CN113043547A

CN113043547A - Forming die of pump body

Info

Publication number: CN113043547A
Application number: CN202110417375.8A
Authority: CN
Inventors: 汪卫平; 唐子一; 李建新; 吴海洋; 汪渌; 汪洁; 王子骏
Original assignee: Anhui Kaite Pump Co ltd
Current assignee: Anhui Kaite Pump Co ltd
Priority date: 2021-04-19
Filing date: 2021-04-19
Publication date: 2021-06-29

Abstract

The invention provides a pump body forming die, which comprises a pump body forming external die and a core die, wherein the forming external die comprises a first external die and a second external die, a parting surface formed by a joint surface of the first external die and the second external die is vertical to the axial direction of a pump body and passes through a symmetrical surface where a pipe core of a liquid outlet pipe of the pump body is positioned, the inner wall of a forming cavity of the second external die is consistent with the outer peripheral wall of the axial front section of the pump body, an annular core die is arranged in the inner cavity of the first external die, a step core column is arranged in the middle of the annular core die, the outer shaft of a small-diameter core column at the front section of the step core column is consistent with the pipe cavity of a liquid inlet pipe of the pump body, the outer peripheral surfaces of a disc core column at the rear end of the small-diameter.

Description

Forming die of pump body

Technical Field

The invention relates to a forming die, in particular to a forming die of a pump body.

Background

Centrifugal pumping media are very common in industrial and agricultural production, but the requirements of media conveyed in special industries on the material and the structure of a pumping flow component are very strict. In some fields, a medium with special components needs to be pumped, for example, when a high-grade cold-rolled automobile plate or a high-end silicon steel plate is produced, a pickling solution needs to be conveyed by a pump, the components of the pickling solution are 20% of mixed acid of concentrated hydrochloric acid or hydrofluoric acid and the like, the temperature is 80-100 ℃, the flow rate of the conveying medium reaches 250m3/h, the lift is higher than 100m, a metal pump made of common materials cannot be used, a few metal pumps made of special materials can be used, but the metal pump has no practical use value due to short service life and high cost. Plastic pumps are commonly used.

Therefore, although the plastic centrifugal pump widens the application range compared with a centrifugal pump made of metal, the plastic centrifugal pump is formed, particularly an impeller and a pump body which are key parts, the applicant applies a forming die named as an impeller (with the patent number being ZL201820849677.6), and the problem of difficult demoulding is solved by reasonably arranging a core die. However, due to the unique shape of the pump body, the core mold of the liquid cavity of the pump body cannot be formed by injection molding by adopting a similar scheme of impeller forming.

In the prior art, "medical waste treatment equipment and a manufacturing method thereof" (publication number CN 108099111 a, hereinafter referred to as document 1) substantially disclose a related scheme for molding a medical infusion pump body by using an injection mold, in document 1, a characteristic part of a demolding difficulty formed by a liquid medicine inlet a, a first outlet B, a second outlet C and a third outlet D is designed, taking B characteristic as an example, except that B1 is a basic cylinder characteristic, three characteristics of B2, B3 and B4 exist to influence demolding, B2 is a square hole located on an a1 cylinder, B3 is an internal thread located in a B1 cylinder, and B4 is a helical tooth, so that it is very critical to solve the problems that the molding and die supporting of the internal thread B3 located in the B1 cylinder are very critical, and the molding of the internal thread can be realized by using a rotating threaded rod core and the demolding can be realized by rotating the threaded rod core.

The structure of the pump body a is as shown in fig. 1a, 1B, 1c, the pump cavity for accommodating the impeller includes an overall cylindrical cavity a1, a through hole is provided in the middle of a rear end cover (not shown) assembled on the pump body for the impeller shaft to pass through and to be supported by a bearing, a transition groove cavity a2 which is in forward-extending connection with the pipe wall of the liquid outlet pipe cavity B is provided on the peripheral wall of the cylindrical cavity a1, because the radial size of the transition groove cavity a2 is larger than the size of the rear end port of the pump body, the demolding of the mold core for molding the region of the transition groove cavity a2 is particularly difficult, that is, the transition groove cavity a2 cannot be molded and demolded by using the scheme of the threaded core rod for molding the internal thread B; in addition, the core mold stripping for forming the curved section at the junction of the transition cavity a2 and the outlet cavity B in the pump body is also addressed.

Disclosure of Invention

The invention aims to provide a pump body forming die, which realizes convenient demoulding of the pump body forming die and an impeller cavity of a formed pump body.

In order to achieve the purpose, the invention adopts the following technical scheme that the forming die of the pump body comprises a pump body forming external die and a core die, and is characterized in that: the forming outer mold comprises a first outer mold and a second outer mold, a parting surface formed by the joint surfaces of the first outer mold and the second outer mold is perpendicular to the axial direction of the pump body and passes through a symmetrical surface where a pipe core of a liquid outlet pipe of the pump body is located, the inner wall of a forming cavity of the second outer mold conforms to the outer peripheral wall of the axial front section of the pump body, an annular core mold is arranged in the inner cavity of the first outer mold, a step core column is arranged in the middle of the annular core mold, an outer shaft of a small-diameter core column at the front section of the step core column conforms to the pipe cavity of a liquid inlet pipe of the pump body, the outer peripheral surfaces of a disc core column at the rear end of the small-diameter core column and the annular core mold conform.

In the scheme, the molded surfaces of the annular core mold and the step core column facing the inner cavities of the first outer mold and the second outer mold are consistent with the shapes of the inner cavity of the pump body and the inner peripheral wall of the liquid inlet pipe and are used for molding. In view of the fact that the radial large-size disc core column can deviate from the hole area in the middle of the annular core column when the step core column axially displaces, and the circumferential segmented structure of the annular core column is added, part of the arc-shaped unit sections are contracted and closed radially inwards in advance, and then the rest of the arc-shaped unit sections are contracted and closed radially, so that the radial flange part on the annular core column is separated from the notch area of the transition groove cavity of the formed pump body in the radial direction, and the core column and the impeller cavity of the formed pump body can be separated through axial displacement at the moment, and accordingly demolding is achieved.

Drawings

FIGS. 1a, 1b, 1c are structural diagrams of a pump body to be injection-molded, wherein 1b, 1c are a left side view and a K-K cross-sectional view of FIG. 1a, respectively;

FIGS. 2 and 3 are schematic perspective views of the mold closing and opening states of the present invention;

FIGS. 4 to 11 are schematic perspective views of the demolding process according to the present invention;

fig. 12 is a front view of a mandrel of the present invention.

Detailed Description

In order to facilitate the understanding of the invention, it is necessary to carry out a brief supplementary description of the basic shape of the pump body a to be injected. As shown in fig. 1a, 1b and 1c, the distance between each point of the transition groove cavity a2 a21, a22, a23, a24 and a25 and the axis core is gradually increased, the size from the part to be molded to the axis core of the pump body a is larger than the diameter of the cavity at the position of the inner cavity A3, so that the mold core for molding the region of the transition groove cavity a2 cannot be demolded in a conventional direct axial movement mode, which is the technical problem to be solved by the invention. It should be noted that the forming of the outlet portion of the pump body a is solved by the application filed by the applicant, and will not be described herein.

In the following description, the position is defined as forward or backward, and forward means forward of the liquid pipe C in the axial direction, i.e., the direction of the impeller shaft, and backward of the liquid pipe C on the side away from the impeller shaft.

A pump body forming die comprises a pump body forming external die and a core die, wherein the forming external die comprises a first external die 10 and a second external die 20, the first external die, the parting plane formed by the joint surfaces of the two

outer molds

10 and 20 is vertical to the axial direction of the pump body A and passes through the symmetrical plane of the pipe core of the liquid outlet pipe B of the pump body A, the inner wall of the forming cavity of the second outer mold 20 conforms to the outer peripheral wall of the axial front section of the pump body A, the annular core mold 30 is arranged in the inner cavity of the first outer mold 10, the middle part of the annular core mold 30 is provided with a step core column 40, the outer shaft body of a small-diameter core column 41 at the front section of the step core column 40 conforms to the pipe cavity of the liquid inlet pipe C of the pump body A, the outer peripheral surfaces of a disc core column 42 at the rear end of the small-diameter core column 41 and the annular core mold 30 conform to the inner wall of the cavity of the pump body A at the rear section of the.

Firstly, selecting a parting surface of a forming die of the pump body A, according to the scheme, the parting surfaces of the first and second

outer dies

10 and 20 are vertical to the axial direction of the pump body A and pass through a symmetrical surface where a tube core of a liquid outlet pipe B of the pump is positioned, namely a plane of a symmetrical line of a figure 1a, namely a K-K plane in the figure, so that the forming of the outer peripheral surface of the pump body A can be realized, and the parting at the A-A plane is beneficial to the demoulding of the outer peripheral wall of the liquid outlet pipe cavity B and the first and second

outer dies

10 and 20; furthermore, an annular core mold 30 is arranged in the inner cavity of the first outer mold 10, a step core column 40 is arranged in the middle of the annular core mold 30, the step core column 40 is firstly set to be of an axial displacement structure, when the step core column is axially displaced, the step core column can be conveniently separated from a liquid inlet pipe C of the pump body A and is exposed out of a hole area in the middle of the annular core mold 30, and by combining a sectional structure of the annular core mold 30, arc-shaped section units of part of the annular core mold 30 are firstly radially contracted and closed, arc-shaped unit sections of the other part of the annular core mold 30 can be subsequently closed and contracted, so that the outer area of the annular core mold 30 in an avoiding and closing state of the transition groove cavity A2 area of the annular core mold 30 and the pump body A is positioned in the cavity diameter range of the inner cavity A3.

Based on the specific specification and size of the pump body a, the annular core mold 30 is divided into 4-8 unit segments along the circumferential direction, that is, the annular core mold 30 includes a forward sector core mold unit 31, and a reverse sector core mold unit 32 is disposed between the two forward sector core mold units 31. It should be noted here that the "regular sector" in the regular sector core mold unit 31 is the meaning of a sector in the conventional sense, and the contour of the sector area refers to the contour shape of the projection of the sector area on the surface perpendicular to the axial direction, the outer arc length of the peripheral contour is longer than the length of the inner arc length, and the extension lines of the two ends intersect at the center of the axis of the cylindrical surface or the circumference, or the intersection of the extension surfaces of the two end surfaces is located on the same side as the curvature axis with respect to the sector area of the sector arc; accordingly, it can be easily understood that the inverse fan-shaped core mold unit 32 includes two cases, as shown in fig. 12, in which end surfaces of both ends are parallel and simultaneously parallel to a certain radial direction, and in which end surfaces of both ends are arranged at an included angle and an intersection is disposed on both sides of the arc-shaped region with the curvature axis core. The unit segments constituting the annular core mold 30 are divided into the forward sector core mold unit 31 and the reverse sector core mold unit 32 and arranged alternately with each other so that the reverse sector core mold unit 32 can be moved in the radial direction in advance, thus providing a displacement space for the movement of the forward sector core mold unit 31.

The annular core mold 30 is divided into even-numbered unit segments of 4, 6, and 8 in the circumferential direction, and the number of the forward sector core mold units 31 and the reverse sector core mold units 32 is equal. By segmenting according to the above scheme, the forward sector core mold unit 31 and the reverse sector core mold unit 32 can be ensured to be folded in a smaller overall circular-square-shaped area without excessively large displacement of the forward sector core mold unit 31 and the reverse sector core mold unit 32 in the radial direction, so that the demolding efficiency can be improved.

The positive sector core die unit 31 is connected with a positive sector core die arc-shaped plate 311, the positive sector core die arc-shaped plate 311 extends towards the rear end of the step core column 40 and is connected with a first cylinder 50 at the end, the reverse sector core die unit 32 is connected with a reverse sector core die arc-shaped plate 321, the reverse sector core die arc-shaped plate 321 extends towards the rear end of the step core column 40 and is connected with a second cylinder 60 at the end, and the extension and retraction directions of the first cylinder 50 and the second cylinder 60 are perpendicular to the axial core direction of the step core column 40.

The above scheme is to ensure the realization of the radial displacement of each segment of the forward and reverse fan-shaped

core mold units

31 and 32, and the arrangement of the forward and reverse fan-shaped core

mold arc plates

311 and 321 ensures the integrity of the molding surface formed by the forward and reverse fan-shaped

core mold units

31 and 32, and provides a power intervention portion to realize the radial displacement of the forward and reverse fan-shaped

core mold units

31 and 32.

The first outer die 10 comprises a front outer die 11 and a rear outer die 12, the annular core die 30 is connected with the front outer die 11, the step core column 40 is arranged on the rear outer die 12, a third cylinder 70 is arranged between the front outer die 11 and the rear outer die 12, and the third cylinder 70 drives the front outer die 11 and the rear outer die 12 to move close to or separate from each other along a direction parallel to the step core column 40. Here the back overmold 12 itself has no molding surfaces, with the stepped stem 40 provided thereon having molding surfaces, and thus the back overmold 12 may also be understood as an additional support or seat for achieving axial displacement of the stepped stem 40. The third cylinder 70 is operated so that the step core 40 can be in a fitting state where they are fitted to each other to form a molding surface with respect to the ring core mold 30, or can be separated from each other to provide a space for demolding.

The piston rods of the first and

second cylinders

50, 60 are matched with the front outer die 11 through anti-twist slide blocks and chutes. In this way, since the posture of each of the normal and reverse

core mold units

31, 32 is not changed and only the position thereof with respect to the axial core of the step core column 40 is changed, the normal and reverse

core mold units

31, 32 are translationally displaced in the radial direction with respect to the axial core of the step core column 40 during the radial displacement thereof. In the specific implementation, the upper side of the front outer mold 11 is provided with a sliding chute or hole 111, and the upper square

section sliding blocks

51 and 61 on the piston rods of the first and

second cylinders

50 and 60 form anti-twisting guiding fit with the sliding chute or hole.

Fig. 10 and 11 show the three-dimensional structure of the annular core mold 30 and the stepped core column 40 at the back or rear visible range of the front outer mold 11, and the first and

second cylinders

50 and 60 are arranged at intervals in the axial direction of the stepped core column 40. As shown in the drawings, the surfaces of the first and

second cylinders

50 and 60 are spaced at an appropriate interval in the axial direction, so that the interference phenomenon does not occur when the forward and reverse

core mold units

31 and 32 are folded, and the folding is ensured to be as small as possible in the area space. As can be seen from the figure, the slide block 61 on the second cylinder 60 and the positive sector core mold arc plate 311 are located at positions that are mutually receded.

More preferably, the regular sector core mold units 31 are provided with equal arc lengths, the reverse sector core mold units 32 are provided with equal arc lengths, and the arc length of the regular sector core mold unit 31 is larger than the arc length of the reverse sector core mold unit 32. This is also for minimizing the space occupied by the forward and reverse

core mold units

31 and 32 after they are collapsed.

Referring to fig. 9 and 10, the first outer mold 10 is provided with two push rods 80, the push rods 80 are symmetrically arranged, the rod length direction of the push rods 80 is parallel to the axial direction of the pump body a and is displaced along the rod length direction thereof, and the push rods 80 are located in the region between the inner cavity of the first outer mold 10 and the radially displaced and furled annular core mold 30. The function of the push rod 80 is to ensure that when the first outer die 10 is demolded from the molded pump body a, the push rod 80 abuts against the molded pump body a to realize the demolding and separating process.

Claims

1. The utility model provides a forming die of pump body, includes pump body shaping external mold and mandrel, its characterized in that: the molding outer die comprises a first outer die and a second outer die (10, 20), wherein the first outer die, the parting plane formed by the joint surfaces of the two outer molds (10 and 20) is vertical to the axial direction of the pump body (A) and passes through the symmetrical plane of the pipe core of the liquid outlet pipe (B) of the pump body (A), the inner wall of the forming cavity of the second outer mold (20) is consistent with the outer peripheral wall of the axial front section of the pump body (A), an annular core mold (30) is arranged in the inner cavity of the first outer mold (10), a step core column (40) is arranged in the middle of the annular core mold (30), the outer shaft body of a small-diameter column core (41) at the front section of the step core column (40) is consistent with the pipe cavity of the liquid inlet pipe (C) of the pump body (A), the disc core column (42) at the rear end of the small-diameter column core (41) and the outer peripheral surface of the annular core mold (30) are consistent with the inner wall of the cavity of the pump body (A) at the rear section of the liquid inlet pipe (C).

2. The forming die for a pump body according to claim 1, wherein: the annular core mold (30) is divided into 4-8 unit sections along the circumferential direction, the annular core mold (30) comprises a positive fan-shaped core mold unit (31), and a reverse fan-shaped core mold unit (32) is arranged between the two positive fan-shaped core mold units (31).

3. The forming die for a pump body according to claim 1 or 2, characterized in that: the annular core mold (30) is divided into 4, 6 and 8 units of even number along the circumferential direction, and the number of the positive sector core mold units (31) and the reverse sector core mold units (32) is equal.

4. The forming die for a pump body according to claim 2, wherein: positive fan-shaped mandrel unit (31) be connected with positive fan-shaped mandrel arc (311), positive fan-shaped mandrel arc (311) extend and end connection has first cylinder (50) to the rear end of step stem (40), anti-fan-shaped mandrel unit (32) are connected with anti-fan-shaped mandrel arc (321), anti-fan-shaped mandrel arc (321) extend and end connection has second cylinder (60) to the rear end of step stem (40), the flexible direction of first, two cylinders (50, 60) be the axle core direction of perpendicular to step stem (40).

5. The forming die for a pump body according to claim 1 or 2, characterized in that: the first outer die (10) comprises a front outer die (11) and a rear outer die (12), the annular core die (30) is connected with the front outer die (11), the step core column (40) is arranged on the rear outer die (12), a third air cylinder (70) is arranged between the front outer die (11) and the rear outer die (12), and the third air cylinder (70) drives the front outer die (11) and the rear outer die (12) to move close to or separate from each other along the direction parallel to the step core column (40).

6. The forming die for a pump body according to claim 1 or 2, characterized in that: the piston rods of the first and second cylinders (50, 60) are matched with the front outer die (11) through anti-twist slide blocks and chutes.

7. The pump body molding die according to claim 4, wherein: the first and second cylinders (50, 60) are arranged at intervals in the axial direction of the stepped stem (40).

8. The pump body molding die according to claim 4, wherein: the positive sector core mold units (31) are arranged with equal arc length, the reverse sector core mold units (32) are arranged with equal arc length, and the arc length of the positive sector core mold units (31) is larger than that of the reverse sector core mold units (32).

9. The forming die for a pump body according to claim 1, wherein: the first outer die (10) is provided with two push rods (80), the rod length direction of the push rods (80) is parallel to the axial direction of the pump body (A) and moves along the rod length direction of the pump body, and the push rods (80) are positioned in an area between the inner cavity of the first outer die (10) and the annular core die (30) which moves in a furled shape in the radial direction.