FIELD OF THE INVENTION
[0001] The present invention relates to a position input device such as pointing device
used in personal computer, word processor, other information processing apparatus,
and home-use game appliances, and an input apparatus using the same.
BACKGROUND OF THE INVENTION
[0002] A prior art is described by reference to a pointing device using a strain gauge shown
in Fig. 17 (a), (b), and (c). As shown in the diagram, on four sides of a bar-shaped
stick 23, strain gauges 24a, 24b in the X-axis direction, and 25a, 25b in the Y-axis
direction are adhered.
[0003] The four strain gauges 24a, 24b, 25a, and 25b are connected as shown in Fig. 17 (c),
that is, the strain gauges 24a, 24b in the X-axis direction being in series, and the
strain gauges 25a, 25b in the Y-axis direction being in series.
[0004] The operation of the pointing device is described below. The force applied in the
stick 23 distorts the stick 23 in the X-axis and Y-axis, and the strain gauges 24a,
24b, 25a, and 25b measure voltages Vx, Vy of which resistance is changed by the distortion
of the stick 23, and therefore the direction of the applied force is detected by the
synthesis of the changing amounts of the X-axis and Y-axis, and the magnitude of the
applied force, by the absolute value of the changing amounts of the X-axis and Y-axis.
[0005] However, in such conventional constitution, since strain gauges are used, it is expensive.
Other problems were the poor operation feeling such as difficulty in recognizing the
feeling in actual manipulation, and the difficulty in making compact.
SUMMARY OF THE INVENTION
[0006] It is hence a primary object of the invention to present a compact position input
device capable of detecting the direction of force and magnitude of force, being inexpensive
and excellent in controllability, and an input apparatus using the same.
[0007] The invention provides a position input device comprising a lower film disposing
independent electrodes in four directions individually, an upper film disposing common
electrode confronting the independent electrodes, pressure sensitive elements disposed
between the independent electrodes and common electrodes respectively, a pressing
plate possessing protrusions at the positions for pressing the pressure sensitive
elements corresponding to the independent electrodes and common electrode, and an
operation lever for manipulating the pressing plate.
[0008] In the position input device of the invention, a printed wiring board is used instead
of the lower film.
[0009] In the position input device of the invention, the pressing plate and the operation
lever are constituted in one body.
[0010] In the position input device of the invention, a spacer is placed between the pressure
sensitive elements so that the pressure sensitive elements may not be pressed except
in operation time.
[0011] In the position input device of the invention, pressure sensitive rubber is used
as pressure sensitive elements.
[0012] In the position input device of the invention, pressure sensitive rubber is used
as pressure sensitive elements, and the individual pressure sensitive elements are
constituted into one body with the connecting parts.
[0013] The invention also provides a position input device comprising an A/D converter connected
to the independent electrodes, and an operating unit connecting a memory unit in which
the procedure for processing the digital data obtained by the A/D converter is written,
wherein the memory unit possesses a table for converting the digital data obtained
by the A/D converter into an operating force of the operation lever or a moving speed
corresponding to the operating force of the operation level.
[0014] The invention also relates to an input apparatus using a position input device possessing
plural input keys, and an operation lever set at a same height of the input keys or
slightly higher, adjacently to the input keys.
[0015] An outline of the operation of the invention is described below.
[0016] When the force applied to the operation lever in the constitution described above
is applied to the pressure sensitive elements in four directions through protrusions
of the pressing plate, the changing resistances produced in the pressure sensitive
elements are read from lead wires of the in dependent electrodes and the common electrode,
and the pressure sensitive elements are sandwiched between the upper and lower films,
and therefore the structure is thin, it is easy to manufacture, and it is possible
to produce at low cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Fig. 1 is a drawing showing an embodiment of a position input device of the invention.
[0018] Fig. 2 is a drawing showing pressing plate which is an essential part of the position
input device of the invention.
[0019] Fig. 3 (a) is a plan view of the position input device of the invention, and Fig.
3 (b) is its cross sectional view.
[0020] Fig. 4 is a diagram showing an equivalent circuit of the position input device of
the invention.
[0021] Fig. 5 is a diagram showing the relation between the pressure and resistance of the
pressure sensitive rubber of the position input device of the invention.
[0022] Fig. 6 is a diagram explaining the table for converting the digital data obtained
by the A/D converter of the position input device of the invention into the manipulated
force of the operation lever.
[0023] Fig. 7 is a diagram showing the changes of resistance in the thickness direction
of the pressure sensitive rubber of the position input device of the invention by
the force in the thickness direction, and changes of the voltage for A/D conversion.
[0024] Fig. 8 is a diagram explaining the behavior of changes of the resistance in the thickness
direction of the pressure sensitive rubber of the position input device of the invention
by the force in the thickness direction.
[0025] Fig. 9 (a) is a diagram explaining the operation of the position input device of
the invention, and Fig. 9 (b) is its side view.
[0026] Fig. 10 (a) is a plan view explaining the operation of the position input device
in other embodiment of the invention, and Fig. 10 (b) is its side view.
[0027] Fig. 11 is a diagram of a position input device in a different embodiment of the
invention.
[0028] Fig. 12 is a diagram showing the pressure sensitive rubber which is an essential
part of the position input device in a further different embodiment of the invention.
[0029] Fig. 13 (a) is a diagram showing an input apparatus of the invention possessing plural
keys using a position input device herein, and Fig. 13 (b) is its side view.
[0030] Fig. 14 is a diagram showing the relation between a film disposing common electrode
and a film disposing independent electrodes which are essential parts of a position
input device in another embodiment of the invention.
[0031] Fig. 15 is a diagram showing the relation between a film disposing common electrode
and a film disposing independent electrodes which are essential parts of a position
input device in another different embodiment of the invention.
[0032] Fig. 16 is a diagram showing the relation between a film disposing common electrode
and a film disposing independent electrodes which are essential parts of a position
input device in a further different embodiment of the invention.
[0033] Fig. 17 (a) is a diagram showing strain gauges which are essential parts of the pointing
device of a conventional position input device, Fig. 17 (b) is its side view, and
Fig. 17 (c) is its equivalent circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] As shown in Fig. 1, on the upper surface of a lower film 9 having a hole 9a provided
in the center, four independent electrodes 1, 2, 3 and 4 disposed in four directions
are formed, and from the four independent electrodes 1, 2, 3 and 4, individual lead
wires 5, 6, 7 and 8 are drawn out respectively and wired on the lower film 9. Similarly,
on an upper film 12 having a hole 12a provided in the center, common electrode 10
and common lead wire 11 corresponding to all of the four independent electrodes 1,
2, 3 and 4 formed on the lower film 9 are wired.
[0035] Between the lower film 9 and upper film 12, four pressure sensitive elements 13a,
13b, 13c and 13d made of pressure sensitive rubber of which resistance changes depending
on the pressure in the thickness direction are held to compose contact points, in
contact with the four independent electrodes 1, 2, 3 and 4 on the lower film 9, and
also in contact with the common electrode 10 provided beneath the upper film 12.
[0036] In the upper part of the upper film 12, a pressing plate 14 is disposed, and in the
lower part thereof, as shown in Fig. 2, four spherical protrusions 14a for pressing
the pressure sensitive elements 13a, 13b, 13c and 13d, respectively, are disposed,
together with two stopping parts 14b provided on the circumference of the opposite
side of the plane having a shaft 14c formed in the center, and a protrusions 14a.
As shown n Fig. 1, an operation lever 15 and an upper case 16 are disposed on the
upper surface of the pressing plate 14, and the assembly constitution is as shown
in Fig. 3 (a), (b), in which the shaft portion of the operation lever 15 is inserted
into a shaft hole 16a of the upper case 16 from the opening side of the upper case
16, and the pressing plate 14 is combined with the upper case 16 so as to pinch the
operation lever 15, and the stopping parts 14b of the pressing pat 14 are inserted
and stopped into pressing plate stopping holes 16b provided in the upper case 16.
[0037] The shaft 14c provided in the center of the lower side of the pressing plate 14 is
combined with the hole 12a in the central part of the upper film 12 for composing
the contact parts and the hole 9a in the central part of the lower film 9, is further
assembled with the hole 17a in the central part of the lower case 17 to formed into
one body, and screws 18 is driven into screw holes 17b provided at four corners of
the lower case 17 to fasten the upper case 16 by screwing.
[0038] In this constitution of the invention, meanwhile, the pressure sensitive elements
13a, 13b, 13c, and 13d can be printed on the four independent electrodes 1, 2, 3 and
4 by using pressure sensitive conductive ink, or on the common electrodes 10. In this
constitution, the invention is capable of detecting the changes of the resistance
of the individual pressure sensitive elements 13a, 13b, 13c and 13d, by measuring
the resistance between the common lead wire 11 and the individual lead wire 5, 6,
7 or 8.
[0039] Fig. 5 is a characteristic diagram showing the changes of the resistance of the individual
pressure sensitive element 13a, 13b, 13c or 13d in the thickness direction, in which
the pressing force can be known by measuring the resistance of the pressure sensitive
element 13a, 13b, 13c or 13d, for example, the pressing force is 200 g if the resistance
of the pressure sensitive element 13a, 13b, 13c or 13d in the thickness direction
is 10 kΩ, or the pressing force is 400 g if the resistance is 5.9 kΩ. That is, by
measuring the resistance, the pressing force can be recognized.
[0040] Incidentally, as shown in Fig. 4, the position input device of the invention incorporates
an A/D converter, and also possesses a one-chip microcomputer in which the procedure
for processing the digital data obtained by the A/D converter is written into a memory
unit (ROM), and this microcomputer possesses, as shown in Fig. 6, a table for converting
the digital data obtained by the A/D converter into the operating force received by
the operation lever or the moving speed corresponding to this operating force.
[0041] Fig. 7 shows a characteristic diagram showing the changes of the resistance of the
pressure sensitive element 13a, 13b, 13c or 13d in the thickness direction by the
force in the thickness direction, and changes of the voltage for A/D conversion, and
the A/D converted value as shown in Fig. 7 is obtained by A/D conversion. By converting
it into the operating force as shown in Fig. 6 by using the table, the pressing force
is known.
[0042] The operation of the position input device of the embodiment having such constitution
is explained below by reference to Fig. 8.
[0043] When the operation lever 15 is pressed with a force F, forces Fa, Fb, Fc and Fd corresponding
to the pushing positions are applied to the spherical protrusions 14a provided at
four positions of the pressing plate 14. In particular, a downward force is applied
to the pressure sensitive elements 13a, 13b, so that the resistance value decreases
according to the characteristic diagram in Fig. 5.
[0044] That is, by measuring the resistance of the four pressure sensitive elements 13a,
13b, 13c, and 13d, the "direction" and "magnitude of force" showing what force is
applied in which direction can be known.
[0045] Besides, as shown in Fig. 9 (a), (b), since the operation lever 15 and pressing plate
14 are composed of different parts, when the operation lever 15 is manipulated by
applying a force F, the operation lever 15 is inclined by ϑ, but the operation lever
15 slides on the pressing plate 14 to press, for example, the pressure sensitive elements
13a, 13b, 13c and 13d immediately beneath the protrusion 14a of the pressing plate
14, so that position deviation does not occur, and thereby a proper operating force
can be applied.
[0046] As shown in Fig. 10 (a), (b) in the case of a small shape of the position input device,
when a proper operating force is applied to the pressure sensitive element 13a, 13b,
13c or 13d if the operation lever 15 is inclined by the force F, the number of parts
can be curtailed by combining the operation lever 15 and pressing plate 14 into one
body.
[0047] Fig. 11 shows a position input device having a spacer 21 placed between a lower film
9 and an upper film 12, together with pressure sensitive elements 13a, 13b, 13c and
13d, in which a certain clearance is set until the pressure sensitive elements 13a,
13b, 13c and 13d are actually pushed, so that errors due to slight contact with the
operation lever 15 may be avoided.
[0048] In fig. 12, the pressure sensitive elements 13a, 13b, 13c and 13d are changed in
resistance in the thickness direction by the pressing force, and by making use of
the fact that the resistance in the plane direction is extremely large so that the
change in its resistance can be ignored, the pressure sensitive element is composed
of one piece by providing a connecting part 22, without separating into individual
pressure sensitive elements, so that the number of steps in assembling is reduced
to 1/4.
[0049] Incidentally, the lower film 9 may be replaced by a printed wiring board which is
a rigid body.
[0050] Fig. 13 (a) and (b) relate to an input apparatus of the invention, in which the position
input device of the invention is built in the input apparatus possessing plural input
keys such as a full keyboard of a personal computer. The height of the operation lever
15 is same as the height of the adjacent peripheral input keys 15a, or set slightly
higher, and it can be very easily manipulated by the finger of the operation.
[0051] Figs. 14, 15 and 16 show pointing devices of other embodiments of the position input
device of the invention, and specifically in Fig. 14, a protrusion 14d is provided
on the circumference of the pressing plate 14, and by assembling the protrusion 14d
by matching with a guide groove 19 of the main body case (not shown), the protrusion
14d provided on the pressing plate 14 and the pressure sensitive elements 13a, 13b,
13c and 13d can be positioned easily.
[0052] The embodiment shown in Figs. 15 and 16 has the same purpose as the embodiment shown
in Fig. 14, and Fig. 15 shows an example of providing markings 20 on both main body
case (not shown) and pressing plate 14, and Fig. 16 shows an example in which the
outer shape of the pressing plate 14 is square, and the inside corners of the main
body case (not shown) are assembled so that pressure sensitive elements 13a, 13b,
13c and 13d and the pressing plate 14 may be watched, as being guided by tie pressing
plate 14.
1. A position input device comprising a lower film disposing independent electrodes in
four directions individually, an upper film disposing common electrode confronting
the independent electrodes, pressure sensitive elementsd isposed between the independent
electrodes and common electrode respectively,a pressing plate possessing protrusions
at the positions for pressing the pressure sensitive elements corresponding to the
independent electrodes and common electrode, and an operation lever for manipulating
the pressing plate.
2. A position input device of claim 1, wherein a rigid printed wiring board is used instead
of the lower film.
3. A position input device of claim 1, wherein the pressing plate and operation lever
are formed into one body.
4. A position input device of claim 1, wherein a spacer is disposed between the pressure
sensitive elements so that the pressure sensitive elements may not be pushed in other
time than in operation.
5. A position input device of claim 1, wherein pressure sensitive rubber is used as pressure
sensitive elements.
6. A position input device et claim 1, wherein pressure sensitive rubber is used as pressure
sensitive elements, and the individual pressure sensitive elements are formed into
one body with the connecting parts.
7. A position input device of claim 1, comprising an A/D converter connected to the independent
electrodes, and an operating unit connecting a memory unit in which the procedure
for processing the digital data obtained by the A/D converter is written, wherein
the memory unit possesses a table for converting the digital data obtained by the
A/D converter into an operating force of the operation lever or a moving speed corresponding
to the operating force of the operation level.
8. An input apparatus using a position input device of claim 1, possessing plural input
keys, and an operation lever set at a same height of the input keys or slightly higher,
adjacently to the input keys.