Injection molding non-return device and injection molding machine

Abstract

The utility model discloses an injection molding non-return device and an injection molding machine, and relates to the technical field of injection molding, the injection molding non-return device comprises a non-return assembly, the non-return assembly comprises a non-return screw head, a non-return body and a non-return seat, the non-return screw head is provided with a channel, the channel comprises a material passing groove, a supporting seat and a material outlet, a plurality of supporting seats which are arranged in a protruding manner are arranged on the inner wall of the material passing groove in the circumferential direction; a feeding port and a sealing face are sequentially arranged on the non-return base in the flowing direction of melt, the sealing face is located on the side, back on to the non-return screw head, of the non-return body, and in the mold filling and pressure maintaining stage, the outer wall of the non-return body can be attached to the sealing face under pushing of the pressure of the melt, so that blocking of the feeding port and the discharging port is achieved. The melt with pressure pushes the non-return body to achieve sealing, the sealing effect can be guaranteed under different temperatures and different pressures, the adaptability to different materials or different technologies can be improved, and the sealing effect is stable.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molding, in particular to an injection molding anti-reverse device and an injection molding machine. Background Art

[0002] In the related art, in the process of injection molding of polymer materials, screw injection machines are currently generally used to achieve injection. Melt backflow is prone to occur during the mold filling and pressure holding stages. Therefore, in the prior art, a check ring is usually set in the injection machine to achieve pressure holding sealing. The check ring achieves sealing by cooperating between its radial outer wall and the inner wall of the barrel. During operation, the check ring will make reciprocating axial motion in the barrel with the screw. Due to temperature changes, the check ring and the barrel will produce different degrees of deformation, and the melt temperature and holding pressure required for molding products of different materials are different, resulting in large fluctuations in the sealing effect during actual use, which will cause the seal to fail and fail to maintain pressure. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides an injection molding anti-return device and an injection molding machine to improve the process adaptability and sealing performance of different materials.

[0004] According to the first aspect of the present invention, an injection molding anti-return device includes:

[0005] A screw, a barrel and a check assembly, wherein the check assembly is located in the barrel and fixedly connected to one end of the screw;

[0006] The anti-return assembly comprises: an anti-return screw head, an anti-return body and an anti-return seat which are sequentially arranged along the axis direction of the anti-return assembly; at least three groups of channels are evenly arranged on the anti-return screw head in the circumferential direction; the channels include a feed trough, a support seat and a discharge port; a plurality of protruding support seats are provided on the inner wall of the feed trough along the circumferential direction; a feed port and a sealing surface are sequentially provided on the anti-return seat along the flow direction of the melt; the sealing surface is located on the side of the anti-return body facing away from the anti-return screw head; the feed port and the discharge port are the same in number and are connected one by one;

[0007] The support seat can maintain a gap between the check body and the feed chute to allow the melt to pass through, thereby enabling the melt to be discharged from the barrel for injection molding; during the mold filling and pressure holding stage, the outer wall of the check body can fit against the sealing surface under the pressure of the melt, thereby blocking the feed port and the discharge port.

[0008] An injection molding anti-return device according to an embodiment of the first aspect of the utility model has at least the following beneficial effects: this embodiment is provided with an anti-return component, the anti-return component includes a anti-return screw head, a anti-return body and a anti-return seat, the anti-return screw head is provided with a channel, the channel includes a feed trough, a support seat and a discharge port, and the inner wall of the feed trough along the circumferential direction is provided with a plurality of protruding support seats; the anti-return seat is provided with a feed port and a sealing surface in sequence along the flow direction of the melt, the sealing surface is located on the side of the anti-return body facing away from the anti-return screw head, the support seat can maintain a gap between the anti-return body and the feed trough to allow the melt to pass through, in the mold filling and holding pressure stage, the outer wall of the anti-return body can fit the sealing surface under the push of the melt pressure, thereby achieving the blocking of the feed port and the discharge port, therefore, during the holding pressure, the anti-return body is pushed by the pressurized melt to achieve sealing, the sealing effect can be guaranteed under different temperatures and different pressures, the adaptability to different materials or different processes can be improved, and the sealing effect is stable.

[0009] According to the embodiment of the first aspect of the utility model, both the feed port and the discharge port are provided with a narrowing portion with a reduced inner diameter, the feed chute is located at the upstream end of the discharge port, and the sealing surface is located at the downstream end of the feed port.

[0010] According to the embodiment of the first aspect of the utility model, a ring-shaped distribution groove is provided on the anti-return seat, and the distribution groove can connect the feed port with the inner cavity of the barrel.

[0011] According to the embodiment of the first aspect of the utility model, a connecting section connected with the material passing chute is provided on the anti-reverse seat, and a supporting part is provided in the connecting section, and the supporting part is connected to the supporting seat.

[0012] According to an embodiment of the first aspect of the utility model, the distribution groove has an arc-shaped bottom wall, and the distribution groove is connected to a plurality of feed ports at the same time to improve the injection efficiency.

[0013] According to an embodiment of the first aspect of the utility model, a nozzle is provided at the end of the barrel, and the nozzle is connected to the discharge port.

[0014] According to an embodiment of the first aspect of the utility model, a connector is provided between the nozzle and the end of the barrel, and both ends of the connector are connected to the nozzle and the discharge port.

[0015] According to the embodiment of the first aspect of the utility model, the anti-return body is spherical or ellipsoidal, the sealing surface is a spherical surface, and the major axis direction of the ellipsoidal anti-return body is consistent with the melt flow direction.

[0016] According to an embodiment of the first aspect of the utility model, the check screw head is fixed to the screw by means of a threaded connection.

[0017] An injection molding machine according to an embodiment of the second aspect of the utility model includes an injection molding anti-reverse device according to an embodiment of the first aspect of the utility model.

[0018] An injection molding machine according to an embodiment of the second aspect of the utility model has at least the following beneficial effects: compared with the prior art, the injection molding machine is provided with a non-return assembly including a non-return screw head, a non-return body and a non-return seat, the non-return screw head is provided with a channel, the channel includes a feed trough, a support seat and a discharge port, and the feed trough is provided with a plurality of protruding support seats on the inner wall along the circumferential direction; the non-return seat is provided with a feed port and a sealing surface in sequence along the flow direction of the melt, the sealing surface is located on the side of the non-return body facing away from the non-return screw head, the support seat can maintain a gap between the non-return body and the feed trough to allow the melt to pass through, in the mold filling and pressure holding stage, the outer wall of the non-return body can fit the sealing surface under the push of the melt pressure, thereby achieving the blocking of the feed port and the discharge port, therefore, during the pressure holding, the pressurized melt pushes the non-return body to achieve sealing, the sealing effect can be guaranteed under different temperatures and different pressures, the adaptability to different materials or different processes can be improved, and the pressure holding effect of the injection molding machine can be improved.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is further described below with reference to the accompanying drawings and embodiments, wherein:

[0021] Figure 1 A cross-sectional view of an injection molding anti-return device in an embodiment of the first aspect of the utility model;

[0022] Figure 2 A first cross-sectional view of a non-return screw head, a non-return seat and a non-return body in an embodiment of the first aspect of the utility model;

[0023] Figure 3 An exploded sectional view of a non-return screw head and a non-return seat in an embodiment of the first aspect of the utility model;

[0024] Figure 4 A cross-sectional view of an embodiment of the first aspect of the utility model;

[0025] Figure 5 for Figure 2 A section view in;

[0026] Figure 6 A second cross-sectional view of the anti-reverse screw head, the anti-reverse seat and the anti-reverse body in the embodiment of the first aspect of the utility model;

[0027] Figure 7 for Figure 6 Section B in the figure.

[0028] Reference numerals:

[0029] Screw 1; Barrel 2;

[0030] The backflow prevention assembly 3; the backflow prevention screw head 31; the material feeding groove 311; the support seat 312; the material outlet 313; the backflow prevention body 32; the backflow prevention seat 33; the distribution groove 331; the material inlet 332; the sealing surface 333; the connecting section 334; the support part 335;

[0031] Connecting head 4; nozzle 5. DETAILED DESCRIPTION

[0032] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0033] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0034] In the description of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0035] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0036] Reference Figure 1 In the first aspect of the present invention, an injection molding non-return device includes a rod 1, a barrel 2 and a non-return assembly 3. The non-return assembly 3 is located in the barrel 2 and is fixedly connected to one end of the screw 1. It can be understood that the screw 1 rotates in the barrel 2, and the outer wall of the screw 1 has threads. When the screw 1 rotates, the melt is transported along the axis direction of the barrel 2, and the melt is discharged from the non-return assembly 3.

[0037] Reference Figure 2The anti-return assembly 3 includes a head of the anti-return screw 1, a anti-return body 32 and a anti-return seat 33. Along the flow direction of the melt, the anti-return seat 33, the anti-return body 32 and the head of the anti-return screw 1 are arranged in sequence. It can be understood that the anti-return body 32 is spherical and can move between the head of the anti-return screw 1 and the anti-return seat 33. Further, the anti-return body 32 can also be ellipsoidal, and the long axis direction of the ellipsoidal anti-return body 32 is consistent with the flow direction of the melt. It can be understood that the head of the anti-return screw 1 is fixed to the screw 1 by a threaded connection, that is, the head of the anti-return screw 1 is screwed to the end of the screw 1.

[0038] Reference Figure 3 , at least three groups of channels are evenly arranged in the circumferential direction on the head of the check screw 1. It can be understood that the provision of multiple channels can reasonably distribute the pressure and help improve the efficiency of injection. The channel includes a feed trough 311, a support seat 312 and a discharge port 313. It can be understood that along the flow direction of the melt, the feed trough 311 is located at the upstream end of the discharge port 313. Along the axis of the discharge port 313, the feed trough 311 is a ring-shaped groove. The check body 32 is located in the feed trough 311. There are several protruding support seats 312 on the inner wall of the feed trough 311 along the circumferential direction. The outer wall of the check body 32 can abut against the side wall of the support seat 312. Therefore, there is a gap between the check body 32 and the inner wall of the feed trough 311. During the mold filling and injection process, the melt can be discharged to the discharge port 313 through the gap.

[0039] Further, refer to Figure 4 A feed port 332 and a sealing surface 333 are sequentially arranged on the anti-return seat 33 along the flow direction of the melt. The sealing surface 333 is located on the side of the anti-return body 32 facing away from the head of the anti-return screw 1. During the mold filling and pressure holding stage, the outer wall of the anti-return body 32 can fit against the sealing surface 333 under the pressure of the melt, thereby blocking the feed port 332 and the discharge port 313 and achieving sealing.

[0040] Reference Figure 2 Both the feed port 332 and the discharge port 313 are provided with a narrowing portion with a reduced inner diameter, so that the melt is subjected to the combined effects of shear stress and normal stress during the flow process. The normal stress is mainly responsible for pushing the melt to fill the mold cavity along the axial direction, ensuring that the melt can quickly and fully fill the mold space with complex geometric shapes. The shear stress helps the melt change its flow direction at corners, thin walls and flow channel turning points, promotes the melt to be evenly distributed in various parts and fit the mold wall, and thus helps to optimize the filling effect.

[0041] It can be understood that the anti-return seat 33 and the anti-return screw 1 are sealed. Figure 4The anti-return seat 33 is provided with a connecting section 334 connected with the feed chute 311, and a support portion 335 is provided in the connecting section 334, and the support portion 335 is connected to the support seat 312. It can be understood that the inner wall of the connecting section 334 is connected with the inner wall of the feed chute 311, and the connecting section 334 and the feed chute 311 are combined to form a cavity that allows the anti-return body 32 to move along the flow direction of the melt. At the same time, the support portion 335 is connected with the support seat 312, so that the anti-return body 32 can move stably in the cavity. Furthermore, along the flow direction of the melt, there is also a gap between the radial side wall of the downstream end of the feed chute 311 and the anti-return body 32. Therefore, during the injection process, refer to Figure 5 When the check body 32 approaches the downstream end of the feed channel 311 under the push of the melt, the feed channel 311 can still allow the melt to be discharged and the mold can be filled.

[0042] It can be understood that, around the flow direction of the melt, the inner diameter of the feed port 332 is smaller than the inner diameter of the feed slot 311, and a sealing surface 333 is provided at the downstream end of the feed port 332, and the sealing surface 333 is a spherical surface that can cooperate with the outer wall surface of the check body 32. Figure 6 and Figure 7 When the pressure is maintained, the melt pressure in the mold is relatively high, and the melt will flow back. Therefore, under the reverse pressure of the melt, the outer wall of the backflow stop 32 abuts against the sealing surface 333, thereby cutting off the flow path of the melt, so that the melt cannot flow back further into the barrel 2, and the pressure can be maintained in this process. Furthermore, since the sealing surface 333 is located at the end of the backflow stop 32 away from the discharge port 313, compared with the prior art using radial sealing, the technical solution of the present application is not affected by temperature changes or pressure changes, and can ensure a good sealing effect at different temperatures and different pressures, which can improve the adaptability to different materials or different processes, and the sealing effect is stable.

[0043] Reference Figure 4 The check seat 33 is provided with an annular distribution groove 331, which is located at the upstream end of the check seat 33 along the flow direction of the melt. The distribution groove 331 can connect the feed port 332 with the inner cavity of the barrel 2, and the distribution groove 331 can connect several feed ports 332. It can be understood that the check seat 33 allows several feed ports 332 to discharge the melt through the distribution groove 331, which helps to achieve uniform distribution of injection pressure. Furthermore, the distribution groove 331 has an arc-shaped bottom wall, which helps to increase the flow efficiency of the melt and prevent the melt from staying in the corner to improve the injection efficiency.

[0044] Reference Figure 1The end of the barrel 2 is provided with a nozzle 5, which is connected to the discharge port 313. It can be understood that the nozzle 5 is inserted into the mold for injection molding. Further, a connector 4 is provided between the nozzle 5 and the end of the barrel 2, and both ends of the connector 4 are connected to the nozzle 5 and the discharge port 313. In addition, along the direction of melt flow, a cavity that can accommodate the melt is provided between the radial inner wall of the connector 4 and the outer wall of the check screw 1 head, which can ensure that the melt can be filled in the mold cavity of the mold during the pressure holding process.

[0045] An injection molding machine according to an embodiment of the second aspect of the utility model includes an injection molding anti-return device according to an embodiment of the first aspect of the utility model. Since the injection molding machine adopts all the technical solutions of the injection molding anti-return device of the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment.

[0046] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. An injection molding anti-return device, It is characterized in that include: A screw, a barrel and a non-return assembly, wherein the non-return assembly is located in the barrel and fixedly connected to one end of the screw; The anti-return assembly comprises: an anti-return screw head, an anti-return body and an anti-return seat arranged in sequence along the axial direction of the anti-return assembly, at least three groups of channels are evenly arranged in the circumferential direction on the anti-return screw head, the channels include a feed trough, a support seat and a discharge port, and a plurality of protruding support seats are provided on the inner wall of the feed trough along the circumferential direction; a feed port and a sealing surface are arranged in sequence on the anti-return seat along the flow direction of the melt, the sealing surface is located on the side of the anti-return body facing away from the anti-return screw head, the feed port and the discharge port are the same in number and are connected one by one; The support seat can maintain a gap between the check body and the feed chute to allow the melt to pass through, thereby enabling the melt to be discharged from the barrel for injection molding; in the mold filling and pressure holding stage, the outer wall of the check body can fit against the sealing surface under the pressure of the melt, thereby blocking the feed port and the discharge port.

2. An injection molding anti-return device according to claim 1, It is characterized in that The feed port and the discharge port are both provided with a narrowing portion with a reduced inner diameter, the feed trough is located at the upstream end of the discharge port, and the sealing surface is located at the downstream end of the feed port.

3. The injection molding anti-return device according to claim 1, It is characterized in that The anti-return seat is provided with an annular distribution groove, and the distribution groove can connect the feed port with the inner cavity of the barrel.

4. The injection molding anti-return device according to claim 1, It is characterized in that The anti-return seat is provided with a connecting section connected with the material passing chute, and a supporting part is provided in the connecting section, and the supporting part is connected with the supporting seat.

5. The injection molding anti-return device according to claim 3, It is characterized in that The distribution groove has an arc-shaped bottom wall, and the distribution groove is connected to a plurality of the feed ports at the same time to improve the injection efficiency.

6. The injection molding anti-return device according to claim 1, It is characterized in that A nozzle is provided at the end of the barrel, and the nozzle is communicated with the discharge port.

7. The injection molding anti-return device according to claim 6, It is characterized in that A connector is provided between the nozzle and the end of the barrel, and both ends of the connector are connected to the nozzle and the discharge port.

8. The injection molding anti-return device according to claim 1, It is characterized in that The anti-return body is spherical or ellipsoidal, the sealing surface is a spherical surface, and the major axis direction of the ellipsoidal anti-return body is consistent with the flow direction of the melt.

9. The injection molding anti-return device according to claim 1, It is characterized in that The anti-return screw head is fixed to the screw by threaded connection.

10. An injection molding machine, It is characterized in that The invention comprises an injection molding anti-return device as claimed in any one of claims 1 to 9.

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