DE102011085885A1 - Torque transmission device for transmission of torque from combustion engine to gearbox of motor vehicle, comprises torque transmission device element, which is designed as insulation element preventing electric current passage - Google Patents

Abstract

The torque transmission device comprises a torque transmission device element (114), which is designed as an insulation element preventing an electric current passage. The torque transmission device element is connected with an element to be insulated in a torque-proof manner. The torque transmission device element partially has an insulating coating of an electrically insulating material. The insulation of the torque transmission device element is formed in a contact area between the torque transmission device element and the element to be insulated.

Description

The present invention relates to a torque transmission device, in particular for a motor vehicle for transmitting torque from a drive unit, in particular from an internal combustion engine to an output unit, in particular a transmission.

Such a torque transmission device may be, for example, a clutch assembly, a dual-mass flywheel or a torque converter. Such torque transmission devices are usually arranged in the drive train of a vehicle between a drive unit, the engine, and an output unit, the transmission. In modern powertrains, however, it has been shown that while starting the vehicle by a starter while much of the current via a ground cable to the body is derived, the remaining residual current but starting from the starter via various components of the drive train to the transmission is transferable , The resulting current input into the gearbox can lead to damage of transmission components and malfunction. For example, welding of moving parts may occur due to the effect of heat from the flow.

From the prior art of DE 3721705 a torsional vibration damper is known whose relative to its housing movable springs are electrically insulated to prevent the movable springs in a welding process for welding the housing parts also weld due to the heat generated with the housing and thus lose their mobility.

However, the torsional oscillator known from the prior art provides only insulation for or during the assembly process. The continuous load on the current input when starting the internal combustion engine is not prevented by the disclosed electrical insulation element. The reason for this is that the insulating element between the housing and a relatively movable element - namely on the spring - is arranged, which can lead to abrasion of the coating, especially in the case of insulating coatings, whereby the insulating effect is not given.

It is therefore an object of the present invention to provide a torque transmission device which provides current isolation over the life of the torque transmission device.

This object is achieved by a torque transmission device according to claim 1.

The invention is based on the idea to provide a torque transmission device for a drive train of a motor vehicle, in which a current insulation is provided, which prevents a current input from a starter to a transmission, wherein the current-insulating element is formed as an insulating element, an electric current passage preventing torque transmission device element which rotatably connected to an element to be isolated.

The arrangement between two non-rotatably connected elements of the torque transmitting device reduces the relative movement between the elements, so that the insulating element undergoes no or only a negligible mechanical load. This is particularly advantageous for an embodiment in which an element of the torque transmission device has an electrically insulating coating. Since no or only a negligible relative movement occurs between the elements, the insulating element and the element to be insulated, the coating is not mechanically stressed and allows isolation over the entire life of the torque transmitting device. In this case, the insulating coating can be applied partially or over the entire area on the torque transmission device element designed as an insulation element.

The negligible relative movement also makes it possible to implement the insulating coating preferably only a few micrometers thick, in particular 1 to 50 microns, preferably 3 to 30 microns, so that it has no significant influence on the dimensioning and operation of the torque transmission device.

According to a further advantageous embodiment, the at least partially insulating coating may be formed as a ceramic or paint layer. Preferably, ceramic layers consist of silicon oxide or layers of chromium or chromium nitride compounds or comprise an amorphous carbon structure.

Instead of a ceramic or lacquer layer, the coating may also be made of rubber or based on a rubber compound. In general, it is advantageous to use a material which on the one hand is suitable as a coating material, and on the other hand has a high electrical resistance, which is a current passage from the formed as an insulating element torque transmitting device element and the insulating element prevented. Also, for example, an anodized aluminum element is conceivable.

Although it is possible to coat the entire torque transmitting device element formed as an insulating element, it may also be advantageous for the insulation of the torque transmitting device element formed as an insulating element to be formed on at least one contact area between the torque transmitting device element formed as an insulating element and the element to be insulated.

This has the advantage that, on the one hand, resources are spared, since only the actual contact area is coated, and, on the other hand, any further component properties, such as, for example, a friction property, are not impaired or changed due to the coating and thus have to be taken into account.

In particular, it is advantageous, as a further embodiment shows, when the insulation is formed on the torque transmitting device element formed as an insulating element in the range of at least one detachable and / or non-detachable connection between the designed as an insulating element torque transmitting device element and the element to be insulated. In this case, the region of a rivet connection and / or a toothing and / or a plug connection and / or a screw connection may be mentioned as preferred isolation regions. The advantage of the insulation in these areas is that, especially at the direct contact points, a current input preferably takes place and can easily be prevented by the inventive attachment of an insulation.

Furthermore, it can be advantageous if the torque transmitting device element formed as an insulating element has a coated rivet and / or a coated rivet hole and / or a coated rivet bearing surface and / or a coated screw and / or a coated screw hole and / or a coated screw bearing surface.

According to a further advantageous embodiment, insulation may be effected by means of a coated toothing and / or a coated tooth seat, wherein in particular the toothing or the tooth seat is preferably first hardened and / or preferably chemically nickel-plated or chromium-plated before an insulating coating is then applied.

According to a further advantageous embodiment, the torque transmitting device element formed as an insulating element is made entirely of an electrically insulating material, in particular of plastic and / or ceramic. It is particularly advantageous if the formed as an insulating element torque transmitting device element is designed as a receptacle of an opening, in particular of a rivet and / or screw hole sleeve. Such sleeves can be easily inserted before riveting or screwing into the openings and thus provide the electrical insulation according to the invention. Of course, it is also possible, the fastener, z. As the rivet or the screw, even from an electrically insulating material or to provide with insulation.

Furthermore, the torque transmitting device element designed as an insulating element may be formed as a disk or at least partially as a disk which at least partially covers a contact region between the torque transmitting device element formed as an insulating element and the element to be insulated.

Advantageously, the insulation described above can be used in particular in a clutch assembly and / or a torsional vibration damper.

According to a further advantageous embodiment, a torsional vibration damper according to the invention has at least one primary mass assigned to the output side and a secondary mass assigned to the drive side, which are non-rotatably connected, preferably via rivet connections, to a hub disc. In this case, preferably designed as an insulating element torque transmitting device element is determined via the hub disc. It is particularly advantageous if the hub disc has the insulating coating at least partially, preferably at its radially outer region and / or in rivet holes and / or at the rivet supports and / or at the rivets and / or in the entire contact region between hub disc and secondary mass.

Since the attachment of the torsional vibration damper to the drive unit, either directly by screwing to the crankshaft or indirectly by intermediate components, such as a flexplate, stud bolts and / or shims, the power is transmitted on the primary side to the primary mass, the current within the torsional vibration damper Transfer components such as cover plate and sealing plates to the secondary mass. With a connection of the Torsionsschwingungsdämpfers with the transmission, for example via Hirth or splines is introduced in particular via the hub disc of the current into the transmission. The coating according to the invention, preferably on the hub disc, prevents such current entry.

According to a further advantageous embodiment, the hub disc may also have rivets made of an electrically insulating material and / or received by the rivet holes sleeve-like insulation elements. Alternatively or in addition to the coating, this represents a particularly good and simple insulation of the hub disk with regard to the secondary mass.

If the torsional vibration damper has a spline, it is also advantageous to provide the spline with a partially insulating coating, the coating preferably being formed at the axial connection points and / or the rivet holes and / or the rivet supports of the spline.

According to a further advantageous embodiment, the torsion damper has a toothing, in particular a Hirth toothing, which is chemically hardened and / or nickel-plated and / or chrome-plated and provided with the electrically insulating coating, wherein in the case of Hirth toothing preferably also the screws and / or the Screw holes of Hirtverzahnung can be coated.

Instead of or in addition to the electrical insulation on the hub disc or the teeth, ie within the torsion damper, a torsional vibration damper according to the invention can also be electrically insulated against a current input to the primary mass. For this purpose, as a further preferred embodiment shows, the torsion damper radially outwardly comprise a sprocket, which is designed to cooperate with a starter, wherein the sprocket and / or the torsional vibration damper are formed as an insulating element. Preferably, an insulating coating is arranged on the contact region between the sprocket and the torsion damper.

Alternatively or additionally, the primary mass can also have the insulating coating and / or the coated rivet holes and / or coated rivets and / or rivets made of an electrically insulating material and / or sleeve-like insulation elements accommodated by the rivet holes at their contact area to a drive plate connected to the drive unit ,

According to a further embodiment, a drive plate rotatably connected to a drive unit drive plate on its output side contact area to a non-rotatably mounted torque transmitting device having an inventive insulating coating.

The electrical insulation according to the invention before or on the primary mass has the advantage that even the torsion damper itself and in particular its movable elements, such as the springs are protected against a current input and a resulting damage.

Further advantages and advantageous embodiments are defined in the subclaims, the description and the figures.

In the following, the invention will be described in more detail with reference to exemplary embodiments illustrated in the figures. The exemplary embodiments shown are of purely exemplary nature and do not specify the scope of the invention. This is defined solely by the appended claims.

Show it:

1 a schematic representation of an electrical current flow through a torsion damper;

2a a schematic representation of a first preferred embodiment of the present invention;

2 B : an enlarged view of the current input area for the in 2a shown torsion damper;

2c : a schematic representation of an inventively designed hub disc for the in 2a shown torsion damper in a schematic sectional view and

2d : in supervision;

3a a schematic representation of a second preferred embodiment of the present invention;

3b : an enlarged view of the current input area for the in 3a illustrated dual mass flywheel;

3c : a schematic representation of an inventively designed spline for the in 3a shown dual mass flywheel in a schematic sectional view and

3d : in supervision

4a a schematic representation of a third preferred embodiment of the present invention;

4b : A schematic representation of an inventively designed hub disc for in 4a shown dual mass flywheel in a schematic sectional view

5a a schematic representation of a fourth preferred embodiment of the present invention;

5b : an enlarged view of the current input area for the in 5a illustrated torque transmitting device;

5c : a schematic representation of an inventively designed drive plate for in 5a illustrated torque transmitting device in a schematic sectional view;

6a a schematic representation of a fifth preferred embodiment of the present invention;

6b : an enlarged view of the current input area for the in 6a illustrated dual mass flywheel;

6c : a schematic representation of an inventively designed sprocket for in 6a shown dual mass flywheel in a schematic sectional view and

6d a schematic representation of an inventively designed dual mass flywheel housing for in 6a shown dual mass flywheel in a schematic sectional view.

As a result, identical or functionally identical elements are denoted by the same reference numerals.

1 schematically shows a current passage (arrows) by a torque transmitting device, which in the case shown as a torsion damper 100 is trained. The illustrated torsion damper 100 , but also every other torque transmission device has a drive side 102 and an output side 104 on. The drive side 102 has a with a combustion engine (not shown) rotatably connected cover 106 , for example, rotationally fixed by means of fasteners 108 can be fastened to a crankshaft of an internal combustion engine. The drive-side cover 106 is with a driven-side cover 110 rotatably connected, for example by welding. Furthermore, the torsional vibration damper comprises 100 , Spring elements 112 , which are designed in a known manner to compensate for torque irregularities.

A stream emanating from the internal combustion engine is via the housing element 106 over the spring elements 112 on cover plates 113 transfer. Through their direct contact and riveted joints 115 the electricity is applied to the hub disc 114 with hirth toothing 116 further introduced and thereby enters the transmission. Even if a contact point should have no direct contact with the current-conducting component, a current transition can occur due to sparking.

Such a current flow is shown schematically by the arrows. In particular, during the starting process of the vehicle can thereby be transmitted from the starter to the engine and to the transmission part of the flow. In this case, currents of about 30 amps and voltages of 12 to 14 volts can be achieved, can be welded together by the subsequent, mutually movable components. In particular, in automatic transmissions is the risk that a parking brake in the transmission loses its functionality.

According to the invention it is therefore proposed to provide in areas where there is no relative movement between components, one of the components with a coating which is electrically non-conductive, d. H. has a high electrical resistance. Due to the high electrical resistance, a current input to the non-rotatably connected element is prevented or allowed only to a small extent, so that subsequent components are protected from damaging current input.

Since the components are non-rotatably connected to one another, the mechanical load for the coating or the insulating element according to the invention is minimal, so that a current isolation over the life of the torque transmission device can be made possible.

The coating according to the invention may be ceramic or lacquer layers, wherein in particular the ceramic layers preferably consist of silicon oxide or of layers of chromium or chromium nitride-containing compounds or of an amorphous carbon structure. The coatings are preferably only a few micrometers thick, in particular between 2 and 50 microns, preferably between 3 and 30 microns thick.

In addition to the formation of a coating may alternatively or additionally also a separate insulating element made of an insulating material be used or a component made of an insulating material. In particular, it is conceivable to arrange plastic sleeves in rivet holes or to arrange plastic disks between components to be joined. Furthermore, ceramic components can also be used in the torque transmission element.

The 2 to 6 show various embodiments and possible arrangements for an electrical coating. Since the mode of operation of the torque transmission devices is not changed due to the coating according to the invention, the description of the function of the torque transmission devices will not be discussed further, but only the possible arrangements for the isolation elements and their mode of action will be described.

2 shows as a first embodiment, a torsion damper 100 with Hirth gearing, wherein 2a the torsion damper 100 as a schematic sectional view, 2 B the power input area and the 2c and 2d Detailed views. The in 2 shown torsion damper 100 corresponds to that already in connection with 1 Torsionsdämpfer discussed so that the description of the components is not discussed again.

A current input takes place in the illustrated torsion damper preferably in the rivets - see 2 B , According to the invention, therefore, the current insulation is made in this area. For this purpose, preferably the hub disc 114 in the area of the crowns - ie radially outward - are coated. Such a hub disc is shown schematically in FIG 2d in supervision and in 2c shown as a sectional view. Like that 2c and 2d can be seen, has the hub disc 114 in their radially outer region a coating 124 on, which provides an electrical insulation between the hub disc and the cover plates. In the schematic sectional view of 3b is continuing to see that the coating 124 around the entire crown area of the hub disc 114 extends and that also the rivet holes 118 with the coating according to the invention 124 can be coated.

Alternatively or additionally, at least one of the rivets 115 consist of an electrically insulating material or with an electrical insulation 124 be coated.

Another isolation point provides the teeth 116 itself. Here, the component, in this case the hub disc 114 , at least initially hardened in the toothed area or chemically nickel-plated or chrome-plated in order to protect it against wear. Thereafter, the insulating coating on the toothing 116 applied. In the in the 2a to 2d illustrated Hirth gearing 116 is also a coating of screws or screw holes 117 (please refer 2d ) advantageous.

Another embodiment of a torque transmitting element is in 3 - Partial figures 3a to 3d - shown. It shows 3a a sectional view through a dual mass flywheel 200 that a drive side 202 and an output side 204 having. The dual mass flywheel 200 has the drive side, a housing element 206 , which is rotatably connected to a motor and the output side, a secondary mass 208 on. In the in 4a illustrated embodiment has the illustrated dual mass flywheel 200 a spline 210 on, rotatably with the secondary mass 208 can be coupled. The rotationally fixed connection takes place by means of rivets 212 , As in the case of the torsional vibration damper described above, current insulation in the region of the rivets is also preferred 212 - see also the enlarged view of 3b ,

For electrical insulation between splines 210 and secondary mass 208 can the spline 210 at its radially outer region a coating according to the invention 224 which, as in the case previously described, in the region of the rivet holes 218 can be trained (see 3c and 3d ). In this case, the coating over the entire spline 210 However, it is also possible, the insulating coating 224 only in the area of the contact between splines 210 and secondary mass 208 train.

4 shows a further embodiment of a dual mass flywheel 200 in a schematic sectional view ( 4a ) and as a detail ( 4b ), in which the connection of the secondary mass 210 over a hub disc 214 he follows. Here is the secondary mass 210 and the hub disc 214 non-rotatable via riveted joints 212 connected.

In order to provide an electrical insulation between the drive side and the output side is in the in the 4a and 4b illustrated embodiment, the hub disc 214 in the area with an electrically insulating coating 224 provided in which they the secondary mass 210 contacted. This is clear in the presentation of 4b to see when the coating 224 in the area of contact points to the secondary mass 210 and in the area of the rivet hole 218 is arranged.

5 shows a further preferred embodiment, in which a torsional vibration damper 100 with a drive plate 300 a motor rotatably by means of rivets 315 connected is. In this case, the electrical insulation preferably takes place between the drive side and output side - ie before the entry of a current to the torsional oscillator 100 - And in the rivet connection 315 - see 5b , This is already before the torsion damper 100 prevented a current input, so that it is also ensured that moving elements in the torsional vibration damper 100 such as the feathers 112 not welded together due to the current input and lose their mobility.

In addition to electrical insulation of the rivets, it is also possible to use the drive plate 300 at their contact areas to the torsional vibration damper or other torque transmitting element with a coating 324 to be provided, advantageously also in the rivet holes 318 such a coating is provided. Such an embodiment is in 5c shown.

6 shows a further embodiment in which a torque transmitting element, such as a dual mass flywheel 200 , radially outside a sprocket 400 is attached, which is connectable to a starter (not shown). The current is applied at the point between the sprocket 400 and dual mass flywheel 200 , see detailed view 6b , This preferably shrunk gear ring 400 can do it on his own to the dual mass flywheel 200 side facing a coating of the invention 424 have, as in 6c shown. Additionally or alternatively, it is also possible that the torque transmission device 200 at its radially outer region where it the shrunk-on sprocket 400 contacted, with a coating 224 is provided. Such an embodiment is in 6d shown.

In addition to the illustrated in the embodiments preferred training options for an insulating coating according to the invention, other non-rotatably arranged to each other elements may have the coating of the invention. This can be done additionally or alternatively. Of course, all embodiments shown in the figures can be combined with each other, so that the embodiments shown in the figures can have multiple elements with an electrically insulating coating.

Overall, the electrical insulation according to the invention, which is arranged between two elements of a torque transmission device that are rotationally fixed relative to one another, constitutes a good and permanent insulation, so that a current input from an engine to the transmission during the starting process can be reliably prevented. As a result, the functionalities of the individual elements can be ensured and the service life of the components can be increased.

LIST OF REFERENCE NUMBERS

100

Dampers

102

driving side

104

output side

106

Drive-side housing section

108

drive connection

110

Output side housing section

112

spring element

113

Cover plate

114

hub disc

115

rivet

116

Hirth coupling

117

screw hole

118

rivet hole

124

coating

200

Dual Mass Flywheel

202

driving side

204

output side

206

Drive-side housing section

208

secondary mass

210

splines

212

rivet

214

hub disc

218

rivet hole

224

coating

300

drive plate

315

rivet

318

rivet hole

324

coating

400

sprocket

424

coating

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3721705 [0003]

Claims (23)

Torque transmission device, in particular for a motor vehicle, for transmitting a torque from a drive unit, in particular from an internal combustion engine, to an output unit, in particular a transmission, characterized in that at least one formed as an insulating element, an electrical continuity preventing torque transmitting device element ( 114 . 210 . 214 . 300 . 400 ) is provided, which is rotatably connected to an element to be insulated. Torque transmission device according to claim 1, characterized in that the at least one formed as an insulating torque transmitting device element at least partially at least one insulating coating ( 124 . 224 . 324 . 424 ) made of an electrically insulating material. Torque transmission device according to claim 2, characterized in that the at least one at least partially coating ( 124 . 224 . 324 . 424 ) is made of ceramic, in particular based on silicon oxide, chromium and / or chromium nitride. Torque transmission device according to claim 2 or 3, characterized in that the at least one at least partially coating ( 124 . 224 . 324 . 424 ) based on a preferably amorphous, carbon structure. Torque transmission device according to one of claims 2 to 4, characterized in that the at least one at least partially coating ( 124 . 224 . 324 . 424 ) is a lacquer layer. Torque transmission device according to one of claims 2 to 5, characterized in that the at least one at least partially coating ( 124 . 224 . 324 . 424 ) based on rubber or a rubber compound. Torque transmission device according to one of the preceding claims, characterized in that the insulation of the torque transmitting device element formed as an insulating element is formed in at least one contact region between the formed as an insulating torque transmitting device element and the element to be insulated. Torque transmission device according to claim 7, characterized in that the insulation is formed on the formed as an insulating torque transmitting device element in the range of at least one detachable and / or permanent connection between the formed as an insulating torque transmitting device element and the element to be insulated, in particular in the region of at least one riveted ( 115 . 212 . 315 ), and / or at least one gearing ( 116 ), and / or at least one plug connection, and / or at least one screw connection ( 117 ). Torque transmission device according to one of the preceding claims, characterized in that the torque transmitting device element designed as an insulating element comprises a coated rivet ( 115 . 315 . 212 ) and / or a coated rivet hole ( 118 . 218 . 318 ) and / or a coated rivet bearing surface, and / or a coated screw and / or a coated screw hole ( 117 ) and / or has a coated screw bearing surface. Torque transmission device according to one of the preceding claims, characterized in that the torque transmitting device element designed as an insulating element has a coated toothing ( 116 ) and / or having a coated tooth seat. Torque transmission device according to claim 10, characterized in that the formed as an insulating element torque transmitting device element, in particular the toothing ( 116 ) and / or the tooth seat, hardened and / or preferably chemically nickel-plated or chrome-plated and / or an insulating coating ( 124 . 224 . 324 . 424 ) having. Torque transmission device according to claim, characterized in that the at least one formed as an insulating torque transmitting device element is made of an electrically insulating material, in particular plastic and / or ceramic. Torque transmission device according to claim 12, characterized in that the torque transmitting device element formed as an insulating element as one of an opening, in particular a rivet hole ( 118 . 218 . 318 ) receiving sleeve is formed. Torque transmission device according to claim 12 or 13, characterized in that the formed as an insulating torque transmitting device element as a contact region between the formed as an insulating torque transmitting device element and the insulating element at least partially covering the insulating element, in particular as a disc is formed. Torque transmission device according to one of the preceding claims, characterized in that the torque transmission device, a clutch assembly, and / or a torsional vibration damper ( 100 . 200 ). Torque transmission device according to one of the preceding claims, characterized in that the torque transmission device is a torsional vibration damper ( 100 . 200 ) is associated with at least one of the drive side associated primary mass ( 106 . 206 ) and one of the driven side associated secondary mass ( 208 ), the non-rotatably preferably via riveted joints with a hub disc ( 114 . 214 ), wherein preferably formed as an insulating torque-transmitting device element, the hub disc ( 114 . 214 ). Torque transmission device according to claim 16, characterized in that the hub disc ( 114 . 214 ) at least partially the insulating coating ( 124 . 224 . 324 . 424 ), preferably at its radially outer region and / or in the rivet holes ( 118 . 218 ) and / or on the rivet supports and / or on the rivets and / or in the entire contact area between hub disc ( 114 . 214 ) and secondary mass ( 208 ). Torque transmission device according to claim 16 or 17, characterized in that the hub disc ( 114 . 214 ) Has rivets made of an electrically insulating material and / or received by the rivet holes sleeve-like insulation elements. Torque transmission device according to one of claims 16 to 18, characterized in that the torsional vibration damper ( 100 . 200 ) a spline ( 210 ) which at least partially isolates the insulating coating ( 124 . 224 . 324 . 424 ), preferably at their axial connection points and / or in the rivet holes ( 218 ) and / or at the riveting of the spline. Torque transmission device according to one of claims 16 to 19, characterized in that the torsional vibration damper ( 100 . 200 ) a gearing ( 116 ), in particular a Hirth toothing, which is chemically hardened, and / or nickel-plated or chrome-plated and / or with an electrically insulating coating ( 124 . 224 . 324 . 424 ), wherein preferably also the screws and / or the screw holes ( 117 ) of the Hirth toothing are coated. Torque transmission device according to claim 15, characterized in that the torsional vibration damper ( 100 . 200 ) radially outside a sprocket ( 400 ), which is designed to interact with a starter, wherein the sprocket ( 400 ) and / or the torsional vibration damper ( 100 . 200 ) is formed as an insulating element, wherein preferably an insulating coating ( 124 . 224 . 324 . 424 ) at the contact area between sprocket ( 400 ) and torsional vibration damper ( 100 . 200 ) is arranged. Torque transmission device according to one of claims 16 to 21, characterized in that the primary mass ( 206 ) at its contact area to a drive plate connected to the drive unit ( 300 ) the insulating coating ( 124 . 224 . 324 . 424 ) and / or coated rivet holes and / or coated rivets and / or rivets of an electrically insulating material and / or received by the rivet holes sleeve-like insulation elements. Torque transmission device according to one of the preceding claims, characterized in that the torque transmission device is rotatably connected to the drive unit drive plate ( 300 ), which at its output-side contact region an insulating coating ( 124 . 224 . 324 . 424 ) having.

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