Injection molding machine

• US 20070054007A1
• Filed: 09/07/2006
• Published: 03/08/2007
• Est. Priority Date: 09/08/2005
• Status: Active Grant

• Current Assignee: Nissei Plastic Industrial Co., Ltd.
• Original Assignee: Nissei Plastic Industrial Co., Ltd.
• Inventors: Unno, Yoshimoto, Yamaura, Hiroshi
• Granted Patent: US 7,896,637 B2
• Time in Patent Office: Days
• US Class Current: 425/587
• CPC Class Codes: B29C 45/82 Hydraulic or pneumatic circuits

Abstract

When constructing an injection molding machine M that is equipped with hydraulic pumps 2, which control discharge flow rates by variably controlling the number of revolutions of a drive motor 3, and that drives hydraulic actuators 4a . . . by these hydraulic pumps 2; the injection molding machine M is equipped with a hydraulic drive member 6 having multiple hydraulic pumps 2p and 2q, and a hydraulic oil supply circuit 5 jointly or individually supplying hydraulic oil to be discharged from multiple hydraulic pumps 2p and 2q to a hydraulic actuator 4a, 4b, 4c, 4d or 4e selected from the multiple hydraulic actuators 4a . . . .

Claims

1. An injection molding machine, wherein, in an injection molding machine that is equipped with hydraulic pumps to control discharge flow rates by variably controlling the number of revolution of a drive motor, and that drives hydraulic actuators by the hydraulic pumps;

the injection molding machine is equipped with a hydraulic drive member having a plurality of hydraulic pumps and a hydraulic oil supply circuit, which jointly or individually supplies hydraulic oil discharged from the plurality of hydraulic pumps to a selected hydraulic actuator out of the multiple hydraulic actuators.

2. The injection molding machine according to claim 1, wherein, the hydraulic actuators include at least an injecting cylinder that moves a screw, which is internally contained in a heating cylinder of the injection unit, back and forth.

3. The injection molding machine according to claim 1 wherein the hydraulic actuators include at least a measuring motor that rotates a screw, which is internally contained in a heating cylinder of the injection unit.

4. The injection molding machine according to claim 1, wherein, the hydraulic actuators include at least a mold clamping cylinder, which opens/closes and clamps a mold in the injection unit.

5. The injection molding machine according to claim 1, wherein, the hydraulic actuators include at least an ejecting cylinder that ejects a molded article in a mold.

6. The injection molding machine according to claim 1, wherein, the hydraulic actuators include at least an injection unit moving cylinder, which moves the injection unit back and forth, and which attaches/detaches a nozzle to/from a mold.

7. The injection molding machine according to claim 1, wherein, the hydraulic pumps with the same rating are used for the multiple hydraulic pumps.

8. The injection molding machine according to claim 1, wherein, the hydraulic pumps with different ratings are used for the multiple hydraulic pumps.

9. The injection molding machine according to claim 1, wherein, the multiple hydraulic pumps are constructed as a pump unit integrated with a pump support base.

10. The injection molding machine according to claim 1, wherein, a variable discharge type hydraulic pump where multiple fixed discharge flow rates can be set according to the change of a swash plate angle is used for the hydraulic pumps.

11. The injection molding machine according to claim 1, wherein, a servomotor connected to a servo circuit is used for the drive motor.

12. The injection molding machine according to claim 1, wherein, the hydraulic oil supply circuit is equipped with a combining circuit that combines the hydraulic oil to be discharged from the multiple hydraulic pumps and supplies to the hydraulic actuators.

13. The injection molding machine according to claim 1, wherein, the hydraulic oil supply circuit is equipped with one or two or more switching valves that individually supply the hydraulic oil to be discharged from the multiple hydraulic pumps to the hydraulic actuators.

14. The injection molding machine according to claim 13, wherein, the switching valves have switching functions relating to the supply, stoppage and discharge of the hydraulic oil to each hydraulic actuator.