Injection molding screw structure of an injection molding machine

Abstract

The utility model provides an injection molding screw structure of an injection molding machine. The injection molding screw structure of the injection molding machine includes a screw head, a screw middle part and a screw tail part which are arranged in sequence: the spiral middle part includes at least three branches, each branch has a cavity inside, adjacent branches are spliced ​​into one body through a center limit, and keep the head and tail fitting together, and multiple branches are spliced ​​and fixed by threaded parts; when the threaded parts are locked, the screw middle part spliced ​​into multiple branches is in a state of being fastened into one body with the screw head and the screw tail; when the threaded parts are disengaged, the screw head, the screw middle part and the screw tail are in a separate state. The utility model facilitates the positioning and splicing of each branch and fixes them into one body through the mutual cooperation of the limit structure and the threaded structure, reduces the difficulty of splicing, and is also easy to improve the stability of the connection.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molding machines, in particular to an injection molding screw structure of an injection molding machine. Background Art

[0002] The injection screw is an important part of the injection molding machine. Its function is to convey, compact, melt, stir and pressurize the plastic. Most of the existing injection screws are integrally formed. After wear occurs, the entire injection screw needs to be replaced. However, if the worn part is only a small part of the injection screw, and not the entire screw is worn, this replacement method is wasteful. Therefore, the use of a split screw is more conducive to the situation where some parts of the screw are prone to wear. Only the worn part needs to be replaced, and the rest is retained to reduce waste. However, most of the existing split screws are simply bolted, and the coaxiality cannot be guaranteed during splicing. Moreover, relying solely on bolt connections, it is easy to split, which increases the failure rate during use. Utility Model Content

[0003] Based on this, it is necessary to provide an injection molding screw structure for an injection molding machine to address the problems of difficult splicing and easy failure of the existing split screws that only rely on bolt connection.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] The invention discloses an injection molding screw structure for an injection molding machine, comprising a screw head, a middle screw part and a screw tail part which are arranged in sequence: the middle screw part comprises at least three branches, each branch has a cavity inside, adjacent branches are spliced ​​into one body through a center limit, and keep the head and tail fitting together, a plurality of branches are spliced ​​and fixed by a threaded component, when the threaded component is locked, the middle screw part spliced ​​into the plurality of branches is in a state of being fastened as one body with the screw head and the screw tail; when the threaded component is detached, the screw head, the middle screw part and the screw tail are in a separate state.

[0006] Furthermore, the joints of adjacent branches, the joints of the branch and the screw head, and the joints of the branch and the screw tail are inclined, and the screw ridges are staggered; the tail end of the screw head and the tail end of the branch are fixedly connected to a limiting rod, and a cavity is axially penetrated through the center of the screw tail and the branch, and the diameter of the cavity matches the diameter of the limiting rod, and the limiting rod of the screw head and the branch is embedded in the cavity of the adjacent branch or the screw tail to form a whole.

[0007] Furthermore, the embedded end of the limiting rod gradually reduces in diameter radially outward and takes a frustum shape.

[0008] Furthermore, the threaded component includes a limiting bolt; the outer surface of one end of the screw head and the branch has a limiting rod with an annular groove opened along the inclined trajectory of the end, and the limiting bolt is axially arranged inside the annular groove, and the end of the limiting bolt of the screw head and the branch extends to the head end of the adjacent branch or the tail of the screw.

[0009] Furthermore, sealing gaskets for covering the limiting bolts are embedded in the annular grooves of the screw head and the branch.

[0010] Furthermore, the joints of adjacent branches, the joints of the branch and the screw head, and the joints of the branch and the screw tail are flat and staggered with the screw ribs; the tail end of the screw head and the tail end of the branch are fixedly connected with a limiting rod, and a cavity is axially penetrated through the center of the screw tail and the branch, and the diameter of the cavity matches the diameter of the limiting rod, and the limiting rod of the screw head and the branch is embedded in the cavity of the adjacent branch or the screw tail to form a whole.

[0011] Furthermore, the threaded component includes a limiting bolt; the limiting bolt is radially arranged at the branch and the tail of the screw rod, the end of the limiting bolt extends into the limiting rod, the limiting bolt is staggered, and the screw rib part is staggered.

[0012] Furthermore, the threaded component includes a limiting straight rod and a limiting nut; the limiting straight rod is fixedly connected to the center of the screw head, and a cavity adapted to the limiting straight rod is opened at the center of each branch. Multiple branches are sleeved on the outer surface of the limiting straight rod, and the end of the limiting straight rod extends to the tail of the screw through the cavity of the branch. The limiting nut is threadedly connected to the end of the limiting straight rod and is tightly attached to the tail of the screw.

[0013] Furthermore, a groove is radially opened on the end face of the tail end of the screw, the limiting straight rod extends into the groove, and the limiting nut is located in the groove and fits the inner wall of the groove.

[0014] Furthermore, a plurality of through holes are radially opened inside the branch, and the through holes are located at the periphery of the cavity of the branch.

[0015] Compared with the prior art, the beneficial effects of the utility model include:

[0016] 1. The utility model facilitates the positioning and splicing of each branch and fixes them together through the cooperation of the limiting structure and the threaded structure, thereby reducing the difficulty of splicing and improving the stability of the connection;

[0017] 2. The utility model can reduce the use of screw materials by setting the internal cavity of the branch, and is also easy to limit the splicing. At the same time, the splicing part and the screw rib part are staggered, which does not affect the normal use of the injection molding screw. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The disclosure of the present invention is described with reference to the accompanying drawings. It should be understood that the drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings, the same reference numerals are used to refer to the same components. Among them:

[0019] Figure 1 This is a three-dimensional diagram of an injection molding screw structure of an injection molding machine introduced in the utility model;

[0020] Figure 2 A cross-sectional view of the injection molding screw structure of the injection molding machine introduced in Example 1;

[0021] Figure 3 Based on Figure 2 A magnified image of point A;

[0022] Figure 4 A cross-sectional view of the injection molding screw structure of the injection molding machine introduced in Example 2;

[0023] Figure 5 Based on Figure 4 The enlarged view of point B;

[0024] Figure 6 This is a cross-sectional view of the injection molding screw structure of the injection molding machine introduced in Example 3.

[0025] Notes in the figure: 1. Screw head; 2. Middle part of screw; 21. Branch; 22. Limit rod; 23. Limit bolt; 24. Sealing gasket; 25. Limit straight rod; 26. Limit nut; 27. Through hole; 3. Screw tail. DETAILED DESCRIPTION

[0026] It is easy to understand that according to the technical solution of the utility model, without changing the essential spirit of the utility model, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the utility model, and should not be regarded as the entirety of the utility model or as a limitation or restriction to the technical solution of the utility model.

[0027] Example 1

[0028] See also Figure 1 This embodiment introduces an injection molding screw structure of an injection molding machine, which mainly includes a screw head 1, a screw middle part 2 and a screw tail 3 arranged in sequence. The screw middle part 2 is composed of at least three branches 21, and the screw head 1 and the branch 21, the adjacent branch 21 and the branch 21 and the screw tail 3 are fitted end to end and spliced ​​into one through a center limit, and multiple branches 21 and the branch 21 and the thread head 1 and the thread tail 3 are spliced ​​and fixed through threaded parts.

[0029] The center of the screw tail 3 and the branch 21 is provided with a cavity along the axial direction, and the screw head 1 and the tail end of the branch 21 are fixedly connected with a limit rod 22, and the limit rod 22 has a certain length. It should be noted that part of the limit rod 22 of the branch 21 is fixed in the cavity, and part is located outside the cavity. The limit rod 22 gradually decreases in diameter radially outward and is truncated, which is convenient for guiding the end of the limit rod 22 into the cavity of the branch 21 or the screw tail 3.

[0030] The joints of adjacent branches 21, the joints of the branches 21 and the screw head 1, and the joints of the branches 21 and the screw tail 3 are inclined surfaces, and the screw fins are staggered. The setting of the inclined surfaces is more conducive to staggering the screw fins and reasonably utilizing the gaps between the screw fins. When splicing, the branches 21 can be spliced ​​together to form the screw middle part 2 first, and then the screw head 1 and the screw tail 3 are spliced.

[0031] The threaded component of this embodiment adopts a limiting bolt 23. The outer surface of one end of the screw head 1 and the branch 21 with the limiting rod 22 is provided with an annular groove along the inclined track of the end, and the annular groove is kept at a fixed distance from the end. The annular groove is provided with a plurality of through holes, and the end surface of the branch 21, the screw tail 3 and the limiting rod 22 are also provided with screw holes corresponding to the number of through holes, and the limiting bolt 23 passes through the through holes and is threadedly connected with the screw holes, so that the joints of adjacent branches 21, the joints of the branch 21 and the screw head 1, and the joints of the branch 21 and the screw tail 3 are fixed together.

[0032] Inserting the sealing gasket 24 into the annular groove can block the limiting bolt 23 and the gap of the annular groove, thereby reducing the blockage. The sealing gasket 24 may not be a whole, but may be composed of multiple blocks, and a notch is provided at the portion where the sealing gasket 24 contacts the limiting bolt 23, so that the sealing gasket 24 is not blocked by the limiting bolt 23 when inserted.

[0033] The specific splicing process is to first insert the limiting rod 22 of the screw head 1 and the branch 21 into the cavity of the adjacent branch 21 and the screw tail 3. The limiting rod 22 and the cavity are clearance-matched, and have a certain splicing and fixing operation. After the adjacent end faces are fitted, tighten the limiting bolt 23, and then insert the sealing gasket 24 to complete the splicing operation.

[0034] When the screw head 1, branch 21 or screw tail 3 is worn and needs to be replaced, the sealing gasket 24 can be removed, the limit bolt 23 can be loosened and disengaged from the screw hole, and then the limit rod 22 can be pulled out of the cavity to complete the separation operation, and then the splicing operation can be repeated to connect the new parts that need to be spliced ​​together.

[0035] In this embodiment, the limiting rod and the limiting bolt cooperate with each other, so that each branch 21 is conveniently positioned and fixed as a whole after splicing, which reduces the difficulty of splicing and is easy to improve the stability of the connection.

[0036] Example 2

[0037] This embodiment introduces an injection molding screw structure for an injection molding machine, which is basically the same as the overall structure of the injection molding screw structure for an injection molding machine introduced in Example 1. The difference is that the splicing of adjacent branches 21, the splicing of branches 21 and the screw head 1, and the splicing of branches 21 and the screw tail 3 in this embodiment are flat and staggered. The limit bolts 23 are arranged radially, and the surfaces of the branches 21 and the screw tail 3 are radially opened with multiple holes that can allow the limit bolts 23 to pass through, and the surface of the limit rod 22 is radially opened with screw holes, and multiple limit bolts 23 are staggered. The ends of the limit bolts 23 pass through the holes and are threadedly connected with the screw holes. After the limit rod 22 enters the cavity, the limit bolts 23 are further connected. Multiple limit bolts 23 are staggered to avoid the screw ribs. Compared with Example 1, this embodiment is simpler in structure, but the heads of the limit bolts 23 are exposed.

[0038] This embodiment has the same beneficial effects as Embodiment 1.

[0039] Example 3

[0040] This embodiment introduces an injection molding screw structure of an injection molding machine, which is basically the same as the overall structure of the injection molding screw structure of the injection molding machine introduced in Example 1. The difference is that the threaded component of this embodiment includes a limiting straight rod 25 and a limiting nut 26; the limiting straight rod 25 is fixedly connected to the center of the screw head 1, the length direction of the limiting straight rod 25 is consistent with the axial direction of the injection molding screw, and the inner center of the multiple branches 21 has a cavity, and the cavity diameter is adapted to the diameter of the limiting straight rod 25, so that the branch 21 can be sleeved on the outer surface of the limiting straight rod 25, and the screw tail 3 also has the same cavity, so that the limiting straight rod 25 can pass through the screw tail 3. The end of the limiting straight rod 25 away from the screw head 1 is threadedly connected to the limiting nut 26, and by tightening the limiting nut 26, the end faces of the screw head 1, the branch 21 and the screw tail 3 can be tightly attached together.

[0041] A groove with a diameter larger than the limiting straight rod 25 can be opened at the tail end of the screw tail 3, and the limiting nut 26 can be accommodated in the groove, so that the end of the limiting straight rod 25 and the limiting nut 26 are both located in the groove, and the limiting nut 26 is tightened so that the end of the limiting nut 26 is close to the inner wall of the groove, so that the thread head, the middle part of the thread formed by the branch 21, and the thread tail are tightly fitted and connected as a whole. In order to reduce the weight of the branch 21 and reduce the use of materials, a plurality of through holes 27 can be opened radially inside the branch 21, and the through holes 27 are located on the periphery of the cavity of the branch 21. The connection operation of this embodiment is simple, but the fastening is slightly weak.

[0042] This embodiment has the same beneficial effects as Embodiment 1.

[0043] The technical scope of the present invention is not limited to the contents described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical concept of the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. An injection molding screw structure of an injection molding machine, characterized in that: The invention comprises a screw head (1), a screw middle part (2) and a screw tail (3) which are arranged in sequence: the screw middle part (2) comprises at least three branches (21), each branch (21) has a cavity inside, adjacent branches (21) are spliced ​​into one body through a center limiter and keep the head and tail close to each other, and a plurality of branches (21) and the branches (21) and the screw head (1) and the screw tail (3) are spliced ​​and fixed through a threaded component; when the threaded component is locked, the screw middle part (2) spliced ​​into the plurality of branches (21) and the screw head (1) and the screw tail (3) are in a state of being fastened into one body; when the threaded component is disengaged, the screw head (1), the screw middle part (2) and the screw tail (3) are in a separate state.

2. The injection molding screw structure of the injection molding machine according to claim 1, characterized in that: The joints of adjacent branches (21), the joints of the branches (21) and the screw head (1), and the joints of the branches (21) and the screw tail (3) are in the form of inclined surfaces, and the screw ridges are staggered; the tail end of the screw head (1) and the tail end of the branch (21) are fixedly connected to a limiting rod (22); the center of the screw tail (3) and the branch (21) is provided with a cavity along the axial direction, the diameter of the cavity matches the diameter of the limiting rod (22); the limiting rod (22) of the screw head (1) and the branch (21) is embedded in the cavity of the adjacent branch (21) or the screw tail (3) to form a whole.

3. The injection molding screw structure of the injection molding machine according to claim 2, characterized in that: The embedded end of the limiting rod (22) gradually reduces in diameter radially outwards and is in a truncated cone shape.

4. The injection molding screw structure of the injection molding machine according to claim 2, characterized in that: The threaded component comprises a limiting bolt (23); the screw head (1) and the branch (21) have an annular groove formed on the outer surface of one end of the limiting rod (22) along an end inclined trajectory, the limiting bolt (23) is axially arranged inside the annular groove, and the end of the limiting bolt (23) of the screw head (1) and the branch (21) extends into the head end of the adjacent branch (21) or the screw tail (3).

5. The injection molding screw structure of the injection molding machine according to claim 4, characterized in that: A sealing gasket (24) for shielding the limiting bolt (23) is embedded in the annular groove of the screw head (1) and the branch (21).

6. The injection molding screw structure of the injection molding machine according to claim 1, characterized in that: The joints of adjacent branches (21), the joints of the branches (21) and the screw head (1), and the joints of the branches (21) and the screw tail (3) are flat and staggered with the screw ridges; the tail end of the screw head (1) and the tail end of the branch (21) are fixedly connected with a limiting rod (22); the center of the screw tail (3) and the branch (21) is provided with a cavity along the axial direction, the diameter of the cavity matches the diameter of the limiting rod (22); the limiting rod (22) of the screw head (1) and the branch (21) is embedded in the cavity of the adjacent branch (21) or the screw tail (3) to form a whole.

7. The injection molding screw structure of the injection molding machine according to claim 6, characterized in that: The threaded component comprises a limiting bolt (23); the limiting bolt (23) is radially arranged between the branch (21) and the screw tail (3); the end of the limiting bolt (23) extends into the limiting rod (22); the limiting bolt (23) is staggered and staggered from the screw rib part.

8. The injection molding screw structure of an injection molding machine according to claim 1, characterized in that: The threaded component comprises a limiting straight rod (25) and a limiting nut (26); the limiting straight rod (25) is fixedly connected to the center of the screw head (1); a cavity adapted to the limiting straight rod (25) is opened at the center of each branch (21); a plurality of branches (21) are sleeved on the outer surface of the limiting straight rod (25); the end of the limiting straight rod (25) extends to the screw tail (3) through the cavity of the branch (21); and the limiting nut (26) is threadedly connected to the end of the limiting straight rod (25) and is tightly attached to the screw tail (3).

9. The injection molding screw structure of the injection molding machine according to claim 8, characterized in that: A groove is radially formed on the end face of the tail end of the screw tail (3), a limiting straight rod (25) extends into the groove, and a limiting nut (26) is located in the groove and fits the inner wall of the groove.

10. The injection molding screw structure of an injection molding machine according to claim 8, characterized in that: A plurality of through holes (27) are radially opened inside the branch (21), and the through holes (27) are located at the periphery of the cavity of the branch (21).

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