesteel core 68, or by hardening thesteel core 68. - The
steel core 68 is in terms of its shape a very easily made, substantially cylindrical part. Thelubricant jacket 70 surrounds the circumference of thesteel core 68 with a hollow-cylindrical portion 78; it continues, lengthening thesteel core 68 or thepiston 66, on into thebush 38 on a face end of thesteel core 68 remote from theeccentric element 76. Theportion 80 of thelubricant jacket 70 that lengthens thepiston 66 has atransverse hole 82, which passes through an axialblind bore 84 that is also made in theportion 80 of thelubricant jacket 70 that lengthens thepiston 66. The blind bore 84 widens, forming aconical valve seat 86, and discharges at a face end of thepiston 66 toward thebush bottom 40. A check valve in the form of aninlet valve 88 is inserted into the widened part of theblind bore 84 and has avalve ball 90 as its valve closing body, which is pressed against thevalve seat 86 by a helical compression spring as thevalve closing spring 92. Thetransverse hole 82 in thepiston 66 communicates through acylindrical filter screen 94, which is mounted on a open face end of thebush 38, with aninlet conduit 96, which is made radially to thepiston pump 34 in thepump housing 36. Thevalve closing spring 92 is supported on aretaining part 98, which is mounted on the face end of thepiston 66 toward thebush bottom 40. Theretaining part 98 has arim 100 in the form of a perforated disk, which is pressed by thepiston restoring spring 74 against the face end, toward this rim, of thepiston 66, and as a result theretaining part 98 is held on thepiston 66. Theretaining part 98 is shown in an end view, seen from the direction of thepiston 66, in FIG. 3. Fourangled retaining ribs 102 protrude from a side remote from thepiston 66 and are integral with therim 100 in the form of the perforated disk. Theretaining ribs 102 retain a cylindrical positive-displacement body 104, which is integral with them and protrudes coaxially through the perforated-disk rim 100 of theretaining part 98. An annular interstice exists between the positive-displacement body 104 and the perforated-disk rim 100, so that fluid flowing through theinlet valve 88 into thepiston pump 34 can flow through the perforated-disk rim 100 and between theretaining ribs 102 on into a positive-displacement chamber 106 of thepiston pump 34. - The
valve closing spring 92, which is supported on the retainingribs 102 of the retainingpart 98, like thepiston restoring spring 74 has a rectangular coil cross section. The rectangular coil cross section of these twosprings displacement body 104, serves to reduce a volume of the positive-displacement chamber 106 of thepiston pump 34 that is available to a fluid that can be pumped by thepiston pump 34. In particular, the idle volume of the positive-displacement chamber 106, which remains when thepiston 66 has been thrust maximally inward into thebush 38, is reduced by the positive-displacement body 104 and thesprings piston pump 34 of the invention. The positive-displacement body 104 of thepiston pump 34 shown in FIG. 2, like the positive-displacement body 32 of thepiston pump 10 shown in FIG. 1, can be embodied such that it maximally fills up the idle volume in the positive-displacement chamber 106 and thus reduces the idle volume to a minimum and increases the efficiency of thepiston pump 34. - In the extension of the retaining
ribs 102, the retainingpart 98 has four centeringprongs 106, integral with it and protruding inward into the blind bore 84 from its perforated-disk rim 100, which hold the retainingpart 98 coaxially on thepiston 66. In the exemplary embodiment shown, the centeringprongs 108 have a press fit in the blind bore 84; that is, the retainingpart 98 is joined by frictional engagement to thepiston 66 by means of a clamping connection. The connection of the retainingpart 98 with thepiston 66 serves to keep the retainingpart 98 on thepiston 66, counter to the force of thevalve closing spring 92, until the piston has been inserted into thebush 38 and the retainingpart 98 is held on thepiston 66 by thepiston restoring spring 74. Joining the retainingpart 98 to thepiston 66 can for instance also be done by positive engagement, by means of a snap or detent connection, known per se, or by material engagement, such as adhesive bonding. - The positive-
displacement body 104 defines an opening stroke of thevalve ball 90 of theinlet valve 88 and forms a valve stroke limiter. This valve stroke limiter reduces a force with which thevalve ball 90 strikes thevalve seat 86 upon closure of theinlet valve 88 and thereby reduces wear to thevalve seat 86. This is especially important whenever thevalve seat 86 is shaped from a soft material. As a result, in avalve seat 86 that is shaped from plastic as in the exemplary embodiment shown, a long service life is attained. Since the positive-displacement body 104 forming the valve stroke limiter is of plastic, the valve stroke limiter can be made to more precise size than a valve stroke limiter made for instance as a deep-drawn sheet-metal part. - Since the centering
prong 108 aligns the retainingpart 98 in exact alignment with the blind bore 84 and thevalve seat 86 in thepiston 66, and the retainingpart 98 centers thevalve closing spring 92, thevalve ball 90 is also guided in alignment with thevalve seat 86 when theinlet valve 88 is opened. - The retaining
part 98 at the same time forms a guide and sealing element for thepiston 66 of thepiston pump 34 of the invention: The retainingpart 98 has a low, hollow-cylindrical rim 110, which protrudes a short distance into an annular interstice between thepiston 66 and thebush 38 and is integral with the perforated-disk rim 100 on the circumference of thepiston 66. This hollow-cylindrical rim 110 and a circumferential edge of the perforated-disk rim 100 of the retainingpart 98 guide thepiston 66 in thebush 38. Under the other side from the hollow-cylindrical rim 110, that its, away from thepiston 66, an encompassing sealinglip 112 protrudes integrally from the perforated-disk rim 100 of the retainingpart 98. The sealinglip 112 is also integral with the retainingpart 98. Aspreader ring 114 with aconical spreader face 116 on its circumference is located between thepiston restoring spring 74 and the sealinglip 112 of the retainingpart 98. Thespreader ring 114 is pressed axially by thepiston restoring spring 74 against an approximately hollow-conicalinside face 118 of the sealinglip 112 and in this way spreads the sealinglip 112 radially open and presses it into sealing contact against an inner wall of thebush 38. Via thespreader ring 114, thepiston restoring spring 74 assures a durable elastic spreading behavior of the sealinglip 112 and thus a durably reliable sealing of thepiston 66 in thebush 38. Via the cone angles of thespreader face 116 of thespreader ring 114 and of theinside face 118 of the sealinglip 112, the spreading force with which the sealinglip 112 is pressed against the inner wall of thebush 38 can be adjusted. The retainingpart 98 comprises the same plastic as thelubricant jacket 70; it is low-wear and has good sliding properties. Theplastic retaining part 98 can be made inexpensively. - Another advantage of the retaining
part 98 mounted on one face end of thepiston 66 is that it protects this face end of the piston against damage before and during the insertion of thepiston 66 into thebush 38. Thepiston pump 120 shown in FIG. 4 is a modification according to the invention of thepiston pump 34 shown in FIG. 2. The retainingpart 98 of thepiston pump 120 shown in FIG. 4 has no sealing lip and no hollow-cylindrical rim for guiding the piston. The guidance of thepiston 66 in thebush 38 is effected directly at theouter circumference 122 of thepiston 66. For sealing off thepiston 66 in thebush 68, arubber sealing ring 124 is placed on anannular shoulder 126 of thepiston 66, where thepiston 66 narrows toward its end located inside thebush 38. The perforated-disk rim 100 of the retainingpart 98 holds the sealingring 124 axially on thepiston 66. The sealingring 124 can be slipped on to theannular shoulder 126 before the retainingpart 98 is joined to thepiston 66. This makes it substantially easier to join thesealing ring 124 to thepiston 66. Otherwise, thepiston pump 120 shown in FIG. 4 is embodied identically and functions in the same way as thepiston pump 34 shown in FIG. 2. To avoid repetition, reference is made to the description of FIG. 2. Identical components are identified by the same reference numerals.
Claims (14)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19732811 | 1997-07-30 | ||
DE197328113 | 1997-07-30 | ||
DE19747850A DE19747850A1 (en) | 1997-07-30 | 1997-10-30 | Piston pump |
Publications (1)
Publication Number | Publication Date |
---|---|
US20010002978A1 true US20010002978A1 (en) | 2001-06-07 |
Family
ID=26038685
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/269,673 Abandoned US20010002978A1 (en) | 1997-07-30 | 1998-07-08 | Idle volume reducing means in a piston pump for a brake system of a vehicle |
Country Status (5)
Country | Link |
---|---|
US (1) | US20010002978A1 (en) |
EP (1) | EP0935711A1 (en) |
JP (1) | JP2001501282A (en) |
DE (1) | DE19747850A1 (en) |
WO (1) | WO1999006704A1 (en) |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1275848A1 (en) * | 2001-07-13 | 2003-01-15 | Robert Bosch Gmbh | Fuel pump for a fuel system of an internal combustion engine |
US6652245B2 (en) * | 2000-03-28 | 2003-11-25 | Robert Bosch Gmbh | Piston pump for hydraulic vehicle brake system |
WO2007009664A1 (en) * | 2005-07-21 | 2007-01-25 | Ks Gleitlager Gmbh | Cam ring for an injection pump |
US20080031754A1 (en) * | 2006-08-07 | 2008-02-07 | Tomoo Harada | Piston Pump |
US20080226479A1 (en) * | 2005-09-06 | 2008-09-18 | Wolfgang Schuller | Piston Pump With Improved Piston |
US20080310971A1 (en) * | 2007-06-18 | 2008-12-18 | Tomoo Harada | Piston pump |
US20090185924A1 (en) * | 2006-06-22 | 2009-07-23 | Andre Bollwerk | Piston pump |
US20090220363A1 (en) * | 2006-06-27 | 2009-09-03 | Wolfgang Schuller | Piston pump for a vehicle brake system with a sealing element |
US20100232998A1 (en) * | 2007-10-04 | 2010-09-16 | Josef Hipp | Piston pump for delivering a fluid, and associated brake system |
US20100232994A1 (en) * | 2007-10-04 | 2010-09-16 | Beate Schumann | Piston pump for delivering a fluid, and associated brake system |
US20100247358A1 (en) * | 2007-11-06 | 2010-09-30 | Harald Hermann | Plastic element, piston pump, and assembly method |
US20100284841A1 (en) * | 2007-10-04 | 2010-11-11 | Heiko Jahn | Piston pump for delivering a fluid, and associated brake system |
US20100310395A1 (en) * | 2006-10-17 | 2010-12-09 | Oliver Schmautz | Pump for a vehicle brake system having a valve |
FR2963953A1 (en) * | 2010-08-19 | 2012-02-24 | Bosch Gmbh Robert | PISTON PUMP AND METHOD OF MAKING SUCH A PUMP |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19924774A1 (en) * | 1999-05-29 | 2000-11-30 | Bosch Gmbh Robert | Piston pump |
DE10023849B4 (en) * | 2000-05-16 | 2005-11-17 | Brueninghaus Hydromatik Gmbh | Piston engine with displaceably mounted in guide bushes of a cylinder drum piston and guide bushing for such a piston engine |
WO2004028878A1 (en) * | 2002-09-24 | 2004-04-08 | Continental Teves Ag & Co. Ohg | Supply device |
DE102006010674A1 (en) * | 2005-09-14 | 2007-03-15 | Continental Teves Ag & Co. Ohg | Piston pump for use in motor vehicle, has hub with structure that produces force directed to piston axis, where structure causes elastic deformation of body for strengthened and dosed seal contact pressure between piston and cylinder |
DE102006048902A1 (en) * | 2006-10-17 | 2008-04-30 | Robert Bosch Gmbh | Piston pump for a vehicle brake system with a piston rod |
DE102007008261A1 (en) * | 2007-02-20 | 2008-08-21 | Robert Bosch Gmbh | High-pressure pump for conveying fuel with an improved guidance of the pump piston |
DE102007054097A1 (en) * | 2007-11-13 | 2009-05-14 | Robert Bosch Gmbh | Pump element, hydraulic block with pump element and mounting method |
DE102009046313A1 (en) * | 2009-11-03 | 2011-05-05 | Robert Bosch Gmbh | Piston arrangement for piston pump of vehicle brake system, comprises piston, return spring, which is linked in axial direction of piston, and spring seat arranged at piston for return spring |
DE102012207000A1 (en) * | 2012-04-27 | 2013-10-31 | Continental Teves Ag & Co. Ohg | piston pump |
DE102017212498A1 (en) * | 2017-07-20 | 2019-01-24 | Robert Bosch Gmbh | Piston pump, in particular high-pressure fuel pump for an internal combustion engine |
CN107816432B (en) * | 2017-09-30 | 2019-11-19 | 简式国际汽车设计(北京)有限公司 | A kind of plunger pump |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3928375C2 (en) * | 1989-08-28 | 1998-02-26 | Teves Gmbh Alfred | Piston pump |
DE4133391A1 (en) * | 1991-10-09 | 1993-04-15 | Bosch Gmbh Robert | Seat valve for slip-controlled brake - has valve closure of wrought aluminium alloy, which is closed by valve closing force |
DE4425402A1 (en) * | 1993-08-06 | 1996-04-04 | Teves Gmbh Alfred | Hydraulic pump for hydraulic brake system |
DE9319462U1 (en) * | 1993-12-17 | 1995-04-27 | Lucas Ind Plc | Piston pump for pumping hydraulic fluid in an anti-lock vehicle brake system |
DE4407978C2 (en) | 1994-03-10 | 2002-11-07 | Continental Teves Ag & Co Ohg | piston pump |
JPH10246178A (en) * | 1997-03-03 | 1998-09-14 | Aisin Seiki Co Ltd | Plunger pump |
-
1997
- 1997-10-30 DE DE19747850A patent/DE19747850A1/en not_active Withdrawn
-
1998
- 1998-07-08 EP EP98943656A patent/EP0935711A1/en not_active Withdrawn
- 1998-07-08 JP JP11510357A patent/JP2001501282A/en active Pending
- 1998-07-08 WO PCT/DE1998/001890 patent/WO1999006704A1/en not_active Application Discontinuation
- 1998-07-08 US US09/269,673 patent/US20010002978A1/en not_active Abandoned
Cited By (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6652245B2 (en) * | 2000-03-28 | 2003-11-25 | Robert Bosch Gmbh | Piston pump for hydraulic vehicle brake system |
EP1275848A1 (en) * | 2001-07-13 | 2003-01-15 | Robert Bosch Gmbh | Fuel pump for a fuel system of an internal combustion engine |
WO2007009664A1 (en) * | 2005-07-21 | 2007-01-25 | Ks Gleitlager Gmbh | Cam ring for an injection pump |
US20080110331A1 (en) * | 2005-07-21 | 2008-05-15 | Ks Gleitlager Gmbh | cam ring for an injection pump |
US20080226479A1 (en) * | 2005-09-06 | 2008-09-18 | Wolfgang Schuller | Piston Pump With Improved Piston |
US8382459B2 (en) * | 2005-09-06 | 2013-02-26 | Robert Bosch Gmbh | Piston pump with improved piston |
US8272858B2 (en) * | 2006-06-22 | 2012-09-25 | Robert Bosch Gmbh | Piston pump |
US20090185924A1 (en) * | 2006-06-22 | 2009-07-23 | Andre Bollwerk | Piston pump |
US8414276B2 (en) * | 2006-06-27 | 2013-04-09 | Robert Bosch Gmbh | Piston pump for a vehicle brake system with a sealing element |
US20090220363A1 (en) * | 2006-06-27 | 2009-09-03 | Wolfgang Schuller | Piston pump for a vehicle brake system with a sealing element |
US20080031754A1 (en) * | 2006-08-07 | 2008-02-07 | Tomoo Harada | Piston Pump |
US7704058B2 (en) * | 2006-08-07 | 2010-04-27 | Advics Co., Ltd. | Piston pump |
US8591209B2 (en) * | 2006-10-17 | 2013-11-26 | Robert Bosch Gmbh | Pump for a vehicle brake system having a valve |
US20100310395A1 (en) * | 2006-10-17 | 2010-12-09 | Oliver Schmautz | Pump for a vehicle brake system having a valve |
US20080310971A1 (en) * | 2007-06-18 | 2008-12-18 | Tomoo Harada | Piston pump |
US7690899B2 (en) * | 2007-06-18 | 2010-04-06 | Advics Co., Ltd. | Piston pump |
US20100284841A1 (en) * | 2007-10-04 | 2010-11-11 | Heiko Jahn | Piston pump for delivering a fluid, and associated brake system |
US20100232994A1 (en) * | 2007-10-04 | 2010-09-16 | Beate Schumann | Piston pump for delivering a fluid, and associated brake system |
US20100232998A1 (en) * | 2007-10-04 | 2010-09-16 | Josef Hipp | Piston pump for delivering a fluid, and associated brake system |
US8845038B2 (en) * | 2007-10-04 | 2014-09-30 | Robert Bosch Gmbh | Piston pump for delivering a fluid, and associated brake system |
US9303640B2 (en) * | 2007-10-04 | 2016-04-05 | Robert Bosch Gmbh | Piston pump for delivering a fluid, and associated brake system |
US9360008B2 (en) * | 2007-10-04 | 2016-06-07 | Robert Bosch Gmbh | Piston pump for delivering a fluid, and associated brake system |
US20100247358A1 (en) * | 2007-11-06 | 2010-09-30 | Harald Hermann | Plastic element, piston pump, and assembly method |
US8523541B2 (en) * | 2007-11-06 | 2013-09-03 | Robert Bosch Gmbh | Plastic element, piston pump, and assembly method |
FR2963953A1 (en) * | 2010-08-19 | 2012-02-24 | Bosch Gmbh Robert | PISTON PUMP AND METHOD OF MAKING SUCH A PUMP |
Also Published As
Publication number | Publication date |
---|---|
EP0935711A1 (en) | 1999-08-18 |
JP2001501282A (en) | 2001-01-30 |
WO1999006704A1 (en) | 1999-02-11 |
DE19747850A1 (en) | 1999-02-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20010002978A1 (en) | Idle volume reducing means in a piston pump for a brake system of a vehicle | |
US6276909B1 (en) | Piston pump for a hydraulic brake system of a vehicle | |
US6457956B1 (en) | Piston pump | |
US6244295B1 (en) | Non-return valve, especially for a piston pump | |
US6224352B1 (en) | Piston pump in a brake system of a vehicle | |
US6079961A (en) | Piston pump for a vehicle brake system having a plastic piston with a wear resistant cam-striking face | |
US6126418A (en) | Piston pump | |
US6652245B2 (en) | Piston pump for hydraulic vehicle brake system | |
US6283733B1 (en) | Piston pump for a vehicle brake system | |
US6082244A (en) | Piston pump | |
US6217300B1 (en) | Piston pump | |
US6109896A (en) | Piston pump | |
US6113365A (en) | Piston pump | |
US20010048884A1 (en) | Piston pump for a brake system for a vehicle | |
JP4067576B2 (en) | Piston pump | |
JP2002514712A (en) | Piston pump | |
US20080025855A1 (en) | Piston Pump And Piston Ring | |
US6146115A (en) | Piston pump | |
US6361295B2 (en) | Means for connecting a closure part to a bush of a piston pump for a brake system | |
US20020100507A1 (en) | Check valve for a piston pump | |
US6786232B2 (en) | Check valve for a piston pump | |
US20090068039A1 (en) | Piston pump | |
US6514056B1 (en) | Piston pump | |
US8801408B2 (en) | Piston pump for a vehicle brake system | |
US6327964B1 (en) | Reciprocating pump |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: ROBET BOSCH GMBH, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SIEGEL, HEINZ;MERKLEIN, DIETER;EHRLICH, JOACHIM;AND OTHERS;REEL/FRAME:010088/0043 Effective date: 19990326 |
|
AS | Assignment |
Owner name: ROBERT BOSCH GMBH, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SIEGEL, HEINZ;MERKLEIN, DIETER;EHRLICH, JOACHIM;AND OTHERS;REEL/FRAME:010784/0888 Effective date: 19990326 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |