JP4869819B2 - Spacer block moving device in injection molding apparatus - Google Patents

Description

  The present invention relates to a moving device for a spacer block inserted between a piston and a movable platen of an injection molding device.

  Conventionally, as a mold clamping device for injection molding devices such as rubber and resin, (a) a fixed platen at the top, (b) a movable platen that can be moved up and down below, (c) movable with these fixed plates 2. Description of the Related Art A mold clamping device for an injection molding apparatus is known that includes a mold clamping cylinder that drives a movable plate in a state where a molding die is sandwiched between the plate and a mold, and performs mold clamping.

There are various types of mold clamping devices ranging from a small one of about 25 tons to a large one of about 2500 tons.
In this mold clamping device, it is necessary to secure a moving stroke of the movable platen of, for example, about 500 mm to 1 m for replacement of the molding die or other work. In the case of a small mold clamping device, The moving stroke of the piston (ram) can be kept as large as possible. Therefore, in the case of a small mold clamping device, the piston (ram) is directly applied to the movable platen and the clamping force of the clamping cylinder is increased. It is possible to act directly on the movable platen.

  On the other hand, in the case of a large mold clamping device, for example, in a large one such as a 2500-ton press, a stroke of about 25 mm can be secured as the stroke of the piston. Conventionally, as shown in FIG. 7, a spacer block 204 is inserted between the piston 200 and the movable platen 202, and the rising force of the piston 200, that is, the clamping force of the clamping cylinder 214 is applied to the spacer block 204. The information is transmitted to the movable platen 202 via 204.

  In the prior art, the spacer block 204 is configured by stacking a plurality of plates 204a, and the entire spacer block 204 is formed by adding or removing the plates 204a according to the thickness of the molding die 206. I was trying to adjust the height.

In the injection molding apparatus, it is necessary to lower the movable platen 202 greatly during setup change work such as change of the molding die 206.
In this case, if the spacer block 204 is on the piston 200 and in the lower space of the movable plate 202, the movable plate 202 cannot be lowered.

Therefore, it is necessary to move the spacer block 204 from the operating position on the piston 200 to a non-operating position that deviates horizontally from the lower space of the movable platen 202.
For this reason, in the conventional injection molding apparatus, the moving device 208 for the spacer block 204 is provided, and the moving block 208 moves the spacer block 204 to the operating position on the piston 200 indicated by a two-dot chain line in FIG. It is made to move between the non-acting positions indicated by.

Conventionally, as the moving device 208, a hydraulic cylinder 210 that moves the spacer block 204 along the guide rail 212 between an operating position and a non-operating position has been used.
However, in this case, the hydraulic cylinder 210 protrudes greatly in the lateral direction, which causes the injection molding apparatus to become large.
Further, when the spacer block 204 is positioned at the non-operating position, an offset load is applied to the piston 200, which causes a problem of oil leakage in the mold clamping cylinder 214.

  Furthermore, a connection structure between the spacer block 204 and the hydraulic cylinder 210 must be considered so that the spacer block 204 can be raised together with the piston 200 in a state where the spacer block 204 is located at the operation position on the piston 200. In addition, there is a problem that the structure of the moving device 208 is complicated, such that the guide rail 212 that also serves as a support must be moved up and down integrally with the piston 200.

The following Patent Document 1 discloses a structure in which the position of the link housing is moved by rotating the mold thickness adjusting nut with a mold thickness adjusting motor to cope with the change in the thickness of the molding die. ing.
However, the one disclosed in Patent Document 1 is different from the present invention in that the spacer block does not correspond to the change in the thickness of the molding die.

JP 2001-121594 A

  The present invention is based on the circumstances as described above, and the injection molding apparatus can be made compact, the structure is simple, and the spacer block can be easily moved between the non-operating position and the operating position. The object of the present invention is to provide a spacer block moving device in an injection molding apparatus that can smoothly lift and lower the block together with the piston without hindrance.

  Thus, according to the first aspect of the present invention, (a) an upper fixed platen, (b) a movable platen provided on the lower side thereof, and (c) a molding formed between these fixed platen and movable platen A mold clamping cylinder that clamps the movable plate by raising the movable plate in a state where the mold is sandwiched; and (d) a mold that is interposed between the piston of the mold clamping cylinder and the movable plate, and is formed by the mold clamping cylinder. A spacer block that exerts a clamping force on the movable plate; and a horizontal direction of the spacer block of the mold clamping device in the injection molding apparatus including the operation position on the piston and the space on the piston and the lower side of the movable plate. (A) a guide rail that moves and guides the spacer block between the operating position and the non-operating position, and (b) the spacer block. A moving mode is attached and drives the spacer block in the horizontal direction. And (c) a pinion gear provided on the spacer block so as to be rotatable about the upper and lower axes, and continuously provided along the movement direction of the spacer block, and the pinion gear. A rack gear that meshes with the pinion gear, and a moving mechanism that moves the spacer block as the pinion gear rotates, and the rack gear is located at the operating position on the piston. On the other hand, it is provided with a length that maintains the meshing state.

  According to a second aspect of the present invention, in the first aspect, the guide rail has a guide groove at an upper end and below the inward flange portion, and the guide protrusion of the spacer block can be moved into the guide groove. The guide rail is provided with a length that guides the spacer block to the operating position on the piston, and the guide protrusion of the spacer block located at the operating position. In the upper position of the piston, the flange is removed, and the guide protrusion can be detached upward from the guide groove. On the other hand, the piston has a piston side flange that covers the guide protrusion from above. The portion is provided so as to move up and down integrally with the piston.

Effects and effects of the invention

  As described above, the present invention provides a guide rail for moving and guiding the spacer block between the operating position and the non-operating position, a moving motor attached to the spacer block, and a pinion gear provided on the spacer block and rotated by the moving motor. And a rack gear meshing with the pinion gear, and a moving mechanism for moving the spacer block with the rotation of the pinion gear to form a spacer block moving device, and the rack gear is a spacer block located at the operating position on the piston. The pinion gear is provided with a length that maintains the meshing state.

  In the present invention, the spacer block is moved between the operating position and the non-operating position by the moving motor based on the meshing between the pinion gear and the rack gear. The injection molding apparatus can be configured more compactly than the conventional apparatus in which the spacer block is moved by a hydraulic cylinder.

  In the present invention, the pinion gear is provided so as to be rotatable about the upper and lower shaft centers, and the pinion gear is meshed with the rack gear. The spacer block can be moved up and down together with the piston while maintaining the engagement between the pinion gear and the rack gear, so that the spacer block located at the operating position can be moved up and down integrally with the piston. Therefore, there is no need to provide a complicated mechanism in the moving device, and this provides an advantage that the moving device can be configured with a simple structure.

  Next, a guide groove is provided in the guide rail so that the guide projection of the spacer block is movably fitted therein, and the guide rail guides the spacer block to the operating position on the piston. A configuration in which the upper end of the guide rail and the inward flange portion, that is, the flange portion that forms the guide groove on the lower side thereof is removed at the upper position of the guide projection of the spacer block that is provided in the length and is located at the working position. Thus, the guide protrusion can be detached upward from the guide groove, and in place of this, the piston side flange that covers the guide protrusion from above is moved up and down integrally with the piston. Provided.

According to the second aspect, when the spacer block is moved and guided from the non-operating position to the operating position, the spacer block can be moved and guided in the horizontal direction while being constrained up and down by the guide groove. By disengaging the guide protrusion of the spacer block and the guide groove of the guide rail, the spacer block can be lifted or lowered together with the piston alone.
In that case, since the piston side flange part which covers from the upper side with respect to the guide protrusion part of a spacer block is provided in the piston side, it can be raised / lowered in the state which restrained the spacer block to the up-down direction.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows the overall configuration of a rubber injection molding apparatus according to the present embodiment, in which 10 is an injection apparatus and 12 is a mold clamping apparatus.
The injection device 10 plasticizes the ribbon-like rubber material by the rotation of the screw of the extruder 14, fluidizes it, pushes it into the injection pot 16, and pushes the rubber material filled in the injection pot 16 downward of the plunger. Injection is performed from the injection pot 16 toward the molding die 32 described later by the forward movement.

The mold clamping device 12 has an upper holder 18 as an upper fixed platen and a mold clamping cylinder 20 constituting a lower fixed platen, which are connected to each other by a tie bar 22.
The mold clamping cylinder 20 is provided with a piston 26 that can be moved up and down in the cylinder chamber 24, and exerts a mold clamping force on the movable platen 28 via a spacer block 34 described later by raising the piston 26 by hydraulic pressure.

The movable platen 28 is provided on the lower side of the upper holder 18 so as to be movable up and down.
A lift cylinder 30 is connected to the movable plate 28. Here, the lifting cylinder 30 moves the movable plate 28 up and down with a large stroke.
The movable platen 28 is guided to move by the tie bar 22 during the lifting and lowering operation.

A molding die 32 is set between the upper holder 18 and the movable platen 28 and includes an upper die 32A, an intermediate die 32B, and a lower die 32C.
Reference numeral 34 denotes a spacer block interposed between the piston 26 and the movable plate 28. The spacer block 34 includes a male screw shaft 36, a nut 38 screwed onto the male screw shaft 36, and a support base 40 that supports the nut 38. And.

The structure of the spacer block 34 is specifically shown in FIGS.
As shown in FIGS. 2 and 3, the nut 38 has a cylindrical shape, and the male screw 44 of the male screw shaft 36 is screwed into the female screw 42 on the inner peripheral surface thereof.
The nut 38 is placed on the lower support base 40, and the entire lower surface (supported surface) of the nut 38 is rotatably supported by the upper surface (support surface) of the support base 40.

The upper surface of the support base 40 is provided with a lubricating oil reservoir 46 formed of a recess opening on the upper surface, and the lubricating oil retained therein is rotated over the entire upper surface of the support base 40 as the nut 38 rotates. In other words, the nut 38 is supplied to the rotational sliding surface with respect to the support base 40.
The support base 40 is provided with a supply path 48 that is bent in an L shape and communicates with the lubricating oil reservoir 46 and opens on the outer peripheral surface of the support base 40. The lubricating oil is replenished.
The support base 40 is provided with an insertion hole 50 into which the lower part of the male screw shaft 36 is inserted so as to be movable up and down.

In FIG. 3, reference numeral 52 denotes a rotary motor, which is attached to the support base 40 by a bracket 54.
A sprocket 55 is provided on the output shaft of the rotary motor 52, and a chain 58 is wound around the sprocket 55 and a sprocket 56 provided integrally with the nut 38. It is transmitted to the nut 38.

As shown in FIG. 2, guide bars 60 are erected on the upper surface of the support base 40 at a plurality of locations along the outer peripheral surface of the nut 38.
Guide rollers 62 are rotatably provided at the upper end portion and the lower end portion of the guide rods 60, and these guide rollers 62 are brought into contact with the outer peripheral surface of the nut 38 in a rotatable manner.

In this embodiment, the nut 38 is rotationally guided by the plurality of guide rods 60 and guide rollers 62 during the rotation operation, and the position perpendicular to the axis is regulated by them. That is, the guide bar 60 and the guide roller 62 hold the position perpendicular to the axis.
In this embodiment, the plurality of guide bars 60 and guide rollers 62 constitute a position holding means for the nut 38.

The nut 38 is also prevented from being lifted from the support base 40 by a hooking member 64 having a hooking claw at the upper end and the lower end, which is provided straddling the lower end of the nut 38 and the upper end of the support base 40.
The latch member 64 is provided with a proximity sensor 68 via a bracket 66.
On the other hand, a plurality of detected holes 70 are provided along the outer periphery of the nut 38 at a height position corresponding to the proximity sensor 68, and the nut 38 is detected by the detection of the detected hole 70 by the proximity sensor 68. The rotation amount is detected at every predetermined angle.
In the present embodiment, the proximity sensor 68 and the plurality of detected holes 70 constitute detection means for detecting the amount of elevation of the male screw shaft 36.

In the present embodiment, the height of the spacer block 34 is adjusted according to the mold thickness of the molding die 32 in FIG.
Specifically, this adjustment is performed as follows.
That is, when the nut 38 is rotated by the rotary motor 52 shown in FIG. 3, the male screw shaft 36 is moved up and down by the screw feed based on the screwing of the male screw 44 and the female screw 42.
Then, by adjusting the lifting amount, the overall height of the spacer block 34 is adjusted to an appropriate height according to the mold thickness of the molding die 32.

Then, in a state where the spacer block 34 is adjusted to the appropriate height shown in FIG. 4A, the mold clamping force of the mold clamping cylinder 20 is increased by raising the piston 26 as shown in FIG. 4B. The mold 32 can be clamped by the movable plate 28 and the upper holder 18 with a predetermined clamping force.
At this time, the piston 26 has a slight stroke due to the spacer block 34 being interposed between the movable platen 28 and the piston 26 and, further, the spacer block 34 is adjusted to an appropriate height. By raising (here, 25 mm stroke), the molding die 32 can be clamped with a required clamping force.

In the present embodiment, when the height of the spacer block 34 is adjusted, actually, this is automatically performed by the operator operating the setting switch.
That is, when the height adjustment amount of the spacer block 34 is set by the setting switch, the nut 38 is rotated by a rotation angle corresponding to the rotation motor 52 by a signal from the operation unit, and the male screw shaft 36 is moved to the nut 38. The screw is fed from the nut 38 by a distance corresponding to the amount of rotation, or retracted.
At this time, the elevation of the male screw shaft 36 is accurately controlled to a preset amount by the detection of the proximity sensor 68 with respect to the detection hole 70 of the nut 38.

In this embodiment, when it is necessary to largely lower the movable platen 28 during the setup change work such as changing the molding die 32, the spacer block 34 is shown in FIG. It is taken out from the piston 26 in the horizontal direction.
At this time, the lowering of the movable platen 28 with a large stroke or the subsequent raising operation is performed by the elevating cylinder 30 as shown in FIG.

As shown in FIG. 2, the spacer block 34 is moved and moved by the moving device 80 between an operating position on the piston 26 and a non-operating position deviating horizontally from the lower space of the movable platen 28. .
The moving device 80 has a pair of guide rails 82 provided on the mold clamping cylinder 20 along the moving direction of the spacer block 34.
The guide rail 82 has a U-shaped cross section, and has an inward flange portion 84 at the upper end thereof. A guide groove 86 is formed along the guide rail 82 below the guide rail 82.
In the guide groove 86, a guide roller 88 as a guide protrusion provided on the support base 40 in the spacer block 34 is fitted so as to be movable in the left-right direction in FIG.

Here, the guide roller 88 is provided on the side surface of the protruding portion 90 at the lower end of the support base 40 so as to be rotatable around a horizontal axis.
A guide roller 92 is also rotatably provided on the upper surface of the protrusion 90.
However, the guide roller 92 is in contact with the inner end face of the guide rail 82 and moves and guides the spacer block 34 along the guide rail 82 while restricting the position of the spacer block 34 in the direction perpendicular to the moving traveling direction. It is.

A movement motor (hydraulic motor) 94 is attached to the support base 40 of the spacer block 34 by a bracket 96 on its side surface.
A pinion gear 98 is provided on the output shaft of the moving motor 94 so as to be rotatable about the upper and lower axes, and the pinion gear 98 is meshed with a rack gear 100 provided along the guide rail 82.
The rack gear 100 is provided only along one guide rail 82.
The rack gear 100 is fixedly provided at a position above the guide rail 82 by a predetermined distance.

In the moving device 80, when the pinion gear 98 is rotated by the moving motor 94, the spacer block 34 is moved from the non-operating position to the piston 26 under the guide of the guide rail 82 based on the meshing between the pinion gear 98 and the rack gear 100. It can be moved to the upper working position.
Alternatively, it is moved from the operating position on the piston 26 to the non-operating position shown in FIG.

The rack gear 100 is provided in such a length as to keep meshing with the pinion gear 98 of the spacer block 34 located at the operating position on the piston 26.
The guide rail 82 is also provided with a length that guides the spacer block 34 to the operating position on the piston 26.
However, as shown in FIG. 6, the guide rail 82 has the upper end flange 84 removed at the upper position of the guide roller 88 of the spacer block 34 located at the operating position on the piston 26 (see (B)). The guide roller 88 can be separated upward from the guide groove 86 with respect to the flange portion 84.

On the other hand, on the piston 26 side, as shown in FIG. 2 and FIG. 6 (B), the piston side flange 102 instead of the piston 26 extends over the entire portion of the guide rail 82 where the flange 84 is removed. It is provided in a state where it moves up and down integrally.
Here, as shown in FIG. 4, the piston side flange portion 102 is provided inwardly at the upper end portion of the support rod 104 provided in a standing state on the piston 26.

In this embodiment, when the spacer block 34 in the non-operating position is brought to the operating position on the piston 26 by the rotation of the pinion gear 98 by the moving motor 94, the guide rail 82 and the guide roller 88 as shown in FIG. , 92 to guide the movement.
When the spacer block 34 reaches the operating position on the piston 26, the guide roller 88 of the support base 40 and the guide groove 86 of the guide rail 82 in the spacer block 34 are disengaged from each other. 88 is in a state of being detachable upward with respect to the guide rail 82.

On the other hand, at this time, the piston side flange 102 provided integrally with the piston 26 with respect to the guide roller 88 of the spacer block 34 located at the operating position on the piston 26 is as shown in FIG. The piston side flange 102 is in a state of restraining the guide roller 88 from the upper side.
When the piston 26 is raised in this state, as shown in FIG. 6 (C), the spacer block 34 remains in a state where the position of the guide roller 88 is restricted from the upper side by the piston side flange portion 102 together with the piston 26. Move up.
At this time, the spacer block 34 is raised together with the piston 26 while the pinion gear 98 and the rack gear 100 are kept engaged.

  On the other hand, when the piston 26 is lowered, the guide roller 88 of the spacer block 34 is positioned at the same height as the guide groove 86 of the guide rail 82, and in this state, the pinion gear 98 is rotated in the opposite direction. The spacer block 34 starts to move rightward in FIG. 2, and as the movement starts, the guide roller 88 is engaged with the guide groove 86 of the guide rail 82. Thereafter, the movement of the guide groove 86 is guided. The spacer block 34 is moved down to the non-operation position shown in FIG.

  In the present embodiment as described above, the spacer block 34 is moved between the operating position and the non-operating position by the moving motor 94 based on the meshing between the pinion gear 98 and the rack gear 100. The injection molding apparatus 10 can be configured more compactly than a conventional apparatus in which the cylinder is provided sideways and the spacer block 34 is moved by the hydraulic cylinder.

In the present embodiment, the pinion gear 98 is provided so as to be rotatable about the upper and lower shaft centers, and the pinion gear 98 is engaged with the rack gear 100, so that the spacer block 34 is positioned at the operating position on the piston 26. In this state, when the piston 26 is raised, the spacer block 34 can be moved up and down together with the piston 26 while maintaining the engagement between the pinion gear 98 and the rack gear 100.
Therefore, there is no need to provide a complicated mechanism in the moving device 80 in order to ensure the lifting and lowering movement of the spacer block 34 located at the working position integral with the piston 26, and thus the moving device 80 is configured with a simple structure. Can do.

Further, according to the present embodiment, when the spacer block 34 is moved and guided from the non-operating position to the operating position, the spacer block 34 can be moved and guided in the horizontal direction while being constrained up and down by the guide groove 86, and At the operating position, the guide roller 88 of the spacer block 34 and the guide groove 86 of the guide rail 82 are disengaged, and the spacer block 34 can be lifted or lowered together with the piston 26 alone.
At this time, since the piston side flange portion 102 is provided on the piston 26 side so as to cover the guide roller 88 of the spacer block 34 from above, the spacer block 34 can be moved up and down while being constrained up and down.

  Although the embodiment of the present invention has been described in detail above, this is merely an example, and the present invention can be configured in various forms without departing from the spirit of the present invention.

It is a figure which shows the whole structure of the injection molding apparatus containing the moving apparatus of one Embodiment of this invention. It is a perspective view which shows the spacer block and its moving apparatus of the embodiment. It is a figure which shows the spacer block of FIG. It is a figure which shows operation | movement of the piston at the time of clamping a shaping die. It is a figure which shows operation | movement of the raising / lowering cylinder in FIG. FIG. 3 is an explanatory view of an enlarged action of a main part of FIG. 2. It is a figure which shows an example of the conventional injection molding apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Injection molding apparatus 12 Clamping apparatus 18 Upper holder (fixed platen)
20 Clamping Cylinder 26 Piston 28 Movable Plate 32 Mold Die 34 Spacer Block 80 Moving Device 82 Guide Rail 84 Gutter 86 Guide Groove 88 Guide Roller (Guide Projection)
94 Movement motor 98 Pinion gear (movement mechanism)
100 rack gear (moving mechanism)
102 Piston side collar

Claims (2)

(B) an upper fixed platen, (b) a movable platen provided on the lower side of the movable platen, and (c) the movable platen with a molding die sandwiched between the fixed platen and the movable platen. A mold clamping cylinder that lifts the mold and clamps the mold, and (d) a spacer block that is interposed between the piston of the mold clamping cylinder and the movable plate and exerts a mold clamping force by the mold clamping cylinder on the movable plate. The spacer block of the mold clamping device in the injection molding apparatus comprising: between an operating position on the piston and a non-operating position that is horizontally deviated from the lower space on the piston and the movable platen. A moving device for moving,
(a) a guide rail for moving and guiding the spacer block between the operating position and the non-operating position;
(b) a moving motor attached to the spacer block and driving the spacer block in a horizontal direction;
(c) A pinion gear provided on the spacer block so as to be rotatable about an upper and lower axis, and continuously provided along the moving direction of the spacer block and meshed with the pinion gear. A rack mechanism that fits, and a moving mechanism that moves the spacer block as the pinion gear rotates.
And the rack gear is provided in such a length as to keep meshing with the pinion gear of the spacer block located at the operating position on the piston. Mobile device. 2. The guide rail according to claim 1, wherein the guide rail has a guide groove at an upper end and below the inward flange, and the guide protrusion of the spacer block is movably fitted into the guide groove. In addition, the guide rail is provided with a length that guides the spacer block to the operation position on the piston, and the flange portion is positioned above the guide protrusion of the spacer block located at the operation position. Is removed, and the guide projection can be detached upward from the guide groove,
On the other hand, a spacer block moving device in an injection molding apparatus, wherein the piston is provided with a piston side flange that covers the guide protrusion from above on the piston so as to move up and down integrally with the piston.

Images