JPS5816441B2 - electronic scale - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention adds an angle measurement function to an electronic scale and displays the measured angle on a display section via an electronic circuit, thereby expanding the range of uses of the electronic scale and streamlining measurement work. The purpose is to improve work efficiency.

Generally, an electronic scale pulls out one end of a sliding scale set in a spiral shape on the main body, and automatically measures the amount of pull out, thereby displaying digital information or printing on a display section via an electronic circuit.

In conventional measurement work, separate measuring instruments have been used for angle measurement and length measurement.

That is, a protractor was generally used to measure angles, and an electronic scale was generally used to measure lengths.

Therefore, if angle measurement and length measurement are required in measurement work, two types of measuring instruments must be prepared.In addition, with conventional protractors, it is necessary to visually read the scale in order to obtain measurement results, resulting in misreading. Human errors such as these were easy to occur, and it was extremely difficult to decipher fine scale marks.

On the other hand, with electronic scales, the measured length is directly displayed on the display, so there is no need to visually read the measurement scale, and the work efficiency is extremely high when measuring length.

The present invention applies the characteristics of this electronic scale to the field of angle measurement work, and by making full use of technical means, adds an angle measurement function in addition to the length measurement function, so that length and angle can be measured with one measuring instrument. To provide an electronic scale that can perform measurements and directly display measurement results on a display unit.

The present invention will be explained in detail below using the drawings.

FIG. 1 is an external perspective view of an electronic scale that is an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the mechanical parts of the electronic scale in FIG. 1.

3 and 4 are block diagrams of electronic circuits as one embodiment of the present invention.

FIG. 5 is a time chart diagram of the electronic circuit in FIG.

A part of the bottom of the lower case 1 is made of a transparent member such as glass or plastic, and a measurement reference line 2 is installed therein.

A lower bearing 3 is provided at a portion of the measuring reference line 2 corresponding to the measuring origin, and rotatably supports the winding spool 5 of the measuring slide 4.

The spool 5 consists of a shaft portion and flange portions located at both ends of the shaft portion, and a measuring slide 4 is wound around the shaft portion.

The measurement slide-in 4 has a locking portion 6 such that one end thereof always protrudes outward from the main body when the measurement slide-in 4 is mounted on the main body.
The spool 5 rotates in conjunction with the movement of.

The center portion of the spool 5 is made of the aforementioned transparent member and is formed to be transparent in the axial direction, and an angle measurement index 7 is engraved on the transparent member forming portion.

One flange portion of the spool 5 is located between the light emitting and receiving devices of the optical sensor 8, and the amount of rotation of the spool 5 is detected by the optical sensor 8 by slit processing or the like.

Further, a spring body 9 such as a mainspring is interposed between the lower bearing 3 and the spool 5, and provides the spool 5 with a reversing return force for rewinding the measuring slide-in 4.

Furthermore, the main body is assembled by attaching the upper case 10 to the lower case 1.

The upper case 10 has a similar transparent member in a region corresponding to the transparent member forming region of the lower case 1, and supports the spool 5 rotatably from the upper direction by an upper bearing 11.

A display window 12 of the display section and a mounting hole 14 for a changeover switch 13 are formed on the upper surface of the upper case 10, and a cutout for taking out the measuring slide 4 is formed at the joint between the upper case 9 and the lower case 1. 15 have been processed.

That is, the locking portion 6 of the measuring slide-in 4 is properly locked at this notch portion 15 .

In addition to the above, an electronic circuit and a display unit connected to the optical sensor 8 and the changeover switch 13 are built into the main body cases 1 and 10.

In the electronic scale having the above configuration, when measuring an angle, it is performed in the following manner.

That is, the changeover switch 13 is set for angle measurement, the measurement reference line 2 installed on the lower case 1 is aligned with one of the measurement angle forming lines, and the measurement slide 4 is pulled out to rotate the spool 5. 5 is aligned with the other of the measurement angle forming lines.

The optical sensor 7 detects the amount of movement of the measurement index 7 from the measurement reference line 2 at this time via the amount of rotation of the spool 5,
The detected amount is replaced with an electrical pulse signal and input to the electronic circuit shown in FIG.

The measurement indicator 7 overlaps the measurement reference line 2 when the measurement slide-in 4 is not pulled out, forming a reference state before measurement.

The block diagram of FIG. 3 is a block diagram of a circuit for discriminating between a count-up signal and a count-down signal.

The optical sensor 8 is composed of a sensor S1 and a sensor S2 whose phases are shifted by 90 degrees from each other.

Each sensor S1. The signal at S2 is supplied to amplifier W1. Amplified via W2 and inverter ■1. By arranging V2, signals A, A and B, B are output respectively.

FIG. 5 shows a time chart of these signals.

FIG. 5A shows a time chart during count-up, and FIG. 5B shows a time chart during count-down.

Count up signal and count down signal are on spool 5
FF - FF8 is determined by the forward and reverse rotation direction of D
There is 1 in the type flippfamp circuit.

During count-up, the A signal leads the B signal by 90 degrees in phase, so the D-type flip-flop FF1 is set at the rise of the B signal when the A signal is at H level.

FF2 is set at the rising edge of the clock φ after FF1 is set, and its output passes through an OR gate and becomes the up input of the 360-decimal up-down counter 16 and the decimal up-down counter 17 shown in FIG.

Also, when FF2 is set, FF1 is simultaneously reset by this output.

Similarly, the output of FF4 is up/down counter 16.
, 17 is the up input.

Therefore, an X signal as an up input is generated from the <OR gate as shown in FIG. 5A.

During countdown, the B signal leads the A signal by 90 degrees in phase.

Therefore, using the same principle as above, the Y signal as a down input is inputted to the up/down counters 16 and 17 from the <OR gate shown in FIG. 5B.

The 360-decimal up-down counter 16 electronically counts the measured angle in synchronization with the X signal or Y signal corresponding to the rotation of the spool.

Further, the decimal up-down counter electronically counts the amount of rotation of the spool 15 in the same manner.

The count result in the 360-decimal up-down counter 16 is sent to a display changing circuit 18.

During angle measurement, since the changeover switch 13 is set for angle measurement, the display switching circuit 18 selects and outputs the count result of the 360-decimal up-down counter 16, and displays the result on the display section 20 via the display drive circuit 19.
The measured angle is displayed digitally.

When measuring the length of the object to be measured, switch 13
Set for length measurement.

Furthermore, the measuring slide 4 is pulled out, the 0 scale is aligned with one end of the measurement length of the object to be measured, and the measuring slide 4 is pulled out by an amount corresponding to the measurement length.

At this time, the optical sensor 8 detects the amount of rotation of the spool 5 that is linked to the measuring operation of the measuring slide-in 4, and as described above, the detected amount is replaced with an electrical pulse signal and sent via the discrimination circuit shown in FIG. and input it to the up/down counters 16 and 17.

The measured length is electronically counted by a decimal up-down counter 17, and the count result is corrected by a multiplying circuit, a square circuit, a multiplying circuit by L, and a subtracting circuit, and then inputted to a display switching circuit 18.

By pulling out the measuring slide 4 wound around the shaft of the spool 15, the number of turns of the measuring slide 4 on the shaft decreases, that is, the radius of the winding portion of the measuring slide 4 decreases. As the amount of pullout of the measuring slide 4 increases, the amount of rotation of the spool 5 relative to the amount of pullout increases.

Since the decimal up-down counter 17 performs electronic counting in response to the amount of rotation of the spool 5, it is necessary to correct the count result to match the amount of withdrawal of the measuring slide 4.Here, lo = from the beginning of the tape. Length to the end r Radius of the tape wound on the varnish spool (radius from the center of the spool to the outermost tape) S: Length of the tape pulled out θ: Spool when the tape is pulled out by length S Rotation angle (radian) θ1: Tape length l.

Just pull out. The rotation angle of the spool (in radians) when to: Tape thickness ro The radius and slip of the spool are expressed as follows, and the length lo from the starting end to the end of the tape is expressed by the following formula.

If the scale is now pulled out by a length S, then the spool has l.

-8 length of tape is wrapped.

Letting the winding angle at this time be θ2, then becomes.

Therefore, θ1 and θ2 are expressed as θ1 and θ2.

On the other hand, when the length S is pulled out, the rotation angle of the reference point is θ
Since it is expressed as 1-θ2, θ is expressed by the following equation.

Using equation (1) to find the length S using θ as a parameter, we get Now, if m detection holes are provided in the spool, 2π The rotation angle per detection hole is - (radian).

Therefore, when the spool rotates when the tape is pulled out, and the number of output pulses detected by the detection sensor is 2πnn, then θ-□, and eliminating θ from the above equation (2) becomes the following equation.

In (3) above, each constant term is Then, the above equation (3) becomes the following equation.

5-Kn-Ln2 Therefore, by making the correction shown by Kn-Ln2, the count result and the amount of withdrawal of the measurement slip-in (tape) 4 match.

The aforementioned doubler circuit, squarer circuit, L-multiplier circuit, and subtraction circuit are circuits for performing this correction.

Since the changeover switch 13 is set for length measurement, the changeover circuit 18 selects and outputs the corrected count result from the decimal up-down counter 17, and displays it on the display unit 20 via the display drive circuit 19. The measured length is displayed digitally.

If the 360-decimal up-down counter 16 is set to 180-decimal or 90-decimal, it becomes possible to measure every 180 degrees or every 90 degrees.

This can be selected appropriately depending on the purpose of use.

It is also possible to install a plurality of these counters and use them selectively with a changeover switch.

The unit of angle can be converted not only to degrees but also to radians and gradians by adding an arithmetic circuit that calculates the count results of the 360-decimal up-down counter 16. Also, by providing a unit switching circuit, these various units can be converted. It is also possible to switch the display.

By implementing the present invention, it is no longer necessary to prepare two types of measuring instruments, an angle measuring device and a length measuring device, in measurement work, and angle measurement and length measurement can be realized with a single electronic scale of the present invention.

Furthermore, since all measurement results are directly displayed on the display, the measurement results are easy to read, and human errors such as misreading errors can be very effectively prevented.

Furthermore, in cases where a certain measurement length is to be given on an object to be measured and the measurement length is required at a position having a certain angle from the reference position, the present invention provides a very effective means. As described above, the present invention opens up a new field of use for electronic scales by adding an angle measurement function with a simple structure and operation without impairing the functions of conventional electronic scales, streamlining measurement work and improving work efficiency. has been achieved.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of an electronic scale that is an embodiment of the present invention. FIG. 2 is an exploded perspective view of the mechanical parts of the electronic scale in FIG. 1. FIGS. 3 and 4 are block diagrams showing electronic circuits as one embodiment of the present invention. FIG. 5A is a time chart when the electronic circuit in FIG. 3 receives an up-count signal. FIG. 5B is a time chart when the electronic circuit in FIG. 3 receives a down count signal. 1... Lower case, 2... Measurement reference line, 4...
Measuring slip-in, 5... Spool, 7... Measuring indicator,
8... Optical sensor, 10... Upper case, 13.
. . . Changeover switch, 16. 360 decimal up-down counter, 17. decimal up-down counter, 18. Display switching circuit, 20. Display section.

Claims (1)

[Claims] 1. A measuring slide set stored in the main body case, a rotating body that is linked to the pull-out and rewinding operations of the slide, a rotation amount detection means for the rotation body, and a rotation amount detection signal from the rotation amount detection means. An electronic scale having a display unit that electronically counts through an electronic circuit and displays the measured length of the sliding scale, an angle measurement index linked to the rotation of the rotating body and an angle measurement reference for the index. An angle detection mechanism is constructed by providing a position, the angle measurement index and the angle measurement reference position are configured to be transparently confirmed from the outside of the main body case, and the electronic circuit is switched to electronic counting of the measurement angle, and the angle measurement reference position is An electronic scale comprising a changeover switch for displaying the measurement angle on a display section.