CN111810528A - Closure panel balancing mechanism with friction bearing mechanism - Google Patents

Abstract

The present invention provides a friction bearing mechanism for coupling with a balancing mechanism of a closure panel of a vehicle, the friction bearing mechanism comprising: a bearing seat defining a longitudinal axis; an outer race positioned within the bearing housing and positioned about the longitudinal axis; an inner race positioned within the bearing seat and between the outer race and the longitudinal axis; one or more bearings mounted in the bearing frame and positioned between the inner and outer races such that the inner race is rotatable relative to the outer race about the longitudinal axis; and one or more friction elements positioned between the inner and outer races and adjacent to the one or more bearings, the one or more friction elements biased into engagement with the friction surface of the inner race; wherein relative rotation of the inner race with respect to the outer race results in a frictional force between the one or more friction elements and the friction surface.

Description

Closure panel balancing mechanism with friction bearing mechanism

Technical Field

The present disclosure relates to a friction-based counterbalance system for a closure panel.

Background

Some vehicles are equipped with a closure panel, such as a lift gate, that is driven between an open position (position 2) and a closed position (position 1) using an electric drive system. Retention systems have been proposed to provide such vehicles with the ability to assist the operator of the closure panel in order to retain the third position retention point (or position 2) during opening and closing operations, thereby helping to resist the weight of the closure panel itself. Without these retention systems, the closure panel may droop back at the top of the open range of operation because the closure torque provided by the closure panel weight is greater than the opening torque provided by the electric drive system. In some cases, such a proposed retention system is complex and expensive and may not provide an adequate fail-safe mode (in case of electric motor failure or power outage) while maintaining sufficient manual work by the operator. It is also recognized that there is a need to provide a balancing system as follows: the counterbalance system can provide effective counterbalance force customization for different closure panel weights and configurations (e.g., different center of gravity), including the ability to accommodate a third position hold or stop point and to maintain the functionality of the closure panel.

Other disadvantages of current retention systems include: a large form factor that occupies valuable vehicle cargo space, the need to have additional lift support systems in series, such as gas struts and other counterbalance mechanisms, unacceptable impact on manual opening and closing operations that require greater operator-applied manual force at the panel handle, undesirable force spikes that fail to provide a smoother manual force/torque curve, the need to use vehicle battery power to maintain a third position hold point, and/or temperature effects due to variable manual work required by the operator due to fluctuations in ambient temperature.

Disclosure of Invention

It is an object of the present invention to provide a balancing mechanism which obviates or mitigates at least one of the above-mentioned disadvantages.

A first aspect provides a friction bearing mechanism for coupling with a counterbalance mechanism of a closure panel of a vehicle, the friction bearing mechanism comprising: a bearing seat defining a longitudinal axis; an outer race positioned within the bearing seat and positioned about the longitudinal axis; an inner race positioned within the bearing seat and positioned between the outer race and the longitudinal axis; one or more bearings mounted in the bearing frame and positioned between the inner and outer races such that the inner race is rotatable relative to the outer race about the longitudinal axis; and one or more friction elements positioned between the inner and outer races and adjacent to the one or more bearings, the one or more friction elements biased into engagement with a friction surface of the inner race, wherein relative rotation of the inner race with respect to the outer race results in a frictional force being generated between the one or more friction elements and the friction surface.

A second aspect provides a method for operating a friction bearing mechanism of a balancing mechanism, the method comprising the steps of: mounting a bearing mount on a lead screw of a counterbalance mechanism, the lead screw defining a longitudinal axis, the bearing mount having an outer race positioned within and about the longitudinal axis and an inner race positioned within and between the outer race and the longitudinal axis; providing relative movement between the inner and outer rings about the longitudinal axis via one or more bearings mounted in the bearing frame and positioned between the inner and outer rings; and generating a frictional force between one or more friction elements and a friction surface of the inner ring during the relative movement, the one or more friction elements positioned between the inner and outer rings and adjacent to the one or more bearings, the one or more friction elements biased into engagement with the friction surface of the inner ring.

Other embodiments of the above aspects and other aspects including methods of operation will be apparent based on the following description and the accompanying drawings.

Drawings

By way of example only, reference is made to the accompanying drawings in which:

FIG. 1 is a perspective view of a vehicle having a closure panel assembly;

FIG. 2 is a cross-sectional view of the counterbalance mechanism of FIG. 1 as an offset strut;

FIG. 3 is a cross-sectional view of the friction bearing mechanism of FIG. 2;

FIG. 4 is an enlarged view of the friction bearing mechanism of FIG. 1;

FIGS. 4A and 4B are illustrative embodiments of the friction bearing mechanism of FIG. 1;

FIG. 5 is a cross-sectional view of the friction bearing mechanism of FIG. 2 with an alternative electric motor;

FIG. 5A is a cross-sectional view of the friction bearing mechanism of FIG. 2 with an alternative electric motor, according to another illustrative embodiment; and

FIG. 6 is an example operation of the friction bearing mechanism of FIG. 2.

Detailed Description

In the present specification and claims, the use of the article "a," "an," or "the" in reference to an item is not intended to exclude the possibility of including multiple items in some embodiments. It will be apparent to those of ordinary skill in the art that in at least some examples in this specification and the appended claims, multiple items may be included in at least some embodiments. Likewise, use of plural forms on an item is not intended to exclude the possibility of including one of the items in some embodiments. It will be apparent to those skilled in the art that in at least some examples in this specification and the appended claims, one of the items may be included in at least some embodiments.

A counterbalance mechanism is provided that may be advantageously used with a vehicle closure panel to provide an open and close fail-safe mode in the event of a power actuator failure or disconnection, particularly for land-based, sea-based, and/or air-based vehicles. Other applications of the balancing mechanism, typically for closure panels located both in and outside of vehicle applications, include advantageously assisting in the optimization of the overall retention and manual work force for closure panel operation. It is also recognized that the examples of counterbalancing mechanisms provided below may be advantageously used as the sole means of opening and closing assistance for the closure panel, or may be advantageously used in conjunction (e.g., in series) with other closure panel biasing members (e.g., spring-loaded hinges, biasing struts, etc.). In particular, the counterbalance mechanism may be friction-based and used to provide a holding force (or torque) for the closure panel, as described further below. Further, it is recognized that the counterbalance mechanism may be integral with the biasing member 37, such as a spring-loaded strut, and/or the counterbalance mechanism may be provided as a component of the closure panel assembly, as further described below. It is recognized that the biasing member 37 incorporating the friction based counterbalance mechanism may be implemented as a strut. The struts may be of the biasing type (e.g., springs and/or inflators providing the bias). The struts may be of an electromechanical type (e.g., driven by an optional integral motor assembly with a spring and/or inflator providing the bias).

Referring to FIG. 1, a vehicle 10 having a body 11 with one or more closure panels 14 is shown. One example configuration of the closure panel 14 is a closure panel assembly 12 that includes a friction-based counterbalance mechanism 37 (e.g., a friction-based counterbalance mechanism 37 incorporated in a biasing member implemented by way of example as a strut). With respect to the vehicle 10, the closure panel 14 may be referred to as a bulkhead or door that is typically hinged in front of the opening 13, but is sometimes attached in front of the opening 13 by other means, such as rails, the opening 13 being used for ingress of people and/or cargo and egress from the interior of the vehicle 10. It is also recognized that the closure panel 14 may be used as an access panel for systems of the vehicle 10, such as the engine compartment, and also for the conventional trunk of an automotive type vehicle 10. The closure panel 14 may be opened to provide access to the opening 13, or the closure panel 14 may be closed to block or otherwise restrict access to the opening 13. It is also recognized that there may be one or more intermediate retention positions between the fully open and fully closed positions of the closure panel 14, as provided at least in part by the counterbalance mechanism 37, as further described below. For example, the counterbalance mechanism 37, when positioned in one or more intermediate Hold positions, may assist in biasing movement of the closure panel 14 away from the one or more intermediate Hold positions, which are also referred to as a third position Hold point (TPH) or a Stop N Hold point (Stop-N-Hold). It is also appreciated that the counterbalance mechanism 37 can be provided as a component of the closure panel assembly such that the counterbalance mechanism 37 component can be separate from the one or more biasing struts.

The closure panel 14 may be opened manually and/or electrically via a closure panel drive system (not shown), wherein the powered closure panel 14 may be found on a minivan, high-end automobile, or Sport Utility Vehicle (SUV), or the like. In addition, one feature of the closure panel 14 is: because of the weight of the materials used in the manufacture of the closure panel 14, some form of force-assisted opening and closing mechanism (or mechanisms) is used to facilitate the operation of opening and closing operations by an operator of the closure panel 14 (e.g., a vehicle driver). The force assisted opening and closing mechanism may be provided by a counterbalance mechanism 37, any biasing member (e.g., spring loaded hinge, spring loaded strut, gas loaded strut, electromechanical strut, etc.), and a closure panel drive system when used as part of a closure panel assembly, such that the counterbalance mechanism 37 is configured to provide a friction based retention torque (or force) that acts against the weight of the closure panel 14 over at least a portion of the panel open/close path about the third position retention point to help retain the position of the closure panel 14 proximate the third position retention point. It is appreciated that the balancing mechanism 37, which is an electromechanical strut, may have a lead screw 140 (see fig. 2), the lead screw 140 being actively operated by a motor 72 (e.g., an electric motor, see fig. 5), or the lead screw 140 being passively operated such that the lead screw 140 is free to rotate about its longitudinal axis, but is not actively driven by the motor. The lead screw 140 is an example of a rotatable (second) component of the balancing mechanism 37. For example, and referring to fig. 5A included herein and suitable for illustrating the use of the friction bearing mechanism 50, fig. 5A is for illustrating an embodiment of the Electromechanical strut of fig. 4A of commonly owned U.S. patent No. 10100568 (the' 568 patent), entitled "Electromechanical strut with a lateral support feature," which is incorporated herein by reference in its entirety. Fig. 5A corresponds to fig. 4A of the '568 patent but the reference numerals of fig. 5A have portions with a "'". The friction bearing mechanism 50 may also be used with a powered actuator or powered drive unit, such as a powered actuator of the type shown in US9174517 entitled "Powerswing door activator," the entire contents of which are incorporated herein by reference.

In the context of vehicle 10, closure panel 14 may be a lift gate as shown in fig. 1, or closure panel 14 may be some other type of closure panel 14, such as a swing-up door (i.e., sometimes referred to as a gull-wing door) or a conventional type of door that is hinged at a forward or rearward facing edge of the door and thus allows the door to swing (or slide) away from (or toward) opening 13 in body 11 of vehicle 10. Sliding door embodiments of the closure panel 14 and roof door embodiments of the closure panel 14 are also contemplated such that the sliding door may be of the type that opens by sliding horizontally or vertically, whereby the door may be mounted on or suspended from: the track provides a large opening 13 for equipment to be loaded and unloaded through the opening 13 without obstructing access. The roof door is a type of door that sits on top of the vehicle 10 and lifts upward in some manner to provide access to vehicle occupants via an opening 13 (e.g., automobile roof, aircraft roof, etc.). The canopy door may be connected (e.g., hinged and/or connected at a defined pivot axis for travel along a track) to the body 11 of the vehicle at the front, sides, or rear of the door as the application permits.

Referring again to fig. 1, in the context of a closure panel vehicular application by way of example only, the closure panel 14 is movable between a closed position and an open position (as shown). In the illustrated embodiment, the closure panel 14 is pivotable between the open and closed positions about a pivot axis that is preferably configured to be horizontal or parallel to a support surface of the vehicle 10. In other embodiments, the pivot axis may have some other orientation, such as vertical or extending outwardly at an angle from a support surface of the vehicle 10. In other embodiments, the closure panel 14 may move in a manner other than pivoting, for example, the closure panel 14 may translate along a predetermined trajectory between the open and closed positions or may undergo a combination of translation and rotation.

The counterbalance mechanism 37 provides a connection of the closure panel 14 to the vehicle body 11 at the pivotal connections 18, 38 (see fig. 1). The counterbalance mechanism 37 includes a lower housing 112, an upper housing 114, and an extendable member (e.g., shaft/lever) 35. The pivot mounts 18 at the ends of the lower shell 112 may be pivotally mounted to portions of the vehicle body 11 that define an interior cargo area in the vehicle 10. The second pivot mount 38 is attached to a distal end of the extendable member 35 relative to the upper housing 114, and the second pivot mount 38 is pivotally mounted to the lift gate 14 of the vehicle 10. It is recognized that the housings 112, 114 may be collectively referred to as a housing 115.

Referring to fig. 2, an example configuration of the balancing mechanism 37 is shown, the balancing mechanism 37 including an elongated member 40 (e.g., a rod, a tube, etc.) of the extendable member 35, the elongated member 40 defining a longitudinal axis 41. Thus, the elongate member 40 may be coupled to the pivot mount 38 at the distal end 20 and to the travel member 45 at the proximal end 22. The travel member 45 is coupled at one end 24 to the lead screw 140, providing relative movement of the travel member 45 along the longitudinal axis 41. The travel member 45 may be coupled to the threads 141 of the lead screw 140 by the threaded hole 46, and thus, the travel member 45 rotates about the lead screw 140 and along the lead screw 140 as the travel member 45 travels along the longitudinal axis 41. It is also appreciated that as the lead screw 140 rotates about the longitudinal axis 41 and within the threaded bore 46, the travel member 45 does not rotate on the lead screw 140, rather, the travel member 45 travels linearly along the longitudinal axis 41 and linearly along the body of the lead screw 140. Thus, as the lead screw 140 rotates, the extendable member 35 also extends or retracts relative to the housing 115.

The counterbalance mechanism 37 may also optionally include a biasing element 68, the biasing element 68 assisting in the opening and closing of the closure panel 14. At the other end 26 of the lead screw, the friction bearing mechanism 50 may be connected to the lead screw 140 by one of the collars 52, 54 (e.g., the inner collar 54, see the figures) such that the connected collars 52, 54 and the lead screw 140 undergo common rotation. Thus, as described further below, as the lead screw 140 rotates about the longitudinal axis 41, the friction bearing mechanism 50 also operates and thus provides friction during movement of the extendable member 35 into and out of the housing 115. Although the friction bearing member 50 is illustratively shown as rotatably supporting the lead screw 140, the friction bearing member 50 may also be provided to support other rotatable members of the balance mechanism 37, such as the rotary motor shaft 51, a rotating member of a gear train, such as the planetary gear train 32' disposed between the lead screw 140 and the motor 72, and the like.

Referring to fig. 2, 3, 2, 3 show a cross-sectional view of a friction bearing mechanism 50, the friction bearing mechanism 50 including a bearing mount 48, an outer race 52 fixed to the bearing mount 48, an inner race 54 connected to the end 26 of the lead screw 140, and a bearing 56, the bearing 56 being positioned between the outer race 52 and the inner race 54 such that relative displacement (about the longitudinal axis 41) of the inner race 54 relative to the outer race 52 causes the bearing 56 to rotate. The bearing mount 48 is fixed/mounted to the lower housing 112 (see FIG. 2) such that the outer race 52 is inhibited from rotating as the inner race 54 and the lead screw 140 rotate about the longitudinal axis 41. Alternatively, the bearing seat 48 may not be provided, and the outer race 52 is fixed/mounted to the lower housing 112, the lower housing 112 being an example of a non-rotatable (first) component. The first and second parts of the counterbalance mechanism 37 may rotate relative to each other. For example, the first member may rotate while the second member does not rotate. For example, the second member may rotate while the first member does not rotate. For example, both the first and second components may rotate. A bearing bracket 58 (e.g., an annular bracket) houses the bearing 56 between the inner and outer rings 54, 52 such that the bearing bracket 58 is free to rotate about the longitudinal axis 41 as the inner ring 54 is displaced relative to the outer ring 52 as the lead screw 140 rotates.

The friction bearing mechanism 50 also has a bearing cap 60, the bearing cap 60 being used to position the bearing bracket 58 between the inner and outer races 54, 52. The gap 59 between the bearing 56/bearing cage 58 and the bearing cap 60 may be used to retain a quantity of lubricating fluid (e.g., bearing grease) to provide lubrication for the rotation of the bearing within the bearing cage 58. Further, one or more friction elements 62 (e.g., friction elements composed of a friction generating material such as, but not limited to, rubber or plastic, e.g., an elastomeric material) are mounted to the bearing cap 60, for example, to serve as friction member biasing elements 63, and the one or more friction elements 62 are biased into engagement with friction surfaces 64 of the inner race 54. The bearing cap 60 may be provided as a one-piece unit with a resilient biasing element, for example made of metal, which may act as a spring and which has a friction generating portion, such as a plastically formed friction element 62. It is appreciated that these components may be arranged not to be integrally formed, but to be connected together. The bias may be provided, for example, by a friction fit between the outer race 52 and the bearing seat 48, thereby compressing the friction element 62 between the inner race 54 and the outer race 52. For illustration only, a series of friction generating regions 66 are shown in which friction forces 68 will be generated between the friction surface 64 and the friction elements 62 as the inner race 54 rotates relative to the outer race 52 about the longitudinal axis 41 in the friction generating regions 66. For example, the bearing bracket 58 may be positioned such that contact is made between the bearing bracket 58 and the bearing cap 60 and/or the friction element 62.

Fig. 4 shows an enlarged view of the friction element 62 in contact with the friction surface 64 of the inner race 54 when mounted on the bearing cap 60 between the inner race 54 and the outer race 52. It is appreciated that the shape of the friction element 62 may be serpentine shaped to facilitate biasing into engagement with the friction surface 64.

Fig. 4A shows another embodiment illustrating a friction element 62 biased into contact with the inner race 54, or alternatively biased into contact with the outer race 52, under the influence of a friction member biasing element 63 illustratively acting against the other of the inner race 54 or the outer race 52.

Fig. 4B shows another embodiment illustrating a friction element 62, described below, which friction element 62 is in biased contact with bearing 56 under the influence of a friction member biasing element 63, illustratively embodied as a bearing cap 60. The embodiment of fig. 4B illustrates that friction is generated indirectly between the inner and outer rings 54, 52 by resisting rotation of the bearing 56, which is commonly known to be employed to eliminate friction between the inner and outer rings 54, 52, as opposed to directly between the inner and outer rings as shown in fig. 3 and 4A.

It should be appreciated that the purpose of the known bearing 56 is to minimize friction between the inner and outer races 54, 52, and thus the bearing 56 provides a relatively small amount of friction compared to that generated by the friction member 62.

Fig. 5 shows a portion of the balancing mechanism 37, the portion of the balancing mechanism 37 including the friction bearing mechanism 50, a portion of the lead screw 141, the housing 115, and the optional coupling 70 coupled with the optional electric motor 72 (the electric motor 70 for actively driving the lead screw 141 in rotation about the longitudinal axis 41-see fig. 2).

Referring to fig. 6, an example operation 100 of the friction bearing mechanism 50 is shown. At step 102, the bearing mount 48 is mounted on the lead screw 140 of the balancing mechanism 37, the lead screw 140 defining the longitudinal axis 41, the bearing mount 48 having an outer race 52 and an inner race 54, the outer race 52 being positioned within the bearing mount 48 (and positioned about the longitudinal axis 41), the inner race 54 being positioned within the bearing mount 48 and between the outer race 52 and the longitudinal axis 41. At step 104, relative movement between the inner and outer rings 54, 52 about the longitudinal axis 41 is provided through one or more bearings 56 mounted in the bearing bracket 58 (e.g., passive relative movement by manually opening or closing the closure panel 14 by a user of the vehicle 10-see fig. 1, or active relative movement by operating the electric motor 72-see fig. 5). At step 106, a friction force 66 is generated between the one or more friction elements 62 and the friction surface 64 of the inner race 54 during the relative movement, the one or more friction elements 62 being positioned between the inner race 54 and the outer race 52 adjacent to the one or more bearings 56. It is appreciated that the one or more friction elements 62 are biased into engagement with the friction surface 64 of the inner race 54.

It is also possible to provide another method for operating a friction bearing mechanism of a balancing mechanism, the other method comprising the steps of: mounting a bearing housing on a rotatable member 53 of the counterbalance mechanism, the rotatable member defining a longitudinal axis, the bearing housing having an outer race positioned within and about the bearing housing and an inner race positioned within and between the outer race and the longitudinal axis; providing relative movement between the inner and outer rings about the longitudinal axis via one or more bearings positioned between the inner and outer rings; and generating a frictional force between one or more friction elements and a friction surface of at least one of the inner and outer races during the relative movement, the one or more friction elements positioned between the inner and outer races, the one or more friction elements biased into engagement with the friction surface of the inner race.

Claims (14)

1. A friction bearing mechanism (5) for coupling with a counterbalance mechanism (37) of a closure panel (14) of a vehicle (10), the friction bearing mechanism comprising:

a bearing seat (48), the bearing seat (48) defining a longitudinal axis (41);

an outer race (52), the outer race (52) positioned within the bearing seat and positioned about the longitudinal axis;

an inner race (54), the inner race (54) positioned within the bearing seat and between the outer race and the longitudinal axis;

one or more bearings (56), the one or more bearings (56) mounted in a bearing frame (58) and positioned between the inner and outer races such that the inner race is rotatable relative to the outer race about the longitudinal axis; and

one or more friction elements (62) positioned between the inner and outer races and adjacent to the one or more bearings, the one or more friction elements biased into engagement with a friction surface (64) of the inner race,

wherein relative rotation of the inner race with respect to the outer race results in a frictional force (66) being generated between the one or more friction elements and the friction surface.

2. The friction bearing mechanism of claim 1, wherein the bearing housing is mounted within a housing (115) of the balance mechanism.

3. The friction bearing mechanism of claim 2, further comprising a lead screw (140), the lead screw (140) being connected to the inner ring such that rotation of the lead screw causes the relative rotation of the inner ring.

4. The friction bearing mechanism of claim 3 further comprising an extendable member positioned in an upper housing (114) of the housing along the longitudinal axis and mounted to a travel member (45) coupled to one end (24) of the lead screw.

5. The friction bearing mechanism of claim 1, further comprising a bearing cap (60), the bearing cap (60) being positioned between the inner and outer races such that the one or more friction elements are mounted on the bearing cap.

6. The friction bearing mechanism of claim 1, wherein the biasing into engagement is provided by positioning the outer race in the housing by means of a friction fit between the outer race and the bearing seat.

7. The friction bearing mechanism of claim 5, wherein the one or more friction elements comprise an elastomeric material.

8. The friction bearing mechanism of claim 7, wherein the resilient material is rubber.

9. The friction bearing mechanism of claim 1, wherein the one or more friction elements are serpentine shaped to facilitate said biasing into engagement.

10. A method for operating a friction bearing mechanism of a balancing mechanism, the method comprising the steps of:

mounting a bearing mount on a lead screw of the balancing mechanism, the lead screw defining a longitudinal axis, the bearing mount having an outer race positioned within and about the bearing mount and an inner race positioned within and between the outer race and the longitudinal axis;

providing relative movement between the inner and outer rings about the longitudinal axis via one or more bearings mounted in a bearing frame and positioned between the inner and outer rings; and

generating a frictional force between one or more friction elements and a friction surface of the inner ring during the relative movement, the one or more friction elements positioned between the inner and outer rings and adjacent to the one or more bearings, the one or more friction elements biased into engagement with the friction surface of the inner ring.

11. A method for operating a friction bearing mechanism of a balancing mechanism, the method also being configurable to include the steps of:

mounting a bearing housing on a rotatable member of the balance mechanism, the rotatable member defining a longitudinal axis, the bearing housing having an outer race positioned within and about the bearing housing and an inner race positioned within and between the outer race and the longitudinal axis;

providing relative movement between the inner and outer rings about the longitudinal axis via one or more bearings positioned between the inner and outer rings; and

generating a frictional force between one or more friction elements and a friction surface of at least one of the inner and outer races during the relative movement, the one or more friction elements positioned between the inner and outer races, the one or more friction elements biased into engagement with the friction surface of the inner race.

12. A friction bearing mechanism (5) for coupling with a counterbalance mechanism (37) of a closure panel (14) of a vehicle (10), the counterbalance mechanism including first and second components rotatable relative to one another, the friction bearing mechanism comprising:

an outer race (52), the outer race (52) coupled to one of the first and second components and about a longitudinal axis;

an inner ferrule (54), the inner ferrule (54) positioned between the outer ferrule and the longitudinal axis;

one or more bearings (56), the one or more bearings (56) positioned between the inner and outer races such that the inner race is rotatable relative to the outer race about the longitudinal axis; and

one or more friction elements (62), the one or more friction elements (62) biased into engagement with a friction surface (64) of at least one of the inner and outer races,

wherein relative rotation of the inner race with respect to the outer race results in a frictional force (66) being generated between the one or more friction elements and the friction surface.

13. A balance mechanism having a friction bearing mechanism substantially as shown and described herein.

14. A powered actuator having a friction bearing mechanism substantially as shown and described herein.

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