WO2001020256A1

WO2001020256A1 - Device for measuring width and position of object

Info

Publication number: WO2001020256A1
Application number: PCT/JP1999/004944
Authority: WO
Inventors: Takashi Yoshida; Yuichi Komazawa
Original assignee: Technowave, Ltd.
Priority date: 1999-09-10
Filing date: 1999-09-10
Publication date: 2001-03-22

Abstract

A measuring device characterized in that the device has a construction in which a measuring section (5) movable along a rod (3) of a linear sensor (1) and a measuring section (6) movable along a rod (4) of a linear sensor (2) are coupled and the linear sensors (1, 2) are so crossed that the crossing is the place where the measuring sections (5, 6) are coupled, in that the linear sensor (1) is supported in the vicinity A of one end of a measurement region swingably around one end of the rod (3) whereas the linear sensor (2) is supported in the vicinity B of the other end of the measurement region swingably around the other end of that rod (4), in that when an object is placed on a reference face, the angle between the rod (3) and the rod (4) is changed and accordingly the measuring sections (5, 6) move along the rod (3) and the rod (4), respectively, and in that the width and/or position of the object are determined by using information on the positions of the measuring sections (5, 6).

Description

Specification

Device for detecting the width and position of the measured object

The present invention relates to a detection device for detecting the width and Z or position of an object to be measured, and more particularly, to a detection device for detecting the width and Z or position of an object to be measured using a linear sensor. Background art

Conventionally, there are various methods for detecting the width and position of an object to be measured. Hereinafter, a typical conventional method (apparatus) and its problems will be described. Laser type

This method measures the width and position of an object by irradiating the object with a laser beam and scanning. Although high-precision measurement is possible due to the characteristics of lasers, there are problems with slow processing time, severe restrictions on environmental use conditions, and complexity. Ultrasonic method

This method measures the distance to an object by oscillating ultrasonic waves toward the object and capturing the reflected waves. Temperature compensation is also required due to the characteristics of ultrasonic waves, and accuracy cannot be expected and is unstable. Another problem is that simultaneous measurement from multiple angles is difficult due to the problem of mutual interference. Infrared method This is the most widely used method in the past, and it is a method that detects that infrared rays are separated by an object, and measures the width and position by using multiple infrared rays. Since multiple sensors are required as in the case of the contact type, high accuracy cannot be expected, and there is a problem that the cost tends to be high. Mechanical switch type

This method measures the width and position of a target object by using mechanical switches and combining them. Although the reaction speed is high, there is a problem that a large number of switches are required to increase the accuracy, and the structure is complicated and difficult to handle. Image recognition method

This method measures the width and position using image recognition based on the image data of the object. High-precision measurements require high-performance cameras, CPUs, and large amounts of memory, and are complex, expensive, and slow. As described above, conventional detection devices for measuring the width and position of an object to be measured, such as luggage, are complicated, insufficient in speed, have large restrictions on use conditions, and are expensive. And all had problems.

Therefore, the present invention provides a simple, compact, high-speed, inexpensive and highly durable device for detecting the width and position of an object to be measured such as luggage. Disclosure of the invention

The invention according to claim 1 has a detection unit movably mounted, and a pair of linear sensors for detecting a relative positional relationship from an end to the detection unit. Each linear sensor is swingably supported on a different one end as a fulcrum, and when the object to be measured is placed on the pair of linear sensors, each linear sensor changes the crossing angle. A detection device for detecting a width and a position or a position of the object to be measured from a moving position of the detection unit. The invention according to claim 2 is characterized in that the object to be measured is supplied into a measurement area having a predetermined width, each fulcrum of the linear sensor is set at a boundary of the measurement area, and the detected 2. The detection device according to claim 1, wherein a width and a Z of the object to be measured or a position in the measurement area are obtained from a movement position of the part.

The invention according to claim 3 includes a linear sensor 1 and a linear sensor 2, and a detecting unit 5 that moves along a rod 3 of the rear air sensor 1 and a detecting unit 6 that moves along a rod 4 of the linear sensor 2. The linear sensor 1 and the linear sensor 2 have a structure in which the linear sensor 1 and the linear sensor 2 can intersect with each other with the coupled detecting section as an intersection. The linear sensor 2 is swingably supported with one end as a fulcrum, and near the other end B of the measurement area, a linear sensor 2 is arranged along a plane parallel to the rotation surface of the linear sensor 1 with one end of the rod 4 as a fulcrum. When the object to be measured is placed on the reference surface, the angle formed by the rods 3 and 4 changes, and the angle formed by the rods 3 and 4 changes. Detection unit 5 and detection unit 6 And a mechanism for moving along the rods 3 and 4 and detecting the width and Z or the position of the measured object using the position information of the detection units 5 and 6. It is.

The position detecting device of the present invention uses a linear sensor. Here, the linear sensor is a sensor that detects a speed and a moving distance that change linearly. For example, a known linear encoder is used. For example, as shown in Fig. 1 It has a detection unit 5 and detects a relative positional relationship between the detection unit 5 and the rod unit 3. In the linear encoder 1 of FIG. 1, the detection unit 5 can move along the rod, and the detection unit 5 can measure the length XI between the end of the rod 3 and the detection unit. It is needless to say that the linear sensor used in the present invention is not limited to the one shown in FIG.

In a mechanism in which a pair of linear sensors form an angle around the detection unit when the device under test is placed on the reference surface, the length (distance) from the end of each linear sensor to the detection unit is detected. The width of the package and the distance from the edge of the reference plane can be detected.

At this time, the reference surface is the surface on which the device to be measured is mounted, but the table on which the device to be measured is actually mounted is often divided to insert the linear sensor. The reference plane in the present invention is a virtual plane.

The invention described in claim 4 includes an arm 7 having a parallel or constant angle with the rod 3 of the linear sensor 1 and an arm 8 having a parallel or constant angle with the rod 4 of the linear sensor 2. The arm 7 and the arm 8 are pushed down by being placed on the reference surface, thereby causing the rods 3 and 4 to change their angles. 6 has a mechanism for moving along the rods 3 and 4, respectively, and detects the width and the Z or the position of the measured object using the position information of the detection unit 5 and the detection unit 6. The detection device according to any one of claims 1 to 3, wherein:

By separating the rod from the arm that comes into contact with the object to be measured, the detection unit does not come into contact with the object to be measured, protecting the detection unit from impact and making more accurate measurements edible.

In addition, when the two rods are parallel to each other, it becomes a singular point, and the detection unit does not move. However, by setting an offset angle between the arm and the rod, it can be set to avoid this singularity.

The invention described in claim 5 is a physical distribution system using a belt conveyor, comprising a control unit, and the detection device described in any one of claims 1 to 4, This is a logistics system that detects the width and Z or position information of the cargo being transported.

In the invention according to claim 6, the detection device according to any one of claims 1 to 4 is installed between a belt conveyor and the belt conveyor, and the detection surface of the conveyance surface of the belt conveyor is provided. 6. The distribution system according to claim 5, wherein the extension surface is a reference surface.

A computer or the like is used as the control unit. The detection device described in claims 1 to 4 is used in a logistics system to detect the width and / or position of the package on the conveyor at any time, and the control unit processes the information. A high performance logistics system can be realized.

The invention described in claim 7 is characterized in that the shape and the Z or posture of the load are measured by continuously detecting the width and the Z or the position of the load as the load moves. The logistics system according to claim 5 or claim 6.

By continuously detecting the width and position of the luggage moving on the conveyor, data on the change over time in the width and position of the luggage can be obtained, so that the shape and posture of the luggage can be known. An advanced logistics system can be realized by using the shape and posture information of the package. BEST MODE FOR CARRYING OUT THE INVENTION

(Example 1) FIG. 2 shows a state before the object to be measured is placed. Above both ends of the reference plane, one end of the rod 3 is linearly supported as shown in Fig. 1 and one end of the rod 3 is swingably supported around one end A of the measurement area as a fulcrum. A linear encoder 2 is pivotally supported at one end of a rod 4 around the other end B of the measurement area as a fulcrum, and the detection units 5 and 6 of the pair of linear encoders 1 and 2 are rotatable. Is joined to.

Here, as shown in Fig. 3, when the DUT is placed on the linear encoder, the DUT sinks down to the reference plane while pushing down the rods 3 and 4 of the linear encoders 1 and 2 due to its weight. Will be. Therefore, the difference in height between the reference plane and the fulcrum A (the same is true for the fulcrum B) causes the rods 3 and 4 of the pair of linear encoders to have an angle. Note that the fulcrums A and B are provided with a mechanism such as a panel, and the rod portion of each of the retro encoders is prevented from moving downward beyond the angle depressed by the load.

At this time, the connected detectors 5 and 6 move on the rods 3 and 4 along the rods 3 and 4, respectively, as the angles of the rods 3 and 4 change.

This is shown in Figure 4 when viewed from the side.

The height s to the fulcrums A and B, the distance y from the intersection of the detection units 5 and 6 to the fulcrums A and B, and the width L of the measurement area are known. When the object to be measured is placed on the reference plane, the angle between the rod 1 and the rod 2 changes, and the respective detection units 5 and 6 move. At this time, distances XI from fulcrum A to detector 5 and distances X2 from fulcrum B to detector 6 are measured by detectors 5 and 6, respectively.

Then, using these numerical values, the width and position of the DUT on the reference plane can be calculated, for example, by the following mathematical formula. At this time, L and s are known. XV = n ² + y ~

This eliminates y ((Equation 1)

XI ² -n ² = X2 ^2- (L ~ n)

n ^ — (L ² + XI ² -X2 ² ) cos (9, =

X \

θ, = cos ——

y = X _x -sin θ _λ

Y

s (L-n)

d3

y

d2 = L-d \ -d3 dl and d3 are the distances from the end of the measurement area to each end face of the DUT, and d2 is the width of the DUT.

Although this embodiment shows a case where the angle between the plane on which the linear encoder swings and the reference plane is 90 degrees, this need not be 90 degrees.

Further, the detection unit 5 and the detection unit 6 may have an integrated structure. (Example 2)

Next, an example in which the present invention is used to detect the width and position of a load flowing on a belt conveyor in a physical distribution relationship will be described.

The luggage 12 flows from the conveyor 10 to the conveyor 11, and the detection device of the present invention is installed at a portion (joint) between the belt conveyors 10 and 11. Have been.

6 (A) to 6 (C) show a state before the package 12 which is the object to be measured reaches the detection device.

As shown in FIG. 5, the rod 3 of the linear encoder 1 has an arm 7 with a fixed angle, and is swingable about A. The rotation of the arm 7 is tensioned by the panel, and when the load is not on the arm, the arm 7 is raised above the reference plane as shown in FIG.

The relationship between the rod 4 and the arm 8 in the linear encoder 2 is the same with B as a fulcrum.

The luggage 12 flows on the belt conveyor 10 and gets on the arms 7 and 8 when reaching the belt conveyor 11.

This state is shown in FIGS. 7A to 7C and FIG.

Arms 7 and 8 are provided with anti-trapping covers 13 so that luggage 12 is not caught when riding on both arms 7 and 8.

The luggage 12 pushes down on both arms 7 and 8 by resting on both arms 7 and 8, and both arms 7 and 8 rotate downward around fulcrums A and B, respectively. Then, along with this, both rods 3 and 4 also rotate around each fulcrum, and the connected detecting parts 5 and 6 also move, and their relative positions XI, on the rods 3 and 4, respectively. Transform X2.

In addition, both arms 7 and 8 are configured not to move downward beyond the amount pushed down by the load 12 due to the tension of the spring described above.

FIG. 9 shows the state of the detection device in this state, such as the angle of the rod.

Here, using the known values L, s, and _r and the axes XI and X2 measured by the detectors 5 and 6 of the linear encoders 1 and 2, dl to d3 are calculated as follows. . XI ² = n ² + z ²

This eliminates z. (Equation 2)

Χ ~ η- = XI ^1- (Ln)

η = ~ (ΐ} + Χ \ ² -Χ2 ² )

L-n

COS, =

X2

r-1 s COS0 _]

sin ^

rs cose ₂

d3 =

sin d2 = L-d \ -d3 The calculation is performed by a computer included in this distribution system. Thus, the width and position of the load can be detected, and the shape and attitude of the load can be known by continuously measuring these values as the load moves.

(Example 3)

Further, in the same physical distribution system as in the second embodiment, an embodiment in which the detection device of the present invention in which the opening and arm of the linear encoder have offset angles is used. Is shown. In this case, FIG. 10 shows a state in which a package is placed on the detection device of the present invention.

By providing an offset angle between the rod and the arm, it is possible to avoid a singular point when the rods 3 and 4 are parallel. In this example, the reference plane and the rod fulcrums A and B coincide with each other, but may not necessarily coincide with each other. At this time, the known values L, r, Θ. Using the values XI and Χ2 measured by the linear encoders 1 and 2, dl to d3 are calculated as follows.

(Equation 3) in the same way as (Equation 2)

L ² + Χ -X2 ²

θ,-cos—

2L

=

λ = θ, -θ ₀

φ ₂ = θ ₂ -θ ₀ d \

sin

r

d3 =

sin

d2 = L-d \ -d3 Industrial availability

As described above, the position detection device of the present invention can measure the object without being affected by the height and color of the object to be measured, and has a high-speed, high-accuracy, and linear response characteristic. In addition, since the mechanism is simple, a device that is small and has a low failure rate can be realized. In addition, a contact-type mechanical mechanism Therefore, stable measurement is possible with little influence from the environment. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a linear encoder.

FIG. 2 is a conceptual diagram of the detection device of the present invention (in a state in which an object to be measured is not mounted). FIG. 3 is a conceptual diagram of the detection device according to the present invention (in a state where an object to be measured is placed). FIG. 4 is a diagram showing a state of each unit in a state where the device to be measured is placed on the detection device of the present invention.

FIG. 5 is a diagram showing an example of mounting an arm.

FIG. 6 is a view showing an embodiment of the physical distribution system of the present invention (in a state where an object to be measured is not mounted).

FIG. 7 is a diagram (in a state where an object to be measured is placed) showing an embodiment of the physical distribution system of the present invention.

FIG. 8 and FIG. 9 are diagrams showing the state of each part in a state where the device to be measured is placed on the detection device in the embodiment of the distribution system of the present invention.

FIG. 10 is a diagram showing a state of each part when an offset angle is given to the rod and the arm.

Claims

The scope of the claims

1. A pair of linear sensors having a detection unit movably mounted, and detecting a relative positional relationship from an end to the detection unit,

Each of the return sensors is swingably supported with a different end as a fulcrum. When an object to be measured is placed on the pair of linear sensors, each linear sensor changes the crossing angle, and the detecting section A detection device for detecting a width and a Z or a position of the object from a moving position.

2. The device under test is supplied in a measurement area having a predetermined width,

Each fulcrum of the linear sensor is set at a boundary of the measurement region, and a width of the measured object and / or a position in the measurement region is obtained from a detected movement position of the detection unit. The detection device according to range 1.

3. Equipped with linear sensor 1 and linear sensor 2,

A detection unit 5 that moves along the rod 3 of the linear sensor 1 and a detection unit 6 that moves along the mouth 4 of the linear sensor 2 are connected, and the combined detection unit is used as an intersection point and the linear sensor 1 And the linear sensor 2 has a structure capable of intersecting with the linear sensor 1. Near the one end A of the measurement area, the linear sensor 1 is swingably supported with one end of the rod 3 as a fulcrum,

In the vicinity B of the other end of the measurement area, a linear sensor 2 is supported by a rocking itself along a plane parallel to the rotation surface of the linear sensor 1 with one end of the rod 4 as a fulcrum,

When the DUT is placed on the reference plane, the rod 3 and rod 4 A change occurs in the formed angle, and the detection unit 5 and the detection unit 6 have a mechanism for moving along the rod 3 and the rod 4 with the change in the angle of the rod 3 and the rod 4, respectively.

A detection device characterized by detecting the width and 7 or the position of the measured object using the position information of the detection unit 5 and the detection unit 6.

4. An arm 7 having a parallel or constant angle with the rod 3 of the linear sensor 1 and an arm 8 having a parallel or constant angle with the rod 4 of the linear sensor 2;

When the load is placed on the reference surface, the arm 7 and the arm 8 are pushed down, thereby causing the rods 3 and 4 to change their angles. 5 and a detector 6 have a mechanism for moving along the rod 3 and the mouth 4, respectively.

The width and / or the position of the device under test is detected using the position information of the detection unit 5 and the detection unit 6, wherein the width and / or the position of the object to be measured are detected. Detection device.

5. A logistics system using a belt conveyor, which has a control unit and the detection device according to any one of claims 1 to 4, and has a width and a Z or A logistics system characterized by detecting location information.

6. The detecting device according to any one of claims 1 to 4 is installed between the belt conveyors, and the extension surface of the conveyor surface of the belt conveyor becomes a reference surface. Claim 5 characterized in that

.Logistics described

7. Claim 5 or claim 6 characterized by measuring the shape and Z or posture of the load by continuously detecting the width and Z or position of the load as the load moves. The logistics system described in 1.