JP3087317B2 - Screw-type resin injection equipment for injection molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw-type resin injection device for injection molding, and more particularly to a screw-type resin injection device used for an injection molding device for a multi-liquid reaction-curable resin.

[0002]

2. Description of the Related Art An injection molding apparatus has a screw-type resin injection apparatus for injecting and filling a resin (resin material) into a cavity of a molding die. The screw-type resin injection apparatus is generally an in-line screw type. There is an injection cylinder member having an injection cylinder chamber inside and having a resin injection nozzle at one end, an injection screw rotatably and axially movable in the injection cylinder chamber, A hydraulic motor that rotates the injection screw,
A rotary drive unit such as an electric motor, a hydraulic injection cylinder device for driving the injection screw in the axial direction, and a resin supply passage for supplying resin to the injection cylinder chamber; The resin is taken into the injection cylinder chamber from the resin supply passage by the screw pump action by being rotationally driven around its own central axis, and the injection cylinder is driven by the injection cylinder device to drive the injection screw in the axial direction. The resin taken into the chamber is configured to be injected from the resin injection nozzle toward the cavity of the molding die.

[0003]

In the screw type resin injection device, when the injection operation is temporarily stopped in a state where the resin remains in the resin supply passage and the injection cylinder chamber, the resin supply passage, The resin may be cured in the injection cylinder chamber.

When the resin is cured in the resin supply passage and the injection cylinder chamber, the subsequent injection work cannot be performed normally, and in this case, it is necessary to perform disassembly and cleaning. The disassembly washing is very troublesome and causes a significant decrease in production efficiency.

[0005] In particular, in the injection molding of a resin having a short pot life, such as a double-liquid reaction-curable resin such as silicone rubber, it is necessary to relatively frequently perform decomposition cleaning. .

The present invention has been made in view of the above-mentioned problems in the conventional screw-type resin injection apparatus for injection molding, and has been made in consideration of the above-mentioned problems. So that these washings for the elimination of can be performed easily and reliably without the need for disassembly.
It is an object of the present invention to provide an improved screw-type resin injection device for injection molding.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided an injection cylinder member having an injection cylinder chamber therein, a resin injection nozzle provided at one end, and an injection cylinder member. An injection screw arranged rotatably and axially movable, a plunger shaft fixedly connected to the injection screw and extending outward from the other end of the injection cylinder member, An electric motor that rotationally drives a plunger shaft with a rotary drive shaft that can be inserted into and removed from the plunger shaft, a fluid pressure cylinder device that axially drives the injection screw together with the plunger shaft, and a rotary valve in the injection cylinder chamber A resin supply passage for supplying a multi-component reaction-curable resin via a rotary valve, and a cleaning for selectively supplying a cleaning solvent to the resin supply passage via the rotary valve It has a solvent supply means is achieved by the injection molding screw resin injection device according to claim.

[0008]

According to the above construction, the cleaning solvent is supplied from the cleaning solvent supply means to the resin supply passage and further flows through the resin supply passage into the injection cylinder chamber and the like. Residual resin in the cylinder chamber and the like is eliminated.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 2 show an embodiment in which the screw-type resin injection device for injection molding according to the present invention is applied as an injection device for a reaction hardening type resin such as silicone rubber.

The screw type resin injection device for injection molding is
It has a cylinder fixing base 3 fixed on the forward / backward moving board 1, and the cylinder fixing base 3 holds the injection cylinder member 5 in a horizontal posture.

The injection cylinder member 5 forms an injection cylinder chamber 7 inside, and a tapered cylinder head member 9 for holding an injection nozzle is connected to one end on the same axis.

An injection screw 11 is disposed in the injection cylinder chamber 7 of the injection cylinder member 5 so as to be rotatable about its own central axis and movable in the axial direction. As shown in FIGS. 3 to 5, the injection screw 11 has a relatively large pitch, a triangular screw-shaped screw pump operating section 13 having a large lead angle, and is provided in front of the screw pump operating section 13. Screw pump action part 1
And a mixing screw portion 15 having a smaller pitch than that of No. 3 and a small lead angle. The mixing screw portion 15 has an even number of rectangular grooves 17 having a rectangular cross section having a depth equal to the screw height in the entire axial direction thereof, and in this embodiment, four axial grooves 17 at equal intervals in the circumferential direction. It is provided.

At the tip of the injection screw 11, FIG.
As shown in FIG. 8, a screw head member 19 is provided.
Are screwed and fixed, and a seal ring member 23 is externally fitted to the shaft portion 21 of the screw head member 19 so as to be movable in the axial direction. The seal ring member 23 is axially movable between a seal seat surface 25 formed by the distal end surface of the injection screw 11 and an end surface 27 of the screw head member 19 opposed thereto, as shown in FIG. By shutting off the communication between the nozzle side and the screw side of the injection cylinder chamber 7 by seating on the seal seating surface 25, the seating surface is seated on the end surface 27 as shown in FIG. 25, the shaft 21
In this embodiment, the nozzle side and the screw side of the injection cylinder chamber 7 are communicated with an odd number, in this embodiment, three cut grooves 35 formed in the head gap 33 and the head 33 of the screw head member 19. It is supposed to be. As described above, in this example, the number of the cut groove 35 and the number of the axial groove 17 are odd and even, and the phases are shifted from each other to facilitate the kneading. However, this is a relative relationship. Should just be shifted.

On the outer periphery of the seal ring member 23, two O-rings 37 are axially spaced from each other for sealing between the outer peripheral surface thereof and the inner peripheral surface of the injection cylinder chamber of the injection cylinder member 5. It is provided.

A nozzle device 39 with a valve is attached to the tip of the cylinder head member 9. As shown in FIG. 9, the valved nozzle device 39 includes a nozzle main body 43 inserted into the distal end hole 41 of the cylinder head member 9 so as to be movable in the axial direction, and a nozzle main body 43 in the injection cylinder chamber 7. A spool valve ring 47 which is circumscribed to the narrow shaft portion 45 of the small shaft portion 43 so as to be relatively displaceable in the axial direction, a valve seat member 49 fixed to the rear end of the thin shaft portion 45, and the nozzle body 43 are connected to the cylinder head member 9. And a compression coil spring 51 that urges the valve body 43 toward the valve closing side, that is, to the left side in the figure. By moving the valve seat member 49 relative to the head member 9 to the right in the drawing, the valve seat member 49 is separated from the contact with the spool valve ring 47 so that the valve hole 53 provided in the narrow shaft portion 45 in the radial direction is formed in the cylinder chamber. Let's expose 7 Going on. The valve hole 53 communicates with the guide hole 55 extending in the axial direction at the center of the nozzle body 43 and the nozzle hole 57 connected to the guide hole 55. It leads to the hole 57.

An O-ring 59 for sealing is provided on the outer periphery of the nozzle body 43.

As shown in FIGS. 1 and 2, an O-ring 61 is provided near the rear end of the injection screw 11 to prevent the resin from leaking backward.

A plunger shaft 63 is coaxially fixedly connected to the rear end of the injection screw 11. A reverse screw 6 for preventing the resin from leaking rearward is provided on the outer periphery of the portion where the plunger shaft 63 is fitted with the injection cylinder member 5.
The mechanical seal 67 is provided between the plunger shaft 63 and the cylinder fixing base 3.

The plunger shaft 63 is connected to the injection cylinder member 5.
Projecting rearward from the rear end, and this projection is rotatably and axially moved around its own central axis by a linear motion bearing 71 held by a bearing support member 69 fixed to the cylinder fixing base 3. Supported as possible.

A flange 73 is provided near the rear end of the plunger shaft 63, and the plunger shaft 63 in this portion is provided.
As shown in FIG. 2, the drive arm 7
One end of 5 is axially connected so as to be relatively rotatable with a needle thrust bearing 79 interposed between an end ring 77 fixedly mounted on the plunger shaft 63 and a flange 73.

As shown in FIG. 2, the drive arm 75 extends in the radial direction of the injection cylinder member 5 and is connected at its distal end to the distal end of the cylinder rod 83 of the pneumatic cylinder device 81. I have. The pneumatic cylinder device 81
It is arranged parallel to the side of the injection cylinder member 5 and is fixed to the side wall of the cylinder fixing base 3.

A shaft receiving hole 85 is formed at the rear end of the plunger shaft 63 so as to extend in the axial direction of the center of the plunger shaft 63 and open to the rear end surface of the plunger shaft 63. The rotary drive shaft 89 can be inserted into and removed from the shaft receiving hole 85 by a torque transmission type linear motion bearing 87, in other words, is fitted to the plunger shaft 63 in a telescopic manner in a torque transmitting relationship.

The rotation drive shaft 89 is connected to an output shaft 93 of a motor 91 fixed on the forward / backward moving board 1 by a coupling 95 in a torque transmitting relationship.

A resin supply block 97 is fixed to the cylinder fixing base 3. In this embodiment, as shown in FIG. 10, a resin material supply tube 99 also serving as a measuring cylinder is provided in the resin supply block 97 for injection molding of a two-component reaction-curable resin. Are mounted in parallel with each other. The resin material supply tube 99 has a resin supply block 97 having a resin discharge port 101 at the tip.
Is communicated with the resin passage 103 provided in the first passage. The resin passage 103 is connected to a resin passage 10 of the resin supply block 97 through a rotary valve 105 provided in the resin supply block 97.
7, a resin supply port 111 provided in the resin passage 109 of the cylinder fixing base 3 and an intermediate portion of the injection cylinder member 5
Is selectively communicated with.

The rotary valve 105 is of a manual type which is rotated by a manual lever 113. When the rotary valve 105 is in a rotating position as shown in FIGS. 1 and 11, when it is rotated clockwise by 90 degrees from the rotational position shown in FIGS. 1 and 11, the cleaning solvent passage 115 formed in the resin supply block 97 passes through the resin passage. 103 and the resin passage 107, and when they are turned 180 degrees in the drawing from the turning position as shown in FIGS. 1 and 11, the communication between the resin passage 103 and the resin passage 107 is cut off. The washing solvent passage 115 is connected to the resin passage 107, and when the washing solvent passage 115 is turned 270 degrees clockwise from the turning position shown in FIGS.
The communication between the cleaning solvent passage 115 and the resin passage 103 is interrupted by interrupting the communication between the cleaning passage 3 and the resin passage 107.

As shown in FIG. 11, each of the resin material supply tubes 99 has a resin intake port 117 at the tip end side, and each of the resin intake ports 117 is a liquid material from an individual resin material tank 119. Resin material is resin supply pipe 1
21, on-off valve 123, and resin supply pipe 125.

The cleaning solvent passage 115 communicates with a cleaning solvent supply port 127 provided in the resin supply block 97 so that the cleaning solvent is supplied from the cleaning solvent tank 129 via a cleaning solvent supply pipe 131. It has become.

A piston 133 is fitted in each of the resin material supply tubes 99, and the resin material in the resin material supply tube 99 is moved from the resin discharge port 101 by moving the piston 133 to the left in the drawing. The liquid is discharged to the passage 103.

In the resin supply block 97, a pneumatic cylinder device 135 for feeding the resin material is supplied with a resin material supply tube 99.
It is attached in parallel with. In the pneumatic cylinder device 135 for feeding resin material, a connecting plate 139 is attached to the tip of a piston rod 137, and one end of two push rods 141 is fixedly connected to the connecting plate 139, respectively. A push pad 143 is attached to each end of the push rod 141, and the push pad 143 is connected to the piston 1 of the resin material supply tube 99.
33, and is pressed to the left in the figure.

A U-shaped position detection rod 145 is attached to the push pad 143, and a switch support rod 147 is attached to the resin supply block 97 in parallel with the resin material supply tube 99. Proximity switches 149 and 151 that perform switching by proximity of a switch sensitive member 153 attached to the tip of the position detection rod 145 are attached to the switch support rod 147 so that the attachment position can be adjusted. As a result, the push pad 143 and, consequently, the resin material supply tube 99
The axial position of the piston 133 is monitored.

The forward / backward moving substrate 1 is connected to the moving table 157 of the rodless pneumatic cylinder device 155, and is moved forward and backward by the rodless pneumatic cylinder device 155.

In this embodiment, a cooling jacket 159 is attached to a portion where the injection cylinder member 5 is exposed to the outside on the front side to prevent the resin in the injection cylinder chamber 7 from hardening. ing.

According to the above-described configuration, when the resin is injected into the molding die M, first, the rotary valve 105 is moved to the position shown in FIG.
Alternatively, the pneumatic cylinder device 135 for feeding resin material is driven in the rotating position as shown in FIG.
The piston 133 of each resin material supply tube 99 is pressed leftward in the figure by each of the push rod 141 and the push pad 143, whereby the resin material of each resin material supply tube 99 is pushed to the resin passage 103 and the rotary valve 10.
5. Resin supply port 111 through resin passages 107 and 109
It is further fed into the injection cylinder chamber 7 of the injection cylinder member 5. In addition, the rotary drive shaft 8 is driven by the electric motor 91.
9 is driven to rotate, and the rotation thereof is transmitted to the plunger shaft 63 and the injection screw 11 by a torque transmission type linear motion bearing 87. As a result, they rotate around their own central axis, and the resin material fed into the injection cylinder chamber 7 is moved forward in the injection cylinder chamber 7 by the screw pump action of the screw pump action section 13 of the injection screw 11. That is, it is fed to the mixing screw part 15 by pressure.

Since the mixing screw portion 15 is provided with an axial groove 17 over the entire area in the axial direction, the resin material from each of the resin material supply tubes 99 fed to the mixing screw portion 15 has a compressive action. While receiving, a part flows along the screw groove of the mixing screw part 15, and the remaining resin material advances through each axial groove 17, etc., and a plurality of flows are generated. Occurs. Thereby, the kneading of the resin material from each resin material supply tube 99 is performed with high efficiency and uniformity.

The kneaded resin material reaches the tip of the injection screw 11, presses the seal ring member 23 to the left in the figure, and pushes it open to open the gap 29, the gap 31 and the screw head member 19. It flows to the nozzle side of the cylinder chamber 7 through the cut groove 35.

At this time, the seal ring member 23 does not rotate due to the resistance of the O-ring 37, but only the injection screw 11 and the screw head member 19 rotate.
The seal ring member 23 and the injection screw 11 rotate relative to each other. As a result, the seal ring member 23 is reliably opened, and the gap 29 as the resin passage is reliably secured.
Also, an O-ring 37 is separated from the sealing member 23 by two.
This is provided to prevent the injection cylinder 11 from being tilted with respect to the injection cylinder member 5 or the injection screw 11 and the head member 19 from being seized and hindering rotation.

When the resin material is filled in the nozzle side of the injection cylinder chamber 7, the reaction force acts on the injection screw 11 as a rightward force in the drawing, whereby the injection screw 11 and the plunger The shaft 63 is retracted rightward in the figure. This retreat is performed with low resistance under the guidance of the linear motion bearing 71, and the retreat increases the amount of the rotary drive shaft 89 entering the shaft receiving hole 85,
Even when the plunger shaft 63 and the rotation drive shaft 89 are relatively moved in the axial direction, the rotation of the rotation drive shaft 8
9 is driven by a torque transmitting linear motion bearing 87 by a drive plunger shaft 63 and an injection screw 1.
1 is transmitted without delay.

At this time, the injection screw 11 may be lightly driven together with the plunger shaft 63 by the pneumatic cylinder device 81 to assist the backward movement of the injection screw 11 to apply a retreat force to the injection screw 11. In this case, the plunger shaft 63 is rotating, but since the drive arm 75 and the plunger shaft 63 can be relatively rotated by the thrust needle bearing 77,
The rotational drive and the axial drive of the plunger shaft 63 are compatible with each other without any trouble.

When a predetermined amount of resin material is filled in the injection cylinder chamber 7, the injection screw 1
The rotation of 1 and the discharge of the resin material from the resin material supply tube 99 by the pneumatic cylinder device 135 are stopped, and then the forward and backward substrate 1 is moved forward by the rodless pneumatic cylinder device 155. Thereby, the cylinder fixing base 3,
The entirety of the injection cylinder member 5 and the injection screw 11 move forward, and as shown in FIG.
Is in contact with the molding die M, and the nozzle hole 57 is in contact with the molding die M.
Of the sprue S. When the forward / backward moving substrate 1 is further moved forward, the cylinder head member 9 moves forward with respect to the nozzle body 43, whereby the valve seat member 49 is separated from the contact with the spool valve ring 47 and the valve hole is moved. 53 is exposed to the injection cylinder chamber 7, and the injection cylinder chamber 7 communicates with the nozzle hole 57 via the guide hole 55.

Next, the injection screw 11 is driven forward by the pneumatic cylinder device 81. Then, first, due to the pressure of the resin material in the injection cylinder chamber 7, the seal ring member 23 moves backward with respect to the screw head member 19 and is seated on the seal seat surface 25, and the nozzle side and the screw side of the injection cylinder chamber 7 are moved. Communication is interrupted. Further, when the injection screw 11 is driven forward, this acts as a piston, and the forward thrust of the injection screw 11 by the pneumatic cylinder device 81 is converted into a resin material in the injection cylinder chamber 7 into an injection pressure. The resin material in the cylinder chamber 7 is injected from the nozzle hole 57 to the sprue S of the molding die M.

At this time, the resin material in the injection cylinder chamber 7 is filled with the outer periphery of the seal ring member 23 and the injection cylinder member 5.
The backflow leaks backward from the gap between the inner peripheral surface of the injection cylinder and the backflow, but this gap is sealed by the O-ring 37, so that the backflow is avoided. . As a result, pressure loss is eliminated, and a high injection pressure can be obtained. This means
It is particularly useful in the injection molding of a liquid resin having a low viscosity, a high fluidity and a tendency to cause backflow.

In the injection molding of a multi-liquid reaction-curable resin such as silicone rubber, the resin material mixed in the resin passages 107 and 109, the resin supply port 111, the injection cylinder chamber 7 and the like is kept for a certain period of time. When the injection is stopped for a certain period of time, the remaining resin in the resin passages 107 and 109, the resin supply port 111, the injection cylinder chamber 7 and the like must be removed. Therefore, the supply of the cleaning solvent is performed.

In this case, the rotary valve 105 is rotated by 180 degrees in the figure from the rotational position shown in FIG. 11, and the resin passage 107 is disconnected from the communication with the resin passage 103 to communicate with the cleaning solvent passage 115. Connecting.

In this state, the cleaning solvent in the cleaning solvent tank 129 is sent to the cleaning solvent supply port 127 by a pump (not shown) or the like. As a result, the cleaning solvent in the cleaning solvent tank 129 flows from the cleaning solvent supply port 127 to the resin passages 107 and 109, the resin supply port 111, and the injection cylinder chamber 7, and the resin material remaining in them flows into the cleaning solvent. Is washed away by

Although the present invention has been described in detail with reference to specific embodiments, the present invention is not limited to these embodiments, and various embodiments can be made within the scope of the present invention. Some will be apparent to those skilled in the art.

[0047]

As will be understood from the above description, according to the screw-type resin injection device for injection molding according to the present invention,
The cleaning solvent is supplied from the cleaning solvent supply means to the resin supply passage, further flows through the resin supply passage, and flows into the injection cylinder chamber, etc., thereby removing the residual resin in the resin supply passage, the injection cylinder chamber, etc. in a flushing manner. Since the cleaning is performed, the cleaning for eliminating the residual resin in the resin supply passage, the injection cylinder chamber, and the like can be easily and reliably performed without requiring a time-consuming disassembly. As a result, a decrease in production efficiency due to cleaning can be avoided.

[Brief description of the drawings]

FIG. 1 is a side view showing a partial cross section of an embodiment in which a screw-type resin injection device for injection molding according to the present invention is applied as an injection device for a multi-liquid reaction-curable resin such as silicone rubber.

FIG. 2 is a plan sectional view of a screw portion of the screw-type resin injection device for injection molding shown in FIG.

FIG. 3 is a perspective view showing an embodiment of an injection screw used in the screw-type resin injection device for injection molding according to the present invention.

FIG. 4 is a half sectional view showing an embodiment of an injection screw used in a screw-type resin injection device for injection molding according to the present invention.

FIG. 5 is a sectional view taken along the line VV in FIG. 4;

FIG. 6 is an enlarged sectional view showing one embodiment of a seal ring portion used in the screw-type resin injection device for injection molding according to the present invention in a closed state.

FIG. 7 is an enlarged cross-sectional view showing the seal ring portion shown in FIG. 6 in an open state.

FIG. 8 is a sectional view taken along the line VII-VII in FIG. 7;

FIG. 9 is a sectional view showing an embodiment of a valved nozzle device used in the screw-type resin injection device for injection molding according to the present invention.

FIG. 10 is an enlarged sectional view taken along line XX of FIG. 1;

FIG. 11 is a partial cross-sectional view showing one embodiment of a resin material supply portion of the screw-type resin injection device for injection molding according to the present invention.

[Explanation of symbols]

 Reference Signs List 5 injection cylinder member 7 injection cylinder chamber 11 injection screw 105 rotary valve 127 cleaning solvent supply port 129 cleaning solvent tank

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B29C 45/46-45/63 B29C 45/00

Claims (1)

(57) [Claims] 1. An injection cylinder member having an injection cylinder chamber formed therein and having a resin injection nozzle at one end, and an injection cylinder member rotatably and axially movable in the injection cylinder chamber. A screw, a plunger shaft fixedly connected to the injection screw and extending outward from the other end of the injection cylinder member, and a rotary drive shaft capable of inserting and removing the plunger shaft with respect to the plunger shaft. An electric motor that rotates and drives; a fluid pressure cylinder device that drives the injection screw in the axial direction together with the plunger shaft; and a resin supply passage that supplies a multi-liquid reaction-curable resin to the injection cylinder chamber via a rotary valve. And a cleaning solvent supply means for selectively supplying a cleaning solvent to the resin supply passage via the rotary valve. Screw-type resin injection device for out-molding.