JP4066057B1 - Electric vertical injection molding machine - Google Patents

Abstract

The height of the entire machine is reduced, the length of the ball screw shaft for raising and lowering the injection device is shortened, and the raising and lowering operation of the injection device is smoothly and easily controlled.
An electric vertical injection molding machine 1 includes a pair of support columns 4 erected on a movable platen 3 of a mold clamping device 2 and a pair of guide rails fixed to the support columns 4 in the vertical direction. 5, the injection device 7 supported by each guide rail 5 via a linear guide, and the injection device 7 is moved up and down along the guide rail 5 to move the injection nozzle 8 a of the heating cylinder 8 to the movable plate 3. An injection device lifting / lowering means 9 that contacts and separates from the movable mold is provided. The injection device lifting / lowering means 9 includes a ball nut 22 attached to a front plate 11 that holds the heating cylinder 8, and an upper end portion on the ball nut 22. And a motor 23 with a speed reducer that rotates the ball screw shaft 20 directly connected to the lower end thereof. Yes.
[Selection] Figure 6

Description

  The present invention relates to an electric vertical injection molding machine in which an injection device is erected on a movable plate of a vertical mold clamping device.

Conventionally, as an electric vertical injection molding machine, a plurality of guide shafts are erected on a movable plate, and a front plate of an injection device having a heating cylinder is supported and guided on the guide shaft. A nozzle touch operation in which the injection nozzle of the heating cylinder is brought into contact with the movable mold by moving the front plate up and down with respect to the movable plate by a plurality of cylinders that connect the cylinders (for example, Patent Document 1). Or by rotating a plurality of ball screw shafts with an electric motor installed on the top plate fixed to the upper end of the guide shaft, the upper hoisting plate supported by the guide shaft is moved up and down under the top plate. The nozzle touch operation is performed by raising and lowering the front plate connected under the upper elevator board. (For example, see Patent Document 2) are known.
However, the former electric vertical injection molding machine has a problem that a large working space cannot be secured around the heating cylinder because the guide shaft and the cylinder are erected from the movable platen. In the latter electric vertical injection molding machine, the front plate is moved up and down by the electric motor installed on the top plate at the upper end of the guide shaft, so that the entire machine There is a problem that the height becomes high. In addition, when the nozzle touch operation is performed by the injection device using a plurality of cylinders or a plurality of ball screw shafts as in each of the electric vertical injection molding machines, each cylinder or each ball screw Due to a shift in the operation timing between the axes, the nozzle touch operation may occur while the injection device is shaken, which may damage the injection nozzle or prevent the nozzle touch from being performed correctly.
Therefore, the vertical mold clamping device is supported on the middle horizontal portion of the main frame (support) standing on the installation surface, and two guide rails are provided on the vertical portion of the main frame above the mold clamping device. A ball that is arranged in the vertical direction and that is slidably supported on the guide rail through a linear guide on the base on which the injection device is assembled, and is operated by being directly connected to an electric motor fixed to the upper end of the main frame A structure in which the injection device is brought into contact with and separated from the movable mold attached to the movable plate at the upper end of the mold clamping device by moving the base up and down with a screw mechanism. Has also been proposed (see, for example, Patent Document 3).
Japanese Examined Patent Publication No. 6-69705 JP 2000-84988 A JP 2000-108157 A

  However, in the electric vertical injection molding machine described in Patent Document 3, the mold clamping device and the injection device are independently supported on the main frame, and an electric motor for raising and lowering the injection device is provided at the upper end of the main frame. The height of the entire machine is increased, and the length of the ball screw shaft of the ball screw mechanism is determined by the mold opening / closing distance of the mold clamping device and the vertical movement distance of the injection device. Combined and lengthened. In addition, since it is necessary to appropriately adjust the raising / lowering timing and raising / lowering speed of the injection device with respect to the mold opening / closing operation of the mold clamping device, there is a problem that the rotation control of the servo motor becomes complicated.

  The present invention has been made in view of the above circumstances, and is capable of reducing the height of the entire machine, shortening the length of the ball screw shaft for raising and lowering the injection device, and smoothing the raising and lowering operation of the injection device. Another object of the present invention is to provide an electric vertical injection molding machine that can easily perform the control.

In order to solve the above problems, the present invention has the following configuration.
In other words, the electric vertical injection molding machine according to claim 1 includes a pair of struts erected on a movable plate of a vertical mold clamping device, and a pair of struts fixed to the respective struts in the vertical direction. A guide rail, an injection device supported by each guide rail via a linear guide, and an injection device of the heating cylinder fixed to the movable plate by moving the injection device up and down along the guide rail. An electric vertical injection molding machine provided with an injection device lifting / lowering means for contacting and separating from the movable mold,
The injection device lifting / lowering means is formed by screwing a ball screw shaft into a ball nut and connecting the front plate of the injection device that holds the heating cylinder and the movable plate to face the vertical direction. A single ball screw mechanism;
Rotation drive supported by the movable platen, connected to the lower end of the ball screw mechanism, and rotating one of the ball nut and the ball screw shaft to raise and lower the injection device including the front plate with respect to the movable platen Means and
The injection device includes: the front plate that holds the heating cylinder; the linear motion guide; a pusher plate that rotatably holds the injection screw; and an injection device that moves the injection screw forward and backward through the pusher plate. A motor and a screw rotation motor for rotating the injection screw;
The ball screw mechanism is characterized in that its axis is located at the center of gravity of the injection device.

  The electric vertical injection molding machine according to claim 2 is the electric vertical injection molding machine according to claim 1, wherein the ball screw shaft of the ball screw mechanism has the axis centered in plan view. It arrange | positions on the line | wire which connects the center between these guide rails, and the center of the said heating cylinder.

  The electric vertical injection molding machine according to claim 3 is the electric vertical injection molding machine according to claim 1 or 2, wherein the ball nut is attached to a front plate, and the ball screw shaft is at its upper end. The screw nut is screwed to the ball nut, and the lower end thereof is supported on the movable plate so as to be rotatable around the shaft. The rotation driving means is directly connected to the lower end of the ball screw shaft to rotate the ball screw shaft. It is characterized by having.

  An electric vertical injection molding machine according to claim 4 is the electric vertical injection molding machine according to any one of claims 1 to 3, wherein the rotation driving means rotates around a horizontal axis. And a speed reducer that inputs the rotation of the electric motor to the horizontal axis and decelerates and then outputs it to the vertical axis directed in the vertical direction, and the vertical axis is connected to the ball screw axis. It is characterized by being.

The electric vertical injection molding machine according to claim 5 is the electric vertical injection molding machine according to claim 3 or 4, wherein the ball nut is movable up and down by a predetermined distance with respect to the front plate. The support member is urged so as to be always pressed against the lower end of the front plate by a spring disposed between the support plate and the support plate connected to the front plate via the support shaft. Between the members , there is provided a detecting means for detecting that the injection nozzle of the heating cylinder is in contact with the movable mold at a predetermined pressure.

The present invention has the following excellent effects.
That is, according to the electric vertical injection molding machine of the first aspect, the injection device is supported by the guide rail fixed to the support column standing on the movable plate of the mold clamping device so as to be movable up and down via the linear motion guide. Since the ball screw shaft or the ball nut is rotated by the rotation driving means at the lower end of the ball screw mechanism for raising and lowering the injection device, the mold clamping device and the injection device are independently placed on a common support as in the conventional case. It is not necessary to adopt a configuration in which a rotation driving means for supporting and rotating the ball screw shaft of the ball screw mechanism for raising and lowering the injection device is fixed to the upper end of the support column, and the height of the entire machine can be reduced. By lowering the movable platen in the mold-clamping state, the entire machine can be easily transported at a reduced height. Further, the ball screw shaft for raising and lowering the injection device does not need to be extended to the moving distance of the injection device plus the mold opening / closing distance, and the length can be shortened by that amount, and the mold of the mold clamping device can be reduced. It is not necessary to adjust the raising / lowering timing and raising / lowering speed of the injection device with respect to the opening / closing operation, and it is possible to easily control the raising / lowering operation of the injection device by the rotation driving means of the ball screw shaft.
Moreover, since the axis of the ball screw mechanism is located at the center of gravity of the injection device, the ball screw mechanism can be moved up and down to the injection device including the front plate with the load applied to the injection device applied evenly. Combined with the firm support rigidity by the moving guide, it is possible to prevent the injection device from swinging and to move up and down smoothly.

  According to the electric vertical injection molding machine according to claim 2, the ball screw shaft is in the center of the pair of guide rails, and the load applied to the front plates of the injection device is applied to both guide rails evenly. Since the front plate can be moved up and down, coupled with the solid support rigidity by the linear motion guide with respect to the guide rail, it is possible to prevent the injection device from shaking and raise and lower it smoothly.

  Further, according to the electric vertical injection molding machine according to claim 3, since it is not necessary to rotate the ball nut having a large diameter, the structure of the connecting portion between the ball screw shaft and the rotation driving means can be compactly gathered. In addition, the driving force of the ball screw mechanism can be reduced and the nozzle touch operation of the injection device can be performed quickly.

  Further, according to the electric vertical injection molding machine according to claim 4, since the electric motor does not have to be arranged in the extending direction of the lower end of the ball screw shaft, the ball screw shaft is placed on the upper surface of the movable plate accordingly. They can be arranged close to each other, and the height of the entire machine can be kept low from this point.

Further, according to the electric vertical injection molding machine according to the fifth aspect of the present invention, the detection nozzle provided between the support plate and the support member detects the amount of deflection of the spring, so that the injection nozzle of the heating cylinder is movable. Since it is possible to quickly stop the forward movement of the injection device after confirming that it is in contact with the mold at a predetermined pressure, the injection device is prevented from striking and the injection nozzle contacts the movable mold with excessive pressure. Can be surely prevented, and impact at the time of nozzle touch can be reduced.

Hereinafter, an electric vertical injection molding machine according to an embodiment of the present invention will be described with reference to the accompanying drawings.
1 to 7, reference numeral 1 denotes an electric vertical injection molding machine according to an embodiment of the present invention. The electric vertical injection molding machine 1 has a pair of support columns 4 and 4 erected on a movable plate 3 of a vertical mold clamping device 2 and is fixed to the support columns 4 and 4 in the vertical direction. A pair of guide rails 5, 5, an injection device 7 supported by the guide rails 5, 5 via linear motion guides (linear guides) 6, 6, and a guide rail And an injection device lifting / lowering means 9 for moving the injection nozzle 8a at the tip of the heating cylinder 8 into and out of contact with a movable mold (not shown) fixed to the movable plate 3 by moving up and down along 5 and 5. I have.

  Although the mold clamping device 2 is not shown, for example, a fixed platen is fixed to the upper surface of the machine base, and a triangle positioned above the fixed plate is provided at the upper ends of three tie bars 2a penetrating the fixed plate up and down. The movable plate 3 having a shape is fixed near the top of the triangle, an end plate is fixed to the lower end of the tie bar 2a, the end plate and the fixed plate are connected by a toggle mechanism, and the toggle mechanism is servoed. By extending and contracting with a motor and a ball screw mechanism, or by directly connecting the end plate and the fixed plate with a ball screw mechanism without using a toggle mechanism, and operating the ball screw mechanism with a servo motor, The movable plate 3 is moved up and down with respect to the fixed plate via the end plate and the tie bar 2a, and a fixed mold and a movable die attached to the fixed plate and the movable plate 3 are provided. DOO closing, those well known conventional configured to perform mold clamping.

  Each of the columns 4 and 4 has rail support members 4a and 4a fixed to the front surfaces thereof (the front side surface in FIG. 1, the right side surface in FIGS. 2 and 6 and the lower side surface in FIGS. 3 to 5) over substantially the entire length. The lower end of the rail support members 4a and 4a is fixed to the upper surface of the movable plate 3 with a bolt 10a. The rear surface of the bracket 10 is the rear surface (the other side in FIG. 1, the left side in FIGS. 2 and 6, and FIGS. 5 is fixed to the upper side surface by bolts 10b, and are erected in parallel with each other. The upper end portions are connected to each other by a horizontal beam 4b to form a gate shape. And the guide rails 5 and 5 are fixedly supported along the support | pillars 4 and 4 by attaching the said guide rails 5 and 5 with the volt | bolt 5a to the front surface in the upper side of the said rail support members 4a and 4a. Yes.

  The injection device 7 is provided with a front plate 11 that is horizontally arranged in a rectangular shape in a plan view in which the heating cylinder 8 is held vertically (in the vertical direction). A pair of upper and lower linear motion guides 6 and 6 fixed to each other are fitted and supported on each of the guide rails 5 and 5 with a ball or a roller interposed therebetween so as to move up and down along the guide rails 5 and 5. It has become. Above the front plate 11, a rotating shaft 13 connected to an injection screw 12 inserted in the heating cylinder 8 so as to be rotatable in the circumferential direction and movably in the axial direction is rotatably held by a bearing 13a. The pusher plate 14 is provided in parallel with the front plate 11 at an interval. The pusher plate 14 moves up and down along the guide rails 5 and 5 by fitting and supporting the linear guides 6 and 6 fixed on both sides of the back surface of the pusher plate 14 to the guide rails 5 and 5. ing. A pair of ball screw shafts (injection ball screw shafts) 15 and 15 located on both sides of the heating cylinder 8 and extending vertically upward are rotatable on the upper portion of the front plate 11. Ball nuts 16, 16 screwed onto the ball screw shafts 15, 15 are fixed at positions on the pusher plate 14 on the axis of the ball screw shafts 15, 15.

  Further, an injection screw forward / reverse electric servomotor (injection motor) 17 with the output shaft facing upward is attached to the back side of the front plate 11 and is fixed to the output shaft of the injection motor 17. When the belt 17b is wound around the pulley 17a and the pulleys 15a and 15a fixed to the ball screw shafts 15 and 15, and the injection motor 17 rotates, the pusher plate 14 is moved with respect to the front plate 11, The injection screw 12 moves forward and backward in the heating cylinder 8. Further, a screw rotating electric servomotor (screw rotating motor) 18 with an output shaft facing downward is attached to the back side of the pusher plate 14, and a pulley fixed to the output shaft of the screw rotating motor 18. When the belt 18b is wound around the pulley 13b fixed to the rotary shaft 13a and the screw rotating motor 18 is rotated, the injection screw 12 is rotated. 2, 4, and 7, reference numeral 15 b denotes an idler pulley that guides and tensions the belt 17 b.

A bearing box 19 is detachably fixed to the support portion 10c provided at the intermediate portion in the vertical direction of the bracket 10 via a flange portion 19a. One directed ball screw shaft (nozzle touch ball screw shaft) 20 is supported by a bearing 21 at its lower end, and is provided so as to be freely rotatable about the shaft in an axial direction. A ball nut 22 that is screwed onto the ball screw shaft 20 is attached to the front plate 11 on the axis of the ball screw shaft 20.
The ball screw shaft 20 and the ball nut 22 constitute a ball screw mechanism for nozzle touch, and as shown in FIGS. 3 and 4, the shaft center C of the pair of guide rails 5 and 5 is seen in a plan view. Arranged on a straight line L connecting the center between them and the center C1 of the heating cylinder 8, slightly closer to the heating cylinder 8 than the position of the guide surfaces of the guide rails 5 and 5, but close to the guide surface Has been. The injection motor 17 and the screw rotation motor 18 have their axes aligned with the straight line L at a position spaced apart from the heating cylinder 8 with the axis C therebetween. By being arranged, the position of the axis C is in the vicinity of the center of gravity of the injection device 7.

  A motor with a speed reducer (rotary drive means) 23 is directly connected to the lower end of the ball screw shaft 20 without interposing a transmission mechanism such as a pulley or a belt. That is, the motor 23 with a speed reducer includes an electric motor 23a composed of a servo motor that rotates around a horizontal axis, and a plurality of reduction gears including a bevel gear or a hypoid gear by inputting the rotation of the electric motor 23a to the horizontal axis. And a speed reducer 23b that outputs to a vertical axis S directed in the up-down direction after being decelerated via the speed reducer 23b is attached to the lower end of the bearing housing 19, and the vertical axis S is It is connected to the lower end of the ball screw shaft 20.

  A pair of support shafts 24, 24 are fixed to the lower surface of the front plate 11 so as to be located on both sides of the ball screw shaft 20 and project downward. A support plate 25 is suspended from the lower ends of the support shafts 24, 24. On the upper end side of the support shafts 24, 24, a flat plate-like support member 26 is provided so as to move up and down by fitting a pair of shaft holes to the support shafts 24, 24, and the support plate 25. A pair of compression springs (springs) 27, 27 mounted on the respective support shafts 24, 24 are interposed between the support member 26 and the support member 26, and the support member 26 is always in contact with the urging force of the compression springs 27, 27. It is pressed against the lower surface of the front plate 11. The ball nut 22 is inserted into the center hole of the support member 26 through the cylindrical portion, and then fitted into the fitting hole 11a of the front plate 11, and fixed to the support member 26 with a bolt via the flange portion 22a. Has been. That is, the ball nut 22 is fixed to the front plate 11 so as to move up and down by a predetermined distance while being urged so as to be constantly pressed against the lower end of the front plate 11 by the compression springs 27 and 27. It is attached.

A pair of non-contact type limit switches 28a and 28b are shifted by a small distance in the length direction of the ball screw shaft 20 on one side (right side in FIG. 7) of the support plate 25. On the other hand, operating pieces 29a and 29b made of bolts are fixed to one side of the support member 26 so as to be adjustable in the length direction of the ball screw shaft 20, respectively.
The motor 23 with speed reducer, the bearing box 19, the ball screw shaft 20, the ball nut 22, the support shaft 24, the support plate 25, the support member 26, the compression spring 27, and the like make the injection device 7 into the guide rails 5 and 5. An injection device lifting / lowering means 9 for moving the injection nozzle 8a of the heating cylinder 8 in contact with and moving away from a movable mold (not shown) fixed to the movable plate 3 to perform a nozzle touch operation It is composed.

Next, the operation of the electric vertical injection molding machine 1 configured as described above will be described.
At the start of the molding operation, etc., the ball screw shaft 20 is rotated by rotating the motor 23 with a speed reducer and rotating the ball screw shaft 20 in a state indicated by a solid line in FIGS. The front plate 11 is lowered through the ball nut 22 screwed to the heating plate 8, and the injection nozzle 8a of the heating cylinder 8 is lowered to the position indicated by the chain line and is attached to the movable platen 3 so as to contact the movable mold. The nozzle touch operation is performed in contact. In this nozzle touch operation, after the injection nozzle 8a comes into contact with the movable mold, the support member 26 is slightly lowered against the urging force of the compression springs 27, 27 through the ball nut 22, It is detected that the limit switch 28a mounted on the upper side of the support plate 25 is operated by the operating piece 29a of the support member 26, so that the injection nozzle 8a contacts the movable mold. Further, the support member 26 further descends against the urging force of the compression springs 27, 27 from this position, so that the limit switch 28 b attached to the lower position of the support plate 25 is attached to the support plate member 26. When the deflection amount of the compression springs 27, 27 is detected by the operation piece 29b, the injection nozzle 8a comes into contact with the movable mold by a predetermined pressure based on the urging force of the compression springs 27, 27. At this time, the reduction gear motor 23 is stopped, whereby the lowering of the front plate 11 is quickly stopped.

  When the nozzle touch operation is performed and the fixed mold and the movable mold are clamped between the movable platen 3 and the fixed platen by the mold clamping device 2, the screw rotation motor 18 is operated. By rotating the injection screw 12 via the pulleys 18a and 13b and the belt 18b, the resin material supplied into the heating cylinder 8 from the hopper provided on the base end (upper end) side of the heating cylinder 8 is obtained. After being melted and kneaded, the molten resin is measured in the resin reservoir portion on the tip end side of the heating cylinder 8. At this time, the injection motor 17 is rotated and the ball screw shafts 15 and 15 are rotated via the pulleys 15a and 17a and the belt 17b, so that the pusher plate 14 is lifted via the ball nuts 16 and 16. Thereby, the injection screw 12 moves backward while applying a back pressure to the molten resin.

When the injection screw 12 is moved back to the measurement completion position, the rotation of the screw rotation motor 18 is stopped, the injection screw 12 is stopped, and the injection motor 17 is rotated in the opposite direction to the above. The injection screw 12 is advanced through the pusher plate 14, and the molten resin measured in the heating cylinder 8 is injected into a mold cavity formed by a movable mold and a fixed mold, and molding is performed.
During the nozzle touch operation, the ball screw shaft 20 of the ball screw mechanism is on a straight line L that connects the center between the pair of guide rails 5 and 5 and the center of the heating cylinder 8 in plan view with the axis C. Since the ball screw shaft 20 is located in the center of the pair of guide rails 5 and 5 and the load applied to the front plate 11 of the injection device 7 is evenly distributed to both the guide rails 5 and 5 because the ball screw shaft 20 is disposed near the center of gravity of the injection device 7. The front plate 11 can be lifted and lowered in the acted state, and, in combination with the solid support rigidity by the linear motion guide with respect to the guide rail, the injection device can be lifted and lowered smoothly while preventing its shaking. it can.

  The ball nut 22 is attached to the front plate 11 so as to move up and down by a predetermined distance while being urged so as to be constantly pressed against the lower end of the front plate 11 by the compression springs 27, 27. The compression spring 27 provided between the front plate 11 (support plate 25) and the ball nut 22 (support member 26) effectively applies an impact at the time of nozzle touch where the injection nozzle 8a of the cylinder 8 contacts the movable mold. Can be buffered. Further, between the front plate 11 and the ball nut 22, a pair of limit switches 28a and 28b for detecting that the injection nozzle 8a of the heating cylinder 8 is in contact with the movable mold at a predetermined pressure are operated. Since the detection means comprising the pieces 29a and 29b is provided, the advancement movement of the injection device can be stopped quickly by confirming that the injection nozzle 8a has surely contacted the movable mold by the detection means. In this way, it is possible to prevent the injection device 7 from coasting and to reliably prevent the injection nozzle 8a from coming into contact with the movable mold with excessive pressure, and to reduce the impact when the nozzle touches. it can.

  As described above, the electric vertical injection molding machine 1 according to the embodiment includes the pair of support columns 4 and 4 erected on the movable platen 3 of the vertical mold clamping device 2 and each of the support columns. A pair of guide rails 5, 5 fixed to the upper and lower sides of the guide rails 4, 4, an injection device 7 supported by the guide rails 5, 5 via the linear motion guides 6, 6 so as to be movable up and down, An injection device raising / lowering means 9 for raising and lowering the injection device 7 along the guide rails 5 and 5 to bring the injection nozzle 8a of the heating cylinder 8 into contact with and away from the movable mold fixed to the movable platen 3. The injection device lifting / lowering means 9 includes a ball nut 22 and a ball screw shaft 20 screwed together, and connects the front plate 11 of the injection device 7 that holds the heating cylinder 8 and the movable plate 3 to move up and down. A ball screw mechanism arranged in the direction and supported by the movable platen 3 A motor 23 with a speed reducer which is directly connected to the lower end of the ball screw mechanism and rotates the one of the ball nut 22 and the ball screw shaft 20 to move the front plate 11 up and down with respect to the movable platen 3; It is configured.

  Therefore, according to the electric vertical injection molding machine 1 according to the above-described embodiment, the injection device 7 is attached to the guide rails 5 and 5 fixed to the support columns 4 and 4 erected on the movable plate 3 of the mold clamping device 2. Since the ball screw shaft 20 of the ball screw mechanism for raising and lowering the injection device is rotated by the motor 23 with a speed reducer at the lower end thereof, the die screw is supported by the linear motion guides 6 and 6 so as to be movable up and down. There is no need to adopt a configuration in which the fastening device and the injection device are independently supported on a common column, and a rotation driving means for rotating the ball screw shaft of the ball screw mechanism for raising and lowering the injection device is fixed to the upper end of the column. Thus, the height of the entire machine can be reduced. In particular, by lowering the movable platen 3 in a mold-clamping state, the overall height of the machine can be reduced and transported easily. Further, the ball screw shaft 20 for raising and lowering the injection device does not need to be extended to the moving distance of the nozzle touch operation plus the mold opening / closing distance, and the length can be shortened by that much, and the mold clamping device It is not necessary to adjust the raising / lowering timing and raising / lowering speed of the injection device 7 with respect to the mold opening / closing operation of the mold 2, and the control of the raising / lowering operation of the injection device 7 by the motor 23 with a reducer of the ball screw shaft 20 can be easily performed. It can be carried out.

  The motor 23 with a reduction gear is an electric motor 3a that rotates about a horizontal axis, and a deceleration that outputs the rotation of the electric motor 23a to the vertical axis S in the vertical direction after the rotation is input to the horizontal axis and decelerated. Since the vertical shaft S is connected to the lower end of the ball screw shaft 20, the electric motor 23 a is arranged in the extending direction of the lower end of the ball screw shaft 20. The ball screw shaft 20 can be disposed closer to the upper surface of the movable platen 3 and the height of the entire machine can be reduced from this point.

  In the electric vertical injection molding machine 1 according to the embodiment, the ball nut 22 is attached to the front plate 11, and the ball screw shaft 20 is screwed into the ball nut 22 at its upper end. The lower end portion is supported on the movable plate 3 so as to be rotatable around the shaft, and the motor 23 with a speed reducer is directly connected to the lower end of the ball screw shaft 20 so that the ball screw shaft 20 is rotated. It is not necessary to rotate the ball nut, and the structure of the connecting portion between the ball screw shaft 20 and the motor 23 with the speed reducer can be compactly combined, and the driving force of the ball screw mechanism can be reduced to reduce the driving force of the injection device 7. The nozzle touch operation can be performed quickly. However, the configuration is not limited thereto, and the ball nut 22 is supported by the movable plate 3 and the screw shaft 20 is attached to the front plate 11. In this case, a flange is provided at the upper end portion of the ball screw shaft 20 and the flange is fixed to the support member and fixed in a circumferential direction so as to be movable up and down by a predetermined distance. It is fixed in the axial direction and is rotatably supported around the shaft and is connected to the motor 23 with a speed reducer.

It is the front view which showed the electric vertical injection molding machine which concerns on one embodiment of this invention in the partial cross section. FIG. FIG. 2 is a view taken in the direction of arrow B in FIG. 1. FIG. 2 is a cross-sectional view of FIG. FIG. 2 is a cross-sectional view of the knee of FIG. 1. FIG. 2 is a sectional view of the hoe of FIG. 1. FIG. 7 is a cross-sectional view taken along a partial cross section of FIG. 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric vertical injection molding machine 2 Clamping device 3 Movable platen 4 Support column 5 Guide rail 6 Linear motion guide 7 Injection device 8 Heating cylinder 8a Injection nozzle 9 Injection device raising / lowering means 10 Bracket 11 Front plate 12 Injection screw 14 Pusher plate 15 , 20 Ball screw shaft 16, 22 Ball nut 17 Electric servo motor for screw forward / backward movement (injection motor)
18 Electric servo motor for screw rotation (Motor for screw rotation)
19 Bearing box 23 Motor with reduction gear (rotary drive means)
24 Support shaft 25 Support plate 26 Support member 27 Compression spring (spring)
28a, 28b Limit switch (detection means)
29a, 29b Actuating piece (detection means)

Claims (5)

A pair of struts erected on the movable platen of the vertical mold clamping device, a pair of guide rails fixed to the respective struts in the vertical direction, and ascending and descending to each guide rail via a linear guide An injection device supported freely, and an injection device raising / lowering means for raising and lowering the injection device along the guide rail so that the injection nozzle of the heating cylinder comes into contact with and separates from the movable mold fixed to the movable platen An electric vertical injection molding machine equipped with
The injection device lifting / lowering means is formed by screwing a ball screw shaft into a ball nut and connecting the front plate of the injection device that holds the heating cylinder and the movable plate to face the vertical direction. A single ball screw mechanism;
Rotation drive supported by the movable platen, connected to the lower end of the ball screw mechanism, and rotating one of the ball nut and the ball screw shaft to raise and lower the injection device including the front plate with respect to the movable platen Means and
The injection device includes: the front plate that holds the heating cylinder; the linear motion guide; a pusher plate that rotatably holds the injection screw; and an injection device that moves the injection screw forward and backward through the pusher plate. A motor and a screw rotation motor for rotating the injection screw;
The ball screw mechanism has an axis centered at the center of gravity of the injection device, and is an electric vertical injection molding machine.   The ball screw shaft of the ball screw mechanism is arranged on a line connecting the center between the pair of guide rails and the center of the heating cylinder in plan view. Electric vertical injection molding machine.   The ball nut is attached to the front plate, the ball screw shaft is screwed at its upper end to the ball nut, and its lower end is supported on the movable plate so as to be rotatable around the shaft, and is attached to the lower end of the ball screw shaft. The electric vertical injection molding machine according to claim 1 or 2, wherein the rotation driving means is directly connected to rotate the ball screw shaft.   The rotation driving means is integrally assembled with an electric motor that rotates about a horizontal axis, and a speed reducer that inputs the rotation of the electric motor to the horizontal axis and decelerates it, and then outputs it to the vertical axis in the vertical direction. The electric vertical injection molding machine according to any one of claims 1 to 3, wherein the vertical shaft is connected to the ball screw shaft. The ball nut is fixed to a support member that can move up and down by a predetermined distance with respect to the front plate, and the support member is provided by a spring disposed between a support plate connected to the front plate via a support shaft. It is urged so as to be always pressed against the lower end of the front plate, and detects that the injection nozzle of the heating cylinder abuts the movable mold with a predetermined pressure between the support plate and the support member. The electric vertical injection molding machine according to claim 3 or 4, further comprising a detecting means for performing the operation.

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