Shift actuator

Abstract

A shift actuator may have: a housing having at least one curved groove; a sleeve at least partially within the housing; a motor located at least partially within the sleeve; the gear reduction assembly is located in the sleeve and rotationally connected with the motor; and a rotary output member connected to the gear reduction assembly, where the rotary output member extends at least partially into the slot.

Description

Technical Field

[0001] A gear shift actuator is disclosed, which may be suitable for moving a drive device. The gear shift actuator may be used in a vehicle, such as a transmission or drive train of the vehicle. Background Art

[0002] Shift actuators are known devices that can be used to move components in, for example, a transmission or drivetrain in a vehicle. Current shift actuators suffer from several drawbacks. For example, current shift actuators have too many parts. These parts must come from different suppliers, which can lead to supply chain issues. Furthermore, the numerous parts each present multiple failure modes for the actuator. Furthermore, current shift actuators are inefficient, in part due to their numerous parts and the numerous connections between the parts, which results in power losses and thus inefficiencies. Furthermore, the large number of parts also makes current shift actuators bulky, making them heavy and difficult to handle during installation and transportation, and furthermore, they take up a significant amount of space in an already crowded environment that could be used for other components.

[0003] In view of the shortcomings associated with current shift actuators, it would be advantageous to have a shift actuator that minimizes the number of parts, utilizes power efficiently, and is compact and lightweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The foregoing and other advantages will become apparent to those skilled in the art upon consideration of the following detailed description in light of the accompanying drawings, in which:

[0005] Figure 1 is a schematic side view of an embodiment of a shift actuator;

[0006] Figure 2 is a schematic cross-sectional side view of a shift actuator;

[0007] Figure 3 is a schematic side view of components of a shift actuator;

[0008] Figure 4 is a schematic exploded side view of components of a shift actuator;

[0009] Figure 5 FIG. 1 is a schematic side view of a shift actuator in one embodiment of a transmission in a neutral state and with Figure 1 The shift actuator positions shown are associated;

[0010] Figure 6 is a schematic side view of a shift actuator in one embodiment of a transmission, the transmission being in a first engaged state;

[0011] Figure 7is a schematic side view of an embodiment of a shift actuator in a position Figure 6 a position associated with a first engaged state of the transmission;

[0012] Figure 8 is a schematic side view of one embodiment of a shift actuator in a position associated with a second engaged state of the transmission. DETAILED DESCRIPTION

[0013] It should be understood that the present apparatus may adopt various alternative orientations and step sequences unless expressly stated to the contrary. It should also be understood that the specific apparatus and methods shown in the accompanying drawings and described in the following specification are merely simple exemplary embodiments of the concepts herein. Thus, unless expressly stated otherwise, specific dimensions, directions, or other physical characteristics related to the disclosed embodiments should not be considered limiting.

[0014] Now go to Figure 1-Figure 4 , schematically illustrates one embodiment of a shift actuator 10. The shift actuator 10 may include a housing 12. The housing 12 may be a one-piece, integrally formed, and unitary housing 12, or the housing 12 may be constructed from one or more pieces or components.

[0015] In some embodiments, housing 12 can have a circular or polygonal cross-section. As shown, housing 12 can be generally tubular, having a curved outer surface 14 and a curved inner surface 16 that is complementary in shape to outer surface 14. These two surfaces 14 and 16 can be separated from each other by a generally constant thickness of housing 12. Inner surface 16 can define a generally constant inner diameter 18 and an internal void space 20. Outer surface 14 can define a generally constant outer diameter 22.

[0016] The housing 12 may also have a first end 24, a first end 26, a second end 28, and a second end 30. A main body portion 32 of the housing 12 may extend between the first end 26 and the second end 30. Since the housing 12 is tubular, the first end 26 and the second end 30 may be open.

[0017] The housing 12 can be substantially continuous, except that at least one slot can be located in at least one of the ends 24 and 28. In one embodiment, the at least one slot can be generally located in the second end 28. A first slot 34 and a second slot 36 can be present, both located in the second end 28. The slots 34 and 36 can be disjoint or located on opposing sides or hemispheres of the housing 12. The slots 34 and 36 can be equally spaced about the housing 12. Each slot 34 and 36 can have a curved path, such as an at least partially helical path, extending along and completely through the housing 12. In some cases, the path of each slot 34 and 36 can be substantially identical, and the slots 34 and 36 can have the same pitch. In one embodiment, the slots 34 and 36 can extend along the housing 12 from a first longitudinal position 38 near the first end 26 to a second longitudinal position 40 near the second end 30. In other embodiments, more than two slots can be used.

[0018] The housing 12 may also have an opening 37 in the first end 24. This opening may receive a rotational locking device 39 from an inner sleeve (described below).

[0019] In some cases, the inner sleeve 42 can be at least partially located within the interior void space 20. The inner sleeve 42 can extend within the housing 12 along at least a portion of the length of the housing 12. Figure 2 In the illustrated embodiment, the sleeve 42 may terminate before it reaches the second end 30 of the housing 12. This may leave a gap 44 between the second end 46 of the sleeve 42 and the second end 30 of the housing 12. The first end 48 of the sleeve 42 may extend beyond the first end 24 of the housing 12. The first end 48 of the sleeve 42 may terminate at a first end 50.

[0020] The first end 50 can be connected to a second end 52 of a radially extending bolt flange 54. The bolt flange 54 can have a diameter 58 that is greater than the outer diameter 22 of the housing 12. The bolt flange 54 can be unitary, one-piece, and integrally formed with the sleeve 42. The bolt flange 54 can have a hollow interior 56 that extends from the second end 52 to the first end 58.

[0021] An electrical conductor 60 may be connected to the first end 58. The electrical conductor 60 may be connected to a circuit board 61. The electrical conductor 60 and / or the circuit board 61 may be connected to a motor 62 to control the motor 62.

[0022] At least a portion of the inner sleeve 42 can have a circular or polygonal cross-section. As shown, the inner sleeve 42 can be at least partially tubular, having a curved outer surface 64 and a curved inner surface 66 that is complementary in shape to the outer surface 64. The two surfaces 64 and 66 can be at least partially separated from each other by a generally constant thickness of the inner sleeve 42. The inner surface 66 can define a generally constant inner diameter 68 and an internal void space 70.

[0023] The diameter 72 of the outer surface 64 of the inner sleeve 42 may be slightly smaller than the diameter 18 of the inner surface 16 of the housing 12 such that the sleeve 42 may be at least partially located within the interior void 20 of the housing 12 .

[0024] In one embodiment, the motor 62 can be positioned within the first end 48 of the inner sleeve 42 within the interior void 70 of the sleeve 42. The motor 62 can be secured against rotational and axial movement relative to the sleeve 42. The motor 62 can be an electric motor connected to a circuit board 61 and a power source (not shown). The motor 62 can be positioned within the inner sleeve 42 such that a longitudinal axis 74 of the motor 62, including an output shaft 76 of the motor 62, is colinear or coaxial with a longitudinal axis 78 of the shift actuator 10. The output shaft 76 can be adapted to rotate in both a clockwise and counterclockwise direction.

[0025] The output shaft 76 of the motor 62 may be connected to a gear set 80 or gear box (which may include a gear set), which may also be located within the inner sleeve 42 .

[0026] In one embodiment, the motor output shaft 76 can be connected to a sun gear 82 of a gear set 80. As one example, the sun gear 82 can be mounted on the output shaft 76, such as in a concentric manner.

[0027] Gear set 80 may be, for example, a reduction gear set. Gear set 80 may further include a plurality of planetary gears 84, wherein outer diameter teeth 86 of planetary gears 84 mesh with outer diameter teeth 88 of sun gear 82. Outer diameter teeth 86 of planetary gears 84 may also mesh with a first ring gear 90. Planetary gears 84 and sun gear 82 may form a first planetary gear set 92. Planetary gears 84 may be mounted on shafts 94 extending longitudinally from a carrier 98.

[0028] The carrier 98 may have a stub shaft 100 extending along the longitudinal axis 78, wherein the stub shaft 100 carries teeth for a second sun gear 102 of a second planetary gear set 104. The second planetary gear set 104 may also include a plurality of planet gears 106, with outer diameter teeth 108 of the planet gears 106 meshing with outer diameter teeth 110 on the sun gear 102. The outer diameter teeth 108 of the planet gears may also mesh with a second ring gear 112. The planet gears 106 may be mounted on a shaft 114 extending longitudinally from a first side 116 of a second carrier 118.

[0029] The bracket 118 can have a longitudinally extending stub shaft 120. The stub shaft 120 can extend longitudinally from a second side 122 of the bracket 118. The stub shaft 120 can be mounted for at least rotation within the sleeve 42 and can extend longitudinally into at least a portion of the housing 12. The stub shaft 120 can be supported within the sleeve 42 by at least one bearing 124 including an inner race 126, an outer race 128, and a plurality of ball bearings 130 between the inner races 126, 128. A seal 132 can be positioned longitudinally adjacent to the bearing 124 to prevent lubricant from leaking from the hollow interior 70 of the sleeve 42 and to prevent contaminants from penetrating the hollow interior 70 of the sleeve 42.

[0030] The reduction gear set 80 can be designed to reduce the number of revolutions of the motor output shaft 76 to a predetermined number of revolutions. The predetermined number of revolutions can be less than the number of revolutions of the motor output shaft 70. In one embodiment, the reduction ratio between the motor output shaft 76 and the gear set 80 can be, for example, 40:1.

[0031] The stub shaft 120 can have at least one rotational output member 134 extending transversely therefrom. The member 134 can be rod-shaped and have a circular cross-section, although other geometric shapes are also possible. In one embodiment, the members 134 can be two pins extending from the stub shaft 120. The pins 134 can extend generally perpendicular to the longitudinal axis 78 and can extend generally opposite each other, for example, offset from the stub shaft 120 by approximately 180 degrees. In another embodiment, the rotational output member 134 can be, for example, a single pin or rod. In this case, the rotational output member 134 can be a single piece, integrally formed, or unitary.

[0032] Pin 134 can extend into slots 34, 36 of housing 12. In some cases, a friction reducing device 136, such as a roller or low-friction bushing, can be located on pin 134 at the location where pin 134 extends into slots 34, 36. Friction reducing device 136 can contact sidewalls 138 that define the openings of slots 34, 36 and facilitate movement between friction reducing device 136 and slots 34, 36.

[0033] In some cases, a drive device 140 can be coupled to the outer surface 14 of the housing 12. The drive device 140 can be, for example, a shift fork or a shift collar. The drive device 140 can extend generally transverse to the outer surface 14 and can be fixedly coupled to the housing 12 so that it moves therewith.

[0034] In one embodiment of the operation of the actuator 10, power is supplied to the motor 62, which provides rotational energy to the first sun gear 82 of the first set of planetary gears 84. The sun gear 82 rotates the planetary gears 84 relative to the stationary first ring gear 90. This causes the carrier 98 to which the planetary gears 84 are attached to rotate. A second sun gear 102, attached to the carrier 98, rotates with the carrier 98 and provides a rotational input to the second planetary gear set 104.

[0035] The rotation of the second sun gear 102 rotates the second planetary gear set 104 within the second fixed ring gear 112. The second planetary gear set 104, mounted on the second carrier 118, rotates the carrier 118 and its stub shaft 120.

[0036] The stub shaft 120 rotates the member 134. While a single member 134 can be used, multiple members 134 provide for evenly distributed force, making the use of multiple members 134 preferred. As described above, the member 134 can be designed to slide within angled (or at least partially helical) grooves 34, 36 in the housing 12. As the member 134 slides within the helical grooves 34, 36, an axial force is generated, causing the housing 12 to rotate and translate along the longitudinal axis 78. Grooves 34, 36, having substantially the same size, shape, and pitch, produce the same longitudinal translation of the housing 12 for a given rotation of the rotary output member 134. As will be readily appreciated, structures attached to the housing 12 will also produce longitudinal motion.

[0037] Circuit board 61 may be adapted to monitor sensor target 142. When circuit board 61 notices that sensor target 142 has reached a desired position, circuit board 61 will stop rotation of motor 62. Although circuit board 61 is mentioned, circuit board 61 may be omitted and other control devices may be used.

[0038] It will be appreciated that rotation of the motor 62 in a first direction moves the drive device 140 in the first direction along the longitudinal axis 78, while rotation in a second direction opposite the first direction moves the drive device 140 in the second direction along the longitudinal axis 78. For example, Figure 7 Schematically illustrating a housing that has been displaced in a first direction. And, Figure 8 The housing is schematically shown displaced in the second direction. From both figures it can be easily seen that the drive devices attached to the housing move respectively.

[0039] In some cases, sensor 144 may be located on or within inner sleeve 42, or on or within motor 62. Sensor 144 may be adapted to detect sensor target 142. Target 142 may be a magnet or related device detectable by sensor 144. For example, the target may be located on drive device 140 or housing 12. This allows for highly accurate readings of the drive device's position. In other cases, no sensor is required.

[0040] Now go to Figure 5 and Figure 6 , which schematically illustrates a shift actuator 10 positioned within one embodiment of a transmission 146. As can be seen from the figure, the shift actuator 10 can move the drive device 140 between at least three positions: neutral, a first shift position, and a second shift position. In the neutral position, the transmission 146 has no power flowing from the input side 148 of the transmission 146 to the output side 15. The actuator 10 can be in, for example, Figure 1 The state shown is to achieve this effect in the transmission.

[0041] When the drive device 140 is moved by the actuator 10, the first gear set 152 in the first shift position is engaged, causing power to flow from the input side 148 to the output side 150 of the transmission. Figure 6 The actuator 10 can be in a position such as Figure 7 The state shown is to achieve this effect in the transmission.

[0042] The actuator 10 may be in a position such as Figure 8 In the state shown, the rotary power from the input side 148 is connected through the second gear set 154.

[0043] Therefore, it can be understood from the above that the shift actuator 10 can also move the driving device 140 from the neutral drive to the second shift position, or from the first shift position to the second shift position, and vice versa.

[0044] A signal can be provided to the shift actuator 10 via a communication system, which can be wired and / or wireless, to initiate the shift. This signal can be provided to the circuit board 61 and / or the motor 62. The circuit board 61 can monitor the position of the drive device 140 and, through the sensor 144 and the sensor target 142, the circuit board 61 can determine, for example, whether the drive device 140 is in a neutral position, a pre-engaged position, or engaged in the first or second shift position. The circuit board 61 turns on one or more transistors (which can be part of an H-bridge design) and allows current to flow into the motor 62 in the direction to initiate the desired movement.

[0045] As will be appreciated from the foregoing, by locating at least the motor 62 and the gear set 80 in a single compact housing 12, significant space savings and a reduced number of parts are achieved compared to the prior art. Other significant drawbacks of the prior art are also overcome.

[0046] In accordance with the provisions of the patent statutes, the apparatus has been described in what is considered to represent its preferred embodiment. However, it should be noted that the apparatus can be practiced otherwise than as specifically shown and described without departing from its spirit or scope.

Claims

1. A gear shift actuator, comprising: a longitudinally translatable housing having at least one curved slot in an outer surface; a non-rotatable sleeve at least partially located within the housing; a motor at least partially positioned within the sleeve, the motor having a rotatable output shaft longitudinally aligned with the actuator axis; a gear reduction assembly positioned within the sleeve and rotationally connected to the output shaft; as well as A rotational output member is connected to the gear reduction assembly, wherein the rotational output member extends at least partially into the slot.

2. The shift actuator according to claim 1, characterized in that: The housing is tubular and has a first end, a first end portion, a second end, and a body portion located between the ends, wherein the slot is located at the second end portion, and wherein the sensor and the sensor target are located near the first end portion.

3. The shift actuator according to claim 1, characterized in that The outer surface of the housing is curved, and the slot extends through the housing from a first longitudinal position to a second longitudinal position along the outer surface of the housing.

4. The shift actuator according to claim 2, characterized in that: The first end of the sleeve extends longitudinally beyond the first end of the housing, and the second end of the sleeve is radially covered by the second end of the housing, and the sleeve terminates longitudinally before reaching the slot in the housing.

5. The shift actuator according to claim 1, characterized in that The gear reduction assembly includes a first gear reduction assembly longitudinally connected to a second gear reduction assembly.

6. The shift actuator according to claim 5, characterized in that: The first gear reduction assembly includes a first sun gear on the motor output shaft and a plurality of planet gears meshing with the first sun gear and a ring gear in the sleeve, wherein the planet gears are located on a first side of a first carrier.

7. The shift actuator according to claim 6, characterized in that: The carrier has a stub shaft extending from a second side, wherein the stub shaft has a second sun gear of the second gear reduction assembly coupled thereto.

8. The shift actuator according to claim 7, characterized in that: The second gear reduction assembly has a plurality of planet gears meshing with the second sun gear and the second ring gear, the plurality of planet gears being carried on a first side of a second carrier.

9. The shift actuator according to claim 8, characterized in that The second bracket has a stub shaft extending from a second side, wherein the rotation output member is connected to the stub shaft to rotate therewith.

10. The shift actuator according to claim 9, characterized in that The rotational output member is a radially extending rod extending into the at least one slot.

11. The shift actuator according to claim 1, characterized in that A shift fork or shift collar is fixedly connected to the outer surface of the housing.

12. The shift actuator according to claim 1, characterized in that The housing has an inner surface having a shape complementary to the outer surface, wherein the inner surface has a first radius and the outer surface has a second radius greater than the first radius, wherein a substantially constant thickness is defined between the first radius and the second radius, and the slot extends completely through the thickness.

13. The shift actuator according to claim 1, wherein: The at least one curved slot is a first slot, and a second slot having substantially the same length as the first slot is located in the rotatable housing opposite the first slot.

14. The shift actuator according to claim 1, wherein: The rotatable housing is generally cylindrical and is at least partially concentric relative to the non-rotatable sleeve, which is also generally cylindrical, and wherein the motor is at least partially concentric with the non-rotatable sleeve.

15. The shift actuator according to claim 10, characterized in that A low friction structure extends around the end of the radially extending rod, the low friction structure at least partially engaging a wall of at least one slot.

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