Improved ejection structure of automobile rear bumper injection mold

Abstract

The utility model discloses an improved ejection structure of an automobile rear bumper injection mold. Comprising a straight ejection block, a transverse ejector pin, a vertical sliding rail, a sliding groove and an ejection head, wherein the transverse ejector pin is transversely and movably arranged on the straight ejection block relative to the ejection direction of the straight ejection block; the vertical sliding rail is located on the transverse side of the straight ejection block and is fixedly arranged; the sliding groove is formed in the vertical sliding rail; the guide head is arranged at the rear end of the transverse ejector pin and is in sliding fit connection with the sliding groove in the vertical sliding rail; the sliding groove in the vertical sliding rail integrally deflects by a certain angle relative to the ejection direction of the straight ejection block, and the deflection direction enables the front end of the sliding groove in the ejection direction to be closer to the transverse distance between the rear end of the sliding groove in the ejection direction and the upside-down part on the automobile rear bumper relative to the rear end of the sliding groove in the ejection direction. The inclined top ejection mechanism can overcome the defects of an existing inclined top ejection mechanism of the automobile rear bumper injection mold, ejection block marks are prevented from being generated on the surface of a product, and the appearance quality of the product after injection molding of the automobile rear bumper is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molds, in particular to an improved ejection structure of an injection mold for a rear bumper of an automobile. Background Art

[0002] The rear bumper of an automobile is an injection molded part. An undercut structure is arranged on the rear bumper of the automobile at a position close to the rear wheel of the automobile. Figure 8 The invention is a schematic diagram of an injection mold for a rear bumper of an automobile in the prior art that adopts an inclined ejection mechanism. After the rear bumper of the automobile is injected, the undercut part is disengaged by the inclined ejection block of the inclined ejection mechanism.

[0003] The disadvantage of the above-mentioned injection mold for the rear bumper of the automobile is that the inclined top will elastically shift up and down due to the change of pressure during the injection molding process, resulting in a top block mark at point A on the product surface, thereby affecting the appearance quality of the product. Utility Model Content

[0004] In order to solve the above problems, the utility model proposes an improved ejection structure of the automobile rear bumper injection mold, which aims to overcome the defects of the existing automobile rear bumper injection mold inclined ejection mechanism, avoid the ejection block mark on the product surface, and improve the appearance quality of the automobile rear bumper after injection molding. The specific technical solution is as follows:

[0005] The improved ejection structure of an injection mold for a rear bumper of an automobile comprises a straight ejector block arranged on a movable mold of the injection mold for the rear bumper of the automobile, a transverse ejector pin arranged on the straight ejector block for transverse movement relative to the ejection direction of the straight ejector block, a vertical slide rail located on one side of the straight ejector block and fixedly arranged, a slide groove arranged on the vertical slide rail, a top head arranged at the front end of the transverse ejector pin for supporting an undercut portion on the rear bumper of the automobile, and a guide head arranged at the rear end of the transverse ejector pin and connected to the slide groove on the vertical slide rail for sliding cooperation; the slide groove on the vertical slide rail is deflected by a certain angle relative to the ejection direction of the straight ejector block as a whole, and the deflection direction is such that the front end of the slide groove in the ejection direction is closer to the undercut portion on the rear bumper of the automobile than the rear end of the slide groove in the ejection direction.

[0006] Preferably, the slide groove on the vertical slide rail is a three-section slide groove, and the three-section slide groove includes a front slide groove, a middle slide groove and a rear slide groove connected in sequence; wherein, the front slide groove and the rear slide groove are parallel to the ejection direction of the straight top block, and the front slide groove is closer to the undercut part on the rear bumper of the automobile than the rear slide groove, and the middle slide groove is an oblique slide groove that is transitionally connected between the front slide groove and the rear slide groove.

[0007] In the utility model, the undercut part on the rear bumper of the automobile comprises an undercut cantilever piece inclined toward one side of the straight top block, and an arc-shaped protrusion arranged at the cantilever end of the undercut cantilever piece and facing one side of the straight top block; the front end of the transverse ejector pin is provided with an arc-shaped groove adapted to the half arc-shaped protrusion on the cantilever end near the top end.

[0008] Preferably, the lateral moving direction of the lateral ejector pin is perpendicular to the inverted cantilever piece.

[0009] In the utility model, the number of the transverse ejector pins is a pair and they are arranged parallel to each other and at intervals.

[0010] In the utility model, a pair of slide grooves slidably matched with the guide heads on a pair of transverse ejector pins are correspondingly arranged on the front and rear sides of the vertical slide rail.

[0011] In the utility model, a pair of straight top push rods are connected to the straight top push block.

[0012] In the utility model, a sliding sleeve is arranged on the straight ejector block, and the rear outer circle of the transverse ejector pin is movably arranged on the sliding sleeve.

[0013] Preferably, a core shrinking assembly for facilitating the removal of parts during demolding is also provided on the straight top block, the core shrinking assembly includes a core shrinking mounting block provided on the straight top block, a telescopic core head provided on one side of the core shrinking mounting block, and a connecting screw provided on the other side of the core shrinking mounting block, the threaded section of the connecting screw passes through the through hole on the core shrinking mounting block and is threadedly connected with the telescopic core head, a compression spring is provided between the screw head of the connecting screw and the core shrinking mounting block, the outer circle of the telescopic core head is movably provided in the core shrinking mounting hole of the straight top block, and the front end face of the telescopic core head is flush with the cavity surface of the straight top block.

[0014] Preferably, after the telescopic core head is threadedly connected to the threaded section of the connecting screw, circumferential anti-rotation fixation is also achieved through pins.

[0015] Preferably, the front end surface of the telescopic core head is provided with a corrugated groove for increasing the contact area.

[0016] The beneficial effects of the utility model are:

[0017] First, the utility model provides an improved ejection structure of an automobile rear bumper injection mold, a specially designed straight ejection plus lateral ejection structure, and the lateral ejector can realize lateral ejection movement under the action of a vertical slide rail, so that the undercut cantilever piece is deformed, thereby realizing the smooth disengagement of the undercut part of the automobile rear bumper after injection molding.

[0018] Secondly, the utility model provides an improved ejection structure for an automobile rear bumper injection mold, which adopts a straight ejection block to cover the product area without a splicing line, thereby overcoming the ejection block mark caused by the elastic up and down displacement of the inclined ejection block in the traditional inclined ejection structure when the injection pressure changes, thereby improving the appearance quality of the automobile rear bumper injection molded product. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of an improved ejection structure of an injection mold for a rear bumper of an automobile according to the utility model;

[0020] Figure 2 yes Figure 1 A schematic diagram of the structure of the vertical slide rail in FIG.

[0021] Figure 3 Yes Figure 1 The schematic diagram of the structure of the car after the rear bumper is removed;

[0022] Figure 4 yes Figure 1 A schematic diagram of the structure of the lateral ejector part;

[0023] Figure 5 yes Figure 1 A schematic diagram of the structure of the core shrinking component;

[0024] Figure 6 It is a structural schematic diagram of an arc groove provided on the top of a transverse ejector pin to match the arc protrusion on the undercut cantilever piece of the rear bumper of an automobile;

[0025] Figure 7 It is a schematic diagram of the change in the position of the lateral ejector pin and the change in the deformation state of the undercut cantilever piece during the ejection process of the straight ejector block;

[0026] Figure 8 The invention is a structural schematic diagram of an automobile rear bumper injection mold in the prior art which adopts an inclined top block.

[0027] In the figure: 1. automobile rear bumper (partial view), 2. straight ejector block, 3. horizontal ejector pin, 4. vertical slide rail, 5. slide groove, 6. undercut part, 7. ejector head, 8. guide head, 9. front slide groove, 10. middle slide groove, 11. rear slide groove, 12. undercut cantilever piece, 13. arc-shaped protrusion, 14. arc-shaped groove, 15. straight ejector rod, 16. sliding sleeve, 17. core shrinking assembly, 18. core shrinking mounting block, 19. telescopic core head, 20. connecting screw, 21. compression spring, 22. core shrinking mounting hole, 23. pin, 24. corrugated groove, 25. inclined ejector block. DETAILED DESCRIPTION

[0028] The following is a further description of the specific implementation of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0029] like Figures 1 to 8 The utility model is shown as an embodiment of an improved ejection structure of an injection mold for a rear bumper of an automobile, comprising a straight ejector block 2 arranged on a movable mold of an injection mold for a rear bumper of an automobile, a transverse ejector pin 3 arranged on the straight ejector block 2 for transverse movement relative to the ejection direction of the straight ejector block 2, a vertical slide rail 4 located on one side of the straight ejector block 2 and fixedly arranged, a slide groove 5 arranged on the vertical slide rail 4, a top head 7 arranged at the front end of the transverse ejector pin 3 for supporting an undercut portion 6 on the rear bumper of the automobile, and a guide head 8 arranged at the rear end of the transverse ejector pin 3 and connected to the slide groove 5 on the vertical slide rail 4 for sliding cooperation; the slide groove 5 on the vertical slide rail 4 is deflected by a certain angle relative to the ejection direction of the straight ejector block 2 as a whole, and the deflection direction is such that the front end of the slide groove 5 in the ejection direction is closer to the undercut portion 6 on the rear bumper of the automobile than the rear end of the slide groove 5 in the ejection direction.

[0030] Preferably, the slide groove 5 on the vertical slide rail 4 is a three-section slide groove 5, and the three-section slide groove 5 includes a front slide groove 9, a middle slide groove 10 and a rear slide groove 11 connected in sequence; wherein, the front slide groove 9 and the rear slide groove 11 are parallel to the ejection direction of the straight top ejector block 2, and the front slide groove 9 is closer to the undercut part 6 on the rear bumper 1 of the automobile than the rear slide groove 11 in lateral distance, and the middle slide groove 10 is a skewed slide groove transitionally connected between the front slide groove 9 and the rear slide groove 11.

[0031] In this embodiment, the undercut portion 6 on the rear bumper 1 of the automobile includes an undercut cantilever piece 12 inclined toward one side of the straight top block 2, and an arc-shaped protrusion 13 arranged at the cantilever end of the undercut cantilever piece 12 and facing one side of the straight top block 2; the front end of the transverse ejector pin 3 is provided with an arc-shaped groove 14 adapted to the half arc-shaped protrusion 13 on the cantilever end near the top end.

[0032] Preferably, the lateral moving direction of the lateral ejector pin 3 is perpendicular to the inverted cantilever piece 12 .

[0033] In this embodiment, the transverse ejector pins 3 are in a pair and are arranged parallel to each other and spaced apart.

[0034] In this embodiment, a pair of slide grooves 5 slidably matched with the guides 8 on the pair of transverse ejector pins 3 are correspondingly provided on the front and rear sides of the vertical slide rail 4 .

[0035] In this embodiment, a pair of straight top push rods 15 are connected to the straight top push block 2 .

[0036] In this embodiment, a sliding sleeve 16 is provided on the straight ejector block 2 , and the rear outer circle of the transverse ejector pin 3 is movably provided on the sliding sleeve 16 .

[0037] Preferably, a core shrinking assembly 17 for facilitating the removal of parts during demolding is also provided on the straight top top block 2, the core shrinking assembly 17 includes a core shrinking mounting block 18 arranged on the straight top top block 2, a telescopic core head 19 arranged on one side of the core shrinking mounting block 18, and a connecting screw 20 arranged on the other side of the core shrinking mounting block 18, the threaded section of the connecting screw 20 passes through the through hole on the core shrinking mounting block 18 and is threadedly connected with the telescopic core head 19, a compression spring 21 is provided between the screw head of the connecting screw 20 and the core shrinking mounting block 18, the outer circle movement of the telescopic core head 19 is arranged in the core shrinking mounting hole 22 of the straight top top block 2, and the front end face of the telescopic core head 19 is flush with the cavity surface of the straight top top block 2.

[0038] Preferably, after the telescopic core head 19 is threadedly connected to the threaded section of the connecting screw 20 , circumferential anti-rotation fixation is also achieved through a pin 23 .

[0039] Preferably, the front end surface of the telescopic core head 19 is provided with a corrugated groove 24 for increasing the contact area.

[0040] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An improved ejection structure of an injection mold for a rear bumper of an automobile, characterized in that: The invention comprises a straight ejector block arranged on a movable mold of an injection mold for a rear bumper of an automobile, a transverse ejector pin arranged on the straight ejector block for transverse movement relative to the ejection direction of the straight ejector block, a vertical slide rail located on one lateral side of the straight ejector block and fixedly arranged, a slide groove arranged on the vertical slide rail, a top head arranged at the front end of the transverse ejector pin for supporting an undercut part on the rear bumper of the automobile, and a guide head arranged at the rear end of the transverse ejector pin and connected with the slide groove on the vertical slide rail for sliding cooperation; the slide groove on the vertical slide rail is deflected by a certain angle relative to the ejection direction of the straight ejector block as a whole, and the deflection direction is such that the front end of the slide groove in the ejection direction is closer to the undercut part on the rear bumper of the automobile than the rear end of the slide groove in the ejection direction.

2. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 1, characterized in that: The slide groove on the vertical slide rail is a three-section slide groove, which includes a front slide groove, a middle slide groove and a rear slide groove connected in sequence; wherein the front slide groove and the rear slide groove are parallel to the ejection direction of the straight top ejector block, and the front slide groove is closer to the undercut part on the rear bumper of the automobile than the rear slide groove in lateral distance, and the middle slide groove is an oblique slide groove transitionally connected between the front slide groove and the rear slide groove.

3. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 1, characterized in that: The undercut part on the rear bumper of the automobile comprises an undercut cantilever piece inclined toward one side of the straight top block, and an arc-shaped protrusion arranged at the cantilever end of the undercut cantilever piece and facing one side of the straight top block; the front end of the transverse ejector pin is provided with an arc-shaped groove adapted to the half arc-shaped protrusion on the cantilever end near the top end.

4. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 3, characterized in that: The lateral moving direction of the lateral ejector pin is perpendicular to the undercut cantilever piece.

5. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 1, characterized in that: The number of the transverse ejector pins is a pair and they are arranged parallel to each other and spaced apart.

6. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 5, characterized in that: A pair of slide grooves slidably matched with the guide heads on a pair of transverse ejector pins are correspondingly arranged on the front and rear sides of the vertical slide rail.

7. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 1, characterized in that: A pair of straight top push rods are connected to the straight top push block.

8. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 1, characterized in that: The straight ejector block is provided with a sliding sleeve, and the rear outer circle of the transverse ejector pin is movably provided on the sliding sleeve.

9. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 1, characterized in that: A core shrinking assembly for facilitating the removal of parts during demoulding is also provided on the straight top block, and the core shrinking assembly includes a core shrinking mounting block provided on the straight top block, a telescopic core head provided on one side of the core shrinking mounting block, and a connecting screw provided on the other side of the core shrinking mounting block, wherein the threaded section of the connecting screw passes through the through hole on the core shrinking mounting block and is threadedly connected with the telescopic core head, a compression spring is provided between the screw head of the connecting screw and the core shrinking mounting block, the outer circle of the telescopic core head is movably provided in the core shrinking mounting hole of the straight top block, and the front end face of the telescopic core head is flush with the cavity surface of the straight top block.

10. The improved ejection structure of the injection mold for the rear bumper of an automobile according to claim 9, characterized in that: After the telescopic core head is threadedly connected to the threaded section of the connecting screw, circumferential anti-rotation fixation is also achieved through pins.

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