JP3147390B2 - Elliptical vibration detection method of vibration feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting an elliptical vibration used for measuring the amplitude and the angle of the elliptical vibration of a trough of a vibration feeder using a vibration motor as a vibration source.

FIG. 7 shows a resonance type vibration feeder 1 using a vibration motor as an excitation source. As is well known, a trough 2 is suspended on a part 6 of a building by a pair of coil springs 4 and 5. Have been. A pair of wing plates 3 are attached to the bottom wall of the trough 2, and a pair of attachment plates 7a and 7b are fixed to the ends thereof. , 8b are fixed. This rubber plate 8
The other surfaces of a and 8b are fixed to the casing surface of the vibration motor 9. The casing 9 has a built-in vibration motor M, and semicircular unbalance weights 11 are fixed to both ends of the rotating shaft 10. The vibration feeder 1 using a conventionally known resonance type vibration motor M as a vibration source is configured as described above. When the vibration motor M is driven, the unbalance weights fixed to both ends of the rotating shaft 10 are driven. The rotation of 11 generates a centrifugal force, which is a circular excitation force, which is caused by plate rubbers 8a, 8b and mounting plates 7a, 7a.
b is transmitted to trough 2 through trough 2
Total mass m of the movable part consisting of the wings 3 and a pair of plate rubbers 8
From the total spring constant K of the elastic means consisting of a and 8b, √K / √
m at a frequency close to the resonance frequency determined by m
Is driven, the trough 2 performs a resonance vibration. Such a vibration force causes the trough 2 to perform an elliptical vibration with a locus V (shown exaggeratedly). As shown in FIG. 8, this elliptical vibration V has an elliptical shape having a major axis A on an axis XX substantially parallel to the shearing direction of the plate rubbers 8a and 8b, and a minor axis B in a direction perpendicular thereto. The inclination angle of the amplitude A with respect to the horizontal line x-axis in the major axis direction, that is, the vibration angle θ is substantially determined by the mounting angle of the plate rubbers 8a and 8b. When it is desired to know the amplitude A on the axis and the amplitude B on the short axis, conventionally, an amplitude nameplate 21 as shown in FIG. 9 is used, which is made of a rectangular paper 22 as shown in FIG. Is coated with an adhesive, and graduation lines 23 are printed at regular intervals on the surface thereof.
Display lines 24a and 24b are printed on both sides of the display. When the amplitude of the vibrating body 200 is measured with the amplitude nameplate 21 as described above, the vibration direction is adjusted so as to match the scale line 23, and the vibrating body 200 is attached to the surface of the vibrating body 200. Now, if the vibrating body 200 performs a linear vibration in the direction a as shown in FIG. 10, the pair of display lines 24a and 24b vibrate in this direction at the width of the amplitude, and thus, the display line 24a and 24b P and Q are observed as an afterimage, these composite portion is exhibited rhombic shape, observing the scale 23 in the distal end a, whereby it is to measure Fuhaba of the vibrator 200, the vibration feeder linear If vibration is applied, accurate measurement can be made by sticking the amplitude nameplate 21 such that the scale line 23 matches the vibration direction.

However, an elliptical vibration V as shown in FIG.
When measuring the amplitude in the major axis direction of the trough 2 for performing the
Even if 1 is attached to the trough 2, vibration in the short axis direction is applied, so that the entire graduation line 23 also has a band as a residual image of a certain width, and these composite residual images become considerably complicated, and in the case of linear vibration, Cannot accurately determine the intersection A of the afterimage. The Rukoto align your Fuhaba nameplate in the axial direction of the elliptical vibration V even difficult. Conventionally, in spite of such difficulties, the amplitude in the long axis direction has been measured with such a nameplate based on the experience of the measurer.

In some cases, it is desired to measure the vibration angle of the resonance type vibration feeder 1, that is, the vibration angle θ with respect to the long axis XX, for example, the horizontal x axis. In such a case, a so-called angle nameplate 31 as shown in FIG. 11 is used, which is also coated with an adhesive on the back surface similarly to the amplitude nameplate 21, but has a surface close to a semicircular line 32. .. Are printed at the ends of the display lines 33 so that 90 degrees extend from the center.
As shown in FIG. 12, such an angle name plate 31 is attached to the side of the trough 2 of the vibrating feeder 1 so that the X′-X ′ direction is
Is adhered so as to be parallel to the bottom surface, that is, in a horizontal plane.
On this, each scale display line 33 is reflected as an afterimage as a band having a certain width due to vibration. Among these, the scale line 33 which is the band with the smallest width is read, and the vibration angle θ is determined by this scale. I try to measure. Even when the vibration angle is measured using such an angle name plate 31, in the case of linear vibration, it can be measured almost exactly, but in the case of elliptical vibration V, how precisely the trough 2 is adjusted. However, even if the display line 33 is adhered to, due to the vibration B in the short axis direction, all the display lines 33 appear as afterimages having a width, and the display line 33 having the smallest width among these display lines 33 is read. However, this is often due to the experience of the measurer, and generally the measurement is very difficult.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and even a measurer who has no experience in measuring such vibrations can accurately measure the vibration in the major axis direction of the elliptical vibration. It is an object of the present invention to provide a method for detecting an elliptical vibration capable of accurately measuring a width and a vibration width in a short axis direction and a vibration angle of a vibration in a long axis.

[0006]

Further objects Means for Solving the problems] The first vibrating off the vibration detecting element for detecting the vibration of the first predetermined direction
A second vibration detecting element mounted on a surface parallel to the vibration direction of the feeder and detecting a vibration in a second predetermined direction perpendicular to the first predetermined direction on a surface parallel to the vibration direction of the vibration feeder ; Mounting the first vibration detecting element and the second vibration detecting element
Said detection output and the phase difference φ of these detection output of the vibration detecting element, the first Fuhaba the long axis direction of the elliptical vibration of the vibrating feeder by calculation, the second Fuhaba and the long axis direction of the short axis direction The elliptical vibration detection method is characterized in that a vibration angle θ with respect to a first predetermined direction is obtained.

[0007]

[Effect] Generally, the equation of elliptical vibration is x = a in rectangular coordinates.
sin ωt and y = b sin (ωt + φ). From the detection outputs of the first and second vibration detecting elements in the x-axis direction and the y-axis direction, a, b, and φ are obtained. From these measured values, the amplitude A in the major axis direction in the vibration direction (long axis), the amplitude B in the short axis direction in the direction perpendicular to the major axis (short axis), and the predetermined direction with the amplitude A (x-axis direction) Is calculated by a computer. Since the measurer does not need any experience and only needs to attach the first and second detecting elements, for example, the casing to the vibrating surface of the vibrating feeder in any direction, the measurement can be performed very easily and accurately. it can.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a method for detecting an elliptical vibration according to the present invention;

First, the electric circuit will be described with reference to FIG. In FIG. 1, the vibration detector 40 has a shape as shown in FIG. 3, and as will be described later, it incorporates detection elements 40a and 40b, and these detection outputs are supplied to low-pass filters 41a and 41b, respectively. Here, high-cycle signal components such as noise are removed, and this output is supplied to amplifiers 42a and 42b. The amplified output is supplied to A / D converters 43a and 43b to convert an analog value into a digital value, and this digital value is supplied to a computer 45. Computer 4
5 are further provided with low-pass filters 41a and 41 on the input terminal side.
The phase difference detector 44 receiving the output of b is connected.
In the computer 45, A / D converters 43a and 43b
A predetermined operation is performed in response to the digital output from the controller and the output of the phase difference detector 44.
7, 48, and 49.

That is, the amplitude of the elliptical vibration V in the long axis direction is displayed on the long axis LCD display section 47 by a computer 45 using an arithmetic expression described later, and the amplitude of the elliptical vibration V in the short axis direction is displayed on the short axis LCD. It is displayed on the display unit 48. The vibration angle LCD display unit 49 is also configured to display a vibration angle with respect to a certain axis, that is, a tilt angle θ of the long axis with respect to the horizontal direction, which is calculated by the computer 45 in the same manner.

Next, the details of the vibration detector 40 will be described with reference to FIG. This is an almost cylindrical casing 5
The first and second force detecting elements 40 a and 40 b made of, for example, lead zirconate are held on the mounting plate 52. The flange portion of the casing 50 is fixed to the mounting plate 52 by, for example, screwing. The detection outputs of the force detection elements 40a and 40b are led out through conductors 53a and 53b. According to the present invention, the first and second force detecting elements 40a,
The force detection directions F ₁ and F ₂ of 40b are perpendicular to each other. It is also assumed that a flat magnet is mounted on the back surface of the mounting plate 52. Therefore, the whole vibration detector 40 can be easily attached to and detached from the vibrating body by the magnet.

Further, according to the present invention, A /
From the outputs A and B of the D converters 43a and 43b and the output of the phase difference detector 44, the amplitude and the vibration angle in the major axis and minor axis directions are calculated by the methods described later. As described above, the liquid crystal display unit 47,
48 and 49 are displayed as digital values.

FIG. 8 shows the elliptical vibration V of the trough 2 in an enlarged manner. From the outputs of the detecting elements 40a and 40b in the above-mentioned vibration detector 40, the elliptical vibration V The amplitude A in the major axis direction X-X and the amplitude B in the direction perpendicular to this are calculated. In FIG. 8, the elliptical vibration V in the x-axis direction of the elliptical vibration V corresponds to the horizontal x-axis direction and the vertical y-direction in FIG. And the amplitude in the y- axis direction is b
Then these are x = a sinωt and y = bs
expressed as in (ωt + φ), which are detection element 40
a, 40b . An elliptical vibration force is obtained by a combined force of the vibration force in the x-axis direction and the vibration force in the y-axis direction, whereby the trough 2 performs the elliptical vibration V. According to the present embodiment, the detection element 40a and the 40b
Is detected by the phase difference detector 44,
It is supplied to the computer 45. Here, the relationship between the phase difference φ between the vibration force b sin (ωt + φ) in the y-axis direction and the vibration force x = a sin ωt in the x-axis direction and the mode of the elliptical vibration will be described. A linear oscillation is performed as shown. This vibration angle corresponds to θ in FIG. 8, and is a vibration easily obtained by, for example, a conventionally known electromagnet driving unit.
The mode changes depending on the phase difference of the force in the x-axis direction and the y-axis direction.
When φ <90 °, elliptical vibration occurs as shown by B,
The trajectory is different in the plus displacement direction and the minus displacement direction of the vibration. In the plus displacement direction, the vibration oscillates in an upper portion of the trajectory as indicated by an arrow, and in the minus displacement direction, oscillates in a lower trajectory. That is, the vibration is performed while drawing a locus around the clockwise direction. As shown by C in FIG. 5, when φ = 90 °, the direction of the major axis of the ellipse is parallel to the x-axis direction, and therefore, the direction of the minor axis perpendicular to this is parallel to the y-axis. Further, when φ is 90 ° <φ <180 °, the direction of the major axis of the ellipse is inverted with respect to the x-axis, but the trajectory of the vibration is clockwise as indicated by the arrow. Also, as shown in FIG.
If the angle is 0 °, linear vibration is performed, but the inclination angle of the linear vibration is the inclination angle in the direction opposite to the direction of the linear vibration in FIG. Furthermore φ
When 180 ° <φ <270 °, the elliptical vibration is performed, but the direction is opposite to the direction shown in FIG. 5B, and the trajectory of the vibration is counterclockwise. Further, as shown by C in FIG.
At 70 °, elliptical vibration occurs, but the major axis is parallel to the x-axis direction, and the trajectory of the vibration is counterclockwise as indicated by the arrow. Further, when φ is 270 ° <φ <360 °, FIG.
As shown by D, the direction of the long axis is the same as B in FIG. 5, but the trajectory of the vibration is counterclockwise.

[0014] The thus vibrate mode by a phase difference of the vibration force in the x axis direction and y axis direction is although to change, such φ is detected by the phase difference detector 44 in FIG. 1, the size 5 and FIG.
The direction of vibration rotation can be easily understood .

The outputs from the A / D converters 43a and 43b are calculated by the computer 45. If the calculated values are a and b, the following equations (1) and (2) are used.
Fuhaba A of the major axis in FIG. 8 by the arithmetic expressions such as 2, the minor axis Fuhaba B, vibration angle θ is calculated. These A, B, θ
The transfer speed changes depending on the size of the
In addition to the direction, it is also necessary to obtain these values.
Above, it is effective.

[0016]

(Equation 1)

From the above equation 1, the amplitude A in the major axis direction, that is,
The maximum value of the vibration displacement in the X-axis direction from the origin 0 and the amplitude B in the short-axis direction, that is, the maximum value of the vibration displacement in the Y-axis direction from the origin 0
The value and the vibration angle θ are represented by the following Expression 2.

[0018]

(Equation 2)

The above A, B and θ are calculated by digital values in the CPU 45.
In this embodiment, b is measured with higher accuracy than in the prior art as follows. That is, each output of the vibration detector 40 has a sinusoidal waveform as a whole, but includes noise, and large noise often exists for some reason. When calculating the amplitude, the amplitude is measured from the maximum value and the minimum value by double integration, so that when a large noise is generated, the amplitude is measured larger than the actual amplitude. Will be. If it is an ideal sine waveform without such noise, there is no problem and accurate measurement can be performed.In general, noise of various sizes is often included. According to this, this effect can be eliminated.

That is, the amplitude component in the F ₁ direction to be measured (F
Consider only _one direction, the same applies to the F ₂ direction. ) Is At, the displacement x at each time is given by Equation 3 below.

[0021]

(Equation 3)

In this embodiment, the acceleration mean square R.F. M.
S. (Root Mean Square), that is, calculate the effective value. That is, the acceleration at each moment is integrated over time, divided by the time during this time, and the average value is obtained to obtain the following Expression 4.

[0023]

(Equation 4)

Accordingly, the amplitude component is obtained from the above equation (4) as shown in the following equation (5), and this is used as a in the above equation.

[0025]

(Equation 5)

That is, the twice-differentiated value of x is measured at each instant, and the amplitude component At is calculated by taking the time-averaged value. Therefore, even if a large noise is generated in a short time by taking an average value at a certain time, this effect can be almost ignored.

The F ₂ direction is calculated in the same manner, and the amplitude component in this direction is obtained as shown in the following Expression 6, which is the above b.

[0028]

(Equation 6)

As described above, according to the present embodiment, the amplitude of the major axis and the minor axis of the elliptical vibration can be accurately obtained even if the vibration detector 40 is attached to the vibrating body arbitrarily. The vibration angle θ of the long axis is with respect to the detection direction of the force detection element 40a.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited thereto, and various modifications can be made based on the technical concept of the present invention.

For example, in the above embodiment, the output of the vibration detector is displayed as a digital value on the display unit, but may be displayed in an analog manner instead.

The outputs of the force detecting elements 40a and 40b are set to 2
Instead of calculating the amplitude by performing integral times, a vibration detecting element or a detector capable of directly measuring the amplitude may be used. When measuring the vibration angle with respect to the horizon,
The sensor should be installed so that the detection direction of the output element is horizontal.
No.

[0033]

As described above, the vibration feeder according to the present invention is used.
According to the elliptical vibration detection method, the mounting member is mounted so that the detection direction of the detection element is parallel to a plane parallel to the vibration direction of the vibration feeder , so when measuring only the amplitude of the long axis and the short axis No adjustment is necessary for any vibrator to match the detection direction to the vibration direction,
The amplitude can be accurately measured without providing any special member. Also, vibration in the first predetermined direction
Angles can also be measured.

[Brief description of the drawings]

FIG. 1 is a circuit diagram for implementing the method of the present invention.

FIG. 2 is a side view of a resonance type vibration feeder in which a vibration detector embodying the present invention is mounted and a vibration motor is used as a vibration unit.

FIG. 3 is a perspective view of the vibration detector.

FIG. 4 is a plan view showing an arrangement of force detection elements in the vibration detector.

FIG. 5 is a diagram showing a phase difference between vibration forces in each axis direction in rectangular coordinates and a mode of elliptical vibration generated by the phase difference, wherein A denotes elliptical vibration when the phase difference φ is 0, that is, a straight line; Vibration graph. B is a graph of the elliptical vibration when φ is 0 to 90 degrees. C is a graph of the elliptical vibration when the phase difference φ is 90 degrees. D is a graph of the elliptical vibration from 90 degrees to 180 degrees.

6A is a graph of an elliptical vibration at φ = 180 degrees, FIG. 6B is a graph of an elliptical vibration mode at a phase difference φ in a range of 180 degrees to 270 degrees, and C is φ = 270 degrees.
11 is a graph of the mode of the elliptical vibration in degrees, and D is a graph of the mode of the elliptical vibration when the phase difference φ is in the range of 270 degrees to 360 degrees.

FIG. 7 is a side view showing vibration of a resonance type vibration feeder using a vibration motor as a vibration source.

FIG. 8 is a graph showing an enlarged elliptical vibration in the vibration feeder.

FIG. 9 is a front view of an amplitude nameplate used for measuring an amplitude by a conventional method.

FIG. 10 is a front view showing the same operation.

FIG. 11 is a front view of an angle nameplate used for measuring a vibration angle by a conventional method.

FIG. 12 is a side view of a resonance-type vibration feeder using a vibration motor to which the angle nameplate is attached as a vibration source.

[Explanation of symbols]

Reference Signs List 40 Vibration detector 40a Detection element 40b Detection element 44 Phase difference detector 45 Computer A Long axis B Short axis

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Claims (2)

(57) [Claims] 1. A first vibration detecting element for detecting vibration in a first predetermined direction is mounted on a surface parallel to a vibration direction of a vibration feeder , and a second predetermined direction perpendicular to the first predetermined direction. A second vibration detecting element for detecting the vibration of
Mounted on a plane parallel to the vibration direction of Ida, the detection output and the phase difference φ of these detection outputs of the first vibration detection element and the second vibration detecting element, the vibration Fi by calculation
First Fuhaba the long axis direction of the elliptical vibration of the over da, in the minor axis direction second
A vibration feeder for obtaining a vibration amplitude and a vibration angle [theta] with respect to the first predetermined direction in the major axis direction.
Elliptical vibration detection method of. 2. The method according to claim 1, wherein the first amplitude and the second amplitude are respectively
Let A, B be the detection outputs of the first and second vibration detection elements, a and b, respectively, from the following equations, A, B and θ
The elliptical vibration detection method according to claim 1, wherein is obtained by calculation. A ² = (a cos θ) ² + (b sin θ)
² + ab sin2θ · cosφ, B ² = (a sin
θ) ² + (b cos θ) ² −ab sin2θ · co
sφ, tan2θ = 2ab cosφ / (a ² −b
² ).