Apparatus including two housings and a piezoelectric transducer

1. An apparatus comprising:

a first housing;

a hinge coupled to the first housing;

a second housing coupled the first housing via the hinge, wherein the first housing has a closed position when the first housing is substantially adjacent to the second housing and the first housing has an open position when a portion of the first housing is substantially away from the second housing;

a first piezoelectric element coupled to the second housing, wherein the first piezoelectric element is substantially in contact with the first housing when the first housing is in the closed position;

a user interface coupled to the second housing; and

a controller coupled to the first piezoelectric element and the user interface, the controller configured to drive the first piezoelectric element to cause the first housing to vibrate against the second housing when the first housing is in the closed position and the controller configured to drive the first piezoelectric element to provide tactile feedback in response to user activation of the user interface.

2. The apparatus according to claim 1 , wherein the controller detects user input by detecting a change in oscillations of the first piezoelectric element in response to a user squeezing the first housing against the second housing, and

wherein the controller is configured to adjust a signal that drives the first piezoelectric element in response to the user input.

3. The apparatus according to claim 1 , further comprising an accelerometer coupled to the controller, the accelerometer configured to detect a change in vibration as the result of user input.

4. The apparatus according to claim 1 , further comprising an accelerometer coupled to the controller, wherein the accelerometer detects a magnitude of vibration or frequency of vibration of the first housing against the second housing, wherein the controller adjusts a parameter of operation of the apparatus based on the detected magnitude of vibration or frequency of vibration.

5. The apparatus according to claim 1 , further comprising an accelerometer coupled to the controller, wherein the accelerometer detects an open or closed position of the first housing relative to the second housing based on whether the first housing vibrates with respect to the second housing when the controller drives the piezoelectric element.

6. The apparatus according to claim 1 , further comprising a second piezoelectric element coupled to the second housing and coupled to the controller, wherein the second piezoelectric element operates in conjunction with the first piezoelectric element to cause the first housing to vibrate when the first housing is in the closed position.

7. The apparatus according to claim 6 , wherein the second housing includes a length extending from the hinge, wherein the first piezoelectric element is located along the length at a distance from the hinge different from a distance from the hinge of the second piezoelectric element along the length.

8. The apparatus according to claim 7 , wherein the controller is configured to drive the first piezoelectric element with a signal that is out of phase with a signal that drives the second piezoelectric element, and

wherein the controller is configured to drive the first piezoelectric element with a signal that is in phase with a signal that drives the second piezoelectric element if an in phase signal is adequate for vibration.

9. The apparatus according to claim 1 , wherein the controller is configured to drive the first piezoelectric element with a first waveform that causes the first housing to vibrate against the second housing when the first housing is in the closed position and wherein the controller is configured to drive the first piezoelectric element with a second waveform that produces a louder audible signal than the first waveform.

10. The apparatus according to claim 1 ,

wherein the first piezoelectric element breaks contact with the first housing when the first housing is in the open position, and

wherein the first piezoelectric element does not cause the first housing to vibrate against the second housing when the first housing is in the open position when the controller drives the first piezoelectric element.

11. An apparatus comprising:

a first housing;

a speaker coupled to the first housing;

a hinge coupled to the first housing, the hinge including a cam mechanism;

a second housing coupled the first housing via the hinge, wherein the first housing has a closed position when the first housing is substantially adjacent to the second housing and the first housing has an open position when a portion of the first housing is substantially away from the second housing;

a microphone coupled to the second housing;

a first piezoelectric element coupled to the second housing, wherein the first piezoelectric element is substantially in contact with the first housing when the first housing is in the closed position;

a user interface coupled to the second housing; and

a controller coupled to the first piezoelectric element and the user interface, the controller configured to drive the piezoelectric element to cause the first housing to vibrate against the second housing when the first housing is in the closed position and the controller is configured to drive the piezoelectric element to provide tactile feedback in response to user activation of the user interface.

12. The apparatus according to claim 11 , wherein the controller is configured to drive the first piezoelectric element with a first waveform that causes the first housing to vibrate against the second housing when the first housing is in the closed position and wherein the controller is configured to drive the first piezoelectric element with a second waveform that has a longer waveform that produces a louder audible signal than the first waveform.

13. The apparatus according to claim 11 , further comprising;

a first post coupled to the first housing and the first piezoelectric element when the first housing is in the closed position;

a second piezoelectric element coupled to the second housing; and

a second post coupled to the first housing and the second piezoelectric element when the first housing is in the closed position, wherein the controller drives the second piezoelectric element in conjunction with the first piezoelectric element to cause the first housing to vibrate when the first housing is in the closed position.

14. The apparatus according to claim 11 , wherein the controller is configured to detect a user input by detecting a dampening of oscillations of the first piezoelectric element in response to a user squeezing the first housing against the second housing.

15. The apparatus according to claim 14 , wherein the controller is configured to change an alert mode by determining the dampened oscillations are the result of a user squeezing the first housing against the second housing.

16. The apparatus according to claim 11 , further comprising an accelerometer coupled to the controller, wherein the accelerometer detects a magnitude of vibration or frequency of vibration of the first housing against the second housing, wherein the controller adjusts a parameter of operation of the apparatus based on the detected magnitude of vibration or frequency of vibration.

17. The apparatus according to claim 16 , wherein the parameter of operation comprises an amplitude or a frequency of a signal driving the first piezoelectric element, wherein the controller increases an amplitude or adjusts a frequency of the signal driving the first piezoelectric element if the magnitude of vibration or the frequency of vibration is below a threshold.

18. The apparatus according to claim 16 , wherein the parameter of operation comprises an alert mode, wherein the controller switches an alert mode to an audible alert mode if the magnitude of vibration is above a threshold.

19. The apparatus according to claim 16 , wherein the controller is further configured to measure an amplitude of vibration or frequency of vibration and adjust a frequency of a signal driving the first piezoelectric element to increase the amplitude of vibration.

20. An apparatus comprising:

a first housing;

a hinge coupled to the first housing;

a second housing coupled the first housing via the hinge, wherein the first housing has a closed position when the first housing is substantially adjacent to the second housing and the first housing has an open position when a portion of the first housing is substantially away from the second housing;

a first piezoelectric element coupled to the second housing, wherein the first piezoelectric element is substantially in contact with the first housing when the first housing is in the closed position;

a second piezoelectric element coupled to the second housing;

a user interface coupled to the second housing; and

a controller coupled to the first piezoelectric element and the user interface, the controller configured to drive the first piezoelectric element to cause the first housing to vibrate against the second housing when the first housing is in the closed position, the controller configured to drive the second piezoelectric element in conjunction with the first piezoelectric element to cause the first housing to vibrate when the first housing is in the closed position, and the controller configured to drive the first piezoelectric element to provide tactile feedback in response to user activation of the user interface.