CN113601784A

CN113601784A - Asymmetric vibration injection method and system

Info

Publication number: CN113601784A
Application number: CN202110745144.XA
Authority: CN
Inventors: 赖燕根; 宋建; 覃昌壬; 余吕宏
Original assignee: South China University of Technology SCUT; Guangzhou Huaxinke Intelligent Manufacturing Technology Co Ltd
Current assignee: South China University of Technology SCUT; Guangzhou Huaxinke Intelligent Manufacturing Technology Co Ltd
Priority date: 2021-06-30
Filing date: 2021-06-30
Publication date: 2021-11-05
Anticipated expiration: 2041-06-30
Also published as: CN113601784B

Abstract

The invention relates to an asymmetric vibration injection method and a system, wherein a first driver is started to drive a screw rod to run in a charging barrel; plasticizing the material in the material cylinder into a melt by means of the conveying and plasticizing functions of the screw rod, and conveying the melt to the nozzle; finally, the output of the second driver is started and controlled by the electric control device. At this time, the screw rod is moved forward in the axial direction thereof by the second driver while being periodically reciprocated. Because the screw rod alternately goes through the acceleration stage and the deceleration stage in turn in any vibration period, and the working parameters of the acceleration stage are different from the working parameters of the deceleration stage, the screw rod can do reciprocating acceleration and deceleration movement in the axial direction on the basis of the original operation, so as to realize the differential asymmetric vibration control of the screw rod in the axial direction. Therefore, the asymmetric vibration injection method optimizes the extrusion molding processing process by utilizing the asymmetric vibration effect of the screw, and improves the processing efficiency and the product quality of the molded product.

Description

Asymmetric vibration injection method and system

Technical Field

The invention relates to the technical field of vibration injection, in particular to an asymmetric vibration injection method and system.

Background

The polymer injection molding is widely applied in modern industry due to the characteristics of simple processing, high production efficiency, higher dimensional precision of molded products and the like. The plasticizing injection device is one of the key parts of the injection molding equipment, and the performance of the plasticizing injection device directly affects the efficiency of injection molding and the quality of products.

In the traditional reciprocating screw type injection molding machine, a screw has plasticizing and injection functions, can perform rotary motion to finish conveying and plasticizing materials, and can perform reciprocating axial motion to perform injection molding. However, the screw moves axially during plasticization, and the melt has a large axial temperature difference, which affects the processing efficiency and molding quality of the product.

Disclosure of Invention

Therefore, there is a need for an asymmetric vibration injection method and system, which can realize the differential asymmetric vibration control of the screw in the axial direction, and improve the processing efficiency and product quality of the molded product.

An asymmetric vibratory injection method, comprising the steps of: heating the charging barrel to a preset temperature; starting a first driver to drive the screw to run in the barrel; putting a material into a charging barrel, plasticizing the material into a melt, and conveying the melt to a nozzle of the charging barrel; and starting and controlling the output of a second driver to enable the screw to perform forward injection motion in the axis direction of the screw and perform periodic reciprocating vibration, wherein the screw sequentially goes through an acceleration stage and a deceleration stage in any vibration period, and the operation parameters in the acceleration stage are controlled to be different from the operation parameters in the deceleration stage, and the operation parameters comprise at least one of an injection speed vibration change mode and an injection speed vibration change time.

In the asymmetric vibration injection method, the first driver is started to drive the screw to run in the charging barrel; secondly, plasticizing the material in the charging barrel into a melt by means of the conveying and plasticizing functions of the screw, and conveying the melt to a nozzle; finally, the output of the second driver is enabled and controlled. At this time, the screw rod is moved forward in the axial direction thereof by the second driver while being periodically reciprocated. Because the screw rod alternately goes through the acceleration stage and the deceleration stage in turn in any vibration period, and the operation parameters of the acceleration stage are different from the operation parameters of the deceleration stage, the screw rod can do reciprocating acceleration and deceleration movement in the axial direction on the basis of the original operation, so as to realize the differential asymmetric vibration control of the screw rod in the axial direction. Therefore, the asymmetric vibration injection method optimizes the extrusion molding process by utilizing the asymmetric vibration effect of the screw, realizes the accurate control of the axial vibration of the screw, and further improves the processing efficiency and the product quality of molded products.

In one embodiment, the operating parameter comprises an injection speed variation time, and the acceleration phase is accelerated from a first injection speed to a second injection speed for a first time t₁Less than a second time t taken for decelerating from the second injection speed to the first injection speed in the deceleration stage₂。

In one embodiment, the screw is accelerated from the first injection speed to the second injection speed at a first constant acceleration in the acceleration phase.

In one embodiment, in the deceleration phase, the screw is decelerated from the second injection speed to the first injection speed at a second constant acceleration, and the second constant acceleration is smaller than the first constant acceleration.

In one embodiment, the method further comprises: after the injection action is finished, applying a periodically-changed pressure to the screw along the axial direction of the screw so as to maintain the pressure of the product in the mold.

In one embodiment, the step of applying a periodically varying pressure to the screw in the direction of the axis of the screw comprises: in any pressure applying period, the pressure applied to the screw along the axial direction of the screw is increased from the first pressure to the second pressure, and the pressurizing time is controlled to be the third time t₃(ii) a After the pressurization, the pressure applied to the screw in the axial direction of the screw is reduced from the second pressure to the first pressure, and the decompression time is controlled to be a fourth time t₄And the third time t₃Less than the fourth time t₄。

In one embodiment, the step of enabling and controlling the output of the second driver comprises: starting a hydraulic pump and the second driver; and opening a solenoid directional valve, and controlling the hydraulic pump to periodically supply oil to the second driver.

An asymmetric vibratory injection system employing the asymmetric vibratory injection method of any of the above, the asymmetric vibratory injection system comprising: a slide base; the charging barrel is internally provided with a material cavity, and a feeding hole and a nozzle which are communicated with the material cavity are arranged on the charging barrel; the injection component is arranged on the sliding seat in a sliding manner and comprises a first driver, a screw rod and a heater, the heater is arranged on the material barrel, at least one part of the screw rod extends into the material cavity, and the first driver is in driving connection with the screw rod so as to drive the screw rod to run; the second driver is in driving connection with the screw rod so as to drive the screw rod to move along the axial direction of the screw rod and simultaneously perform periodic reciprocating vibration; and the electric control device is in control coordination with the second driver so as to control the asymmetric periodic output of the second driver.

The asymmetric vibration injection system adopts the above asymmetric vibration injection method, and the first driver is started to drive the screw to run in the charging barrel; secondly, plasticizing the material in the charging barrel into a melt by means of the conveying and plasticizing functions of the screw, and conveying the melt to a nozzle; finally, the output of the second driver is started and controlled by the electric control device. At this time, the screw rod is moved forward in the axial direction thereof by the second driver while being periodically reciprocated. Because the screw rod alternately goes through the acceleration stage and the deceleration stage in turn in any vibration period, and the operation parameters of the acceleration stage are different from the operation parameters of the deceleration stage, the screw rod can do reciprocating acceleration and deceleration movement in the axial direction on the basis of the original operation, so as to realize the differential asymmetric vibration control of the screw rod in the axial direction. Therefore, the asymmetric vibration injection method optimizes the extrusion molding process by utilizing the asymmetric vibration effect of the screw, realizes the accurate control of the axial vibration of the screw, and further improves the processing efficiency and the product quality of molded products.

In one embodiment, the injection component further comprises a coupling, and the output shaft of the first driver is in driving connection with the screw through the coupling.

In one embodiment, the electric control device comprises a hydraulic pump, an electromagnetic directional valve and a controller, the hydraulic pump and the electromagnetic directional valve are both electrically connected with the controller, and the hydraulic pump is in control fit with the second driver through the electromagnetic directional valve.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention.

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of an asymmetric vibratory injection system according to one embodiment;

FIG. 2 is a graph of injection speed versus injection time as described in one embodiment;

FIG. 3 is a graph of applied pressure versus injection time as described in one embodiment;

FIG. 4 is a first flow chart of an asymmetric vibration injection method according to an embodiment;

FIG. 5 is a second flow chart of the asymmetric vibratory injection method of one embodiment;

FIG. 6 is a third schematic flow chart of an asymmetric vibratory injection method according to one embodiment;

FIG. 7 is a fourth flowchart of the asymmetric vibratory injection method described in one embodiment.

100. An asymmetric vibrating injection system; 110. a charging barrel; 111. a material cavity; 112. a feed inlet; 113. shooting mouth; 114. a hopper; 120. an injection component; 121. a first driver; 122. a screw; 123. a coupling; 124. a heater; 125. a non-return ring; 130. a second driver; 140. an electric control device; 141. a hydraulic pump; 142. an electromagnetic directional valve; 143. a controller; 150. a slide base; 200. material preparation; 210. melting the materials; 220. an article of manufacture; 300. a mold; 310. and (4) an injection port.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In one embodiment, referring to fig. 1 and 4, an asymmetric vibration injection method includes the following steps:

s100, heating a charging barrel 110 to a preset temperature;

s200, starting a first driver 121 to drive the screw 122 to run in the barrel 110;

s300, putting the material 200 into the barrel 110, plasticizing the material 200 into a melt 210, and conveying the melt to a nozzle 113 of the barrel 110;

and S400, starting and controlling the output of the second driver 130 to enable the screw 122 to perform forward injection motion in the axial direction of the screw 122 and perform periodic reciprocating vibration, wherein in any vibration period, the screw 122 sequentially undergoes an acceleration stage and a deceleration stage, and the operation parameters in the acceleration stage are controlled to be different from the operation parameters in the deceleration stage, and the operation parameters comprise at least one of the injection speed vibration change mode and the injection speed vibration change time.

In the asymmetric vibration injection method, the first driver 121 is activated to drive the screw 122 to run in the barrel 110; then, the material 200 in the barrel 110 is plasticized into a melt 210 by means of the conveying and plasticizing functions of the screw 122, and is conveyed to the nozzle 113; finally, the output of the second driver 130 is enabled and controlled. At this time, the screw 122 is moved forward in its own axial direction for injection by the second driver 130 while being vibrated periodically back and forth. Because the screw 122 alternately goes through the acceleration stage and the deceleration stage in turn in any vibration cycle, and the operation parameters of the acceleration stage are different from the operation parameters of the deceleration stage, the screw 122 will make reciprocating acceleration and deceleration movement in the axial direction on the basis of the original operation, so as to realize the differential asymmetric vibration control of the screw 122 in the axial direction. Thus, the asymmetric vibration injection method optimizes the extrusion molding process by using the asymmetric vibration effect of the screw 122, and realizes precise control of the axial vibration of the screw 122, thereby improving the processing efficiency of the molded product 220 and the quality of the product 220.

It should be noted that the operating parameters in the acceleration phase are to be understood as being different from the operating parameters in the deceleration phase: the operating parameters of the screw 122 vibration during the acceleration phase and the deceleration phase are inconsistent, i.e., the operating parameters of the screw 122 during the acceleration phase and the deceleration phase are differentiated and asymmetric. Meanwhile, the injection speed vibration variation mode is an injection acceleration mode or an injection deceleration mode of the screw 122. In the acceleration stage or the deceleration stage, the screw 122 may perform the vibration change of the injection speed in a constant acceleration manner (the acceleration may be a positive value or a negative value, and a deceleration process is represented when the acceleration is a negative value), or may perform the vibration change of the injection speed in a gradual increase or decrease manner; of course, the acceleration of the screw 122 may be changed in a stepwise manner, such as increasing or decreasing, during the acceleration stage and the deceleration stage.

Alternatively, the first driver 121 may be an electric motor, an electric cylinder, a hydraulic cylinder, an oil cylinder, or the like. When the first actuator 121 is an electric cylinder, a hydraulic cylinder, or an oil cylinder, a power conversion structure is required to be added between the first actuator 121 and the screw 122 to convert the linear movement into the rotational movement. For example: the power conversion structure can be a rocker-crank structure and the like. Meanwhile, the second actuator 130 may also be an electric cylinder, a hydraulic cylinder, an oil cylinder, or the like.

It should be noted that, in the embodiment, the execution sequence between the step S100 and the step S200 may be executed first in the step S100; step S200 may also be performed first. Of course, step S100 and step S200 may also be performed simultaneously. In addition, the relationship between material 200, melt 210 and product 220 is: the material 200 is fed into the barrel 110 and forms a melt 210 upon heating and plasticizing by the screw 122. The formed melt 210 is injected into a mold 300 under the injection of a screw 122 to form an article 220.

Specifically, the execution sequence between step S100 and step S200 is: step S100 is executed first, and then step S200 is executed.

In addition, the forward injection movement of the screw 122 in the axial direction of the screw 122 while making the periodic reciprocating vibration should be understood as: when the second driver 130 is activated, the injection member 120 with the screw 122 is driven to perform forward injection movement in the direction of the mold 300. However, as the screw 122 undergoes an acceleration phase and then a deceleration phase, relative to the screw 122 itself, the screw 122 exhibits a relatively reciprocating periodic vibratory motion within the barrel 110.

Further, referring to fig. 1 and 2, the operation parameters include the vibration variation time of the injection speed, and the first time t taken for the acceleration from the first injection speed to the second injection speed in the acceleration stage₁Is less than the second time t for decelerating from the second injection speed to the first injection speed in the deceleration stage₂Refer to FIG. 2, V in FIG. 2₁At a first injection speed, V₂The second injection rate. Therefore, in any vibration period, the injection speed change time of the screw 122 in the acceleration stage and the deceleration stage is not consistent, so that the vibration of the screw 122 in the axial direction has asymmetry, and the vibration of the screw 122 is accurately and variously controlled. In addition, the first time t₁Less than the second time t₂Therefore, the screw 122 is ensured to impact forwards greatly and buffer backwards less in the injection process, so that the mold 300 product 220 is more compact, and the quality of the molded product 220 is further effectively improved.

Further, referring to fig. 1 and fig. 2, during the acceleration phase, the screw 122 is accelerated from the first injection speed to the second injection speed at a first constant acceleration, i.e. the screw 122 adopts a constant acceleration mode during the acceleration phase.

It should be noted that, in the deceleration phase, the screw 122 may decelerate at a constant acceleration, but the acceleration should be different from the acceleration in the acceleration phase; of course, the screw 122 may be decelerated at a variable acceleration.

In one embodiment, referring to fig. 1 and fig. 2, in the deceleration stage, the screw 122 decelerates from the second injection speed to the first injection speed at a second constant acceleration, and the second constant acceleration is smaller than the first constant acceleration. As can be seen, the screw 122 adopts a constant acceleration mode in both the acceleration stage and the deceleration stage. At the same time, it is also ensured that the second constant acceleration is less than the first constant acceleration setting to ensure that the screw 122 is vibrating asymmetrically during any cycle.

In an embodiment, referring to fig. 1 and fig. 5, the method further includes:

s500, after the injection operation is completed, a pressure that changes periodically is applied to the screw 122 along the axial direction of the screw 122 to maintain the pressure of the product 220 in the mold 300. Thus, after the injection, the screw 122 is applied with a periodically varying pressure, so that the product 220 is effectively maintained in pressure, thereby ensuring that the quality of the product 220 is further improved.

It should be noted that the pressing action on the screw 122 can be performed by the first driver 121 or the second driver 130. In this regard, the present embodiment is not particularly limited, and only needs to perform a pressure maintaining operation on the screw 122 after the injection is completed. In addition, in order to accurately control the pressure value on the screw 122, a pressure sensor or the like may be disposed on the screw 122 to obtain the pressure value on the screw 122 in real time.

It should also be noted that the periodically varying pressure should include at least a symmetrically periodically varying pressure and an asymmetrically periodically varying pressure. In this context, an asymmetrically periodically changing pressure is to be understood as: in any pressure applying period, when the screw 122 is applied with pressure, the data in the pressure increasing process and the pressure reducing process are inconsistent and are arranged asymmetrically.

Further, referring to fig. 1 and fig. 6, the step of applying a periodically varying pressure to the screw 122 along the axial direction of the screw 122 in S500 includes:

s510, in any pressure applying period, the pressure applied to the screw 122 along the axial direction of the screw 122 is increased from the first pressure to the second pressure, and the pressure increasing time is controlled to be a third time t₃；

S520, after the pressurization, the pressure applied to the screw 122 along the axial direction of the screw 122 is reduced from the second pressure to the first pressure, and the decompression time is controlled to be a fourth time t₄And a third time t₃Less than the fourth time t₄. In the pressure maintaining process of the present embodiment, an asymmetric periodically-varying pressure is applied to the screw 122, so that the pressure of the screw 122 is varied and differentially controlled, and the compacting effect of the product 220 of the mold 300 is better, specifically referring to fig. 3, where P in fig. 3₁Is a first pressure, P₂Is the second pressure.

In one embodiment, referring to fig. 1 and 7, the step of starting and controlling the output of the second driver 130 in S400 includes:

s410, starting the hydraulic pump 141 and the second driver 130;

and S420, opening and adjusting the electromagnetic directional valve 142, and controlling the hydraulic pump 141 to supply oil to the second driver 130 periodically. Accordingly, when controlling the output of the second driver 130, the hydraulic pump 141 is started; the electromagnetic directional valve 142 is opened to control the oil supply amount of the hydraulic pump 141 to the second actuator 130, so that the asymmetric periodic vibration of the screw 122 by the second actuator 130 is realized.

Specifically, the second actuator 130 is a cylinder.

In one embodiment, the method further comprises, before: prior to injection, the nozzle 113 of the cartridge 110 is inserted into the sprue 310 of the mold 300.

In one embodiment, referring to fig. 1, an asymmetric vibratory injection system 100 employs the asymmetric vibratory injection method of any of the above embodiments. The asymmetric vibratory injection system 100 comprises: a slide 150, a cartridge 110, an injection component 120, a second drive 130 and an electronic control device 140. The charging barrel 110 is provided with a material cavity 111 therein, and the charging barrel 110 is provided with a feeding hole 112 and a nozzle 113 which are communicated with the material cavity 111. The injection member 120 is slidably mounted on the slide carriage 150, and the injection member 120 includes a first driver 121, a screw 122 and a heater 124. A heater 124 is disposed on the cartridge 110. The screw 122 extends at least partially into the feed chamber 111. The first driver 121 is drivingly connected to the screw 122 to drive the screw 122. The second driver 130 is drivingly connected to the screw 122 to drive the screw 122 to move along the axial direction of the screw 122 while performing a periodic reciprocating vibration. The electronic control device 140 is in control cooperation with the second driver 130 to control the asymmetric periodic output of the second driver 130.

The asymmetric vibration injection system 100, using the above asymmetric vibration injection method, activates the first driver 121 to drive the screw 122 to operate in the barrel 110; then, the material 200 in the barrel 110 is plasticized into a melt 210 by means of the conveying and plasticizing functions of the screw 122, and is conveyed to the nozzle 113; finally, the output of the second driver 130 is started and controlled by the electronic control device 140. At this time, the screw 122 is moved forward in its own axial direction for injection by the second driver 130 while being vibrated periodically back and forth. Because the screw 122 alternately goes through the acceleration stage and the deceleration stage in turn in any vibration cycle, and the working parameters of the acceleration stage are different from the working parameters of the deceleration stage, the screw 122 will make reciprocating acceleration and deceleration movements in the axial direction on the basis of the original operation, so as to realize the differential asymmetric vibration control of the screw 122 in the axial direction. Thus, the asymmetric vibration injection method optimizes the extrusion molding process by using the asymmetric vibration effect of the screw 122, and realizes precise control of the axial vibration of the screw 122, thereby improving the processing efficiency of the molded product 220 and the quality of the product 220.

It should be noted that the sliding mounting of the injection component 120 on the slide carriage 150 may be, but is not limited to, a rail mounting manner. Meanwhile, the control of the asymmetric periodic output of the second driver 130 by the electronic control device 140 should be understood as: the output of the second driver 130 to the screw 122 is a periodic output, and in any period, the output curve is set asymmetrically, where the asymmetry includes both the injection speed vibration variation mode and the injection speed vibration variation time.

Specifically, referring to fig. 1, a hopper 114 is disposed on the barrel 110. The hopper 114 is in communication with the feed inlet 112.

Further, referring to fig. 1, the injection component 120 further includes a coupler 123. The output shaft of the first driver 121 is drivingly connected to the screw 122 through the coupling 123 to ensure that the torque of the first driver 121 is stably transmitted to the screw 122, so that the screw 122 stably runs in the barrel 110.

In one embodiment, referring to fig. 1, the electric control device 140 includes a hydraulic pump 141, a solenoid directional valve 142, and a controller 143. The hydraulic pump 141 and the electromagnetic directional valve 142 are electrically connected to the controller 143. The hydraulic pump 141 is in control cooperation with the second driver 130 through the electromagnetic directional valve 142, so that the hydraulic pump 141 is started when the output of the second driver 130 is controlled; the electromagnetic directional valve 142 is opened to control the oil supply amount of the hydraulic pump 141 to the second actuator 130, so that the asymmetric periodic vibration of the screw 122 by the second actuator 130 is realized.

In one embodiment, referring to fig. 1, a non-return ring 125 is sleeved on the screw 122 to prevent the melt 210 from flowing backward in the barrel 110 during the injection process, thereby ensuring the injection process to be performed stably.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Claims

1. An asymmetric vibratory injection method, comprising the steps of:

heating the charging barrel to a preset temperature;

starting a first driver to drive the screw to run in the barrel;

putting a material into a charging barrel, plasticizing the material into a melt, and conveying the melt to a nozzle of the charging barrel;

and starting and controlling the output of a second driver to enable the screw to perform forward injection motion in the axis direction of the screw and perform periodic reciprocating vibration, wherein the screw sequentially goes through an acceleration stage and a deceleration stage in any vibration period, and the operation parameters in the acceleration stage are controlled to be different from the operation parameters in the deceleration stage, and the operation parameters comprise at least one of an injection speed vibration change mode and an injection speed vibration change time.

2. The asymmetric vibration injection method of claim 1 wherein said operational parameter comprises injection velocity vibration variation time and a first time t for acceleration from a first injection velocity to a second injection velocity in said acceleration phase₁Less than a second time t taken for decelerating from the second injection speed to the first injection speed in the deceleration stage₂。

3. The asymmetric vibratory injection method of claim 2 wherein during the acceleration phase the screw accelerates from the first injection velocity to the second injection velocity at a first constant acceleration.

4. The asymmetric vibratory injection method of claim 3 wherein during the deceleration phase the screw decelerates from the second injection velocity to the first injection velocity at a second constant acceleration, and the second constant acceleration is less than the first constant acceleration.

5. The asymmetric vibratory injection method of claim 1, further comprising:

after the injection action is finished, applying a periodically-changed pressure to the screw along the axial direction of the screw so as to maintain the pressure of the product in the mold.

6. The asymmetric vibration injection method as claimed in claim 5, wherein the step of applying a periodically varying pressure to said screw in an axial direction of said screw comprises:

in any pressure applying period, the pressure applied to the screw along the axial direction of the screw is increased from the first pressure to the second pressure, and the pressurizing time is controlled to be the third time t₃；

After the pressurization, the pressure applied to the screw in the axial direction of the screw is reduced from the second pressure to the first pressure, and the decompression time is controlled to be a fourth time t₄And the third time t₃Less than the fourth time t₄。

7. The asymmetric vibration injection method of any of claims 1 to 6 wherein the step of activating and controlling the output of the second driver comprises:

starting a hydraulic pump and the second driver;

and opening a solenoid directional valve, and controlling the hydraulic pump to periodically supply oil to the second driver.

8. An asymmetric vibration injection system, wherein the asymmetric vibration injection method of any of claims 1 to 7 is employed, the asymmetric vibration injection system comprising:

a slide base;

the charging barrel is internally provided with a material cavity, and a feeding hole and a nozzle which are communicated with the material cavity are arranged on the charging barrel;

the injection component is arranged on the sliding seat in a sliding manner and comprises a first driver, a screw rod and a heater, the heater is arranged on the material barrel, at least one part of the screw rod extends into the material cavity, and the first driver is in driving connection with the screw rod so as to drive the screw rod to run;

the second driver is in driving connection with the screw rod so as to drive the screw rod to move along the axial direction of the screw rod and simultaneously perform periodic reciprocating vibration;

and the electric control device is in control coordination with the second driver so as to control the asymmetric periodic output of the second driver.

9. The asymmetric vibration injection system of claim 8 wherein said injection component further comprises a coupling, said output shaft of said first driver being drivingly connected to said screw through said coupling.

10. The asymmetric vibration injection system as in claim 8, wherein said electrical control device comprises a hydraulic pump, a solenoid directional valve and a controller, said hydraulic pump and said solenoid directional valve are electrically connected to said controller, and said hydraulic pump is in control cooperation with said second driver through said solenoid directional valve.