阅读说明：本技术 闩锁组件 (Latch assembly ) 是由 朱利安·雷亚 塞德里克·基特尔斯 贾斯汀·兰多恩 于 2021-06-22 设计创作，主要内容包括：一种用于车辆的应用在诸如扶手控制台或手套箱中的闩锁组件,包括形状记忆合金(SMA)致动器。SMA致动器包括致动器壳体、SMA线和致动器杠杆臂。致动器杠杆臂配置为在SMA线激活时相对于致动器壳体可枢转地旋转或线性地平移。连接杆联接至致动器杠杆臂。连接杆配置为当致动器杠杆臂可枢转地旋转或线性地平移时沿着连接杆轴线线性地平移。撞针联接至连接杆并配置为围绕撞针轴线旋转以接合闭合表面。(A latch assembly for a vehicle application, such as in an armrest console or glove box, includes a Shape Memory Alloy (SMA) actuator. The SMA actuator includes an actuator housing, an SMA wire, and an actuator lever arm. The actuator lever arm is configured to pivotally rotate or linearly translate relative to the actuator housing upon activation of the SMA wire. The connecting rod is coupled to the actuator lever arm. The connecting rod is configured to linearly translate along the connecting rod axis when the actuator lever arm is pivotally rotated or linearly translated. The striker is coupled to the connecting rod and configured to rotate about a striker axis to engage the closure surface.)

1. A latch assembly, comprising:

a shape memory alloy actuator having an actuator housing, a shape memory alloy wire, and an actuator lever arm, wherein the actuator lever arm is configured to pivotally rotate or linearly translate relative to the actuator housing when the shape memory alloy wire is activated;

a connecting rod coupled to the actuator lever arm, wherein the connecting rod is configured to linearly translate along a connecting rod axis when the actuator lever arm is pivotally rotated or linearly translated; and

a striker coupled to the connecting link, wherein the striker is configured to rotate about a striker axis to engage a closure surface.

2. The latch assembly of claim 1, wherein the connecting rod includes a wrapped end to couple the actuator lever arm.

3. The latch assembly of claim 1, wherein at least a portion of the shape memory alloy wire extends parallel to an actuator housing axis that extends along a longest length of the actuator housing.

4. The latch assembly of claim 1, wherein the actuator lever arm is configured to pivotably rotate relative to the actuator housing.

5. The latch assembly of claim 4, wherein the actuator lever arm has an actuation range of pivotable rotation between 10 ° and 25 °, and including 10 ° and 25 °.

6. The latch assembly of claim 5, wherein the actuation range overlaps an actuator lever arm axis, and the actuator lever arm axis is perpendicular to an actuator housing axis extending along a longest length of the actuator housing.

7. The latch assembly of claim 1, wherein an actuator housing axis extending along a longest length of the actuator housing is aligned with the connecting rod axis.

8. The latch assembly of claim 7, wherein the actuator lever arm translates linearly when the shape memory alloy wire is activated.

9. The latch assembly of claim 1, comprising a decoupling interface between the striker and the shape memory alloy actuator, wherein the decoupling interface decouples movement of the striker from movement of the shape memory alloy wire.

10. The latch assembly of claim 9, wherein the shape memory alloy actuator includes a return spring, and wherein the decoupling interface allows the return spring and the shape memory alloy wire to return to an initial position at different rates.

11. The latch assembly of claim 1, wherein the striker includes a pawl and a linking extension.

12. The latch assembly of claim 12, wherein the connecting extension has an open track to slidably receive the connecting rod.

13. A center console for a vehicle comprising the latch assembly of claim 1.

14. The center console of claim 13, wherein the closure surface is located on an armrest.

15. A glove box for a vehicle comprising the latch assembly of claim 1.

Technical Field

The present invention relates generally to latch assemblies for vehicles and, more particularly, to latch assemblies utilizing Shape Memory Alloy (SMA) actuators.

Background

Shape Memory Alloy (SMA) actuators may be used to facilitate movement of one or more components in a latch assembly. For example, U.S. patent 10435918 to Weber et al discloses a latch system that includes SMA wires that contract when an electric current is applied to the SMA wires. Contraction of the SMA wire pulls the rocker and ultimately rotates the engagement element to open the storage compartment. Strategic decoupling of the interface between the engagement element or striker and the SMA wire may improve the performance of the latch assembly.

Disclosure of Invention

An example latch assembly for a vehicle includes a Shape Memory Alloy (SMA) actuator having an actuator housing, an SMA wire, and an actuator lever arm. The actuator lever arm is configured to pivotally rotate or linearly translate relative to the actuator housing upon actuation of the SMA wire. The connecting rod is coupled to the actuator lever arm. The connecting rod is configured to linearly translate along the connecting rod axis when the actuator lever arm is pivotally rotated or linearly translated. The striker is coupled to the connecting link and is configured to rotate about a striker axis to engage the closure surface.

In some embodiments, the connecting rod includes a wrapping end to couple the actuator lever arm.

In some embodiments, at least a portion of the Shape Memory Alloy (SMA) wire extends parallel to an actuator housing axis that extends along the longest length of the actuator housing.

In some embodiments, the actuator lever arm is configured to pivotally rotate relative to the actuator housing.

In some embodiments, the actuation range of pivotable rotation of the actuator lever arm is between 10 ° and 25 °, including 10 ° and 25 °.

In some embodiments, the actuation range overlaps the actuator lever arm axis, and the actuator lever arm axis is perpendicular to the actuator housing axis.

In some embodiments, the actuator housing axis is aligned with the connecting rod axis.

In some embodiments, the actuator lever arm translates linearly upon activation of a Shape Memory Alloy (SMA) wire.

In some embodiments, there is a decoupling interface between the striker and the Shape Memory Alloy (SMA) actuator, and the decoupling interface decouples motion of the striker from motion of the SMA wire.

In some embodiments, the Shape Memory Alloy (SMA) actuator includes a return spring, and the decoupling interface allows the return spring and the SMA wire to return to an initial position at different rates.

In some embodiments, the striker includes a locking pawl and a connecting extension.

In some embodiments, the connection extension has an open track to slidably receive the connection rod.

In some embodiments, a center console for a vehicle includes a latch assembly.

In some embodiments, the closure surface is located on the armrest.

In some embodiments, a glove box for a vehicle includes a latch assembly.

It is contemplated that any number of the individual features of the above-described embodiments and any other embodiments described in the figures or the following description may be combined in any combination to define the invention, except where the features are incompatible.

Drawings

Exemplary embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:

FIG. 1 is a perspective view of the interior of a vehicle passenger compartment showing various storage compartments fitted with latch assemblies;

FIG. 2 illustrates the interior of the armrest center console and the latch assembly of FIG. 1;

FIG. 3 is a side view of the connecting rod and striker of the latch assembly;

FIG. 4 illustrates a Shape Memory Alloy (SMA) actuator of the latch assembly of FIGS. 1 and 2;

FIG. 5 illustrates one embodiment of an actuator housing of an SMA actuator; and

FIG. 6 illustrates another embodiment of an SMA actuator lever arm.

Detailed Description

Embodiments of latch assemblies for various vehicle-based applications (such as with consoles, armrests, glove boxes, other storage compartments), and other implementations such as headrests, are described herein. The latch assembly strategically employs Shape Memory Alloy (SMA) wires in the SMA actuator that cooperate with a connecting rod and a striker to facilitate, for example, opening and/or closing of a vehicle compartment. The SMA actuators disclosed herein may provide a cost effective solution that also improves packaging and noise. For example, the latch assemblies described herein with SMA actuators may be quieter, lighter, and smaller than solenoid actuators. The arrangement and operability of the various components of the SMA actuator may improve the performance of the latch assembly. The strategic decoupling interface between the SMA actuator and the striker of the latch assembly allows the return spring and SMA wire to return to their initial positions at different rates without moving the striker. Furthermore, the temporary movement of the striker pin when the storage compartment is closed does not affect the SMA actuator.

FIG. 1 is a perspective view of the interior of a passenger compartment 10 of a vehicle 12, the vehicle 12 including various types of storage compartments that may use the latch assembly described herein. The exemplary storage compartment includes a center console 14 having an armrest 16 and a glove box 18; however, the latch assembly of the present disclosure may also be used in other implementations. Further, while the present disclosure focuses more on the latch assembly being used with the center console 14 and armrest 16, various features and attributes of the latch assembly may also be used and may be adapted for use with other storage compartments such as glove box 18 or other actuatable components.

Fig. 2 shows a latch assembly 20. In fig. 2, the front cover is removed from the center console 14 to show the interior area 22 housing the latch assembly 20. The latch assembly 20 includes an SMA actuator 24, the SMA actuator 24 including an actuator housing 26, an SMA wire 28 located within the actuator housing 26, and an actuator lever arm 30. The actuator lever arm 30 is configured to pivotally rotate or linearly translate relative to the actuator housing 26 upon activation of the SMA wire 28. A connecting rod 32 is coupled to the actuator lever arm 30 and a striker 34 is coupled to the connecting rod 32. As used herein, "coupled" may be directly coupled (where one component is fixedly or directly attached to another component) or may be indirectly coupled (where one or more other subcomponents are located therebetween) to facilitate attachment, for example. In addition, "coupled" may also include arrangements in which one component is carried on another component.

In operation, when a user wishes to open the armrest 16 to access the storage compartment 36 in the center console 14, they may press a button or some other trigger, actuation device, or the like, which will ultimately cause an electrical current to be applied to the SMA wire 28. As the SMA wire 28 contracts, the SMA wire 28 moves the actuator lever arm 30. The actuator lever arm 30 pulls the connecting rod 32, which rotates the striker 34. The striker 34 engages a closure surface 38 on the inside of the armrest 16. The closure surface 38 may include a small recess, alcove, pocket, or the like for receiving the striker 34. In the illustrated embodiment, the armrest 16 includes two panels 40, 42. In other embodiments, there may be only one panel, or more than two panels. The latch assembly 20 operates to facilitate opening and/or securely closing the first panel 40. A second latch assembly may be included to facilitate opening and/or secure closing of the second panel 42, or there may be one latch assembly securing both panels 40, 42. Other arrangements with covers are of course possible.

Fig. 3 illustrates the movement of the connecting rod 32 and the striker 34 during operation of the latch assembly 20. The connecting rod 32 is configured to be pivotally rotated or linearly translated along a connecting rod axis a when the actuator lever arm 30 (not shown in fig. 3) is pivotally rotated or linearly translated_CLinearly translated. This causes the striker 34 to surround the striker axis A_SRotating to engage the closure surface 38. Connecting rod axis A_CExtending along the longest length or extent of the connecting rod 32. Striker axis A_SExtending through the center of rotation of the striker 34. In the illustrated embodiment, the connecting rod axis A_CGenerally aligned with the striker axis A_SAnd is vertical. The connecting rod 32 and the striker 34 are relative to the axis A_CAnd A_SIs facilitated by the SMA actuator 24.

Fig. 4 illustrates one embodiment of an SMA actuator 24 that may be used with the latch assembly 20 shown in fig. 2. The SMA actuator 24 is positioned in communication with the connecting rod 32 such that the force applied by the SMA actuator 24 ultimately moves the striker 34 and provides access to the storage compartment 36. Thus, the connecting rod 32 helps to form a decoupling interface 44 between the SMA actuator 24 and the striker 34. In addition, the movement of the actuator lever arm 30 also helps to form a decoupling interface 44 between the SMA wire 28 and the striker 34.

The SMA actuator 24 includes an actuator housing 26, an SMA wire 28, and an actuator lever arm 30. One embodiment of the actuator housing 26 is shown in FIG. 5. The actuator housing 26 includes two longitudinally extending side walls 46, 48 joined by a plurality of ribs 49. The ribs 49 provide further support for the body of the SMA actuator 24. In some embodiments, the ribs 49 support a Printed Circuit Board (PCB)50 (see, e.g., PCB50 in fig. 4) to which the SMA wires 28 are mounted. One or more backing plates 52 (shown in fig. 2) may be mounted to the actuator housing 26 to help shield internal components (such as the PCB50 and the SMA wire 28). Screw holes 54 may be used to attach the back plate 52, and one or more locating pins 56 may provide a physical reference for ease of assembly. The actuator housing 26 may be made of a rigid plastic or some other operable material. In some embodiments, the actuator housing 26 may simply be the PCB50 or some other component to which the other components of the SMA actuator 24 are attached.

The SMA wire 28 is composed of a shape memory alloy material whose length varies depending on the temperature of the material. Thus, when current is applied to the SMA wire 28, the SMA wire 28 heats up and contracts, which pulls the actuator lever arm 30. The shape memory alloy material reversibly switches material states (e.g., between martensite and austenite) to cause contraction and movement of the actuator lever arm 30. Cooling of the SMA wire 28 returns the wire to its original position. An initial position 58 and a retracted position 60 shown in phantom are shown in fig. 4. Two exemplary shape memory alloy materials that may be used for the SMA wire 28 include copper-aluminum-nickel and nickel-titanium; however, other shape memory alloy materials are of course possible.

The SMA wires 28 are mounted on the PCB50 such that the SMA wires 28 are loopedAround or otherwise attached to the anchor 62 on the actuator lever arm 30. At least a portion of the SMA wire 28 is aligned with the actuator housing axis a_HExtending in parallel. The anchor 62 for coupling the SMA wire 28 to the actuator lever arm 30 is a washer; however, other ways of anchoring the SMA wire 28 to the actuator lever arm 30 are of course possible. When the SMA wire 28 contracts, the anchor 62 is pulled by the SMA wire 28 and the actuator lever arm 30 rotates at the pivot point 64. Thus, the actuator lever arm 30 is configured as an output stage lever arm to pivotally rotate relative to the actuator housing 26 upon activation of the SMA wire 28. The actuation range 66 of pivotable movement of the actuator lever arm 30 is at least partially defined by a return spring 68 and an end stop 70. The return spring 68 is a biasing spring that assists in the retraction of the actuator lever arm 30 and SMA wire 28 when the voltage is off. The pivotable rotational actuation range 66 of the actuator lever arm 30 is advantageously between 10 ° and 25 ° and includes 10 ° and 25 °. In the illustrated embodiment, the actuation range 66 is 14 °. Actuation range 66 and actuator lever arm axis A_LOverlapping, actuator lever arm axis A_LIs an axis that longitudinally separates the actuator lever arm 30 along its longest length or extent when the actuator lever arm 30 is in its initial position 58. Actuator lever arm axis A_LIn the initial position 58 and the actuator housing axis A_HAnd is vertical. Additionally, in the initial position 58, the anchor 62 and the pivot point 64 are both along the actuator lever arm axis a_LAnd (6) aligning. This arrangement (in which the actuator lever arm axis A is_LAt an initial position 58 with the actuator housing axis a_HVertical) may improve the installation of the latch assembly 20. Further, the actuator lever arm 30 is oriented along an actuator lever arm axis A_LExtending vertically from the actuator housing 26 may facilitate adjusting the force output while maintaining a small, thin overall package to fit into a compact area.

In this embodiment, the SMA wire 28 contracts a few millimeters (about 3% -5% of its length) when actuated. Actuation of the SMA wire 28 may be triggered by a button on the center console 14, a button on the dashboard, or by some other operable means (e.g., voice activation). The SMA actuators 24 and SMA wires 28 may be supplied with power by a vehicle power supply or by a separate low voltage battery, to name a few examples. The arrangement of the actuator lever arm 30 relative to the actuator housing 26 and SMA wire 28 multiplies the stroke to achieve an output stroke of approximately 10 mm. The output force at the end of the actuator lever arm 30 is approximately 10N. After contraction, the SMA wire 28 retracts to its original position within about 5 seconds with the assistance of the return spring 68. In one exemplary embodiment, the SMA wire 28 is activated at about 3V to 15V (Vcc). Higher voltages can reduce actuation time. With Vcc connected to the ground lead, logic level signals are sent to the MOSFET transistor driver circuit. The actuator applies a desired voltage (Vcc) to the SMA wire 28. The signal may also be Pulse Width Modulated (PWM) to simulate voltages below Vcc. To help prevent the application of high voltages that can burn out the SMA wire 28, the end stop 70 and the second end stop 72 together help to electromechanically limit the applied voltage. When the actuator lever arm 30 reaches the predetermined end of its stroke or the end of the actuation range 66, the actuator lever arm 30 will contact one of the end stops 70, 72. This signals the control electronics 74, which is advantageously housed within the actuator housing 26, to momentarily stop the voltage and then reapply the voltage. This switching modulation may help prevent the SMA wire 28 from overheating. Other mechanisms for cooling the SMA wire 28 may also be included, such as a cooling jacket, heat sink, or the like.

The decoupling interface 44 between the SMA wire 28 and the striker 34 allows the SMA wire 28 to retract/extend without affecting the striker 34. This allows the return spring 68 and SMA wire 28 to return to their initial positions at different rates without affecting the latch assembly 20. Further, when the first panel 40 of the armrest 16 is closed, the striker 34 is temporarily moved until it engages a notch or the like in the closure surface 38, and the latch assembly 20 is locked again. This temporary movement does not affect the SMA actuator 24 given the decoupling interface 44. To form the decoupling interface 44, the actuator lever arm 30 is coupled to the tie rod 32, and then the tie rod 32 is coupled to the striker 34.

The connecting rod 32 has a main rod body 76 located between a winding end 78 and a striker interface end 80. The winding end 78 is operatively coupled to the actuator lever arm 30. The fastener may extend through an attachment alcove 82 located in the distal end of the actuator lever arm 30, and the arms 84, 86 of the wrapping end 78 may extend around the fastener to couple the wrapping end 78 and the actuator lever arm 30. With particular reference to fig. 3, the striker interface end 80 has an anvil-like shape that mates with the striker 34. More specifically, the striker 34 has a locking pawl 88 and a linking extension 90 extending from the locking pawl 88. The linking extension 90 has an open track 92 to slidably receive the striker interface end 80 of the linking rod 32. The arrangement of the connecting rod 32 and the striker 34 may vary from that specifically shown. For example, the connecting rod 32 may be a wire or have some other operable form. The striker 34 may have two locking pawls 88, as shown in fig. 2, or it may have 1 locking pawl 88, as shown in fig. 3, or it may have more than two locking pawls 88. Other configuration adjustments are of course possible.

Fig. 6 shows another embodiment of an SMA actuator 24'. In this embodiment, the actuator lever arm 30' is oriented along an actuator lever arm axis A_L' linearly translated, rather than oriented to pivotably rotate. Further, in this embodiment, the actuator lever arm axis A_L' all with actuator housing axis A_HAnd (4) aligning. This allows the SMA actuator 24' to pull the connecting rod 32 such that the actuator lever arm axis A_L' also with the connecting-rod axis A_CAnd (4) completely aligning. Thus, with this embodiment of the SMA actuator 24', the actuator housing axis a_HActuator lever arm axis A_L' and connecting rod axis A_CMay all be aligned or collinear during operation of the latch assembly 20.

It is to be understood that the above is a description of one or more embodiments of the invention. The present invention is not limited to the specific embodiments disclosed herein, but is only limited by the following claims. Furthermore, the statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various changes and modifications to the disclosed embodiments, as well as various other embodiments, will be apparent to persons skilled in the art upon reference to the description. All such other embodiments, variations and modifications are intended to fall within the scope of the appended claims.

As used in this specification and claims, the terms "for example (e.g.)", "for example (for example)", "for example (for instance)", "such as (sucas)" and "like" and the verbs "comprising (composing)", "having (having)", "including (including)" and their other verb forms, when used in conjunction with a list of one or more components or other items, are each to be construed as open-ended, meaning that the list is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation. Furthermore, the term "and/or" should be interpreted as an inclusive "or". Thus, for example, the phrase "A, B and/or C" should be construed to encompass all of the following: "A"; "B"; "C"; "A and B"; "A and C"; "B and C"; "A, B and C".