Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
  • F15B1/02—Installations or systems with accumulators
  • F15B1/04—Accumulators
  • F15B1/08—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor
  • F15B1/22—Liquid port constructions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
  • F15B1/02—Installations or systems with accumulators
  • F15B1/04—Accumulators
  • F15B1/08—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor
  • F15B1/10—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor with flexible separating means
  • F15B1/103—Accumulators using a gas cushion; Gas charging devices; Indicators or floats therefor with flexible separating means the separating means being bellows
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/20—Accumulator cushioning means
  • F15B2201/205—Accumulator cushioning means using gas
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/30—Accumulator separating means
  • F15B2201/31—Accumulator separating means having rigid separating means, e.g. pistons
  • F15B2201/312—Sealings therefor, e.g. piston rings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/30—Accumulator separating means
  • F15B2201/315—Accumulator separating means having flexible separating means
  • F15B2201/3153—Accumulator separating means having flexible separating means the flexible separating means being bellows
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/30—Accumulator separating means
  • F15B2201/315—Accumulator separating means having flexible separating means
  • F15B2201/3158—Guides for the flexible separating means, e.g. for a collapsed bladder
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/30—Accumulator separating means
  • F15B2201/32—Accumulator separating means having multiple separating means, e.g. with an auxiliary piston sliding within a main piston, multiple membranes or combinations thereof
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/40—Constructional details of accumulators not otherwise provided for
  • F15B2201/41—Liquid ports
  • F15B2201/411—Liquid ports having valve means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/40—Constructional details of accumulators not otherwise provided for
  • F15B2201/415—Gas ports
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B2201/00—Accumulators
  • F15B2201/40—Constructional details of accumulators not otherwise provided for
  • F15B2201/415—Gas ports
  • F15B2201/4155—Gas ports having valve means

Definitions

• the invention relates to a vehicle brake system with a gas pressure accumulator, which has a housing, the interior of which is divided by a metal bellows into a gas space filled with gas and a fluid space, to which a fluid can be supplied and removed under pressure through a supply line.
• a valve arrangement is provided between the fluid space and the feed line, which closes when the pressure in the feed line falls below a minimum value and opens when the pressure exceeds the minimum value.
• the invention further relates to such a gas pressure accumulator.
• the fluid space of such gas pressure accumulators is partially or completely filled with brake fluid against the pressure in the gas space during operation of the vehicle brake system in order to store it.
• a pressure accumulator for hydraulic systems with a housing is known, the interior of which is divided by two metal bellows into a gas and a liquid space, the latter being connected to the hydraulic system via a valve actuated by a metal bellows.
• a valve body is fastened to one of the metal bellows by a holding body, which moves it onto a valve seat when the maximum permissible quantity of liquid has been removed from the liquid space. The valve body thereby closes the liquid space. With this valve only ensures that the metal bellows are not damaged if the pressure in the hydraulic system drops further.
• DE 39 01 261 AI does provide a so-called accumulator charging valve, but its function and mode of operation are not explained in this document.
• Vehicle brake systems have particularly high requirements with regard to the functionality and safety of the units.
• the object of the invention is therefore to overcome the disadvantages described above and to design the vehicle brake system with a gas pressure accumulator in such a way that the gas pressure accumulator remains functional even if another device of the vehicle brake system fails (for example the accumulator charging valve described in DE 39 01 261 AI).
• the object is achieved according to the invention by a vehicle brake system of the type mentioned at the beginning with a gas pressure accumulator in which the valve arrangement closes when the pressure in the supply line exceeds a maximum value and opens when the pressure falls below the maximum value. Furthermore, the object is achieved by such a gas pressure accumulator.
• the pressure in the fluid space of the gas pressure accumulator is limited to a maximum value, so that the metal bellows remains functional even at a particularly high pressure in the feed line.
• the valve arrangement performs a double function. It closes the fluid space when the pressure in the supply line is below minimum pressure or above maximum pressure, and opens it when the pressure is between minimum and maximum pressure.
• gas pressure accumulator provides that the metal bellows executes a lifting movement by means of which the valve arrangement is actuated when the fluid is supplied and discharged. As a result, the closing of the fluid chamber is directly coupled to the movement of the metal bellows, as a result of which a self-contained safety system is formed.
• the valve arrangement has a piston attached to the metal bellows, which can be moved along an axis between two sealing seats, which are arranged axially spaced inside in a hollow cylinder attached to the housing.
• the valve arrangement has a hollow cylinder attached to the metal bellows and directed along an axis, with two axially spaced sealing seats arranged on the inside, which is arranged so as to be axially displaceable around a piston attached to the housing.
• sealing seats provide that they have axially parallel sealing surfaces.
• the piston can slide on these sealing surfaces when the piston or the hollow cylinder is axially displaced.
• the piston maintains the sealing function. Due to elasticity or thermal expansion, the gas and the fluid can change their volume. Furthermore, the housing or the valve arrangement can deform. The volume of the gas space and the fluid space is changed slightly.
• the metal bellows can move on the sealing surfaces and thereby compensate for the differential pressures that occur, without being damaged.
• a coaxial mandrel is advantageously connected to the hollow cylinder, on which the piston is guided or which is guided in the piston. This enables a guided movement of the piston relative to the sealing seats and at the same time achieves a compact design of the gas pressure accumulator.
• the metal bellows is essentially hollow-cylindrical and the piston and the hollow cylinder are arranged radially on the inside in the metal bellows, so that a particularly compact design is achieved.
• An advantageous embodiment provides that the lifting movement of the metal bellows is limited by two end stops in order to specify defined end positions for the movable components. In the end positions, the valve arrangement is closed at the same time.
• a seal or a sealing seat is advantageously formed on at least one end stop.
• a redundant seal is formed at the end stop, which enables a particularly good seal.
• the redundant seal is particularly advantageously arranged on the end stop, which limits the basic position of the piston. This makes the gas pressure. Accumulator is particularly well sealed if the pressure in the supply line is less than the permissible minimum pressure. The pressure in the supply line, the so-called system pressure of the vehicle brake system, can drop below this minimum pressure, the so-called gas pre-pressure, especially in the event of longer vehicle downtimes.
• the gas pressure accumulator can also be provided with a valve arrangement which is provided with at least one redundant seal at an end stop, but does not have the dual function described above.
• the piston as the closing element, first contacts and seals on a first sealing seat during a closing movement this one. The piston then touches a second one
• the first sealing seat which forms an end stop for the closing element, and seals redundantly on this.
• the first sealing seat can correspond to one of the sealing surfaces described above.
• At least one seal is advantageously arranged on the piston, which can seal against at least one sealing seat.
• Fig. 1 shows a first embodiment of a gas pressure accumulator according to the invention in longitudinal section.
• Fig. 2 shows a second embodiment orm of a gas pressure accumulator according to the invention in longitudinal section.
• a gas pressure accumulator 10 shown in FIGS. 1 and 2 has a cup-shaped housing 12 which is closed with a cover 14.
• the interior of the housing 12 is divided into a gas space 20 and a fluid space 22 by a metal bellows 16 adjoining the cover 14 and a disk 18 fastened thereon in a gas-tight manner.
• the gas space 20 is filled with a gas under pressure.
• the cover 14 is pierced by a supply line 24, through which a fluid is supplied to the fluid space 22 when the pressure in the supply line 24 increases.
• the fluid is stored in the fluid space 22 and discharged from it when the pressure in the supply line 24 drops.
• the housing 12 has a cylindrical outer wall 26 with a longitudinal axis 28.
• a disk-shaped end wall 30 adjoins the outer wall 26, in which a threaded bore 32 is formed coaxially, through which the gas can be fed into the gas space 20 with a so-called gas pre-pressure.
• the threaded bore 32 is closed with a screw plug 34 which rests on a sealing washer 36.
• the cover 14 has a disk-shaped closure section 38 which is centered and supported on the outer wall 26 of the housing 12 by means of a shoulder 40 formed thereon on the circumference.
• the disk-shaped closure section 38 is connected to the outer wall 26 in a gas-tight manner by a weld 42.
• a hollow cylinder 44 and a mandrel 46 are integrally formed on the side of the closure section 38 facing the interior of the housing 12.
• a connection 48 is formed in one piece coaxially, which is connected to the interior of the housing 12 by essentially axially directed bores 50, 52 and 54.
• the metal bellows 16 is folded, essentially cylindrical, and gas-tightly connected at its two axial ends by weld seams 56 and 58 to the closure section 38 and the disk 18, respectively.
• the disc 18 is oriented axially normal and is integrally connected to a coaxial rod 60, in which an axial bore 62 is formed, by means of which the rod 60 is guided on the mandrel 46.
• a piston 64 the diameter of which is larger than that of the rod 60, connects in one piece to the rod 60.
• sealing surfaces 66 and 68 On the inner circumference of the hollow cylinder 44 are two axially spaced, axially parallel sealing surfaces 66 and 68 formed, which are axially directed and each form a sealing seat.
• a recess 70 is formed axially between the sealing surfaces 66 and 68 on the inner circumference of the hollow cylinder 44, so that its diameter in this region is larger than the diameter of the sealing seats on the sealing surfaces 66 and 68.
• the piston 64 has a circumferential groove in which a seal 72 in the form of a sealing ring is inserted or injected.
• the seal 72 is designed in such a way that it interacts with the sealing surface 66 or 68 and thereby forms a valve arrangement 74 which can seal twice in a liquid-tight manner.
• FIG. 1 shows the metal bellows 16 in a position in which almost no fluid is stored in the gas pressure accumulator 10, that is to say the pressure in the fluid space 22 has reached its minimum value, the gas admission pressure.
• the piston 64 is almost in a basic position in which the seal 72 rests on the sealing surface 66 and seals it.
• a so-called antechamber 76 is created between the piston 64, the hollow cylinder 44 and the closure section 38 of the cover 14, which is only connected to the connection 48 through the bore 52, but is otherwise closed.
• the valve arrangement is therefore closed between the supply line 24 and the fluid chamber 22.
• the increasing fluid pressure moves the piston 64 connected to the disk 18 almost without friction in the region of a stroke path X, which corresponds to the operating stroke of the gas pressure accumulator 10.
• a stroke path X which corresponds to the operating stroke of the gas pressure accumulator 10.
• fluid can get into the bore 62 so that there is pressure equalization.
• the piston 64 with its seal 72 reaches the sealing surface 68 and seals there at a so-called maximum pressure in the fluid space 22.
• the piston 64 is almost in its end position and the valve arrangement 74 now closes again between the fluid space 22 and the feed line 24 or the antechamber 76.
• the metal bellows 16 is thus protected against damage from excess pressure, since no fluid can flow from the antechamber 76 into the fluid chamber 22.
• the piston 64 with the seal 72 can slide along an axial stroke or X 2 .
• the seal remains during these stroke paths X and X., while a slight pressure equalization between the fluid space 22 and the antechamber 76 is possible. In this way, elasticity and thermal expansion can be balanced as described above.
• a phase 78 is formed in the axially lower, inner end of the piston 64 in FIG. 1 and an end stop 80 opposite the piston 64 on the closure section 38, on which the Piston 64 can be defined.
• a seal 82 is inserted into the closure section 38, which together with a sealing seat 84 formed opposite on the piston 64 forms a redundant seal of the piston 64 in the basic position.
• the seal 82 can alternatively be used in the piston 64.
• An end stop 86 is formed on the inside of the end wall 30, against which the disk 18 bears in the upper end position of the piston 64 in relation to FIG. 1.
• FIG. 2 shows an exemplary embodiment of a gas pressure accumulator 10, which is constructed similarly to that shown in FIG. 1.
• the disk 18 is integrally connected to the rod 60 and a hollow cylinder 44 '.
• the rod 60 is guided axially displaceably in a bore 54 'of the dome 46 and penetrated by a bore 62' which connects the bore 50 to the antechamber 76.
• a piston 64' is formed in one piece with the mandrel 46 '.
• the hollow cylinder 44 ' is moved when the disk 18 is lifted, while the piston 64' remains stationary. Otherwise, the function of the valve arrangement is the same as that described above for FIG. 1.
• an end stop 80 ' is formed on the piston 64'. Furthermore, an axially directed seal 82 'is arranged on the piston 64' and, with an opposite sealing seat 84 'on the disk 18, forms a redundant seal of the piston 64' in the basic position.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Supply Devices, Intensifiers, Converters, And Telemotors (AREA)
• Valves And Accessory Devices For Braking Systems (AREA)
• Braking Systems And Boosters (AREA)
• Filling Or Discharging Of Gas Storage Vessels (AREA)

Priority Applications (1)

Applications Claiming Priority (3)

Related Child Applications (1)

Publications (2)

Family

ID=7928725

Family Applications (2)

Family Applications After (1)

Country Status (8)

Families Citing this family (23)

Family Cites Families (18)

• 1999
  • 1999-11-11 DE DE19954326A patent/DE19954326B4/de not_active Expired - Fee Related
• 2000
  • 2000-11-02 EP EP00981234A patent/EP1228318B1/fr not_active Expired - Lifetime
  • 2000-11-02 DE DE50003583T patent/DE50003583D1/de not_active Expired - Lifetime
  • 2000-11-02 JP JP2001536883A patent/JP2003514202A/ja active Pending
  • 2000-11-02 ES ES00981234T patent/ES2206332T3/es not_active Expired - Lifetime
  • 2000-11-02 AT AT02016285T patent/ATE307979T1/de not_active IP Right Cessation
  • 2000-11-02 AT AT00981234T patent/ATE248994T1/de not_active IP Right Cessation
  • 2000-11-02 EP EP02016285A patent/EP1251282B1/fr not_active Expired - Lifetime
  • 2000-11-02 AU AU18553/01A patent/AU1855301A/en not_active Abandoned
  • 2000-11-02 DE DE50011469T patent/DE50011469D1/de not_active Expired - Lifetime
  • 2000-11-02 WO PCT/EP2000/010809 patent/WO2001034984A2/fr active IP Right Grant
  • 2000-11-02 ES ES02016285T patent/ES2250552T3/es not_active Expired - Lifetime
• 2002
  • 2002-05-09 US US10/143,731 patent/US6616247B2/en not_active Expired - Fee Related
  • 2002-08-09 US US10/216,064 patent/US6666529B2/en not_active Expired - Fee Related
  • 2002-10-24 JP JP2002309443A patent/JP2003175819A/ja active Pending

Non-Patent Citations (1)

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