JPS588448B2 - Oscillating flowmeter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a display device for an oscillating flowmeter that measures a flow rate by electrically converting and displaying the displacement of a movable member provided in a flow path.

Conventionally, regarding this type of flowmeter, the inventor has already published Japanese Patent Application Laid-open No. 51-94270 (electrical display), and
JP-A-51-106464 (mechanically displayed)
However, since each of these is formed to be displayed over the entire swing range of the movable member, there is an inconvenience that an error occurs at a small flow rate.

The purpose of this invention is to eliminate such inconveniences in devices that electrically display flow rates.The purpose of this invention is to prevent the flow rate from being measured when the swing angle of the swinging movable member is below a certain angle. It is characterized by:

The invention will be explained in detail with reference to the following figures.

FIG. 1 is a partially sectional side view of a device for converting and displaying the displacement of a movable member in an oscillating flowmeter according to the present invention, where 52 is a flow path and the fluid flows in the direction of the arrow (to the left). flows.

Reference numeral 1 denotes a resistor consisting of a resistance plate 2 (see FIG. 2) and a rod-shaped arm 3, which is a movable member and is formed to almost cover the flow path 52, and is a part of the case 50 provided above the flow path 52. It is attached to the first shaft 5 provided in the.

6 is a shaft 5 of the rod-shaped arm 3 so as to rotate together with the movable member 1;
One end 7a of a connecting rod 7 is pin-coupled to the surface of the gear 6.

The other end 7b of the rod 7 is pin-coupled to a part of a sector gear 8, which will be described later, and is formed so as to rotate the sector gear 8 in the same direction as the gear 6 rotates. .

The symbol 55 on the right shoulder of the movable member 1 is a potentiometer used to convert the rotational displacement of the movable member 1 into an electrical quantity and transmit it to a remote location, and the rotation of the gear 6 is controlled by the gear 5.
4 and is transmitted to the potentiometer 55.

This remote display method is explained in FIG.

The sector-shaped gear 8 is attached to a second shaft 9 provided in the case 50, and the sector-shaped gear 8 is connected to a gear 1 for the proportional cam 11 described later.
It is set to mesh with 5.

Further, a sector-shaped cam 10 is fixed to the sector-shaped gear 8.

When the movable member 1 is in the illustrated position (as well as in the slightly rotated position), an actuator mechanism is provided on one straight portion 10S of the fan-shaped cam 10, which has the tendency to close a microswitch 28 provided nearby. The switch 28 is in contact with the switch 29 to open the switch 28 against the above-mentioned behavior.

A proportional cam gear 15 on the main mover 12 side of the proportional cam 11, which will be described later, is attached to a third shaft 16 provided in the case 50, and a concave cam 17 is fixed to the gear 15.

When the movable member 1 rotates by more than a certain angle (approximately 30 degrees), the sector gear 8 and the gear 15 are disengaged, the sector cam 10 and the concave surface of the concave cam 17 engage, and the movable member 1
This prevents rotation from being transmitted to gear 15 even if the gear rotates over a certain angle, protects the equipment, and prevents flow errors at high flow rates. Gear 15 is meshed at the correct position to prevent measurement errors.

The proportional cam 11 is a main drive element 1 with a cam surface that rolls into contact.
2 and a follower 13, and is formed so that the angle of movement of the follower 13, which moves following the movement of the main mover 12, is a linear movement in proportion to the flow rate (for details, see JP-A-51 (Refer to No. 106464) g The main driver 12 is fixed to the proportional cam gear 15 and is rotatably mounted around the third shaft 16.

Further, the follower 13 is formed so that its cam surface contacts the cam surface of the main driver 12 to rotate, and is attached to a fourth shaft 18 provided in the case 50.

Further, the leading ends of the main mover 12 and the follower 13 are connected by springs 14, respectively, so that the main mover 12 and the follower 13 are constantly in contact with each other and swing together.

The first arm 19 that is integral with the follower 13 and extends downward is the mouth-ra 2.
0, and is inserted between and engaged with disc-shaped protrusions 32a and 32b provided at the left end of the driven shaft 31, which will be described later.

The driven shaft 31 is a shaft that does not rotate but moves laterally, and a friction wheel 33 that comes into contact with a rotating disk 35 of a second motor (constant speed motor) 36 is fixed near the center, and the right end is connected through a slide joint 34. It is connected to a crank-shaped shaft 37 of a worm 38 that rotates an integration display meter 48, which will be described later.

Note that a part of the first arm 19, the roller 20, the friction transmission part (33.35), the driven shaft 31, the worm 38, the worm gear 39, etc. are coated with light oil to prevent errors caused by dust in the air. It is housed in an oil bath 40.

A second arm 21 extending above the fourth shaft 18 of the follower 13 is formed to swing integrally with the first arm 19, and is connected to an arm 23 of a pen holder 24 via a joint 22.

Reference numeral 25 is a pen, and 26 is a roll of recording paper.

Further, the recording paper 26 is configured to be fed at a constant speed by a No. 2 motor 27.

Therefore, as long as the paper 26 is being fed, the flow rate will be continuously recorded on the paper 365 days a year.

The reference numeral 48 is a flow rate integration display meter, and the rotation of the worm wheel 39 is displayed after being subtracted by a fixed number of rotations by a differential gear mechanism 41, which will be described later.

A worm wheel 39 that meshes with the worm 38 is integral with the first gear 42 located above.

Further, the first gear 42 and the second gear 43 are connected to the intermediate gear 4.
They are engaged through 4.

The intermediate gear 44 is rotatably mounted on the large gear 45 and rotates planetarily around the first and second gears 42 and 43.

Reference numeral 47 is a third motor that rotates a small gear 46 that meshes with the large gear.

The rotation of the gear 43 of the integration indicator 48 is caused by the center 0 of the friction wheel 33 fixed to the driven shaft 31 and the rotating disk 35.
The differential gear mechanism 41 is formed such that the rotational speed of the worm wheel 39 is subtracted from the rotational speed of the worm wheel 39 by a rotational speed commensurate with the rotation of the driven shaft caused by shifting the driven shaft by d.

A case 50 mounted on the flow path 52 is formed to cover all the equipment except the movable member 1, and a protective cover 5 is further provided on the upper side of the case 50 to block direct sunlight.
1 is attached so that it can be opened and closed.

Portions 50a and sob on the ceiling of the case 50 are glass windows for viewing the recording paper 26 and the totalizer 48.

FIG. 3 is a circuit diagram showing the relationship between the first, second and third motors and the power source in FIG. 1, in which the main switch SW and the first motor 27 are connected in series to the power source G; A circuit branched from between the original switch SW and the first motor 27 connects the second motor 36 and the third
A motor 47 is connected in parallel.

FIG. 4 is a block diagram illustrating a method of converting the rotational displacement of the movable member shown in FIG. 1 into an electrical quantity using the potentiometer 55 and displaying the electrical quantity remotely.

The reference numeral 55 is a potentiometer in which the rotation of the movable member 1 is increased by a speed increasing gear 54 as shown in FIG.

56 is an amplifier.

The top (A) system in this system is talk counter 6.
57 is a V/Pi conversion unit (output voltage vs. frequency) in a system connected to a daily counter 61 that can be reset to 0 and zero.
, 58 is a frequency divider, and 59 is a counter drive circuit.

The next system is connected to the pen recorder, 62 indicates the pen recorder output section, and 63 indicates the pen recorder.

The next system (or) is a system for detecting an abnormality in the output voltage, 64 is an abnormal voltage detector, and when an abnormal voltage is detected, a lamp 65 is turned on to stop the pen recorder, and
The talk counter 60 and the daily counter 61 are coupled so that they can be stopped.

The next system (d) is a system to know the flow rate based on current changes, and 66 is a V/I converter (output voltage vs. output current).
, and 67 is an outlet for a measuring device that indicates flow rate by ampere change.

The next system (e) is a system for determining the flow rate based on voltage changes, with 68 being an amplifier and 69 being an outlet for a measuring device that indicates the flow rate based on voltage changes.

Note that the reference numeral 28 shown in the upper left is a microswitch that opens the circuit when the vibration of the movable member 1 is small, and controls the frequency divider 58 of the (A) system and the pen recorder 62 of the (A) system, respectively. inserted into the circuit.

The present invention is constructed as described above, and as shown in FIG. 1, when the fluid in the flow path 52 is not flowing, the movable member 1 rests against the bottom of the flow path.

Further, in FIG. 3, when the main switch SW is closed, the first motor 27 of the pen recording device rotates.

Therefore, the recording paper 26 rotates, and the zero position of the flow rate is recorded by the pen 25.

However, the second motor 36 for the rotating disk, and the differential gear mechanism 41
The third motor 47 is stopped.

Therefore, the integration display meter 48 does not operate.

When the fluid starts to flow, the movable member 1 swings in the direction of the arrow, the gear 6 rotates clockwise, and the connecting rod 7 is pulled downward, causing the sector gear 8 connected thereto and the The integral fan-shaped cam 10 also rotates clockwise.

Therefore, the proportional cam gear 15 meshing with the sector gear 8
In addition, a main rotor integrated therewith rotates counterclockwise (upward) about the third shaft 16.

Note that the rotation of the fan-shaped cam 10 causes the microswitch 28 to
As can be seen from FIG. 3, the second motor 36 of the rotating disk 35 and the third motor 47 of the differential gear mechanism 41 are closed.
rotates.

Now, when the main mover 12 rotates, the follower 13 that comes into contact with and follows it also rotates clockwise around the fourth shaft 18, and the second arm 21 that is integrally fixed to the follower 13 rotates clockwise. rotates clockwise.

Therefore, the arm 23 that is pin-coupled with this is moved to the right,
As a result, a curve corresponding to the flow rate is drawn on the recording paper 26 by the pen 25 over time.

Further, since the first arm 19 extending downward from the follower also rotates clockwise, it is connected to the driven shaft 31 which is engaged by the roller 20.
moves to the left and rotates in proportion to the distance moved from the center 0 of the rotating disk 35.

The totalizing display meter 48 displays the amount of movement, that is, the number of revolutions according to the flow rate, and it is known that this is cumulative.
Since it is explained in detail in No. 106464, it will be omitted here.

At this time, in the embodiment of the present invention, in order to prevent the friction wheel 33 from slipping near the center 0 of the rotating disk 35, the friction wheel 33 is
Since the initial point of 3 is shifted by d from the center 0, the rotation corresponding to this d is subtracted from the rotation speed of the worm wheel 39 by the differential gear mechanism 41, and the rotation speed corresponding to the correct flow rate is displayed on the integration display meter 48. will be displayed.

Also, if the movable member 1 swings by more than a certain angle (30° in this case) for some reason, the fan-shaped cam 10 and the concave cam 17
When the movable member 1 returns to a small angle of deflection, the sector gear 8 and gear 15 are in the correct meshing position. No return weighing errors occur.

When the fluid flow stops, the movable member 1 returns to its original position as shown in FIG. 1, and the proportional cam 11 also returns to its original position due to the spring 14.

Further, the friction wheel 33 of the driven shaft 31 also returns to a position shifted by d from the center 0 of the rotating disk 35, and the rotation is not integrated on the display meter 48.

Next, an electrical display method for transmitting the signal to a remote location will be explained. When the movable member 1 swings, the rotation is transmitted to the potentiometer 55 and amplified by the amplifier 56.

When the movable member 1 is oscillating over a certain angle,
Since the microswitch 28 is closed and the frequency divider 58 and pen recorder output section 62 are in operation, the output of the potentiometer 55 amplified by the amplifier 56 is converted to a frequency by the V/F conversion section 57 in the (a) system. is roughly divided into a low frequency by a frequency divider 58, and is transmitted to a talk counter 60 and a daily count 61 that can be returned to zero via a counter drive circuit 59, and the flow rate is displayed on both counters. .

At the same time, in the (mouth) system, the output of the potentiometer 55 drives a pen recorder 63 via a pen recorder output section 62 to record the flow rate on recording paper.

If the potentiometer 55 malfunctions and an abnormal voltage occurs, the abnormality detector 64 is activated in the (c) system, the alarm lamp 65 lights up, and the pen recorder, the talk counter 60, and the daily counter 61 are activated. to prevent incorrect display.

In addition, in the (d) and (e) systems, the ■/■ converter 66
Outlet to equipment powered by amperage input through 6
7 is also provided with an outlet 69 for a device operated by volt input via an amplifier 68, so that the flow rate can be detected remotely electrically by connecting the appropriate device.

In this invention, as explained above, the totalizer does not operate where the movable member is slightly displaced, so even if the movable member stops at a position where the movable member is slightly displaced due to dirt in the flowing water, etc. Never measure as if there is a flow.

Therefore, it can be used as a flowmeter in places where garbage and the like flow, such as drainage channels, to achieve special effects.

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view of an embodiment of a flowmeter according to the present invention, FIG. 2 is a partial plan view of the same embodiment, FIG. 3 is an electric circuit diagram of the same embodiment, and FIG. The figure is a workflow diagram of a method for electrically converting the displacement of a movable member using a potentiometer in the same embodiment as described above and displaying the same electrically. DESCRIPTION OF SYMBOLS 1... Movable member, 11... Proportional cam, 27... First motor, 33... Friction wheel, 35... Rotating disk, 36... Second
Motor, 40... Oil bath, 41... Differential gear mechanism, 48... Integration display meter, 50... Case, 51... Case
Scover, 55...Potentiometer, 57...V/F
i conversion unit, 58... frequency divider, 59... counter drive circuit,
62...Record output generator, 64...Abnormal voltage detector, 6
6...V/I converter.

Claims (1)

[Claims] 1. The output of a potentiometer 55 that generates an output voltage proportional to the flow rate by angular displacement due to the flow pressure received by a movable member provided in the flow path, and a V/F converter 57 that converts the output voltage of the potentiometer into a frequency. A counter drive circuit 59 for input, and a recording output unit 62 parallel to the counter drive circuit 59,
A converter 66 that converts an output voltage into an output current, and a switch means 28 that cuts off output from the counter drive circuit and the recording output section when the angular displacement of the movable member is smaller than a predetermined amount. An electrical display device for an oscillating flowmeter.