Automobile bumper injection mold

Abstract

The invention belongs to the technical field of bumper molds, and particularly relates to an automobile bumper injection mold which comprises an air exhaust mechanism. The air exhaust mechanism comprises a telescopic part; a piston is connected into the exhaust hole in a sliding and sealing mode. A connecting rod is fixedly connected between the output end of the telescopic piece and the piston; an air hole I is formed in the piston; an isolation seat is fixedly connected into the bottom of the exhaust hole; an air hole II is formed in the isolation seat; the piston is driven by the telescopic piece to do reciprocating motion in the exhaust hole, when the piston moves upwards, negative pressure is generated between the piston and the isolation seat, air in plastic melt in a cavity can be sucked to the position between the piston and the isolation seat through the second air hole, and then when the piston moves downwards, the air between the piston and the isolation seat is compressed; air can be extruded upwards through the first air holes, air in the cavity is gradually sucked out of the mold, the compactness degree of plastic is improved, and the bubble content is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of bumper moulds, in particular to an injection mould for an automobile bumper. Background Art

[0002] As one of the most important protective parts of the car exterior, the car bumper is widely used in the front and rear ends of the car, mainly used to absorb the impact force during a collision and protect the body structure and the safety of the car owner. The injection mold is usually equipped with exhaust grooves, exhaust holes and other structures, and natural exhaust is used to reduce the air content in the raw materials. However, the mold cavity structure of the bumper is quite complex, the exhaust structure is difficult to design, the exhaust effect is poor, and the natural exhaust method is difficult to meet the production quality requirements.

[0003] A Chinese patent application CN113386310B discloses a stable injection mold for automobile bumpers, and the key points of its technical solution are: including a frame, a lifting assembly, a rotating assembly, a die assembly and a buffer assembly; the lifting assembly, the rotating assembly and the buffer assembly are arranged on the frame; the die assembly is arranged on the rotating assembly; the buffer assembly is located below the die assembly; and a vent valve is arranged on the upper mold and the lower mold. This technology sets a lifting assembly and a rotating assembly, uses a lifting seat to drive the mold plate to lift on the frame; uses a moving seat to drive the mold plate to rotate on the turntable, thereby increasing the movement form of the mold during the injection molding process, driving the mold to rotate, which is beneficial to improving the uniformity of the material in the mold, and thus improving the production quality of the material; by setting the die assembly, the die stability of the upper and lower molds on the mold plate is improved, and it is convenient to make the upper and lower molds rotate synchronously with the turntable in the pressed state.

[0004] However, the above technology often has the following defects: it uses the method of rotating and moving the mold as a whole to improve the uniformity of the material in the mold and discharge the air in the material to improve the injection molding quality. However, the weight and size of the automobile bumper injection mold are extremely large, weighing several tons or even dozens of tons and being several meters long. Such a huge device requires a lot of material and manpower when moving, and is prone to deformation and damage of the mold itself during the movement, thereby reducing the processing accuracy and service life of the mold.

[0005] To this end, the present invention provides an automobile bumper injection mold. Summary of the invention

[0006] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0007] The technical solution adopted by the present invention to solve the technical problem is as follows: the automobile bumper injection mold described in the present invention comprises a mold body, a cavity and a gate;

[0008] It also includes a group of evenly arranged exhaust holes; the exhaust holes are opened between the upper side of the mold body and the cavity; the exhaust holes are each provided with an exhaust mechanism; the exhaust mechanism is used to extract the air inside the plastic melt in the cavity;

[0009] The vacuum mechanism includes a telescopic part fixedly connected to the upper side of the mold body; a piston is slidably and sealably connected inside the exhaust hole; a hollow connecting rod is fixedly connected between the output end of the telescopic part and the piston; an air hole 1 is opened inside the piston, and the air hole 1 is aligned with the connecting rod; an air groove is opened at the bottom of the connecting rod; an isolation seat is fixedly connected to the bottom of the exhaust hole; an air hole 2 is opened inside the isolation seat; and one-way valves are provided inside both the air hole 1 and the air hole 2.

[0010] Preferably, a breathable steel insert is fixedly connected inside the exhaust hole below the isolation seat, and the breathable steel insert is flush with the inner surface of the cavity.

[0011] Preferably, an annular storage groove is provided on the upper side of the piston.

[0012] Preferably, an annular dirt collecting groove is provided on the lower side of the piston; a movable ring is connected to the inside of the dirt collecting groove in a sliding seal; a group of springs are evenly distributed between the movable ring and the dirt collecting groove; a group of bosses are evenly distributed on the lower side of the movable ring; adsorption holes are provided on the bosses and inside the movable ring; a group of release holes are evenly distributed between the dirt collecting groove and the storage groove; and one-way valves are provided inside the adsorption holes and the release holes.

[0013] Preferably, a pressure ring is fixedly connected to the lower side of the protruding column; the pressure ring is designed to be a hollow grid shape.

[0014] Preferably, a blocking cap is fixedly connected to the bottom of the storage slot at a position corresponding to the release hole; and a group of guide holes are evenly distributed on the bottom of the blocking cap.

[0015] Preferably, an annular blocking cover is provided inside the top of the storage tank; the blocking cover is connected to the storage tank via threads; and a group of through holes are evenly distributed on the surface of the blocking cover.

[0016] Preferably, a mounting plate is fixedly connected inside the through holes; a through slot is opened on one side of the mounting plate; a spring sheet is fixedly connected inside the through slot; an end of the spring sheet extends to the lower side of the mounting plate and there is a gap between the spring sheet and the mounting plate.

[0017] Preferably, an annular sink groove is provided at the upper edge of the isolation seat.

[0018] Preferably, a drainage plate is fixedly connected to the upper side of the isolation seat at a position corresponding to the second air hole; and a gap exists between the drainage plate and the upper side of the isolation seat.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1. The automobile bumper injection mold described in the present invention drives the piston to reciprocate inside the exhaust hole through a telescopic part. When the piston moves upward, negative pressure is generated between the piston and the isolation seat, and the air inside the plastic melt in the cavity can be sucked into the space between the piston and the isolation seat through the second air hole. Then, when the piston moves downward, the air between the piston and the isolation seat is compressed, and the air between the piston and the isolation seat can be squeezed upward through the first air hole, the connecting rod, and the air groove. Through multiple up and down movements of the piston, the air in the cavity can be gradually sucked to the outside of the mold, thereby improving the density of the plastic and reducing the bubble content.

[0021] 2. The automobile bumper injection mold described in the present invention programs multiple telescopic parts through a control system so that the movement stroke of the piston increases with the distance between it and the gate, that is, the farther away from the gate, the greater the movement stroke of the piston of the vacuum mechanism, and the greater the vacuum force, so that the plastic melt in the cavity has a tendency to diffuse and flow from the gate to the surrounding area, thereby improving the uniformity of the melt distribution. During the flow process, the melt fills the complex and narrow corners of the cavity and squeezes the bubbles therein, which can help the vacuum mechanism to extract the air outward, thereby improving the exhaust efficiency during bumper injection molding.

[0022] 3. The automobile bumper injection mold described in the present invention programs multiple telescopic parts through a control system, so that when adjacent vacuum mechanisms are in operation, the telescopic periods of the telescopic parts are opposite, and the pistons inside adjacent exhaust holes are controlled to move in opposite directions. The negative pressure is then used to cause the melt between adjacent exhaust holes in the cavity to continuously change its flow direction, so that the melts carrying bubbles are squeezed and rubbed against each other, promoting the release of bubbles between the melt gaps to the outside, and further facilitating the vacuum mechanism to suck the air. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] Figure 1 is a stereogram of the present invention;

[0025] Figure 2 It is a structural schematic diagram of the air extraction mechanism in the present invention;

[0026] Figure 3 It is a schematic diagram of the structure of the piston, the isolation seat and the breathable steel insert in the present invention;

[0027] Figure 4 It is a disassembly schematic diagram of the piston in the present invention;

[0028] Figure 5 yes Figure 4 A partial enlarged view of the middle part;

[0029] Figure 6is a partial cross-sectional view of the present invention;

[0030] Figure 7 yes Figure 6 A partial enlarged view of point B in the middle;

[0031] Figure 8 yes Figure 7 A partial enlarged view of point C in the middle;

[0032] Fig. 9 yes Figure 6 A partial enlarged view of point D in the middle.

[0033] In the figure: mold body 1, cavity 2, gate 3, vent hole 4, telescopic part 5, piston 6, connecting rod 7, air hole 1 8, air groove 9, isolation seat 10, air hole 2 11, breathable steel insert 12, storage groove 13, sewage collecting groove 14, movable ring 15, spring 16, adsorption hole 17, release hole 18, pressure ring 19, stop cap 20, guide hole 21, blocking cover 22, through hole 23, mounting plate 24, through groove 25, spring piece 26, sink groove 27, drainage plate 28. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0035] like Figures 1 to 9 As shown, the automobile bumper injection mold of the present invention comprises a mold body 1, a cavity 2 and a gate 3;

[0036] It also includes a group of evenly arranged exhaust holes 4; the exhaust holes 4 are opened between the upper side of the mold body 1 and the cavity 2; the exhaust holes 4 are each provided with an exhaust mechanism; the exhaust mechanism is used to suck the air inside the plastic melt in the cavity 2;

[0037] The vacuum mechanism includes a telescopic part 5 fixedly connected to the upper side of the mold body 1, and the telescopic part 5 can be a common telescopic cylinder, an electric push rod, etc.; a piston 6 is slidably and sealedly connected inside the exhaust hole 4; a hollow connecting rod 7 is fixedly connected between the output end of the telescopic part 5 and the piston 6; an air hole 1 8 is provided inside the piston 6, and the air hole 1 8 is aligned with the connecting rod 7; an air groove 9 is provided at the bottom of the connecting rod 7; an isolation seat 10 is fixedly connected to the bottom of the exhaust hole 4; an air hole 2 11 is provided inside the isolation seat 10; and both the air hole 1 8 and the air hole 2 11 are provided with a one-way valve.

[0038] The existing technology uses a method of rotating and moving the mold as a whole to improve the uniformity of the material in the mold and discharge the air in the material to improve the injection molding quality. However, the weight and size of the automobile bumper injection mold are extremely large, weighing several tons or even dozens of tons and being several meters long. Such a huge device requires a lot of material and manpower when moving, and is prone to deformation and damage of the mold itself during the movement, thereby reducing the processing accuracy and service life of the mold.

[0039] The present invention provides an exhaust mechanism at each exhaust hole 4. After the mold cavity 2 is filled with plastic melt, the gate 3 is closed, and the telescopic member 5 is used to drive the piston 6 to reciprocate inside the exhaust hole 4, and the piston 6 and the exhaust hole 4 are sealed. When the piston 6 moves upward, a negative pressure is generated between the piston 6 and the isolation seat 10. At this time, the one-way valve of the air hole 1 8 is closed, and the one-way valve of the air hole 2 11 is turned on. The air inside the plastic melt in the mold cavity 2 can be sucked between the piston 6 and the isolation seat 10 through the air hole 2 11. Then, when the piston 6 moves downward, the air between the piston 6 and the isolation seat 10 is compressed. At this time, the one-way valve of the air hole 1 8 is turned on, and the one-way valve of the air hole 2 11 is closed. The air between the piston 6 and the isolation seat 10 can be squeezed upward through the air hole 1 8, the connecting rod 7, and the air groove 9. Through the multiple up and down movements of the piston 6, the air in the mold cavity 2 can be gradually sucked to the outside of the mold, thereby improving the density of the plastic and reducing the bubble content.

[0040] It is worth mentioning that another embodiment of the vacuum mechanism of the present invention is: due to the influence of multiple factors such as melt viscosity, flow path, cavity 2 structure, etc., especially for complex injection molded parts such as automobile bumpers, the pressure distribution in the cavity 2 is usually uneven, the area close to the gate 3 has higher pressure and fewer bubbles, and the area far from the gate 3 has lower pressure and more bubbles. Therefore, the control system is used to program multiple telescopic parts 5 so that the movement stroke of the piston 6 increases with the distance between it and the gate 3, that is, the farther away from the gate 3, the greater the movement stroke of the piston 6 of the vacuum mechanism, and the greater the vacuum force, so that the plastic melt in the cavity 2 has a tendency to diffuse and flow from the gate 3 to the surrounding area, thereby improving the uniformity of the melt distribution. During the flow process, the melt fills the complex and narrow corners of the cavity 2 and squeezes the bubbles therein, which can help the vacuum mechanism to extract air outward and improve the exhaust efficiency during bumper injection molding.

[0041] It is worth mentioning that another implementation of the vacuum mechanism of the present invention is: multiple telescopic parts 5 are programmed through a control system so that when adjacent vacuum mechanisms are working, the telescopic periods of the telescopic parts 5 are opposite, and the pistons 6 inside the adjacent exhaust holes 4 are controlled to move in opposite directions. Then, negative pressure is used to cause the melt between adjacent exhaust holes 4 inside the cavity 2 to continuously change its flow direction, so that the melts carrying bubbles are squeezed and rubbed against each other, promoting the release of bubbles between the melt gaps to the outside, and further facilitating the vacuum mechanism to suck the air.

[0042] In addition, the piston 6 can scrape and rub the inner wall surface of the exhaust hole 4 during movement, thereby scraping off residual substances in the hole, such as mold lubricants, release agents, plastic additives, carbides, etc., to improve the permeability of the exhaust hole 4 and prevent blockage.

[0043] A permeable steel insert 12 (such as PM-35) is fixedly connected to the exhaust hole 4 below the isolation seat 10, and the permeable steel insert 12 is flush with the inner surface of the cavity 2. The microporous structure of the permeable steel allows gas to pass through, but the melt cannot pass through due to surface tension and viscosity, preventing the exhaust mechanism from extracting the melt upward when working.

[0044] An annular storage groove 13 is provided on the upper side of the piston 6 , and impurities scraped off the inner wall surface of the exhaust hole 4 by the upper side of the piston 6 can fall into the storage groove 13 for collection.

[0045] An annular dirt collecting groove 14 is provided at the lower side of the piston 6; a movable ring 15 is connected to the dirt collecting groove 14 in a sliding seal; a group of springs 16 are evenly distributed between the movable ring 15 and the dirt collecting groove 14; a group of bosses are evenly distributed at the lower side of the movable ring 15; adsorption holes 17 are provided inside the bosses and the movable ring 15; a group of release holes 18 are evenly distributed between the dirt collecting groove 14 and the storage groove 13; and one-way valves are provided inside the adsorption holes 17 and the release holes 18.

[0046] The impurities scraped off the inner wall surface of the exhaust hole 4 by the lower side of the piston 6 will fall on the surface of the isolation seat 10. As the piston 6 moves up and down inside the exhaust hole 4, the convex column can intermittently contact the upper side of the isolation seat 10 and squeeze the movable ring 15 into the sewage collecting tank 14. When the piston 6 moves away from the isolation seat 10, the spring 16 pushes the movable ring 15 to move downward inside the sewage collecting tank 14, thereby generating negative pressure inside the sewage collecting tank 14. At this time, the one-way valve of the adsorption hole 17 is turned on, and the one-way valve of the release hole 18 is closed, and the surface of the isolation seat 10 is enclosed by air. The impurities are sucked into the sewage collecting tank 14 through the adsorption hole 17, and when the piston 6 moves close to the isolation seat 10, the movable ring 15 moves upward again. At this time, the one-way valve of the adsorption hole 17 is closed, and the one-way valve of the release hole 18 is connected, so that the air in the sewage collecting tank 14 can carry the impurities and squeeze them into the storage tank 13 through the release hole 18, so as to continuously collect the impurities on the surface of the isolation seat 10, so that the impurities scraped off from the upper and lower sides of the piston 6 can be automatically recovered into the storage tank 13, which is convenient for subsequent centralized treatment.

[0047] A pressure ring 19 is fixedly connected to the lower side of the protruding column; the pressure ring 19 is designed to be a hollow grid shape. By providing the grid-shaped pressure ring 19, when the piston 6 moves downward, the pressure ring 19 can contact the isolation seat 10, ensuring that the adsorption hole 17 can adsorb impurities on the surface of the isolation seat 10 through the grid structure of the pressure ring 19, avoiding the problem of the adsorption hole 17 directly contacting the isolation seat 10 and being blocked.

[0048] The bottom of the storage tank 13 is fixedly connected with a stopper cap 20 at the position corresponding to the release hole 18; a group of guide holes 21 are evenly distributed at the bottom of the stopper cap 20. By setting the stopper cap 20, when the airflow carrying impurities enters the storage tank 13 through the release hole 18, it can be blocked by the stopper cap 20, and after impacting the inner wall of the stopper cap 20, the moving direction is changed and discharged toward the side wall of the storage tank 13 through the guide holes 21, thereby preventing the airflow from directly impacting upwards and blowing out the impurities collected in the storage tank 13.

[0049] An annular blocking cover 22 is disposed in the top of the storage tank 13 ; the blocking cover 22 is connected to the storage tank 13 via threads; and a group of through holes 23 are evenly distributed on the surface of the blocking cover 22 .

[0050] The through holes 23 are fixedly connected to the mounting plates 24; a through slot 25 is provided on one side of the mounting plate 24; a spring piece 26 is fixedly connected to the through slot 25; the end of the spring piece 26 extends to the lower side of the mounting plate 24 and there is a gap between the spring piece 26 and the mounting plate 24, and the spring piece 26 is in an inclined state.

[0051] The impurities on the inner wall surface of the exhaust hole 4 that are scraped off by the upper side of the piston 6 can pass through the through hole 23 and the gap between the spring piece 26 and the mounting plate 24 and enter the storage tank 13 downward. As the piston 6 moves up and down, the spring piece 26 continuously swings up and down and deforms under the action of inertia, which can promote the impurities to pass downward from the gap. When the impurities collected inside the storage tank 13 are impacted by the airflow, the impurities inside the storage tank 13 are difficult to escape out through the through hole 23 due to the overlap and obstruction between the inclined spring piece 26 and the mounting plate 24.

[0052] In order to clean the impurities, the piston 6 can be taken out from the exhaust hole 4 regularly, and then the blocking cover 22 can be unscrewed to pour out the impurities in the storage tank 13.

[0053] An annular sink 27 is provided at the upper edge of the isolation seat 10. Impurities scraped off the inner wall surface of the exhaust hole 4 by the lower side of the piston 6 can fall down along the hole wall into the sink 27, thereby increasing the concentration of impurities. After the piston 6 descends, the adsorption hole 17 is aligned with the sink 27, which facilitates the adsorption hole 17 to capture impurities.

[0054] A guide plate 28 is fixedly connected to the upper side of the isolation seat 10 at the position corresponding to the second air hole 11; there is a gap between the guide plate 28 and the upper side of the isolation seat 10. When the air sucked from the cavity 2 flows upward through the second air hole 11, it can impact the surface of the guide plate 28, and the guide plate 28 is used to guide the airflow, so that the airflow can diffuse to the surroundings along the narrow gap between the guide plate 28 and the isolation seat 10, thereby blowing the impurities scattered on the upper surface of the isolation seat 10 into the sink 27, further improving the subsequent collection efficiency of impurities.

[0055] The above-mentioned front, back, left, right, top and bottom are all based on the figures in the specification. Figure 1 As a benchmark, according to the person's observation perspective, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0056] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present invention.

[0057] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An automobile bumper injection mold, comprising a mold body (1), a mold cavity (2) and a gate (3); Features: It also comprises a group of evenly arranged exhaust holes (4); the exhaust holes (4) are opened between the upper side of the mold body (1) and the mold cavity (2); an exhaust mechanism is arranged inside the exhaust holes (4); the exhaust mechanism is used to suck the air inside the plastic melt in the mold cavity (2); The vacuum mechanism comprises a telescopic member (5) fixedly connected to the upper side of the mold body (1); a piston (6) is slidably and sealably connected inside the exhaust hole (4); a hollow connecting rod (7) is fixedly connected between the output end of the telescopic member (5) and the piston (6); an air hole (8) is provided inside the piston (6); an air groove (9) is provided at the bottom of the connecting rod (7); an isolation seat (10) is fixedly connected inside the bottom of the exhaust hole (4); an air hole (11) is provided inside the isolation seat (10); and both the air hole (8) and the air hole (11) are provided with a one-way valve.

2. The automobile bumper injection mold according to claim 1, characterized in that: A breathable steel insert (12) is fixedly connected to the inside of the exhaust hole (4) below the isolation seat (10), and the breathable steel insert (12) is flush with the inner surface of the cavity (2).

3. The automobile bumper injection mold according to claim 1, characterized in that: An annular storage groove (13) is provided on the upper side of the piston (6).

4. The automobile bumper injection mold according to claim 3, characterized in that: An annular dirt collecting groove (14) is provided at the lower side of the piston (6); a movable ring (15) is slidably sealed inside the dirt collecting groove (14); a group of springs (16) are evenly distributed between the movable ring (15) and the dirt collecting groove (14); a group of convex columns are evenly distributed at the lower side of the movable ring (15); adsorption holes (17) are provided inside the convex columns and the movable ring (15); a group of release holes (18) are evenly distributed between the dirt collecting groove (14) and the storage groove (13); and one-way valves are provided inside the adsorption holes (17) and the release holes (18).

5. The automobile bumper injection mold according to claim 4, characterized in that: A pressing ring (19) is fixedly connected to the lower side of the protruding column; the pressing ring (19) is designed to be in a hollow grid shape.

6. The automobile bumper injection mold according to claim 4, characterized in that: A blocking cap (20) is fixedly connected to the bottom of the storage groove (13) at a position corresponding to the release hole (18); a group of guide holes (21) are evenly distributed on the bottom of the blocking cap (20).

7. The automobile bumper injection mold according to claim 4, characterized in that: An annular blocking cover (22) is arranged inside the top of the storage tank (13); the blocking cover (22) and the storage tank (13) are connected via threads; and a group of through holes (23) are evenly distributed on the surface of the blocking cover (22).

8. The automobile bumper injection mold according to claim 7, characterized in that: The through holes (23) are fixedly connected to the inside of the mounting plates (24); a through slot (25) is provided on one side of the mounting plates (24); a spring sheet (26) is fixedly connected to the inside of the through slot (25); an end of the spring sheet (26) extends to the lower side of the mounting plates (24) and a gap exists between the spring sheet (26) and the mounting plates (24).

9. The automobile bumper injection mold according to claim 4, characterized in that: An annular sink groove (27) is provided at the upper edge of the isolation seat (10).

10. The automobile bumper injection mold according to claim 9, characterized in that: A drainage sheet (28) is fixedly connected to the upper side of the isolation seat (10) at a position corresponding to the second air hole (11); a gap exists between the drainage sheet (28) and the upper side of the isolation seat (10).

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