JPH0136580Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a vertical injection molding machine in which the clamping direction of a pair of molds is vertical. This invention relates to a vertical injection molding machine equipped with a prefill valve.

[Background technology and its problems]

A hydraulic system is used as a drive source for an injection molding machine because it can generate high pressure, and various hydraulic devices and piping are installed in the injection molding machine. One of these hydraulic devices is a prefill valve, which opens when the movable mold of a pair of molds is rapidly advanced by the ram of the mold clamping cylinder, and supplies oil from the oil tank to the mold clamping cylinder. Immediately after the pair of molds are clamped, they close and supply high-pressure oil to the clamping cylinder.

In this way, the pre-fill valve is installed between the mold-clamping cylinder and the oil tank in the hydraulic circuit to supply oil from the oil tank to the mold-clamping cylinder. In this case, the injection molding machine becomes larger, and the longer the distance between the prefill valve and the oil tank, the longer the piping becomes, which goes against the desire to make the injection molding machine more compact.

[Purpose of invention]

The purpose of this invention is to create a prefill valve by utilizing the structural features of the vertical injection molding machine when the injection molding machine is a vertical injection molding machine in which the clamping direction of a pair of molds is the vertical direction. It is an object of the present invention to provide a vertical injection molding machine that can be effectively arranged to realize space saving, shortening of piping length, and compactness of the entire injection molding machine.

[Means and actions for solving problems]

For this reason, the configuration of the present invention is that in a vertical injection molding machine in which the clamping direction of a pair of molds by a clamping cylinder is the vertical direction, an oil tank is provided on the side of the clamping cylinder, and an orthogonal assembly is mounted on the clamping cylinder. It is characterized by the fact that a pre-filled valve is placed between the mold clamping cylinder and the oil tank.

Specifically, in the present invention, a first chamber and a second chamber are arranged side by side in the lower part of a box-like frame with an L-shape on the side, and a third and fourth chamber are arranged in the upper part above the second chamber. An injection device with the injection part facing upward is arranged in the first and second chambers, which are connected to each other, and the third chamber on the side of the first chamber in the upper stage is used as an oil tank, and the fourth chamber is used to drive a hydraulic pump. A motor is disposed, and a mold clamping device is disposed above the first chamber in which a pair of molds is clamped in a vertical direction by a mold clamping cylinder facing downward, and a prefill valve is orthogonally assembled to the mold clamping cylinder. The prefill valve is arranged between the mold clamping cylinder and the oil tank.

〔Example〕

FIG. 1 is a side sectional view of an injection molding machine according to this embodiment. In this injection molding machine, the injection part 2 of the injection device 1 faces upward, and the mold clamping device 3 has a vertical mold clamping direction in the vertical direction.

The frame 4 in which the injection device 1 etc. are arranged is formed into a large box shape, and the lower part has a first chamber 5 and a second chamber 6.
However, a third chamber 7 and a fourth chamber 8 are provided in the upper stage. Chambers 7 and 8 separated by partition wall 9 are chamber 6
The ceiling wall 10 of the chamber 6 is higher than the ceiling wall 11 of the chamber 5. For this reason, the frame 4 has an L-shaped side surface with a low-height chamber 5 provided on the side of the chambers 6, 7, and 8.

Since a through hole is formed in the partition wall 12 that partitions the chambers 5 and 6, these chambers 5 and 6 communicate with each other, and the chambers 5 and 6 serve as an arrangement space for the injection device 1. The chamber 7 is an oil tank filled with oil, and the hydraulic pump 13 is housed in the chamber 7. In the chamber 8, a motor 14 for driving a hydraulic pump 13 is mounted on a bracket 1 provided on the inner wall surface of the chamber 8.
The hydraulic pump 13 and the motor 14 are installed in the through hole 9 formed in the partition wall 9.
They are connected via A. These hydraulic pump 13 and motor 14 constitute a hydraulic unit, and oil from the hydraulic pump 13 is supplied to predetermined hydraulic equipment via a switching valve 16 installed in the chamber 8.

A mold clamping device 3 is disposed above the chamber 5 of the frame 4. The mold clamping device 3 includes a downward mold clamping cylinder 17 and a base member 1 that holds the mold clamping cylinder 17.
8, a movable platen 19 connected to the ram 17A of the mold clamping cylinder 17, a fixed platen 20, a tie bar 21 connecting the base member 18 and the fixed platen 20, and between the base member 18 and the fixed platen 20. An intermediate member 23 is interposed and receives a tightening force from a nut 22 screwed onto the tie bar 21. An upper mold 26 is attached to the lower surface of the movable platen 19, and a lower mold 27 is attached to the upper surface of the fixed platen 20.
27 is vertically clamped by the mold clamping cylinder 17.

The above-mentioned mold clamping device 3 is generally formed into a substantially rectangular prism shape, and has a shape and size that are compatible with the arrangement space left in the upper part of the chamber 5. Therefore, when the mold clamping device 3 is installed on the ceiling wall 11 of the chamber 5, the mold clamping device 3 fills the empty space of the frame 4, which is L-shaped on the side, and the injection molding machine is constructed as shown in FIGS.
As shown in Figures 3 and 3, it has a compact configuration that makes effective use of space.

The injection device 1 includes a hydraulic motor 28, a hopper 29 for material input, and a drive unit 31 for transmitting the driving force of the hydraulic motor 28 to a screw for a material kneading and plasticizing device housed inside a cylinder 30. The injection cylinder 32, which is composed of an injection cylinder 32 provided at the tip of the cylinder 30 and a nozzle 33, and in which an injection plunger is housed and constitutes the injection section 2, is mounted upward at right angles to the horizontal cylinder 30. . Hopper 29,
The cylinder 30 etc. are connected to the drive unit 3 by a connecting member 34.
1, and this drive unit 31 is attached to a truck 35 with a shaft 36 so as to be able to swing vertically, so that the injection device 1 can swing vertically. A rail member 37 is laid in the chambers 5 and 6, and the cart 35 can run on this rail member 37.

As shown in FIG. 2, cylinders 38 are provided on both left and right sides of the injection section 2 of the injection device 1, and the lower end of this cylinder 38 is connected to the bracket 3 provided on the injection section 2.
9 , the injection section 2 is in a suspended support state, and the downward weight of the injection device 1 centered on the shaft 36 is supported by the cylinder 38 . As the cylinder 38 contracts, the injection device 1 swings upward about the shaft 36, and the first
As shown in the figure, the nozzle 33 penetrates the hole 11A of the ceiling wall 11 and the hole 20A of the fixed platen 20 and comes into pressure contact with the lower mold 27, and the mold is clamped by the operation of the mold clamping cylinder 17. Upper mold 2
6. The mold is configured to inject molten material into the cavity of the lower mold 27.

When the cylinder 38 is extended, the injection section 2 descends and the injection device 1 swings downward about the shaft 36. Further, since the cart 35 is manually moved along the rail member 37, the periphery of the nozzle 33 is exposed, and work such as inspection and repair of the nozzle 33 etc. can be performed.

Note that the upper end of the cylinder 38 is connected to the ceiling wall 11.
Since the nozzle 33 is connected to the fixed platen 20 through the cylinder 38, when the injection part 2 is raised by the contraction movement of the cylinder 38, the nozzle 33 comes into precise pressure contact with the position of the sprue bush of the lower die 27. ing.

In the above, as is clear from FIG. 1, the oil tank formed by the chamber 7 is provided on the side of the mold clamping cylinder 17. Further, a prefill valve 24 is assembled to the upper part of the mold clamping cylinder 17, and this assembly is performed perpendicularly to the mold clamping cylinder 17.
It is located between 7. These oil tanks and the prefill valve 24 are connected by an oil pipe 25,
As shown in FIG. 3, two oil pipes 25 are provided which are bent into an L-shape in plan.

FIG. 4 shows the internal structure of the prefill valve 24 and the mold clamping cylinder 17. A ram 17A is housed inside the clamping cylinder 17 so as to be vertically slidable, and a booster ram 40 whose upper end is fixed to the clamping cylinder 17 is inserted inside the ram 17A. The movable platen 19 is connected to the lower end of the ram 17A, and the ram 17A is provided with a cylinder 41 and a piston 41A for ejecting the molded product.

Furthermore, the pre-fill valve 24 is mounted on the upper part of the mold clamping cylinder 17 orthogonally to the mold clamping cylinder 17 as described above. An oil chamber 42 connected to the oil tank via the oil pipe 25 is formed inside the pre-fill valve 24, and this oil chamber 42 communicates with the inner chamber of the mold clamping cylinder 17 via an oil passage 43. ing.

Further, a valve member 44 that can move forward and backward is provided inside the pre-fill valve 24, and this valve member 44 is always urged in the forward direction by a spring 45. Valve member 4
The inner chamber 44A of the booster ram 40 is connected to the hydraulic pump 13 via an oil passage 46, and the inner chamber 40A of the booster ram 40 is also connected to the hydraulic pump 13 via an oil passage 47.

When the movable platen 19 is lowered from the state shown in FIG. 4 by the operation of the ram 17A of the mold clamping cylinder 17, high pressure oil is supplied from the hydraulic pump 13 to the inner chamber 40A of the booster ram 40. At this time, the valve member 44 is retracted against the spring 45 due to the hydraulic pressure supplied from the port portion 48, so the oil chamber 42 and the oil passage 43 communicate with each other, and the pre-filled valve 2
4 is in an open state, and therefore a large amount of oil flows from the oil tank into the inner chamber of the mold clamping cylinder 17, while the ram 17A and the movable platen 19 are injected into the high pressure oil supplied to the inner chamber 40A of the booster ram 40. Then, it rapidly descends and clamps the upper mold 26 and the lower mold 27 together.

When the upper mold 26 and the lower mold 27 are clamped, a switch (not shown) that detects this stops the supply of hydraulic pressure to the port portion 48, and thereby the valve member 44
The spring 45 moves forward under the biasing force of the spring 45 and comes into contact with the valve seat portion 49 . As a result, communication between the oil chamber 42 and the oil chamber 43 is cut off, and the prefill valve 24 is in a closed state. Thereafter, high pressure oil is supplied from the oil pump 13 to the inner chamber 44A of the valve member 44, and this high pressure oil flows into the inner chamber of the mold clamping cylinder 17 through the oil passage 43.
Therefore, the ram 1 together with high pressure oil from the oil pump 13 flowing into the inner chamber 40A of the booster ram 40
7A, a large pressing force is applied to the movable platen 19, and the upper mold 26 and lower mold 27 are clamped with a large mold clamping force.

When raising the ram 17A and the movable platen 19 after injection molding, hydraulic pressure is supplied to the port section 48 to move the valve member 44 backward, and at the same time hydraulic pressure is supplied to the port section 50 of the mold clamping cylinder 17 to raise the ram 17A. As the ram 17A rises, the oil stored in the inner chamber of the mold clamping cylinder 17 flows into the oil passage 43, as the ram 17A rises.
It returns to the oil tank via the oil chamber 42 and the oil pipe 25.

When the ram 17A, movable platen 19, and upper die 26 are rapidly lowered, the oil in the oil tank is drained from the prefill valve 2.
As described above, since there are two oil pipes 25 that flow into the oil chamber 42 of No. 4 and the inner chamber of the mold clamping cylinder 17, the amount of oil supplied to the mold clamping cylinder 17 can be increased. In addition, as mentioned above, the prefill valve 24 is placed between the oil tank and the mold clamping cylinder 17, and since this placement location is a dead space where no other parts are placed, the prefill valve 24 is placed in a space-saving manner. This can be done through effective utilization, and the injection molding machine as a whole can have a compact configuration. Furthermore, since the prefill valve 24 is adjacent to the oil tank provided on the side of the mold clamping cylinder 17, the length of the oil pipe 25 connecting the oil tank and the prefill valve 24 can be shortened, and the overall length can be reduced. As a result, the hydraulic circuit can be simplified.

[Effect of idea]

According to the present invention, since the prefill valve is placed by effectively utilizing dead space, it is possible to save space and make the entire injection molding machine more compact, and the prefill valve is placed between the mold clamping cylinder and the oil tank. This makes it possible to shorten the length of piping from the oil tank to the prefill valve.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of the injection molding machine, FIG. 2 is a front view thereof, FIG. 3 is a plan view thereof, and FIG. 4 is a sectional view showing the internal structure of a prefill valve and a mold clamping cylinder. 1... Injection device, 3... Mold clamping device, 4... Frame, 5... First chamber, 6... Second chamber, 7... Third chamber which is an oil tank, 8... Fourth chamber, 13... Hydraulic pump, 17... Mold clamping cylinder, 19... Movable platen, 20... Fixed platen, 24... Prefill valve, 26... Upper mold, 27... Lower mold.

Claims (1)

[Scope of utility model registration request] A first chamber and a second chamber are arranged side by side in the lower part of a box-like frame with an L-shaped side surface, and a third and fourth chamber are arranged in parallel above the second room in the upper part, and the first and fourth chambers are in communication with each other. The injection device with the injection part facing upward is placed in the second chamber, the third chamber on the side of the first chamber in the upper stage is used as an oil tank, and the motor for driving the hydraulic pump is placed in the fourth chamber. A mold clamping device is arranged in which the mold clamping cylinder faces downward and the mold clamping direction of the pair of molds is in the vertical direction, and a prefill valve is orthogonally assembled to the mold clamping cylinder, and the prefill valve is used as the mold clamping cylinder. A vertical injection molding machine, characterized in that it is disposed between the oil tank and the oil tank.