DE102018119236A1 - TIMING BELT TENSION ARRANGEMENT WITH PRELOAD AND PROCEDURE - Google Patents

Abstract

A motor control drive tensioner assembly includes a tensioner having a tensioner housing having a mounting aperture and defining a cavity with a piston opening. A piston is housed in the cavity and a removable pin holds the piston in the cavity. The piston is configured to be pushed out of the piston opening when the pin is removed. The protuberance extends outwardly from the tensioner housing and is adapted to receive applied torque. The tensioner housing is configured to rotate about a central axis of the mounting aperture in response to a predetermined torque on the protuberance. One method of mounting a motor control gear includes applying a predetermined torque to a protuberance of a tensioner rotatably mounted on a cylinder block to rotate the tensioner toward a rotatable device such that the tensioner applies a predetermined load to the rotatable device.

Description

INTRODUCTION

In an engine timing drive, a rotatable member such as a chain or belt is connected to a crankshaft gear and camshaft gears to rotate the camshafts with the drive power of the crankshaft. The angular positions of the camshafts relative to the angular position of the crankshaft ensures that the opening and closing of the intake and exhaust valves occurs at the desired crankshaft positions. In addition, the camshafts may be controlled by cam phasers to vary the angular position of the camshafts relative to the crankshaft and thereby change the opening and closing of the valve. Proper control is maintained in part via a timing belt tensioner that provides tension despite expected wear of the chain or belt.

Achieving the desired valve timing is also dependent on the engine mounting method. In an index build-up assembly of the timing drive, the crankshaft and the camshafts are locked in known positions (eg, positions associated with top dead center) and then the timing drive components are assembled. The timing belt tensioner tension is only applied after the timing transmission components such as phaser, crankshaft sprocket, chain guides, and chain are installed. The tension in the chain, however, affects the final cam control.

SUMMARY

An engine control gear tensioner assembly and method of assembling a motor that allows the chain or belt to be biased with a tension that reduces sag caused by tightening the bolts of the camshaft adjuster, thereby ensuring that the control requirements be fulfilled. A tensioner assembly for a motor control gear includes a tensioner with a tensioner housing. The tensioner housing has a mounting aperture and defines a cavity with a piston opening. A piston is housed in the cavity and a removable pin holds the piston in the cavity. When the pin is removed, the piston is configured to be pushed out of the piston opening. The tensioner assembly also includes a protuberance that extends outwardly from the tensioner housing and is adapted to receive an applied torque. The tensioner housing is configured to rotate about a central axis of the mounting aperture when attached to the mounting aperture in response to a predetermined torque on the protuberance.

In one aspect of the disclosure, the tensioner housing includes a slot extending through the tensioner housing with the protuberance between the mounting aperture and the slot. The tensioner assembly may further include a dowel screw extending through the attachment opening and a locking bolt extending through the slot. The lock bolt enters the tensioner housing at one end of the slot to limit a range of movement of the tensioner housing about the dowel in response to the predetermined torque applied to the protuberance.

For example, the protuberance may have a side surface, such as, but not limited to, a hexagonal side surface adapted to fit in a torque wrench. A torque wrench may be applied to the protuberance and rotated to apply a predetermined torque to the tensioner housing, thereby causing the tensioner housing to rotate about the dowel and apply the predetermined load to an adjacent rotatable device such as a timing chain or timing belt , The predetermined torque may be selected such that the resulting given load is substantially equal to a load that prevents the rotation of the phaser when the camshaft adjustment bolts are tightened. The magnitude of the predetermined load is a function of the friction between the camshaft adjusting bolts and the phaser and between the phaser and the camshaft, this can be determined by a test. The tensioner housing can be held in the rotated position while the assembly of the timing gear is completed. In this way, the rotatable device is biased during assembly of the timing gear with the voltage in the rotatable device during assembly and thereby coincides with the voltage during engine operation. The final tightening of the timing drive components thereby does not cause sagging on the rotatable device, which might otherwise make it difficult to ensure that the desired relative rotational positions of the crankshaft sprocket and phaser are maintained, for example, during a net build process.

In one aspect of the disclosure, a first flange extends in a first direction from the tensioner housing, such as downwardly. The mounting hole is housed in the first flange. A second flange extends in a second direction from the tensioner housing against the first direction, such as upward. The slot is housed in the second flange.

In one aspect of the disclosure, the protuberance extends from an exterior of the tensioner housing, and an interior of the tensioner housing opposite the exterior is generally planar. For example, the inside may be adapted to face a cylinder block of the engine assembly.

In one aspect of the disclosure, the tensioner assembly may be in combination with a tensioner arm having a convex surface. A distal end of the piston extending from the cavity may have a convex distal surface configured to be connected to the convex surface of the tensioner arm when the tensioner housing is rotated about the central axis of the attachment aperture to the tensioner arm in response to the predetermined torque applied to the protuberance. The two convex surfaces may face each other across the range of motion of the tensioner housing because the tensioner housing is pivoted when the predetermined torque is applied to the protuberance, thereby preventing an abrupt impact on the tensioner arm by rotating the tensioner housing.

In one aspect of the disclosure, an engine assembly includes a cylinder block, a cylinder head resting on the cylinder block, and a crankshaft rotatably mounted on the cylinder block. The engine assembly includes at least one camshaft mounted on the cylinder head and a timing drive for controlling a relative angular position of the crankshaft and the at least one camshaft. The timing drive includes a rotatable device connected to the crankshaft and the camshaft. The rotatable device is either a chain or a belt. A tensioner arm is rotatably mounted on either the cylinder block or the cylinder head and configured to guide the rotatable device. The motor assembly also includes a tensioner assembly. The tensioner assembly includes a tensioner housing with a mounting aperture. The housing of the tensioner assembly has a cavity with a piston opening and a piston is housed in the cavity. A removable pin holds the piston in the cavity. The piston is configured to be pushed out of the piston opening when the pin is removed. The protuberance extends outwardly from the tensioner housing and is adapted to receive applied torque. The tensioner housing is rotatably mounted to the attachment opening on the cylinder block adjacent the tensioner arm and configured to rotate relative to the cylinder block to the tensioner arm in response to a predetermined torque applied to the protuberance such that the tensioner applies a predetermined load of the rotatable device applies over the tensioner arm.

In one aspect of the disclosure, the tensioner housing includes a slot extending through the tensioner housing with the protuberance between the mounting aperture and the slot. The tensioner housing includes a locking bolt attached to the cylinder block and extending through the slot. The lock pin enters the tensioner housing at one end of the slot to limit a range of movement of the tensioner housing in response to the torque applied to the protuberance.

In one aspect of the disclosure, a first flange extends in a first direction from the tensioner housing. The mounting hole is housed in the first flange. A second flange extends in a second direction from the tensioner housing counter to the first direction. The slot is housed in the second flange.

In one aspect of the disclosure, the protuberance extends from an exterior of the tensioner housing away from the cylinder block. An inside of the tensioner housing opposes the cylinder block and is generally flat. The tensioner arm may have an outer surface that faces the tensioner. A distal end of the piston has a convex distal surface configured to be connected to the outer surface of the tensioner arm when the tensioner housing is rotated toward the tensioner arm in response to the predetermined torque applied to the protuberance. The outer surface of the tensioner arm may be curved. For example, both the outer surface of the tensioner arm and the distal surface of the piston may be convex. This allows the two surfaces to couple over an entire range of motion of the tensioner when the piston applies the predetermined force to the tensioner arm, resulting in the predetermined load in the rotatable device.

One method of mounting a motor control gear includes applying a predetermined torque to a protuberance of a tensioner rotatably mounted on a cylinder block to rotate the tensioner toward a rotatable device such that the tensioner applies a predetermined load to the rotatable device. The rotatable device is either a chain or belt around a crankshaft wheel and at least one phaser. The method comprises further tightening a screw that holds the at least one camshaft adjuster to the camshaft. After tightening the screw, the method includes removing the predetermined torque from the protuberance of the tensioner. A locking bolt can then be tightened to secure the tensioner to the cylinder block. The predetermined load is the required load to prevent the rotation of the at least one camshaft adjuster by tightening the bolt.

For example, in one aspect of the disclosure, the method may further include releasing a locking pin on the tensioner such that a piston of the tensioner is biased toward the rotatable device to apply the predetermined load to the rotatable device.

Several additional aspects of the method may occur prior to application of the predetermined torque. For example, locking the crankshaft at a predetermined angular position relative to the cylinder block such that the crankshaft remains in angular position when the predetermined torque is applied and locking the camshaft at a predetermined position relative to a cylinder head mounted on the cylinder block to prevent rotation of the at least one camshaft phaser relative to the cylinder block occur prior to application of the predefined load. The method may include positioning the rotatable device about the crankshaft wheel and the at least one phaser. Further, the method may include mounting the tensioner to the cylinder block with a dowel screw such that the tensioner rotates about the dowel screw when the predetermined torque is applied. In addition, even before applying the predetermined torque and before tightening the locking bolt, the method may include inserting the locking bolt into the cylinder block through a slot in the tensioner. The slot and the locking pin are configured such that the locking pin abuts the end of the slot when the predetermined torque is applied. In one example, a fitter (or robot) applying the predetermined torque to the tie rod may perform these actions first. Alternatively, the engine assembly may be sent to a final assembly destination where torque must be applied to the protuberance if one or more of these actions have already been performed.

The foregoing functions and advantages, as well as other features and advantages of the present disclosure, will be apparent from the following detailed description of the best mode of practicing the illustrated disclosure, taken in conjunction with the accompanying drawings.

list of figures

• 1 is a schematic representation of a partial perspective view of a motor assembly with a timing drive having a tensioner assembly within the scope of the present disclosure.
• 2 is a schematic representation of a perspective view of a motor-facing side of the timing drive and the tensioner assembly 1 ,
• 3 is a schematic representation of a partial perspective view of the motor assembly with the timing drive and the tensioner assembly 1 showing the tensioner assembly prior to application of applied torque.
• 4 is a schematic representation of a perspective partial view of the motor assembly with timing drive and tensioner assembly 3 which outlines a torque wrench applying torque to a torque receiving feature of the tensioner assembly.
• 5 is a schematic representation in perspective view of the tensioner assembly 1 ,
• 6 is a schematic representation of a partial view of the front end of the tensioner, which is attached to the cylinder block and from which the piston is removed.
• 7 FIG. 10 is a flowchart of a method of assembling a motor control drive. FIG.

DETAILED DESCRIPTION

Referring to the drawings wherein like reference numerals refer to like components in the views, FIG 1 a motor assembly 10 with a timing drive 12 that a tensioner arrangement 13 with a tensioner 15 includes. The engine arrangement 10 includes a cylinder block 14 and a cylinder head 16 standing on the cylinder block 14 rests. A crankshaft 18 is rotatable on the cylinder block 14 stored. At least one camshaft is on the cylinder head 16 assembled. In the illustrated embodiment, an intake camshaft 20A and an exhaust camshaft 20B configured to open and close the intake and exhaust valves.

The tax drive 12 Controls the relative angular position of the crankshaft 18 and the camshafts 20A . 20B , The tax drive 12 includes a rotatable device 22 ready with the crankshaft 18 and the camshafts 20A . 20B connected is. The rotatable device 22 can be a chain or a belt. The rotatable device 22 may be referred to herein for purposes of discussion as a chain; However, it is understood that the rotatable device 22 a belt can be. The chain 22 is ready for operation with a crankshaft wheel 24 connected, firmly with the crankshaft 18 via one or more crank pins 26 is mounted, so that the gear 24 with the crankshaft 18 rotates. The chain 22 is ready for operation with camshaft gears 28A . 28B connected in the camshaft adjuster 27A , respectively. 27B are installed. The camshaft adjuster 27A . 27B are on the camshafts 20A , respectively. 20B mounted, each with one or more camshaft adjuster bolts, such as the bolts 30A . 30B , The camshaft adjuster 27A . 27B are controlled by an engine control unit (not shown) via oil pressure or otherwise to control the angular position of the camshafts 20A . 20B in relation to the respective gears 28A . 28B to vary. As a result, the control of the intake and / or exhaust valve opening changes in relation to the crankshaft position.

Other timing transmission components include one or more chain guides 36 and a tensioner assembly 13 with a tensioner arm 32 (also referred to as tensioner guide), the chain 22 leads and rotatable on the cylinder head 16 with a bolt 34 or another attachment is attached, so that the tensioner arm 32 over a rotation axis P1 turns, and is configured, the chain 22 as well as the piston 52 the tensioner assembly 13 to guide them on the chain 22 , as described here, act. The tensioner arm 32 turns around its axis of rotation P1 and moves to the chain guide 36 when the tensioner 15 the chain 22 over the tensioner arm 32 loaded, resulting in a load (ie a tensile force) in the chain 22 results. The tensioner arm 32 thus leads the chain 22 between the crankshaft 24 and the camshaft wheel 28B , Although as a cylinder head 16 shown mounted, in other embodiments, the tensioner arm 32 shorter and on the cylinder block 14 instead of the cylinder head 16 to be appropriate.

Another chain guide 36 is on the cylinder head 16 with a bolt 38 and also on the cylinder block 14 with a bolt 40 attached. The chain guide 36 leads the chain 22 between the camshaft sprocket 28A and the crankshaft gear 24 ,

It is understood that screws or other fasteners described herein that are operable to attach to components of the cylinder block 14 or the cylinder head 16 to assemble, with appropriate mounting holes in the cylinder block 14 or the cylinder head 16 work together and can be threaded or not.

The tensioner arrangement 13 is configured the chain 22 During engine mounting, use a load to preload on the chain 22 through the tensioner 15 over the tensioner arm 32 is applied, which is substantially equal to the load, by tightening the screws of the camshaft adjuster 30A and 30B is applied. The substantially same magnitude of preload prevents the chain from sagging during assembly and ensures that the assembly of the motor and timing drive components best achieves the desired control.

With reference to 5 and 6 includes the tensioner 15 a tensioner housing 44 , which is a first flange 45 with a mounting hole 46 has that extends through there. A fitting screw 48 extends through the mounting hole 46 and has an end that can be threaded and on the cylinder block 14 may be attached to the tensioner housing 44 rotatable on the cylinder block 14 to fix. In other words, the tensioner housing 44 can be relative to the cylinder block 14 around the dowel screw 48 rotate (ie, around the central axis 47 the mounting hole 46 ).

The tensioner housing 44 also defines a cavity 55 with a piston opening 50 that in general to the chain 22 shows how it looks 1 and 6 can be read out when taken together. A generally cylindrical piston 52 is in cavity 55 accommodated. A removable locking pin 42 in 3 Holds the piston 52 in the cavity 55 to prevent the piston 52 further out of the opening 46 by a biasing element, such as pressurized oil and / or a spring in the cavity 55 is pushed outward. When the locking pin 42 is removed, the biasing force of the biasing member presses the piston 52 out of the opening 50 further out and against the adjoining tensioner arm 32 , and applies a predetermined force to the arm 32 at, resulting in a given load L in the chain 22 leads, as described herein.

The tensioner housing 44 includes a protuberance 54 extending from an outside 56 the tensioner housing 44 away from the cylinder block 14 extends to the outside. An inside 57 the tensioner housing 44 is basically flat and in 2 and 6 to see. The inside 57 is configured to fit the cylinder block 14 opposite when the tensioner 15 on the cylinder block 14 is attached as it is in 6 is shown.

The protuberance 54 is adapted to receive an applied torque from a torque tool. For example, as in 5 shown, the protuberance 54 a hexagonal side surface 60 that is adapted to fit in a torque wrench 62 to fit, which is shown in dashed lines, wherein the predetermined torque T on the protuberance 54 in 4 is applied. The tensioner housing 44 turns in relation to the cylinder block 14 in the direction of the tensioner arm 32 in response to a predetermined torque T, which depends on the protuberance 54 is applied, so the tensioner 15 (more precisely, the piston 52 ) a predetermined force F on the chain 22 exerts over the tensioner arm, resulting in the predetermined tensile load L on the chain 22 leads. The predetermined force F gives a predetermined load L (ie, tensile load L in the chain 22 , also referred to as traction L, in 4 is shown). The magnitude of the predetermined load is a function of the friction between the camshaft adjusting bolts 30A . 30B and the phaser 28A . 28B and between the phaser and the camshaft 20A . 20B This can be determined by an examination. Turning the tensioner housing 44 is by comparing the position of the tensioner 44 in 3 in relation to the position in 4 clear. The position of the tensioner housing 44 before application of the predetermined torque is by the angle A1 the central axis C of the piston 52 and the cavity 55 to the horizontal H indicated. The position of the tensioner housing 44 using the predetermined torque T is through the angle A2 the central axis C of the piston 52 and the cavity 55 to the horizontal H indicated.

With reference to 5 and 6 includes the tensioner housing 44 a second flange 63 moving in a second direction D2 from the tensioner housing 44 with a slot 64 which passes through there extends. The protuberance 54 lies between the mounting hole 46 and the slot 64 , The tensioner arrangement 13 includes a locking bolt 66 on the cylinder block 14 is attached and through the slot 64 extends. The second direction D2 is opposite to the first direction D1 , in which the first flange 45 extends. For example, the first direction D1 generally directed downwards and the second direction D2 is generally directed upwards when the tensioner 15 on the cylinder block 14 is mounted. The first direction D1 is orthogonal to the central axis C of the piston 52 and the cavity 55 is generally directed down and the second direction D2 is orthogonal to the central axis C of the piston 52 and the cavity 55 in a generally upward direction. A central axis 49 the protuberance 54 is orthogonal to the central axis C of the piston 52 and the cavity 55 , orthogonal to the first direction D1 the first flange 45 and orthogonal to the second direction D2 the second flange 63 , Accordingly, the central axis 47 the first opening 46 and the dowel screw 48 , the central axis 49 the protuberance 54 and the central axis 51 of the locking bolt parallel.

How best in 2 shown is the slot 64 elongated relative to the diameter of the part of the locking bolt 66 that goes through the slot 64 extends. When the torque T, as described, is applied and assuming that the locking bolt 66 not yet tightened, so that the second flange 63 not tight between the locking bolt 66 and the cylinder block 14 held, the tensioner housing can 44 in relation to the fixed locking bolt 66 move. More specifically, the length of the slot allows 64 a range of motion of the tensioner housing 44 between a first position in 3 , before application of the applied torque T, and a second position in 4 when the torque T is applied. The first position in 3 is determined by the interference of the shaft portion of the locking bolt 66 with a first end 70 (in 4 shown) of the slot 64 (ie a proximal end, that of the chain 22 is closest). The second position in 4 is determined by interference of the shaft portion of the locking bolt 66 with a second end 72 (in 3 shown) of the slot 64 (ie a distal end furthest from the chain 22 away). The locking bolt 66 interferes with the tensioner housing 44 at both ends of the slot 64 to a range of motion of the tensioner housing 44 , in response to the torque applied to the protuberance 54 , to limit.

The piston 52 and the tensioner arm 32 are configured cooperatively so that their interface does not have the capability of the tensioner housing 44 hinders turning under the applied torque T. For example, the interfering surfaces may be curved to reduce friction when rotating the tensioner 15 to minimize. As in 3 showed the tensioner arm 32 a convex outer surface 74 to the tensioner 15 shows. As in 3 and 5 shown has a distal end 76 of the piston 52 a convex distal surface 78 , The distal surface 78 is configured with the convex outer surface 74 the tensioner arm 32 to be connected, both when the tensioner housing 44 on the cylinder block 14 prior to application of the applied torque T (ie, in the first position in FIG 3 ) and if the tensioner housing 44 to the tensioner arm 32 is rotated, in response to the predetermined torque T, that on the protuberance 54 is applied (ie in the second position in 4 ). This allows the two surfaces 74 . 78 over an entire range of motion of the tensioner 15 to connect when the piston 52 the predetermined force F on the tensioner arm 32 exercises. The two convex surfaces 74 . 78 stand each other over the range of motion of the tensioner housing 44 and thus prevent an abrupt impact on the tensioner arm 32 by turning the tensioner housing 44 ,

The tensioner housing 44 can in the rotated position in 4 through the torque wrench 62 are held while the assembly of the other timing drive components is completed. That way, the chain becomes 22 when assembling the timing gear 12 with the tension in the chain 22 biased during assembly, this is essentially equal to the tension in the chain 22 during subsequent engine operation. The final tightening of the timing drive components thereby causes no sagging of the chain 22 What else could make it difficult to ensure that the desired relative rotational positions of the crankshaft 24 and the camshaft adjuster 27A . 27B , while maintaining a net build process.

In accordance with the above-described tensioner 15 and tax drive 12 , shows 7 a flowchart of a method 100 for mounting a motor control drive 12 , The procedure 100 starts with several actions that precede the chain 22 expire. For example, in block 102 the crankshaft 18 locked at a predetermined rotational position. Those skilled in the art are aware of various ways of locking a crankshaft. For example, a mark on the crankshaft 18 be aligned with a mark on the cylinder block 14 to ensure a predetermined rotational position, such as top dead center. Locking the crankshaft 18 can then be achieved by a tool, such as a pin, through an access opening in a bell crank, which surrounds a flex plate, is plugged so that the tool rests against the flex plate on the crankshaft 18 is mounted.

Likewise are in block 104 , the camshafts 20A . 20B each locked in a predetermined rotational position, such as by aligning the indicator marks on the camshaft 20A . 20B at the indicator marks on the cylinder head 16 , and passing a corresponding tool, such as a pin, through an aperture in each camshaft 20A . 20B , The tool hits the cylinder head 16 or another non-rotatable member to rotate the camshafts 20A . 20B to prevent.

Next are in block 106 the camshaft adjuster 27A . 27B and the tensioner 15 Loosely mounted, as by attaching the camshaft adjuster 27A . 27B with the camshaft gears 28A . 28B on the camshafts 20A . 20B without the screws 30A . 30B completely put on. Likewise, block 106 the also loose assembly of the tensioner 15 on the cylinder block 14 include, without the dowel screw 48 fully tighten with a final, predefined torque. For example, each of the assembly tasks in block 106 be carried out by hand.

Next, in block 108 the locking bolt 66 through the slot 64 in the tensioner housing 44 and in the cylinder block 14 be plugged, but without the locking bolt 66 fully tighten so that the tensioner housing 44 in relation to the cylinder block 14 and the dowel screw 48 , as described herein, can be rotated.

In block 110 For example, the control drive components may be assembled as by attaching the tensioner arm 32 on the cylinder head 16 , by attaching the chain guide 36 on the cylinder head 16 and the cylinder block 14 , by attaching the crankshaft sprocket 24 on the crankshaft 18 and arranging the chain 22 around the camshaft gears 28A . 28B and the crankshaft wheel 24 ,

In block 112 can the tensioner 13 be arranged, such as by positioning the tensioner housing 44 in the first position in 3 with the locking bolt 66 at the end 70 of the slot 64 , The fitting screw 48 can then in block 114 be attracted. Also with the completely on the cylinder block 14 tightened fitting screw 48 , the tensioner housing 44 around the dowel screw 48 to be turned around

The tax drive 12 is now ready for the bias of the chain 22 in block 116 by applying the predetermined torque T to the protuberance 54 with the torque wrench 62 to the tensioner 15 to the chain 22 to turn, so the tensioner 15 the given load L on the chain 22 applies (over the piston 52 , who deals with the tensioner arm 32 links). Next will be in block 118 the camshaft bolt 30A . 30B after each other or tightened together using a multi-axis tool. Due to the bias on the chain 22 causes the tightening of the screws 30A . 30B no sagging of the chain, what else for a correct installation of the relative rotational positions of the crankshaft 18 and the camshafts 20A . 20B would have to be considered.

The locking bolt 66 will be in the block 120 Attracted to the tensioner 15 on the cylinder block 14 to fix. Once the camshaft bolt 30A . 30B and the locking bolt 66 be attracted, in the block 122 the predetermined torque T from the protuberance 54 the tensioner housing 44 Taken by the torque wrench 62 Will get removed. The locking pin 42 will be in the block 124 released (ie removed), leaving the biasing element within the tensioner 13 the piston 52 against the chain 22 biases. The camshafts 20A . 20B and the crankshaft 18 are then unlocked so that they can rotate, they do so according to the desired relative control.

While the best modes for carrying out the disclosure have been described in detail, those familiar with the art described herein will recognize various alternative designs and embodiments with which the disclosure may be practiced within the scope of the following claims.

Claims (10)

A tensioner assembly for a motor control gear comprising the tensioner assembly: a tensioner including: A tensioner housing having a mounting aperture defining a cavity with a piston opening; a piston disposed in the cavity and a removable pin holding the piston in the cavity, wherein the piston is configured to be pushed out of the piston opening when the pin is removed; and a protuberance extends outwardly from the tensioner housing and is adapted to receive an applied torque; wherein the tensioner housing is configured to rotate about a central axis of the attachment opening when attached to the attachment opening in response to a predetermined torque on the protuberance. The tensioner arrangement according to Claim 1 wherein the tensioner housing includes a slot extending through the tensioner housing with the protuberance between the mounting aperture and the slot. The tensioner arrangement according to Claim 2 further comprising: a dowel screw through the attachment opening; and a locking bolt extending through the slot; wherein the locking bolt goes into the tensioner housing at one end of the slot to limit a range of movement of the tensioner housing about the dowel in response to the predetermined torque applied to the protuberance. The tensioner arrangement according to Claim 2 wherein: a first flange extends in a first direction from the tensioner housing; the attachment opening is in the first flange; a second flange extending in a second direction from the tensioner housing opposite to the first direction; and the slot is in the second flange. The tensioner arrangement according to Claim 1 wherein a side surface of the protuberance is hexagonal. The tensioner arrangement according to Claim 1 wherein the protuberance extends from an outside of the tensioner housing; and wherein an inside of the tensioner housing is generally planar with respect to the outside. The tensioner arrangement according to Claim 1 in combination with a tensioner arm with a convex surface; wherein a distal end of the piston extending from the cavity has a convex distal surface configured to be connected to the convex surface of the tensioner arm when the tensioner housing is rotated about the central axis of the attachment aperture to the tensioner arm in response to the predetermined torque applied to the protuberance. A method of assembling a motor control drive, the method comprising: applying a predetermined torque to a protuberance of a tensioner rotatably mounted on a cylinder block to rotate the tensioner toward a rotatable device such that the tensioner applies a predetermined load to the rotatable device; wherein the rotatable device is either a chain or a belt positioned about a crankshaft wheel and about at least one phaser; Tightening a screw that holds the at least one camshaft adjuster to the camshaft; Removing the predetermined torque from the protuberance of the tensioner; and Tightening a locking bolt to secure the tensioner to the cylinder block. Method according to Claim 8 further comprising: releasing a locking pin on the tensioner such that a piston of the tensioner is biased toward the rotatable device. Method according to Claim 8 , further comprising: before applying the predetermined torque, mounting the tensioner on the cylinder block with a dowel screw, so that the tensioner around the The fitting screw turns when the specified torque is applied.

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