JPH06271040A - Transfer device - Google Patents

Abstract

PURPOSE:To provide a transfer device in which precision of work transfer positions can be improved by detecting an error in a transmission ratio by tolerance of a pulley used as a rotation transmission means, and correcting rotation quantity to be obtained by use of the error. CONSTITUTION:A transfer device is provided with a first rotation detector 22 to detect rotation of a first pulley 12, a second rotation detector 24 to detect rotation of a second pulley 14, and a computation means (control device 26) to compute a correction value based on difference between rotation quantity of the second pulley 14 to be obtained to a specified rotation quantity of the first pulley 12 detected by the first rotation detector 22, and detected rotation quantity of the second pulley 14 obtained by the second rotation detector 24. In addition, a control means (control device 26) is provided to correct the rotation quantity to be set for the first pulley 12 based on a rotation transmission ratio to the rotation quantity to be obtained by the second pulley 14, and drive a drive source 10 to obtain the rotation quantity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conveyance device using a pulley for which a rotation transmission ratio is set as a rotation transmission mechanism.

[0002]

2. Description of the Related Art A conveying device for conveying an object to be conveyed by using a pulley as a rotation transmission mechanism is provided with a pair of conveying rollers 2 and 4, for example, as shown in FIG. The conveyor belt 6 is wound around. The transferred object 8 is placed on the transfer belt 6 and is rotated, for example, to be transferred in the direction of arrow A. Therefore, each transport roller 2,
4 is the transport distance of the transported object 8, that is, the transport start position P _O
Is set to cover the distance ΔP from the transport position P ₁ to.

A motor 10 is installed as a drive source in the carrying device, and the pulley 10 is installed as a speed reduction means while transmitting the rotational force to the carrying roller 4 side. This pulley device includes a pair of pulleys 12 and 14, and a belt 1 is provided between the pulleys 12 and 14.
6 is running around. That is, the pulley 12 has the drive shaft 11
When a rotational force is applied from the motor 10 through the pulley 14, the rotation is transmitted to the pulley 14 via the belt 16 and the pulley 14
Therefore, the rotation amount according to the pulley ratio between the pulleys 12 and 14 can be obtained. In this example, since the diameter of the pulley 14 is larger than that of the pulley 12, the pulleys 12 and 14 are in a deceleration relationship. Unlike a belt gear mechanism using a gear mechanism or a timing belt, such a pulley device does not have a troublesome setting of the tooth number ratio and can set a large rotation ratio. Even if the diameter of the pulley 12 is extremely reduced, the rotation transmission is not impaired, and the pulley 12 has an advantage that it can be used as a rotation transmission means that is reduced in size and weight. Therefore, the conveyance device can also be reduced in size and weight.

[0004]

SUMMARY OF THE INVENTION Such a pulley 1
In the transport device having the rotation transmission mechanism 2 and 14, the pulley 1
2 and 14 can be set to an arbitrary rotation ratio, while pulley 1
Due to the tolerance of the diameters of 2 and 14, and other factors, an error occurs in the actually transmitted rotation amount, and precise rotation transmission cannot be obtained, so that there is a possibility that the conveyance position may shift.

Here, each diameter D ₁ of the pulleys 12 and 14 is
The D _2, and _{D 1 = 5.00 ± 0.05mm D 2} = 50.00 ± 0.05mm. In this case, the minimum value L of the outer circumference L ₁ of the pulley 12
_1min , standard value L _1typ and maximum value L _1max are L _1min = 4.95 × π = 15.55mm L _1typ = 5.00 × π = 15.71mm L _1max = 5.05 × π = 15.87mm , The minimum value L _2min of the outer circumference L ₂ of the pulley 14,
Standard values L _2Typ and maximum value L _2max becomes _{L 2min = 49.95 × π = 156.92mm} L 2typ = 50.00 × π = 157.08mm L 2max = 50.05 × π = 157.24mm.

From these relationships, the minimum value n _min (= L _1max : L) of the rotation transmission ratio (pulley ratio) n (= L ₁ : L ₂ ).
_{2 min} ), standard value n _typ (= L _1typ : L _2typ ), and maximum value n _max (= L _1min : L _2max ), n _min = 1: 9.89 (= 15.87: 156.9)
2) n _typ = 1: 10.00 (= 15.71: 157.0)
8) n _max = 1: 10.11 (= 15.55: 157.2)
4)

Therefore, when the pulley 12 is rotated N ₁ = 100 times, from the rotation transmission ratios n _min , n _typ and n _max , the minimum value N _2min and the standard value N ₂ of the rotation amount N ₂ obtained on the pulley 14 side are obtained. _2Typ and maximum value N _2max becomes _{N 2min = 9.89 N 2typ = 10.00} N 2max = 10.11.

Thus, each pulley 12, 14 has a diameter D
_Since there is a tolerance between ₁ and D ₂ , a rotation deviation (error) occurs in the rotation amount N ₂ of the pulley 14 with respect to the pulley 12. The transfer of the conveyor belt 6 is closely related to the rotation of each pulley 12, 14 and the belt 16, that is, the rotation amount,
The rotational deviation caused on the pulleys 12 and 14 side is caused by the transported object 8.
A positional deviation will occur at the transport position P ₁ of the above. Such a deviation occurs as long as the diameters of the pulleys 12 and 14 have tolerances, regardless of the diameters set for the pulleys 12 and 14.

When it is necessary to detect the minute rotation amount of the pulley 14, it is necessary to use the rotation detector 15 capable of accurately detecting the rotation amount, but the accuracy is limited. Therefore, the rotation detector 15 is attached from the pulley 14 side to the pulley 12 side, that is, the deceleration first stage side, so that the pulley 14 with respect to the rotation amount of the rotation detector 15 is attached.
I have avoided getting a fine rotation amount. That is, the requirement for detection accuracy is relaxed.

When the rotation detector 15 is provided on the pulley 12 side to detect the rotation amount on the pulley 12 side,
Assuming the rotation amount on the pulley 14 side from the detected value is still a problem because the rotation amount obtained on the pulley 14 side is different from the expected value due to the tolerance existing between the pulleys 12 and 14. Therefore, when the conveyed body 8 is transferred to a predetermined position (conveyance position P ₁ ) in response to the rotation of the pulley 14, the decrease in the rotation amount accuracy greatly affects the conveyance position accuracy.

Therefore, the present invention detects the error of the transmission ratio due to the tolerance of the pulley used as the rotation transmitting means, and corrects the rotation amount to be obtained by this error to improve the accuracy of the transfer position of the object to be transferred. An object of the present invention is to provide an enhanced transport device.

[0012]

The transport device of the present invention is a transport device for transporting an object to be transported (8) by a transport belt (6) suspended between a pair of transport rollers (2, 4). The first pulley (pulley 12) that rotates by receiving the rotational force from the drive source (motor 10) and the belt (16) suspended between the first pulley to receive the rotation. , A second pulley (pulley 14) for rotating the conveying roller, a first rotation detecting means (rotation detector 22) for detecting the rotation of the first pulley, and a rotation of the second pulley Second rotation detecting means (rotation detector 24)
And a rotation amount of the second pulley that should be obtained with respect to a predetermined rotation amount of the first pulley detected by the first rotation detecting means, and the first rotation amount obtained by the second rotation detecting means. Computation means (control device 26) for calculating a correction value from the difference between the detected rotation amount of the two pulleys, and storage means (ROM 266, RAM) for storing the correction value obtained by this computation means.
268) and the rotation amount to be set in the first pulley by the rotation transmission ratio between the first and second pulleys with respect to the rotation amount to be obtained in the second pulley, read from the storage means. Control means (control device 26) for controlling the drive source so as to obtain the amount of rotation by correcting with the correction value
It is characterized by having and.

[0013]

The rotation transmission error based on the tolerance generated between the first and second pulleys is detected, and the detected rotation transmission error is stored in the storage means. Since the rotation amount set for the first pulley is determined from the rotation transmission ratio with respect to the rotation amount to be obtained by the second pulley, this rotation amount is corrected by the correction value. Therefore, as a result of the correction of the rotation amount of the first pulley, a highly accurate rotation amount can be obtained for the second pulley. Therefore, the tolerance existing in the first and second pulleys is the result of the correction,
As a result, the precision of the transport position of the transported object transported by the transport roller and the transport belt which is rotated by the second pulley is improved.

[0014]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment of the carrying device of the present invention. For example, a pair of transport rollers 2 and 4 is installed in this transport device, and a transport belt 6 that carries and transports a transported object 8 is suspended between the transport rollers 2 and 4. Each of the transport rollers 2 and 4 is set to a distance that covers the transport distance of the transported object 8, that is, the distance ΔP from the transport start position P _O to the transport position P ₁ . In this embodiment, the conveying rollers 2 and 4 are set to have the same diameter, the conveying roller 4 side is set to the driving side, and the conveying roller 2 is set to the driven side which receives the rotation of the conveying roller 4 via the conveying belt 6. ing.

A pulley device 9 is installed on each of the carrying rollers 2 and 4 and the carrying belt 6 as a means for applying a driving force obtained from a motor 10 as a driving source to the carrying roller 4 side. The pulley device 9 includes the first and second pulleys 1
A belt 16 is provided around the pulleys 12 and 14 as a means for transmitting rotation between the pulleys 12 and 14. In this embodiment, the pulley 12 is the drive side that receives the rotational force from the drive shaft 11 of the motor 10, and the pulley 14 is the belt 1.
6 is set on the driven side to rotate. Further, in this embodiment, the pulley 14 has a larger diameter than the pulley 12 and constitutes a deceleration transmission mechanism for decelerating the rotation on the pulley 12 side.

The drive shaft 11 of the pulley 12 has a rotation detector 22 as a first rotation detecting means for electrically detecting the rotation of the pulley 12, and the rotation shaft 13 of the pulley 14 has a second rotation detecting means as a second rotation detecting means. A rotation detector 24 that electrically detects the rotation of the pulley 14 is provided. Each rotation detector 2
2, 24 can be configured by encoders or the like that convert rotation into pulses.

Further, the conveyor 12 includes pulleys 12, 1
A control unit 26 is installed, which is a control unit that controls the rotation of the motor 10 based on the rotation amount correction on the pulley 12 side, as well as a calculation unit that calculates a rotation transmission error between the four.
The control device 26 is composed of a microcomputer having a storage means inside.

This control device 26 includes each rotation detector 2
The detection outputs of 2 and 24 are input / output units (I / O) 262.
Be captured through. Further, a reset signal R indicating power-on is input to this I / O 262 through a detection means (not shown). Further, a control output is taken out from this I / O 262, and the control output is added to the drive device 28 which drives the motor 10. The drive device 28 receives the control output and supplies a drive current to the motor 10 to give the motor 10 the rotation amount represented by the control output. Further, in the correction value acquisition control, if the control range is exceeded, I / O 262
An alarm output is emitted from the and is added to the alarm device 30 installed as a warning means. The alarm device 30 can be composed of a light emitting means such as a light emitting diode or the like, and a sounding device such as a buzzer or the like that appeals to the hearing.

A central processing unit (CPU) 264 for performing calculation and control is installed in the control device 26, and the CPU 264 has a ROM 266 and an R as storage means.
AM268 is connected through a bus. As is well known, the ROM 266 is a read-only memory, which stores a control program and correction value table values and the like. Therefore, the control and arithmetic processing of the CPU 264 is executed based on the control program read from the ROM 266. The RAM 268 is a memory that can be read from and written to at any time, and stores a correction value fetched by the correction control in order to compensate a rotation amount error, which is the main data of the present invention, in addition to the data in the process of being calculated. Since the acquisition of the correction value is started after the power is turned on, it is related to the input of the reset signal R to the I / O 262 and the operation of the reset switch (not shown).

The correction value stored in the RAM 268 is based on the tolerance in the diameter of the pulleys 12 and 14,
A stepwise value is adopted according to the rotation amount. Further, this correction value is data for correcting the rotation amount to be set in the drive pulley 12 with respect to the rotation amount to be obtained in the driven pulley 14.

In the embodiment, the arrow A indicating the rotation direction of the conveyor belt 6 for conveying the object 8 and the arrow B indicating the rotation directions of the pulleys 12 and 14 corresponding to the rotation direction are examples thereof. It is possible to rotate in the opposite direction, and the deceleration direction of the pulleys 12 and 14 is also arbitrary,
Further, the number of linked pulleys 12 and 14 is not limited to one pair.

The control operation of such a transport device will be described. In order to simplify the explanation of this control operation, a specific numerical value is set as an example. The diameter of the pulleys 12 and 14 is D
_{If 1} and D ₂ , D ₁ = 5.00 ± 0.05 mm, D
₂ = 50.00 ± 0.05 mm, rotation detector 2
As for the detection outputs obtained at 2 and 24, it is assumed that a pulse of 100 points is obtained by one rotation of the pulleys 12 and 14. That is, the resolution is 100 pulses / revolution.

The control operation of the carrying device can be roughly classified into two processes. The first process is a correction value acquisition control, and the second process is a correction control for correcting the actual rotation amount using the correction value. 2 and 3 are flowcharts showing the correction value fetch control, and FIG. 4 is a flowchart of the actual correction control based on the correction values. 2 and 3, a indicates a connector of the flowchart.

First, the correction value fetching control is performed at any time when the power is turned on or when the correction value becomes defective, and the fetching control is performed by rotating the pulley 12 as much as required correction accuracy is obtained from the rotation detectors 22 and 24. The rotation detectors 22 and 24
The correction value to be applied to the rotation amount of the pulley 12 is calculated from the detected rotation amount obtained from the above and stored in the RAM 268.

The control of capturing the correction value will be described with reference to FIG. When the power is turned on, the reset signal R changes to I /
This is added to O262, and the correction value acquisition control is started. When the reset switch is provided, the reset signal R is input to the I / O 262 as needed, and at that time, the correction value fetch control is performed by the interrupt control.

In step S1, the rotation amount for fetching the correction value and the required rotation amount Na stored in advance in the ROM 266 are read from the ROM 266, set in the RAM 268, and the rotation amount as the output value of the rotation detector 22. Nb is calculated. The required rotation amount Na is set to a value that allows the rotation detectors 22 and 24 to detect an error due to the tolerance of the pulleys 12 and 14 and use it as a correction value. In the embodiment, Na = 100, Nb = 100 × 10
It is set to 0.

In step S2, the motor 10 which is the drive source of the pulley 12 is driven, and the process proceeds to step S3. In step S3, the rotation detector 22 detects the rotation of the pulley 12, and the rotation detector 22 monitors whether or not the rotation amount Nb is obtained. When the rotation amount Nb is reached in step S3, the process proceeds to step S4, the rotation of the motor 10 is stopped, and the process proceeds to step S5.

In step S5, the rotation amount on the pulley 14 side is detected, that is, the rotation detection amount N obtained by the rotation detector 24.
c is fetched, it is stored in the RAM 268, and the process proceeds to step S6.

In steps S6 to S16, the rotation detection amount Nc is compared with the correction value table value on the ROM 266,
The correction value of the rotation amount of the pulley 12 is stored in the RAM 268. Table 1 shows the correction value table values stored in the ROM 266.

[0031]

[Table 1]

Therefore, in step S6, the rotation detection amount Nc is detected.
Is in the range of 988 or more and 992 or less,
If it is within the range, the process proceeds to step S7 and the correction value d ₁ = 1.010 is stored in the RAM 268. next,
In step S8, it is determined whether or not the rotation detection amount Nc is in the range of 993 or more and 997 or less. If it is in the range, the process proceeds to step S9, and the correction value d ₂ = 1.005 is stored in the RAM 268. . Next, step rotation detection amount at S10 Nc is determined whether or not the range of 998 or more 1002 or less, the process proceeds to step S11 if within that range, the correction value d ₃ = 1.000 RAM 268 To store. Next, in step S12, the rotation detection amount Nc is 100.
It is determined whether or not it is in the range of 3 or more and 1007 or less. If it is in the range, the process proceeds to step S13, and the correction value
₄ = 0.995 is stored in the RAM 268. Next, it is determined whether the rotation detecting the amount Nc in step S14 is in the range of 1008 or more 1012 or less, the process proceeds to step S15 if within that range, the correction value d ₅ = 0.990 RAM 268 To store. With the above processing, the correction value d = d ₁
The storage of ~ d _{5 in} the RAM 268 is completed.

Then, the rotation detection amount Nc is 1013 or more 9
If it is out of the assumed control range of 87 or less, it exceeds the frame of the correction value table value, so that the correction value d is not set and the process proceeds to step S16 to generate an alarm signal. This alarm signal is output from the I / O 262 to the alarm device 30, and the alarm device 30 issues a visual or audible warning indicating an error. Since the limit of the correction value causes a great error in the transport position P ₁ , it means that the control is naturally stopped.

Next, the correction rotation control will be described with reference to this correction value. This correction rotation control uses the correction values d = d _{1 to} d ₅ stored in the RAM 268 by the correction value acquisition control, and calculates the rotation amount (that is, the output value) actually detected by the rotation detector 22. The procedure is to rotate the pulley 12 by that amount. As shown in FIG. 4, in step S21, in order to obtain the rotation transmission ratio, that is, the pulley ratio n and the rotation amount Nd of the pulley 14, the rotation detection amount Ne obtained from the rotation detector 22 is calculated, and then step S22. Move to.

In step S22, the correction value d obtained by the correction value acquisition operation is read from the RAM 268, and in step S23, the rotation detection amount that should actually be obtained from the rotation detector 22 from the correction value d and the rotation detection amount Ne. (Output value) Nf
To calculate.

In step S24, the control output for obtaining the rotation detection amount Nf is output from the I / O 262, and the drive device 28 drives the motor 10. Rotation detection amount Nf
Is the amount of rotation of the pulley 12 by the motor 10. Even if the rotating shaft of the motor 10 is connected to the pulley 12 via the gear mechanism, this relationship is not affected at all.

In step S25, the rotation of the motor 10 is monitored until the rotation amount Nf is obtained by the rotation detector 22, and when the rotation amount Nf is obtained, the process proceeds to step S26 to stop the rotation of the motor 10. , The correction control ends. Such rotation amount control is performed at any time during rotation transmission by the pulleys 22 and 24, and contributes to rotation transmission accuracy.

Table 2 shows the experimental results when such a rotation amount control is performed.

[0039]

[Table 2]

Table 2 shows the standard value, minimum value, maximum value and its correction value d of the rotation amount of the pulley 14 when the correction rotation operation at 100 rotations of the pulley 12 is not performed, and when the correction rotation operation is performed. The amount of rotation of the pulley 14 is shown. As is clear from this result, the deviation of the rotation amount of the pulley 14 with respect to the pulley 12, that is, the rotation amount error is reliably compensated, the accuracy of the rotation amount is improved, and this contributes to the improvement of the transfer accuracy of the transferred object 8. It is clear that this will be done.

In the embodiments, specific numerical values are given for simplification of description. However, in the carrying device of the present invention, the relationship between the first and second pulleys is the number, size and diameter. Is established irrespective of the magnitude relationship of the above, and is not limited to the example.

Further, in the embodiment, the ROM 266 and the RAM 268 incorporated in the control device 26 are used as the storage means, but this is because the control device 26 uses a microcomputer as an example. The external storage device may be installed separately, or when the host computer is installed and controlled, the storage device on the host computer side may be used.

[0043]

As described above, according to the present invention,
By compensating the decrease in the accuracy of the rotation ratio due to the tolerance in the diameters of the first and second pulleys, it is possible to transmit the rotation amount with high accuracy, avoid the error of the amount of transfer, and move the transferred object to the desired position with high accuracy. Can be transported to.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a carrying device of the present invention.

FIG. 2 is a flowchart showing correction value acquisition control in the transport apparatus shown in FIG.

FIG. 3 is a flowchart showing a correction value acquisition control following the flowchart of FIG.

FIG. 4 is a flowchart showing a rotation amount correction control in the transport apparatus shown in FIG.

FIG. 5 is a diagram showing an example of a conventional pulley device.

[Explanation of symbols]

 2 Conveyor Rollers 4 Conveyor Rollers 6 Conveyor Belts 8 Conveyed Objects 10 Motors (Drive Sources) 12 Pulleys (First Pulleys) 14 Pulleys (Second Pulleys) 16 Belts 22 Rotation Detectors (First Rotation Detection Means) 24 Rotation detector (second rotation detection means) 26 Control device 266 ROM (storage means) 268 RAM (storage means)

Claims (1)

[Claims] 1. A transport device for transporting an object to be transported by a transport belt suspended between a pair of transport rollers, the first pulley rotating by receiving a rotational force from a drive source, and the first pulley. A second rotation pulley that receives rotation via a belt suspended between the first pulley and a second rotation detection unit that detects rotation of the first pulley; Second rotation detecting means for detecting rotation of the second pulley, and a rotation amount of the second pulley to be obtained with respect to a predetermined rotation amount of the first pulley detected by the first rotation detecting means. And the second obtained from the second rotation detecting means.
Calculation means for calculating a correction value from the difference between the detected rotation amount of the pulley and the storage means for storing the correction value obtained by the calculation means, and the rotation amount to be obtained by the second pulley. The rotation amount to be set in the first pulley is corrected by the correction value read from the storage means according to the rotation transmission ratio between the first and second pulleys, and the drive source is set so as to obtain the rotation amount. A conveyance device comprising: a control unit for controlling.