Push-push latch

Patent metadata

Field	Value
Publication number	US-9895969-B2
Application number	US-201414276390-A
Country	US
Kind code	B2
Filing date	May 13, 2014
Priority date	May 16, 2013
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

A push-push latch includes a slider slidably disposed on a frame. A resilient element is to urge the slider toward an extended state. The slider or the frame defines a cam-track. A pin member is connected to the frame or the slider. The pin member selectably engages a closed course in the cam-track to cause the slider to alternate between a retracted state and the extended state in response to alternating application and removal of an actuating force on the slider. An interference member is on the frame to selectively prevent the pin member from engaging the closed course thereby locking the slider in the retracted state. A pivotable catch is rotatably on the slider to open in the extended state and to close in the retracted state. A shape memory alloy actuator selectively causes the interference member to selectively prevent the pin member from engaging the closed course.

First claim

The invention claimed is:

1. A push-push latch, comprising:
a frame;
a slider slidably disposed on the frame;
a resilient element to urge the slider toward an extended state;
a cam-track defined by the slider or the frame;
a pin member connected to the frame or the slider, the pin member to selectably engage a closed course in the cam-track to cause the slider to alternate between a retracted state and the extended state in response to alternating application and removal of an actuating force on the slider;
an interference member disposed on the frame to selectively prevent the pin member from engaging a portion of the closed course thereby locking the slider in the retracted state;
a pivotable catch rotatably disposed on the slider to open in the extended state and to close in the retracted state; and
a shape memory alloy (SMA) actuator to selectively cause the interference member to selectively prevent the pin member from engaging the closed course.

2. The push-push latch as defined in claim 1 , further comprising an electrical connector in electrical contact with the SMA actuator to connect the SMA actuator to an actuating source of electrical energy.

3. The push-push latch as defined in claim 2 , further comprising:
a sensor to detect movement of the slider in response to the actuating force wherein the SMA actuator is connected to the actuating source of electrical energy in response to a detection of the movement of the slider in response to the actuating force.

4. The push-push latch as defined in claim 2 , further comprising:
a sensing element to detect a completion of actuation of the SMA actuator, wherein an electrical power supplied to the SMA actuator is reduced in response to the sensing element detecting the completion of actuation of the SMA actuator.

5. The push-push latch as defined in claim 1 wherein the pivotable catch is rotatably disposed on the slider to open and close in response to relative movement of the slider with respect to the frame wherein the pivotable catch is to selectively capture a flange-headed post fixedly attached to an object.

6. The push-push latch as defined in claim 5 wherein the frame is attached to a fuel filler housing and the flange-headed post is attached to a fuel filler door.

7. A push-push latch comprising:
a frame;
a slider slidably disposed on the frame;
a resilient element to urge the slider toward an extended state;
a cam-track defined by the slider or the frame;
a pin member connected to the frame or the slider, the pin member to selectably engage a closed course in the cam-track to cause the slider to alternate between a retracted state and the extended state in response to alternating application and removal of an actuating force on the slider;
an interference member disposed on the frame to selectively prevent the pin member from engaging a portion of the closed course thereby locking the slider in the retracted state;
a pivotable catch rotatably disposed on the slider to open in the extended state and to close in the retracted state;
a shape memory alloy (SMA) actuator to selectively cause the interference member to selectively prevent the pin member from engaging the closed course;
a cam spring having:
a first leg on a cam follower end of the cam spring;
an anchor end distal to the cam follower end;
a second leg on the anchor end; and
a resilient bridge connecting the first leg and the second leg wherein the first leg is the pin member and the second leg is attached to the frame;

an index lever projecting from the resilient bridge;
an actuator lever pivotably attached to the frame, the actuator lever in operable contact with the index lever wherein the actuator lever is the interference member; and
an extension spring connected to the actuator lever and to the frame to urge the actuator lever antagonistically to the resilient bridge via the index lever to extract the pin member from the closed course in the cam-track thereby locking the slider in the retracted state;
wherein the SMA actuator is connected to the actuator lever to contract in an actuated state to overcome the extension spring and allow the resilient bridge to cause the pin member to engage the closed course and wherein the extension spring is to cause the SMA actuator to stretch in an unactuated state.

8. The push-push latch as defined in claim 7 , further comprising:
an electrical connector in electrical contact with the SMA actuator to connect the SMA actuator to an actuating source of electrical energy;
a first electrical switch to close an electrical circuit to connect the SMA actuator to the actuating source of electrical energy in response to a detection of a movement of the slider in response to the actuating force; and
a second electrical switch to detect a completion of actuation of the SMA actuator wherein an electrical power supplied to the SMA actuator is reduced in response to the second electrical switch detecting the completion of actuation of the SMA actuator.

9. The push-push latch as defined in claim 7 wherein the pivotable catch is rotatably disposed on the slider to open and close in response to relative movement of the slider with respect to the frame wherein the pivotable catch is to selectively capture a flange-headed post fixedly attached to an object.

10. The push-push latch as defined in claim 9 wherein the frame is attached to a fuel filler housing, and the flange-headed post is attached to a fuel filler door.

11. A push-push latch comprising:
a frame;
a slider slidably disposed on the frame;
a resilient element to urge the slider toward an extended state;
a cam-track defined by the slider or the frame;
a pin member connected to the frame or the slider, the pin member to selectably engage a closed course in the cam-track to cause the slider to alternate between a retracted state and the extended state in response to alternating application and removal of an actuating force on the slider;
an interference member disposed on the frame to selectively prevent the pin member from engaging a portion of the closed course thereby locking the slider in the retracted state;
a pivotable catch rotatably disposed on the slider to open in the extended state and to close in the retracted state; and
a shape memory alloy (SMA) actuator to selectively cause the interference member to selectively prevent the pin member from engaging the closed course, wherein:
the slider is slidable along a longitudinal axis of the frame;
a shuttle slot is defined in the frame perpendicular to the longitudinal axis;
a shuttle is slidably disposed in the shuttle slot, the shuttle having the pin member extend from the shuttle into the cam-track;
a hinge knuckle is disposed on the frame at a hinge end of the frame;
a blocking pawl is pivotably disposed about a hinge pin;
the blocking pawl is the interference member;
the blocking pawl has a pawl end and a heel end on opposite sides of the hinge pin;
the hinge pin is disposed through the blocking pawl and the hinge knuckle;
a locking spring to urge the blocking pawl to a locked position in contact with the shuttle to selectively prevent the pin member from engaging the portion of the closed course thereby locking the slider in the retracted state;
an SMA wire is attached to the frame at a catch end distal to the hinge end;
the SMA wire is looped around the heel end of the blocking pawl;
the SMA wire is to produce a torque on the blocking pawl when the SMA wire is actuated;
the torque on the blocking pawl is antagonistic to the locking spring;
upon actuation of the SMA wire, the SMA wire is to overcome the locking spring and lift the pawl end to allow the shutt

Assignees

• Gm Global Tech Operations Llc

Inventors

• Alexander Paul W
• Culver Roger Herbert
• Dallos Jr Robert
• Zolno Aragorn
• Brown James Holbrook

Classifications

• B60K15/05 Primary

  Inlet covers · CPC title

• E05B83/34

  for fuel inlet covers essentially flush with the vehicle surface · CPC title

• E05B47/0009

  with thermo-electric actuators, e.g. heated bimetals · CPC title

• Y10T292/0945

  Operating means · CPC title

• E05C19/022

  Released by pushing in the closing direction · CPC title