KR20190073491A - Tensioner - Google Patents

Abstract

The tensioner includes a base, a first pivot arm pivotably engaged with the base, a first pulley journalled to the first pivot arm, a second pivot arm pivotably engaged with the base, A journaled second pulley, a toothed engagement with the first pivot arm, and a toothed engagement with the second pivot arm such that the first pivot arm and the second pivot arm move in a coordinated manner A tensioning member, and a tensioner assembly that pivotably engages the base and engages the flexible tensioning member.

Description

Tensioner

The present invention relates to a tensioner, and more particularly to a tensioner comprising a first pivot arm and a second pivot arm mounted on a base, a second pivot arm mounted to the base for retracting between the first pivot arm and the second pivot arm to move in a coordinated manner, And a tensioner assembly having a tensioner assembly mounted to the base and engaged with the flexible member.

In most belt drive applications, the ability to maintain adequate belt tension is important in ensuring that the belt transmits power without slipping. The minimum tension span in the belt drive is usually referred to as the slack side span. The tensioner is typically positioned on the relief side span of the belt drive and assumes the task of maintaining the appropriate minimum belt tension in this span. Using the direction of belt rotation as an indicator, this span is in this case the span located immediately after the power-providing pulley or crankshaft. For example, when the crankshaft rotates, the relaxed side span will be the span where the belt is just passing through the crankshaft pulley, and the tight side span will be the span approaching the crankshaft pulley.

The Belt Alternator Starter (BAS) utilizes an alternator that also functions as a motor. This is often referred to as a motor-generator. The operation of the BAS system is such that the alternator behaves in a predominant manner when the engine is operating and is subjected to a constant load and to be loaded by the alternator with the belt being powered by the engine crankshaft pulley. In the BAS system, the drive is typically configured to position the alternator as the next accessory after the belt has passed the crankshaft. In this configuration, the belt tensioner must be positioned between the crankshaft pulley and the alternator. The tensioner is positioned just before the alternator using the belt rotation direction as an indicator.

The BAS system causes inherent problems with the belt drive. The alternator serves as a load for the belt drive and a power supplier for the belt drive. The BAS system alternator is used to start the engine, and the alternator is used to power the engine. At startup, the alternator pulley is the power provider for the drive. This typically converts the position of the relaxation side span in the drive to a span subsequent to the alternator pulley. In addition, the tension side span is now the span between the alternator and the crankshaft. Since conventional tensioners are configured to simply keep the minimum level of relaxed side tension, the present high tension at the tensioner position in the belt causes an extreme shift of the tensioner. Additionally, this situation creates a demand for a second tensioner at a location on a new relaxation side span.

A conventional approach to solve this problem is to form a belt drive with two tensioners. This second tensioner is typically a tensioner with high resistance to movement away from the belt. The second tensioner is often an expensive hydraulic tensioner. These two tensioner configurations also require an excessively long belt to accommodate multiple tensioners in the drive. As a result, the solution is usually expensive.

U.S. Patent No. 7,494,434, which discloses an auxiliary drive for an engine having a belt-driven starter generator adapted to drive or be driven by an engine, is a representative technique. In an exemplary embodiment, the drive includes a first engine drive pulley and a second starter drive pulley. The drive belt engages the drive pulleys to drive either pulley from the other pulley. A dual belt tensioner, formed as an example assembly unit, has a central pivot portion mounted to the engine and a carrier having a first carrier arm and a second carrier arm extending radially from the central pivot portion. The first tensioner mounted on the first arm carrier is relaxed during engine starting and carries a first tensioner pulley which is urged against a first belt extending adjacent to the second drive pulley. The second tensioner pulley carried on the second arm carrier is tensioned during engine starting and is urged against a second belt extending adjacent to the second drive pulley. The hydraulic struts connected to the second arm carrier, and preferably included in the preassembled unit, are normally sensitive to the pressure on the second tensioner pulley and the increased belt force during normal engine operation, Limiting the reactive motion of the second tensioner pulley during operation.

A first pivot arm and a second pivot arm mounted on the base, a flexible member which is pulled between the first pivot arm and the second pivot arm so as to move in a coordinated manner, A tensioner with a tensioner assembly is required. The present invention meets this need.

A main aspect of the present invention is a pneumatic tire comprising a first pivot arm and a second pivot arm mounted on a base, a flexible member being pulled between the first pivot arm and the second pivot arm to move the pivot arms in a coordinated manner, And to provide a tensioner having a tensioner assembly that engages the flexible member.

Other aspects of the present invention will become apparent or obvious from the following detailed description of the invention and the accompanying drawings.

The present invention relates to a pivot arm having a base, a first pivot arm pivotably engaged with the base, a first pulley journalled to the first pivot arm, a second pivot arm pivotably engaged with the base, A second pulley, a toothed engaging portion with the first pivot arm, and a toothed portion with the second pivot arm such that the first pivot arm and the second pivot arm move in a coordinated manner A tensile member, and a tensioner assembly that pivotably engages the base and engages the flexible tension member.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and, together with the description, serve to explain the principles of the invention.
1 is a perspective plan view of a device.
Figure 2 is a cross-sectional view of the device.
3 is an exploded view of the device.
Figure 4 is a detailed view of the damping assembly.
Figure 5 is an exploded view of the damping assembly of Figure 4;
Figure 6 is a detailed view of the damping assembly.
Figure 7 is an exploded view of the damping assembly of Figure 6;
8 is a perspective plan view of the synchronous tensioner assembly.
Figure 9 is an exploded view of the synchronous tensioner assembly of Figure 8;
10 is an exploded view of an idler assembly.
11 is an exploded view of an idler assembly.
12A is a detailed view of the pivot arm.
12B is a detailed view of the pivot arm.
13A is a detailed view of the pivot arm.
13B is a detailed view of the pivot arm.
14 is a perspective view of the inside of the device.
15 is a detailed view of a device in an operating position on the engine.
16 is a view showing the orientation and hub load of the pivot arm 5 and the pivot arm 55 at the rest position.
17A is a detailed view of pivot arm loading conditions.
17B is a detailed view of the pivot arm load condition.
18 is a view showing the orientation and hub load of the pivot arm 5 and the pivot arm 55 at the alternator startup mode position.
19 is a detailed view of the clutch spring.
20 is a detailed view of the clutch spring.
21 is a detailed view of the base.
22A is a diagram illustrating the position of a pivot arm in an operating state.
22B is a view illustrating the position of the pivot arm in the operating state.
22C is a view illustrating the position of the pivot arm in the operating state.
22D is a view illustrating the position of the pivot arm in the operating state.
Figure 23 is a bottom view of the tensioner assembly of Figure 8;
24 is a detailed view of the tensioner spring.
25 is a detailed view of the base.
26 is a detailed rear view of the tensioner mounted on the alternator;
27 is a detailed rear view of the tensioner mounted on the alternator.
28 is a bottom view of the tensioner arm;
29 is a perspective view of sections 29-29 from FIG.
30 is a perspective view of a modified example.
31 is a plan view of the embodiment of Fig.
32 is an exploded view of the embodiment of Fig.
33 is a cross-sectional view of the embodiment of Fig.
34 is a side view of the eccentric arm cam;
Figure 35 is a perspective view of the arm of Figure 34;
FIG. 35A is a perspective view of the arm of FIG. 34; FIG.
Figure 36 is a perspective view of the arm of Figure 37;
Fig. 36A is a perspective view of the arm of Fig. 37;
37 is a side view of the eccentric arm cam.
38 is a side view of the eccentric upper arm.
39 is a perspective view of the arm of Fig.
40 is a side view of the eccentric upper arm.
41 is a perspective view of the arm of Fig.
Figure 42 is a side cross-sectional view of the embodiment of Figure 31;
43 is a detailed view of the idler assembly.
Figure 44 is a detailed view of the damping mechanism for the embodiment of Figure 30;
45 is a view showing a damping mechanism for the embodiment of FIG. 30. FIG.
Figure 46 is a cross-sectional view of the embodiment of Figure 31;
Figure 47 is a detail view of the base of the embodiment of Figure 30;
Figure 48 is a detail view of the spring of the embodiment of Figure 30;
Figure 49 is a detail view of the spring of the embodiment of Figure 30;
Figure 50 is a plan view of the tensioner of the embodiment of Figure 30;
51 is a side view of the tensioner of Fig.
52 is a side view of the tensioner of Fig.
53 is a cross-sectional view of the tensioner of Fig.
54 is an exploded view of the tensioner of Fig.
FIG. 55 is a detailed view of the base of FIG. 47; FIG.
FIG. 56 is a detailed view of the base of FIG. 47; FIG.
FIG. 57 is a detailed view of the base of FIG. 47; FIG.

1 is a perspective plan view of a device. The tensioner 1000 of the present invention includes a first tensioner assembly 501 and a second tensioner assembly 502 pivotally mounted to the base 1, respectively.

2 is a cross-sectional view of the device. A shaft (2) and a shaft (22) are extended from a base (1). The pivot arm 5 is pivotally journaled to the shaft 2 via a bushing 6. The pivot axis of the pivot arm (5) is coaxial with the shaft (2). The pivot arm 55 is pivotally journaled to the shaft 22 through a bushing 66. The pivot axis of the pivot arm (55) is coaxial with the shaft (22). The shaft 2 and the shaft 22 are not coaxial. The pivot axis of the arm (5) is not coaxial with the pivot axis of the arm (55).

The clutch spring 3 is engaged between the damping assembly 4 and the base 1. A clutch spring 33 is engaged between the damping assembly 44 and the base 1. The pulley 101 is journaled to the pivot arm 55 through the bearing 102. The pulley 10 is journaled to the pivot arm 5 via the bearing 12. The clutch spring 3 and the clutch spring 33 are used to activate the damping function.

The fastener (14) and the fastener (144) hold the cover (9) on the base (1). The arm 5 is held on the base 1 by the retaining ring 7. The tensioner assembly 15 is held on the base 1 by a cover 9. The cover 9 protects the internal components from debris.

3 is an exploded view of the device. The washer 120 is disposed between the retaining ring 7 and the bushing 6. The washer 122 is disposed between the retaining ring 77 and the bushing 66. The arm 5 pivots about the bushing 6 and the bushing 661. The arm 55 pivots about the bushing 660 and the bushing 66. The fastener (13) is engaged with the arm (5). The fastener 133 is engaged with the arm 55.

Figure 4 is a detailed view of the damping assembly. Figure 5 is an exploded view of the damping assembly of Figure 4; The damping assembly 4 includes a damping shoe 41 and a damping ring 42. The damping ring 42 is coaxial with the damping shoe 41. The damping ring 42 has a cylindrical shape with a gap 421 in the axial direction. The damping ring 42 has a plurality of inwardly projecting tabs 420, 430 to receive the damping shoe. The damping shoe has a cylindrical shape with a gap 410 in the axial direction. The outer surface 422 of the damping ring 42 is frictionally engaged with the inner surface 51 of the pivot arm 5.

Figure 6 is a detailed view of the damping assembly. Figure 7 is an exploded view of the damping assembly of Figure 6; The damping assembly 44 includes a damping shoe 441 and a damping ring 442. The damping ring 442 is coaxial with the damping shoe 441. The damping ring 442 is of a cylindrical shape with the gap 4440 extending in the axial direction. The damping ring 442 has a plurality of tabs 4420, 4430 projecting inwardly to receive the damping shoe 441. The damping shoe 441 is a cylindrical shape in which the gap 4410 extends in the axial direction. The outer surface 4421 of the damping ring 442 is frictionally engaged with the inner surface 551 of the pivot arm 55.

8 is a perspective plan view of the tensioner assembly. Figure 9 is an exploded view of the tensioner assembly of Figure 8; The synchronous tensioner assembly 15 includes a rotary belt guide 151, a fastener 152, an arm 153 and a spring 154. The belt guide 151 is journaled to the arm 153 by a shaft 155. The shaft 155 is engaged with the hole 1532 in the arm 153. The arm 153 is pivotally attached to the base 1 by a fastener 152. The spring 154 is fixedly attached to the arm 153 by a tab 1530 and a tab 1531 (see FIG. 28). The spring 154 acts as an urging member for applying a load to the belt 9 by applying torque to the arm 158. Figure 23 is a bottom view of the tensioner assembly of Figure 8; 24 is a detailed view of the tensioner spring. 25 is a detailed view of the base. Spring end 1540 engages between tab 912 and tab 913 in base 1, which prevents the spring from rotating when subjected to a load (see Figures 21 and 25).

The shaft (2) is fixedly attached to the base (1). The clutch spring 3 is fixedly attached to the base 1 through a tang which engages the slot 911 of the base 1 (see Figs. 19 and 21). The pivot arm 5 and the bushing 6 and the bushing 661 are journaled to the shaft 2 through the bore 54. [ The washer 120 is coaxial with the shaft 2. The retaining ring (7) is fixedly positioned on the shaft (2) in the groove (21). The damping assembly 4 is coaxial with the pivot arm 5.

The shaft 22 is fixedly attached to the base 1. The clutch spring 33 is attached to the base 1 via a tang 331 engaged with the slot 910 (see Figs. 20 and 21). Pivot arm 55 and bushing 66 and bushing 660 are pivotally attached to shaft 22 through bore 554. The washer 122 is coaxial with the shaft 22. The retaining ring (77) is fixedly positioned on the shaft (22) in the groove (221). The retaining ring (7) holds the arm (5) on the shaft (2). The retaining ring (7) is fixedly positioned on the shaft (2) in the groove (21). The retaining ring (77) holds the arm (55) on the shaft (22). The damping assembly 44 is coaxial with the pivot arm 55. The damping assembly 44 frictionally engages the pivot arm damping surface 551.

10 is a detailed view of an idler assembly. 11 is a detailed view of an idler assembly. The pulley 10 is journaled to the bearing 12. The bearing 12 is journaled to the pivot arm 5 on the surface 53. The pulley 101 is journaled to the bearing 102. The bearing 102 is journaled to the pivot arm 55 on the surface 553.

12A is a detailed view of the pivot arm. 12B is a detailed view of the pivot arm. 13A is a detailed view of the pivot arm. 13B is a detailed view of the pivot arm. The pivot arm bearing mounting surface 53 receives the bearing 12 and is not coaxial with the pivot arm bore 54 (see bearing axis A and pivot axis B, respectively). The pivot arm bearing mounting surface 553 receives the bearing 102 and is not coaxial with the pivot arm bore 554. [ The bore 54 engages with the shaft 2 which receives the fastener 13. The bore 554 engages the shaft 22 that receives the fastener 133.

The pivot arm (5) pivots about the pivot axis (A). The bearing 12 rotates about the bearing axis B. The bearing axis B and the pivot axis A are not coaxial, but instead offset from each other by a predetermined distance x.

The pivot arm 55 pivots about the pivot axis A2. The bearing 102 rotates about the bearing axis B2. The bearing axis B2 and the pivot axis A2 are not coaxial but instead offset from each other by a predetermined distance y.

The belt 8 is engaged with the sprocket 52 on the pivot arm 5 and the sprocket 552 on the pivot arm 55, respectively. The belt 8 may be toothed, but may also include any flexible member suitable for supporting a tensile load. Sprocket (52) and sprocket (552) are toothed to engage actively on belt (8).

14 is a perspective view of the inside of the device. The belt (8) engages the tensioner assembly (15). All tensile loads on the belt 8 and the belt 200 are imparted by the tensioner assembly 15. Rotation of the pivot arm 5 causes operation of the belt 8 and then causes operation of the pivot arm 55 in the same direction as the pivot arm 5 in a synchronized or coordinated manner. The rotation of the pivot arm 55 also causes the operation of the belt 8 and then causes the operation of the pivot arm 5 in the same direction as the pivot arm 55 in a synchronous or coordinated manner. Thus, during operation, the pivot arm 5 and the pivot arm 55 operate almost simultaneously by the action of the belt 8.

&Quot; Synchronous " operation can be described as the operation of pivot arm 5 and pivot arm 55, wherein each pivot arm rotates approximately at the same angle approximately at the same time. The " tuned " operation can be described as the operation of pivot arm 5 and pivot arm 55, in which each pivot arm rotates at approximately the same angle, but not at the same angle, in both pivot arms. Rotation of the pivot arms by an unequal angle can be caused, for example, by stretching the belt 8, as described herein (see FIG. 22).

15 is a detailed view of a device in an operating position on the engine. In a conventional Asynchronous Accessory Belt Drive System, the device 1000 of the present invention is configured as shown in Fig. The tensioner 1000 is mounted on the alternator 203 using the fasteners 13 and 133. Belt 200 is routed around crankshaft pulley 201, alternator pulley 202 and tensioner pulley 10 and pulley 101. This arrangement places the belt spans on both sides of the alternator pulley 202. The tension in the belt 200 is maintained by the operation of the tensioner 1000 and the position of the pulley 10 and the pulley 101. [ Belt 200 is typically a multi-ribbed belt known in the art, i. E., Includes a plurality of ribs extending in a longitudinal or an endless direction.

The position of the pivot arm 5 and thus of the pulley 10 is controlled by the belt 8. The position of the pivot arm 55 and thus of the pulley 101 is also controlled by the belt 8. The tension in the belt 8 is controlled by the position of the pulley 10 and the pulley 101. The tension in the belt 8 is maintained by the tensioner assembly 15. The span of the belt 8 engaged with the tensioner assembly 15 is the tension side span of the belt 8. The remaining span 81 of the belt 8 does not require any tension. The tension in the belt 8 forms the torque for the pivot arm 5 and the pivot arm 55 through engagement with the sprocket 52 and the sprocket 552, respectively.

16 is a view showing the orientation and hub load of the pivot arm 5 and the pivot arm 55 at the " rest position ". When the engine auxiliary drive is in the idle state, the tension in the belt 200 is equalized across the belt. The tension of the belt 200 in this state is the initial belt tension, which is set by the tensioner of the present invention. The pivot arm 5 and the pivot arm 55 are connected to each other by a tension on the belt 8 caused by a tensioner assembly 15 supported against the belt 8, ) Side. The tension on the belt 8 causes the pivot arm 5 and the pivot arm 55 to rotate until the torque becomes equal in the opposite direction to the torque formed by the hub load from the belt 200. The hub load of the belt 200 acts on the pivot arm 5 and the pivot arm 55 through the bearing 12 and the central axis of the bearing 102, respectively. This allows torque to be induced in each pivot arm 5 and pivot arm 55 based on the load direction and effective arm length for each arm. Each pivot arm 5 and pivot arm 55 will rotate until the hub load torque is equal to and opposite the belt 8 torque for each pivot arm 5 and pivot arm 55.

The length of the moment arm from the belt 8 acting on the pivot arm 5 is one half (e.g., 26.3 mm) of the pitch diameter of the sprocket 52. The length of the moment arm acting on the pivot arm 5 due to the hub 200 load of the belt 200 is the product of the sine of the arm length and the angle of the force with respect to the pivot arm 5 - referred to as the effective arm length. 17A is a detailed view of pivot arm loading conditions. 17B is a detailed view of the pivot arm load condition.

The length of the moment arm of the belt 8 acting on the pivot arm 55 is one half (e.g., 26.3 mm) of the pitch diameter of the sprocket 552. The length of the moment arm acting on the pivot arm 55 due to the belt 200 hub load is the sine of the angle of the force with respect to the pivot arm 55 of the arm length - referred to as the effective arm length.

In the belt drive, when the torsion angle of the belt around the pulley is 60 degrees, the hub load formed by the tension in the belt is roughly equal to the tension in the belt. For example, if the tension in each belt span is 100 N, the hub load on the pivot arm 5 is 100 N when the twist angle is 60 degrees.

The torque formed on the pivot arm 5 is the product of the hub load 100 N and the effective arm. When the length of the effective arm is 7 mm, the torque for the pivot arm 5 due to the hub load is 100 N x 0.007 m = 0.70 Nm.

The tension in the belt 8 would have to be 0.7 Nm / 0.0263 m = 26.6 N to form a torque in the opposite direction to the pivot arm 5 and the pivot arm 55.

As can be seen in the previous example, the tension on the belt 8 should only be approximately 3/4 of the belt 200 relaxed side tension. This is the ratio of the effective arm length to the sprocket 52 and the radius of the sprocket 552.

18 is a view showing the orientation and hub load of the pivot arm 5 and the pivot arm 55 at the alternator startup mode position. During an ignition event in which the alternator becomes the driver pulley of the system instead of the crankshaft, the upper span C in Fig. 18 becomes the relaxation span and the lower belt span D becomes the tension span. When the alternator supplies a torque of 60 Nm for a start event, the tensile side tension must be increased to a level that can support this power transfer level. During a start event, the lower pivot arm 55 is forced to rotate by the increased tension on the belt 200. The tension in the belt 200 increases to a level sufficient to start the engine rotation, that is, to drive the crankshaft.

In the belt driving section, the ratio of the tensile side tension to the relaxed side side tension around the pulley is known as the tensile ratio. It is essential that the tension ratio is approximately 5 in order to maintain proper belt function in the ABDS drive.

The difference in tension around the alternator pulley, which is required to form a 60 Nm torque, in a starting event requiring 60 Nm of torque to be supplied by the alternator,

Torque = r * DELTA T = r (T2-T1)

, Where T2 = tensile tension

T1 = relaxed side tension

R = pulley radius = 0.030 m,

Solving for? T,

DELTA T = torque / r = 60 / 0.030 = 2000N.

It is known that tensile tension must be maintained to maintain a tension ratio of 5 for proper ABDS system function. therefore,

T2 / T1 = 5 < RTI ID = 0.0 > (2)

[Delta] T = T2-T1 [Equation 3]

Is known.

Solving for T2 in equation (3)

T2 =? T + T? 1.

Substituting into equation (2), solving for Tl,

(? T + Tl) / Tl = 5

? T +? 1 = 5T1

? T = 4T1

DELTA T / 4 = Tl

2000/4 = Tl

Tl = 500N.

Substituting into Equation 2 again,

T2 / T1 = 5

T2 / 500 = 5

T2 = 2500 N.

The high tension in the tension span T2 during the start event (see FIG. 18 (D)) indicates that the hub load acting on the pivot arm 55 is shifted to a position where the arm direction is basically parallel to the direction of the hub load (See Fig. 18). This has the effect of temporarily converting the tensioner assembly 502 into a stationary idler. The amount of rotation of the pivot arm 55 is approximately 65 degrees.

The configuration of the pivot arm 5 and the pivot arm 55 is such that the operation of the pulley 10 and the pulley 101 toward the rotary peristyle belt 200 when the respective pivotal arms are rotated toward the belt 200, Is larger than that in the case of rotating away from the belt (200). This requires that the rotation angle of the relaxation side tensioner assembly 501 is smaller than the rotation angle at which the tension side tensioner assembly 502 is moved to maintain the same belt length. Table 1 shows the amount of rotation of each pivot arm 5 and pivot arm 55 during a start event in which belt elongation does not occur.

condition Belt length Δ angle upper arm 5 Angle lower arm 55 Nominal (no load) 884.2 mm - - Alternator start 884.2 mm 25 ° 65 °

Since the belt 200 is stretched due to the load, the relaxation side pivot arm 5 must compensate for such stretching. Assuming that the belt stretching amount due to the load is 3 mm, the relaxation side tensioner must be further rotated by 30 degrees to reduce this additional belt length. Table 2 shows the amount of rotation of each pivot arm 5 and pivot arm 55 during a start event and includes information that allows for belt stretching.

condition Belt length Δ angle upper arm 5 Angle lower arm 55 Nominal (no load) 884.2 mm - - Alternator start (no extension) 884.2 mm 25 ° 65 ° Alternator start (elongation) 884.2 mm 55 ° 65 °

As can be seen in Table 2, the relaxation side tensioner pivot arm 5 has to be further rotated by 30 degrees to correct the stretching of the belt 200. 22A is a diagram illustrating the position of a pivot arm in an operating state. 22B is a view illustrating the position of the pivot arm in the operating state. 22C is a view illustrating the position of the pivot arm in the operating state. 22D is a view illustrating the position of the pivot arm in the operating state.

In addition, the configuration is such that the effective length of the pivot arm 5 is reduced when the pivot arm rotates toward the belt 200. This reduction in effective arm length allows the device of the present invention to increase the relaxation side tension and thus increase the tension of the entire belt 200 during an event such as alternator start-up. This is achieved because the tension in the belt 8 is controlled through the tensioner assembly 15. The tensioner assembly 15 induces a torque on the pivot arm 5, which must be opposite the hub load of the belt 200 as described above. The 55 degree rotation of the pivot arm 5 on the relaxation side reduces the length of the effective arm from 7 mm to 4.2 mm.

The tensioner assembly 15 controls the torque at the pivot arm 5, since it controls the tension at the belt 8 and thereby the belt 200. The rotation angle of the pivot arm 5 is smaller than the rotation angle of the pivot arm 55 by 10 degrees. This effectively shortens the span of the belt 8 acting on the tensioner assembly 15, thereby causing rotation of the tensioner assembly 15. [ The rotation of the tensioner assembly 15 causes the tension on the belt 8 to increase. As the tension in the belt 8 increases, the torque for the pivot arm 5 and the pivot arm 55 increases. The hub load force which forms the torque opposite to the pivot arm 5 and the pivot arm 55 must be increased to be in equilibrium.

The torque for the pivot arm 5 due to the belt 8 is simply divided by the new effective arm length in order to calculate the tension on the belt 200 that is approximately the same as the hub load as previously suggested. The new tension in the belt 8 is 81 N. The torque for the pivot arm 5 due to the belt 8 is 2.13 Nm. The tensile force in the belt 200 is 2.13 Nm / 0.0042 m = 507 N. This tension exceeds the initially calculated minimum relaxation side tension (T1) and forms an appropriate total belt tension. The ability of the device of the present invention to increase relaxation side tension is advantageous in that it reduces the overall initial tension - beneficial for belt life and accessory life.

Thus, for a 60 Nm startup event, the device of the present invention provides a relaxed side tension of at least 500 N. For a 60 Nm regenerative braking event, the device of the present invention provides a relaxed side tension of at least 500 N. In a no-load situation, the device of the present invention provides a reduced relaxed side tension of 100 N. For intermediate load situations such as 20 Nm alternator load, the device of the present invention provides an essential relaxed side tension of 167 N.

It should be noted that all numerical values used in this description are merely examples used for illustrative purposes and are not intended to limit the scope of the present invention.

Damping belt vibration is also an important function of the tensioner. Damping is achieved primarily by forming a resistance to movement in the tensioner pivot arm. It is generally considered advantageous to have asymmetric damping in the ABDS tensioner. The asymmetric damping is such that the resistance to the operation of the tensioner arm is different depending on the direction of the tensioner pivot arm operation.

19 is a detailed view of the clutch spring. 20 is a detailed view of the clutch spring. The damping in the tensioner of the present invention is achieved by the interaction of the damping assembly 4 with the clutch spring 3 and the pivot arm 3 and between the damping assembly 44 and the clutch spring 33 and the pivot arm 55 . Is the right hand wind of the clutch spring 3, and the clutch spring 33 is the left hand wind. The clutch spring 3 is attached to the base 1 through engagement of the tang 31 into the slot 911. The clutch spring 33 is attached to the base 1 through the engagement of the tang 331 into the slot 910 (see FIG. 21). 21 is a detailed view of the base.

The clutch spring 3 acts as a one-way clutch for the damping assembly 4. The clutch spring 3 limits the damping assembly 4 so that the damping assembly will only rotate freely in the direction in which only the pivot arm 5 rotates toward the belt 200 side. The damping assembly 4 is urged outwardly such that the damping shoe 41 forms an outward pressure against the damping ring 42 and thus the damping ring contacts the damping surface 51 of the pivot arm 5 . The vertical force formed by this outward pressure is combined with the coefficient of friction of the damping ring 42 relative to the pivot arm 5 to form a frictional force that resists motion between the damping assembly 4 and the pivot arm 5. [ Due to the frictional force, the damping assembly 4 forces the pivot arm 5 to rotate each time this damping assembly 4 is rotated.

The clutch spring 33 acts as a one-way clutch for the damping assembly 44. The clutch spring 33 limits the damping assembly 44 so that the damping assembly will rotate freely only in the direction in which the pivot arm 55 rotates toward the belt 200 side. The damping assembly 44 is forced outwardly such that the damping shoe 441 forms an outward pressure against the damping ring 442 and thus the damping ring contacts the damping surface 551 of the pivot arm 55 . The vertical force created by this outward pressure is combined with the coefficient of friction of the damping ring 442 relative to the pivot arm 55 to create a frictional force that resists motion between the damping assembly 44 and the pivot arm 55. Due to the frictional forces, the damping assembly 44 causes the pivot arm 55 to rotate each time the damping assembly 44 rotates.

During vehicle operation in which the tension side span of the belt 200 engages the tensioner assembly 15, the torque applied to the pivot arm 5 by the hub load increases as the tension of the belt 200 increases, 5 rotate in a direction away from the belt 200. During this movement away from the belt 200 the clutch spring 3 is locked against the damping assembly 4 to eliminate the ability of the damping ring 4 to rotate with the pivot arm 5, 5) stops rotating. The pivot arm 5 can then only rotate after the torque caused by the increasing hub rod exceeds the resistance by the damping assembly 4. [ In addition, the tension in the relaxation side span of the belt 200 decreases, and each pivot arm 55 moves toward the belt 200 side. Since the clutch spring 33 releases the clutch in this rotation direction, the pivot arm 55 freely rotates, thereby maintaining the proper relaxation side span belt tension.

During a vehicle operation in which the tension span engages the tensioner assembly 502, the torque applied to the pivot arm 55 by the hub load increases as the tension of the belt 200 increases so that the arm moves away from the belt 200 Direction. During this movement away from the belt 200 the clutch spring 33 is locked against the damping assembly 44 to eliminate the ability of the damping assembly 44 to rotate with the pivot arm 55, 55). The pivot arm 55 can only rotate after the torque caused by the increasing hub load exceeds the resistance by the damping assembly 44. [ In addition, the tension in the relaxed side span of the belt 200 decreases, and each pivot arm 5 moves toward the belt 200 side. Since the clutch spring 3 disengages the pivot arm 5 in this rotation direction, the pivot arm 5 freely rotates and thus maintains the appropriate relaxation side span belt tension on the belt 200. [

The rotational resistance of the pivot arm 5 caused by the damping assembly 4 acting in conjunction with the clutch spring 3 forms a greater resistance to operation in one direction than in the other direction. The different resistance to rotation forms an asymmetric damping in the tensioner assembly 501.

The rotational resistance of the pivot arm 55 caused by the damping assembly 44 acting in conjunction with the clutch spring 33 forms a greater resistance to operation in one direction than in the other direction. This different resistance to rotation forms an asymmetric damping in the tensioner assembly 502.

The BAS system also operates in a normal mode in which the alternator imparts a load to the crankshaft pulley through the belt 200, for example, when the alternator generates power.

The BAS system also operates in a mode in which the alternator applies a high load to the crankshaft pulley, thereby assisting the braking of the vehicle, also known as regenerative braking. In the regenerative braking event, the load of the belt is opposite to the load of the belt described above in the alternator starting event. In this case, the function of the tensioner of the present invention is merely switched so that the tension side span of the belt 200 is supported on the tensioner assembly 501 and the relaxed side span of the belt 200 is supported on the tensioner assembly 502 .

Additional embodiments include, but are not limited to, sprocket 52 and sprocket 552, each of which is individually or in combination, non-circular in shape. Each sprocket 52 and sprocket 552 may be non-coaxial with each of the pivot axes of the pivot arm 5 and the pivot arm 55. Sprocket 52 and sprocket 552 may be eccentric with respect to pivot arm 5 and pivot arm 55 and each may have a different offset. The pivot arm 5 may have a different eccentric offset than the pivot arm 55. The sprocket 52 and the sprocket 552 may have different diameters. The belt 8 need not necessarily have a plurality of teeth to be uniformly spaced apart from one another, i.e. the belt 8 may have an end free of span 81. [ The belt 8 does not necessarily have to be an endless, uniformly spaced apart plurality of teeth, but rather should be tooth-shaped only at the interface with the sprocket 52 and the sprocket 552. The belt 8 may be a flexible endless member such as a flat belt, a flat belt capable of supporting a tensile load, a rope or a cable. The belt 8 may be a rigid bar hinged to the vicinity of the tensioner assembly 15. The belt 8 may be replaced by a compressible member representing the span 81 of the belt 8.

26 is a detailed rear view of the tensioner mounted on the alternator; The fastener (13) and the fastener (133) are used to attach the tensioner (1000) to the alternator (203).

27 is a detailed rear view of the tensioner mounted on the alternator.

28 is a bottom view of the tensioner arm; The end 1541 of the spring 154 engages between the tab 1530 and the tab 1531 on the pivot arm 153.

29 is a perspective view of sections 29-29 in FIG. The damping assembly 4 is frictionally engaged with the surface 51 of the pivot arm 5. The damping assembly 44 is frictionally engaged with the surface 551 of the pivot arm 55. The clutch spring 3 is frictionally engaged with the damping shoe 41. The clutch spring 33 is frictionally engaged with the damping shoe 441. The clutch spring 3 and the clutch spring 33 are respectively subjected to a load in the releasing direction, which means that the respective diameters are expanded when the applied load increases. The expansion of the clutch spring 3 presses the damping shoe 41 against the damping ring 42 and eventually presses against the surface 51 to slow or stop the rotation of the pivot arm 5. The expansion of the clutch spring 33 presses the damping shoe 441 against the damping ring 442 and eventually presses against the surface 551 to slow or stop the rotation of the pivot arm 55.

For example, when the belt 8 moves in the direction M1, the clutch spring 3 will be subjected to a load in the winding direction and thus will not resist rotation of the pivot arm 5. [ However, the clutch spring 33 will be subjected to a load in the unwinding direction, so that the damping assembly 44 will resist rotation of the pivot arm 55.

When the belt 8 moves in the direction M2, the clutch spring 3 will be subjected to a load in the unwinding direction and thus resist the rotation of the pivot arm 5. [ However, the clutch spring 33 will be subjected to a load in the winding direction, so that the damping assembly 44 will not resist rotation of the pivot arm 55.

The tensioner assembly 15 will maintain the load on the belt 8 independent of the direction of movement of the belt 8. [ The tensioner assembly 15 will maintain the load on the belt 200 through the respective pivot arm 5 and pivot arm 55 regardless of the direction of movement of the belt 200.

30 is a perspective view of a modified example. A variant includes an idler assembly 100 and an idler assembly 200 that are pivotably engaged with the base 300, respectively. Tensioner assembly 340 is pivotally mounted to base 300. A regulator 35 is used to adjust the position of the tensioner assembly 340. Each idler assembly 100, 200 pivots evenly about its respective pivot axis. The pivot axis for the idler assembly 100 is a post 3310. The pivot axis for the idler assembly 200 is a post 3315 (see FIG. 47).

31 is a plan view of the embodiment of Fig.

32 is an exploded view of the embodiment of Fig. The adjuster member 35 adjusts the load that causes the tensioner 340 to engage the belt 315. Each retainer 355 holds each idler assembly 100, 200 in its proper position. A damping mechanism 140 is disposed between the idler assembly 100 and the base 300. A damping mechanism 240 is disposed between the idler assembly 200 and the base 300. Torsion springs 320 and 360 are engaged between the respective idler assemblies 100 and 200 and the base 300. Each spring 320, 360 acts as a one-way clutch that engages damping mechanisms 140, 240 and base 300.

A bushing 368 is engaged between each retainer 355 and the assemblies 100, 200. The fasteners 18, 19, 20, 25, 30 attach the cover 375 to the base 300. A bushing 370 is engaged between the base 300 and the respective assembly 100, 200.

The flexible member 315 is not made of an endless length, that is, it has a separate end. Each end of the flexible member 315 is attached to the lower eccentric arms 130, 230, respectively.

33 is a cross-sectional view of the embodiment of Fig. The eccentric idler assembly 100 includes an upper eccentric arm 110, a fastener 115, an idler assembly 12, a dust shield 125, a lower eccentric arm 130, a spring 320 and a damping mechanism 140 . The fastener 115 connects the upper arm 110 to the lower arm 130. The bushing 368 engages the upper arm 110. The bushing 370 engages the lower arm 130.

The idler assembly 120 and the dust shield 125 are coaxial with the eccentric shaft 1320. The damping mechanism 140 is coaxial with the pivot axis 1310. The eccentric shaft 1120 is coaxial with the eccentric shaft 1320. The pivot axis 1110 is coaxial with the pivot axis 1310.

34 is a side view of the eccentric arm cam; The idler assembly includes a lower eccentric arm (130). The arm 130 includes a pivot shaft 1310, an eccentric shaft 1320, a tooth 1340, a cam portion 1350, and a tang 1360. Eccentric shaft 1320 and pivot axis 1310 are not coaxial, but offset by distance 1330 instead. The portion 1370 engages the bearing 121. The radius R1 of the tooth 1340 is smaller than the radius R2 of the cam 1350. [ The belt 315 can progressively engage the cam portion 1350 when the arm 130 pivots.

Figure 35 is a perspective view of the arm of Figure 34; The arm 130 includes a tang 1360. One end of the belt 315 is captured by the tangs 1360. The threaded hole 1380 receives the fastener 115.

Figure 36 is a perspective view of the arm of Figure 37; Lower arm 230 includes tang 2360. The other end of the belt 315 is engaged with the tangs 2360. The portion 2370 engages the bearing 221. The threaded hole 2380 receives the fastener 215.

37 is a side view of the eccentric arm cam. The idler assembly includes a lower eccentric arm (230). The arm 230 includes a pivot shaft 2310, an eccentric shaft 2320, a tooth portion 2340, a cam portion 2350, and a tang 2360. Eccentric shaft 2320 and pivot axis 2310 are not coaxial, but offset by distance 2330 instead. The radius R1 of the tooth portion 2340 is smaller than the radius R2 of the cam portion 2350. [ The belt 315 may progressively engage the cam portion 2350 when the arm 230 pivots.

38 is a side view of the eccentric upper arm. The upper eccentric arm 110 includes a pivot axis 1110 and an eccentric axis 1120. The pivot axis 1110 and the eccentric axis 1120 are not coaxial, but offset by a distance 1130 instead. The portion 1140 is pivotally engaged with the retainer 355 through the bushing 368. [

39 is a perspective view of the arm of Fig. The recess 1150 receives the fastener 115.

40 is a side view of the upper eccentric arm. The upper eccentric arm 210 includes a pivot axis 2110 and an eccentric axis 2120. The pivot axis 2110 and the eccentric axis 2120 are not coaxial, but offset by the distance 2130. [ The portion 2140 is pivotally engaged with the retainer 355 through the bushing 368. [

41 is a perspective view of the arm of Fig. The recess 2150 receives the fastener 215.

Figure 42 is a side cross-sectional view of the embodiment of Figure 31; The eccentric idler assembly 200 includes an upper eccentric cam 210, a fastener 215, an idler assembly 120, a dust shield 225, a lower eccentric arm 230, a damping mechanism 240, . The fastener 215 connects the arm 210 to the arm 230. The upper arm 210 is engaged with the retainer 355 through the bushing 368. [

The idler assembly 220 and the dust shield 225 are coaxial with the eccentric shaft 2320. The damping mechanism 240 is coaxial with the pivot axis 2310. The eccentric shaft 2120 is coaxial with the eccentric shaft 2320. The pivot axis 2110 is coaxial with the pivot axis 2310.

43 is a detailed view of the idler assembly. The idler assembly (120) includes a bearing (121) and an idler (122). The idler assembly 220 includes a bearing 221 and an idler 222. The idler assemblies 120 and 220 are identical in shape and function.

Figure 44 is a detailed view of the damping mechanism for the embodiment of Figure 30; The damping mechanism 140 includes a transmission ring 141, a damping shoe 142, and a damping ring 143. The delivery ring 141 is cylindrical with an inner surface 1410, a slot 1411, a face 1412 and a face 1413 (see FIG. 45). The damping shoe 142 is cylindrical in shape with the gap 1425 extending in the axial direction and the tab 1424 projecting in the axial direction. Tab 1424 includes face 1422 on the opposite side of face 1423. The damping ring 143 is cylindrical in shape with the gap 1430 extending in the axial direction. The damping ring 143 and the damping shoe 142 are coaxial with the transmission ring 141. Face 1413 is on the opposite side of face 1423. Face 1412 is on the opposite side of face 1422.

Face 1410 is frictionally engaged with spring 320. The outer surface 1431 of the damping ring 143 frictionally engages the inner surface 1390 of the lower eccentric arm 130 (see FIG. 35A). The damping shoe 142 acts in a spring-like manner to urge the outer surface 1441 outwardly against the inner surface 1442 and thereby force the surface 1431 outwardly against the surface 1390 . The outward spring force forms a normal force for frictional engagement of the damping mechanism 140 with respect to the arm 142. As the arm 142 rotates toward the belt 200, the spring 320 clutters and releases the damping mechanism 140. The arm 142 freely rotates toward the belt 200 side. As the arm 142 rotates away from the belt furnace 200 the outer surface of the spring 320 extends radially in the unwinding direction thereby clustering the surface 1410 of the damping mechanism 140, Lt; / RTI > The rotation of the arm 142 is resisted by the frictional engagement of the damping mechanism 140 and the arm 142.

The damping mechanism 240 is the same as the damping mechanism 140 in shape and function. Corresponding reference numerals to the damping mechanism 240 are indicated in parentheses in Fig. The delivery ring 241 is a cylindrical shape having an inner surface 2410, a slot 2411, a face 2412 and a face 2413. The damping shoe 242 is a cylindrical shape with the gap extending axially and the tab 2424 projecting axially. The tab 2423 has a face 2422 opposite the face 2423. The damping ring 243 has a cylindrical shape in which the gap extends in the axial direction. The damping mechanism 240 includes a transmission ring 241, a damping shoe 242, and a damping ring 243. The damping ring 234 and the damping shoes 242 are coaxial with the transmission ring 241 and the face 2413 is on the opposite side of the face 2423. Face 2412 is on the opposite side of face 2422.

Face 2410 is frictionally engaged with spring 360. The outer surface 2431 of the damping ring 243 is frictionally engaged with the surface 2390 of the lower eccentric arm 230 (see FIG. 36A). The damping shoe 242 acts in a spring-like manner to urge the outer surface 2441 outwardly against the inner surface 2442 and thereby force the surface 2431 outwardly against the surface 2390 . The outward spring force creates a normal force for frictional engagement of the damping mechanism 240 relative to the arm 242. When the arm 242 rotates toward the belt 200, the spring 360 clutters and releases the damping mechanism 240. The arm 242 freely rotates toward the belt 200 side. As the arm 242 rotates away from the belt furnace 200 the outer surface of the spring 360 extends radially in the unwinding direction thereby clustering the surface 2410 of the damping mechanism 240, Lt; / RTI > The rotation of the arm 242 is resisted by the frictional engagement of the damping mechanism 240 and the arm 242.

45 is a view showing a damping mechanism for the embodiment of FIG. 30. FIG.

Figure 46 is a cross-sectional view of the embodiment of Figure 31; The base assembly 300 includes a retainer 355, a receiver 310, a belt 315, a spring 320, a bushing 370, a base 330, a spring 360, a cover 375, an idler 335, An idler 345, and a tensioner assembly 340. The belt 315 is a toothed belt or a synchronous belt. Belt 315 engages sprocket 1340 and sprocket 2340 of each arm 130, 230, respectively. The belt 315 is attached to the sprocket 1340 by a tang 1360. The belt 315 is attached to the sprocket 2340 by a tang 2360. Each idler 335, 345 has a smooth surface that engages the backside of the belt 315.

The arm 3200 of the spring 320 is located within the pocket 3320. The arm 3600 of the spring 360 is located in the pocket 3325. The tensioner assembly 340 is pivotally attached to the post 3345 by a fastener 20. The cover 375 is attached to the base 300 by the fastener 30 and the fastener 25.

Figure 47 is a detail view of the base of the embodiment of Figure 30; The base 300 includes a cylindrical post 3310, a cylindrical post 3315, a cylindrical post 3330, a cylindrical post 3335, a cylindrical post 3345, a receiver 3340, a pocket 3320 and a pocket 3325 . The pocket 3320 accommodates the arm 3200. The pocket 3325 receives the arm 3600.

The idler 335 is journaled to the post 3330. The idler 345 is journaled to the post 3335. The bushing 325 is coaxial with the post 3310. The bushing 370 is coaxial with the post 3315. The pivot axis 1310 is coaxial with the post 3310. The pivot axis 2310 is coaxial with the post 3315. The regulator 35 is engaged with the receiver 3340.

Figure 48 is a detail view of the spring of the embodiment of Figure 30; The spring 320 includes an arm 3200 at one end. The arm 3200 engages the pocket 3320 and thus the anchoring arm 3200.

Figure 49 is a detail view of the spring of the embodiment of Figure 30; The spring 360 includes an arm 3600 at one end. The arm 3600 engages the pocket 3325, so that the pocket anchors the arm 3600.

Figure 50 is a plan view of the tensioner of the embodiment of Figure 30; The fastener 20 is engaged with the hole 3471.

51 is a side view of the tensioner of Fig.

52 is a side view of the tensioner of Fig. Each pin 3510, 3511 is supported and positioned on the tensioner 340 in the base 300. The pins 3510 and 3511 provide a clearance for the idler 3500.

53 is a cross-sectional view of the tensioner of Fig. The tensioner assembly 340 includes a cover 3410, a pivot pin 3420, a bushing 3430, a torsion spring 3440, a bushing 3450, an arm 3460, a base 3470, a pin 3480, 3490 and an idler 3500. The bushing 3430 and bushing 3450 are coaxial with the arm 3460. The spring 3340 is coaxial with the arm 3460 and is engaged between the arm 3460 and the cover 3410. The pivot pin 3420 is coaxial with the arm 3460 and is fixedly attached to the base 3470. The pivot pin 3480 is coaxial with the bushing 3490 and is fixedly attached to the arm 3460. The idler 3500 is coaxial with the bushing 3490. Tensioner assembly 340 is well known in the automatic belt tensioner industry, which is commonly found in automotive and industrial applications.

54 is an exploded view of the tensioner of Fig. Holes 3471 engage posts 3345.

FIG. 55 is a detailed view of the base of FIG. 47; FIG. The tensioner 340 pivots about the post 3345. The regulator 35 adjusts the position of the tensioner 340 with respect to the belt 315 and thereby adjusts the load imparted to the belt 315.

FIG. 56 is a detailed view of the base of FIG. 47; FIG. The tensioner assembly 340 is installed so that its position is adjustable. The regulator 35 is threadedly engaged with the base 3300. The position of the adjuster 35 determines the position of the tensioner assembly 340. The extension position of the regulator 35 is an initial installation position. Screwing to the regulator 35 causes the tensioner 340 to pivot about the post 3345 and thereby apply a load to the belt 315. [ This moves the device to the retracted position (FIG. 57), which gradually increases the tension on the ABDS belt 200. The tension of the belt 200 is adjusted for proper system performance in this manner.

FIG. 57 is a detailed view of the base of FIG. 47; FIG. The regulator 35 is shown in the "threaded" state-belt 315 and the maximum tension state for the belt 200 (see FIG. 15).

This modification includes the cam 1350 and the cam 2350. Each of cam 1350 and cam 2350 is engaged with belt 315. The angular movement of the lower eccentric arm 130 and the lower eccentric arm 230 is the same as long as the arms of the tensioner assembly 340 are held stationary.

It is desirable to increase the tension on the relaxed side of the belt 200 during certain operating events as described elsewhere herein (see FIG. 15). This is accomplished by deflecting the arm 3460, which deflects the spring 3440, thereby increasing the torque at the arm 3460. [ The torque at arm 3460 is opposite to the tension at belt 315 in the form of a hub load for idler 3500. By deflecting the arm 3460 away from the belt 315, the torque at the arm 3460 is increased. This causes the tension at the belt 315 and thus the tension at the relaxed span of the belt 200 to increase.

The cam 2350 rotates in a direction away from the belt 315 while the lower eccentric arms 130 and 230 rotate in the clockwise direction as shown in Fig. It engages. This increases the take-up of the belt 315, causing the arm 3460 to deflect, which increases the tension on the belt 315. This increases the tension in the belt (200). Conversely, when the lower eccentric arm 130, 230 rotates counterclockwise as shown in FIG. 56, while the cam 2350 rotates in a direction away from the belt 315, 315). This increases the take-up of the belt 315, causing the arm 3460 to deflect, which increases the tension on the belt 315. This increases the tension at the relaxed side span of the belt 200. [

In operation, each cam profile 1350, 2350 enables an additional take-up of the belt 315. The additional take-up of the belt 315 has two advantages. The additional take-up increases the deflection of the tensioner 340, which increases the movement of the relaxed side arm (idler 100) attached to the end of the belt 315. The increased deflection of the tensioner 340 provides an additional level of tension control to the entire device. The shape of the cam profile can dramatically change the relaxation side tension of the belt 200, that is, the radius R2 can be changed. The increased movement of the relaxation side tensioner arm causes the arm to move to the belt side at a higher speed by the cam than in the absence of the cam in the situation where the load of the auxiliary belt 200 is increased. This increases the relaxation side tension of the belt 200 at an increased speed. This provides the ability to further adjust the tensioner to the desired application.

A variant adds transmission rings 141, 241 to each damping mechanism 140, 240. The transmission rings 141 and 241 absorb pressure from the respective clutch springs 320 and 360 and separate the respective clutch springs from the respective damping shoes 142 and 242. Each damping shoe is rotatably secured to a respective transmission ring 141, 241 to enable clutching and to control the normal force on the damping ring by the damping shoe.

Tensioner assembly 340 is a miniature Z-style tensioner known in the art. The tensioner occupies an unused space in the plane of the belt 200 if not otherwise. The tensioner 340 is mounted so that its position is adjustable. The position of the fastener (35) determines the position of the tensioner assembly (240). This makes it possible to control the installation tension on the belt 200 by simply adjusting the fastener 35. By moving the tensioner assembly 340 to the side of the belt 315, the belt tension is increased, and thus the tension of the auxiliary belt 200 is increased.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it will be apparent to one skilled in the art that changes may be made in the arrangement, relationship and method of the components without departing from the spirit and scope of the invention as set forth herein.

Claims (8)

As a tensioner,
Base;
A first pivot arm pivotably engaged with the base for eccentric movement about a first axis and having a first pulley journalled;
A second pivot arm pivotably engaged with the base for eccentric movement about a second axis and to which the second pulley is journaled;
A flexible tension member engaged with the first pivot arm and the second pivot arm;
A tensioner assembly pivotably engaged with the base and engaged with the flexible tension member;
A first damping assembly for frictionally engaging the first pivot arm and applying a greater damping force to the first pivot arm in a first direction than in the second direction; And
A second damping assembly that frictionally engages the second pivot arm and applies a greater damping force to the second pivot arm in a first direction than in the second direction,
Wherein the first pivot arm includes a first cam portion that progressively engages the flexible tension member such that the first pivot arm torque can be varied. 2. The tensioner of claim 1, wherein the second pivot arm includes a second cam portion that progressively engages the flexible tension member such that the second pivot arm torque can be varied. The tensioner assembly of claim 1, wherein the tensioner assembly
Tensioner pivot arm;
A tensioner pulley journaled to the tensioner pivot arm; And
Tensioner torsion spring that engages between tensioner pivot arm and base
Wherein the tensioner pivot arm applies a load to the flexible tension member via a tensioner pulley. 4. The tensioner according to claim 3, wherein the position of the tensioner is adjusted by the adjusting member with respect to the flexible tension member. 4. The tensioner of claim 3, further comprising an idler journaled to the tensioner pivot arm and engageable with the flexible tension member. The tensioner according to claim 1, wherein the flexible tension member comprises a toothed belt. 2. The tensioner of claim 1, wherein the tensioner is mounted to an alternator. The tensioner according to claim 1, wherein the flexible tension member is not endless.

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