JP3517747B2 - Drive unit and injection molding machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for rotating a plurality of rotary members in synchronization with each other by a plurality of drive motors, and an injection molding machine equipped with the drive device.

[0002]

2. Description of the Related Art In an electric injection molding machine, two driving motors are often used to rotate two rotary members of the same apparatus as the size of the electric injection molding machine is increased. In such a case, conventionally, as shown in FIG. 7, as shown in FIG. 7, the drive pulleys 83 and 84 of the drive motors 81 and 82 and the rotary members 8 are provided.
Timing belts 89 and 90 are respectively wound around the driven pulleys 87 and 88 of the motors 5 and 86 to drive the drive motors 81 and 8 respectively.
2 the rotary members 85 and 86 to the timing belts 89 and 9
Or rotate independently through 0, or
As in Japanese Unexamined Patent Publication No. 128724, drive pulleys are directly connected to the rotary members so that the rotary members can also be rotated independently.

[0003]

However, in any case, if the rotations of the drive motors 81 and 82 are synchronized only by the control system thereof, and if a failure occurs in the control system, a plurality of rotating members are provided between them. Unbalanced load occurs and causes a big trouble,
Since some mechanical synchronizer must be provided, there is a problem that the whole structure becomes complicated and the cost becomes high.
In addition, in the latter direct drive system drive device, in addition to the above, in order to move the pusher plate forward at a speed suitable for injection, the drive motor must be operated at a rotational speed lower than the rated rotational speed. As described above, there is a problem that a drive motor having a large output is required.

Therefore, as shown in FIG. 8, it is conceivable to wind one timing belt 91 around two driving pulleys 83 and 84 and two driven pulleys 87 and 88. By doing so, the above problems are temporarily solved, but the timing belt 91 having a high strength and a long length is provided.
Is required, and the cost is increased in another aspect.

It is an object of the present invention to provide a drive unit and an injection molding machine that can rotate a plurality of rotating members in a precisely synchronized manner without separately providing a synchronizing device. Another object of the present invention is to provide a drive unit and an injection molding machine which have a simple structure and are inexpensive.

[0006]

In order to achieve at least one of the above objects, the invention as claimed in claim 1 has a plurality of drive motors, each drive motor having a common drive pulley .
When a plurality of rotating members supported by the supporting member and respectively provided with driven pulleys are rotatably provided on the supporting member.
In addition, in each of the drive devices for rotating the rotating members in synchronization with each other via the same number of belt bodies as the drive motors, which are wound around the drive pulleys and the driven pulleys by the drive motors, the belt body, it
Is, different one drive motor of the drive pulley and the
It is configured to be wound around the driven pulley of each rotating member .

In the above means, the rotation of each drive motor is
Each is transmitted to two or more rotating members via one belt body. Therefore, each belt body also functions as a synchronization unit, and all the rotating members rotate in synchronization with each other. Since each belt body only transmits the rotation of the drive pulley of one drive motor to the driven pulleys of two or more rotating members, and is independent of the drive pulleys of other drive motors, it drives all drive pulleys and driven pulleys. It is possible to use a belt body having a weak strength and a short length as compared with the case of being wound around a pulley.

In the above drive device, the number of drive motors and the number of rotary members can each be two (claim 2). This structure is the simplest drive device. Also,
Each drive motor may be a servo motor (claim 3). With this configuration, it is possible to accurately control the rotating member.

According to a fourth aspect of the present invention, a plurality of drive motors each having a drive pulley are provided on one common support member.
Multiple rotating members supported and each having a driven pulley
Is rotatably provided on the support member, and
In an injection molding machine equipped with a drive device that rotates each of the rotating members in synchronization with each other via the same number of belt bodies as the drive motor, which is wound around the drive pulley and the driven pulley by each drive motor . The drive device is the drive device according to any one of claims 1 to 3.

In the above means, when the plurality of drive motors are operated, the plurality of rotary members rotate in exactly synchronization with each other, and the operation of the injection molding machine by the drive device is smoothly and reliably performed.

In the above injection molding machine, the drive unit is
It can be used as a driving device of a screw mechanism of a mold clamping device that moves a movable plate (claim 5). In this case, the plurality of rotating members of the screw mechanism rotate in synchronization with each other to move the movable plate of the mold clamping device.

Further, the drive device may be a drive device of a screw mechanism of the injection device for moving the pusher plate provided with the injection screw (claim 6). In this injection molding machine, a plurality of rotating members of the screw mechanism rotate in synchronization with each other to move the pusher plate of the injection device.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the accompanying drawings. 1 and 2 show an embodiment of a drive device according to the present invention. Reference numerals 1 and 2 are drive motors composed of electric motors such as servomotors. The drive motors 1 and 2 are supported side by side on a support member 4, and their output shafts 1a and 2a are driven by drive pulleys 5 and 6, respectively.
Have.

Below the drive motors 1 and 2, rotary members 8 and 9 such as rotary shafts are rotatably supported by the support member 4 and provided, respectively. Each rotating member 8 and 9 has a driven pulley 10 and 11, respectively. The drive pulleys 5 and 6 of the respective drive motors 1 and 2 are arranged so as to be offset from each other in the front-rear direction so that they do not overlap each other in their side views, and the driven pulleys 10 and 11 are arranged in relation to each other in their side view. The front and rear positions are aligned so as to overlap with each other, and are arranged so as to overlap with both drive pulleys 5 and 6 in a plan view.

An endless belt member 13 such as a timing belt or a chain is wound around the drive pulley 5 of the drive motor 1 and the driven pulleys 10 and 11 of the rotary members 8 and 9, and the drive motor 2 An endless belt member 14 such as a timing belt or a chain is wound around the drive pulley 6 and the driven pulleys 10 and 11 of the rotating members 8 and 9.

Each pair of drive motors 1, 2, drive pulleys 5, 6, rotating members 8, 9, driven pulleys 10, 1
1, the belt bodies 13 and 14 are the same,
They are arranged symmetrically when viewed from the front.

In the drive unit A, when the drive motors 1 and 2 are operated to rotate the drive pulleys 5 and 6 in the same direction, for example, clockwise, the drive pulley 5 rotates via the belt body 13. While being transmitted to the driven pulleys 10 and 11, the rotation of the other drive pulley 6 is transmitted to the driven pulleys 10 and 11 via the other belt body 14. Therefore, the pair of rotating members 8 and 9 rotate clockwise in synchronization with each other.

As described above, the belt bodies 13 and 14 not only transmit the rotations of the drive pulleys 5 and 6 to the driven pulleys 10 and 11, respectively, but also act as synchronizing means to drive the driven pulleys 1 and 2.
Since the rotations of 0 and 11 are accurately synchronized, it is not necessary to separately provide a synchronizing device. In addition, each belt body 13, 14
8 is different from the belt-type drive device of FIG. 8 in that the powers of the drive motors 1 and 2 are separately supplied to the rotating members 10 and 11, respectively.
Since it is only transmitted to the side, it is not necessary to use a belt body having a particularly strong strength and a long length.

In the drive device of the present invention, the number of equipments of the drive motor and / or the rotary member can be three or more. Further, the driven pulleys 10 and 11 in the figure are the belt members 1
Although the winding parts 3 and 14 are integrated with each other, a plurality of winding parts may be separated from each other.

Timing belts are generally used as the belt members 13 and 14. When a V-belt or a flat belt is used for the belt bodies 13 and 14, the slip amount tends to be large, and when the belt bodies 13 and 14 are chains, a tension pulley is required because they are easily stretched, which complicates the structure. Although easy, a V belt, a flat belt or a chain may be used. It goes without saying that the drive pulleys 5, 6 and the driven pulleys 10, 11 may be timing pulleys, V pulleys, flat pulleys, chain wheels, etc., which are suitable for the types of the belt bodies 13, 14. Also,
The drive motors 1 and 2 are usually servo motors having good controllability, but a general electric motor, or a hydraulic motor in some cases, may be used.

3 to 5 show an embodiment of an injection molding machine according to the present invention. In these drawings, reference numeral B is a mold clamping device of the injection molding machine. The mold clamping device B movably supports a movable platen 27 having a mold 26 attached to four tie rods 24 integrally connecting a fixed platen 22 having a mold 21 attached thereto and an end plate 23. The torg mechanism 28 is provided between the movable plate 27 and the end plate 23, and the crosshead 3 of the torg mechanism 28 is provided.
0 is moved by a pair of left and right screw mechanisms 31 operated by the drive unit A to move and close the movable platen 27 in the mold.

The toggle mechanism 28 includes a pair of upper and lower toggle links 3 whose one end is connected to the end plate 23 by a pin 33.
4, a pair of upper and lower toggle links 37, one end of which is connected to the movable plate 27 by a pin 35 and the other end of which is connected to the other end of the toggle link 34 by a pin 36;
And a pair of upper and lower toggle links 40 connected to the toggle link 34 and the crosshead 30 at 39,
A left and right pair are provided. The screw mechanism 31 includes a pair of left and right ball screw shafts 42 rotatably supported by the end plate 23, and a pair of ball nuts 43 fixed to the cross head 30 and screwed to the ball screw shaft 42. . The pair of left and right ball screw shafts 42 are parallel to each other.

The end portions of the tie rods 24 on the end plate 23 side are respectively screw shafts 24a.
A chain wheel 45 having a nut structure is screwed onto each of the two. And four chain wheels 45,
The drive chain wheel 47 of the electric motor 46 such as a servomotor fixed to the end plate 23 is attached to the chain 4
8 is wound, and when each chain wheel 45 is rotated by the electric motor 46 via the drive chain wheel 47 and the chain 48, each chain wheel 45
Move back and forth in the axial direction of each tie rod 24 to move each tie rod 2 between the fixed platen 22 and the end plate 23.
The lengths of 4 are finely adjusted. The tension of the chain 48 is adjusted by a tension pulley 50 that is moved in the radial direction by operating a handle 49.

The crosshead 30 has a pair of left and right guide holes 30.
a, and those guide holes 30a are provided in the end plate 2
The pair of left and right guide rods 52 fixed to each other and parallel to each other are fitted to each other to move along the guide rods 52, 52.

The fixed platen 22, the end plate 23,
The structure and operation of the movable plate 27, the toggle mechanism 28, the screw mechanism 31, etc. are well known. Further, since the drive unit A is the drive unit shown in FIGS. 1 and 2 as described above except that the drive unit A is upside down, the same members and the like will be denoted by the same reference numerals and detailed description thereof will be omitted. Omit it. In this mold clamping device B, the rotary members 8 and 9 to be driven by the drive device A are the ball screw shafts 42 and 42 of the screw mechanism 31, and the support member 4 of the drive device A is the end plate 23. There is.

In the mold clamping device B having the above structure, when the drive motors 1 and 2 are operated, the pair of ball screw shafts 42 rotate in synchronization with each other, and the ball nuts 43,
The cross head 30 is moved along with the guide rods 52, 52 together with 43, and the movable platen 27 is moved through the toggle mechanism 28, as is well known, according to the rotation direction of the movable plate 27 for clamping or opening.

In the above, the pair of ball screw shafts 42
Rotate in exactly synchronization with each other, and the pair of ball nuts 43
Are accurately and synchronously moved, the toggle mechanism 28 operates smoothly to open and close the movable platen 27.

FIG. 6 shows another embodiment of the injection molding machine according to the present invention. In this figure, reference numeral C is an injection device of an injection molding machine. In the injection device C, a pusher plate 66 having an injection screw 65 rotatably attached to a plurality of guide rods 64 integrally connecting a front plate 62 to which a heating cylinder 61 is fixed and a rear plate 63 is movable. By supporting the pusher plate 66 and moving the pusher plate 66 forward together with the injection screw 65 by a pair of screw mechanisms 67 operated by the drive unit A, the molten resin is removed from the nozzle (not shown) of the heating cylinder 61. Type 2
1, 26 (see FIG. 3) are injected into the molding cavities.

The screw mechanism 67 includes a ball screw shaft 69 whose both ends are rotatably supported by the front plate 62 and the rear plate 63, and a ball nut 70 fixed to the pusher plate 66 and screwed to the ball screw shaft 69. It consists of and. Also in this case, the pair of ball screw shafts 69 are parallel to each other.

Also in this injection device C, the front plate 62, the rear plate 63, the pusher plate 66,
The structure and operation of the screw mechanism 67 and the like are well known. Further, since the driving device A is the driving device shown in FIGS. 1 and 2 as in the case of the mold clamping device B, the same members and the like are designated by the same reference numerals and detailed description thereof will be omitted. In the injection device C, the rotary members 8 and 9 to be driven by the drive device A are the ball screw shafts 69 of the screw mechanism 67, and the support member 4 of the drive device A is the rear plate 63.

In the injection device C configured as described above, when the drive motors 1 and 2 are operated, the pair of ball screw shafts 69 rotate in synchronization with each other, and the ball nuts 70,
The pusher plate 66 together with 70 is moved along the guide rods 64, 64 according to the rotation direction of the pusher plate 66.

Also in this case, the pair of ball screw shafts 69 are
Since the pair of ball nuts 70 are accurately synchronized with each other and the pair of ball nuts 70 are accurately synchronized with each other, the pusher plate 66 pushes the injection screw 6b5 and smoothly advances to inject the molten resin in the heating cylinder 61 into the molding cavity.

Screw mechanism 3 of the mold clamping device B and the injection device C shown in the figure.
Reference numerals 1 and 67 are for converting rotational movement into linear movement. Rotation of the ball screw shafts 42 and 69 causes the ball nut 4 to rotate.
Although 3, 70 move, the ball screw shaft may move by the rotation of the ball nut. In the case of the mold clamping device B and the injection device C of the injection molding machine, the drive motors 1 and 2 are usually servomotors, and the belt bodies 13 and 14 are timing belts. Drive device A
Can also be applied to, for example, an ejector device of an injection molding machine, a nozzle touch device that advances and retracts the injection device C with respect to the mold clamping device B, and the like.

[0034]

As described above, according to the present invention,
It is possible to provide a driving device and an injection molding machine that can accurately rotate a plurality of rotating members in synchronization with each other without separately providing a synchronizing device. Further, since it is not necessary to separately provide a synchronizing device, it is possible to provide a driving device and an injection molding machine which have a simple structure and are inexpensive.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a drive device according to the present invention.

2 is a side view of the drive device of FIG. 1. FIG.

FIG. 3 is a front view showing an embodiment of an injection molding machine according to the present invention.

4 is a side view of the injection molding machine of FIG.

5 is a front view of a crosshead of the injection molding machine of FIG.

FIG. 6 is a sectional view showing another embodiment of the injection molding machine according to the present invention.

FIG. 7 is a front view showing a drive device of a conventional injection molding machine.

FIG. 8 is a front view showing another drive device.

[Explanation of symbols]

1 and 2 drive motor 5 and 6 drive pulley 8 and 9 rotating member 10 and 11 driven pulley 13 and 14 belt body 27 movable plate 31 screw mechanism 42 and 69 ball screw shaft (rotating member) 43 and 70 ball nut 65 injection screw 66 Pusher plate A Drive device B Mold clamping device C Injection device

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16H ⁷ /00-7/24 F16H 19/00-37/16 B29C 45/00-45/84

Claims (6)

(57) [Claims] A plurality of drive motors each having a drive pulley are supported by a support member, and a plurality of rotating members each having a driven pulley are rotatably provided on the support member.
At the same time, the respective rotary members are synchronized with each other via the same number of belt bodies as the drive motors wound around the drive pulleys and the driven pulleys by the respective drive motors.
A driving device for rotating and, each belt member is respectively different one drive each other
A drive device which is wound around a drive pulley of a motor and a driven pulley of each of the rotating members . 2. The drive device according to claim 1, wherein each of the drive motor and the rotary member is two in number. 3. The drive device according to claim 1, wherein each drive motor is a servo motor. 4. A plurality of drive motors each having a drive pulley are supported by a supporting member, and a plurality of rotating members each having a driven pulley are rotatably provided on the supporting member.
At the same time, the respective rotary members are synchronized with each other via the same number of belt bodies as the drive motors wound around the drive pulleys and the driven pulleys by the respective drive motors.
An injection molding machine equipped with a drive device for rotating the same, wherein the drive device is the drive device according to any one of claims 1 to 3. 5. The injection molding machine according to claim 4, wherein the drive device is a drive device of a screw mechanism of a mold clamping device that moves the movable plate. 6. The injection molding machine according to claim 4, wherein the drive device is a drive device of a screw mechanism of an injection device that moves a pusher plate provided with an injection screw.