US 7,119,552 B2 · Capacitance type force sensors

Abstract

Capacitance element electrodes (E1 to E5) and a grounded reference electrode (E0) are formed on a substrate (20). A displacement electrode (40) that is Z-axially displaced in accordance with a Z-axial movement of a detective member (30) externally operated, is disposed so as to be opposed to the above electrodes (E0 to E5). The displacement electrode (40) cooperates with the reference electrode (E0) and the capacitance element electrodes (E1 to E5) to form capacitance elements (C0 to C5), respectively. Each of the capacitance elements (C1 to C5) is connected to the capacitance element (C0) in series in relation to an externally input signal. Changes in the capacitance values of the capacitance elements (C1 to C5) when the detective member (30) is moved, is detected by a signal processing circuit having hysteretic characteristics. Thereby, the displacement of the detective member (30) is detected.

Drawings

Claims21

Dependent claims

A capacitance type sensor comprising:

a substrate that provides an XY plane of an XYZ three-dimensional coordinate system;
a detective member being opposed to the substrate;
a conductive member disposed between the substrate and the detective member so as to be Z-axially displaceable in accordance with Z-axial displacement of the detective member;
a capacitance element electrode formed on the substrate to cooperate with the conductive member to form a first capacitance element;
and
a reference electrode formed on the substrate to cooperate with the conductive member to form a second capacitance element, and kept at a ground potential or another fixed potential,
wherein the first and second capacitance elements are connected in series in relation to a signal input to the capacitance element electrode, and displacement of the detective member can be detected on the basis of detection of a change in the capacitance value of the first capacitance element caused by a change in the interval between the conductive member and the capacitance element electrode;
and
wherein the capacitance type sensor comprises two capacitance element electrodes in a pair, and after each of analog signals corresponding to signals respectively input to a circuit including one of the capacitance element electrodes and a circuit including the other of the capacitance element electrodes, has passed the respective signal processing circuit having hysteretic characteristics and the analog signals are input to a logic element, an output signal is output from the logic element.

6 more elements

A capacitance type sensor comprising:

a substrate that provides an XY plane of an XYZ three-dimensional coordinate system;
a detective member being opposed to the substrate;
a conductive member disposed between the substrate and the detective member so as to be Z-axially displaceable in accordance with Z-axial displacement of the detective member;
a capacitance element electrode formed on the substrate to cooperate with the conductive member to form a first capacitance element;
and
a reference electrode formed on the substrate to cooperate with the conductive member to form a second capacitance element, and kept at a ground potential or another fixed potential;
wherein the first and second capacitance elements are connected in series in relation to a signal input to the capacitance element electrode, and displacement of the detective member can be detected on the basis of detection of a change in the capacitance value of the first capacitance element caused by a change in the interval between the conductive member and the capacitance element electrode;
and
wherein the sensor comprises two capacitance element electrodes in a pair, and each of analog signals corresponding to signals respectively input to a circuit including one of the capacitance element electrodes and a circuit including the other of the capacitance element electrodes is input to a Schmitt trigger type logic element having Schmitt trigger input characteristics and an output signal is output from the Schmitt trigger type logic element.

6 more elements

Dependencies are inferred from the claim text.

Description14,107 words

Summary1,726 words

#The present invention relates to a capacitance type sensor suitably used for inputting operations in multidimensional directions.

#A capacitance type sensor is used as a device for converting the intensity and direction of a force applied by an operator, into an electric signal. For example, as an input device for a game machine used is a device incorporated as a capacitance type force sensor, so-called joy stick, for inputting operations in multidimensional directions.

#Using the capacitance type sensor, an operation quantity with a predetermined dynamic range can be input as the intensity of a force applied by the operator. Such a sensor may be used in the form of a two-dimensional or three-dimensional force sensor capable of detecting each directional component divided from the applied force. In particular, a capacitance type force sensor in which a capacitance element is made up of two electrodes and a force is detected on the basis of a change in the capacitance value due to a change in the interval between the electrodes, has a merit that a cost reduction can be intended by simplifying the construction. Therefore, sensors of this type have been put in practical use in various fields.

Brief description of the drawings22 figures

#FIG. 1 is a schematic sectional view of a capacitance type sensor according to an embodiment of the present invention;

#FIG. 2 is an upper view of a detective member of the capacitance type sensor of FIG. 1;

#FIG. 3 is a view showing an arrangement of a plurality of electrodes formed on a substrate of the capacitance type sensor of FIG. 1;

Detailed description11,832 words

#Hereinafter, a preferred embodiment of the present invention will be described with reference to drawings. In the embodiment as will be described below, a capacitance type sensor of the present invention is used as a force sensor.

#FIG. 1 is a schematic sectional view of a capacitance type sensor according to an embodiment of the present invention. FIG. 2 is an upper view of a detective member of the capacitance type sensor of FIG. 1. FIG. 3 is a view showing an arrangement of a plurality of electrodes formed on a substrate of the capacitance type sensor of FIG. 1.

#The capacitance type sensor 10 includes a substrate 20; a detective member 30 as an operation member to which a force is externally applied by operation by a human or the like; a displacement electrode 40; capacitance element electrodes E1 to E5 and a reference electrode E0 as a common electrode, formed on the substrate 20; an insulating film 50 formed in close contact with the capacitance element electrodes E1 to E5 and the reference electrode E0 to cover the corresponding part of the upper surface of the substrate 20; and a supporting member 60 for supporting and fixing the detective member 30 and the displacement electrode 40 to the substrate 20.

Facts

Application

10/541,424Filed 6 Jan 2003

Published

US 2006/0049836 A19 Mar 2006

Granted

10 Oct 2006

Term ended

6 Jan 2023

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification5 codes

G06F 3/0338
Pointing devices displaced or positioned by the user , e.g. mice, trackballs, pens or joysticks; Accessories therefor: with detection of limited…
G01L 1/144
Using capacitors: with associated circuitry
G01L 5/165
For measuring several components of force: using variations in capacitance
G06F
Computing and data processing

Capacitance type force sensors

Life of this patent

Capacitance type force sensors

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims21

Description14,107 words

Drawings

Classification5 codes

Life of this patent

Description14,107 words