JPH0229425B2 - DAIKASUTONIOKERUSAIKOSHASHUTSUSOKUDOKEISOKUSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for automatically measuring the maximum injection speed when pouring metal into a mold in a die-casting machine.

[Conventional technology]

Generally, the maximum injection speed in the injection process is measured for the purpose of controlling die casting conditions. That is, the quality of die-cast products usually has characteristics that other products do not have in terms of the fineness and smoothness of the casting surface. This is because the molten metal is squeezed when it passes through the gate when filling the mold cavity, so the speed of the molten metal is generally about 60 m/min.
The injection speed, which corresponds to sec and determines the condition of the casting surface, directly affects the speed of this gate section. However, the speed of this gate section is approximately 20 times faster than the plunger speed.
The injection speed that determines the condition of the casting surface is
Since the injection speed is magnified 20 times and changes, it is important to control the maximum injection speed in order to always stabilize the quality of die-cast products.

Therefore, conventional maximum injection speed measuring devices of this type are configured to hold the peak of the analog waveform related to the injection speed and measure this peak hold value, and those that are configured to measure the peak hold value, and those that are configured to hold the peak of the analog waveform related to the injection speed and measure the peak hold value. In addition to the configuration that automatically measures the average speed in this setting section, the injection speed waveform is
A known configuration is such that the speed is divided into sections (mm), the average speed of each section is determined, and the highest value is automatically measured.

[Problem to be Solved by the Invention] However, in the method of automatically measuring the peak hold value, as shown in FIG. 1, for example, in order to hold the peak of the analog waveform of the injection speed, the peak Vp of the surge component is There is a possibility of holding, and there is a drawback that a value higher than the practical maximum speed Vmax is measured.

Furthermore, in the method of automatically measuring the average speed in a set section, it is necessary to set in advance a measurement section in which the maximum speed will be achieved, as shown in FIG. 2, for example. However, due to changes in the injection speed characteristics (indicated by the broken line), the desired measurement section shifts, resulting in a drawback that the measured value of the maximum speed changes significantly.

Furthermore, in a method in which the injection speed waveform is divided into n (mm) units, the average speed of each section is determined, and the maximum value is automatically measured, the desired maximum injection speed can be obtained, for example, as shown in Figure 3. . However, as shown in Figure 4 a and b, the waveform at the highest injection speed is the same when it is sharp (see Figure 4 a) and when it is round (see Figure 4 b). The problem is that even at the highest speed, the measured values change significantly.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to detect the moving state of an injection mechanism with a pulse sensor, and to collect pulse period data detected at a predetermined timing from a pulse signal output from the pulse sensor from the start of injection to the end of injection. To provide a maximum injection speed measuring device for die casting capable of achieving proper maximum injection speed measurement with a simple configuration by storing and calculating and collating all stored pulse cycle data at the end of injection.

[Means to solve the problem]

The maximum injection speed measuring device for die casting according to the present invention includes a pulse sensor that detects a moving state of an injection mechanism, a pulse period detection circuit that detects a pulse period at a predetermined timing from a pulse signal of the pulse sensor, and a pulse period detection circuit. A memory circuit that chronologically stores the pulse cycle data from the start of injection to the end of injection obtained in Consisting of an arithmetic circuit that performs comparison calculations and stores them in memory and calculates the maximum injection speed from the calculation results finally stored in the memory, and a display circuit that displays the maximum injection speed calculated by the arithmetic circuit. It is characterized by

In the maximum injection speed measuring device described above, the pulse period detection circuit includes an internal clock generator,
It can be configured to detect the entire pulse period of the pulse signal supplied from the pulse sensor in accordance with the timing of the clock.

[Effect]

According to the maximum injection speed measuring device for die casting according to the present invention, the movement state of the injection mechanism is detected by a pulse sensor, a pulse period is detected at a predetermined timing from a pulse signal obtained by this pulse sensor, and the pulse period data is is stored chronologically in a memory circuit from the start of injection to the end of injection, and at the end of injection, the minimum total value of the pulse period is calculated from the data stored in the memory circuit, and the maximum injection speed is calculated based on this calculation result. It can be calculated appropriately and easily.

〔Example〕

Next, embodiments of the maximum injection speed measuring device according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 5 is a block circuit diagram showing an embodiment of the maximum injection speed measuring device of the present invention. That is,
In FIG. 5, the measuring device of the present invention includes a pulse sensor 10 that detects the injection speed of the injection mechanism, and a pulse period detection circuit that detects the pulse period of the pulse signal detected by the pulse sensor 10 using an internally generated clock. 12 and this pulse period detection circuit 1
2, a calculation circuit 16 for calculating the maximum injection speed from the data stored in the pulse period storage circuit 14, and a maximum injection speed calculated by the calculation circuit 16. It is composed of a display circuit 18 that displays speed.

Note that the pulse sensor 10 used in this embodiment includes, for example, a magnetoresistive element, a permanent magnet, a DC amplifier, and a voltage regulator incorporated therein.
Magnetic flux response method (resistance value changes according to magnetic flux)
As shown in Fig. 6, the magnetic flux is arranged close to rectangular grooves carved at minute intervals in the axial direction on the outer surface of the injection plunger of the injection mechanism, and the magnetic flux changes in accordance with the rectangular grooves. A commercially available product configured to output a pulse of constant amplitude every time can be used.

Therefore, in the present invention, the maximum injection speed is measured by the following procedure using a measuring device having the circuit configuration described above.

First, the pulse sensor 10 provided in the injection mechanism of the die-casting machine generates a required pulse output in conjunction with the injection operation (see FIG. 6). The pulse output of this pulse sensor 10 is set so as to generate one pulse every time the injection mechanism moves by n (mm), as shown in FIG. Next, the pulse signal thus obtained by the pulse sensor 10 is supplied to a pulse period detection circuit 12. The pulse period detection circuit 12 includes an internal clock generator 20,
The pulse period of the pulse signal generated per unit time is digitally detected by the clock generated by the clock generator 20. In this way, the pulse period data detected in time series by the pulse period detection circuit 12 is sequentially stored in the pulse period storage circuit 14. On the other hand, the arithmetic circuit 16
has a function of controlling the pulse period detection circuit 12, pulse period storage circuit 14, and display circuit 18, respectively, and uses external signals (injection start and injection end) as appropriate to generate control signals for controlling these in a timely manner. detection signal) is supplied.

However, when the calculation circuit 16 determines the injection start state based on the input of the external signal, it controls the pulse period storage circuit 14 to sequentially store the pulse period data detected in time series by the pulse period detection circuit 12. conduct. After that, when the arithmetic circuit 16 determines the injection completion state by inputting an external signal,
The maximum injection speed is calculated from the pulse period data stored in the pulse period storage circuit 14 by the following calculation process. For convenience of explanation, the memory format of all pulse period data stored in time series in the pulse period storage circuit 14 is shown in FIG.

First, a total pulse period value of m pieces of pulse period data from the start is calculated, and the calculation result is stored in the memory 22 provided in the calculation circuit 16, for example.

Next, a total pulse period value of m pieces of pulse period data from the second pulse period data from the start is calculated, and this calculation result and the memory 2
Compare with the contents stored in 2 (in this case,
The smaller the total value is, the faster the speed is).
If the current calculation result is small, the current calculation result is stored in the memory 22 and its contents are updated. Note that if the current calculation result is large, the contents of the memory 22 do not change.

The same arithmetic processing as in the above section is performed for all data areas obtained at the time of injection.

Therefore, the data finally stored in memory 22 will be the minimum sum of n pulse periods. Therefore, from this data, the maximum injection speed can be automatically measured by calculation using the following equation.

V (m/s) = n x m/total period, where n: mm/pulse (pulse period) m: number of pulses In this way, the maximum injection speed calculated by the arithmetic circuit 16 is immediately displayed on the display circuit 18. can be displayed.

〔Effect of the invention〕

As is clear from the embodiments described above, the maximum injection speed measuring device of the present invention extracts the operation of the injection mechanism during the injection process from the injection start point to the injection end point as a pulse signal, and generates a pulse based on this pulse signal. Period data is stored in chronological order, and at the end of injection, the minimum total value of the pulse period of a predetermined number of pulses is calculated from all the stored pulse period data, and the maximum injection speed is automatically calculated from this calculation result. It can be measured.

Therefore, according to the maximum injection speed measuring device of the present invention, the maximum injection speed can always be detected properly and reliably, and highly accurate automatic measurement of the maximum injection speed can be achieved. In addition, the measuring device of the present invention can be easily configured using a microcomputer, etc. equipped with a memory function, arithmetic function, and control function, and prevents erroneous measurements due to changes in injection speed characteristics as in the past. Therefore, it is possible to improve the performance and reliability of this type of measuring device.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.
Of course, various design changes can be made without departing from the spirit of the invention.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of a measurement procedure of a conventional maximum injection speed measuring device, FIG. 2 is an explanatory diagram showing another measurement procedure of a conventional maximum injection speed measuring device, and FIG.
The figure is an explanatory diagram showing yet another measurement procedure of the conventional maximum injection speed measuring device. Figure 5 is a block circuit diagram showing an embodiment of the maximum injection speed measuring device according to the present invention;
6 is a configuration diagram of the pulse sensor shown in FIG. 5, FIG. 7 is a waveform diagram of a pulse signal generated by the pulse sensor shown in FIG. 6, and FIG. 8 is a diagram of the maximum injection speed measuring device according to the present invention. FIG. 3 is a memory format diagram of data stored in a pulse period storage circuit showing a measurement procedure. 10...Pulse sensor, 12...Pulse cycle detection circuit, 14...Pulse cycle storage circuit, 16...
Arithmetic circuit, 18...Display circuit, 20...Clock generator, 22...Memory.

Claims (1)

[Claims] 1. A pulse sensor that detects the moving state of the injection mechanism, a pulse cycle detection circuit that detects the pulse cycle at a predetermined timing from the pulse signal of the pulse sensor, and the injection start time obtained by the pulse cycle detection circuit. A memory circuit that stores pulse cycle data in chronological order from the time to the end of injection, and a memory circuit that sequentially compares and calculates the minimum total value of pulse cycles for each predetermined number of pulses from all the pulse cycle data stored in the memory circuit. In a die-casting device, the method is comprised of an arithmetic circuit that calculates the maximum injection speed from the calculation results finally stored in the memory, and a display circuit that displays the maximum injection speed calculated by the arithmetic circuit. Maximum injection speed measuring device. 2. In the maximum injection speed measuring device according to claim 1, the pulse period detection circuit includes an internal clock generator and detects the total pulse period of the pulse signal supplied from the pulse sensor in accordance with the timing of the clock. Maximum injection speed measuring device in die casting consisting of detection.