JPH0236337B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention can be used as a feeding device for feeding materials for machine tools in various production sites such as press machines, and
The present invention relates to a roll feeder used as a product conveyance device, and particularly to a control device for a roll feeder with enhanced monitoring functions.

[Prior art]

A roll feeder is one of the means for supplying materials to be transported to a press machine or the like. This roll feeder is a device that has a pair of upper and lower rolls, inserts and clamps the material to be transported between the rolls, rotates these rolls at a predetermined angle, and supplies the material intermittently by the frictional force of the rolls. .

FIG. 4 shows an example in which a roll feeder is used as a feeding device of a press machine. 1 in the figure is a roll feeder, which has a pair of upper and lower rolls 1a,
1b, and a control motor 1c is used as a drive source. Reference numeral 2 denotes a roll feeder control device for setting the feed amount and feed speed of the material. Furthermore, 3 is a press machine, and 4 is a mold attached to the press machine 3. Reference numeral 5 denotes a press machine control device that sets the rotation speed of the press machine 3, and controls the rotation speed of the press machine 3 from the rotary cam of the press machine 3, the pilot pin provided on the mold 4, etc. (not shown).
Upon receiving synchronization signals and alarm signals, these signals are sent to the roll feeder control device 2.
Based on this synchronization signal, roll feeder 1:
Material is intermittently supplied into the mold 4 in accordance with the movement of the ram of the press 3. In addition, in the figure, 7 is a loop sensor, and 8 is a material rewinding device.

In this way, when the control motor 1c is used as the drive source of the roll feeder 1 and numerically controlled, the feed amount and feed speed of the material can be easily adjusted, and compared to when the power of the press machine 3 is also used. The setup time for the adjustment work can be significantly shortened, and its use has been expanding in recent years.

By the way, the press machine 3 and roll feeder 1 are
Accurate press processing can only be performed with accurate synchronization. In other words, the feeding capacity of the roll feeder 1 is
If the press machine 3 cannot keep up with its working capacity, accurate press processing cannot be performed, and if the press machine does not have an alarm stop function, it may cause damage to the mold 4. Furthermore, even if the press has an alarm stop function, the press operation must be interrupted.

Therefore, during press working, the rotation speed of the press machine 3 must be set so as not to exceed the maximum number of feeds per unit time (hereinafter referred to as SPM) of the roll feeder 1.

By the way, the SPM of the roll feeder 1 is determined by the feed length of the material that can be fed at one time, the maximum value of the feed speed, the acceleration during acceleration/deceleration, and the possible time of the feed operation in one cycle of press working (generally In the roll feeder 1, if the top dead center of the ram of the press machine 3 is 0°, the material is fed within a rotation angle of about 240° to 0° to 120° with respect to the rotation direction of the rotary cam), etc. determined by.

Conventionally, to obtain this SPM, as shown in Figure 5, the maximum value of the feed rate and the acceleration during acceleration/deceleration are set to constant conditions, and the SPM that shows the relationship between the feed length and SPM under those conditions is calculated. A common method is to read from a curve diagram. In addition, Figure 5 shows two types of SPM curve diagrams with different feeding conditions.
If the feeding conditions differ, as many SPM curve diagrams are required.

However, in recent years, as the trend toward high-mix, low-volume production has increased, the number of products produced for one set of molds (mold life) has been decreasing. Furthermore, as product shapes become more complex and higher precision is required, multiple stamping steps are required to complete the product. Therefore, various molds are required, and the number of times the molds are replaced has increased.

On the other hand, the feed length of the material is determined according to each mold, and the upper limit of the maximum feed rate and acceleration/deceleration is determined depending on the type of material being fed, the processing purpose of the mold, etc. ing. In order to better satisfy these feeding conditions, the control function of the roll feeder has been improved, and roll feeders with variable maximum feed speed and acceleration during acceleration and deceleration are now available on the market.

[Problem to be solved by the invention] However, when it becomes possible to set a number of feed conditions for the roll feeder, when calculating the SPM of the roll feeder from the SPM curve diagram shown in FIG.
An SPM curve diagram corresponding to the feeding conditions is required. For example, if there are 9 types of maximum feed speed and 5 types of acceleration during acceleration/deceleration, there will be 45 types of SPM curve diagrams. Among these many SPM curve charts, one must find one that meets the feeding conditions and read the SPM of the roll feeder. Also,
Each time the mold is replaced, the feed conditions of the roll feeder change, so it is necessary to read the SPM of the roll feeder again, set the rotation speed of the press to a lower value, and start work. Therefore,
As the feed function of the roll feeder increases, it takes time to set the rotation speed of the press machine, and as the number of mold changes increases, the number of settings increases, increasing the setup time for press work. There was a problem.

In addition, when setting the rotation speed of the press machine, another method is to set it by the operator based on experience, or to lower the rotation speed of the press machine and then gradually increase the rotation speed to increase the feed rate of the roll feeder. There is also a method of determining the point at which the press machine cannot follow the rotation speed of the press machine (determined by an alarm function, etc.), setting the press machine rotation speed below that point, and then starting the pressing operation. However, in the former case, the rotational speed of the press machine is inevitably set roughly, making it impossible to perform efficient work. Furthermore, the latter method has a problem in that setup time is required to set the rotation speed of the press.

[Structure of the invention]

The present invention was made in view of the above-mentioned problems, and it is possible to improve the performance of the roll feeder under various feeding conditions.
The aim is to instantly calculate and display the SPM (maximum number of feeds per unit time) and set the press machine's rotation speed to the optimal rotation speed based on this SPM, thereby reducing the setting time.

The configuration includes: a set value input means for setting feed conditions in the control device of the roll feeder; a control circuit that sends a control signal to the control motor based on the feed condition given through the set value input; The device is equipped with a calculation section that calculates at least the maximum number of times the roll feeder is fed per unit time based on the feed conditions given via the set value input means, and a display section that displays the calculation results of the calculation section. .

[Effect]

If you set the feeding conditions, based on the setting conditions,
The maximum number of times the roll feeder is fed per unit time is calculated, and the value is displayed on the display. Based on this value, the rotation speed of the press is set to the optimum value.

〔Example〕

The present invention will be explained in detail below using the drawings. FIG. 1 shows an embodiment of a roll feeder control device according to the present invention. The control device 20 can be roughly divided into an operation panel 21 for inputting feeding conditions;
Based on the input feed conditions, alarm signals and synchronization signals from the press machine, the controller section 22 generates control signals for the control motor of the roll feeder and calculates the SPM, etc. of the roll feeder, and the feed conditions, SPM, etc. a display device 23 for displaying images; a driver section 24 for actually controlling the rotation of the control motor based on control signals from the controller section 22;
Power unit unit 2 that controls power ON/OFF and exchanges signals between the press machine and the controller 22
5 and a case 26.

Further, the controller section 22, which is the gist of the present invention, will be explained in detail using the block shown in FIG.

The controller section 22 has a memory 31 that stores feed conditions input from the operation panel 21, such as feed length, number of feeds, feed speed, and acceleration during acceleration/deceleration for each mold.

The feed conditions input from the operation panel 21 are once stored in the memory 31 and then output to the control circuit 32. The control circuit 32 also controls the power supply unit 2 based on this feeding condition.
A control signal is generated to the control motor in response to a synchronization signal and an alarm signal inputted from the press machine 27 via the roll feeder 28, and controls the feeding, starting and stopping of the roll feeder 28. Further, by operating the operation panel 21, a start/stop signal for the press machine 27 is outputted from the control circuit 32 to the press machine 27 via the high-power unit section 25.

On the other hand, part of the feeding conditions stored in the memory 31, in this embodiment, the model number of the mold, the feeding length and the number of feeds corresponding to this model number are selectively displayed on the display device 23.

Further, the controller section 22 is provided with a calculation section 33. This calculation section 33 has a calculation circuit 33a that functionally calculates the SPM (maximum number of feeds per unit time) of the roll feeder, and the SPM calculated by this calculation circuit 33a or the actual measurement from the synchronization signal with the press machine 27. It consists of an arithmetic circuit 33b that calculates the remaining working time based on the SPM and the set number of feeds (number of presses).

Next, how does the arithmetic circuit 33a calculate SPM?
Calculate or explain. Actual roll feeder 2
8, the relationship between the feed speed and the feed time can theoretically be approximated by the three graphs shown in FIG. In each graph, it is assumed that the absolute values of acceleration and deceleration are equal.

Graph a (shown by a solid line) shows a case where the feed length is relatively long, and the roll feeder 28 is accelerated at a constant acceleration until the feed speed reaches the maximum speed, then moves at a constant velocity at the maximum speed, and then decelerates. This is when the feed operation is stopped. In addition, when the feed length becomes shorter, as shown in graph b (dashed line), the speed is accelerated at a constant rate, and immediately after reaching the set maximum speed, the feed operation is decelerated and the feed operation is stopped, as shown in graph c. In some cases, the speed may be decelerated before reaching the maximum speed.

Here, the time required for one cycle of press processing is S (min), and the maximum speed of the roll feeder is V.
(m/min), the absolute value of acceleration during acceleration/deceleration is A
(m/min ² ), and the length of one feed is L, L′, respectively.
L″ (m), time required for one feeding T, T′,
T″ (min), and the ratio of feedable time during one cycle of press processing is X, the maximum number of feeds per unit time SPM can be approximated by the following calculation formula.

First, a case will be described in which the feeding operation of the roll feeder 28 is approximated by graph a.

First, find the time T required for one feeding.
Let T ₁ (min) be the time of uniform motion, and the acceleration/
If the time required for each deceleration movement is T ₂ (min), then T = T ₁ + 2T ₂ (min)...

Further, the feed length L is L=(1/2)AT ₂ ² +VT ₁ +(1/2)AT ₂ ² =VT ₁ +AT ₂ ² (m)...

Also, the maximum speed V is V=AT ₂ (m/min)... Therefore, when substituted into the equation, L=VT ₁ +VT ₂ (m)... Further substituting the formula, L=V(T- _2T2 )+ _VT2 =V(T- _T2 )(m). Further substituting the formula gives L=V(TV/A)(m). If this formula is changed, the time T required for one feeding becomes T=L/V+V/A (min).

In addition, since the ratio of the feedable time during one cycle of press processing is set to X, the time S required for one cycle is: XS=T S=T/X=1/X(L/V+V/A )(min)
becomes.

If the time required for one cycle is found, the maximum number of feeds per unit time SPM can also be found.

SPM=1/S=X/(L/V+V/A), multiplying the numerator and denominator by VA, SPM=XVA/(LA+V ² )(number of times/min)...

Also, the possible feed time X during one cycle of press working is, for example, 2/3, so X = 2/3
In the case of , SPM=(2/3)・{VA/(AL+V ² )}(number of times/min)
It is approximated by

Similarly, in the case of graph b, the time required for acceleration/deceleration motion, _2T , is the time required for one feed motion.
becomes T′. Therefore, the feed length L' is: L'=1/2AT ₂ ² +1/2AT ₂ ² =AT ₂ ² (m) Substituting the formula, = VT ₂ (m) 2T ₂ = T', so the feed The length L' is L'=(1/2)・VT'(m).

Therefore, T'=2L'/V (min).

Also, since T'=XS', the time S' required for one cycle is S'=T'/X=(2L'/V)・(1/X)(min) =2L'/VX( min) Therefore, the maximum number of feeds per unit time
SPM is as follows: SPM=1/S'=VX/2L' (number of times/min)...

Also, as in the case of graph a, when X=2/3, SPM=V・(2/3)/(2L') =V/(3L') (number of times/min).

Furthermore, as in graph C, if the speed is decelerated before reaching the set maximum speed, the time required for acceleration/deceleration movement is 2T ₃ as in the case of graph B.
is the time T″ required for one feed operation. Therefore, the feed length L is calculated as follows: L″ = V′・T, where V′ is the feed speed when switching from acceleration to deceleration movement. It becomes ₃ .

Also, since V′=AT ₃ and T″=2T ₃ , L″=AT ₃ ² =(1/4)AT″ ² (m).

Therefore, T″=2(L″/A) ^1/2 (min).

Since T″=XS″, the time S″ required for one cycle is S″=T″/X=(2/X)(L″/A) ^1/2 (number of times/
min).

Therefore, the maximum number of feeds per unit time
SPM is as follows: SPM=1/S''=X/T''=(X/2)(A/L'') ^1/2 (number of times/min)...

Similarly to graphs a and b, when X=2/3, SPM=(1/3)(A/L″) ^1/2 (number of times/min).

From the above, the SPM of the roll feeder has the relationship between feed speed and feed time as shown in , In the case of graph a, SPM = XVA / (LA + V ² ) (number of times / min) In the case of the graph, SPM = VX /2L' (number of times/min) In the case of graph c, SPM = (X-2) (A/L'') ^1/2 (number of times/min). However, V is the maximum feed speed, and A is the acceleration/deceleration time. The absolute value of the acceleration, L, L′, L″ are the feed lengths,
X is the percentage of time available for feeding during one cycle of press working.

Further, X varies depending on the type of press working, etc., but is approximately 2/3 or less.

When X is 2/3, SPM is: For graph a, SPM = (2/3) {VA/(AL+V ² )} (number of times/min) For graph b, SPM = V/(3L') (number of times /min) In the case of graph c, it is expressed by the formula SPM = (1/3) (A/L'') ^1/2 (number of times/min).

On the other hand, when calculating SPM, it is necessary to determine which formula to use for calculation based on the set values of the feed conditions. As a criterion, it is determined in the arithmetic circuit 33a whether the relationship between the feed speed and the feed time corresponds to graph b.

In other words, in the case of graph b, as mentioned above, the feed length L' is expressed as L' = V (1/2) T' (V: maximum feed speed, T: time required for one feed). is,
Further deformation results in L'=V ² /A (A is acceleration during acceleration/deceleration). Based on this relational expression, the feed length L' is calculated from the acceleration A and the maximum feed speed V set as feed conditions. Feed length of this calculated value
L′ and the actual feed length set as the feed condition
Examine the relationship with L ₁ . And if L ₁ > L′, then
The relationship between feed speed and feed time is graph a,
If L ₁ = L', the graph will look like b, and if L ₁ <L', the graph will look like c.

Thus, by selecting an SPM calculation formula that meets the feed conditions, it is possible to obtain the SPM under the set feed conditions. The SPM calculated in this way is
A slightly smaller value is displayed on the display device 23, allowing for a slight error. Then, the operator looks at the SPM of the roll feeder, sets the rotation speed of the press machine 27 (the number of presses per unit time), and starts the press operation. Furthermore, when the press operation is started, the actually measured number of feeds per unit time is displayed on the display device 23 based on the synchronization signal from the press machine 27 instead of the calculated SPM.

On the other hand, the calculation circuit 33b calculates the remaining working time based on the SPM calculation result and the number of times of feeding (the number of presses) set as the feeding condition. In addition, when the press operation actually starts, the calculation circuit 33b measures the actual number of feeds per unit time based on the synchronization signal from the press machine,
The remaining work time is calculated based on this measured value. The remaining working time calculated by the arithmetic circuit 33b is displayed on the display device 23 along with the SPM of the roll feeder.

Therefore, if the operator sets the feed conditions such as feed length, number of feeds, feed rate, and acceleration during acceleration/deceleration from the operation panel 21 before starting press work, the SPM (unit time The number of times per feed) is instantaneously calculated by this arithmetic circuit 33a and displayed on the display device 23.
It is possible to judge at a glance to what degree the rotational speed of the press machine 27 should be set. Therefore, as in the past, the rotation speed of the press machine 27 can be determined from a large number of SPM curve diagrams (in the example, there are 45 types of SPM curve diagrams since there are 9 types of maximum feed speed and 5 types of acceleration during acceleration/deceleration). Compared to the case of reading, the reading time can be significantly shortened, and the reading error is also extremely small. Also, compared to the conventional case where the number of rotations of the press 27 is set based on the operator's experience or the number of rotations of the press 27 is set by relying on the alarm function of the press 27 or the roll feeder 28. As a result, the settings are accurate, even beginners can perform efficient press work, and the setting time can be shortened.

Furthermore, since the remaining time for pressing work can be displayed, it becomes easier to schedule the work to be started next.

〔Effect of the invention〕

As described above, in the roll feeder control device of the present invention, the controller section has a calculation section that calculates at least the maximum number of times the roll feeder is fed per unit time based on the feeding conditions input by the set value input means. The configuration has the following. Therefore, the maximum number of feeds per unit time of the roll feeder can be instantly calculated for each feed condition, and the calculated value is displayed on the display device. Based on this value, the optimum rotation of the press machine that meets the feed conditions can be calculated. Anyone can set the rotation speed of the press quickly and effectively without having to determine the rotation speed of the press from an SPM curve diagram or relying on the operator's experience, as was the case in the past.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention, and FIG. 2 is a block diagram showing its configuration.
Fig. 3 is a diagram showing the relationship between feed speed and feed time in an embodiment of the present invention, Fig. 4 is a schematic diagram showing a general press line, and Fig. 5 is an SPM curve diagram of a roll feeder. It is a figure showing an example. 20...control device, 21...operation panel, 22...
Controller section, 23...Display device, 24...Driver section, 25...High-power unit section, 33...
Arithmetic section.

Claims (1)

[Scope of Claims] 1. A material to be conveyed is held between a pair of upper and lower rolls, at least one of the rolls is connected to a control motor, the control motor is used as a drive source, and the pair of rollers is controlled by a control signal from a control device. In a roll feeder that rotates a roll at a predetermined angle and uses the frictional force thereof to intermittently supply a material to be conveyed to a machine tool such as a press machine, the control device includes a set value input means for setting feeding conditions; a control circuit that sends a control signal to the control motor based on a feed condition given via the set value input means; and a roll feeder that sends a control signal to the control motor at least per unit time based on the feed condition given via the set value input means. A control device for a roll feeder comprising: a calculation unit that calculates the maximum number of times of feeding; and a display unit that displays the calculation results of the calculation unit.