JPS6025219B2 - Molding machine mold clamping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold clamping device for a vertical casting machine, etc., and in particular, in a Naoji type using fluid pressure such as oil pressure, the mold opening/closing speed can be efficiently controlled and the mold closing time can be improved. In addition to shortening the mold and aiming for smooth mold opening and closing, a high-voltage mold circuit was added in addition to the mold opening and closing circuit.
The present invention relates to a molding device for a molding machine that performs mold clamping efficiently.

A toggle link mechanism is used to open and close the mold in a vertical casting machine, but this makes the mechanism complicated and large.

Mold opening/closing, especially mold closing, needs to be controlled slowly at the beginning of the mold closing process, quickly during the middle stage, and slowly at the peak stage just before the mold closes, and the control must be accurate. If this is not done, the movable mold and the fixed mold will collide and cause damage, so a toggle link mechanism is used as described above to control the speed. A direct pressure type using a hydraulic cylinder unit has been proposed in place of the above-mentioned toggle link type mold opening/closing device, but it is not as fast as the toggle link type, and when performing speed control, especially deceleration, conventionally a solenoid switching valve is used. Since the hydraulic circuit is switched and the amount of oil supplied to the cylinder is changed in stages, a shock occurs and there are problems such as unfavorable operation.

On the other hand, it has been proposed to apply high pressure to the above-mentioned direct-pressure type mold opening/closing cylinder unit to perform molding, but in addition to the above-mentioned problems with the mold opening/closing operation, the pump capacity would also be large and an extremely high pressure would be required. , there are plumbing and other problems.

Therefore, in addition to the mold opening/closing cylinder unit, a cylinder unit dedicated to mold clamping is also installed, but in the past, each unit had a separate pump and hydraulic circuit, which resulted in a large number of pumps, piping, and hydraulic pressure. The number of devices increases, leading to an increase in the number of parts, a complicated structure, troublesome manufacturing, complexity, and increased costs. The present invention has been made to improve such conventional disadvantages, and its purpose is to efficiently control mold opening and closing, shorten mold closing time, and plan smooth mold opening and closing. A high-pressure mold clamping circuit is attached to the circuit, and a direct pressure type mold opening/closing cylinder is used to efficiently open and close the mold vertically.
In conjunction with this, mold vertical hydraulic pressure is supplied to the mold opening/closing cylinder and a separate mold vertical cylinder from a high-pressure circuit common to the cylinder, thereby making mold clamping more efficient and designed to simplify the circuit. The type of machine is to provide vertical equipment.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is an explanatory diagram of the circuit of the device according to the present invention, Figs. 2 and 3 are a front view and side view of a main part of the casting machine;
The figure shows a cross-sectional plan view of the main part.

The casting machine 1 is as shown in FIGS. 2 and 3, and has a substrate 2.
Tie bar 3 erected on the four corners of...Fixing plate 4 at the top end
A movable plate 5 is slidably mounted with iron on the tie bar 3 between them, and a lower mold 6 is supported on the substrate 2, and an upper mold 7 is supported under the movable plate 5. .

A mold opening/closing cylinder unit 8 is installed on the center of the fixed plate 4, and the cylinder 8a has a piston 8b slidably formed inside thereof, and the piston rod 8c extends downward from the cylinder 8a. The distal end of the movable plate 5 is connected to the center of the movable plate 5 through a vertical hole 4a in the center of the fixed plate 4. Therefore, the movable plate 5 moves up and down as the piston 8b moves up and down as pressure oil is introduced into and discharged from the cylinder, thereby opening and closing the mold. Inside the tie bars 3 at the four corners, four mold vertical cylinder units 9 are provided on the fixed plate 4 side so as to surround the mold opening/closing cylinder unit 8 in the center, and the unit 9 includes a piston 9b in a cylinder 9a. , the piston rod 9c is suspended, and when the mold is opened as shown in FIG. As shown in Figure 3, when the mold is closed, the rotary plate 10 rotates, and the rod 9c is moved by the pressure receiving rotary plate 10.
It hits the top and applies mold clamping pressure to the movable plate 5 via this.
This is shown in Figure 4. To explain the present invention based on FIG. 1, the flow rate control directional switching valve 11 has a neutral cutoff position A shown in the figure, a mold closing position B offset to the right consisting of an X-shaped spool, and a parallel spool. The mold opening position C is offset to the left.

A line 12 at the upper end of the cylinder 8a above the piston 8b and a line 13 at the lower end of the cylinder 8a below the piston 8b are led in parallel to the cylinder side of the flow rate control directional switching valve 11, and the oil tank 14 side of the valve 11 is A pressure oil line 16 and a discharge line 17 connected to the pump 15 are led in parallel. The flow rate control direction selector valve 11 is controlled by a control device D as shown in FIGS. 1, 5 to 7.

A potentiometer 19 connects any part of the rod 8c that moves the movable plate 5 up and down, or any part of the movable plate 5 to a belt-shaped movable member 18, and acts as a position detector via this 18. Connect to. Therefore, as the rod 8c moves, the actual movement amount of the movable plate 5 via the movable member 18,
That is, the position is measured and output as a voltage value. The position detector 19 functions as a position detector for the rod 8c, that is, the piston 8b, with characteristics as shown in FIG. 20' is a potentiometer that acts as a position setting device, and this 20 is used to designate a shift position such that the moving speed of the piston 8b is changed to a predetermined speed at the moving position (elevating movement position) of the piston 8b. The position is output as a voltage value.

A plurality of position setting devices 20 are arranged as shown in FIG.
Each of the position setters 20-1 to 20-n specifies a multi-step speed change position of the piston 8b, and hence the movable plate 5 that supports the upper die. Reference numeral 21 denotes a voltage comparator, to which the output of the position detector 19 and the output of the position setting device 20 are respectively input, and the magnitudes thereof are compared.

As shown in FIG.
It is set up to correspond to the river. The outputs compared by the comparator 21 are inputted to the flow rate controller 22 via the amplifier 23, and this input operates an adjustable control element to set the piston 8b at a desired speed, so as to set the piston 8b at a predetermined speed. The flow rate control directional switching valve 11 is controlled. To further explain the configuration of the control device in detail with reference to FIG. 6, a plurality of position setters 20-1 to 20-n are prepared for one position detector 19,
Comparators 21-1 to 21 for each position setting device 2
1n and amplifiers 23, ie, 23-1 to 23-n.
The outputs of the amplifiers 23-1 to 23-n are connected to control elements 22-1 to 22-n provided within the flow rate controller 22.
Each of the control elements 22-1 to 22-M can adjust the piston 8b to a desired speed. The voltage output of the position detector 19 is input to all comparators 21-1 to 21-n, while each comparator 21-1 to 21-n can vary the output voltage as the corresponding sliding resistor. Position setting device 20-
Voltage values from 1 to 20-n are input.

The set voltages of the position setters 20-1 to 20-1n are set to increase as the auxiliary number n increases, taking into consideration the piston speed or the output characteristics of the position detector shown in FIG. Position detector 19 output according to the characteristics shown in Figure 7
When the output voltage of becomes higher than the set voltage, the corresponding comparator outputs an output, operates the corresponding control element via the next stage amplifier, and controls the piston 8b via the flow rate control directional control valve 11. This acts to force the speed to a preset speed. FIG. 5 shows an example of the relationship between the amount of movement of the piston, that is, the amount of descent for mold closing, and the speed. Hydraulic pressure acts on the upper surface of the piston 8b of the cylinder schnit 8, and the piston 8b begins to move down (see FIG. 5). In the initial stage, it moves at low speed for starting (state a in Fig. 5), and in the low speed state, the output voltage of the position detector 19 becomes larger than the set voltage of the position setting device 20-1, and the comparison device 21-1, amplifier 23-1,
This is done by controlling the flow rate control direction gate valve 11 via the control element 22-1 to reduce the speed of the piston 8b.

Next, when the piston 8b moves further down and exceeds the middle point in FIG. It is moved at high speed (state b in FIG. 5). The piston 8b further moves downward to a position close to the lower limit of movement (
When the voltage reaches point C in Fig. 5), the voltage becomes higher than the set voltage of the position detector, and the control element controls the piston 8 in the same way as above.
The speed of piston 8b is rapidly reduced to a low speed state (state c in FIG. 5), and then the piston 8b is stopped at point 2 in FIG.

Thus, the mold closing movement, that is, the downward movement of the piston 8b, is stopped.
This deceleration prevents the upper and lower molds from colliding, and allows the molds to align smoothly and without impact, closing the mold. By adjusting the position setters 20-1 to 20-n in this way, the control elements 22-1 to 22-n can be set at any position of the piston 8b.
By adjusting 22-n, the speed of the piston 8b can be selectively changed to an arbitrary speed.

Pump 15 on the tank 14 side of flow rate control directional control valve 1 1
Downstream of the pump 15 in the line 16 connected to the
A check valve 24 is provided on the side of the line 13 connecting the lower end of the cylinder 8a and the control valve 11, which is closer to the valve 11, to block the pressure on the lower surface of the piston 8b, and from the valve 11 side. A check valve 25 is provided to allow the pressure of .

The line 13 is branched off at an appropriate point on the cylinder 8a side of the check valve 25, and the line 27 is branched from the branch point 26.
is connected downstream of the check valve 24, that is, on the valve 11 side, of the line 16 having the previously described pump 15, thereby forming a bypass line. This line 27 has a Schilling piston 8b.
Pump 1 that allows the lower hydraulic pressure and passes through check valve 24
A check valve 28 is interposed to cut off the hydraulic pressure of 5. Reference numeral 29 is a pilot check valve that allows hydraulic pressure from the valve 11 interposed between the branch point 26 of the line 13 and the cylinder 8a, and is operated by a solenoid switching valve 30, and the valve 29 normally opens the line 13. , allowing the oil below the piston 8b to flow toward the check valve 25 side. In the above, FIG. 1 shows the mold opening state, and the flow rate control direction sliding valve 11 is moved to the left from the neutral position A shown, and the line 12,
13 and lines 16 and 17 are connected at position B.

Shoyu from pump 15 connects line 16 to check valve 2
4 from the valve 11 to the line 12 and introduced onto the piston 8b in the sill 8a, causing the piston 8b to move downward. The downward movement speed, that is, the mold closing speed, is smoothly controlled by operating the valve 11 by comparing the predetermined setting device 20 with the detector 19 that measures the moving position of the piston 8b as described above. . As the piston 8b moves downward, the oil on the lower surface of the piston 8b is discharged through the line 13, and since the oil is blocked by the check valve 25, it flows through the bypass line 27 and the check valve 28 to join the line 16. The oil that has joined the line 16 is prevented from flowing back to the pump 15 side by the check valve 24, and the oil that has joined the line 16 is prevented from flowing back to the pump 15 side.
6 and 12 onto the piston 8b, and is involved in mold closing. Therefore, the amount of oil supplied by the pump 15 is equal to that of the piston. The volume of the pad 8c is sufficient. In this way, the mold can be closed quickly and smoothly, and the above can be done while controlling the speed.
When opening the mold, the valve 11 is moved to the right from the neutral position A so that the line faces the position C.

As a result, the lines 16 and 13 are allowed to flow, and the hydraulic oil passes through the check valves 24 and 25 to the piston 8b of the cylinder 8a.
The oil flows downward and moves the piston 8b upward, and since the oil pressure is blocked by the check valve 28, the oil on the upper surface of the piston 8b is prevented from flowing into the bypass line 27, while the oil on the upper surface of the piston 8b flows into the tank 14 via lines 12 and 17. The amount of oil returned and supplied into the sill 8a to move the piston 8b upward is equal to the piston volume minus the rod volume. By the way, when the piston underneath is suddenly stopped or stopped midway during the mold closing process, the valve 11 has dust that may cause leakage due to accuracy, etc., so in order to obtain stopping accuracy, the valve 30 must be switched to a pilot check valve. Line 13 is cut off at 29.

As a result, the line 13 is cut off before the valve 11, the downward movement of the piston 8b is locked, and the piston 8b is accurately stopped at a predetermined position. A mold clamping circuit is added to the above circuit.

As shown in FIG. 1, a high pressure second pump 31 is connected in parallel with the pump 15.
, the pump 15 is the first pump, and the line 32 of the second pump 31 is led to a solenoid switching valve 33 , which opens in parallel with the line 32 to a discharge line 34 returning the liquid to the tank 14 .

Two lines 35 and 36 are arranged in parallel downstream of the valve 33, one line 35 being connected to the already mentioned line 12, and the other line 36 being connected to the already mentioned line 13. The switching valve 33 has a neutral position E, a mold clamping position F on the right, and a mold opening position G on the left. In the latter stage of mold closing by the flow rate control valve 11 of the previously described shilling unit 8, or after the mold is closed, the switching valve 33 is moved to the left from the neutral position shown in the figure E, and the high-pressure oil pumped by the pump 31 flows through the lines 32 and 35. It joins the line 12 through the line 12, is supplied to the upper surface of the piston 8b, and performs mold clamping.
Since hydraulic pressure is already acting on the vertical mold when the mold is closed, the amount of oil required for the vertical mold can be reduced by further pressurizing this oil.
To release the mold vertically, move the switching valve 33 to the right and set it to position G.
As a result, high pressure oil passes through lines 32 and 36 to the piston 8.
V is supplied to the upper surface of b, and the adjacent type is performed by high pressure, and then returned to the neutral position. In this way, in addition to the above, the high pressure line is merged into the same line, high pressure is applied to the upper and lower sides of the piston 8b via the switching valve 33, and mold clamping and mold release are performed, without the need for a separate circuit. It is possible to simplify the circuit configuration and reduce the number of parts while performing the vertical operation using the same cylinder unit.

FIG. 1 includes the second aspect of the present invention.

The line 12 that supplies pressure oil from the first and second hydraulic power sources to the upper surface of the piston 8b of the mold opening/closing cylinder 8a described above is branched off from the part 12a on the cylinder 8a side at the confluence with the line 35, and the liquid is separated. Connect the skin line 38 to the solenoid switching valve 39.

The cut-off valve 39 has a neutral position shown in the figure, a mold clamping position 1 on the left, and a release position J on the right.
A line 40 connected to the upper surface of the piston 9b and a line 41 connected to the lower surface of the piston 9b are provided downstream of the valve 39, and the line 41 is opened at the time of mold clamping by the pressure of the line 40, and the oil on the lower surface of the piston is drained to the valve 39.
A pilot check valve 42 that opens on the 9 side is interposed, and a discharge line 43 to the tank 14 is provided before the valve 39. In the above process, the mold is closed as described above while the valve 39 is held at the neutral position in the figure, and then the valve 39 is moved to the right to face position 1.

As a result, the second pump 31
The high-pressure oil is supplied to the upper surface of the piston 9b of the mold clamping cylinder 9a, and the piston 9b is pushed down to perform the mold clamping movement.
The check valve 42 in line 41 is opened by the pressure in line 40. It is necessary to release the mold clamping force when the mold is adjacent to the mold, but in this case, the valve 39 is moved to the left after reaching the neutral position, so that the oil in the second hydraulic source 31 is transferred to the line 12.
a, 38, flows into the line 41, passes through the check valve 42, is introduced to the lower surface of the piston 9b, and is introduced into the piston 9b.
moves to release the vertical mold, the oil on the upper surface of the piston 9b is discharged into the tank 14 through lines 40 and 43, and after release, the valve 39 is set to the neutral position. Subsequently, as described above, the valve 33 is switched to release the mold vertical position of the mold opening/closing cylinder 8a. In this way, the mold cylinder is released before the mold opening/closing cylinder.
Although the embodiments have been described above, the mold vertical cylinder unit 9 does not necessarily need to be provided on the fixed plate 4 side, and may be provided on the five movable plates.

As is clear from the above, according to the present invention, the mold can be opened and closed quickly and smoothly using a direct pressure system, and an efficient and mechanically simple mold opening/closing mechanism can be obtained. By simply connecting to the mold opening/closing circuit, molding can be performed efficiently and with a simple device.

In addition, since a mold clamping cylinder is installed separately and operated by connecting it to the above-mentioned high-pressure circuit via a switching valve, mold verticalization can be performed using the same hydraulic power source as the mold opening/closing cylinder, and the circuit, Not only can the device be simplified, but also efficient vertical molding can be performed.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and Fig. 1 is an explanatory circuit diagram of the device according to the present invention, Fig. 2 is a cutaway front view of the main part of the casting machine in the mold open state, and Fig. 3 is the same model. A similar side view in the closed state, FIG. 4 is a cross-sectional plan view of the same essential parts, FIG. 5 is a diagram showing an example of the relationship between piston movement amount and speed, and FIG. 6 is a circuit of an example of the control device. FIG. 7 is a diagram showing the output characteristics of the position detector. In the drawing, 1 is a molding machine, 8 is a mold opening/closing cylinder, 9 is a mold vertical cylinder, 2 is a base plate, 4 is a fixed plate, 5 is a movable plate, 15 is a first hydraulic power source, and 12, 13, 16, and 17 are molds. opening/closing circuit,
11 is a flow rate control direction control valve; 31 is a second hydraulic power source; 32;
34, 35, 36 are vertical operating circuits, 33 is a switching valve, 38
, 40, 41, and 43 are vertical cylinder operating circuits, and 39 is a switching valve. Traditional 1 box *2 Figure 3 Figure 5 Figure 7 *Musical 6 boxes

Claims (1)

[Scope of Claims] 1 a. A movable plate provided between the substrate and the fixed plate and moved while being guided by a tie bar; b. A movable plate that moves the movable plate to open and close the mold provided between the movable plate and the substrate. Mold opening/closing cylinder, c A line connecting each of the chambers partitioned by the piston of the mold opening/closing cylinder to the flow rate control directional switching valve, and a supply line connecting the flow rate control directional switching valve to the first hydraulic pressure source and the oil tank. and a discharge line, and a line that connects one chamber of the mold opening/closing cylinder, through which oil is discharged when the mold is closed, and the flow rate control directional switching valve, and is interposed in the line that connects the flow rate control directional switching valve to block the passage of oil to the flow rate control directional switching valve side. A bypass line that connects the check valve, a part of the line closer to the mold opening/closing cylinder than the check valve, and a supply line having the first hydraulic pressure source, and a bypass line that is interposed in the bypass line to supply oil to the supply line side. A mold opening/closing operation circuit consisting of a check valve that allows passage of the mold; A mold clamping operation circuit that performs mold clamping and mold clamping release by supplying and discharging high pressure oil from a hydraulic source;
A mold clamping device for a molding machine consisting of the above. 2 a. A movable plate that is provided between the substrate and the fixed plate and moves while being guided by a tie bar; b. A mold opening/closing cylinder that moves the movable plate to open and close the mold provided between the movable plate; c. a movable plate; A line connects the flow rate control directional switching valve to each of the chambers defined by the mold clamping cylinder and the piston of the d-type opening/closing cylinder provided between the tie bars on one side of the fixed plate, and the flow rate control directional switching valve and the first line. The flow rate control direction switching valve is interposed between the supply line and discharge line connecting the hydraulic power source and the oil tank, and the line connecting the flow rate control direction switching valve and one chamber of the mold opening/closing cylinder where oil is discharged when the mold is closed. A check valve that blocks passage of oil to the valve side, a bypass line that connects a portion of the line closer to the mold opening/closing cylinder than the check valve and a supply line having the first hydraulic power source, and a bypass line connected to the bypass line. established,
A mold opening/closing operation circuit consisting of a check valve that allows oil to pass through to the supply line side. a mold clamping operation circuit capable of supplying and discharging high pressure oil from a second hydraulic source to a mold opening/closing cylinder to perform mold clamping and mold clamping release;
f The mold clamping cylinder and the mold clamping operation circuit are connected through a switching valve, and high pressure oil from a second hydraulic pressure source is supplied to and discharged from the mold clamping cylinder by the switching valve to perform mold clamping and mold clamping release. A mold clamping device for a molding machine consisting of a mold clamping cylinder operating circuit and the above.