CRANKSHAFT BALANCER ARRANGEMENT AND A DRIVETRAIN

Abstract

Crankshaft balancing arrangement (14), comprising: a crankshaft (18) rotatable about a longitudinal axis; a drive element (26A) fixed to the crankshaft; a first shaft (28) rotatable about a first axis of rotation, wherein the first shaft is rotatable in response to rotation of the crankshaft; a weight member (42A) extending from the first shaft, the weight member positioned along the first shaft to balance the crankshaft during rotation of the crankshaft and the first shaft; a first drive element (26B) and a second drive element (48), wherein the first shaft and a portion (44A) of the weight element (42A) are each part of the first drive element (26B) and the second drive element (48); and wherein the first and second drive elements of the first shaft each define a cavity (52) opposite the portion of the weight element, wherein the first shaft (28) has a first end and a second end spaced apart along the first axis of rotation, and the first shaft (28) defines a length (40A) between the first and second ends of the first shaft; the first shaft is arranged along a plane (58A, 58B) and the plane (58A, 58B) contains the first axis of rotation axially with respect to the length of the first shaft to divide the first shaft (28) into two halves to define a first region and a second region; and wherein a major portion of the cavity (52) is disposed in the first region and a major portion of the portion (44A) of the weight element (42A) is disposed in the second region, wherein the cavity (52) is further defined as a plurality of cavities spaced apart from one another, each of the cavities being opposite the portion (44A) of the weight member (42A), wherein the cavities (52) are elongated.

Description

INTRODUCTION

[0001] A powertrain may include a crankshaft that rotates about an axis in response to combustion in cylinders, which moves the pistons. The rotation of the crankshaft may be discontinuous, meaning it is not a continuously smooth revolution. Therefore, some powertrains use a counterbalance device to minimize the discontinuous rotation of the crankshaft. SUMMARY

[0002] The invention is defined by the independent claims.

[0003] The present disclosure provides a crankshaft balancer assembly having a crankshaft rotatable about a longitudinal axis. The crankshaft balancer assembly includes a drive member attached to the crankshaft. The crankshaft balancer assembly also includes a first shaft rotatable about a first axis of rotation. The first shaft is rotatable in response to rotation of the crankshaft. The crankshaft balancer assembly includes a weight member extending from the first shaft. The weight member is positioned along the first shaft to balance the crankshaft during rotation of the crankshaft and the first shaft. The crankshaft balancer assembly also includes a drive member surrounding the first shaft and a portion of the weight member. The first shaft drive member defines a cavity opposite the portion of the weight member.

[0004] The present disclosure also provides a powertrain having a housing and a crankshaft balancer assembly at least partially disposed within the housing. The crankshaft balancer assembly includes a crankshaft rotatable about a longitudinal axis. The crankshaft balancer assembly includes a drive member attached to the crankshaft. The crankshaft balancer assembly also includes a first shaft rotatable about a first axis of rotation. The first shaft is rotatable in response to rotation of the crankshaft. The crankshaft balancer assembly includes a weight member extending from the first shaft. The weight member is positioned along the first shaft to balance the crankshaft during rotation of the crankshaft and the first shaft. The crankshaft balancer assembly also includes a drive member surrounding the first shaft and a portion of the weight member.The drive element of the first shaft defines a cavity opposite the portion of the weight element.

[0005] The detailed description and drawings support and describe the disclosure, but the scope of the disclosure is defined solely by the claims. While some of the best modes and other embodiments for carrying out the claims have been described in detail, alternative designs and embodiments for practicing the disclosure defined in the appended claims are possible.

[0006] DE 10 2007 006 697 A1 describes a torque balancing device for an internal combustion engine, consisting of a first and a second counter-rotating balance shaft arranged in a housing. The first and second shafts have a first and a second imbalance, respectively. The imbalance is defined by a cavity in each case.

[0007] DE 40 10 856 A1 describes a bearing arrangement for balancing weights to compensate for second-order inertial forces or mass moments. The balancing weight and the bearing arrangement form a structural unit, ensuring the correct angular alignment of the crankshaft and balancing weight.

[0008] DE 10 2010 032 530 A1 describes a balance shaft, in particular for an internal combustion engine, with at least one balance weight detachably attached to the balance shaft and a drive wheel detachably attached to the balance shaft for transmitting a drive torque.

[0009] US Pat. No. 1,658,979 A describes a balancing arrangement for an internal combustion engine. This arrangement comprises two balance shafts. The balance shafts each comprise a gearwheel with openings for introducing an imbalance.

[0010] DE 10 2008 057 947 A1 relates to a balance shaft with a gear for a reciprocating piston engine, with a bearing point, a gear section and an unbalance section. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic perspective view of a powertrain having a crankshaft balancer assembly including a crankshaft, a first shaft, and a second shaft. Fig. 2 is a schematic perspective view of the crankshaft, another configuration of the first shaft, and another configuration of the second shaft. Fig. 3 is a schematic side view of either the first and second shafts. Fig. 4 is a schematic end view of either the first and second shafts illustrating one side of a drive train in one configuration. Fig. Figure 5 is a schematic end view of the shaft of Fig. 4 from another side of the drive element of Fig. 4. Fig. 6 is a schematic end view of either the first and second shafts illustrating a drive member of a different configuration. Fig. 7 is a schematic end view of either the first and second shafts illustrating a drive member of yet another configuration. Fig. Figure 8 is a schematic end view of either the first and second shafts illustrating a drive member of a different configuration. DETAILED DESCRIPTION

[0011] Those skilled in the art will recognize that all directional terms (e.g., above, below, upward, up, down, down, left, right, vertical, horizontal, etc.) are used descriptively of the figures to aid the reader's understanding and do not represent limitations (e.g., on position, orientation, or use, etc.) on the scope of the disclosure, which is defined by the appended claims. Furthermore, the term "substantially" may refer to minor blurring or slight deviations from a state, quantity, value, or measure, etc., some of which are within the variations or tolerances of the manufacturing process.

[0012] Regarding figures in which the same numbers designate the same or corresponding parts across different views, it is generally Fig. 1 shows a drive train 10.

[0013] The powertrain 10 may be used in a vehicle application or a non-vehicle application. The vehicle that may utilize the powertrain 10 may include a motor vehicle, such as a car, a truck, etc. However, it should be appreciated that the vehicle may alternatively be a non-motor vehicle, such as an agricultural vehicle, a marine vehicle, an aircraft, etc. Furthermore, the powertrain 10 may be used with a hybrid vehicle, an autonomous vehicle, or any other suitable application.

[0014] The powertrain 10 may include a housing 12. Furthermore, the powertrain 10 may include a crankshaft balancer assembly 14 disposed at least partially within the housing 12. The housing 12 may be of any configuration and may be formed from a plurality of parts that cooperate with one another. Generally, the crankshaft balancer assembly 14 is designed to reduce mass, inertia, and package size while maintaining the balancing forces discussed below.

[0015] The powertrain 10 may include various components, some of which include, but are not limited to, an engine, a transmission, and an axle drive, which are coupled together to rotate the vehicle's wheels to propel the vehicle. The engine may include one or more pistons 16, an output member or crankshaft 18, one or more valves, one or more piston rods 20, etc. The pistons 16 may be coupled to the crankshaft 18 via the piston rods 20.

[0016] The crankshaft 18 may be coupled to an input member of the transmission. The transmission may include a gear assembly and one or more clutches through which torque is transferred from the engine's crankshaft 18 to the input member of the transmission, then to the final drive, and to the wheels to move the vehicle. The wheels may be the front and / or rear wheels of the vehicle. The front and / or rear wheels may be driven by the driveline 10.

[0017] In certain embodiments, the housing 12 may be an engine block defining one or more cylinders 22, each having a combustion chamber, and the pistons 16 are displaceable within the respective cylinders 22 in response to combustion in the respective combustion chamber. Thus, as the respective pistons 16 move, the movement causes the crankshaft 18 to rotate.

[0018] Regarding the Fig. 1 and Fig. 2, the crankshaft balancer assembly 14 includes the crankshaft 18. The crankshaft 18 is rotatable about a longitudinal axis 24. During combustion in the respective combustion chamber, the respective pistons 16 move, causing the crankshaft 18 to rotate about the longitudinal axis 24. The rotation of the crankshaft 18 about the longitudinal axis 24 may be irregular due to the timing of combustion and / or the movement of the pistons 16. In other words, the rotation of the crankshaft 18 about the longitudinal axis 24 may be discontinuous, i.e., not a continuous, smooth revolution, due to the timing of combustion and / or the movement of the pistons 16. Therefore, the crankshaft balancer assembly 14 described herein is configured to minimize the irregular or discontinuous rotation of the crankshaft 18.

[0019] The crankshaft 18 may be disposed at least partially within the housing 12. In certain embodiments, the crankshaft 18 is disposed partially within the housing 12 and partially outside the housing 12. In other embodiments, the crankshaft 18 is disposed entirely within the housing 12. It should be noted that the crankshaft 18 may occupy any location relative to the other various components.

[0020] With further reference to the Fig. 1 and Fig. 2, the crankshaft balancer assembly 14 includes a drive member 26A attached to the crankshaft 18. In certain embodiments, the drive member 26A of the crankshaft 18 may surround the crankshaft 18. The drive member 26A of the crankshaft 18 is attached to the crankshaft 18 such that the crankshaft 18 and the drive member 26A of the crankshaft 18 rotate together. The drive member 26A of the crankshaft 18 may be attached directly or indirectly to the crankshaft 18, and non-limiting examples of attachment types may include fasteners, welding, casting, etc. In certain embodiments, the drive member 26A of the crankshaft 18 is further defined as a gear. When the drive member 26A surrounds the crankshaft 18, the teeth of the gear (of the drive member 26A) may face outward from the longitudinal axis 24.

[0021] The crankshaft balancer assembly 14 also includes a first shaft 28 rotatable about a first rotational axis 30. The first shaft 28 is rotatable in response to the rotation of the crankshaft 18. Depending on the position of the first shaft 28, the rotation of the first shaft 28 may occur directly or indirectly in response to the rotation of the crankshaft 18, which will be discussed in more detail below.

[0022] With reference to the Fig. 1-3, in certain embodiments, the crankshaft balancer assembly 14 may also include a second shaft 32 rotatable about a second rotational axis 34. The second shaft 32 is rotatable in response to the rotation of the crankshaft 18. Depending on the location of the second shaft 32, the rotation of the second shaft 32 may occur directly or indirectly in response to the rotation of the crankshaft 18, which will be discussed in more detail below.

[0023] Fig. 3 is representative of an example that either the first and second shafts 28, 32 or both the first and second shafts 28, 32 can be configured. Therefore, Fig. 3 is used to explain the common features of the first and second waves 28, 32. As in Fig. 3, the first shaft 28 may include a first end 36A and a second end 38A spaced apart along the first rotational axis 30, and the first shaft 28 defines a length 40A between the first and second ends 36A, 38A of the first shaft 28. Similarly, the second shaft 32 may include a first end 36B and a second end 38B spaced apart along the second rotational axis 34, and the second shaft 32 defines a length 40B between the first and second ends 36B, 38B of the second shaft 32.

[0024] The first and second shafts 28, 32 may have different configurations, and the FIGS. illustrate different configurations for the first and second shafts 28, 32. It should be noted that the first and second shafts 28, 32 may have different configurations than those shown.

[0025] Back to the first wave 28 and the Fig. 1 and Fig. 2, the first shaft 28 can be arranged at least partially within the housing 12. In certain embodiments, the first shaft 28 is arranged entirely within the housing 12. Generally, the longitudinal axis 24 and the first rotational axis 30 can be arranged spaced apart from each other and substantially parallel to each other. Thus, the first shaft 28 and the crankshaft 18 can be arranged offset and substantially parallel to each other.

[0026] With reference to the Fig. 1-3, the crankshaft balancer assembly 14 includes a weight member 42A extending from the first shaft 28. The weight member 42A of the first shaft 28 is attached to the first shaft 28 such that the weight member 42A and the first shaft 28 rotate together. The weight member 42A of the first shaft 28 may be attached directly or indirectly to the first shaft 28, and non-limiting examples of the attachment method may include fasteners, welding, casting, etc.

[0027] The weight member 42A of the first shaft 28 can be positioned along the first shaft 28 to balance the crankshaft 18 during rotation of the crankshaft 18 and the first shaft 28. Therefore, as the first shaft 28 rotates, the weight member 42A of the first shaft 28 rotates to counteract the forces of the irregular rotation of the crankshaft 18, ultimately minimizing the irregularities in the rotation of the crankshaft 18. Thus, the weight member 42A of the first shaft 28 is configured to generate forces that balance the rotation of the crankshaft 18. Simply stated, the weight member 42A can minimize the vibrations of the crankshaft 18 during rotation of the crankshaft 18. The weight member 42A of the first shaft 28 can be of any configuration, and the FIGS. are for illustrative purposes only.

[0028] Continuing with the Fig. 1-3, the crankshaft balancer assembly 14 also includes a drive member 26B surrounding the first shaft 28. In certain embodiments, the drive member 26B of the first shaft 28 surrounds the first shaft 28 and a portion 44A of the weight member 42A of the first shaft 28. Therefore, as shown in Fig. 3, a further portion 46A of the weight member 42A of the first shaft 28 is axially spaced from the drive member 26B relative to the length 40A of the first shaft 28. Simply stated, a portion of the weight member 42A of the first shaft 28 does not overlap the drive member 26B relative to the length 40A of the first shaft 28.

[0029] The drive member 26B of the first shaft 28 is attached to the first shaft 28 such that the first shaft 28 and the drive member 26B of the first shaft 28 rotate together. The drive member 26B of the first shaft 28 may be attached directly or indirectly to the first shaft 28, and non-limiting examples of attachment types may include fasteners, welding, casting, etc. In certain embodiments, the drive member 26B of the first shaft 28 is further defined as a gear. The teeth of the gear (the drive member 26B) of the first shaft 28 may be directed outward from the first rotation axis 30.

[0030] Back to the second wave 32 and the Fig. 1 and Fig. 2, the second shaft 32 can be at least partially disposed within the housing 12. In certain embodiments, the second shaft 32 is disposed entirely within the housing 12. Generally, the longitudinal axis 24 and the second rotational axis 34 can be arranged spaced apart from each other and substantially parallel to each other. Thus, the second shaft 32 and the crankshaft 18 can be offset and substantially parallel to each other. Furthermore, in certain embodiments, the longitudinal axis 24, the first rotational axis 30, and the second rotational axis 34 can be spaced apart from each other and substantially parallel to each other. Therefore, the crankshaft 18, the first shaft 28, and the second shaft 32 can be offset and substantially parallel to each other.

[0031] Furthermore, the crankshaft balancer assembly 14 may include a weight member 42B extending from the second shaft 32. Thus, the weight member 42B of the second shaft 32 is attached to the second shaft 32 such that the weight member 42B and the second shaft 32 rotate together. The weight member 42B of the second shaft 32 may be attached directly or indirectly to the second shaft 32, and non-limiting examples of the attachment method may include fasteners, welding, casting, etc.

[0032] The weight element 42B of the second shaft 32 can be positioned along the second shaft 32 to balance the crankshaft 18 during rotation of the crankshaft 18 and the second shaft 32. Therefore, as the second shaft 32 rotates, the weight element 42B of the second shaft 32 rotates to counteract the forces of the irregular rotation of the crankshaft 18, ultimately minimizing the irregularities in the rotation of the crankshaft 18. Thus, the weight element 42B of the second shaft 32 is configured to generate forces that balance the rotation of the crankshaft 18. Simply put, the weight element 42B can minimize the vibrations of the crankshaft 18 during rotation of the crankshaft 18. In addition, when using the first and second shafts 28, 32, the weight member 42A, 42B of the first and second shafts 28, 32 may cooperate to balance the crankshaft 18 during rotation of the crankshaft 18.Thus, the weight elements 42A, 42B can minimize the vibrations of the crankshaft 18 during rotation of the crankshaft 18. The weight element 42B of the second shaft 32 can be of any configuration, and the figures are for illustrative purposes only.

[0033] With further reference to the Fig. 1-3, the crankshaft balancer assembly 14 may also include a drive member 26C surrounding the second shaft 32. In certain embodiments, the drive member 26C of the second shaft 32 surrounds the second shaft 32 and a portion 44B of the weight member 42B of the second shaft 32. Therefore, as shown in Fig. 3, another portion 46B of the weight member 42B of the second shaft 32 is axially spaced from the drive member 26C relative to the length 40B of the second shaft 32. Simply stated, a portion of the weight member 42B of the second shaft 32 does not overlap the drive member 26C relative to the length 40B of the second shaft 32.

[0034] The drive member 26C of the second shaft 32 is attached to the second shaft 32 such that the second shaft 32 and the drive member 26C of the second shaft 32 rotate together. The drive member 26C of the second shaft 32 may be attached directly or indirectly to the second shaft 32, and non-limiting examples of attachment types may include fasteners, welding, casting, etc. In certain embodiments, the drive member 26C of the second shaft 32 is further defined as a gear. The teeth of the gear (the drive member 26C) of the second shaft 32 may be directed outward from the second rotation axis 34.

[0035] The position of the first and second shafts 28, 32 relative to the crankshaft 18 can be changed, and non-limiting examples are listed below. As mentioned above, depending on the position of the first and second shafts 28, 32, the shafts 28, 32 can be directly or indirectly rotatable in response to the rotation of the crankshaft 18. Simply put, the position of the first and second shafts 28, 32 relative to the crankshaft 18 can be interchanged.

[0036] With reference to Fig. 1, in certain embodiments, the drive member 26A of the crankshaft 18 and the drive member 26B of the first shaft 28 may mesh such that the rotation of the first shaft 28 is driven by the rotation of the crankshaft 18. Thus, the rotation of the first shaft 28 may be directly driven by the rotation of the crankshaft 18. Furthermore, in this embodiment, the second shaft 32 is spaced from the crankshaft 18, and the rotation of the second shaft 32 may be directly driven by the rotation of the first shaft 28. Thus, the drive member 26B of the first shaft 28 and the drive member 26C of the second shaft 32 may mesh such that the rotation of the second shaft 32 is driven by the rotation of the first shaft 28.Therefore, in this embodiment, the second shaft 32 may be rotatable about the second axis of rotation 34 in response to the rotation of the first shaft 28, such that the rotation of the second shaft 32 is driven by the rotation of the first shaft 28. Additionally, in this embodiment, the first shaft 28 may rotate about the first axis of rotation 30 in the opposite direction from the rotation of the crankshaft 18 about the longitudinal axis 24. Thus, in this embodiment, the second shaft 32 may rotate about the second axis of rotation 34 in the same direction as the rotation of the crankshaft 18 about the longitudinal axis 24. Therefore, in this embodiment, the first and second shafts 28, 32 rotate in opposite directions. As mentioned above, the first and second shafts 28, 32 may be interchangeable, and therefore, in other embodiments, the second shaft 32 may be placed where the first shaft 28 is in . Fig. 1, and the first shaft 28 where the second shaft 32 in Fig. 1 is shown.

[0037] Alternatively, as in Fig. 2, the drive member 26B of the first shaft 28 may be spaced from the drive member 26A of the crankshaft 18 such that the first shaft 28 is not directly driven by the crankshaft 18. In other words, the first shaft 28 is indirectly driven by the crankshaft 18 through the second shaft 32. In this embodiment, the drive member 26A of the crankshaft 18 and the drive member 26C of the second shaft 32 may mesh with each other such that the rotation of the second shaft 32 is driven by the rotation of the crankshaft 18. Furthermore, in this embodiment, the drive member 26B of the first shaft 28 and the drive member 26C of the second shaft 32 may mesh with each other such that the rotation of the first shaft 28 is driven by the rotation of the second shaft 32. Thus, the rotation of the second shaft 32 can be driven directly by the rotation of the crankshaft 18 and the rotation of the first shaft 28 can be driven directly by the rotation of the second shaft 32.In this embodiment, the second shaft 32 may be rotatable about the second axis of rotation 34 in response to the rotation of the crankshaft 18. Thus, the rotation of the second shaft 32 may be driven by the rotation of the crankshaft 18. In this embodiment, the second shaft 32 may rotate about the second axis of rotation 34 opposite to the rotation of the crankshaft 18 about the longitudinal axis 24. Furthermore, in this embodiment, the first shaft 28 may rotate about the first axis of rotation 30 in the same direction as the crankshaft 18 about the longitudinal axis 24. Therefore, in this embodiment, the first and second shafts 28, 32 rotate in opposite directions. As mentioned above, the first and second shafts 28, 32 may be interchanged, and therefore, in other embodiments, the second shaft 32 may be placed where the first shaft 28 is in . Fig. 2, and the first shaft 28 where the second shaft 32 in Fig. 2 is shown.

[0038] With reference to the Fig. 1 and Fig. 2, for example, the crankshaft balancer assembly 14 may optionally include a secondary drive member 48 extending from one or both of the first and second shafts 28, 32. In other words, a secondary drive member 48 may be attached to the first shaft 28 and / or a secondary drive member 48 may be attached to the second shaft 32. In certain embodiments, the secondary drive member 48 may surround the respective shafts 28, 32. Fig. 1 illustrates a secondary drive element 48 in phantom, however, it should be noted that this secondary drive element 48 is optional and thus may be omitted. The secondary drive element 48 may be attached directly or indirectly to one of the first and second shafts 28, 32, and non-limiting examples of the attachment method may include fasteners, welding, casting, etc. In certain embodiments, the secondary drive element 48 is additionally defined as a gear. The gearing of the gear (of the secondary drive element 48) may be directed outwardly from the respective first and second rotational axes 30, 34.

[0039] The secondary drive element 48 in Fig. 1 may engage with an accessory device 50. The accessory device 50 may be any suitable configuration, and non-limiting examples may include a pump, such as an oil pump, a motor, etc. The accessory device 50 may include a drive element 26D (shown in phantom lines in Fig. 1) which is connected to the secondary drive element 48 (also shown in phantom lines in Fig. 1) meshes with each other. In certain embodiments, the drive element 26D of the auxiliary device 50 is additionally defined as a gear. The teeth of the gear (of the drive element 26D) can be directed outward toward the teeth of the gear of the secondary drive element 48, so that the teeth can mesh with each other.

[0040] With reference to Fig. 2, the secondary drive element 48 is arranged differently. In this FIG., the secondary drive element 48 engages either with the drive element 26B of the first shaft 28 or with the drive element 26C of the second shaft 32. Thus, for example, the drive element 26B and the secondary drive element 48 can be attached to the first shaft 28, or the drive element 26C and the secondary drive element 48 can be attached to the second shaft 32. As a further example, with reference to Fig. 2, another secondary drive element 48 may be attached to one of the first and second shafts 28, 32 to mesh with the accessory device 50. Therefore, more than one secondary drive element 48 may be attached to one or both of the first and second shafts 28, 32. Thus, any suitable number of secondary drive elements 48 may be used.

[0041] With reference to the Fig. 1, 2, and 4-8, the drive member 26B, 26C of the first and second shafts 28, 32, as well as the secondary drive member 48, may represent various configurations, some of which are illustrated. The drive member 26B, 26C of the first and / or second shafts 28, 32, as well as the secondary drive member 48, may represent any of the configurations illustrated in the FIGS. It should be noted that the drive member 26B, 26C of the first and second shafts 28, 32, as well as the secondary drive member 48, may have configurations other than those illustrated. The following discusses some examples of the drive member 26B, 26C of the first and second shafts 28, 32, which also illustrate some examples of the secondary drive member 48.

[0042] With continued reference to the Fig. 1, 2 and 4-8, the drive member 26B of the first shaft 28 defines a cavity 52 that is opposite the portion 44A of the weight member 42A of the first shaft 28. Furthermore, the drive member 26C of the second shaft 32 may define a cavity 52 that is opposite the portion 44B of the weight member 42B of the second shaft 32. In addition, the secondary drive member 48 may define a cavity 52 (see Fig. 2); and the subsequent discussion of the different configuration of the cavities 52 refers to the secondary drive element 48.

[0043] Simply put, one or more of the drive members 26A, 26B and the secondary drive member 48 may define one or more cavities 52. Some material of the drive member 26B, 26C and / or the secondary drive member 48 is removed, thereby reducing the mass of the drive member 26B, 26C and / or the secondary drive member 48. By reducing the mass of the drive member 26B, 26C and / or the secondary drive member 48, the inertia when rotating the respective shafts 28, 32 is reduced. Additionally, by reducing the inertia, the noise level of the intermeshing drive members 26A, 26B, 26C, 48 during rotation may be reduced.

[0044] Generally, the cavity 52 is spaced from the respective first and second rotational axes 30, 34. Thus, the cavity 52 is not congruent with the respective first and second rotational axes 30, 34. In certain embodiments, the cavity 52 is spaced radially from the respective first and second rotational axes 30, 34.

[0045] With reference to the Fig. 4 and Fig. 5, in certain embodiments, the cavity 52 may be partially defined by the drive member 26B of the first shaft 28 such that the drive member 26B has a side wall 54 and a base wall 56 defining the cavity 52. Similarly for the second shaft 32 (again see Fig. 4-5), the cavity 52 may be partially defined by the drive member 26C of the second shaft 32 such that the drive member 26C has a side wall 54 and a base wall 56 defining the cavity 52. Therefore, in certain embodiments, the cavity 52 is a recess that does not form a through-bore. In other words, the cavity 52 is a blind hole.

[0046] With reference to the Fig. 1, 2 and 6-8, the cavity 52 may in other embodiments be completely replaced by the drive element 26B of the first shaft 28. Similar to the second shaft 32 (again see Fig. 1, 2, and 6-8), the cavity 52 may be completely replaced by the drive element 26C of the second shaft 32. Therefore, in certain embodiments, the cavity 52 is a through-bore.

[0047] Any number of cavities 52 may be used for the drive element 26B, 26C of the first and / or second shafts 28, 32. Each of the cavities 52 may be opposite the portion 44A, 44B of the weight element 42A, 42B. Therefore, in certain embodiments, one cavity 52 is used for the first and / or second shafts 28, 32 (see Fig. 6). In other embodiments, the cavity 52 may be further defined as a plurality of cavities 52 spaced apart from one another (see Fig. 1, Fig. 2, Fig. 7 and Fig. 8). Moreover, in certain embodiments, the cavity 52 is further defined as a pair of cavities 52 (as best shown in Fig. 7), which are arranged spaced apart from each other, and the cavities 52 are a mirror image of each other. In this embodiment, the pair of cavities 52 may be opposite the portion 44A, 44B of the weight member 42A, 42B. The cavities 52 may be any suitable configuration, and non-limiting examples may be circular, oval, square, triangular, oblong, etc.; and each of the cavities 52 may be the same configuration, or one or more of the cavities 52 may be different configurations from each other. Furthermore, the cavities 52 may be formed by any suitable methods, and non-limiting examples may be casting, machining, etc.

[0048] The above statements for the cavity 52 are applicable to the cavities 52. Therefore, the cavities 52 can be completely defined by the drive element 26B of the first shaft 28, and the cavities 52 can be completely defined by the drive element 26C of the second shaft 32. Furthermore, the cavities 52 can be partially defined by the drive element 26B of the first shaft 28, and the cavities 52 can be partially defined by the drive element 26C of the second shaft 32.

[0049] For example, Fig. 4 a cavity 52 partially through one side of the drive element 26B, 26C and Fig. 5 illustrates a cavity 52 partially defined by another side of the drive member 26B, 26C. In certain embodiments, the drive member 26B, 26C may define a cavity 52 partially defined by one side of the drive member 26B, 26C. In other embodiments, both sides of the drive member 26B, 26C may define a cavity 52. Moreover, in further embodiments, a plurality of cavities 52 may be partially defined by one side or both sides of the drive member 26B, 26C.

[0050] As mentioned above, the Fig. 4-8 are representative of the first and second shafts 28, 32, and representative of the drive element 26B, 26C of the first and second shafts 28, 32. As such, the Fig. 4-8 are applicable to both the first and second shafts 28, 32. As mentioned above, the cavities 52 are opposite the section 44A, 44B of the weight element 42A, 42B of the respective first and second shafts 28, 32. The following discussion describes various examples of the orientation of the cavities 52 with respect to the section 44A, 44B of the weight element 42A, 42B that is surrounded by the drive element 26B, 26C of the respective first and second shafts 28, 32. By having the cavities 52 opposite the section 44A, 44B of the weight element 42A, 42B that is surrounded by the drive element 26B, 26C, the mass of the drive element 26B, 26C can be reduced without changing the balancing forces. Furthermore, this configuration allows the length 40A, 40B of the first and / or second shafts 28, 32 to be reduced compared to a design that does not utilize the cavities 52, which in turn reduces the installation space.

[0051] With reference to the Fig. 4-8, the first shaft 28 can be arranged along a plane 58A, and thus the second shaft 32 can also be arranged along a plane 58B. In certain embodiments, the plane 58A of the first shaft 28 can be congruent with the first axis of rotation 30, and the plane 58B of the second shaft 32 can be congruent with the second axis of rotation 34. Furthermore, in certain embodiments, the planes 58A, 58B of the first and second shafts 28, 32 are congruent.

[0052] Therefore, in certain embodiments, the plane 58A may be axially coincident with the first axis of rotation 30 with respect to the length 40A of the first shaft 28 to split the first shaft 28 in half to define a first portion 60A and a second portion 62A. Furthermore, in certain embodiments, the plane 58B of the second shaft 32 may be axially coincident with the first axis of rotation 30 with respect to the length 40B of the second shaft 32 to split the second shaft 32 in half to define a first portion 60B and a second portion 62B. In various embodiments, the second shaft 32 may be disposed along the plane 58A of the first shaft 28, and the plane 58A of the first shaft 28 may be coincident with the second axis of rotation 34 to split the second shaft 32 in half to define the first region 60B and the second region 62B.

[0053] How best to Fig. 4-8, generally, a majority of the cavities 52 of the first shaft 28 may be disposed in the first region 60A of the first shaft 28, and a majority of the portion 44A of the weight member 42A of the first shaft 28 may be disposed in the second region 62A of the first shaft 28. Furthermore, a majority of the cavity 52 of the second shaft 32 may be disposed in the first region 60B of the second shaft 32, and a majority of the portion 44B of the weight member 42B of the second shaft 32 may be disposed in the second region 62B of the second shaft 32.

[0054] The majority of the cavity 52 may be further defined as the plurality of cavities 52. Thus, the majority of the cavities 52 may be seventy-five percent or more in the first region 60A, 60B. Thus, for example, seventy-five percent or more of the cavities 52 are located in the first region 60A, 60B, and thus twenty-five percent or less of the cavities 52 are located in the second region 62A, 62B. As another example, one hundred percent of the cavities 52 are located in the first region 60A, 60B, and in this embodiment, no portion 44A, 44B of the cavities 52 is located in the second region 62A, 62B. Therefore, in certain embodiments, the majority of the cavities 52 is still defined because the entire cavity 52 is located in the first region 60A, 60B.

[0055] The majority of the portion 44A, 44B of the weight element 42A, 42B may be ninety percent or more in the second region 62A, 62B. In certain embodiments, the majority of the portion 44A, 44B of the weight element 42A, 42B may be one hundred percent in the second region 62A, 62B, and in this embodiment, no portion 44A, 44B of the weight element 42A, 42B is disposed in the first region 60A, 60B. As shown in the Fig. 4-8, no portion 44A, 44B of the weight member 42A, 42B is disposed in the first region 60A, 60B. Therefore, in certain embodiments, the majority of the portion 44A, 44B of the weight member 42A, 42B is further defined as the entire portion 44A, 44B of the weight member 42A, 42B disposed in the second region 62A, 62B.

[0056] Continuing with the Fig.4-8, the plane 58A also divides the drive element 26B of the first shaft 28 into two halves; thus, a segment of the drive element 26B of the first shaft 28 can be disposed in the first region 60A of the first shaft 28 and a remaining segment of the drive element 26B of the first shaft 28 can be disposed in the second region 62A of the first shaft 28. Likewise, the plane 58B divides the drive element 26C of the second shaft 32 into two halves; thus, a segment of the drive element 26C of the second shaft 32 can be disposed in the first region 60B of the second shaft 32 and a remaining segment of the drive element 26C of the second shaft 32 can be disposed in the second region 62B of the second shaft 32.

[0057] Although the best modes and other embodiments for carrying out the disclosure have been described in detail, those skilled in the art will readily recognize that there are various alternative designs and embodiments for practicing the disclosure that are within the scope of the appended claims. Moreover, the embodiments illustrated in the drawings or the features of various embodiments mentioned in this description are not necessarily to be construed as independent embodiments. Rather, it is possible that each of the features described in one example of an embodiment may be combined with one or more other desired features from other embodiments to result in other embodiments not described in words or by reference to drawings.Accordingly, such other embodiments fall within the scope of the appended claims.

Claims

[1] Crankshaft balancing arrangement (14), comprising: a crankshaft (18) rotatable about a longitudinal axis; a drive element (26A) fixed to the crankshaft; a first shaft (28) rotatable about a first axis of rotation, wherein the first shaft is rotatable in response to rotation of the crankshaft; a weight member (42A) extending from the first shaft, the weight member positioned along the first shaft to balance the crankshaft during rotation of the crankshaft and the first shaft; a first drive element (26B) and a second drive element (48), wherein the first shaft and a portion (44A) of the weight element (42A) are each part of the first drive element (26B) and the second drive element (48); and wherein the first and second drive elements of the first shaft each define a cavity (52) opposite the portion of the weight element, wherein the first shaft (28) has a first end and a second end spaced apart along the first axis of rotation, and the first shaft (28) defines a length (40A) between the first and second ends of the first shaft; the first shaft is arranged along a plane (58A, 58B) and the plane (58A, 58B) contains the first axis of rotation axially with respect to the length of the first shaft to divide the first shaft (28) into two halves to define a first region and a second region; and wherein a major portion of the cavity (52) is disposed in the first region and a major portion of the portion (44A) of the weight element (42A) is disposed in the second region, wherein the cavity (52) is further defined as a plurality of cavities spaced apart from one another, each of the cavities being opposite the portion (44A) of the weight member (42A), wherein the cavities (52) are elongated. [2] The assembly of claim 1, wherein the majority of the portion (44A) of the weight member (42A) is defined wider than the entire portion of the weight member disposed in the second region. [3] An assembly according to claim 2, wherein the cavities are arranged completely through the first drive member and the second drive member of the first shaft. [4] An assembly according to claim 1, wherein the first drive member of the crankshaft and the drive member of the first shaft mesh with each other such that rotation of the first shaft is driven by rotation of the crankshaft. [5] Arrangement according to claim 4: further comprising a second shaft (32) rotatable about a second axis of rotation in response to the rotation of the first shaft (28), such that the rotation of the second shaft is driven by the rotation of the first shaft (28); and wherein the longitudinal axis, the first axis of rotation and the second axis of rotation are spaced apart from one another and substantially parallel to one another. [6] Arrangement according to claim 1: further comprising a second shaft (32) rotatable about a second axis of rotation in response to rotation of the crankshaft; a drive member (26C) surrounding the second shaft (32); and wherein the longitudinal axis, the first axis of rotation, and the second axis of rotation are spaced apart from each other and substantially parallel to each other. [7] The assembly of claim 1, wherein the cavity is partially defined by the first drive member (26B) and the second drive member (48) of the first shaft such that the drive member has a side wall and a base wall defining the cavity. [8] Powertrain (10), comprising: a housing (12); a crankshaft balancer assembly (14) disposed at least partially within the housing, and wherein the crankshaft balancer assembly comprises: a crankshaft (18) rotatable about a longitudinal axis; a drive element attached to the crankshaft; a first shaft (28) rotatable about a first axis of rotation, wherein the first shaft (28) is rotatable in response to rotation of the crankshaft; a weight member (42A) extending from the first shaft, the weight member positioned along the first shaft to balance the crankshaft during rotation of the crankshaft and the first shaft; a first drive element (26B) and a second drive element (48), wherein the first shaft and a portion (44A) of the weight element (42A) are each part of the first drive element (26B) and the second drive element (48); and wherein the first and second drive members of the first shaft each define a plurality of cavities opposite the portion (44A) of the weight member (42A), wherein the first shaft (28) has a first end and a second end spaced apart along the first axis of rotation, and the first shaft defines a length between the first and second ends of the first shaft; the first shaft (28) is arranged along a plane (58A, 58B), and the plane (58A, 58B) contains the first axis of rotation axially with respect to the length of the first shaft to divide the first shaft into two halves to define a first region and a second region; and wherein a majority of the plurality of cavities is disposed in the first region and a majority of the portion (44A) of the weight member (42A) is disposed in the second region wherein the cavity (52) is further defined as the plurality of cavities spaced apart from one another, each of the cavities being opposite the portion (44A) of the weight member (42A), the cavities (52) being elongated.

Images