JP3162155B2 - Position adjustment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, processing a precision element part such as a computer head to a predetermined size when a feature point of a work is positioned at a desired position from a reference plane at a high speed and with high accuracy. The present invention relates to a position adjustment method using a suitably applicable two-axis position adjustment device.

[0002]

2. Description of the Related Art In recent years, there has been a demand for high-precision processing and reduction in unit price of element parts of precision equipment. ing.

A conventional technique for positioning a characteristic point of a work such as a computer head at a desired position from a processing reference plane will be described below as an example.

FIG. 6 (a) shows a bar-shaped work, which has a cross-sectional shape as shown in FIG. 6 (b). In FIG. 6, 1 is a work, 2 is a feature point of work 1, BD
Is the dimension from the lower surface of the work (reference plane of the work) to the feature point 2, FD is a dimension required for the characteristics of the product, and is a finally required dimension after processing.

FIG. 7 shows an outline of the prior art. In FIG. 7, reference numeral 3 denotes a microscope for observing the end face of the work 1, and reference numeral 4 denotes a measuring jig. 5 is a processing jig, H is the height of the processing jig 5 which is a known amount, and L _1A and L _1B are desired positioning dimensions.

The operation of the conventional positioning technique having the above configuration will be described below. First, the BD on one end face of the work 1 is measured using the microscope 3, the BD is turned upside down, and the BD on the other end face is measured.
Is ranked. Next, the work 1 classified into the same rank is adhered and fixed using wax or the like in a state where the work 1 is aligned with the processing jig 5 so that the characteristic points 2 of each work 1 are predetermined on the lower surface of the processing jig 5. After that, the upper surface of the work 1 is processed in order to finally obtain the FD which is the required dimension.

[0007]

However, in the above-described configuration, the measurement and the attachment and fixing are completely separated steps, so that time is required, and the measurement accuracy, the jig height accuracy, and However, there is a problem that the positional accuracy of the characteristic points is reduced due to the variation in the amount of the applied wax.

In view of the above-mentioned conventional problems, the present invention provides a position adjustment that can perform a position adjustment of a work with high speed and high accuracy when positioning feature points on both end surfaces of the work with respect to a processing jig. The aim is to provide a method.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a two-axis tool for abutting and positioning a workpiece, a tool axis drive unit for feeding each tool to a designated position, and imaging of both ends of the workpiece. A pair of image pickup units, a visual recognition unit that inputs a video signal from each image pickup unit and measures the position of the work, a tool feed amount calculation unit that determines a tool feed amount, and a tool based on the determined feed amount. A method of adjusting the position of a work so that both ends thereof are at predetermined positions using a two-axis position adjusting device including a command control unit that outputs a command to an axis driving unit. The image of both ends of the work is captured by the unit, and the visual recognition unit recognizes the positions of both ends of the work based on this, and calculates the tool feed amount based on this position information and the information on the behavior of the work based on the change in the position of each tool. Means The command control means outputs a command to the tool axis drive unit based on the determined tool feed amount, drives each tool synchronously based on the command, and then drives both ends of the work. Perform a position recognition operation, repeat these series of operations until it enters the coarse adjustment range, in the fine adjustment process after entering the coarse adjustment range,
The tool feed amount calculating means determines the tool feed amount based on only the position information of both ends of the work by imaging and recognition, and drives each tool asynchronously based on the determined tool feed amount, and captures an image for each drive. , And a series of these operations are repeatedly performed until the operation enters the fine adjustment range.

[0010]

According to the present invention, the work is positioned by contact with a two-axis tool sent to a designated position, and the position information of the feature point detected by visual recognition and the two-axis In consideration of the effect of the behavior of the tool on the position of feature points on both end faces of the work, it is possible to calculate the tool feed amount by the tool feed amount calculation means and to position the tool, etc. Positioning of both ends of the work can be performed at high speed and with high accuracy.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described with reference to FIG.

In FIG. 1 showing the configuration of the two-axis position adjusting device of the present embodiment, reference numeral 1 denotes a bar-shaped work as shown in FIG. 6, and reference numeral 5 denotes a processing jig. Reference numeral 6 denotes a tool A that contacts one end of the work 1, and reference numeral 7 denotes a tool B that contacts the other end of the work 1.

Reference numerals 8 and 9 denote linear motion positioning for sending the tool A6 and the tool B7 to designated positions in order to change the position of each end of the work 1 based on the contact between the work 1 and the tool A6 and the tool B7. A part A and a linear positioning part B. Reference numerals 10 and 11 denote a tool axis position detector A and a tool axis position detector B in the linear motion positioning section A8 and the linear motion positioning section B9. Numerals 12 and 13 denote an imaging unit A and an imaging unit B which look at each end face of the work 1 and image it. 1
Reference numerals 4 and 15 denote a visual recognition unit A and a visual recognition unit B that input video signals from the imaging unit A12 and the imaging unit B13 and measure the positions of feature points. Reference numeral 16 denotes a position for positioning the work 1 at a predetermined position based on position information from the visual recognition unit A14 and the visual recognition unit B15 and information on behavior of the work 1 based on a change in position of the tool A6 and the tool B7. Tool feed amount calculating means for determining the tool feed amount of
Reference numeral 7 denotes a command control unit that outputs a drive command based on the determined feed amount. Reference numerals 18 and 19 denote positioning control means A and positioning control means B which process signals from the tool axis position detector A10 and tool axis position detector B11 and drive command signals from the command control means 17, respectively. 20 and 21
Are positioning control means A18 and positioning control means B19.
The linear motion positioning part A10 and the linear motion positioning part B1
1 is a linear motion positioning section driving means A and a linear motion positioning section driving means B which drive the motor 1.

FIG. 2A shows how the position of the work 1 is regulated. The work 1 is composed of a tool A6 using a main body 5a of a processing jig 5 and two pairs of regulating claws 5b urged by a spring 5c. The position is regulated so that the position can be adjusted only in the axial direction of the tool B7. FIG. 2B shows the end surface of the work 1 viewed from each direction. In FIG. _2B , L _2A and L _2B are desired positioning dimensions.

The operation of the two-axis position adjusting device configured as described above will be described. First, the visual recognition unit A14 and the visual recognition unit B15 measure the initial position of each feature point on both end faces of the work 1, and the deviation amount of each feature point from the target value and the interference effect due to the position change of the tools 6 and 7 (later The feed amount of each of the tools 6 and 7 is determined on the basis of (detailed description), and the linear motion determining unit A8 and the linear motion positioning unit B9 are driven synchronously to perform coarse adjustment until the coarse adjustment is completed. Repeat this. Next, the process proceeds to fine adjustment. Here, the linear movement positioning unit A8 and the linear movement positioning unit B9 are asynchronously driven based on the determined feed amount without considering the interference effect, and the fine adjustment is performed until the fine adjustment is completed. repeat.

Here, the synchronous drive and the asynchronous drive at the time of each adjustment determined by the command control means 17 will be described with reference to the flowchart of the adjustment operation shown in FIG. 3 and the operation chart shown in FIG. The position measurement of the feature point is performed every time the tools 6 and 7 are sent to the designated positions. However, even if the position of the other feature point is measured while one of the tools is being driven, the interference will not occur. The effect shifts the position of the feature point, so that the accuracy of the measured position information is lost. Therefore, when performing the adjustment in consideration of the interference effect, the position measurement of the feature point is performed after the driving of both tools is completed.
After both measurements are completed, it is necessary to drive both tools 6 and 7 (synchronous drive). On the other hand, when the adjustment is performed in a range where the interference effect can be ignored, a series of loops from position measurement to tool driving can be performed independently on two axes (asynchronous driving). As described above, in the present embodiment, the work position adjustment operation is divided into two stages of coarse adjustment considering the interference effect and fine adjustment not considering the interference effect in order to reduce the adjustment time. Synchronous drive and asynchronous drive for fine adjustment. It goes without saying that the adjustment operation taking into account the interference effect may be performed consistently without providing a distinction between the coarse adjustment range and the fine adjustment range. When the adjustment is completed as described above, the desired positioning is completed by attaching and fixing the work 1 to the processing jig 5.

Next, the operation of the tool feed amount calculating means 16 for determining the tool feed amount during the coarse adjustment and the fine adjustment will be described. Figure 5 shows the geometric positional relationship between the end face of the tool 6 and the workpiece 1 in the present embodiment, in FIG. 5, the feed amount of X _B tool B7, Y _A tool B7
The moving distance of the tool A6 side of the feature points associated with the movement, Y _B is the tool B7 side travel distance of the feature points, also the broken line work 1 before moving in tool B7 of the workpiece 1 and the tool 6 state, the solid line is the state of the work 1 assuming a workpiece 1 actual state after moving the tool B7, and one-dot chain line tools A6 was also moved by X _B. As is clear from this figure, when the feed amounts of both tools 6 and 7 are different, the moving distance of each feature point is determined by the corresponding tool 6 and
Does not match the feed rate of 7 deviates it can be seen (referred to as an interference effect this herein, mutual interference of the following Y _A, Y _B
Is called self-interference). When performing coarse adjustment, both the mutual interference and self-interference cannot be neglected because the feed amount of the tool becomes large. In this embodiment, each interference amount is considered to be a function of the tool feed amount. feed amount X _a, and X _B were determined as follows. Current position P _A of the two feature points, P _B and the difference between the target value M ₀ Δ _A, if _{Δ B, X A = Δ A} + f A (X A, X B) X B = Δ B + f B (X _A , X _B ) where Δ _A = M ₀ −P _A , Δ _B = M ₀ −P _B f _A (X _A , X _B ) = α _A · X _A + β _A · X _B f _B ( _{X a, X B) = α} B · X a + β B · X B α a, α B, β a, a beta _B = constants.

In this embodiment, a linear equation is used for simplification.

On the other hand, when the fine adjustment is performed, since the feed amount of the tool becomes small, mutual interference and self-interference can be ignored without causing a substantial problem. Accordingly, the feed amount of each tool at the time of fine adjustment is used the delta _A, the delta _B as it is.

As described above, according to the present embodiment, the linear motion positioning portions A8 and B9 for feeding the tool to the designated position.
Based on the tool axis position detectors A10 and B11 attached thereto, the linear motion positioning unit driving means A20 and B21 for driving them, and the signals of the tool axis position detectors A10 and B11 and the tool feed amount. A tool axis drive unit including positioning control means A18 and B19 for processing a drive command signal, an imaging unit A12 and B13 for viewing the end surface of the work 1 whose position is regulated by the processing jig 5, and a video signal from them. Based on the visual recognition units A14 and B15 for inputting and measuring the position of the work 1, position information of the work 1 therefrom and information of the behavior of the work 1 by positioning the tools 6 and 7 in contact with each other. A tool feed amount calculating means 16 for determining a tool feed amount for positioning the work 1 at a predetermined position, and a positioning control based on the determined feed amount. It is provided with the instruction control unit 17 for outputting a drive command to the means A18 and the B19, the processing jig 5
By measuring the position of the characteristic point of the work 1 with respect to the position, and performing the coarse adjustment for predicting the interference effect and adjusting the synchronous position, the position is adjusted in two stages of fine adjustment ignoring the interference effect. High-speed and high-accuracy positioning can be performed.

In this embodiment, the position of the workpiece is adjusted based on the contact with the tool.
The positioning was completed by pasting and fixing to the processing jig.However, the jig to which the workpiece was pasted in advance was structured so that the position could be adjusted by the screw feed mechanism, and the bit shaft that transmits rotation to the feed screw as a positioning part A configuration employing a rotary positioning mechanism may be employed.

[0022]

According to the present invention, by providing the tool axis driving unit, the imaging unit, the visual recognition unit, the tool feed amount calculating means, and the command control means as described above, the position to be obtained can be determined. Positioning can be performed while measuring directly, high-precision positioning can be performed without being affected by variations in bonding accuracy, etc. In addition, interference effects can be predicted during position adjustment based on information from the recognition device. In order to adjust the synchronous position, the workpiece can be positioned at high speed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a two-axis position adjusting device according to an embodiment of the present invention.

FIGS. 2A and 2B show a state of work position regulation in the embodiment, wherein FIG. 2A is a perspective view, and FIG. 2B is a view of a work end face viewed from each direction.

FIG. 3 is a flowchart of an adjustment operation in the embodiment.

FIG. 4 is an operation chart in the embodiment.

FIG. 5 is an explanatory diagram of a geometric positional relationship between a tool and a work end surface in the embodiment.

6A and 6B show a shape of a work, FIG. 6A is a perspective view, and FIG.
Is a sectional view.

FIG. 7 is an explanatory view of a position adjusting step of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work 5 Processing jig 6 Tool A 7 Tool B 8 Linear positioning part A 9 Linear positioning part B 10 Tool position detector A 11 Tool position detector B 12 Imaging part A 13 Imaging part B 14 Visual recognition part A 15 Visual recognition unit B 16 Tool feed amount calculation unit 17 Command control unit 18 Positioning control unit A 19 Positioning control unit B 20 Linear positioning unit driving unit A 21 Linear positioning unit driving unit B

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G05D 3/00-3/20 G05B 19/18-19/46

Claims (1)

(57) [Claims] 1. A two-axis tool for abutting and positioning a workpiece, a tool axis drive unit for sending each tool to a designated position, and a pair of imaging units for imaging both ends of the workpiece.
And visual recognition unit for measuring the position of the workpiece to input the video signals from the imaging unit, and tools feeding amount calculating means for determining a tool feed rate, relative to the tool axis driving unit based on the determined feeding amount 2 provided with command control means for outputting a command.
Use a shaft position adjustment device to move the work
This is a method of adjusting the position so that
In this case, both ends of the workpiece are imaged by a pair of
The position of both ends of the work is recognized by the visual recognition
Behavior of Work Based on Position Information of Tool and Position Change of Each Tool
The tool feed amount calculation means based on the
Determine the feed rate and command based on the determined tool feed rate.
The control means outputs a command to the tool axis driving section,
Drive each tool synchronously based on the
Performs recognition of the positions at both ends and coarsely adjusts a series of these operations.
Adjustment until it enters the coarse adjustment range.
In the fine adjustment process that follows,
The tool feed amount calculation means is based on only the end position information.
Tool feed rate, and based on the determined tool feed rate,
Drive each tool asynchronously, and capture and recognize each drive
And repeat these series of operations until they enter the fine adjustment range.
A position adjustment method, which is performed by returning.