JPS61109178A - Writing type data input device - Google Patents

Abstract

PURPOSE:To eliminate the misrecognition of the form of a written character due to the holding posture of a writing tool, by setting a pair of elastic members attached with distortion gauges at positions having shifts at both sides by an approximately equal angle centering on a vertical line passing through a writing shaft. CONSTITUTION:At a writing type input part,the circumferential displacement of a writing shaft 46 which is caused by a writing action with contact secured between a writing surface and the tip (writing chip 46a) of the shaft 46 is detected by two distortion gauges 50t and 50s in the directions of T and S axes via plate springs 52 and 52. When a holding case is held in a correct posture so that a clip part is set right above, the spring 52 attached with the gauge 50t and the other spring 52 attached with the gauge 50s are shifted at both sides by an equal angle (45 deg.) centering on a vertical line (Y axis line) passing through the shaft 46.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a written data input device.

[Technical background of the invention]

The writing type data input device detects the displacement of the writing axis accompanying the writing motion, identifies the writing character shape (numbers, symbols, etc.), and inputs the data to the information processing section. Conventionally, a writing shaft is provided in a pen-shaped gripping case with its tip protruding from the tip of the case, and a writing shaft is placed inside the gripping case to accommodate the writing operation performed by pressing the tip of the writing shaft against a writing surface. There is a structure in which a plurality of piezoelectric elements are arranged to detect the displacement of a writing shaft whose tip side is displaced in a direction opposite to the writing direction.

However, since the conventional writing data input device described above detects the displacement of the writing shaft by directly contacting the piezoelectric element with the writing shaft, when an impact is applied to the writing shaft, this impact generates a piezoelectric element. There is a problem that the element may be destroyed.Also, since the piezoelectric element detects only when pressure is applied from the writing shaft, displacement of the writing shaft in any direction is not possible. In order to ensure reliable detection, four to eight piezoelectric elements must be arranged so as to surround the outer periphery of the writing shaft, so there is a problem that the piezoelectric elements are troublesome to assemble and have poor assembly efficiency.

For this reason, solutions to the above problem have been studied for some time.

Figure 11 shows a writing type data input device that the applicant is considering as a solution to the above problem.In principle, this writing type data input device can be used as a strain sensor to detect the displacement of the writing shaft. Using a gauge, this strain gauge is attached to an elastic member that is brought into elastic contact with the writing shaft, and the strain gauge is mechanically deformed by the deformation of the elastic member that elastically deforms with the displacement of the writing shaft. The displacement of the writing shaft is detected from the amount of electrical change corresponding to the amount of mechanical deformation.

To explain this writing type data input device, the 11th
In the figure, 1 is a pen-shaped cylindrical gripping case, and inside this gripping case 1, a writing shaft 2 has its tip connected to the case 1.
It is provided so as to protrude from the tip.

This writing shaft 2 is similar to, for example, a ballpoint pen refill (center core of a ballpoint pen), and the tip side of this writing shaft 2 changes as the writing action is performed by pressing the tip of the writing shaft against a writing surface (for example, a paper surface). It is provided so as to be displaced in a direction opposite to the writing direction.

3.3 is a grip case 1 located outside the writing shaft 2;
One of the leaf springs 3 is located directly above the writing shaft 2 when the grip case 1 is held diagonally to the writing surface with a predetermined side facing up. The other leaf spring 3 is arranged so as to be located right next to the writing shaft 2 (here, on the right side) in the above-mentioned writing state.

The base ends of the pair of leaf springs 3.3 are each fixed in the grip case 1, and the tips thereof are bent toward the writing shaft 2 and brought into elastic contact with the outer periphery of the writing shaft 2.

4x is the strain gauge in the X-axis direction attached to the outer surface of the leaf spring 3 of the pair of leaf springs 3.3 located right next to the writing shaft 2 in the writing state, and 4y is the other leaf spring, that is, the strain gauge in the writing state. This is a strain gauge in the Y-axis direction attached to the outer surface of the leaf spring 3 located directly above the shaft 2.
For example, x and 4y have a structure in which a silicon semiconductor film is coated on the outer surface of a flexible substrate a that is bonded to the leaf spring 3.

These strain gauges 4x and 4y generate mechanical deformation (strain deformation) due to the deflection deformation of the leaf spring 3.3 due to the displacement of the writing shaft 2, and convert the amount of mechanical deformation into an amount of electrical change. It has a characteristic as shown in FIG. 12, in which the resistance value increases due to compressive strain, and the resistance value decreases due to compressive strain.

Note that this strain gauge 4x, 4V is connected to the lead wire 5,
5 is connected to a written character recognition circuit (not shown) provided in the grip case 1, and a change in the resistance value of the strain gauge wire 4X, 4V is inputted as a voltage change to the written character recognition circuit. It has become.

On the other hand, 3a and 3a are the strain gauges 4X.

A pair of auxiliary leaf springs are provided to face the leaf spring 3.3 with the writing shaft 2 in between,
These auxiliary leaf springs 3a, 3a are also held at their base ends by the case 1.
The tip is bent toward the writing shaft 2 and brought into elastic contact with the outer periphery of the writing shaft 2.

The auxiliary leaf springs 3a, 3a press the writing shaft 2 toward the leaf spring 3.3 to hold the writing shaft 2 in a neutral state. It is held in a neutral position by being equally pressed from four directions by leaf springs 3, 3.

To explain the operation of this writing-type data input device, this writing-type data input device, like writing instruments such as ballpoint pens and fountain pens, holds the grip case 1 diagonally to the writing surface (perpendicularly to the writing surface). (Position tilted towards you from a standing position)
As shown in FIG.
It is used by holding it obliquely to the writing surface so that the side on which the axial strain gauge 4y is provided faces upward.

Therefore, when the tip of the writing shaft 2 is pressed against the writing surface while holding the grip case 1 diagonally as described above, the force of pressing the writing shaft against the writing surface causes the tip side of the writing shaft 2 to move as shown in FIG.
It is displaced in the Y-axis direction shown in a), and due to this displacement of the writing shaft 2, the leaf spring 3 to which the Y-axis direction strain gauge 4y is attached is pushed by the writing shaft 2 and deflected outward (upwards). When the leaf spring flexes outward in this way, this leaf spring 3
The Y-axis direction strain gauge 4y attached to the outer surface of the b) As shown on the Y-axis side, the reference voltage vO to V
It changes up to l.

Hereinafter, the amount of change in the output voltage at the time when the tip of the writing shaft is pressed against the writing surface will be referred to as an initial bias.

In this writing preparation state, that is, in a state where the tip of the writing shaft is simply pressed against the writing surface, the writing shaft 2 does not displace in the lateral direction (X-axis direction), so at this time, the X-axis strain gauge 4
x does not undergo strain deformation, so the output voltage V1 indicating the writing axis displacement in the X-axis direction at this time is the same as the reference voltage VO (Vl - VO
).

That is, in this writing preparation state, there is no initial bias in the output indicating the writing axis displacement in the X-axis direction (hereinafter referred to as the X-axis output).

Next, when writing is started from this writing preparation state, writing pressure is applied to the writing shaft 2 by this writing operation, so that the amount of displacement of the writing shaft 2 becomes even larger.

For example, if you input the number ``1'' by hand, the number ``1'' is normally written in a diagonal line from the upper right to the lower left, so in this case, the writing axis 2 will be displaced diagonally to the upper right. Therefore, when writing the number "1", both leaf springs 3, 3 are deflected outward, and as a result, the Y-axis strain gauge 4y is further distorted in the compression direction, and the X-axis Since the directional strain gauge 4x also produces compressive strain, when writing the number “1”, the first
A Y-axis output and an X-axis output with waveforms as shown in the upper column of FIG. 3(b) are obtained. ■2 indicates the output voltage during this writing.

Next, to explain the case where the subtraction symbol "-" is input in writing, the subtraction symbol "-" is written almost horizontally from left to right, so in this case the writing axis 2 is displaced to the left. . Therefore, when writing the subtraction symbol 11 I+,
The Y-axis strain gauge 4y undergoes compressive strain in response to writing pressure, but the X-axis strain gauge 4x has a flat spring 3 attached to it that follows the leftward displacement of the writing shaft 2, causing the inside (writing This causes tensile strain to occur due to the flexural deformation on the shaft side), and therefore, the subtraction symbol 11 1
1, the Y-axis output and the X-axis output of waveforms as shown in the lower column of FIG. 13(1)) are obtained.

That is, this writing type data input device has a flat spring 3,
3 is brought into elastic contact with the leaf springs 3, 3, and a tensile or compressive strain is generated due to the elastic deformation of the leaf spring 3.3 in the outward and outward directions as the writing shaft 2 is displaced, thereby causing an X-axis direction strain that increases or decreases the resistance value. By installing a gauge 4x and a Y-direction strain gauge 4y, the shape of a written character is recognized by a combination of changes in the X-axis output and Y-axis output due to strain deformation of both strain gauges 4x and 4y.

Therefore, according to this writing type data input device, since the strain gauges 4X and 4V are not in direct contact with the writing shaft 2, there is no fear that the strain gauges 4x and 4y will be destroyed even if an impact is applied to the writing shaft 2. 2 strain gauges 4x,
4y alone can detect the displacement of the writing shaft 2 in any direction, so it is only necessary to provide the above two strain gauges 4X and 4y as sensors for detecting the writing shaft displacement. It is also easy to incorporate 4x and 4y.

[Problems with background technology]

However, in the above-mentioned writing type data input device, the X-axis direction strain gauge 4× is provided so as to be located right next to the writing shaft 2 in the writing preparation state where the grip case 1 is gripped diagonally.
In the writing preparation state, no initial bias is generated in the X-axis output. 4x is positioned directly beside the writing axis 2), there is a problem in that the handwritten character shape cannot be correctly recognized.

To explain an example of misrecognition of this written character shape, Figure 14 (
a) is the strain gauge 4x when gripping case 1 is gripped in a position rotated clockwise to some extent from the correct gripping position.
, 4y. In this case, the Y-axis strain gauge 4y is shifted to the right from the position directly above the writing axis 2,
The strain gauge 4× in the X-axis direction is shifted downward from the position directly beside the writing shaft 2.

When the tip of the writing shaft 2 is pressed against the writing surface in this state, the leaf spring 3 to which the Y-axis strain gauge 4y is attached deforms outward as the writing shaft 2 is displaced in the Y-axis direction. , the leaf spring 3 to which the X-axis direction strain gauge 4X is attached is deformed inward. Therefore, at this time, the Y-axis direction strain gauge 4y produces compressive strain and the Y-axis output increases as shown in FIG.
), the strain gauge 4x in the X-axis direction generates tensile strain, and
The shaft output becomes the initial bias voltage of voltage value ■1.

Then, when the number "1" is input by hand, the Y-axis strain gauge 4y undergoes further compressive strain and the Y-axis output becomes ■2, and the X-axis strain gauge 4x further undergoes tensile strain and the X-axis output becomes V2. Therefore, in this case,
The X-axis output and Y-axis output have the waveforms shown in the upper column of FIG. 14 (1)).

In other words, the waveform of the X-axis output when gripping case 1 is gripped in a position rotated clockwise to a certain extent from the correct gripping posture and the number "1" is input by hand is the same as the waveform of the The waveform has the opposite polarity to the waveform of the X-axis output when 1n is inputted by hand, and therefore, even though the number ``1pa'' is inputted by hand, the written character "1" is different from other character shapes. (The waveforms of the X-axis output and Y-axis output at this time are the Since it is similar to the output waveform, 41'
The written character form of f is erroneously recognized as a subtraction symbol "~". )
. The waveforms of the X-axis output and Y-axis output when the subtraction symbol "-'' is written are as shown in the lower column of FIG. 14(b), and this waveform is Since the waveforms of the X-axis output and Y-axis output are similar to when the subtraction symbol +1 ++ is input by hand while gripping the device in the correct posture, there is no need to worry about subtraction symbol 11 IT error a FA.

This also applies when writing is performed while gripping the gripping case 1 in a position rotated counterclockwise to some extent from the correct gripping position. In that case, the X-axis output is Since the waveform is an inversion of the waveform on the side, contrary to the above, the written character "-" is mistakenly interpreted as the number "1".

(Object of the Invention) This invention was made in view of the above-mentioned circumstances, and its purpose is to detect the displacement of the writing shaft using only two strain gauges. However, it is an object of the present invention to provide a writing type data input device that does not have to worry about misrecognizing a written character shape even when handwritten input is performed while holding the grip case in a position rotated in the circumferential direction from the correct position.

[Summary of the invention]

In other words, the present invention provides a method in which when a pair of elastic members to which a strain gauge is attached are gripped obliquely to a writing surface with the gripping case in the correct posture with a predetermined side facing up, the pair of elastic members By arranging the lines so that they are shifted by approximately equal angles on both sides of the line, even when the grip case is gripped in a position rotated in the circumferential direction from the correct gripping position and a writing input is performed, the direction of displacement of the writing axis remains unchanged. The deformation of both strain gauges is made to have the same tendency as the deformation of both strain gauges when the grip case is held in the correct posture and a written input is made.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings, taking a handwritten input type small electronic calculator as an example.

The handwriting input type small electronic calculator of this embodiment has a length of 1
It is a pen-shaped device measuring 50 to 200 mm, with the central part to the proximal end serving as the computer main body, and the distal end serving as a writing input part.

To explain the configuration of this handwritten input type small electronic calculator,
1 to 5, 10 is a pen-shaped gripping case, and this gripping case 10 is a case (
It consists of a main body case 10a (hereinafter referred to as the main body case) and a writing input unit case (hereinafter referred to as the input unit case) iob. This main unit case 10a and input unit case 10b
are all cylindrical, the main body case 10a has a diameter of 12 to 15n+m, and the input case 10b has a diameter of 12 to 15n+m.
is said to have a diameter of 10 to 12 III.

The main body case 10a is made by covering the outer periphery of a synthetic resin shaft cylinder 11 with a metal outer cylinder 12 except for its tip, and one side of the shaft cylinder 11 has a horizontally long opening along the case axis direction. 11a, and the metal outer cylinder 12 is provided with an opening 12a that corresponds to the opening 11a of the shaft cylinder 11 and whose length and width are slightly smaller than the opening 11a.

13 is a flat display panel fitted into the opening 11a of the shaft tube 11, and the periphery of the display panel 13 is as follows:
The peripheral edge of the opening 12a of the metal outer cylinder 12 is covered.

A display window 14 fitted with a transparent plate 14a is provided at one end of the display panel 13, and a skip (SK> key 15) and a sub sea fence (SB) key 16 are provided at the other end. A clear (C) key 17 is arranged in one line.

Further, a liquid crystal display element 18 is arranged inside the shaft cylinder 11 so as to face the display window 14.
A wiring board 19 having a length extending substantially over the entire length of the display panel 13 is provided behind the display panel 8 .

This wiring board 19 has, on its back side, a written character shape recognition circuit that recognizes written character shapes (numbers, symbols, etc.) based on input from a writing type input section, and performs calculation processing based on input data from this recognition circuit. The LSI chip 20 on which information processing circuits, display drive circuits, etc. are formed, and other circuit parts (
(not shown), and this wiring board 19 is fixed to a board support portion 21.21 formed inside the shaft cylinder 11 with screws or the like.

In FIGS. 3 and 5, reference numeral 22 denotes an interconnector 23 for connecting each terminal of the liquid crystal display element 18 and liquid crystal display element connection terminals (not shown) arranged on the surface of the wiring board 19. is a spacer interposed between the back surface of the liquid crystal display element 18 and the wiring board 19, and the liquid crystal display element 18 is connected to the wiring board 19 and the transparent plate 14a of the display window 14 via the ink connector 22 and the spacer 23. is sandwiched between.

Further, in FIG. 3, reference numerals 24 and 24 are fixed contacts formed on the surface of the wiring board 19 in correspondence with the respective keys 15, 16, and 17, and 25 is a fixed contact formed on the fixed contact forming portion of the wiring board 19. This is a rubber sheet made of rubber. This rubber sheet 25 has bulges that contact the back surfaces of the keys 15, 16, and 17 at portions corresponding to the fixed contacts 24.24, and the inner surface of each bulge has a key 15.16
．． The fixed contact 2 is deformed by the deformation of the bulge due to the pressing operation of 17.
A movable contact 26.26 is provided which is contacted by 4.24, and this movable contact 26.26 and said fixed contact 24.2
4 form a key switch that is turned on by pressing the keys 15, 16, and 17.

Further, a mode changeover switch 27 that also serves as a power switch is provided in the base end of the shaft cylinder 11. This mode changeover switch 21 consists of a rotary switch that is changed over by rotating a knob 27a, and the mode changeover switch 27 is connected to the wiring board 1 by a negative wire 28.
9 is connected.

Reference numeral 29 denotes a removable cap screwed onto the base end of the shaft cylinder 11, and the mode changeover switch 27 is operated by removing this cap 29. A sound emitting hole 30.30 is opened in the end face of this cap 29, and a piezoelectric buzzer 31 is provided inside this cap 29. This piezoelectric buzzer 31 is driven by a sound signal from the LSI chip 20 every time the writing character shape identification circuit of the LSI chip 20 identifies a writing character shape for one character based on an input signal from the writing type input section. The piezoelectric buzzer 31 is attached within the cap 29 by bonding a diaphragm 31a, which also serves as an outer electrode, to the inner surface of the end surface of the cap 29. 32a and 32b are piezoelectric buzzer connection spring terminals provided at the base end of the shaft tube 11; one of the spring terminals 32a is in contact with the inner electrode surface of the piezoelectric buzzer 31, and the other spring terminal 32b is It is in contact with the diaphragm 31a of the piezoelectric buzzer 31. Note that each spring terminal 32a, 32b is connected to the wiring board 19 by a lead wire 33.

Furthermore, a battery storage section 34 is formed at the tip of the shaft tube 11 that is not covered with the metal outer tube 12, and is open to the side surface thereof. Small size batteries 35.35 are stacked in series and stored. This battery 35.35 is held between a negative battery contact spring 36 made of a coil spring and a positive battery contact spring 37 made of a plate spring.
The other end of 6 is fixed to the wiring board 19 and connected to the negative battery connection terminal on the wiring board 19 surface.

On the other hand, the positive electrode side battery contact spring 37
It is removably installed inside. This positive electrode side battery contact spring 37 is integrally formed with an extending piece 37a that extends to the open part of the battery storage section 34, and this positive electrode side battery contact spring 37 is attached to the tip of the extending piece 37a. The lead wire 38 is connected to the positive battery connection terminal on the wiring board 19 surface.

Reference numeral 39 denotes a cushioning material that presses down the battery 35.35, and this cushioning material 39 is integrated with the positive battery contact spring 37 by inserting the extension piece 37a of the positive battery contact spring 37 therethrough. .

Further, reference numeral 40 denotes a metal battery cover that covers the open portion of the battery storage portion 34, and this battery cover 40 has a cylindrical shape that covers the entire circumference of the tip portion of the shaft tube 11. The battery cover 40 is slidably and rotatably fitted onto the outer periphery of the barrel 11, and is screwed into a threaded portion formed on the outer periphery of the barrel 11 at its base end.

When replacing the batteries 35 and 35, the battery cover 40 is rotated to unscrew it from the barrel 11, and then slid toward the writing input section as shown by the chain line in FIG. To replace the batteries 35 and 35, open the battery compartment 34 by sliding the battery cover 40 toward the writing input section, and remove the positive battery contact spring 37 together with the cushioning material 39. This is done by removing the battery 35.35 from inside the battery storage part 34 and storing a new battery 35.35, then attaching the cushioning material 39 and the positive battery contact spring 37 again and returning the battery cover 40 to its original position. It has become.

In addition, in FIG. 2, 41 indicates the main body case 10a.
This clip 41 is provided on the outer side of the proximal end of the main body case 10a, and this clip 41 is provided at a position shifted approximately 90 degrees from the position of the display panel 13 in the circumferential direction of the main body case 10a.

Next, to explain the structure of the writing type input section, the case 10b of this writing type input section includes a base-end shaft tube 42 made of synthetic resin and a base-end shaft tube 42, as shown in FIGS. 3 and 4. Side shaft cylinder 4
It consists of a metal outer cylinder 43 whose base end side is fitted to the outer periphery of the metal outer cylinder 43, and a tapered base member 44 which is fitted to the distal end of the metal outer cylinder 43 and tapers toward the distal end. Inside the metal outer cylinder 43, there is a distal end thereof and a proximal shaft cylinder 42.
An insulating cylinder 45 made of synthetic resin is fitted and fixed except for the part that fits into the insulating cylinder 45.

The proximal shaft tube 42 and the base member 44 each have a writing shaft insertion hole 42a having a diameter slightly larger than the writing shaft 46 at the center thereof.
, 44a are covered with a membrane, and the writing shaft 46 has a proximal end protruding from the base end of the proximal barrel 42 and a distal end protruding from the tip of the base member 44. and are inserted into the writing shaft insertion holes 42a and 44a of the base member 44.

This writing shaft 46 is similar to a ballpoint pen refill (center core of a ballpoint pen) in which a writing tip 46a having a writing ball is attached to the tip of the ink cylinder.In this embodiment, the ink cylinder is made of metal as the writing shaft 46. We are using the following.

41 is a sphere having a ventilation hole that is fitted and fixed to the base end of the writing shaft 45; 48 is a cylindrical sphere receiver that is screwed to the base end surface of the base-side barrel 42; It is pressed against the inner part of the spherical receiver 48 by a coil spring 49 and is rotatably held within the spherical receiver 48 .

This ball receiver 48 connects the base end of the writing shaft 46 to the ball 41.
The writing shaft 46 is supported by a spherical support 4 so that it can tilt in any direction using its base end as a fulcrum.
As a result, the writing shaft 46 is supported by the writing shaft insertion hole 44a of the cap member 44 when the writing shaft 46 presses the writing tip 46a at the tip against the writing surface to write numbers, symbols, etc. It is designed to be displaced in the direction opposite to the writing direction by the amount of clearance between the writing direction and the writing direction.
"The spherical receiver 48 is made of a leaf spring, and a sensor is provided on its outer surface to detect when a force is applied to the writing shaft 46 in the axial direction (Z-axis direction), as shown in FIG. Semiconductor strain gauge 5oz similar to the strain gauge shown in
is fixed with adhesive. This strain gauge 502 prevents mechanical deformation by deforming the spherical receiver 48, which elastically deforms in the axial direction due to the force applied in the axial direction of the writing shaft 46 when the tip (writing tip 46a) of the writing shaft 46 is pressed against the writing surface. This mechanical deformation amount is converted into an electrical change amount, and when this strain gauge 5oz is subjected to tensile strain, its resistance value increases. This strain gauge 50z in the Z-axis direction is connected to the wiring board 19 of the computer main body by a lead wire 51.

In addition, in the input unit case 10b, three horizontally long leaf springs 52, 52, and 528 are installed along the length direction of the writing shaft in the space between the base end shaft cylinder 42 and the base member 44. 46, and two of the leaf springs 52 and 52 are provided with T on the outer surface thereof as a sensor for detecting the displacement of the writing shaft 46 in the circumferential direction due to the writing operation. An axial strain gauge 50t and an S-axial strain gauge 50S are each fixed with adhesive.

The pair of leaf springs 52 and 52 to which the strain gauges 50t and 50s are attached, when the gripping case 10 is gripped diagonally to the writing surface in a correct posture with the predetermined side, that is, the side on which the clip 41 is provided, facing up. The pair of leaf springs 52 and 52 are provided so as to be located above the center of the writing shaft 46, and when the grip case 10 is gripped in the correct posture as described above, the pair of leaf springs 52. .5
2 is approximately 4 on either side of the vertical line passing through the writing axis 46.
They are arranged so that they are offset by 5 degrees.

The other leaf spring 52a is an auxiliary leaf spring for pressing the writing shaft 46 toward the pair of leaf springs 52 and 52 to hold the writing shaft 46 in a neutral state. The spring 52a is attached to the side opposite to the pair of leaf springs 52.52 across the writing shaft 46.
It is provided so as to directly face an intermediate position between 52 and 52.

Each of the leaf springs 52, 52, 528 has its base end screwed to the outer periphery of a cylindrical protrusion 42b protruding from the tip of the proximal shaft cylinder 42, so that it can be held in a cantilevered state within the input case 10b. This fixed portion is elastically deformed in the radial direction of the writing shaft 46 at the distal end portion thereof. In addition, the tip of each leaf spring 52, 52, 52a is
As shown in FIG. 1, it is bent toward the writing shaft 46 side, and its tip is brought into elastic contact with the outer periphery of the writing shaft 46 with a constant spring force, so that the writing shaft 46 is in a neutral state, that is, the writing shaft 46 is maintained at the center of the writing shaft insertion holes 42a and 44a of the proximal shaft tube 42 and the base member 44.

Each of the leaf springs 52, 52, 52a is made of stainless steel, has a thickness of 0.5III111, a width of approximately 4+nm, and a length of the bent portion of approximately 10IllIH.
．． 52.528 has a spring force that causes the tip of the leaf spring to displace approximately Q, 4 mm, when a writing pressure of I kg (pressure that displaces the writing shaft 46 in the circumferential direction) is applied to the writing shaft 46. Note that there are individual differences in writing pressure, but this writing pressure is approximately 0.
゜5~1.5Kg (normally about 0.7Kg), so if the spring force of the leaf spring 52, 52, 52a is selected to the above value, the leaf spring will remain strong even if there are individual differences in writing pressure. 52゜5
2, 52a can be sufficiently deflected and deformed by writing pressure. However, if the writing pressure exceeds 1.5 kg, the amount of deflection of the leaf spring 52.52.52a becomes too large and the leaf spring becomes fatigued due to repeated deflection and deformation. .The diameter of the writing shaft insertion hole 44a of the cap member 44 is selected so that when the deflection of the finger 52a exceeds a certain level, the writing shaft 46 hits the cap member 44 and is prevented from further deformation. 52.52.52
The durability of a is guaranteed.

Strain gauge set attached to the pair of leaf springs
, 50s also has a leaf spring of 52°52 as shown in Figure 1.
The strain gauge is a semiconductor strain gauge in which a silicon semiconductor film is deposited on the outer surface of a flexible substrate a that is bonded to a flexible substrate a.

This strain gauge 50°C, 50S generates mechanical deformation due to the deflection deformation of the leaf spring 52, 52 due to the displacement of the writing shaft 46, and converts this mechanical deformation amount into an electrical change amount. , 50s also has the characteristics shown in FIG. 12, in which its electrical resistance value increases due to tensile strain, and its resistance value decreases due to compressive strain. Each of the strain gauges 50t and 50s is connected to the wiring board 19 of the calculation main body section by lead wires 53 and 53. In addition, the lead wire 53.53
is guided into the main body case 10a through a lead wire insertion hole (not shown) generally provided in the base end side shaft cylinder 42.

Further, the base of the base member 44 extends from the distal end of the metal outer cylinder 43 to the distal end of the insulating inner cylinder 45 and is fitted inside thereof so as to be slidable in the circumferential direction and the axial direction. The portion of the member 44 that fits into the insulating inner cylinder 45 includes:
As shown in FIG. 6, an inclined groove 55 is formed to slidably engage with a protrusion 54 (see FIG. 3) protruding from a part of the inner side of the tip edge of the insulating inner cylinder 45.

By rotating this base member 44, the base member 44 is moved in the axial direction by the guiding action of the inclined groove 55, and when using the writing input type small electronic calculator, the base member 44 is moved from its tip to the writing tip at the tip of the writing shaft 46. 46a is moved to the state where it protrudes, and when the writing input type small electronic calculator is not used, it is moved to the tip side as shown by the chain line in FIG.
It is designed to protect the writing tip 46a at the tip of 6.

The above-mentioned writing type input section has strain gauges of 50t and 50s.
The proximal ends of the leaf springs 52, 52 and the auxiliary leaf spring 52a with attached leaf springs 52, 52 and 52a are fixed to the tip of the proximal shaft tube 42, and the writing shaft 46 is inserted into the proximal shaft tube 42 to open the proximal shaft. After attaching the ball receiver 48 to the base end of the cylinder 42, the insulating inner cylinder 45 is fitted and fixed in advance, and the metal outer cylinder 43, which has the cap member 44 fitted to the tip, is inserted into the cap member 44 through the writing shaft 46, and then the writing shaft 46 is inserted into the base. This metal outer cylinder 43 fits on the outside of the end side shaft cylinder 42.
is assembled by caulking to the proximal barrel 42 with its base end protruding from the base end of the proximal barrel 42. The base end of the tube 43 is fitted into the tip of the shaft tube 11 of the main body case 10a and caulked to the shaft tube 11, so that it is integrated with the computer main body.

The writing type input unit converts circumferential displacement of the writing shaft 46 caused by a writing operation performed by contacting the tip (writing tip 46a) of the writing shaft 46 with a writing surface into a T-axis via leaf springs 52, 52. Two strain gauges 50t in direction and S axis direction
, 50 seconds, and this writing input unit and the writing type HH4 circuit formed in the LSI chip 20 of the computer main body constitute a writing type data input device.

To explain the operation of the writing input section, the strain gauge 50
When no external force is applied to the writing shaft 46, the leaf springs 52, 52 and the auxiliary leaf spring 52a to which the t. The initial posture of pressing the writing shaft 46 with force is maintained.

Then, when the tip end of the writing shaft 46 is displaced upward in FIG. , 52 are both pushed by the writing shaft 46 and deflected outward, causing both strain gauges SOt.

50 seconds causes compressive strain and its resistance value decreases.

Further, when the tip side of the writing shaft 46 is displaced downward, the leaf springs 52 and 52 follow the displacement of the writing shaft 46 by their spring force and are deflected inward, causing both strain gauges 50t,
50 seconds causes tensile strain and its resistance value Ry2 increases.

Furthermore, when the tip side of the writing shaft 46 is displaced to the left in FIG. The right leaf spring 52 to which the 50s is attached follows the displacement of the writing shaft 46 and bends and deforms inwardly, so at this time, the T-axis direction strain gauge 50t generates compressive strain and its resistance value decreases, and the S-axis The directional strain gauge 50s generates tensile strain and its resistance value increases.

Further, when the tip side of the writing shaft 46 is displaced to the right, the left leaf spring 52 to which the T-axis strain gauge 50t is attached is deflected inward, and the right leaf spring 52 to which the S-axis strain gauge 50s is attached is outward. At this time, the T-axis strain gauge 50t generates tensile strain and its resistance value increases, and the S-axis strain gauge 50t
s produces compressive strain and its resistance value decreases.

At this time, the auxiliary leaf spring 52a is deflected inward or outward as the writing shaft 46 is displaced.

Next, to explain the written character shape recognition circuit, FIG. 8 shows the circuit of the handwritten input type small electronic calculator, and the written character shape HH circuit includes a data memory section 60, a registered standard pattern section 61, It consists of a recognition calculation section 62.

The T-axis strain gauge 50, the S-axis strain gauge SO3, and the Z-axis strain gauge 502 are connected in series with fixed resistors 64a, 64b, and 64c, respectively, and their connection points are A T-axis signal output amplifier 63t and an S-axis signal output amplifier 63s, respectively.
A two-axis signal output amplifier 63z is connected, and each strain gauge 50t, 50s, 50z is connected to a low potential V.
Fixed resistor 64a connected to the oo (-3V) side.

64b and 64c are connected to the high potential Vss (OV) side.

The outputs of the amplifiers 63t, 63s, and 63z are connected to A/D:l inverters 65t, 65s, and 65s, respectively.
The data is input to the data memory unit 60 via the data terminal 65z.

To explain the operation of this handwritten character recognition circuit, when using a handwriting input type small electronic calculator, this circuit is activated by switching the power switch/mode selector switch 27 to the computer mode and turning on the computer power supply circuit 66. becomes.

Then, as shown in FIG. 7, hold the grip case 10 with the clip 41 on top, as shown in FIG. When the tip of the writing shaft 46 is pressed against the writing surface P in this writing posture by holding it in an attitude tilted to the side, the spherical receiver 48 expands and deforms due to the pressure in the axial direction applied to the writing shaft 46.
As a result, the Z-axis direction strain gauge 50z generates tensile strain, and its resistance ftaRZ increases.

When the resistance value RZ of the Z-axis direction strain gauge 5oz increases in this way, this strain gauge 50Z and the fixed resistor 64c
The divided voltage between the Z-axis signal output amplifier 63z changes.
, a voltage closer to the high potential Vss side is output. The output of this amplifier 63z (hereinafter referred to as 2-axis output) is converted into a digital signal by an A/D converter 65z and inputted to the data memory section 60, and from this data memory section 60 to the CPU (central information processing unit) 67. This Z-axis output is also input to the CPU 67.
, the CPU 67 inputs its reset terminal R
A reset signal is given to the timer 68 from the timer 68 to reset the timer 68.

Further, the data memory section 60 outputs the T-axis signal output amplifier 63 only when the Z-axis output is input thereto.
It accepts the output of the t- and S-axis signal output amplifier 63s, and therefore, when there is no writing pressure in the axial direction of the writing shaft 46 (when the tip of the writing shaft is not pressed against the paper surface), The outputs of the T-axis signal output amplifier 63t and the S-axis signal output amplifier 638 are sent to the data memory section 60.
It is no longer entered in .

Therefore, if we now hold the gripping case 10 in the correct posture with the clip 41 directly above it and holding it diagonally, in this correct gripping posture, the T-axis Leaf spring 5 with 50t directional strain gauge attached
2 and a leaf spring 5 with an S-axis strain gauge 50s attached.
2 are at positions shifted by equal angles (45 degrees) on both sides of the vertical line (Y-axis line) passing through the writing axis 46.

When the tip of the writing shaft 46 is pressed against the writing surface P while holding the grip case 10 in the correct posture, the writing surface P
The tip of the writing shaft 46, which is pressed obliquely to the strain gauge sot, is displaced directly upward (Y-axis direction).
, 50s are attached to the plate springs 52, 52 are deflected outward to the same extent, and the T-axis strain gauge 50t and the S-axis strain gauge 50s attached to both temporary springs 52, 52 are both compressively strained. This causes the resistance values Rt and Rs to decrease.

In this way, when the resistance values Rt and Rs of the T-axis strain gauge 50t and the S-axis strain gauge 50s decrease, the strain gauges 50t and 50s and the fixed resistance 64a decrease.
, 64b changes, and the output of the T-axis signal output amplifier 63°C (hereinafter referred to as T-axis output) and the output of the S-axis signal output amplifier 63s (hereinafter referred to as S export power) are at a low potential Vpp. Because it's on the side, this T-axis signal output amplifier 63t
An initial bias of one point (■) shown in FIG. 9(b) occurs between the T-axis output of the S-axis signal output amplifier 63s and the S-export power of the S-axis signal output amplifier 63s.

If the number "1" is written in this state, the writing shaft 46 is further displaced upward from the initial state due to the writing pressure, so when the number "1" is written,
T-axis strain gauge 50t and S-axis strain gauge 5
0s undergoes further compressive strain, and its resistance values Rt and Rs further decrease. Therefore, when inputting the number "1" by hand,
The T-axis output of the T-axis signal output amplifier 63t and the S-axis output of the S-axis signal output amplifier 63S form a waveform of an output voltage 2 as shown in the upper column of FIG. 9(b).

Note that since the number "1" is normally written in a diagonal line from the upper right to the lower left, the writing shaft 46 is displaced diagonally to the upper right. Because the S-axis strain gauge 50s on the right side has a slightly larger compressive strain than the T-axis strain gauge 50℃,
The amount of change in the output voltage with respect to the initial bias (1) is slightly larger for the S-axis output.

Next, if the subtraction symbol "-" is input by hand, the subtraction symbol "-" is written almost horizontally (in the X-axis direction) from left to right, so in this case, the writing axis 46 is Displace to the left from the state.

When the subtraction symbol "-" is written, the left T-axis direction strain gauge 50t undergoes further compressive strain and its resistance value Rt decreases.
The shaft output is even closer to the low potential VDD side than the initial bias ■1, but the S-axis strain gauge 50 on the right
Conversely, the resistance value Rs of s increases in order to reduce the degree of compressive strain, and the S-axis output of the S-axis signal output amplifier 63s becomes an output that is closer to the high potential Vss than the initial bias V1.

Therefore, when writing the subtraction symbol "'-", the T-axis output of the T-axis signal output amplifier 63t and the S-axis signal output amplifier 63s
The S-axis output becomes the waveform of the output voltage V2 as shown in the lower column of FIG. 9(b).

Next, a case will be described in which a handwritten input is performed without gripping the gripping case 10 correctly as described above.

For example, if the gripping case 10 is gripped in a position rotated clockwise to some extent from the correct gripping position, then the leaf spring 52.52 to which the strain gauge sot, 50s is attached will move as shown in FIG. 10(a). As shown, the position is shifted clockwise from the position when gripping case 10 is gripped in the correct posture, but the rotation angle of gripping case 10 when gripping case 10 is rotated in the circumferential direction is at most Since the angle is about 25 degrees, hold the case 10 in the correct posture.
When gripped, the leaf springs 52 and 52, which are at an angle of 45 degrees to the X axis, will not shift beyond the center of the writing shaft 46 to the opposite side.

Therefore, even when gripping case 10 is gripped from the correct gripping position to the position rotated clockwise, the writing shaft 4
When the tip of 6 is pressed against the writing surface, both leaf springs 52,52
is deformed outward, so the T-axis direction T-axis signal output amplifier 6
An initial bias at the V1 point shown in FIG. 10(b) is generated in the T-axis output of 3t and the S-axis output of the S-axis signal output amplifier 63s.

If the number "1" is input in this state, the T-axis strain gauge 50t and the S-axis strain gauge 50s are further compressively strained due to the upward displacement of the writing shaft 46, resulting in a resistance value Rt.

Rs further decreases, and the T-axis output of the T-axis signal output amplifier 63t and the S-axis output of the S-axis signal output amplifier 633 become the first
The waveform of the output voltage V2 is as shown in the upper column of FIG. 0(b).

In this case, since the strain gauges 50t and 50s are deviated in the above-mentioned direction, T
The degree of compressive strain of the axial strain gauge 50t becomes slightly larger, and conversely, the degree of compressive strain of the S-axis strain gauge 50s becomes slightly smaller, so the voltage value v2 of the T export force and the S-axis output is Although the voltage value is slightly different from the voltage value when the number "1" is input by hand while gripping the gripping case 10 in the correct posture, the waveforms of the T export force and S export force are the same as when gripping the gripping case 10 in the correct posture and inputting the number "1" by hand. The waveform will have the same tendency as the waveform when inputting by hand.

Next, suppose that the subtraction symbol "-" is input by hand. When writing the subtraction symbol "-", the left T-axis direction strain gauge 50
t further compressive strain, and the right S-axis direction strain gauge 50s conversely reduces the degree of compressive strain, so the T-axis output of the T-axis signal output amplifier 63t and the S-axis signal output amplifier 6
The S-axis output of 3S has a waveform as shown in the lower column of FIG. 10(b).

When inputting the subtraction symbol "-" by hand, the strain gauges 50t and 50s are deviated in the above direction, so the grip case 10 is held in the correct posture and the subtraction symbol "-" is input.
-”, the degree of compressive strain in the T-axis direction strain gauge 50 is slightly smaller, and S
Since the degree of tensile strain of the axial strain gauge 50S becomes slightly larger, the voltage value V2 of the T export force and the S export force can be calculated by holding the grip case 10 in the correct posture and subtracting the symbol "-".
Although it is slightly different from the voltage value when inputting by hand, the waveforms of the T-axis output and S export force have the same tendency as the waveform when gripping case 10 is held in the correct posture and the subtraction symbol "-" is input by hand. The waveform becomes

This is also the case when the gripping case 10 is held in a counterclockwise rotation position opposite to that described above and a written input is performed. In this case, the T-axis strain gauge 50t and the S-axis strain gauge 503 are Although the degree of tensile strain is opposite to when gripping case 10 is gripped in a clockwise rotation position, the strain direction of this strain gauge sot 50s remains unchanged, so in this case as well, the T-axis output and S export force are The waveform has the same tendency as the waveform when handwriting is input while holding the grip case 10 in the correct posture.

That is, in this writing type data input device, a pair of leaf springs 52° 52 to which strain gauges of 50° C. When this pair of leaf springs 5
2.52 is positioned so that it is shifted by approximately equal angles on both sides of the vertical line passing through the writing axis 46, so that the gripping case 10 can be gripped in a position rotated in the circumferential direction from the correct gripping position. Even if you input by hand, the writing axis 46
Strain deformation of both strain gauges due to the displacement of 50 s is caused by the displacement of both strain gauges 50t, 50 when the gripping case 10 is held in the correct posture and written input is performed.
Therefore, this writing type data input device uses two strain gauges 5.
Although the displacement of the writing shaft 46 is detected in only 0t and 50s, there is a concern that the writing shape will be misrecognized even if the gripping case 10 is held in a position rotated in the circumferential direction from the correct position and a written input is performed. There isn't.

To explain the recognition of this written character shape, as shown in FIG. 8, the T-axis output of the T-axis signal output amplifier 63t,
The S-axis output of the S-axis signal output amplifier 638 is converted into a digital signal by the A/D converters 65t and 653, inputted to the data memory section 60, and inputted from the data memory section 60 to the recognition calculation section 62. It has become.

The registered standard pattern section 61 also includes the T-axis output and S
Standard glyph patterns such as numbers and operation symbols that correspond to combinations with shaft outputs are registered, and the recognition calculation section 62 uses the input data from the data memory section 60 and the standard glyph patterns from the registered standard pattern section 61. The glyph pattern with the highest correlation is selected by comparison, and its glyph pattern number is input to the CPU 67.

Also, when you finish writing one number or symbol, the writing axis 4
When the tip of 6 is separated from the writing surface, the Z-axis direction strain gauge 50z returns from the tensile strain state and the Z export force from the two-axis signal output amplifier 63Z disappears. When this two output power is exhausted, a start signal is sent from the set terminal S of the CPU 67 to the timer 68, and the timer 68 starts counting clock pulses φ.

Then, when the timer 68 counts the preset number of clock pulses and times up, the timer 68
A carry signal is sent from the CPU 67 to the C terminal,
Based on this, the CPU 67 outputs a timing pulse to the piezoelectric buzzer 31 from its B terminal, and the piezoelectric buzzer 3
1 is activated.

The time-up time of the timer 68 is set to be sufficiently longer than the pause time during the handwriting operation when manually writing numbers, symbols, etc. that are input by handwriting in a plurality of writing operations. In other words, for example, the number "5" is written as "b" and "-"
If the time-up time of the timer 68 is set as described above, it will take only a short time from the writing of ``5'' until the writing of ``-'' starts. The piezoelectric buzzer 31 does not sound at a certain time, but starts sounding at an appropriate time after 95'' is completely written.

In other words, this piezoelectric buzzer 31 notifies the end of the input each time one number, symbol, etc. is input by hand, and waits until the piezoelectric buzzer 31 notifies the end of the input to proceed with the next number, symbol, etc. If you enter the information by hand, numbers and symbols, etc. that are input in one writing operation, as well as numbers and symbols, etc. that are input in multiple writing operations, will not be confused as input information for one character. can be entered.

On the other hand, the CP tJ 67 is configured to send numerical information and calculation command information to the calculation memory unit 69 based on the glyph pattern number input from the recognition calculation unit 62, and The information is sent to the display section 70 and displayed on the liquid crystal display element 18.

Further, the calculation memory unit 69 stores numerical information from the CP tJ 67 and executes calculations between the calculation number and the operand in accordance with calculation command information, and the calculation result is displayed on the display unit 1.
0 and displayed.

Next, the functions of the skip (SK) key 15, subsiefence (SB) key 16, and clear (C) key 17 provided on the outer surface of the computer main body will be explained.

The skip key 15 is operated when registering a standard glyph pattern in the registered standard pattern section 61. When the skip key 15 is pressed with the power switch/mode changeover switch 27 switched to the standard glyph pattern registration mode, the skip key 15 is pressed. , 0.1 is displayed on the display every time the skip key 15 is pressed once.
,2. ...9. +, -, X.

Numbers and operation symbols such as ÷, =, . . . are displayed sequentially.

For example, when the number "1" is written down with "1" displayed on the display section, the T-axis output and S-axis output of the T-axis signal output amplifier 53t and the S-axis signal output amplifier 53s are transferred from the data memory section 60. The combination of the T export power and the S export power at this time is sent to the registered standard pattern section 61.
Next, when the skip key 15 is pressed, the number "1" is registered as a standard glyph pattern.

Therefore, by pressing the skip key 15 and writing down the numbers and symbols while sequentially displaying them, the handwriting shape that matches the user's habits can be registered as a standard character shape pattern in the registered standard pattern section 61. I can do it.

The sub-sequence key 16 is pressed when a written character is misrecognized and a different number or symbol is displayed on the display. When this sub-sequence key 16 is pressed,
The recognition calculation unit 62 selects a glyph pattern with the next highest correlation to the glyph pattern selected first. Each time the subsequence key 16 is pressed, the glyph patterns are selected in descending order of correlation, and accordingly, the glyph pattern number input from the recognition calculation unit 62 to the CPU 67 is input again.

Therefore, the written character form is misrecognized and incorrect input information is c.
Even if information is input to the calculation memory section 69 from p U 67, the input information to the calculation memory section 69 can be corrected by pressing the sub-sequence key 16 until the same numbers or symbols as those entered by hand are displayed on the display section. can do.

In addition, the clear key 17 is used when clearing the previous calculation result,
This is pressed to clear the input when you input numbers or symbols by mistake.If you input the numbers or symbols by mistake, press this clear key 17 and then re-enter the numbers or symbols by hand. good.

In addition, when a written character shape is misrecognized as described above and a different number or symbol is displayed on the display, the misrecognition can be corrected by canceling the input using the clear key 17 and inputting it again. The user often has to decide whether to correct the misrecognition of a written character shape by operating the sub-sequence key 16 or by canceling the input using the clear key 17 and re-entering the input.

That is, this handwritten input type small electronic calculator identifies written numbers, operation symbols, etc. by the displacement of the writing shaft 46,
The data is input to the information processing unit to perform calculations, and when numbers, calculation symbols, etc. are written on the writing surface, calculations are automatically performed and the calculation results are displayed.

As described above, this handwriting input type small electronic calculator has a pair of leaf springs 52, 52 on the outside of the writing shaft 46, the base end of which is fixed inside the gripping case 10, and the tip of which comes into elastic contact with the outer periphery of the writing shaft 46. The pair of leaf springs 52, 52 are provided at substantially equal angles on both sides of the vertical line passing through the writing shaft 46 when the gripping case 10 is gripped diagonally to the writing surface with the predetermined side facing up. The pair of leaf springs 52 and 52 are provided at different positions, and mechanical deformation occurs in each of the pair of leaf springs 52 and 52 due to elastic deformation of the leaf springs 52 and 52 due to the displacement of the writing shaft 46, and the amount of mechanical deformation is electrically converted. A strain gauge of 50° C., 50S for converting the amount of change is attached, and the writing shaft 46 is placed on the side facing the pair of leaf springs 52.52 across the writing shaft 46. Auxiliary leaf spring 5 that presses and holds the writing shaft 46 in a neutral state
2a.

In this handwriting input type small electronic calculator, a strain gauge 50t detects the displacement of the writing shaft 46.

Since the strain gauges 50t and 50s are attached to leaf springs 52 and 52 that are brought into elastic contact with the writing shaft 46, and the strain gauges 50t and 50s are not brought into direct contact with the writing shaft 46, the writing shaft 4
To 6! Even if a blow is applied, this impact will cause strain gauge 5.
0t, 50s will not be destroyed, and the displacement of the writing shaft 46 can be detected using two strain gauges 50t.

The two strain gauges 50t are used as sensors for detecting the displacement of the writing shaft 46 because it can be done in only 50 seconds.

Since only 50s is required, a strain gauge of 50t is required.

Incorporation of 50s is also easy.

Moreover, this handwritten input type small electronic calculator uses a pair of leaf springs 52 to which strain gauges 50t and 50s are attached.
, 52 are provided at the above-mentioned positions, even when the grip case 10 is gripped in a position rotated in the circumferential direction from the correct grip position and a writing input is performed, both strain gauges 50t due to the displacement of the writing shaft 46 are , 50s has the same tendency as the deformation of both strain gauges sot , 50s when the gripping case 10 is held in the correct posture and a written input is made, and therefore, the two strain gauges 50t ,
Although the displacement of the writing shaft 46 is detected in only 50 seconds, there is no need to worry about misrecognizing the written character shape even when the grip case 10 is gripped in a position rotated in the circumferential direction from the correct gripping position and a handwritten input is performed. do not have.

In the above embodiment, the strain gauge is 50t.

Hold the leaf spring 52.52 with the 50s attached to the case 10.
The leaf springs 52, 52 The angle with respect to the vertical line may be in the range of about 30 to 60 degrees, and the plate springs 52 and 52 to which the strain gauges 50°C and 50S are attached are arranged so that the gripping case 10 is placed with the predetermined side up. Writing shaft 4 when gripped diagonally to the writing surface
It may be provided so as to be located below the center of 6. Further, in the above embodiment, the auxiliary leaf spring 52a is one piece, but
This auxiliary leaf spring 52a is a pair of leaf springs 52 to which strain gauges SOT and SOS are attached with the writing shaft 46 in between.
．． They may be provided at two locations so as to directly face each other.

In the above embodiment, the strain gauge is 50t.

The strain gauges 50t and 50s are attached to the outer surface of the leaf spring 52.52.
It may also be installed on the inner surface of the strain gauge 50t,
50s is not limited to a semiconductor strain gauge, and a strain gauge using metal foil or the like may be used.

Furthermore, in the above example, the strain gauge was 50°C.

Although a leaf spring is used as an elastic member for attaching the 50s and as an auxiliary elastic member for returning the writing shaft 46 to a neutral state, these elastic members may be made of an elastic resin plate such as polycarbonate. It is not limited to something like a ballpoint pen reflex reel, but may also be a simple shaft rod.

In the above embodiment, the Z-axis strain gauge 5 detects when axial writing pressure is applied to the writing shaft 46.
oz, but this Z-axis strain gauge 50z
It doesn't have to be there.

Furthermore, in the above embodiment, the writing shaft 46 is supported at its base end so that it can be tilted in either direction, but if the writing shaft 46 is made flexible, the writing shaft 46
The base end of 6 may be fixed within the grip case 10.

Although the above embodiment has been explained by taking as an example a writing data input device incorporated into a small handwriting input type electronic calculator, the present invention is also applicable to a writing data input device that is connected to a personal computer and is equipped with only a writing input section. The present invention can also be applied to a writing type data input device for inputting data to a computer.

〔Effect of the invention〕

According to this invention, when a pair of elastic members to which strain gauges are attached are held diagonally to a writing surface with a predetermined side up, the pair of elastic members are placed approximately on both sides of the vertical line passing through the writing axis. Since the positions are shifted by equal angles, even if the gripping case is gripped in a circumferentially rotated position from the correct gripping position and a writing input is performed, both strain gauges will not be deformed due to writing or axis displacement. In this case, the deformation is the same as that of both strain gauges when writing is performed while gripping the gripping case in the correct posture.Therefore, the displacement of the writing shaft 46 is detected using only two strain gauges. However, even if the grip case is held in a position rotated in the circumferential direction from the correct grip position and a handwritten input is made, there is no fear that the handwritten character shape will be misrecognized.

[Brief explanation of drawings]

1 to 10 show an embodiment of the present invention, in which FIG. 1 is a perspective view of a displacement detection section of a writing shaft, FIG. 2 is an external perspective view of a small electronic calculator with writing input, Figure 3 is an enlarged sectional view taken along line A-A in Figure 2, Figures 4 and 5 are
Figure 6 is an enlarged perspective view of the base member at the tip of the case, Figure 7 is a usage state of the handwriting input type small electronic calculator, Figure 8 is an enlarged sectional view taken along lines B-B and C-C in the figure. Figure 9 is a circuit diagram of a handwritten input type small electronic calculator, Figure 9 is an output waveform diagram when the number "1" and subtraction symbol "-" are input by hand while gripping the gripping case in the correct posture, and Figure 10 is a diagram of the gripping case. It is an output waveform diagram when the number "1" and the subtraction symbol "-" are input by hand while gripping the case in an orientation rotated in the circumferential direction from the correct gripping orientation. FIG. 11 is a perspective view of a writing shaft displacement detection section of a writing data input device that the applicant had considered before this invention, FIG. 12 is a resistance change characteristic diagram of a strain gauge, and FIG. Figure 14 is an output waveform diagram when the numeral "1" and the subtraction symbol "-" are input by hand with the grip case held in the correct posture using the writing data input device shown in Figure 11. It is an output waveform diagram when the gripping case is gripped in a position rotated in the circumferential direction from the correct gripping posture and the number "1 pa" and the subtraction symbol "-" are input by hand. 10...Gripping case, 46... Writing shaft, 50t,
50s...strain gauge, 52...plate spring, 52
a... Auxiliary leaf spring. Applicant's agent Patent attorney Takehiko Suzue Figure 11 Figure 12

Claims (1)

[Claims] A writing shaft is provided with the tip protruding inside the grip case, and the tip side is displaced in a direction opposite to the writing direction as a writing operation is performed by pressing the tip against the writing surface, and the displacement of this writing shaft is detected. In the writing type data input device, the writing type data input device is provided with a means for recognizing a written character shape and inputting the data to an information processing unit, the base end being fixed in a gripping case on the outside of the writing shaft, and the outer periphery of the writing shaft at the distal end. A pair of elastic members are provided that come into elastic contact with the writing surface, and the pair of elastic members are arranged such that when the grip case is held obliquely to the writing surface with a predetermined side facing up, the grip case is placed on both sides of the vertical line passing through the writing axis. The pair of elastic members are provided so that they are shifted by approximately equal angles, and mechanical deformation occurs in each of the pair of elastic members due to the elastic deformation of the elastic member due to the displacement of the writing shaft, and the amount of mechanical deformation is expressed as the amount of electrical change. At least a strain gauge for converting the writing shaft is attached to the side opposite to the pair of elastic members across the writing shaft, and the writing shaft is held in a neutral state by pressing the writing shaft against the pair of elastic members. A writing type data input device characterized in that one auxiliary elastic member is provided.