Hydroelectric hybrid injection molding machine

Abstract

The present invention is a hydroelectric hybrid injection molding machine including a machine base, a material barrel, a screw and a power system. The power system includes a power motor, an injection unit, a feed unit and a hydraulic auxiliary unit, the injection unit includes an injection power member, an injection transmission member and a first clutch, the feed unit includes a feed power member, a feed transmission member and a second clutch, the first and second clutches are spaced apart from each other on the output shaft, the hydraulic auxiliary unit includes an auxiliary cylinder and an accumulator, and during injection, the accumulator releases energy and the rodless cavity of the auxiliary cylinder is filled with oil. The hydroelectric hybrid injection molding machine of the present invention uses the same motor for injection and feed with the cooperation of the coaxial dual clutch, which can reduce the selection standard of the motor, while the use of the auxiliary cylinder ensures the pressure, speed and accuracy of the injection, especially during injection, and at the same time, the high-precision movement of the screw can be achieved by controlling the hydraulic pressure during post-release and back pressure operations.

Description

[Technical Field]

[0001] The present invention relates to the field of injection molding machines, and more particularly to an oil-electric hybrid injection molding machine. [Background technology]

[0002] A conventional all-electric injection molding machine has the following operating states: Injection: The injection motor drives the threaded rod to rotate, propelling the screw forward. Pressure Hold: The pressure in the mold cavity and barrel is maintained for a period of time, while the injection motor continues to work. Feed: The feed motor drives the screw to rotate (the screw can only rotate in one direction). When the feed motor drives the screw to rotate, the pressure in the front part of the screw becomes larger and larger, generating back pressure. At this time, the ball screw rod moves backward to release the back pressure. At this time, the feed motor and injection motor work simultaneously. Post-release (anti-cast): After the feeding operation is completed, the injection screw needs to retreat by a certain displacement to prevent the melt overflow.

[0003] However, in most injection molding machines, the injection shaft and feed shaft are each controlled by a single servo motor. The injection motor drives the rotation of the ball screw rod via the injection belt, propelling the screw forward and backward, and the feed motor drives the rotation of the screw during feeding. Thus, one servo motor is required for each of the injection and feed shafts (generally, the injection servo motor is larger than the feed servo motor). During the entire injection process, the two servo motors do not simultaneously exert maximum torque (i.e., when the injection motor's output power is at its maximum, the feed motor does not simultaneously exert maximum power, rather than vice versa), resulting in relatively low motor utilization efficiency. Therefore, the selection of a servo motor increases the cost of the injection molding machine, and low servo motor utilization results in high injection molding costs. Summary of the Invention [Problem to be solved by the invention]

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an improved hydroelectric hybrid injection molding machine. [Means for solving the problem]

[0005] In order to solve the above technical problems, the technical solutions adopted in the present invention are as follows: An oil-electric hybrid injection molding machine, Machine base and a material barrel including a cylinder body having a cavity formed therein and a nozzle provided at a tip of the cylinder body, the material barrel having a plastic raw material inlet provided in the cylinder body; a screw extending in the longitudinal direction of the material barrel and having a rear end exposed from the cylinder body; a power system for driving the screw to rotate about its axis and to move linearly along its length; In particular, the power system includes a power motor having an output shaft and a screw in parallel, an injection unit and a feed unit coaxially connected to the output shaft by a first clutch and a second clutch, respectively, and a hydraulic auxiliary unit; A first clutch and a second clutch are spaced apart from each other and are provided on the output shaft, and during injection, the injection unit drives the screw to move, the accumulator releases energy, and the rodless cavity of the auxiliary cylinder is filled with oil.

[0006] Preferably, the injection unit includes an injection power member capable of driving the screw to move in its longitudinal direction, an injection transmission member drivingly connecting the injection power member to an output shaft, and a first clutch provided on the output shaft and capable of connecting or disconnecting the output shaft and the injection transmission member relative to each other, while the feed unit includes a feed power member drivingly connected to the output shaft and capable of driving the screw to rotate, a feed transmission member drivingly connecting the feed power member to the output shaft, and a second clutch provided on the output shaft and capable of connecting or disconnecting the output shaft and the feed transmission member relative to each other. In this way, one power motor can be shared to perform the injection or feed process.

[0007] Preferably, the feed power member and the injection power member are arranged coaxially with the screw, and the feed power member and the injection power member are arranged to be rotatable relative to each other. In this way, by switching the corresponding clutch states of the first and second clutches, only one power motor (servo motor) is operated to perform screw injection molding. In particular, during injection molding, the maximum injection pressure is simultaneously supplied with energy by the servo motor and the auxiliary cylinder, so the servo motor specification is smaller than that of an injection shaft servo motor for all-electric injection molding, which not only reduces the cost of selecting the motor specification but also reduces the injection molding cost.

[0008] According to one specific embodiment and preferred aspect of the present invention, the machine base is formed with an injection head plate, an injection in-process plate, and an injection tail plate, the material barrel and the injection head plate are fixed, the injection in-process plate is slidably mounted on the machine base as the screw moves along its longitudinal direction, the power motor, the injection unit, and the feed unit are mounted on the injection in-process plate, and the auxiliary cylinder is mounted between the injection in-process plate and the injection tail plate. The installation of these three plates realizes the installation of a power system with a compact structure, small volume, and easy implementation. At the same time, the assistance of the auxiliary cylinder further facilitates injection and processing, and can speed up the screw injection speed, especially during injection, at the moment of accumulator release.

[0009] Preferably, the feed power member includes a feed transmission shaft coaxial with the screw and fixedly connected to the rear end of the screw, and a feed pulley fixed to the feed transmission shaft, and the feed transmission member includes a feed drive wheel connected to the output shaft via a second clutch, and a feed transmission belt for drivingly connecting the feed pulley and the feed drive wheel. The synchronization of the feed pulley and the screw facilitates precise control of the screw state during feeding.

[0010] Furthermore, the injection power member includes an injection transmission shaft coaxially rotatably connected to the feed transmission shaft, an injection pulley fixed to the injection transmission shaft, and a drive screw fixedly connected to the injection transmission shaft, the injection transmission shaft passing through the injection plate and rotatably disposed relative to the injection plate, the drive screw connected to the injection tail plate via the fixed plate, the injection transmission member includes an injection drive wheel connected to the output shaft via the first clutch, and an injection transmission belt for drivingly connecting the injection drive wheel and the injection pulley. The coaxial connection between the feed transmission shaft, the injection transmission shaft, and the screw realizes relative rotation between the feed power member and the injection power member.

[0011] According to another specific embodiment and preferred aspect of the present invention, the injection unit further includes an encoder located inside the injection transmission belt and synchronized with the injection pulley and / or the injection transmission belt, and a pressure sensor installed between the fixed plate and the injection tail plate. The installation of the encoder allows for precise control of the screw movement to control injection accuracy.

[0012] Specifically, the pressure sensor mainly obtains the feedback of the pressure of the screw during injection, and adjusts the injection process accordingly according to the feedback value.

[0013] In this example, the feed process is Feed (1): The servo motor rotates counterclockwise. In this case, the first clutch (dog clutch) is disengaged, and the second clutch (one-way clutch) works in a reverse direction, driving the screw to rotate in place and feed. As the feed operation continues, more and more material accumulates at the tip of the screw, the generated pressure becomes larger and larger, and the pressure sensed by this pressure sensor also becomes larger and larger. Feed (2): When the pressure sensed by the pressure sensor is greater than the set value, the rodless cavity of the auxiliary cylinder will be oil unloaded by the proportional throttle valve, reducing the screw retraction pressure. At this time, the auxiliary cylinder will retract, the ball screw rod will be driven to rotate counterclockwise, and the screw will retract. When the pressure sensed by the pressure sensor is less than the set value, the proportional throttle valve will reduce the oil unloading amount. Feed (1) and Feed (2) will be repeated until the screw reaches the next starting injection position, and the feed operation will be completed.

[0014] Preferably, there are two auxiliary cylinders, located on opposite sides of the screw centerline. The synchronous movement of the dual auxiliary cylinders with the impulse provided by the accumulator ensures the speed and stability of the injection.

[0015] The machine base includes an injection table and a support column located on the injection table. The injection table is rectangular with four support columns, which are located at the four corners of the injection table. The power system is connected to the support columns via two injection levers extending in the longitudinal direction of the screw.

[0016] Specifically, the two ejection levers pass through two support posts on the same side, and the ejection head plate, ejection tail plate, and ejection in progress plate are located between the two ejection levers. Each ejection lever passes through the corresponding ejection head plate, ejection in progress plate, and ejection tail plate in turn. The ejection in progress plate is slidably mounted on the ejection lever, and the distance between the ejection head plate and the ejection tail plate is constant and is directly positioned on the ejection lever.

[0017] In this example, to adjust the injection position (i.e., the distance between the nozzle and the mold), a first rod sleeve is formed at one end of each injection lever, and a second rod sleeve is formed at the injection lever between the two supports on the same side, and a regulator is formed to drive the injection lever to move along its own longitudinal direction.

[0018] In this example, the regulator is a telescopic rod connected to the other end of the injection lever and aligned with the extension direction of the injection lever. Specifically, the telescopic rod is an injection base cylinder. By driving the injection base cylinder, the first rod sleeve and the second rod sleeve are passed through the set positions, and the injection position is adjusted until both sides of the injection tail plate are attached between the tail support and the first rod sleeve, and both sides of the second rod sleeve are attached between the head column and the injection head plate.

[0019] The specific injection process is as follows: Injection: The servo motor and accumulator work together to drive the ball screw rod to rotate clockwise, propelling the plate and screw forward during injection, while the feed belt is held stationary by a one-way bearing (preventing the screw from rotating). Pressure Maintenance: Both the servo motor and the accumulator work together to maintain a constant pressure. feed: (1) The servo motor rotates counterclockwise. In this case, the dog clutch is disengaged and the one-way clutch works by blocking the feed, driving the screw to rotate in place and feed. As the feed operation continues, more and more material accumulates at the tip of the screw, the generated pressure becomes larger and larger, and the pressure sensed by this pressure sensor also becomes larger and larger. (2) When the pressure sensed by the pressure sensor is greater than the set value, the rodless cavity of the injection auxiliary cylinder will be oil unloaded by the proportional throttle valve, reducing the screw retraction pressure. At this time, the cylinder rod will retract, the ball screw rod will be driven to rotate counterclockwise, and the screw will retract. When the pressure sensed by the pressure sensor is less than the set value, the proportional throttle valve will reduce the oil unloading amount, and feed (1) and feed (2) will be repeated until the screw reaches the next starting injection position, completing the feed operation. Post-release (anti-cast): The dog clutch and one-way clutch are both in the disengaged state, the servo motor is not operating, the rod cavity of the injection assist cylinder is filled with oil through the oil passage of the hydraulic servo system, the ball screw rod rotates counterclockwise, and the screw (does not rotate) and the injection plate retract linearly.

[0020] According to another specific embodiment and preferred aspect of the present invention, the machine base is formed with an injection head plate and an injection tail plate, the material barrel and the injection head plate are fixed, the injection tail plate is slidably mounted on the machine base as the screw moves along its longitudinal direction, the power motor and the feed unit are mounted on the injection tail plate, and the injection unit and the auxiliary cylinder are mounted between the injection head plate and the injection tail plate. The installation of these two plates realizes the installation of a power system, has a compact structure, small volume, and is easy to implement, and at the same time, with the assistance of the auxiliary cylinder, further facilitates injection and processing, and can speed up the screw injection speed, especially during injection, at the moment of accumulator release.

[0021] Preferably, the feed power member includes a feed transmission shaft coaxial with the screw and fixedly connected to the rear end of the screw, and a feed pulley fixed to the feed transmission shaft, the feed transmission member includes a feed drive wheel connected to the output shaft via a second clutch, and a feed transmission belt for drive-connecting the feed pulley and the feed drive wheel, and the feed transmission shaft traverses the injection tail plate and is rotatably mounted on the injection tail plate via a bearing.

[0022] Furthermore, the injection power member includes two sets of drive screws whose centerlines are parallel to the centerline of the screw and which are provided corresponding to opposite sides of the screw, and an injection pulley provided on the end of the threaded rod of each set of drive screws which passes through the injection tail plate, and the injection transmission member includes an injection drive wheel connected to the output shaft via a first clutch, and an injection transmission belt for drivingly connecting the injection drive wheel and the two injection pulleys.In this way, even though the feed drive wheel and the injection drive wheel are installed relatively independently, since the injection drive wheel and the feed drive wheel are coaxial, it is possible to perform the injection and feed operations by operating a single power motor.

[0023] In this example, the two ejection pulleys and the ejection drive wheels are arranged in a triangular configuration, with the ejection drive wheels located inside the feed drive wheels and the two ejection pulleys located between the feed pulleys and the ejection tail plate, making the distribution space more reasonable.

[0024] Preferably, the injection unit further includes an encoder located inside the injection transmission belt and aligned with the injection pulley and / or the injection transmission belt, and a pressure sensor fixedly mounted on the injection tail plate and passing through the feed transmission shaft.

[0025] Specifically, there are two auxiliary cylinders, which are aligned vertically with the drive screw. The accumulator provides instantaneous force, and the synchronized movement of the dual auxiliary cylinders ensures the speed and stability of injection.

[0026] Furthermore, in order to adjust the injection position (i.e., the distance between the nozzle and the mold), in this example, a real guide rail is provided below the drive screw, and the injection head plate and injection tail plate are slidably mounted on the real guide rail from the bottom, and the same injection base cylinder as above is provided above each real guide rail, and position adjustment is achieved by driving the injection base cylinder.

[0027] At the same time, the first clutch is a dog clutch and the second clutch is a one-way clutch, which can be directly purchased on the market, and the principle thereof is not described here, but is clear and feasible.

[0028] The specific injection process is as follows: Injection: The servo motor and accumulator work together to drive the ball screw rod to rotate clockwise, propelling the injection tail plate and screw forward. At this time, the feed belt is prevented from moving by the one-way bearing (preventing the screw from rotating). Pressure Maintenance: Both the servo motor and the accumulator work together to maintain a constant pressure. feed: (1) The servo motor rotates counterclockwise. In this case, the dog clutch is disengaged and the one-way clutch works as a stop, driving the screw to rotate in place and feed. As the feed operation continues, more and more material accumulates at the tip of the screw, the generated pressure becomes larger and larger, and the pressure sensed by this pressure sensor also becomes larger and larger. (2) When the pressure sensed by the pressure sensor is greater than the set value, the rodless cavity of the injection auxiliary cylinder will be oil unloaded by the proportional throttle valve, reducing the screw retraction pressure. At this time, the cylinder rod will retract, the ball screw rod will be driven to rotate counterclockwise, and the screw will retract. When the pressure sensed by the pressure sensor is less than the set value, the proportional throttle valve will reduce the oil unloading amount, and feed (1) and feed (2) will be repeated until the screw reaches the next starting injection position, completing the feed operation. Post-release (anti-cast): The dog clutch and one-way clutch are both in the disengaged state, the servo motor is not operating, the rod cavity of the injection assist cylinder is filled with oil through the oil passage of the hydraulic servo system, the ball screw rod rotates counterclockwise, and the screw (does not rotate) and the injection tail plate retreat linearly.

[0029] By implementing the above technical solutions, the present invention has the following advantages over the prior art: With the cooperation of a coaxially arranged dual clutch, the present invention uses the same motor for injection and feed, which reduces the motor selection specifications, while the use of an auxiliary cylinder ensures the injection pressure, speed, and accuracy, especially during injection, in a hydroelectric hybrid system, and in the case of post-release and back pressure operations, high-precision screw movement can be achieved through hydraulic control, resulting in a simple structure and easy implementation. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of a hydroelectric hybrid three-platen injection molding machine according to a first embodiment. [Figure 2] FIG. 2 is a schematic front view of FIG. 1. [Figure 3] FIG. 2 is a schematic left view of FIG. 1. [Figure 4] FIG. 2 is a schematic plan view of FIG. [Figure 5] FIG. 5 is a schematic view taken along the arrow AA in FIG. 4. [Figure 6] FIG. 10 is a schematic diagram illustrating the configuration of a hydroelectric hybrid two-platen injection molding machine according to a second embodiment. [Figure 7] FIG. 7 is a front view of FIG. 6. [Figure 8] FIG. 7 is a schematic diagram of the right side of FIG. 6. [Figure 9] FIG. 7 is a schematic plan view of FIG. [Figure 10] FIG. 10 is a schematic view taken along the arrow BB in FIG. 9. DETAILED DESCRIPTION OF THE INVENTION

[0031] <Embodiment 1> As shown in FIG. 1, the hydroelectric hybrid three-platen injection molding machine of this embodiment includes a machine base 1, a material barrel 2, a screw 3, and a power system 4.

[0032] Specifically, the machine base 1 includes an injection table 10 and a support column 11 located on the injection table 10. The injection table 10 is rectangular, and there are four support columns 11, which are distributed corresponding to the four corners of the injection table 10. The power system 4 is connected to the support columns 11 via two injection levers 5 extending in the longitudinal direction of the screw 3.

[0033] In this embodiment, the two ejection levers 5 pass through two support columns 11 located on the same side.

[0034] The material barrel 2 includes a cylinder body 20 having a cavity formed therein and a nozzle 21 provided at the tip of the cylinder body 20, and the cylinder body 20 is provided with a plastic raw material inlet 20a.

[0035] The screw 3 extends in the longitudinal direction of the material barrel 2, and its rear end is exposed from the cylinder body 20.

[0036] The power system 4 is mainly used to drive the screw 3 so that it rotates around its own axis and moves linearly in its own longitudinal direction.

[0037] As shown in FIG. 2, the injection lever 5 is formed, from front to rear, with an injection head plate 6, an injection middle plate 7, and an injection tail plate 8. The cylinder body 20 is fixed to the injection head plate 6 from its rear end, and the injection head plate 6 and the injection tail plate 8 are fixed relative to each other and mounted on the injection lever 5. The injection middle plate 7 is located between the injection head plate 6 and the injection tail plate 8 and is slidably mounted on the injection lever 5.

[0038] The power system 4 includes a power motor 40 whose output shaft 400 is parallel to the screw 3 , an injection unit 41 , a feed unit 42 , and a hydraulic auxiliary unit 43 .

[0039] As shown in FIG. 3, the power motor 40, the injection unit 41, and the feed unit 42 are provided on the injection plate 7, and the hydraulic auxiliary unit 43 is provided between the injection plate 7 and the injection tail plate 8.

[0040] Specifically, the power motor 40 is a commonly used servo motor, and is fixed to the injection plate 7 via a stand, and the output shaft 400 is located between the injection head plate 6 and the injection plate 7, and is located at the top of the injection plate 7.

[0041] As shown in FIGS. 4 and 5, the injection unit 41 includes an injection power member 410 that can propel the screw 3 to move in its longitudinal direction, an injection transmission member 411 that drive-connects the injection power member 410 and the output shaft 400, and a first clutch 412 that is provided on the output shaft 400 and can relatively connect and disconnect the output shaft 400 and the injection transmission member 411.

[0042] The feed unit 42 includes a feed power member 420 that is drive-connected to the output shaft 400 and can drive the screw 3 to rotate, a feed transmission member 421 that drive-connects the feed power member 420 and the output shaft 400, and a second clutch 422 that is provided on the output shaft 400 and can relatively connect and disconnect the output shaft 400 and the feed transmission member 421.

[0043] The hydraulic auxiliary unit 43 includes an auxiliary cylinder 430 provided in parallel with the screw 3 , and the auxiliary cylinder 430 is provided between the injection plate 7 and the injection tail plate 8 .

[0044] In this embodiment, the injection power member 410 and the feed power member 420 share one power motor 40, and the first clutch 412 and the second clutch 422 are provided on the output shaft 400 at an interval.

[0045] Specifically, the feed power member 420 includes a feed transmission shaft a that is coaxial with the screw 3 and is provided at the rear end of the screw 3, and a feed pulley b that is fixed on the feed transmission shaft a. The feed transmission member 421 includes a feed drive wheel c that is connected to the output shaft 400 via a second clutch 422, and a feed transmission belt d that drives and connects the feed pulley b and the feed drive wheel c. The synchronization of the feed pulley and the screw facilitates precise control of the screw state during feeding.

[0046] The injection power member 410 includes an injection transmission shaft e that is coaxial with and drive-connected to the feed transmission shaft a, an injection pulley f that is fixed to the injection transmission shaft e, and a drive screw g that is fixedly connected to the injection transmission shaft e, the injection transmission shaft e passing through the injection plate 7 and being rotatable relative to the injection plate 7, and the drive screw g that is connected to the injection tail plate 8 by a fixed plate h.

[0047] The injection transmission member 411 includes an injection drive wheel i connected to the output shaft 400 via a first clutch 412, and an injection transmission belt j that drive-connects the injection drive wheel i and the injection pulley f.

[0048] Therefore, the coaxial connection between the feed transmission shaft a, the injection transmission shaft e, and the screw 3 allows the feed pulley b and the injection pulley f to rotate relative to each other.

[0049] The injection unit 41 further includes an encoder 413 located inside the injection transmission belt j and capable of moving synchronously with the injection pulley f, and a pressure sensor 414 provided between the fixed plate h and the injection tail plate 8.

[0050] Specifically, the injection pulley f, the injection drive wheel i, and the encoder 413 are gears, the injection transmission belt j is a toothed belt, and the encoder 413 and the injection pulley f are meshed together. In this way, the installation of the encoder 413 allows the movement of the screw 3 to be precisely controlled to control the injection accuracy.

[0051] Specifically, the pressure sensor mainly obtains the feedback of the pressure of the screw during injection, and adjusts the injection process accordingly according to the feedback value.

[0052] Specifically, the feed process is as follows: Feed (1): The servo motor rotates counterclockwise. In this case, the first clutch (dog clutch) is disengaged, and the second clutch (one-way clutch) works in a reverse direction, driving the screw to rotate in place and feed. As the feed operation continues, more and more material accumulates at the tip of the screw, the generated pressure becomes larger and larger, and the pressure sensed by this pressure sensor also becomes larger and larger. Feed (2): When the pressure sensed by the pressure sensor is greater than the set value, the rodless cavity of the auxiliary cylinder will be oil unloaded by the proportional throttle valve, reducing the screw retraction pressure. At this time, the auxiliary cylinder will retract, the ball screw rod will be driven to rotate counterclockwise, and the screw will retract. When the pressure sensed by the pressure sensor is less than the set value, the proportional throttle valve will reduce the oil unloading amount. Feed (1) and Feed (2) will be repeated until the screw reaches the next starting injection position, and the feed operation will be completed.

[0053] The hydraulic auxiliary unit 43 further includes an accumulator 431 connected to the oil passage of the auxiliary cylinder 430. During injection, the accumulator 431 releases energy, filling the rodless cavity of the auxiliary cylinder 430 with oil. The instantaneous force provided by the accumulator ensures the synchronous movement of the dual auxiliary cylinders, ensuring the speed of injection.

[0054] Therefore, by switching the corresponding clutch states of the first clutch 412 and the second clutch 422, only one power motor 40 (servo motor) needs to be operated to perform injection molding of the screw 3. In particular, during injection molding, the maximum injection pressure is simultaneously supplied with energy by the servo motor and the auxiliary cylinder 430, so the servo motor specifications are smaller than those of injection shaft servo motors used in all-electric injection molding, which not only reduces the cost of selecting motor specifications but also reduces the cost of injection molding.

[0055] At the same time, in order to adjust the distance between the nozzle and the mold, a first rod sleeve t1 is formed at one end of each injection lever 5, and a second rod sleeve t2 is formed on the injection lever 5 between the two supports on the same side, and a regulator t3 is formed to drive the injection lever 5 to move along its own longitudinal direction.

[0056] In this embodiment, the regulator t3 is an extendable rod that is connected to the other end of the ejection lever 5 and that extends in the same direction as the ejection lever 5.

[0057] Specifically, the telescopic rod is the injection base cylinder t30, and by driving the injection base cylinder t30, the first rod sleeve t1 and the second rod sleeve t2 are passed through the set positions, and the injection position is adjusted until both sides of the injection tail plate 8 are attached between the tail support 11 and the first rod sleeve t1, and both sides of the second rod sleeve t2 are attached between the head column 11 and the injection head plate 6.

[0058] Furthermore, the first clutch 412 is a dog clutch, and the second clutch 422 is a one-way clutch, which can be purchased directly on the market. Specifically, as a one-way clutch, one-way is also called a one-way clutch, which means that it can only transmit in one direction. When the power source drives the passive element, it only drives in one direction, and when the power source changes direction (for example, from clockwise to counterclockwise), the transmission function of the passive element stops.

[0059] Dog clutch: Consists of half clutches with dogs on the end faces. Half clutch I is fixed to the drive shaft, and half clutch II is connected to the driven shaft using a guide flat key (or spline). The operating mechanism moves the slide block in the axial direction, thereby performing the clutch action.

[0060] In short, the injection molding process in the injection molding machine of this embodiment is as follows. Injection: The servo motor and accumulator work together, the dog clutch is engaged, and the one-way clutch is disengaged. At this time, the injection pulley drives the ball screw rod to rotate clockwise, propelling the plate and screw forward during injection. At this time, the feed belt is prevented from moving by the one-way bearing (preventing the screw from rotating). Pressure Maintenance: Both the servo motor and the accumulator work together to maintain a constant pressure. Feed (divided into the following steps): (1) The servo motor rotates counterclockwise. In this state, the dog clutch is disengaged and the one-way clutch works by blocking, and the feed pulley drives the screw to rotate in place and feed. As the feed operation continues, more and more material accumulates at the tip of the screw, generating more and more pressure, and the pressure sensed by the pressure sensor also increases. (2) When the pressure sensed by the pressure sensor is greater than the set value, the rodless cavity of the auxiliary cylinder is oil-unloaded by the proportional throttle valve, reducing the screw retraction pressure. At this time, the auxiliary cylinder retracts, driving the ball screw rod to rotate counterclockwise, and the screw retracts. When the pressure sensed by the pressure sensor is less than the set value, the proportional throttle valve reduces the oil unloading amount. Feed (1) and feed (2) are repeated until the screw reaches the next starting injection position, completing the feed operation. Post-release (anti-cast): The dog clutch and one-way clutch are both in the disengaged state, the servo motor is not operating, the rod cavity of the injection assist cylinder is filled with oil through the oil passage of the hydraulic servo system, the ball screw rod rotates counterclockwise, and the screw (not rotating) and injection plate retract linearly.

[0061] <Embodiment 2> As shown in FIG. 5, the basic structure and operation principle of the hydroelectric hybrid two-platen injection molding machine of this embodiment are the same as those of embodiment 1, but the difference is that this embodiment only has an injection head plate 6 and an injection tail plate 8, and the embodiment of the power system 4 also has differences.

[0062] As shown in Figure 6, the cylinder body 20 is fixed to the injection head plate 6 from its rear end, and the injection tail plate 8 is slidably mounted on the machine base 1 as the screw 3 moves along its longitudinal direction. The power motor 40 and feed unit 42 are mounted on the injection tail plate 8, and the injection unit 41 and auxiliary cylinder 430 are mounted on the injection head plate 6 and injection tail plate 8. The two-plate installation realizes the installation of a power system with a compact structure, small volume, and easy implementation. At the same time, the assistance of the auxiliary cylinder further facilitates injection and processing, and can speed up the screw injection speed, especially at the moment of accumulator release during injection.

[0063] 7, the feed power member 420 includes a feed transmission shaft a that is coaxial with the screw 3 and is provided at the rear end of the screw 3, and a feed pulley b that is fixed on the feed transmission shaft a. The feed transmission member 421 includes a feed drive wheel c that is connected to the output shaft 400 via a second clutch 422, and a feed transmission belt d that drives and connects the feed pulley b and the feed drive wheel c. The synchronization of the feed pulley and the screw facilitates precise control of the screw state during feeding.

[0064] The injection power member 410 has a center line parallel to that of the screw 3 and includes two sets of drive screws g provided on opposite sides of the screw 3, and an injection pulley f provided on the end of the threaded rod through which the injection tail plate 8 of each set of drive screws g passes. The injection transmission member 411 includes an injection drive wheel i connected to the output shaft 400 via a first clutch 412, and an injection transmission belt j for drivingly connecting the injection drive wheel i and the two injection pulleys f. In this way, even though the feed drive wheel and the injection drive wheel are installed relatively independently, the injection drive wheel and the feed drive wheel are coaxial, so that injection and feed operations can be performed by operating a single power motor.

[0065] For assembly of the injection pulley f, the end of the drive screw g is fixedly connected to the injection transmission shaft e, and the injection pulley f is fixed to the injection transmission shaft e.

[0066] As shown in Figure 8, the two injection pulleys f and the injection drive wheel i are arranged in a triangular configuration, with the injection drive wheel i located inside the feed drive wheel c, and the two injection pulleys f located between the feed pulley b and the injection tail plate 8.

[0067] As shown in Figures 9 and 10, the injection unit 41 further includes an encoder 413 located inside the injection transmission belt j and capable of moving synchronously with the injection pulley f, and a pressure sensor 414 fixedly provided on the injection tail plate 8 and passing through the feed transmission shaft a.

[0068] In this embodiment, the injection pulley f, the injection drive wheel i, and the encoder 413 are gears, the injection transmission belt j is a toothed belt, and the encoder 413 and the injection pulley f are meshed together. In this way, the installation of the encoder 413 allows the movement of the screw 3 to be precisely controlled to control the injection accuracy.

[0069] Specifically, there are two auxiliary cylinders 430, which are aligned vertically with the drive screw g, and the auxiliary cylinders 430 and the accumulator 431 are fixed to the injection head plate 6, and the drive screw is a commonly used ball screw structure.

[0070] Furthermore, in order to adjust the injection position (i.e., the distance between the nozzle and the mold), in this embodiment, a real guide rail x is provided below the drive screw g, and the injection head plate 6 and the injection tail plate 8 are provided slidably on the real guide rail x from the bottom, and above each of the real guide rails x, an identical injection base cylinder t30 is provided correspondingly, and position adjustment is achieved by driving the injection base cylinder t30.

[0071] At the same time, the injection molding process of this embodiment is as follows: Injection: The servo motor and accumulator work together, the dog clutch is engaged, and the one-way clutch is disengaged. At this time, the injection pulley drives the ball screw rod to rotate clockwise, propelling the injection tail plate and screw forward. At this time, the feed belt is prevented from moving by the one-way bearing (preventing the screw from rotating). Pressure Maintenance: Both the servo motor and the accumulator work together to maintain a constant pressure. Feed: (1) The servo motor rotates counterclockwise. In this state, the dog clutch is disengaged and the one-way clutch works as a stop, driving the screw to rotate in place and feed. As the feed operation continues, more and more material accumulates at the tip of the screw, generating more and more pressure, and the pressure sensed by the pressure sensor also increases. (2) When the pressure sensed by the pressure sensor is greater than the set value, the rodless cavity of the auxiliary injection cylinder will use the proportional throttle valve to unload oil, reducing the screw retraction pressure. At this time, the cylinder rod will retract, driving the ball screw rod to rotate counterclockwise, causing the screw to retract. When the pressure sensed by the pressure sensor is less than the set value, the proportional throttle valve will reduce the amount of oil unloaded. Feed (1) and feed (2) will be repeated until the screw reaches the next starting injection position, completing the feed operation. Post-release (anti-cast): The dog clutch and one-way clutch are both in the disengaged state, the servo motor is not operating, the rod cavity of the injection assist cylinder is filled with oil through the oil passage of the hydraulic servo system, the ball screw rod rotates counterclockwise, and the screw (does not rotate) and the injection tail plate retract linearly.

[0072] Therefore, the use of the injection molding machine of the above embodiment has the following advantages. 1. By using the same one-way clutch and dog clutch together, the same motor can be used for injection and feeding, which not only reduces the motor selection requirements but also reduces the cost of injection molding. 2. By using an auxiliary cylinder and accumulator, it is a hydroelectric hybrid formed by an auxiliary cylinder and a servo motor, which ensures the injection speed especially during injection, and at the same time, in the case of post-release and back pressure operations, the hydraulic control can realize high-precision movement of the screw, with a simple structure and easy implementation. 3. The installation of an encoder can record and accurately understand the screw position, meeting the needs of high-precision injection molding. At the same time, the feeding process can be divided into feed (1) and feed (2), ensuring that the injection molding pressure meets the needs of injection molding.

[0073] Although the embodiments of the present invention have been described in detail above, these are intended to enable those skilled in the art to understand and practice the contents of the present invention, and are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the concept of the present invention should be included in the scope of protection of the present invention. [Explanation of symbols]

[0074] 1: machine base, 10: injection table, 11: support, x: real guide rail, 2: material barrel, 20: cylinder body, 21: nozzle, 20a: plastic raw material inlet, 3: screw, 4: power system, 40: power motor (servo motor), 400: output shaft, 41: injection unit, 410: injection power member, e: injection transmission shaft, f: injection pulley, g: drive screw, h: fixed plate, 411: injection transmission member, i: injection drive wheel, j: injection transmission belt, 412: first clutch (first clutch), 413: encoder , 414: Pressure sensor, 42: Feed unit, 420: Feed power member, a: Feed transmission shaft, b: Feed pulley, 421: Feed transmission member, c: Feed drive wheel, d: Feed transmission belt, 422: Second clutch (one-way clutch), 43: Hydraulic auxiliary unit, 430: Auxiliary cylinder, 431: Accumulator, t1: First rod sleeve, t2: Second rod sleeve, t3: Regulator, t30: Injection base cylinder, 5: Injection lever, 6: Injection head plate, 7: Injection plate, 8: Injection tail plate.

Claims

1. Machine base and a material barrel including a cylinder body having a cavity formed therein and a nozzle provided at a tip of the cylinder body, the cylinder body having an inlet for a plastic raw material; a screw extending in the longitudinal direction of the material barrel and having a rear end exposed from the cylinder body; a power system that drives the screw to rotate about its axis and to move linearly along its longitudinal direction, the power system includes a power motor whose output shaft is parallel to the screw, an injection unit and a feed unit coaxially connected to the output shaft by a first clutch and a second clutch, respectively, and a hydraulic auxiliary unit, the hydraulic auxiliary unit including an auxiliary cylinder provided parallel to the screw and an accumulator communicating with an oil passage of the auxiliary cylinder; the first clutch and the second clutch are spaced apart from each other and are provided on the output shaft, and during injection, the injection unit drives the screw to move; the accumulator releases energy, and the rodless cavity of the auxiliary cylinder is filled with oil; the injection unit includes an injection power member capable of propelling the screw to move in its longitudinal direction, an injection transmission member that drive-connects the injection power member and the output shaft, and a first clutch that is provided on the output shaft and can relatively connect and disconnect the output shaft and the injection transmission member, the feed unit includes a feed power member that is drivingly connected to the output shaft and can drive the screw to rotate, a feed transmission member that drivingly connects the feed power member and the output shaft, and a second clutch that is provided on the output shaft and can relatively connect and disconnect the output shaft and the feed transmission member, an injection head plate, an injection in progress plate, and an injection tail plate are formed on the machine base, the material barrel and the injection head plate are fixed, the injection in progress plate is slidably mounted on the machine base as the screw moves along its longitudinal direction, the power motor, the injection unit, and the feed unit are mounted on the injection in progress plate, and the auxiliary cylinder is mounted between the injection in progress plate and the injection tail plate; the feed power member includes a feed transmission shaft coaxial with the screw and fixedly connected to a rear end of the screw, and a feed pulley fixed to the feed transmission shaft, the feed transmission member including a feed drive wheel connected to the output shaft via the second clutch, and a feed transmission belt for drive-connecting the feed pulley and the feed drive wheel, The injection power member includes an injection transmission shaft rotatably connected to the feed transmission shaft and an injection pulley fixed to the injection transmission shaft, and a drive screw fixedly connected to the injection transmission shaft, wherein the injection transmission shaft passes through the injection plate and is rotatable relative to the injection plate, and the drive screw is connected to an injection tail plate via a fixed plate; the injection transmission member includes an injection drive wheel connected to the output shaft via a first clutch, and an injection transmission belt for drivingly connecting the injection drive wheel and the injection pulley; the injection unit further includes: an encoder located inside the injection transmission belt and synchronized with the injection pulley and / or the injection transmission belt; and a pressure sensor provided between the fixed plate and the injection tail plate, for acquiring pressure of the screw during injection and adjusting the injection process according to the acquired pressure.

2. 2. The hydroelectric hybrid injection molding machine according to claim 1, wherein the auxiliary cylinders are two in number and are located on opposite sides of the center line of the screw.

3. 3. The hydroelectric hybrid injection molding machine according to claim 2, wherein the machine base includes an injection table and a support column located on the injection table, the injection table is rectangular with four support columns distributed corresponding to the four corners of the injection table, and the power system is bridged to the support columns via two injection levers extending in the longitudinal direction of the screw.

4. 4. The hydroelectric hybrid injection molding machine according to claim 3, wherein the two injection levers pass through the two support columns on the same side, the injection head plate, the injection tail plate, and the injection in progress plate are located between the two injection levers, and each of the injection levers crosses the injection head plate, the injection in progress plate, and the injection tail plate on the corresponding side in turn, the injection in progress plate is slidably mounted on the injection lever, and the distance between the injection head plate and the injection tail plate is constant and is directly positioned on the injection lever.

5. A first rod sleeve is formed at one end of each of the ejection levers, and a second rod sleeve is formed at the ejection lever between the two support columns on the same side, and a regulator is formed to drive the ejection lever so that it moves along its longitudinal direction; 5. The hydroelectric hybrid injection molding machine according to claim 4, wherein the regulator is an injection base cylinder connected to the other end of each of the injection levers.

6. 2. The hydroelectric hybrid injection molding machine according to claim 1, wherein the feed power member and the injection power member are arranged coaxially with the screw, and the feed power member and the injection power member are arranged to be rotatable relative to each other.

7. 2. The hydroelectric hybrid injection molding machine according to claim 1, wherein the first clutch is a dog clutch and the second clutch is a one-way clutch.

8. Machine base and a material barrel including a cylinder body having a cavity formed therein and a nozzle provided at a tip of the cylinder body, the cylinder body having an inlet for a plastic raw material; a screw extending in the longitudinal direction of the material barrel and having a rear end exposed from the cylinder body; a power system that drives the screw to rotate about its axis and to move linearly along its longitudinal direction, the power system includes a power motor whose output shaft is parallel to the screw, an injection unit and a feed unit coaxially connected to the output shaft by a first clutch and a second clutch, respectively, and a hydraulic auxiliary unit, the hydraulic auxiliary unit including an auxiliary cylinder provided parallel to the screw and an accumulator communicating with an oil passage of the auxiliary cylinder; the first clutch and the second clutch are spaced apart from each other and are provided on the output shaft, and during injection, the injection unit drives the screw to move; the accumulator releases energy, and the rodless cavity of the auxiliary cylinder is filled with oil; the injection unit includes an injection power member capable of propelling the screw to move in its longitudinal direction, an injection transmission member that drive-connects the injection power member and the output shaft, and a first clutch that is provided on the output shaft and can relatively connect and disconnect the output shaft and the injection transmission member, the feed unit includes a feed power member that is drivingly connected to the output shaft and can drive the screw to rotate, a feed transmission member that drivingly connects the feed power member and the output shaft, and a second clutch that is provided on the output shaft and can relatively connect and disconnect the output shaft and the feed transmission member, an injection head plate and an injection tail plate are formed on the machine base, the material barrel and the injection head plate are fixed, the injection tail plate is slidably mounted on the machine base as the screw moves along its longitudinal direction, the power motor and the feed unit are mounted on the injection tail plate, and the injection unit and the auxiliary cylinder are mounted on the injection head plate and the injection tail plate; the feed power member includes a feed transmission shaft coaxial with the screw and fixedly connected to a rear end of the screw, and a feed pulley fixed to the feed transmission shaft, the feed transmission member including a feed drive wheel connected to the output shaft via the second clutch, and a feed transmission belt for drive-connecting the feed pulley and the feed drive wheel, the feed transmission shaft is rotatably mounted on the injection tail plate via a bearing, across the injection tail plate; the injection power member includes two sets of drive screws whose center lines are parallel to the center line of the screw and which are provided corresponding to opposite sides of the screw, and an injection pulley provided on an end of a threaded rod of each set of drive screws which passes through the injection tail plate; and the injection transmission member includes an injection drive wheel connected to the output shaft via a first clutch, and an injection transmission belt for drive-connecting the injection drive wheel and the two injection pulleys.

9. 9. The hydroelectric hybrid injection molding machine according to claim 8, wherein the injection unit further includes an encoder located inside the injection transmission belt and synchronized with the injection pulley and / or the injection transmission belt, and a pressure sensor fixedly provided on the injection tail plate and passing through the feed transmission shaft.

10. 9. The hydroelectric hybrid injection molding machine according to claim 8, wherein the two injection pulleys and the injection drive wheel are arranged in a triangular configuration, the injection drive wheel is located inside the feed drive wheel, and the two injection pulleys are located between the feed pulley and the injection tail plate.

11. 11. The hydroelectric hybrid injection molding machine according to claim 10, wherein the auxiliary cylinders are two, and are aligned vertically with the drive screw, and the two auxiliary cylinders move synchronously to inject with the instantaneous force provided by the accumulator.

12. 9. The hydroelectric hybrid injection molding machine according to claim 8, wherein a real guide rail is provided below the drive screw, the injection head plate and the injection tail plate are slidably mounted on the real guide rail from the bottom, and an injection base cylinder is provided above each real guide rail, and position adjustment is achieved by driving the injection base cylinder.

13. 9. The hydroelectric hybrid injection molding machine according to claim 8, wherein the first clutch is a dog clutch and the second clutch is a one-way clutch.

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