Piezo-electric type of pressure sensor and pressure-detecting device employing the same

Claim 2

A piezo-electric type of pressure distribution detecting device comprising a piezo-electric type of pressure sensor, said piezo-electric type of pressure sensor comprising: a plurality of piezo-electric elements arranged in a first direction and a second direction intersecting therewith for outputting voltages corresponding to pressure changes; switching means provided in each piezo-electric element and connected to said piezo-electric element, said switching means assuming a conductive state or a non-conductive state, a plurality of control lines extending in said first direction for causing switching means of each piezo-electric element arranged in the first direction to be conductive or non-conductive; a plurality of reading lines extending in said second direction and connected to said switching means of each piezo-electric element arranged in the second direction for reading a charge from a piezo-electric element through a switching means that is rendered conductive through a control line; selecting means for selecting one of said plurality of control lines to select a piezo-electric element whose output voltage is to be read among a plurality of columns of piezo-electric sensor elements arranged in the first direction; and accumulating means for accumulating a pressure value based on an output voltage read through a reading line from a piezo-electric element selected by means of said selecting means.

Claim 3

A piezo-electric type of pressure sensor according to claim 1, wherein said piezo-electric element is formed of a piezo-electric ceramic material having rigidity.

Claim 4

A piezo-electric type of pressure sensor according to claim 1, wherein said piezo-electric element is formed of a piezo-electric monocrystal material having rigidity.

Claim 5

A piezo-electric type of pressure sensor, comprising: a plurality of piezo-electric sensor elements arranged in a first direction and a second direction intersecting therewith; each piezo-electric sensor element comprising a piezo-electric element which generates a charge corresponding to an external pressure applied to said piezo-electric element; switching means connected to each said piezo-electric element, said switching means assuming a conductive state or a non-conductive state; a plurality of control lines corresponding to said first direction for causing said switching means of respective groups of said piezo-electric sensor elements arranged in the first direction to be conductive or non-conductive; and a plurality of reading lines corresponding to said second direction and connected to said switching means of respective groups of said piezo-electric sensor elements arranged in the second direction for reading external pressures applied to said piezo-electric elements as a function of charges generated by said piezo-electric elements, in response to said external pressures, through switching means rendered conductive by said control lines.

Claim 6

A piezo-electric type of pressure sensor, comprising: a plurality of piezo-electric sensor elements arranged in a first direction and a second direction intersecting therewith; each piezo-electric sensor element comprising a piezo-electric element which generates a charge corresponding to an external pressure applied to said piezo-electric element; switching means connected to each said piezo-electric element, said switching means assuming a conductive state or a non-conductive state; a plurality of control lines corresponding to said first direction for causing said switching means of respective groups of said piezo-electric sensor elements arranged in the first direction to be conductive or non-conductive; and a plurality of reading lines corresponding to said second direction and connected to said switching means of respective groups of said piezo-electric sensor elements arranged in the second direction for reading external pressures applied to said piezo-electric elements as a function of charges generated by said piezo-electric elements, in response to said external pressures, through switching means rendered conductive by said control lines.

Claim 7

A piezo-electric pressure distribution detecting device comprising: a plurality of piezo-electric elements arranged in an array which extends in a first direction and a second direction, wherein each said piezo-electric element generates a respective voltage in response to pressure applied to said piezo-electric element; a respective switching means connected to each said piezo-electric element for receiving said voltage generated thereby, each said switching means having a conductive state and a non-conductive state; a plurality of control lines, each said control line being connected to said switching means of a respective group of said piezo-electric elements arranged in said first direction, for controlling said switching means to be in said conductive or non-conductive state; a plurality of reading lines, each said reading line being connected to the switching means of a respective group of said piezo-electric elements arranged in said second direction, for reading said voltage generated by said piezo-electric elements when said switching means of said respective elements are in their conductive state; selecting means for selecting a group of said piezo-electric elements arranged in said first direction from which an output voltage is to be read, by selecting the respective control line of said group of piezo-electric elements; and accumulating means for receiving an output voltage from said selected group of piezo-electric elements through one of said reading lines, and accumulating said output voltage to indicate a detected value of said pressure applied to said piezo-electric pressure distribution detecting device.

Claim 8

A piezo-electric pressure distribution detecting device comprising: a plurality of piezo-electric elements arranged in an array which extends in a first direction and a second direction, wherein each said piezo-electric element generates a respective voltage in response to pressure applied to said piezo-electric element; a respective switching means connected to each said piezo-electric element for receiving said voltage generated thereby, each said switching means having a conductive state and a non-conductive state; a plurality of control lines, each said control line being connected to said switching means of a respective group of said piezo-electric elements arranged in said first direction, for controlling said switching means to be in said conductive or non-conductive state; a plurality of reading lines, each said reading line being connected to the switching means of a respective group of said piezo-electric elements arranged in said second direction, for reading said voltage generated by said piezo-electric elements when said switching means of said respective elements are in their conductive state; selecting means for selecting a group of said piezo-electric elements arranged in said first direction from which an output voltage is to be read, by selecting the respective control line of said group of piezo-electric elements; and accumulating means for receiving an output voltage from said selected group of piezo-electric elements through one of said reading lines, and accumulating said output voltage to indicate a detected value of said pressure applied to said piezo-electric pressure distribution detecting device.

Claim 9

A detecting device as in claim 5, wherein said selecting means also selects one of said reading lines so as to select said piezo-electric element from which said output voltage is to be received by said accumulating means.

Claim 10

A detecting device as in claim 6, further comprising processing means for processing said detected pressure value accumulated by said accumulating means.

Claim 11

A detecting device as in claim 7, further comprising matrix control means for controlling said selecting means and said processing means for detecting and processing said pressure values in a predetermined manner.

Claim 12

A detecting device as in claim 8, wherein said matrix control means causes said pressure values from all of said piezo-electric elements to be detected and processed continuously in a predetermined sequence.

Claim 13

A detecting device as in claim 8, wherein said processing means includes a peak-hold circuit which receives an output of said accumulating means.

Claim 14

A detecting device as in claim 10, wherein said matrix control means issues a reset signal to said peak-hold circuit with a predetermined timing.

Claim 15

A detecting device as in claim 10, wherein said processing means further includes a data processor which receives an output of said peak-hold circuit.

Claim 16

A detecting device as in claim 12, wherein said matrix control means issues an element-switching information signal to said data processor to indicate which piezo-electric element has been read to generate a detected pressure value.

Claim 17

A piezo-electric pressure distribution detecting device comprising: a plurality of piezo-electric elements arranged in an array which extends in a first direction and a second direction, wherein each said piezo-electric element generates a respective voltage in response to pressure applied to said piezo-electric element; a respective switching means connected to each said piezo-electric element for receiving said voltage generated thereby, each said switching means having a conductive state and a non-conductive state; a plurality of control lines, each said control line being connected to said switching means of a respective group of said piezo-electric elements arranged in said first direction, for controlling said switching means to be in said conductive or non-conductive state; a plurality of reading lines, each said reading line being connected to the switching means of a respective group of said piezo-electric elements arranged in said second direction, for reading said voltage generated by said piezo-electric elements when said switching means of said respective elements are in their conductive state; selecting means for selecting a group of said piezo-electric elements arranged in said first direction from which an output voltage is to be read, by selecting the respective control line of said group of piezo-electric elements; and storage means connected to said selected group of piezo-electric elements for storing said output voltage generated by said selected group of piezo-electric elements.

Claim 18

A piezo-electric pressure distribution detecting device comprising: a plurality of piezo-electric elements arranged in an array which extends in a first direction and a second direction, wherein each said piezo-electric element generates a respective voltage in response to pressure applied to said piezo-electric element; a respective switching means connected to each said piezo-electric element for receiving said voltage generated thereby, each said switching means having a conductive state and a non-conductive state; a plurality of control lines, each said control line being connected to said switching means of a respective group of said piezo-electric elements arranged in said first direction, for controlling said switching means to be in said conductive or non-conductive state; a plurality of reading lines, each said reading line being connected to the switching means of a respective group of said piezo-electric elements arranged in said second direction, for reading said voltage generated by said piezo-electric elements when said switching means of said respective elements are in their conductive state; selecting means for selecting a group of said piezo-electric elements arranged in said first direction from which an output voltage is to be read, by selecting the respective control line of said group of piezo-electric elements; and storage means connected to said selected group of piezo-electric elements for storing said output voltage generated by said selected group of piezo-electric elements.

Claim 19

A detecting device as in claim 14, wherein said storage means comprises a capacitance connected across each said piezoelectric element for storing said respective output voltage generated thereby.

Claim 20

A detecting device as in claim 14, wherein said storage means comprises accumulating means for receiving an output voltage from said selected group of piezo-electric elements through one of said reading lines, and accumulating said output voltage to indicate a detected value of said pressure applied to said piezo-electric pressure distribution detecting device.

Claim 21

A piezo-electric pressure distribution detecting device comprising: a plurality of piezo-electric elements arranged in an array which extends in a first direction and a second direction, wherein each said piezo-electric element generates a respective voltage in response to pressure applied to said piezo-electric element; a respective switching means connected to each said piezo-electric element for receiving said voltage generated thereby, each said switching means having a conductive state and a non-conductive state; a plurality of control lines, each said control line being connected to said switching means of a respective group of said piezo-electric elements arranged in said first direction for controlling said switching means to be in said conductive or non-conductive state; a plurality of reading lines, each said reading line being connected to the switching means of a respective group of said piezo-electric elements arranged in said second direction, for reading said voltage generated by said piezo-electric elements when said switching means of said respective elements are in their conductive state; and a capacitance connected across each said piezoelectric element for storing said respective voltage generated thereby.

Claim 22

A piezo-electric pressure distribution detecting device comprising: a plurality of piezo-electric elements arranged in an array which extends in a first direction and a second direction, wherein each said piezo-electric element generates a respective voltage in response to pressure applied to said piezo-electric element; a respective switching means connected to each said piezo-electric element for receiving said voltage generated thereby, each said switching means having a conductive state and a non-conductive state; a plurality of control lines, each said control line being connected to said switching means of a respective group of said piezo-electric elements arranged in said first direction for controlling said switching means to be in said conductive or non-conductive state; a plurality of reading lines, each said reading line being connected to the switching means of a respective group of said piezo-electric elements arranged in said second direction, for reading said voltage generated by said piezo-electric elements when said switching means of said respective elements are in their conductive state; and a capacitance connected across each said piezoelectric element for storing said respective voltage generated thereby.