Injection mold for special-shaped thin-wall part of helmet

Abstract

The utility model relates to the technical field of injection molds, and discloses an injection mold for a special-shaped thin-wall part of a helmet, which comprises a fixed mold and a movable mold matched with the fixed mold, a forming concave surface is arranged on one side, facing the fixed mold, of the movable mold; a forming convex surface is arranged on one side, facing the movable mold, of the fixed mold; and the forming concave surface and the forming convex surface are matched for forming the jaw guard. The sliding groove is formed in the side, facing the movable mold, of the fixed mold body, the two sliding blocks used for forming the fork handle of the protective jaw are arranged on the sliding groove, and meanwhile the inclined guide rod is connected to the side, facing the fixed mold, of the movable mold to be matched with the sliding blocks, so that when the helmet protective jaw is formed and needs to be opened, the mold can be opened; the sliding blocks can be driven by the inclined guide rods to slide in the sliding grooves, the two sliding blocks slide in the opposite directions, and after the two sliding blocks slide in the opposite directions, the fork handle of the jaw protector is not extruded by the fork handle forming convex surface and the fork handle forming concave surface any more, so that the whole jaw protector including the fork handle is easily separated from the fixed die.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molds, in particular to an injection mold for a special-shaped thin-walled part of a helmet. Background Art

[0002] The jaw guard is a special-shaped thin-walled part in a full-face helmet, that is, there is a part below the nose to protect the lips and lower jaw, which can provide better protection for the face when being impacted. The Chinese patent document with the publication number CN105901820B discloses a variable jaw guard structure helmet based on gear constraint, and specifically discloses that the jaw guard has two fork handles separately arranged on both sides of the helmet shell body. However, in actual injection molding production, it is found that for the injection molding of the jaw guard, there is a problem of difficult demolding. Especially at the contact between the jaw guard fork handle and the mold, it is difficult to separate the jaw guard fork handle from the mold, resulting in the problem of difficult demolding of the jaw guard.

[0003] Obviously, the prior art still needs to be improved. Summary of the Utility Model

[0004] The purpose of the utility model is to provide an injection mold for a special-shaped thin-walled part of a helmet, aiming at solving the problem of difficult demolding of the jaw guard.

[0005] To achieve the above purpose, the solution provided by the utility model is:

[0006] An injection mold for a special-shaped thin-walled part of a helmet, comprising a fixed mold and a movable mold that fits with the fixed mold; on the side of the movable mold facing the fixed mold, there is a molding concave surface, and on the side of the fixed mold facing the movable mold, there is a molding convex surface; the molding concave surface and the molding convex surface cooperate to mold the jaw guard; the fixed mold includes a fixed mold body and two sliders; on the side of the fixed mold body facing the movable mold, there is a chute; the two sliders are mirror images of each other and are slidably arranged in the chute; the slider is provided with a fork handle molding convex surface, and the fork handle molding convex surface and the molding concave surface are used to mold the jaw guard fork handle; on the side of the movable mold facing the fixed mold, two inclined guide rods are connected; the two inclined guide rods are mirror images of each other, and the inclined guide rods are respectively movably connected with the two sliders; the slider is provided with an inclined hole channel that cooperates with the inclined guide rod, and the inclined hole channel inclines towards the center of the mold.

[0007] Preferably, the slider includes a sliding part and a molding convex part; the fork handle molding convex surface is formed on the molding convex part; two embedding grooves are formed on the fixed mold body; the two embedding grooves are respectively located on both sides in the length direction of the chute, and the embedding grooves communicate with the chute; the molding convex part cooperates with the embedding groove.

[0008] Preferably, first springs are connected to the two side walls of the chute in the length direction thereof; a first cavity for accommodating the first springs is provided on the sliding part; the first springs are arranged along the length direction of the chute, and the two ends of the first springs are fixedly connected to the chute wall and the cavity wall of the first cavity respectively.

[0009] Preferably, the sliding part is in an inverted T shape, and a limiting clamping groove is inwardly provided on the chute wall in the length direction; the bottom of the sliding part is clamped in the limiting clamping groove.

[0010] Preferably, a mounting block is provided on one side of the moving mold facing the fixed mold; the inclined guide rod is a T-shaped guide rod; a T-shaped hole matching with the upper end of the T-shaped guide rod is provided in the mounting block.

[0011] Preferably, the moving mold includes a moving mold body, a moving mold mounting base, a movable plate, an inserting rod, a second spring, a guiding seat and a forming insert;

[0012] The forming concave surface is provided on one side of the moving mold body facing the fixed mold; the moving mold body is arranged in the moving mold mounting base;

[0013] The movable plate is arranged on the side surface of the moving mold mounting base facing away from the fixed mold; the inserting rod is inserted into the moving mold mounting base; a second cavity is formed inside the moving mold mounting base; the second cavity is used for accommodating the inserting rod; the second spring is arranged in the second cavity and sleeved on the inserting rod, and the two ends of the second spring are fixedly connected to the cavity wall of the second cavity and the inner side of the movable plate at the same time;

[0014] The forming insert cooperates with the moving mold body to form the lip tip of the jaw guard; the guiding seat is fixedly connected to the movable plate, and the guiding seat is provided with an inclined guiding part; the guiding part inclines towards the fixed mold and is used for guiding the forming insert; a supporting concave surface for supporting the guiding seat and the forming insert is provided on the side of the moving mold body facing away from the fixed mold.

[0015] Preferably, the guiding part is a guiding strip in an inverted T shape; a slot is provided on one side of the forming insert facing the guiding part for clamping connection with the guiding part.

[0016] Preferably, the second cavity includes a front cavity, a middle cavity and a rear cavity which are mutually communicated; the front cavity is close to the movable plate; the middle cavity is located between the front cavity and the rear cavity, and the inner diameter of the middle cavity is smaller than the inner diameters of the front cavity and the rear cavity; the inner end of the inserting rod is threadedly installed in the rear cavity, and the rear cavity is communicated with the outside of the moving mold mounting base; the second spring is sleeved on the inserting rod, and the second spring is located in the front cavity.

[0017] Beneficial effects:

[0018] The utility model provides an injection mold for a special-shaped thin-walled part of a helmet. By arranging a chute on one side of the fixed mold body facing the movable mold, and arranging two sliders on the chute for forming the fork handles of the jaw guard, and at the same time connecting an inclined guide rod on the side of the movable mold facing the fixed mold to cooperate with the sliders, when the jaw guard of the helmet is formed and needs to be demolded, the sliders can be driven to slide in the chute by the inclined guide rod, and the two sliders slide towards each other. After the two sliders slide towards each other, the fork handles of the jaw guard are no longer extruded by the convex surface and concave surface for forming the fork handles, so the whole jaw guard including the fork handles is easily separated from the fixed mold. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the helmet jaw guard.

[0020] Figure 2 It is the overall structure diagram of the injection mold for the special-shaped thin-walled part of the helmet provided by the utility model.

[0021] Figure 3 It is the structural schematic of the fixed mold Figure 1 .

[0022] Figure 4 It is the structural schematic of the fixed mold Figure 2 .

[0023] Figure 5 It is Figure 4 The enlarged view of part A in

[0024] Figure 6 It is the cross-section of the injection mold for the special-shaped thin-walled part of the helmet provided by the utility model Figure 1 .

[0025] Figure 7 It is Figure 6 The enlarged view of part B in

[0026] Figure 8 It is the cross-section of the injection mold for the special-shaped thin-walled part of the helmet provided by the utility model Figure 2 .

[0027] Figure 9 It is the cross-section of the injection mold for the special-shaped thin-walled part of the helmet provided by the utility model Figure 3 .

[0028] Figure 10 It is the schematic diagram of the sliding fit between the guide seat and the forming insert.

[0029] Explanation of the reference numerals in the drawings:

[0030] 1 - Fixed mold; 11 - Fixed mold body; 111 - Forming convex surface; 112 - Slide groove; 1121 - Limit card slot; 113 - Embedded groove; 12 - Slide block; 121 - Sliding part; 1211 - Tilted hole; 122 - Forming convex part; 1221 - Fork handle forming convex surface; 123 - First cavity;

[0031] 2 - Moving mold; 21 - Moving mold body; 211 - Forming concave surface; 212 - Support concave surface; 22 - Moving mold mounting seat; 221 - Second cavity; 2211 - Front cavity; 2212 - Hollow cavity; 2213 - Rear cavity; 23 - Movable plate; 231 - Positioning hole; 24 - Insert rod; 241 - Anti - detachment part; 25 - Second spring; 26 - Guide seat; 261 - Guide part; 27 - Forming insert; 271 - Slot;

[0032] 3 - Jaw guard; 31 - Fork handle; 32 - Lip tip;

[0033] 4 - Inclined guide rod; 5 - First spring;

[0034] 6 - Mounting block; 61 - T - shaped hole. Specific embodiments

[0035] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0036] It should be noted that all the directional indications (such as up, down, left, right, front, rear...) in the embodiments of the present utility model are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If this specific posture changes, the directional indications will also change accordingly.

[0037] It also should be noted that when an element is referred to as "fixed to" or "provided on" another element, it can be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0038] In addition, the descriptions involving "first", "second", etc. in the present utility model are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0039] Please refer to Figures 1 to 7 , the present utility model provides an injection mold for a special-shaped thin-walled part of a helmet. This injection mold is used on an injection molding machine for injection molding the jaw guard 3. Specifically, this injection mold for the special-shaped thin-walled part of the helmet includes a fixed mold 1 and a movable mold 2 that mates with the fixed mold 1.

[0040] Among them, on the side of the movable mold 2 facing the fixed mold 1, there is a forming concave surface 211, and on the side of the fixed mold 1 facing the movable mold 2, there is a forming convex surface 111; when the movable mold 2 and the fixed mold 1 are combined, the forming concave surface 211 and the forming convex surface 111 cooperate to form the jaw guard 3. It can be understood that the shapes of the forming concave surface 211 and the forming convex surface 111 can be set based on the shape of the jaw guard 3 to be formed.

[0041] Among them, the fixed mold 1 includes a fixed mold body 11 and two sliders 12; on the side of the fixed mold body 11 facing the movable mold 2, there is a chute 112; the two sliders 12 are arranged mirror-symmetrically and slidably disposed in the chute 112; the slider 12 is provided with a fork handle 31 forming convex surface 1221. When the movable mold 2 and the fixed mold 1 are combined, the position of the slider 12 is such that the fork handle 31 forming convex surface 1221 and the forming concave surface 211 can be used to form the fork handle 31 of the jaw guard 3.

[0042] Further, two inclined guide rods 4 are connected to the side of the moving mold 2 facing the fixed mold 1; the two inclined guide rods 4 are arranged as mirror images of each other, and the inclined guide rods 4 are respectively movably connected to the two sliders 12; the sliders 12 are provided with inclined channels 1211 that cooperate with the inclined guide rods 4, that is, the inclined guide rods 4 can extend into the inclined channels 1211; the inclined channels 1211 are inclined towards the center of the mold. When the jaw guard 3 needs to be demolded after being molded, the moving mold 2 and the fixed mold 1 are separated. During the process of the moving mold 2 moving away from the fixed mold 1, the inclined guide rods 4 will also move together with the moving mold 2. Therefore, in order to maintain the mating relationship with the inclined channels 1211, the inclined guide rods 4 will drive the sliders 12 to slide in the sliding grooves 112, and cause the two sliders 12 to slide towards each other. After the two sliders 12 slide towards each other, the fork handle 31 of the jaw guard 3 is no longer squeezed by the convex surface 1221 of the fork handle 31 and the concave surface 211 of the mold. Therefore, the entire jaw guard 3 including the fork handle 31 is easily separated from the fixed mold 1.

[0043] As Figures 4 to 7 shown, in a preferred embodiment of the present invention, the slider 12 includes a sliding portion 121 and a forming convex portion 122; the convex surface 1221 of the fork handle 31 is formed on the forming convex portion 122; two embedding grooves 113 are formed on the fixed mold body 11; the two embedding grooves 113 are respectively located on both sides of the sliding groove 112 in the length direction, and the embedding grooves 113 communicate with the sliding groove 112; the forming convex portion 122 cooperates with the embedding groove 113. During the process of the moving mold 2 and the fixed mold 1 being closed, the inclined guide rods 4 in the inclined channels 1211 will drive the sliders 12 to slide towards the directions where their respective corresponding embedding grooves 113 are located. Until the moving mold 2 and the fixed mold 1 are combined together, the forming convex portion 122 is exactly located in the embedding groove 113. At this time, the sliding portion 121 cannot continue to slide due to the blockage of the groove wall of the sliding groove 112. Thus, it can be ensured that during the injection molding operation, plastic products that meet the design requirements can be injection molded.

[0044] As Figure 6 and Figure 7 shown, in a preferred embodiment of the present invention, the two side groove walls in the length direction of the sliding groove 112 are connected with a first spring 5; the sliding portion 121 is provided with a first cavity 123 for accommodating the first spring 5; the first spring 5 is arranged along the length direction of the sliding groove 112, and both ends of the first spring 5 are fixedly connected to the groove wall of the sliding groove 112 and the cavity wall of the first cavity 123 respectively.

[0045] The first spring 5 is in a compressed state when the forming convex portion 122 is located in the embedding groove 113. When demolding, the moving mold 2 cannot restrict the movement of the slider 12. At this time, the first spring 5 will generate a force on the sliding portion 121 in order to reset. The generation of this force enables the two sliders 12 to slide towards each other, thus ensuring that the entire jaw guard 3 including the fork handle 31 of the jaw guard 3 can be smoothly demolded.

[0046] As Figures 4 to 6 shown, in a preferred embodiment of the present utility model, the sliding portion 121 is in an inverted T shape, and the groove wall of the sliding groove 112 in the length direction is provided with a limiting card slot 1121 inwardly; the bottom of the sliding portion 121 is clamped in the limiting card slot 1121, thereby ensuring that the slider 12 cannot fall off the sliding groove 112.

[0047] As Figure 6 and Figure 7 shown, in a preferred embodiment of the present utility model, an installation block 6 is provided on one side of the moving mold 2 facing the fixed mold 1. The installation block 6 is used to install the inclined guide rod 4, and when the moving mold 2 and the fixed mold 1 are combined together, the installation block 6 can also press the sliding portion 121, so that when the injection molding operation is carried out, the movement of the slider 12 is restricted.

[0048] As Figure 6 and Figure 7 shown, in a preferred embodiment of the present utility model, the inclined guide rod 4 is a T-shaped guide rod; a T-shaped hole 61 matching the upper end of the T-shaped guide rod is provided in the installation block 6. The T-shaped hole 61 can ensure that the rod body of the inclined guide rod 4 passes through the installation block 6 downward, and at the same time, the upper end of the T-shaped guide rod is always located in the T-shaped hole 61.

[0049] As Figures 8 to 10 shown, in a preferred embodiment of the present utility model, the moving mold 2 includes a moving mold body 21, a moving mold mounting seat 22, a movable plate 23, a plug rod 24, a second spring 25, a guide seat 26, and a forming insert 27.

[0050] Among them, the moving mold body 21 cooperates with the fixed mold body 11 for injection molding the jaw guard 3, so the forming concave surface 211 is designed on the side of the moving mold body 21 facing the fixed mold body 11 (fixed mold 1). The moving mold mounting seat 22 is used to mount the moving mold body 21, and the moving mold body 21 is mounted in the moving mold mounting seat 22. It can be understood that the fixed mold 1 should also include a fixed mold 1 mounting seat that cooperates with the moving mold mounting seat 22.

[0051] Among them, the movable plate 23 is arranged on the side surface of the movable mold mounting seat 22 facing away from the fixed mold 1. The insertion rod 24 is inserted into the movable mold mounting seat 22. A second cavity 221 is provided inside the movable mold mounting seat 22. It can be understood that the second cavity 221 is used to accommodate the insertion rod 24. The second spring 25 is provided in the second cavity 221, and the second spring 25 is sleeved on the insertion rod 24. The two ends of the second spring 25 are respectively fixedly connected to the cavity wall of the second cavity 221 and the inner side of the movable plate 23. When the movable mold 2 and the fixed mold 1 are put together, the movable plate 23 is in a compressed state, and the second spring 25 is in a compressed state; when the mold is opened, the movable plate 23 is no longer under pressure. At this time, the second spring 25 will move the movable plate 23 away from the movable mold mounting seat 22 in order to reset.

[0052] The molding insert 27 cooperates with the movable mold body 21 to form the lip tip 32 of the jaw guard 3. The guide seat 26 is fixedly connected to the movable plate 23 and is provided with an inclined guide portion 261. The guide portion 261 is tilted toward the fixed mold 1 and serves to guide the molding insert 27. A supporting concave surface 212 for supporting the guide seat 26 and molding insert 27 is provided on the side of the movable mold body 21 facing away from the fixed mold 1. The supporting concave surface 212 forms a clearance fit with both the guide seat 26 and the molding insert 27.

[0053] As mentioned above, when the mold is opened, the second spring 25 will move the movable plate 23 away from the movable mold mounting seat 22 in order to reset, so the guide seat 26 fixedly connected to the movable plate 23 will also move with the movable plate 23, thereby separating the guide seat 26 from the molding insert 27; and when the guide seat 26 is separated from the molding insert 27, in order to maintain the connection relationship with the guide seat 26, the molding insert 27 will slide slightly along the guide part 261 toward the direction of the fixed mold 1, so that the molding insert 27 is separated from the inner side of the lip tip 32 of the jaw guard 3, ensuring that the jaw guard 3 can be smoothly demolded.

[0054] like Figure 10 As shown, in a preferred embodiment of the present invention, the guide portion 261 is an inverted T-shaped guide bar; the side of the molding insert 27 facing the guide portion 261 is provided with a groove 271 that is engaged with the guide portion 261, thereby ensuring that the guide seat 26 always maintains a connection relationship with the molding insert 27, thereby providing a guarantee for the smooth demoulding of the jaw guard 3, and when the mold is closed, it can also ensure that the molding insert 27 returns to the correct position, and can injection mold a plastic product that meets the design requirements.

[0055] like Figure 9As shown, in a preferred embodiment of the present utility model, a positioning hole 231 matching with the insertion rod 24 is provided on the movable plate 23. Thus, the movable plate 23 can be guided by means of the insertion rod 24, ensuring that the movable plate 23 will not tilt during the movement. After the moving die 2 and the fixed die 1 are clamped, the molding insert 27 can return to the correct position.

[0056] As Figure 9 shown, in a preferred embodiment of the present utility model, the second cavity 221 includes a front cavity 2211, a middle cavity 2212 and a rear cavity 2213 that communicate with each other. The front cavity 2211 is close to the movable plate 23. The middle cavity 2212 is located between the front cavity 2211 and the rear cavity 2213, and the inner diameter of the middle cavity 2212 is smaller than the inner diameters of the front cavity 2211 and the rear cavity 2213. The inner end of the insertion rod 24 is threadedly installed in the rear cavity 2213, and the rear cavity 2213 communicates with the outside of the moving die mounting seat 22 to facilitate inserting the insertion rod 24 into the second cavity 221 and installing the insertion rod 24. The second spring 25 is sleeved on the insertion rod 24, and the second spring 25 is located in the front cavity 2211. The two ends of the second spring 25 are respectively connected to the movable plate 23 and the cavity wall of the front cavity 2211.

[0057] By dividing the second cavity 221 into three sub-cavities and installing the second spring 25 in the front cavity 2211, the service length of the second spring 25 can be shortened without affecting the normal movement of the movable plate 23.

[0058] The above are only the preferred embodiments of the present utility model, and do not limit the patent scope of the present utility model accordingly. Any equivalent structural transformation made under the inventive concept of the present utility model by using the content of the specification and drawings of the present utility model, or any direct / indirect application in other related technical fields shall be included in the patent protection scope of the present utility model.

Claims

1. An injection mold for a special-shaped thin-walled part of a helmet, comprising a fixed mold and a movable mold that fits with the fixed mold; a molding concave surface is provided on one side of the movable mold facing the fixed mold, and a molding convex surface is provided on one side of the fixed mold facing the movable mold; the molding concave surface and the molding convex surface cooperate to form a jaw guard; it is characterized in that, The fixed mold includes a fixed mold body and two sliders; a slide groove is provided on the side of the fixed mold body facing the movable mold; the two sliders are mirror images of each other and slide in the slide groove; the slider is provided with a fork handle forming convex surface, and the fork handle forming convex surface and the forming concave surface are used to form the jaw guard fork handle; two inclined guide rods are connected to the side of the movable mold facing the fixed mold; the two inclined guide rods are mirror images of each other, and the inclined guide rods are movably connected to the two sliders respectively; the slider is provided with an inclined channel cooperating with the inclined guide rod, and the inclined channel is inclined toward the center of the mold.

2. The injection mold for the special-shaped thin-walled part of the helmet according to claim 1, characterized in that, The slider includes a sliding portion and a forming convex portion; the fork handle forming convex surface is formed on the forming convex portion; two embedding grooves are provided on the fixed mold body; the two embedding grooves are respectively located on both sides of the slide groove in the length direction, and the embedding grooves are connected to the slide groove; the forming convex portion cooperates with the embedding grooves.

3. The injection mold for the special-shaped thin-walled part of the helmet according to claim 2, characterized in that, The groove walls on both sides in the length direction of the slide are connected with a first spring; the sliding part is provided with a first cavity for accommodating the first spring; the first spring is arranged along the length direction of the slide, and the two ends of the first spring are fixedly connected to the groove wall of the slide and the cavity wall of the first cavity respectively.

4. The injection mold for the special-shaped thin-walled part of the helmet according to claim 2, characterized in that, The sliding portion is in an inverted T-shape, and a limiting slot is provided inwardly on the slot wall in the length direction of the slide; the bottom of the sliding portion is clamped in the limiting slot.

5. The injection mold for the special-shaped thin-walled part of the helmet according to claim 1, characterized in that, A mounting block is provided on one side of the movable die facing the fixed die; the mounting block is used for mounting the oblique guide rod.

6. The injection mold for the special-shaped thin-walled part of the helmet according to claim 5, characterized in that, The oblique guide rod is a T-shaped guide rod; a T-shaped hole matching the upper end of the T-shaped guide rod is provided in the mounting block.

7. The injection mold for the special-shaped thin-walled part of the helmet according to claim 1, wherein, The movable mold includes a movable mold body, a movable mold mounting seat, a movable plate, an insert rod, a second spring, a guide seat and a molding insert; The molding concave surface is provided on the side of the movable mold body facing the fixed mold; the movable mold body is provided in the movable mold mounting seat; The movable plate is arranged on a side of the movable mold mounting seat facing away from the fixed mold; the insertion rod is inserted into the movable mold mounting seat; a second cavity is defined inside the movable mold mounting seat; the second cavity is used to accommodate the insertion rod; the second spring is arranged in the second cavity, and the second spring is sleeved on the insertion rod, and the two ends of the second spring are fixedly connected to the cavity wall of the second cavity and the inner side of the movable plate respectively; The molding insert cooperates with the movable mold body to form the lip tip of the jaw guard; the guide seat is fixedly connected to the movable plate, and the guide seat is provided with an inclined guide portion; the guide portion is inclined toward the fixed mold and is used to guide the molding insert; the side of the movable mold body facing away from the fixed mold is provided with a supporting concave surface for supporting the guide seat and the molding insert.

8. The injection mold for the special-shaped thin-walled part of the helmet according to claim 7, characterized in that, The movable plate is provided with a positioning hole matched with the insertion rod.

9. The injection mold for the special-shaped thin-walled part of the helmet according to claim 7, wherein, The guide portion is an inverted T-shaped guide bar; a groove is provided on a side of the molding insert facing the guide portion to engage with the guide portion.

10. The injection mold for the special-shaped thin-walled part of the helmet according to claim 7, wherein, The second cavity includes a front cavity, a middle cavity, and a rear cavity that are interconnected; the front cavity is close to the movable plate; the hollow cavity is located between the front cavity and the rear cavity, and the inner diameter of the hollow cavity is smaller than the inner diameters of the front cavity and the rear cavity; The inner end of the insertion rod is threadedly installed in the rear cavity, and the rear cavity is communicated with the outside of the movable mold mounting seat; the second spring is sleeved on the insertion rod, and the second spring is located in the front cavity.

Images