Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G15/00—Resilient suspensions characterised by arrangement, location or type of combined spring and vibration damper, e.g. telescopic type
  • B60G15/02—Resilient suspensions characterised by arrangement, location or type of combined spring and vibration damper, e.g. telescopic type having mechanical spring
  • B60G15/06—Resilient suspensions characterised by arrangement, location or type of combined spring and vibration damper, e.g. telescopic type having mechanical spring and fluid damper
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
  • B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
  • B60G17/016—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input
  • B60G17/0162—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input mainly during a motion involving steering operation, e.g. cornering, overtaking
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
  • B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
  • B60G17/018—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the use of a specific signal treatment or control method
  • B60G17/0185—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the use of a specific signal treatment or control method for failure detection
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
  • B60G17/06—Characteristics of dampers, e.g. mechanical dampers
  • B60G17/08—Characteristics of fluid dampers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
  • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
  • F16F9/32—Details
  • F16F9/48—Arrangements for providing different damping effects at different parts of the stroke
  • F16F9/49—Stops limiting fluid passage, e.g. hydraulic stops or elastomeric elements inside the cylinder which contribute to changes in fluid damping
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
  • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
  • F16F9/32—Details
  • F16F9/58—Stroke limiting stops, e.g. arranged on the piston rod outside the cylinder
  • F16F9/585—Stroke limiting stops, e.g. arranged on the piston rod outside the cylinder within the cylinder, in contact with working fluid
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2202/00—Indexing codes relating to the type of spring, damper or actuator
  • B60G2202/30—Spring/Damper and/or actuator Units
  • B60G2202/31—Spring/Damper and/or actuator Units with the spring arranged around the damper, e.g. MacPherson strut
  • B60G2202/312—The spring being a wound spring
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
  • B60G2204/40—Auxiliary suspension parts; Adjustment of suspensions
  • B60G2204/45—Stops limiting travel
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
  • B60G2204/40—Auxiliary suspension parts; Adjustment of suspensions
  • B60G2204/45—Stops limiting travel
  • B60G2204/4502—Stops limiting travel using resilient buffer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
  • B60G2400/20—Speed
  • B60G2400/204—Vehicle speed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
  • B60G2400/40—Steering conditions
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2800/00—Indexing codes relating to the type of movement or to the condition of the vehicle and to the end result to be achieved by the control action
  • B60G2800/80—Detection or control after a system or component failure

Definitions

• the invention relates to a hydraulic suspension system of a vehicle, especially automobile.
• a hydraulic suspension system of a vehicle in particular a vehicle, comprises for each of the wheels of the vehicle a piston damper movable in its corresponding cylinder and interposed between the body and the wheel stub axle. of the vehicle.
• the role of this damper is to greatly limit the oscillations transmitted by the wheels to the vehicle body when the wheels encounter roughness or obstacles present on the road on which the vehicle is traveling, and to curb the cash movements in the dynamic actions like braking and turning.
• attack stroke In order to limit and brake the piston stroke of the damper in a compression stroke also called attack stroke, the latter comprises a compressible mechanical mechanical stop, or possibly hydraulic.
• the role of this attack stop is also to protect the chassis of the vehicle during the appearance of strong deflections of the corresponding wheel, due to incidents or significant obstacles, such as retarders type back-d donkey.
• the present invention aims to overcome the above disadvantages of the prior art. [007] To achieve this object, the invention relates to a hydraulic suspension system of a vehicle running gear, particularly automobile, according to claim 1.
• the invention also relates to a vehicle, including automobile, comprising such a hydraulic suspension system.
• FIGS. 2A and 2B respectively represent a longitudinal sectional diagram of a controlled damper of a suspension system according to a first embodiment of the invention when the vehicle is at a reference attitude, as well as a graph illustrating the forces delivered by the suspension system corresponding to the position of the piston indicated in FIG. 2A;
• FIG. 3 represents a graph illustrating different stress curves for a controlled damper of the suspension system according to the invention.
• FIGS. 4A and 4B respectively represent a longitudinal sectional diagram of a controlled damper of a suspension system according to a second embodiment of the invention when the vehicle is at a reference attitude, as well as a graph illustrating the forces delivered by the suspension system corresponding to the position of the piston identified in FIG. 4A.
• the suspension of the vehicle comprises, for each wheel of the vehicle, a hydraulic damper 1 comprising a body 2 in the form of a cylinder and a piston 3 movable in the cylinder 2.
• This damper 1 is interposed between the body 6 of the vehicle and the corresponding wheel knuckle.
• each hydraulic damper 1 of the vehicle hydraulic suspension system can be described according to a damping law in which the force exerted by the damper 1 depends on the speed of movement of the corresponding wheel.
• the faster the piston 3 moves in the cylinder 2 of the damper the higher the braking of this piston, and the greater the force exerted by the damper 1 on the body 6 of the vehicle is important.
• the hydraulic suspension system also comprises, for each wheel of the vehicle, a suspension spring 17 mounted around the damper 1 and whose ends are respectively supported against the body 6 of the vehicle via a cup 18 and against a cup 19 secured to the cylinder 2 of the damper.
• the suspension spring 17 is an element of constant stiffness, the behavior of which can be described by a law according to which the force exerted by the spring 17 on the body 6 of the vehicle depends on its compression and therefore on the amplitude of the deflection of the vehicle. the corresponding wheel. In other words, the more the suspension spring 17 is compressed, the greater the force exerted on the body 6 of the vehicle is important.
• the suspension spring 17 essentially serves to carry the body 6 of the vehicle while allowing the deflections.
• the suspension system also comprises, for each wheel of the vehicle, two respectively mechanical and hydraulic driving abutments 7 and 9 respectively mechanical and hydraulic 16 and hydraulic expansion stops respectively.
• Each mechanical stop 7, 16 is similar to a stiffness, and therefore exerts a force on the body 6 according to the movement of the corresponding wheel.
• the force exerted on the body 6 of the vehicle by the mechanical stops respectively of attack 7 and relaxation 16 is even greater than the deflection in attack and relaxation of the corresponding wheel is important.
• Each hydraulic attacking stop 9 and relaxation 15 is in turn assimilable to a damper and therefore exerts a force on the body 6 of the vehicle in depending on the speed of travel of the corresponding wheel.
• the force exerted on the body 6 of the vehicle by the hydraulic stops respectively of attack 9 and relaxation 15 is even greater than the speed of travel of the corresponding wheel is important.
• the hydraulic attacking stops 9 and the trigger 15 are progressive force stops which increase as a function of the stroke, by the progressive reduction of the fluid passages according to their stroke, which also gives an effort of as much bigger than the race is big.
• the mechanical attack abutment 7 is secured to one end of the cylinder 2 of the damper, and positioned axially between the end of the cylinder 2 of the damper and the body 6 of the vehicle. It also has an annular cross-section so as to be traversed by the rod 14 of the piston 3 of the damper 1.
• the mechanical attack stop 7 is compressed between the end of the cylinder 2 of the damper 1 and the body 6 of the vehicle so as to strongly slow the stroke of the piston 3 in the cylinder 2 of the damper.
• the mechanical attack abutment 7 is made of elastomer material having a very high stiffness constant, so that the force exerted by the mechanical attack abutment 7 on the body 6 of the vehicle increases very rapidly with the deflection in attack of the wheel.
• the hydraulic attack stop 9 is mounted in the compression chamber 4 of the cylinder 2 of the damper 1.
• the hydraulic attack abutment 9 comprises a piston 1 1 secured to the bottom bottom wall 12 of the cylinder 2 of the damper, and a cylinder 10 intended to be displaced along the piston 1 1 of the attack abutment 9 by the piston 3 of the damper 1 when it reaches the vicinity of the end of stroke attack.
• the cylinder 10 of the hydraulic abutment 7 forms a compression chamber 20 filled with hydraulic fluid, which is likely to escape from this chamber 20 by leaks around the piston 1 1 of the hydraulic abutment 9 when the piston 3 the damper moves the cylinder 10 of the hydraulic attack stop 9 towards the lower bottom wall 12 of the damper.
• the hydraulic abutment 9 comprises a return spring 21 surrounding the piston 1 1 of the hydraulic abutment 9 and whose ends are supported axially respectively against the lower bottom wall 12 of the cylinder 2 of the absorber, and the annular end edge bordering the orifice of the cylinder 10 of the hydraulic stop 9.
• the return spring 21 allows the cylinder 10 of the hydraulic attack stop 9 to return to the position of rest, the piston 1 1 emerging from this cylinder, when the piston 3 of the damper 1 away from the cylinder 10 of the hydraulic stop 9.
• the hydraulic expansion stop 15 is in turn a floating piston surrounding the rod 14 of the damper 1 so as to maintain an annular space 23 between the rod 14 and the inner edge of the floating piston through which the hydraulic fluid is likely to circulate.
• the hydraulic expansion stop 15 is positioned in the expansion chamber 5 of the cylinder 2 of the damper, axially between the upper end wall 8 of the cylinder 2 of the damper through which the rod 14 of the damper and a collar 22 forming a valve secured to the rod 14 of the damper.
• the mechanical expansion stop 16 is in turn a high stiffness spring positioned in the expansion chamber 5 and whose ends are axially respectively bearing against the floating piston 15 and the upper end wall 8 of the cylinder 2 of the shock absorber 1.
• the vertical scale represents the stroke in millimeters of the piston 3 of the damper in the cylinder 2 of the damper 1 during deflections of the vehicle wheel.
• the horizontal scale is a visual scale representing the force exerted by each element of the hydraulic suspension at a wheel as a function of the stroke of the piston 3 in the cylinder 2 of the corresponding damper 1.
• the zero stroke corresponds to the position of the piston 3 of the damper 1 in the cylinder when the suspension of the vehicle does not undergo any other effort than that exerted by the mass of the vehicle.
• the vehicle is then at the reference base AR.
• the negative races of the piston 3 of the damper in the cylinder 2 correspond to deflections in attack of the wheel, that is to say that the suspension tends to compress and the body 6 of the vehicle to move closer to the road compared to the reference base AR.
• the positive strokes of the piston 3 of the shock absorber 1 in the cylinder 2 correspond to displacements in relaxation of the wheel, that is to say that the suspension tends to relax and the body 6 of the vehicle to move away from the road relative to the reference base AR.
• strokes in attack or relaxation of the piston 3 of the damper 1 between -15 mm and 15 mm from the reference base AR correspond to low energy DLE deflections which represent the solicitations the most frequent, encountered on roads of good quality.
• races in piston stroke 3 of the damper 1 between -15 mm and -50 mm from the reference base AR, and strokes piston 3 of the damper 1 between 15 mm and 50 mm from the reference base AR correspond to medium energy DME deflections which represent also frequent solicitations.
• races in piston attack 3 of the damper 1 beyond -50 mm from the reference base AR, up to the maximum of -80 mm, and races in piston expansion 3 of the damper 1 greater than 50 mm from the reference base AR, up to a maximum of 1 10 mm, correspond to high energy DHE deflections which represent infrequent solicitations. These stresses are encountered especially when the wheels cross a major hurdle-type retarder in the back of a donkey, or a relatively deep pothole.
• the mechanical attack stop 7 is compressed as soon as the stroke of the piston 3 of the damper 1 exceeds an attack stroke of about 10 mm.
• the mechanical attack stop 7 intervenes quickly to slow the stroke of the piston 3 of the damper 1 from the beginning of the medium energy deflections DME.
• the piston 3 of the hydraulic damper 1 causes the displacement of the cylinder 10 of the hydraulic attack stop 9 along its corresponding piston 1 1, to quickly brake the piston 3 of the damper 1 in its cylinder 2 corresponding by adding a braking force depending on the speed to the braking force of the mechanical stop 7.
• each wheel of the vehicle a shock absorber 1b, a suspension spring 17 and two respective mechanical 16 and hydraulic expansion stops 15 as described above.
• the hydraulic suspension system according to the invention also comprises for each wheel of the vehicle a mechanical attack abutment 7b shorter than the mechanical attack abutment 7 of the prior art, as well as an attack abutment hydraulic 9b whose cylinder 10b has an amplitude of displacement along the corresponding piston 1 1b between its end stroke stroke and its limit end of travel between 40 and 60 mm.
• This range of motion is greater than the displacement amplitude of the cylinder 10 of the hydraulic attack stop 9 of the prior art, which is of the order of 30 mm.
• the structure of the cylinder 10b of the hydraulic attack stop 9b is different, since the cylinder 10b comprises in its wall a plurality of through radial holes 13, and allowing the entry or exit of the hydraulic fluid of the compression chamber 4 of the cylinder 2 of the damper 1b when the piston 1 1b and the cylinder 10b of the hydraulic abutment 9b move relative to each other.
• the piston 3 of the hydraulic damper 1b exceeds an attacking stroke CA1 of between 0 and 20 mm, preferably 10 mm, the latter causes the displacement of the cylinder 10b of the hydraulic attack stop 9b along its corresponding piston 1 1 b.
• the overall section of a large number of the holes 13 passing through the cylinder 10b of the hydraulic thrust bearing 9b is sufficiently high to ensure gentle braking of the piston 3 of the shock absorber 1.
• the overall section of a smaller number of holes 13 through the cylinder 10b of the abutment hydraulic attack 9b decreases because an increasing number of through holes 13 are plugged by the piston 1 1 b of the hydraulic attack stop 9b as the cylinder 10b moves along the piston 1 1 b of the hydraulic attack stop 9b in the direction of the lower bottom wall 12 of the cylinder 2 of the damper 1b: this ensures a stronger braking of the piston 3 of the damper 1b in order to protect the body 6 and the frame of the vehicle.
• the attack abutment 7b is compressed and participates in strengthening the braking of the piston 3 of the damper 1.
• the discontinuity of the force exerted by the suspension system during its compression which generates discomfort for the passengers of the vehicle, is greatly reduced thanks to the hydraulic attack stop 9b, whose cylinder 10b has an elongated displacement amplitude, which acts before the mechanical attack stop 7b.
• the force exerted by the hydraulic attack stop 9b depending both on the speed and the displacement amplitude of the piston 3 of the shock absorber 1b in its cylinder 2, the braking of the piston 3 of the The shock absorber is progressively adapted to the amplitude and the speed of its travel in the cylinder 2, in particular for the medium energy DME deflections, which also has a positive effect on passenger comfort.
• the hydraulic attack stop 9b dissipates the energy without accumulating it, thus avoiding any stimulus effect during low and medium energy deflections.
• the damper 1b further comprises piloting means 30 which modify the level of effort generated by the displacement of the piston 3 in the cylinder 2, according to programmed damping laws, acting by an electrical connection connected to a calculator 32.
• the variable level of effort of the displacement of the piston 3 in the cylinder 2 is indicated in FIG. 2B by a variable width of the rectangular zone representing the force of the damper 1b.
• the computer 32 sends a signal to the control means 30, in particular a current of variable intensity, to change the fluid passages on each side of the piston 3 of the damper 1b in order to vary in real time the level of effort and thus the damping of the oscillations of the suspension.
• the computer 32 may comprise a limited number of damping laws, in particular only two predefined laws controlled by a current or an absence of current, which represents a very simple system, or a continuous range of variation of the level of current. 'amortization.
• the hydraulic suspension system according to the second embodiment of the invention also comprises for each wheel of the vehicle a mechanical expansion stop 16b longer than the mechanical expansion stop 16 of the prior art. Therefore, the floating piston of the hydraulic expansion stop 15b according to the second embodiment of the invention has a displacement amplitude around the rod 14 of the damper 1, between its rest position and its end position. relaxation stroke, for example between 40 and 80 mm. This displacement amplitude is greater than the displacement amplitude of the floating piston of the hydraulic expansion stopper 15 of the prior art, which is of the order of 20 to 30 mm.
• the extension of the displacement amplitude of the hydraulic expansion stop 15b makes it possible to reduce the stiffness of the spring of the mechanical expansion stop 16b, so that it contributes little to the braking of the piston 3 of the shock absorber 1 in relaxation.
• the floating piston 15b of the hydraulic expansion stop is formed by an annular ring radially split over its entire thickness and designed to slide along the rod 14 of the damper 1 so as to maintain an annular space. 23b between the rod 14 and the inner edge of the floating piston 15b, while the upper part of the expansion chamber 5 of the cylinder 2 of the damper 1 comprises a wall 2b of substantially frustoconical shape whose cross section decreases in the upper direction towards the wall 8 of the damper 1.
• the force exerted by the detent stops 15b, 16b on the vehicle body increases very gradually with the stroke of the floating piston 15b: as the floating piston 15b moves towards the upper end wall 8 of the cylinder 2 of the damper 1 along the frustoconical wall 2b, the slot and the annular space 23b of the floating piston 15b closes gradually, thereby decreasing the passage section of the hydraulic fluid.
• This therefore ensures a variable damping according to the stroke of the floating piston 15b, significantly improving control of the vertical movements of the vehicle body, and thus the comfort of the vehicle.
• the horizontal axis represents the displacement velocity V of the piston 3 in the cylinder 2, expressed in meters per second
• the axis vertical represents the force expressed in daN on this piston.
• Different damping laws 34 are applied for variable currents applied in the control means 30, presented for an increment of the current of 0.1 A, which range from a very low damping 36 between -75 and +150 daN for a current of 0.4 A, with a high damping 38 between -600 and + 650daN for a current of 1, 6A .
• control means 30 In the case of a lack of current in the control means 30, for example following a failure of the computer 32, these control means are provided to automatically enter a state giving an average damping law 40 which allows to continue the journey with a compromise between comfort and safety which is sufficient.
• the hydraulic suspension system according to the invention comprises existing techniques arranged in a new combination, it can be easily developed and manufactured with reduced costs, using existing production technologies.
• the configuration as described is not limited to the embodiments described above and shown in Figures 2A, 2B, 4A and 4B. It was not given as a non-limiting example. Multiple modifications can be made without departing from the scope of the invention.
• the invention is not limited to a single hydraulic thrust bearing configuration 9b.
• a hydraulic attack stopper 9b whose cylinder 10b is secured to the inner walls of the compression chamber 4 of the damper 1b and whose piston 1 1b is intended to be moved in its corresponding cylinder 10b by the piston 3 of the shock absorber 1.
• any type of hydraulic attack stopper 9b known and adapted to be housed in the compression chamber 4 of a damper 1b may be considered.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Fluid-Damping Devices (AREA)
• Vehicle Body Suspensions (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=58413131

Family Applications (1)

Country Status (3)

Family Cites Families (15)

• 2017
  • 2017-03-03 CN CN201780019607.6A patent/CN109070677B/zh active Active
  • 2017-03-03 WO PCT/FR2017/050476 patent/WO2017162948A1/fr active Application Filing
  • 2017-03-03 EP EP17713725.4A patent/EP3433114A1/de not_active Withdrawn

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