A control device of an injection apparatus outputs a control command to a hydraulic pressure device to perform injection by supplying hydraulic fluid to the back of an injection piston 15 from an accumulator 25 and, at this time, to execute speed control for controlling the speed of the plunger by an opening degree of an injection control valve. Further, the control device outputs a control command to the hydraulic pressure device to perform boosting by opening a booster valve to supply hydraulic fluid to the back of the booster piston and pressurizing the hydraulic fluid behind the injection piston by the booster piston and, at this time, to execute pressure control for controlling the pressure of the molding material by an opening degree of the injection control valve. Further, the control device can start outputting a control command for pressure control after start of outputting a control command for opening the booster valve in transition from injection to boosting.

Provided is an injection molding machine (1) including a plasticizing unit (2), an injection unit (3), a communication path (5a) configured to communicate therebetween and having an opening (5b) on the plasticizing unit side which is located on an axis of the screw (21), and a backflow prevention mechanism part (6) configured to close and open the opening on the plasticizing unit side by advancing and retreating the screw (21) in the axial direction, wherein the backflow prevention mechanism part (6) includes a tapered wedge portion (61) having an inclined surface (61a), a driving portion (63) which moves the wedge portion in the forward and backward directions, and a pressing member which is pressed against the inclined surface (61a) by forward movement of the wedge portion and moves the screw toward the opening on the plasticizing unit side.

Provided is an injection molding machine (1) including a plasticizing unit (2), an injection unit (3), a communication path (5a) configured to communicate therebetween and having an opening (5b) on the plasticizing unit side which is located on an axis of the screw (21), and a backflow prevention mechanism part (6) configured to close and open the opening on the plasticizing unit side by advancing and retreating the screw (21) in the axial direction, wherein the backflow prevention mechanism part (6) includes a tapered wedge portion (61) having an inclined surface (61a), a driving portion (63) which moves the wedge portion in the forward and backward directions, and a pressing member which is pressed against the inclined surface (61a) by forward movement of the wedge portion and moves the screw toward the opening on the plasticizing unit side.

An injection device has an injection cylinder for driving a plunger, a gas pressure type accumulator which supplies hydraulic fluid to the injection cylinder, a hydraulic fluid supply device which supplies the hydraulic fluid to the accumulator, a pressure sensor for detecting the gas pressure of the accumulator, and a control device which controls the hydraulic fluid supply device so as to suspend the supply of the hydraulic fluid when detection value of the pressure sensor reaches a predetermined target gas pressure before injection in the state where the hydraulic fluid is supplied from the hydraulic fluid supply device to the accumulator in a molding cycle.

An injection device has an injection cylinder for driving a plunger, a gas pressure type accumulator which supplies hydraulic fluid to the injection cylinder, a hydraulic fluid supply device which supplies the hydraulic fluid to the accumulator, a pressure sensor for detecting the gas pressure of the accumulator, and a control device which controls the hydraulic fluid supply device so as to suspend the supply of the hydraulic fluid when detection value of the pressure sensor reaches a predetermined target gas pressure before injection in the state where the hydraulic fluid is supplied from the hydraulic fluid supply device to the accumulator in a molding cycle.

A hydraulic drive apparatus includes a first hydraulic pump, a drive motor connected to the first hydraulic pump, a hydraulic line system connecting the first hydraulic pump to the consumer, and a closed-loop control unit. The closed-loop control unit has a first switching element to change a displacement volume of the first hydraulic pump between a predetermined minimum value and a maximum value. A second hydraulic pump is connected to the drive motor, and the hydraulic line system connects the second hydraulic pump to a consumer and has a first branch line connected to the first hydraulic pump, a second branch line connected to a second hydraulic pump, and a main line. The two branch lines open into the main line, and the closed-loop control unit has a second switching element for changing a displacement volume of the second hydraulic pump between a predetermined minimum value and a maximum value.

A hydraulic drive apparatus includes a first hydraulic pump, a drive motor connected to the first hydraulic pump, a hydraulic line system connecting the first hydraulic pump to the consumer, and a closed-loop control unit. The closed-loop control unit has a first switching element to change a displacement volume of the first hydraulic pump between a predetermined minimum value and a maximum value. A second hydraulic pump is connected to the drive motor, and the hydraulic line system connects the second hydraulic pump to a consumer and has a first branch line connected to the first hydraulic pump, a second branch line connected to a second hydraulic pump, and a main line. The two branch lines open into the main line, and the closed-loop control unit has a second switching element for changing a displacement volume of the second hydraulic pump between a predetermined minimum value and a maximum value.

An injection molding apparatus comprising an injection machine, a manifold, a mold, a clamp plate, an actuator interconnected to a valve pin and an external actuator controller, the actuator controller comprising a controller housing adapted to control upstream flow of drive fluid from an upstream actuator drive chamber such that the rate of travel of the drive piston is selectively adjustable to a first rate of travel or velocity over a first course of travel from a gate closed position to a predetermined position of upstream travel and such that the rate of travel of the drive piston beyond the predetermined intermediate upstream position occurs at a second rate of travel or velocity that is higher than the first rate of travel or velocity.

An injection molding apparatus comprising an injection machine, a manifold, a mold, a clamp plate, an actuator interconnected to a valve pin and an external actuator controller, the actuator controller comprising a controller housing adapted to control upstream flow of drive fluid from an upstream actuator drive chamber such that the rate of travel of the drive piston is selectively adjustable to a first rate of travel or velocity over a first course of travel from a gate closed position to a predetermined position of upstream travel and such that the rate of travel of the drive piston beyond the predetermined intermediate upstream position occurs at a second rate of travel or velocity that is higher than the first rate of travel or velocity.

An injection molding apparatus including:

a valve pin driven by an actuator, the valve pin extending axially through at least a portion of the channel length of the fluid flow channel, the fluid flow channel including a throat, downstream flow of the injection fluid being restricted by a bulb portion of the pin, the valve pin having an intermediate position where downstream flow of injection fluid is unrestricted and a fully downstream position where downstream flow of injection fluid is stopped at both the gate and at the throat, wherein the actuator is driven by a valve assembly comprised of a spool mechanically driven by first and second actuators or solenoids that each separately engage the spool at opposing axial ends to effect movement of the spool back and forth between the drive fluid flow positions.