1. A piezoelectric micro speaker comprising:
a device comprising:
a device plate comprising a front cavity therein,
a diaphragm disposed on a rear surface of the device plate overlapping the front cavity, and
a piezoelectric actuator disposed on a rear surface of the diaphragm;
a front plate disposed on a front surface of the device plate, the front plate comprising a radiation hole which communicates with the front cavity; and
a rear plate disposed on a rear surface of the device, the rear plate comprising a rear cavity formed in a front surface of the rear plate, and a vent portion which is a space which communicates with the rear cavity,
wherein the device plate further comprises at least one first vent hole which communicates with the vent portion, and the front plate further comprises at least one second vent hole which communicates with the at least one first vent hole.
2. The piezoelectric micro speaker of claim 1, wherein the at least one first vent hole is separated from the front cavity, and the at least one second vent hole is separated from the radiation hole.
3. The piezoelectric micro speaker of claim 1, wherein the rear plate has a substantially square outer circumference and the vent portion extends along a side of the rear plate.
4. The piezoelectric micro speaker of claim 3, wherein the piezoelectric actuator comprises a first electrode layer and a second electrode layer, and
wherein the rear plate further comprises:
a first via hole and a second via hole formed in opposite corners of the rear plate,
a first conductive plug disposed in the first via hole and connected to the first electrode layer of the piezoelectric actuator, and
a second conductive plug disposed in the second via hole and connected to the second electrode layer of the piezoelectric actuator.
5. The piezoelectric micro speaker of claim 3, wherein the at least one first vent hole is a slit extending along the side of the rear plate.
6. The piezoelectric micro speaker of claim 1, wherein the rear plate has a substantially square outer circumference, and the vent portion is formed on a corner of the rear plate.
7. The piezoelectric micro speaker of claim 6, wherein the piezoelectric actuator comprises a first electrode layer and a second electrode layer, and
wherein the rear plate further comprises:
a first via hole and a second via hole formed in opposite sides of the rear plate,
a first conductive plug disposed in the first via hole and connected to the first electrode layer of the piezoelectric actuator, and
a second conductive plug disposed in the second via hole and connected to the second electrode layer of the piezoelectric actuator.
8. A piezoelectric micro speaker comprising:
a device comprising:
a device plate comprising a front cavity therein,
a diaphragm disposed on a rear surface of the device plate overlapping the front cavity, and
a piezoelectric actuator disposed on a rear surface of the diaphragm;
a front plate disposed on a front surface of the device plate, the front plate comprising a radiation hole which communicates with the front cavity;
a rear plate disposed on a rear surface of the device, the rear plate comprising a rear cavity formed in a front surface of the rear plate; and
at least one vent hole which penetrates through a side surface of the micro speaker and which communicates with the rear cavity.
9. The piezoelectric micro speaker of claim 8, wherein the rear plate has a substantially square outer circumference, and the at least one vent hole comprises a hole along a side surface of the rear plate, wherein a lower surface of the device forms an upper wall of the vent hole.
10. The piezoelectric micro speaker of claim 8, wherein the piezoelectric actuator comprises a first electrode layer and a second electrode layer, and
wherein the rear plate further comprises:
a first via hole and a second via hole formed therethrough in opposite corners of the rear plate,
a first conductive plug disposed in the first via hole and connected to a first electrode of layer of the piezoelectric actuator, and
a second conductive plug disposed in the second via hole and connected to a second electrode layer of the piezoelectric actuator.
11. The piezoelectric micro speaker of claim 8, wherein the rear plate has a substantially square outer circumference, and the at lease one vent hole is a hole through a side surface of the rear plate.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An image reading apparatus, comprising:
a body including,
an exposure glass,
a reader configured to read an image of an original sheet through the exposure glass, and
a guide disposed on the exposure glass and configured to support the original sheet, the guide including first and second positioners disposed in upstream and downstream ends of a sheet conveyance direction; and
an auto document feeder configured to be swingably moved between an open position and a closed position relative to the body and to feed the original sheet onto the exposure glass when situated at the closed position, the auto document feeder including,
a press configured to press the original sheet onto the exposure glass, and
a regulator mounted to the press and including first and second slanted portions respectively, and configured to contact the respective first and second positioners of the guide at the first and second slanted ends in the upstream and downstream ends of the sheet conveyance direction when the auto document feeder is situated at the closed position so as to form a slit between the exposure glass and the press, the slit allowing the original sheet to pass therethrough.
2. The image reading apparatus according to claim 1, wherein the regulator regulates a clearance between the press and the exposure glass when the auto document feeder is situated at the closed position.
3. The image reading apparatus according to claim 1,
wherein the positioners have a shape corresponding to a shape of the regulator and configured to contact the regulator.
4. The image reading apparatus according to claim 1, wherein the regulator has a symmetrical shape in upstream and downstream sides in a conveyance direction of the original sheet.
5. The image reading apparatus according to claim 1, wherein each of the slanted portions contacts an apex of the positioner.
6. The image reading apparatus according to claim 1, further comprising:
a pressing member configured to apply a pressure downward to the press.
7. The image reading apparatus according to claim 1, wherein the guide includes a fixing member configured to fix the exposure glass to the body.
8. The image reading apparatus according to claim 1, wherein the regulator is integrally molded with the press.
9. The image reading apparatus according to claim 1, wherein the regulator is separately molded from the press.
10. The image reading apparatus according to claim 9, wherein the regulator is jointed with the press by caulking.
11. The image reading apparatus according to claim 6, wherein the pressing member includes a spring.
12. An image reading apparatus, comprising:
a body including,
an exposure glass,
a reader configured to read an image of an original sheet through the exposure glass, and
means for guiding disposed on the exposure glass and for supporting the original sheet, and including a first and second means for positioning disposed in upstream and downstream ends of a sheet conveyance direction; and
an auto document feeder configured to be swingably moved between an open position and a closed position relative to the body and to feed the original sheet onto the exposure glass when situated at the closed position, the auto document feeder including,
means for pressing the original sheet onto the exposure glass, and
means for contacting the means for guiding, including first and second slanted portions respectively disposed in upstream and downstream ends of a sheet conveyance direction, to contact the first and second means for positioning at both of the first and second slanted portions in the upstream and downstream ends of the sheet conveyance direction when the auto document feeder is situated at the closed position so as to form a slit between the exposure glass and the means for pressing, the slit allowing the original sheet to pass therethrough, the means for contacting being mounted to the means for pressing.
13. The image reading apparatus according to claim 12, further comprising:
means for applying a pressure downward to the means for pressing.