JPS644854B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a frame bender control method capable of automating frame bending.

Conventionally, when bending a frame in its longitudinal direction, a frame bender is used, clamping two points separated by a predetermined distance, and applying bending force to the intermediate portion to perform the bending process.

In this case, the bending angle is completely controlled by marking the frame, which is the workpiece, in advance with a curve that is in the opposite direction to the processing state after bending, and the operator visually operates the frame bender so that this curve becomes a straight line. It was a manual operation.

For this reason, the time required for marking is long and complicated, the working efficiency is low, and there are disadvantages such as low machining accuracy such as uneven machining.

It is an object of the present invention to eliminate such conventional drawbacks and provide a method for controlling a frame bender that can automate frame bending. The structure of the present invention that achieves this object is to support a workpiece being fed in the longitudinal direction at two points separated by a predetermined distance, and to bend the workpiece by applying a constant displacement perpendicular to the longitudinal direction to the middle part of the supporting points. When machining, always measure the distance from the reference line along the feed direction to the displacement point, and the distance from the midpoint between the displacement point and the support point, and from these measured values The bending angle to be obtained is calculated in advance, the workpiece is fed to a position where the bending angle matches the target bending angle to be applied to the workpiece, and the bending process is performed by applying the constant displacement to each feeding stop position. It is characterized by the following.

Hereinafter, one embodiment of the method of the present invention will be described in detail with reference to the drawings.

1 and 2 are a plan view and a front view of a bending section of a frame bender to which the frame bender control method of the present invention is applied.

The frame bender has a frame 1, which is the workpiece.
(In the illustrated example, scalene angle steel is shown.) In order to feed the steel in the longitudinal direction (a-b direction in the figure), feeding rollers 2 and 3 are provided at the front and rear.
direction), and the frame 1 can be sent by rotationally driving the feed rollers 2 and 3 at the upper position g. In order to clamp the frame 1 sent in this way, clamping mechanisms 4, 5, and 6 are provided at two locations at the front and back, which are separated by a predetermined distance, and at the center thereof, each of which is equipped with a fluid pressure cylinder that clamps the frame 1 by vertically clamping it. inner frame 1
to clamp. In addition, the front and rear clamp mechanisms 4,
Attached to 6 are fulcrum blocks 4a and 6a which serve as fulcrums P ₁ and P ₅ during bending. On the other hand, the central clamping mechanism 5 is movable in the width direction of the frame 1 (perpendicular to the longitudinal direction: c-d direction), and furthermore, together with the central cylinder 7 that is slidable in the width direction of the frame 1, the frame 1 Bending force and displacement can be applied to perform bending, inward bending or outward bending.

In addition, in order to detect the width direction displacement of the frame 1 in the clamped state before processing, the degree of bending during bending, and the state after bending is completed, the positions P ₁ and P ₅ of the front and rear clamp mechanisms 4 and 6 are determined. Length measuring device 8,
9 is provided, as well as front and rear clamp mechanisms 4,
6 and the respective fulcrums P ₁ of the central clamping mechanism 5,
Length measuring devices 8a and 9a are provided at intermediate points P ₂ and P ₄ of P ₅ or the point of action P ₃ , respectively, and output the displacement electrically. Also, a wavelength meter 10 is installed at the rear end of the central cylinder 7 to measure the displacement applied during bending.
are provided, and these five length measuring devices 8, 8a,
9, 9a, 10 indicate the bent state of frame 1, etc.
The displacement of the point in the width direction with respect to the reference position can be measured. Furthermore, a frame displacement measuring device 11 is provided inside the central cylinder 7 and is brought into contact with a side portion of the frame 1 to measure the amount of movement of the central cylinder 7 as well as the amount of bending of the frame 1 . Further, in order to detect the feed amount in the longitudinal direction of the frame 1, a feed amount detector 12 is provided linked to a fixed part of the machine (not shown). line) frame 1 along the lc
However, depending on the shape of the frame, it can be slid so that it is always positioned on the bending center line.

In bending with a frame bender having such a structure, the bending amount C 1 when bending is performed from a certain state, for example, a straight state or a slightly bent state, to a target bending angle θ _T , that is, the bending amount C ₁ of the central cylinder 7. It is necessary to know the amount of displacement C ₁ in advance.

Therefore, as shown in FIG. 3, the relationship between the target bending angle θ _T and the bending amount C ₁ is determined using a bending model. In this model, after bending the intermediate part F of an unprocessed straight frame to an angle θ ₀ , the frame is sent and the point H is bent at an angle θ _T (target bending angle).
This shows the case where you try to bend only.

In the bending model shown in the figure, the left and right clamp points A and E are supported by pins with no restraining force, and the central cylinder point C is supported with restraint as a prerequisite for the process.

Based on this precondition, we can understand the following.

○B By pushing at point C, the length of the member in sections A to E is extended, but this elongation is provided from the left of point A or the right of point E, and the member itself does not expand or contract in the longitudinal direction.

○B The left and right sides of point C are completely independent, and there is no movement of point C from right to left or vice versa.

Based on the above relationship, when bending point H, the following relational expression holds true.

θ _T = θ _L + θ _R …(1) θ _L = θ ₃ +θ ₄ +θ ₆ …(2) Here, θ ₆ =∠ALC θ ₃ +θ ₄ =∠FHP≡∠JLA≡∠F′LP′ In other words, the angle θ ₀ at point F does not change even when the point H is bent, and therefore △AFH≡△A′F′L.

At the same time, the member length is increased by bending from H to L.
AFH changes to AJL, and this growth is from the left of point A.
r ₀ will be provided.

AFH+r ₀ =AJL Therefore, the angle created by this length extension is θ ₃ . Therefore, in drawing, first, △AFH
Create ≡△A′F′L, find a point P′ on the extension of A′F′ where AL=P′L, rotate this triangle △P′F′L around L, and calculate △AJL(≡P 'F'L) is the shape when H is bent to L.

Here, since θ ₃ can generally be ignored in a range where the pressing amount (L-H) is small, θ _L θ ₄ + θ ₆ ...(3) Also, θ ₄ θ ₁ + tan ^-1 2 (b ₀ - C ₀ ) /l ₁ θ ₁ +2(b ₀ −C ₀ )
/l ₁ C ₀ /l ₁ +2(b ₀ −C ₀ )/l ₁ 2b ₀ −C ₀ /l ₁ …(4)
This equation (4) shows that point F is from B to C as shown in Figure 3.
If it is outside the range, draw an auxiliary line from point H parallel to AC and _take point A _″ on _that line ^. ₀ )×2/l ₁ ∴θ ₄ =θ ₁ +θ ₁ ′=θ ₁ +tan ⁻¹ 2(b ₀ −C ₀ )/l ₁ holds true. Here, θ ₁ ' is the angle ∠ between G and a straight line A'' passing through H and parallel to AC, as shown in Figure 4.
Indicates A″HG.

On the other hand, if point F is within the range of B to C,
As extracted and shown in Figure 4, when point G is taken on AF, it is approximated by θ ₁ ′=∠FHA″∠GHA″, so θ ₄ is generally expressed as (4)
It will be expressed by the formula.

Also, θ ₆ =∠ALC=π/2−tan ^-1 (C _S /l ₁ )π/2−C ₃ /l
₁ ...(5) Therefore, θ _L 2b ₀ −C ₀ /l ₁ +π/2−C _S /l ₁ =π/2+2b ₀ −C ₀
−C _S /l ₁ ...(6) θ _R can be calculated in exactly the same way as θ _L from the above preconditions.

θ _R π/2+2d ₀ −C ₀ −C _S /l ₁ ...(7) The resulting required bending angle θ _T is θ _T =θ _L +θ _R π/2+2b ₀ −C ₀ −C _S /l ₁ +π/2+2d
₀ −C ₀ −C _S /l ₁ =π+2(b ₀ +d ₀ −C ₀ −C _S )/l ₁ ...(8)
becomes.

∴C _S = (π-θ _T )×l ₁ /2 + b ₀ + d ₀ − C ₀ ...(9) C ₁ = C _S −C ₀ ≒l ₁ /2 (π-θ _T ) + b ₀ + d ₀ − The relational expression 2C ₀ ...(10) is obtained.

Here, l ₁ is a unique value determined by the frame vendor, b ₀ , C ₀ , and d ₀ are the widthwise displacements of the state of frame 1 before bending from the reference line,
The length measuring instruments 8, 8a, 9, 9a, and 10 are brought into contact with the frame 1, respectively, and b ₀ , C ₀ , before and after contact are made.
This is a value that can be measured from the change in the rate of change of _d0 .

Therefore, if the target bending angle θ _T is given, the necessary bending amount C ₁ can be calculated, and conversely, if the bending amount C ₁ is given, the bending angle θ _T can be calculated.

Therefore, in the actual bending process, the displacement for each fixed length shown in the production drawing as shown in FIG. 5 is used as input data.

The control system for controlling the frame bender includes length measuring devices 8, 8a, 9, 9 for measuring the initial state of the frame, as shown in FIG.
The signal from a, 10 is input to the length measuring device input section 20, and is input to the bending amount calculation section 22 via the measured value processing section 21. Further, bending data read from the production drawing is input to the bending data input section 24, and is inputted to the bending amount calculation section 22 via the bending data processing section 23. Further, the absolute position of the frame, that is, the frame feed amount is detected by the feed amount detector 12 and inputted to the feed amount input section 25, sent to the bending data processing section 23, and also inputted to the feed control section 26. The output signal from the bending amount calculation section 22 is inputted to the bending control section 27 via the bending position determining section 30, and the central cylinder 7 is controlled via the drive control section 29. It is also input from the bending position determination section 30 to the feed control section 26, and this feed control section 26
The output signal from the alignment clamp control section 28 is also sent to the drive control section 29, and is also connected to the bending control section 27 and the alignment clamp control section 28, so that the output signal of the alignment clamp control section 28 is also sent to the drive control section 29. .

In actual machining, first, each data such as i=0 to i=4 in FIG. Start.
During this feeding control, each measuring length device 8, 8a, 9, 9
a, 10, the frame displacement measuring device 11, and the feed amount detector 12, and the stored value of the bending data processing section 23, the bending amount calculation section 22 calculates the necessary bending amount _C1 using the above formula. When the central cylinder 7 reaches a certain extrusion amount, the bending position determination section 30 determines that the feeding of the frame is stopped, and the alignment clamp control section 28 aligns and clamps the frame, and then the central cylinder 7 is pushed out a certain amount. Protrude and bend. thus,
Amount of bending required for a constant amount of extrusion of the central cylinder 7
All processing is completed by sending the frames sequentially and bending them until C ₁ matches.

The required bending amount C ₁ can be calculated using the above formula by converting the values b ₀ , C ₀ , and d ₀ from the results of each length measuring device, and the target bending angle can be calculated using the interpolation method from the bending data. Accordingly, the total bending angle within the feed section where bending control is performed can be obtained from the bending data processing unit 23 as a value at the absolute position of the frame, and is used to calculate the bending amount.

As described above in detail with the embodiments, according to the present invention, the target bending angle θ _T matches a constant extrusion amount (constant bending amount) using the relationship between the target bending angle θ _T and the bending amount C ₁ By sending the frame in such a way, you can easily bend the frame. Furthermore, regardless of the size of the bending angle, the bending process is performed by a set constant bending amount, so that the process can be performed with constant accuracy.

Furthermore, when compared with deep bending where the amount of bending is variable, the accuracy is improved, and in the case of shallow bending, the feed pitch can be increased, so the machining time can be shortened. As described above, according to the method of the present invention, bending by a frame bender can be automated.

[Brief explanation of drawings]

1 and 2 are a plan view and a front view of the bending section of a frame bender to which the frame bender control method of the present invention is applied, and FIGS. 3 and 4 are explanations showing a modeled frame bending process. figure,
Figure 5 is an explanatory diagram of input data for bending processing, Figure 6
The figure is a block diagram of the control system of the frame vendor. In the drawing, 1 is a frame, 2 and 3 are feed rollers,
4, 5, 6 are clamp mechanisms, 4a, 6a are fulcrum blocks, 7 is a central cylinder, 8, 8a, 9, 9
a, 10 is a length measuring device, 11 is a frame displacement measuring device,
12 is a feed amount detector, and θ _T is a target bending angle.

Claims (1)

[Claims] 1. When a workpiece being fed in the longitudinal direction is supported at two points separated by a predetermined distance and a constant displacement is given to the middle part of the supporting points at right angles to the longitudinal direction for bending, a reference line along the feeding direction is used. The distance from A frame bender characterized in that the workpiece is fed to a position where the angle matches a target bending angle to be applied to the workpiece, and the bending process is performed by applying the constant displacement at each feeding stop position. Control method.