JPH06307332A - Cylinder suction pressure feeding device - Google Patents

Abstract

PURPOSE:To provide a possibility of supplying always an appropriate amount of solution to the outside by furnishing a pulse output means to emit specified pulse signals in association with the movement of a piston, and furnishing a control means to slide or stop the piston in conformity to the counted value of the pulse signals. CONSTITUTION:A cylinder suction pressure feeding device is composed of a piston 6b to feed by pressure a sucked solution 2 to outside of a cylinder 5. a pulse output means 13, and control means 8, 14. When the piston 6b slides within the cylinder 5 in a certain direction, the solution 2 in a certain amount is sucked into the cylinder 5. With movement of this piston 6b, specified pulse signals are emitted from the pulse emitting means 13. The control means 8, 14 count these pulse signals, and if control on the basis of the counted value, the sliding direction of the piston 6b, for example in the counter-direction, the piston 6b slides within the cylinder 5 oppositely to the specified direction, and the sucked solution 2 is fed by pressure to the outside of the cylinder 5. The piston 6b may also be stopped appropriately on the basis of the counted value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder suction pressure feeding device suitable for use in supplying a release agent in, for example, a die casting method.

[0002]

2. Description of the Related Art FIG. 3 is a view showing the structure of a conventional cylinder suction pressure feeding device for supplying a release agent. Further, a die casting machine (not shown) is provided with a die for die casting. In the figure, reference numeral 1 is a container in which a release agent 2 to be sprayed on the mold is stored. Also, pipe 3
The end portion 3 a side of the is inserted into the release agent 2 in the container 1. On the other hand, the end portion 3b of the pipe 3 is attached to a predetermined position of the cylinder 5 and opens inside the cylinder 5.
A check valve 4 is inserted at a predetermined position of the pipe 3.

A cylinder 7 is provided so as to be in close contact with one end of the cylinder 5. Next, 6 is a piston rod, and the hole 5a provided in the cylinder 5 and the cylinder 7
And a hole 7a provided in the. Pistons 6a and 6b slidable in the respective cylinders are fixed to both ends of the piston rod 6, respectively.

Reference numeral 8 denotes an electromagnetic directional control valve, which sends pressure oil supplied from a hydraulic pump (not shown) to a path 16 or 17 in response to a control signal from the outside. Further, at a position facing the mounting position of the pipe 3 in the cylinder 5,
The end 9a of the pipe 9 is attached to the cylinder 5 as well.
It has an opening inside. A check valve 10 is inserted at a predetermined position of the pipe 9.

In the above structure, if pressure oil is sent to the path 16 under the control of the electromagnetic directional control valve 8,
In the figure, pressure oil flows into the cylinder 7 on the right side of the piston 6a. Therefore, the piston 6a moves leftward. At this time, since the piston 6b also moves to the left inside the cylinder 5, the volume on the right side of the piston 6b in the cylinder 5 increases. Then, an amount of the release agent 2 corresponding to this volume increase amount is sucked into the cylinder 5 via the pipe 3.

On the contrary, if pressure oil is sent to the path 17, the pressure oil flows into the left side of the piston 6a in the cylinder 7, and the piston 6a moves to the right. At this time, since the piston 6b also moves to the right in the cylinder 5, the volume on the right side of the piston 6b in the cylinder 5 decreases. At this time, the release agent 2 corresponding to this volume reduction amount
Is supplied to a sprayer (not shown) through the pipe 9.
Then, the release agent 2 is sprayed into a predetermined mold by the sprayer. In each case, the excess oil inside the cylinder 7 is returned to the oil tank (not shown) via the path on the side to which the pressure oil is not supplied.

[0007]

By the way, conventionally, the relationship between the moving time of the piston 6a in each direction and the supply amount of the release agent 2 is preliminarily assumed from experimental values and the like, and is electromagnetically controlled by a timer (not shown). The opening / closing state of the direction switching valve 8 and the timing for switching the direction have been controlled. However, when the temperature of the hydraulic oil in the cylinder 7 changes, its viscosity changes, and there is a problem that the actual operating stroke of the piston 6a differs from the assumed amount. Further, when the temperature of the pressure oil supplied to the electromagnetic directional control valve 8 changes, the amount of oil sent out also changes, causing the same problem. Also,
This could not be detected when the inner wall shape of the cylinder is not uniform and the piston does not slide smoothly, or when the piston malfunctions. In such a case, there has been a serious problem that the mold cannot be used without supplying an appropriate amount of the release agent. The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a cylinder suction pressure feeding device that can always supply an appropriate amount of solution to the outside.

[0008]

In order to solve the above-mentioned problems, in the invention according to claim 1, when sliding in the cylinder in a predetermined direction, a predetermined solution is sucked into the cylinder,
When sliding in the direction opposite to the predetermined direction, a piston that pumps the sucked solution out of the cylinder, a pulse output unit that outputs a predetermined pulse signal in accordance with the movement of the piston, and the pulse signal are counted to obtain a count value. And a control means for sliding or stopping the piston in any direction based on the above.

According to the second aspect of the invention, a predetermined solution is sucked into the cylinder when sliding in the cylinder in a predetermined direction, and the sucked solution is sucked when sliding in a direction opposite to the predetermined direction. A piston that is pressure-fed to the outside of the cylinder, a detection unit that detects when the piston reaches a predetermined position in the cylinder, and outputs a detection signal, and the piston is moved in either direction based on the detection signal. And a control means for sliding or stopping.

[0010]

According to the first aspect of the invention, when the piston slides in the cylinder in the predetermined direction, the predetermined solution is sucked into the cylinder. At this time, as the piston moves,
A predetermined pulse signal is output from the pulse output means. When the control means counts this pulse signal and controls the sliding direction of the piston in the opposite direction based on the count value, the piston slides in the cylinder in the direction opposite to the predetermined direction, and the sucked solution is transferred to the cylinder. It is pumped out. Also,
The piston can be stopped appropriately based on the count value.

According to the second aspect of the present invention, when the piston sliding in the cylinder reaches a predetermined position in the cylinder, the detecting means detects it and outputs a detection signal. Then, the control means similarly controls the sliding state of the piston based on the detection signal.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a cylinder suction pressure-feeding device according to the present invention. The parts common to the respective parts in FIG.

In the figure, reference numeral 12 is a rack gear, which is inserted into a hole 5b provided in the cylinder 5 and has one end fixed to a piston 6b. Reference numeral 13 is an encoder, which rotates by being meshed with the teeth of the rack gear 12 and outputs a pulse signal each time the rack gear 12 rotates by a predetermined angle. This pulse signal is an up-down pulse signal, and the moving direction of the rack gear 12 is also identified. Reference numeral 11 denotes a digital flow meter, which detects the flow rate of the release agent 2 flowing from the pipe 9 per predetermined time and digitally outputs the detected amount.

Reference numeral 14 is a control device, which receives and counts the pulses output from the encoder 13, and sends a control signal to the electromagnetic directional control valve 8 when a predetermined count is reached. Further, the total flow rate of the release agent 2 is calculated by detecting the flow rate output from the digital flow meter 11 and multiplying this by the elapsed time.

In the above structure, it is assumed that the piston 6b is initially stationary at the position shown in FIG. 4 (A). At this time,
The flow rate detected by the digital flow meter 11 is “0”.

Next, a control signal is sent from the control device 14 to the electromagnetic directional control valve 8, and pressure oil is sent to the path 16.
Then, the pistons 6a and 6b gradually move to the left.
At this time, the encoder 13 sequentially outputs the up pulse. The up pulse is sequentially counted by the control device 14. In addition, this count number is the same as in FIG.
It is assumed that it has been reset to "0" at the start of the operation in (A). Further, the amount of the release agent 2 corresponding to the volume increased as the piston 6b moves is sucked into the cylinder 5.

When the count value reaches a predetermined number, the control device 14 sends a directional switching signal to the electromagnetic directional switching valve 8. The predetermined count number is preset based on the volume of the cylinder 5. The position of the piston 6b at this time is shown in FIG.

Then, the pressure oil is sent out through the path 17, and the pistons 6a, 6b gradually move to the right. At this time, the down pulse is sequentially output from the encoder 13. Since this pulse is sequentially counted (minus count) by the controller 14, the count value gradually decreases from the above-mentioned predetermined number.

Further, with the movement of the piston 6b, the mold release agent 2 filled in the cylinder 5 is gradually supplied to a sprayer (not shown) through the digital flow meter 11, and the mold release agent 2 is applied to a predetermined mold. Will be done. In this process, the flow rate of the release agent 2 detected by the digital flow meter 11 is continuously digitally output.

The controller 14 detects this flow rate and multiplies it by the elapsed time to calculate the total flow rate of the release agent 2. Then, this total flow rate is constantly compared with a predetermined application amount set in advance.

When a sudden change is detected in the detected flow rate, an abnormal alarm is output as an abnormal situation. Further, even when the interval between the pulses supplied from the encoder 13 suddenly changes or the pulse becomes undetectable, an abnormality alarm is output similarly. Then, a "close" signal is supplied to the electromagnetic directional control valve 8 to interrupt the release agent supply operation. The cause of such an abnormal situation is mainly considered to be mechanical malfunction of the piston, the cylinder and the like. Therefore, it is possible to prevent an improper amount of the release agent from being applied to the mold by the operator inspecting these and correcting the defective portion.

Next, the piston 6b becomes the state shown in FIG. 4 (A) again. At this time, the pulse count number is "0" again.
Becomes At this time, if the above-mentioned total supply amount is less than the predetermined application amount, the control device 14 again sends a direction switching signal to the electromagnetic directional switching valve 8. As a result, the piston 6b moves to the left again, and the release agent 2 moves to the cylinder 5
Inhaled into.

In the state shown in FIG. 4B, the inhalation amount of the release agent is calculated from the pulse count value, the stroke amount per pulse, and the area of the top surface of the piston 6b. When the state (A) is reached, this may be compared with the total supply amount to calculate the error between the suction amount and the discharge amount. Even if this error amount is large, some kind of defect may be considered, and thus abnormality detection may be performed. Further, it is possible to omit the digital flow meter 11 by calculating the total supply amount from the inhalation amount calculated in this way.

Here, the piston 6b moves to the left as described above, and becomes the state shown in FIG. 4 (B) again. Then, the control device 14 again sends a direction switching signal to the electromagnetic directional switching valve 8, and the release agent 2 is supplied to the sprayer via the digital flow meter 11. The piston 6b is shown in FIG.
When the total supply amount reaches a predetermined coating amount in the state shown in (C), the controller 14 supplies a "close" signal to the electromagnetic directional control valve 8 to stop the release agent supply operation.

When it is necessary to apply the mold release agent 2 to another mold, the current pulse count value and the moving direction data of the piston 6b in the controller 14 are held, while the mold release agent 2 is held. The total supply amount data of 2 is reset. Then, when starting the operation of supplying the release agent to another mold, an appropriate control signal may be sent to the electromagnetic directional control valve 8. When the shape of the mold or the like changes and the coating amount is different, a predetermined coating amount may be newly set.

FIG. 2 shows the encoder 1 in FIG.
In this embodiment, a mechanical limit switch 15 is provided instead of No. 3. Switch dogs 12a and 12b are provided at predetermined positions of the rack gear 12. The limit switch 15 supplies a predetermined limit signal to the controller 14 when it contacts any of these switch dogs.

This limit signal is sent to the controller 14
When detected by the control device 14, the controller 14 sends a directional signal to the electromagnetic directional control valve 8. By repeating this, the reciprocating motion control of the piston as described above becomes possible. Further, a reflecting plate may be provided instead of each switch dog, and an optical limit switch may be used instead of the mechanical limit switch.

In the configuration shown in FIG. 2, the rack gear 1
Since the switch dog is provided on the switch 2, it is possible to selectively use the encoder or the limit switch depending on the case. When the limit switch is limited in use, a member to which a switch dog or a reflection plate can be fixed may be similarly provided instead of the rack gear.

As described above, according to these embodiments, the supply amount of the release agent is controlled based on the actual position information of the piston. Therefore, even when the temperature of the supplied pressure oil or the hydraulic oil in the cylinder changes, it is possible to always apply a predetermined amount of the release agent to the mold. In particular, since the mold is prevented from being damaged due to insufficient coating amount, the life of the mold is improved. Furthermore, since it is possible to detect mechanical malfunctions such as pistons or cylinders, fluctuations in the coating amount can be suppressed,
It is possible to improve the quality of castings.

Further, when such a cylinder suction pressure feeding device is always used for a mold having the same shape, a predetermined coating amount can be made to correspond to a constant piston reciprocating motion.
Therefore, by making the reciprocating stroke of the piston correspond to the coating amount, the same effect can be obtained without calculating the total supply amount.

[0031]

As described above, according to the present invention, since the position information of the piston in the cylinder is output by the pulse output means or the detection means, the actual amount of the solution sucked and pumped is controlled. It becomes possible. Therefore, it becomes possible to always supply an appropriate amount of solution to the outside.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a cylinder suction pressure feeding device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a cylinder suction pressure feeding device according to another embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional cylinder suction pressure feeding device.

FIG. 4 is a diagram showing changes in the position of the piston according to the operation of the embodiment of the present invention.

[Explanation of symbols]

 2 Release Agent (Solution) 5 Cylinder 6b Piston 8 Electromagnetic Directional Switching Valve (Control Means) 13 Encoder (Pulse Output Means) 14 Control Device (Control Means) 15 Limit Switch (Detection Means)

Claims (2)

[Claims] 1. A piston for sucking a predetermined solution into the cylinder when sliding in the cylinder in a predetermined direction, and pumping the sucked solution outside the cylinder when sliding in a direction opposite to the predetermined direction; A pulse output unit that outputs a predetermined pulse signal in accordance with the movement; and a control unit that counts the pulse signal and slides or stops the piston in either direction based on the count value. Characteristic cylinder suction pumping device. 2. A piston for sucking a predetermined solution into the cylinder when sliding in the cylinder in a predetermined direction, and for pumping the sucked solution out of the cylinder when sliding in a direction opposite to the predetermined direction; When reaching a predetermined position in the cylinder, a detection unit that detects this and outputs a detection signal, and a control unit that slides or stops the piston in either direction based on the detection signal are provided. A cylinder suction pressure-feeding device comprising: