A pen tip injection mold

Abstract

This utility model provides a pen tip injection mold, belonging to the field of injection mold technology. The pen tip injection mold includes a top plate, an upper template, a left sliding plate, a left mold core, a right sliding plate, a right mold core, a forming rod, a lower template, and a mounting plate. The top plate is fixed to the upper template, the lower template is fixed to the mounting plate, the left sliding plate is fixed to the left mold core, and the right sliding plate is fixed to the right mold core. Forming grooves are formed on the inner sides of both the left and right mold cores. The left and right sliding plates are slidably mounted on the upper surface of the lower template. When the upper template moves downwards, the trapezoidal groove contacts the ramp and pushes the left and right sliding plates closer together until the left and right mold cores are in contact. The forming rod is vertically fixed to the mounting plate, and a stripper sleeve that can slide up and down along the forming rod is fitted on the forming rod. The upper end of the forming rod passes through the forming groove, and a stripper rod that lifts the stripper sleeve passes through the mounting plate. Stripping is quick and safe; the stripper sleeve fits snugly with the forming rod, easily lifting the pen tip without damaging it.

Description

Technical Field

[0001] This utility model belongs to the field of injection mold technology, and relates to a pen tip injection mold. Background Technology

[0002] A ballpoint pen consists of a pen tip, a pen barrel, and a refill. The refill is inserted into the pen barrel, and the pen tip is threadedly connected to the pen barrel, with the front end of the refill protruding from the pen tip. Because the pen tip has a thin wall, it is difficult to unload, resulting in ejection problems. In some molds, after the pen tip is injection molded, it requires manual manipulation using tools to forcefully lift the pen tip from the mold core before the next injection molding. This not only causes significant wear on the mold but also results in slow unloading and potential product damage. Therefore, there is an urgent need for a mold that can automatically lift the pen tip from the mold core after injection molding. Utility Model Content

[0003] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a pen tip injection mold that can quickly lift thin-walled pen tips for convenient and safe unloading.

[0004] The objective of this utility model can be achieved through the following technical solution: A pen tip injection mold includes a top plate, an upper template, a left sliding plate, a left mold core, a right sliding plate, a right mold core, a forming rod, a lower template, and a mounting plate. The top plate is fixed to the upper template, and the lower template is fixed to the mounting plate. The lower template has a raised stop bar in the middle. The left sliding plate is fixed to the left mold core, and the right sliding plate is fixed to the right mold core. Forming grooves are formed on the inner sides of both the left and right mold cores. The left and right sliding plates are slidably disposed on the upper end face of the lower template. Spring grooves are opened on the inner side, and extension springs are installed in the spring grooves. The extension springs abut against the side of the stop bar. A trapezoidal groove is opened on the upper template. The left and right sliding plates have inclined ramps. When the upper template moves down, the trapezoidal groove can contact the ramps and push the left and right sliding plates to move closer to each other until the left and right mold cores are in contact. The forming rod is vertically fixed on the mounting plate. A stripper sleeve that can slide up and down along the forming rod is fitted on the forming rod. The upper end of the forming rod passes through the forming groove. A stripper rod that lifts the stripper sleeve passes through the mounting plate.

[0005] Furthermore, side plates are fixed to both sides of the lower end of the mounting plate, and a bottom plate is fixed to the lower end of the side plates. A lifting plate is provided between the two side plates. The lifting plate is fixed to the lower end of the unloading rod, and the upper end of the unloading rod is connected to the unloading sleeve. A clearance hole is opened on the bottom plate for the extension rod of the unloading cylinder to extend.

[0006] Furthermore, the forming rods are multiple and arranged in a straight line, with the lower ends of the forming rods fixed to the positioning plate, and the positioning plate has through holes for the unloading rods to pass through.

[0007] Furthermore, the lower template has protruding limiting blocks on both sides, and the bottom of the left and right sliding plates has grooves. When the left and right sliding plates slide outward, the limiting blocks can abut against the inner end of the grooves to prevent further sliding.

[0008] Furthermore, an ejector pin is fixed on the upper template, with the lower end of the ejector pin extending into the forming groove and abutting against the upper end of the forming rod.

[0009] Furthermore, a connection port is fixed on the top plate, and a hot runner pipe connected to the connection port is provided inside the top plate. Diversion pipes connected to the hot runner pipe are opened on the inner walls of the left and right mold cores, and these diversion pipes are connected to the molding groove. The connection port is connected to the feeding pipe. This mold can inject multiple pen heads at once, each pen head having its own diversion pipe, allowing the molten plastic to quickly and evenly fill the molding groove.

[0010] The top plate causes the lower mold plate to sink, and the trapezoidal groove prioritizes contact with the ramps of the left and right sliding plates. The extrusion ramps cause the left and right sliding plates to move towards the center, making the left and right mold cores fit together. Molten plastic is injected into the hot runner pipe through the injection molding machine via the feeding pipe, and then flows into each molding slot through the distribution pipe. After the pen tip cools and sets, the upper mold plate moves upward first, causing the ejector pin to move upward. After the extrusion pressure is lost, the extension spring pushes the left and right sliding plates outward. Then, the unloading cylinder is activated to lift the lifting plate, which drives the unloading rod to lift the unloading sleeve. The unloading sleeve pushes the pen tip upward, causing the pen tip to detach from the molding rod. The worker can easily remove the material. The pen tip connects with the cooled waste material in the distribution pipe. Removing the waste material yields the pen tip product.

[0011] Compared with existing technologies, this pen tip injection mold has the following advantages:

[0012] 1. Fast and safe unloading: The unloading sleeve fits snugly with the forming rod, easily lifting the pen tip without damaging it.

[0013] 2. Because the pen tip has external threads and cannot be ejected directly, this mold divides the core into two parts, left and right. It uses a sliding plate and extension spring to achieve automatic separation, and uses a downward trapezoidal groove to achieve automatic closure of the molding cavity. No additional power drive is required, saving energy. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view of the injection mold for this pen tip.

[0015] Figure 2 This is a structural diagram of the left mold core and the left sliding plate.

[0016] Figure 3 This is a schematic diagram of the heat flow pipes inside the top plate.

[0017] In the diagram, 1. Top plate; 2. Upper template; 21. Trapezoidal groove; 22. Ejector pin; 3. Left sliding plate; 31. Ramp; 32. Slide groove; 4. Left mold core; 41. Forming groove; 42. Diversion pipe; 5. Right sliding plate; 6. Right mold core; 7. Forming rod; 8. Lower template; 81. Stop bar; 82. Limiting block; 9. Mounting plate; 10. Extension spring; 11. Ejector sleeve; 12. Ejector rod; 13. Side plate; 14. Bottom plate; 141. Clearance hole; 15. Lifting plate; 16. Hot flow pipe; 17. Connection port; 18. Positioning plate; 19. Through hole. Detailed Implementation

[0018] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0019] like Figure 1 , Figure 2 As shown, this pen tip injection mold includes a top plate 1, an upper template 2, a left sliding plate 3, a left mold core 4, a right sliding plate 5, a right mold core 6, a forming rod 7, a lower template 8, and a mounting plate 9. The top plate 1 is fixed to the upper template 2, and the lower template 8 is fixed to the mounting plate 9. The lower template 8 has a raised stop bar 81 in the middle. The left sliding plate 3 is fixed to the left mold core 4, and the right sliding plate 5 is fixed to the right mold core 6. Forming grooves 41 are opened on the inner sides of both the left and right mold cores 4 and 6. The left and right sliding plates 3 and 5 are slidably disposed on the upper end face of the lower template 8. Spring grooves are opened on the inner sides of both the left and right sliding plates 3 and 5. An extension spring 10 is provided inside, which abuts against the side of the stop bar 81. A trapezoidal groove 21 is opened on the upper template 2. The left slide plate 3 and the right slide plate 5 have inclined ramps 31. When the upper template 2 moves down, the trapezoidal groove 21 can contact the ramp 31 and push the left slide plate 3 and the right slide plate 5 to move closer to each other until the left mold core 4 and the right mold core 6 are in contact. The forming rod 7 is vertically fixed on the mounting plate 9. A discharge sleeve 11 that can slide up and down along the forming rod 7 is sleeved on the forming rod 7. The upper end of the forming rod 7 is inserted into the forming groove 41. A discharge rod 12 that lifts the discharge sleeve 11 is inserted inside the mounting plate 9.

[0020] Side plates 13 are fixed on both sides of the lower end of the mounting plate 9, and a base plate 14 is fixed at the lower end of the side plates 13. A lifting plate 15 is provided between the two side plates 13. The lifting plate 15 is fixed to the lower end of the unloading rod 12. The upper end of the unloading rod 12 is connected to the unloading sleeve 11. A clearance hole 141 is opened on the base plate 14 for the extension rod of the unloading cylinder to extend.

[0021] like Figure 2 The forming rod 7 has multiple rods arranged in a straight line. The lower end of the forming rod 7 is fixed on the positioning plate 18. The positioning plate 18 has a through hole 19 for the unloading rod 12 to pass through.

[0022] The lower template 8 has protruding limiting blocks 82 on both sides, and the bottom of the left slide plate 3 and the right slide plate 5 has a sliding groove 32. When the left slide plate 3 and the right slide plate 5 slide outward, the limiting blocks 82 can abut against the inner end of the sliding groove 32 to prevent further sliding.

[0023] A ejector pin 22 is fixed on the upper template 2. The lower end of the ejector pin 22 extends into the forming groove 41 and abuts against the upper end of the forming rod 7. Since the upper end of the pen tip is small, the inner hole is formed by the ejector pin 22. It is pulled out in advance before unloading to avoid damaging the end of the pen tip.

[0024] like Figure 3 As shown, a connection port 17 is fixed on the top plate 1. A hot flow pipe 16 communicating with the connection port 17 is provided inside the top plate 1. A diversion pipe 42 communicating with the hot flow pipe 16 is opened on the inner wall of the left mold core 4 and the right mold core 6. The diversion pipe 42 is connected to the molding groove 41. The connection port 17 is connected to the feeding pipe. This mold can inject multiple pen heads at one time. Each pen head has its own diversion pipe 42, so that the molten plastic can quickly and evenly fill the molding groove 41.

[0025] Workflow: The top plate 1 drives the lower template 8 to sink, and the trapezoidal groove 21 contacts the ramps 31 of the left and right slide plates 3 and 5 first. The pressure ramps 31 cause the left and right slide plates 3 and 5 to move towards the middle, so that the left mold core 4 and the right mold core 6 fit together. The molten plastic is injected into the hot flow pipe 16 through the injection molding machine through the feeding pipe, and then flows into each molding groove 41 through the diversion pipe 42. After the pen tip cools and sets, the upper template 2 moves upward first, driving the ejector pin 22 to move upward. After the extrusion pressure is lost, the extension spring 10 pushes the left and right slide plates 3 and 5 outward. Then the unloading cylinder is activated to lift the lifting plate 15, which drives the unloading rod 12 to lift the unloading sleeve 11. The unloading sleeve 11 pushes the pen tip upward, so that the pen tip is separated from the molding rod 7. The worker can easily pick up the material. The pen tip is connected to the waste material cooled in the diversion pipe 42. The waste material is removed to obtain the pen tip product.

[0026] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A pen point injection mold, comprising a top plate (1), an upper mold plate (2), a left slide plate (3), a left mold core (4), a right slide plate (5), a right mold core (6), a forming rod (7), a lower mold plate (8), a mounting plate (9), characterized in that, The top plate (1) is fixed to the upper template (2), the lower template (8) is fixed to the mounting plate (9), the lower template (8) has a raised baffle (81) in the middle, the left sliding plate (3) is fixed to the left mold core (4), the right sliding plate (5) is fixed to the right mold core (6), the inner sides of the left mold core (4) and the right mold core (6) are both provided with forming grooves (41), the left sliding plate (3) and the right sliding plate (5) are respectively slidably set on the upper end face of the lower template (8), the inner sides of the left sliding plate (3) and the right sliding plate (5) are respectively provided with spring grooves, the spring grooves are provided with extension springs (10), the extension springs (10) abut against the side of the baffle (81), the upper template (2) A trapezoidal groove (21) is opened on the upper part. The left slide plate (3) and the right slide plate (5) have inclined ramps (31). When the upper template (2) moves down, the trapezoidal groove (21) can contact the ramp (31) and push the left slide plate (3) and the right slide plate (5) to come closer to each other until the left mold core (4) and the right mold core (6) fit together. The forming rod (7) is vertically fixed on the mounting plate (9). The forming rod (7) is fitted with a discharge sleeve (11) that can slide up and down along the forming rod (7). The upper end of the forming rod (7) is inserted into the forming groove (41). The mounting plate (9) is fitted with a discharge rod cylinder (12) that lifts the discharge sleeve (11).

2. The pen tip injection mold according to claim 1, characterized in that, The mounting plate (9) has side plates (13) fixed on both sides of its lower end, and a bottom plate (14) fixed on the lower end of the side plates (13). A lifting plate (15) is provided between the two side plates (13). The lifting plate (15) is fixed to the lower end of the unloading rod cylinder (12). The upper end of the unloading rod cylinder (12) is connected to the unloading sleeve (11). The bottom plate (14) has a clearance hole (141) for the extension rod of the unloading cylinder to extend.

3. The pen tip injection mold according to claim 1, characterized in that, The forming rod (7) has multiple rods arranged in a straight line. The lower end of the forming rod (7) is fixed on the positioning plate (18). The positioning plate (18) has a through hole (19) for the unloading rod cylinder (12) to pass through.

4. The pen tip injection mold according to claim 1, characterized in that, The lower template (8) has protruding limiting blocks (82) on both sides, and the bottom of the left slide plate (3) and the right slide plate (5) has a sliding groove (32). When the left slide plate (3) and the right slide plate (5) slide outward, the limiting block (82) can abut against the inner end of the sliding groove (32) to prevent further sliding.

5. A pen tip injection mold according to claim 1, characterized in that, A ejector pin (22) is fixed on the upper template (2). The lower end of the ejector pin (22) extends into the forming groove (41) and abuts against the upper end of the forming rod (7).

6. A pen tip injection mold according to claim 1, characterized in that, A connection port (17) is fixed on the top plate (1). A hot flow pipe (16) connected to the connection port (17) is provided inside the top plate (1). A diversion pipe (42) connected to the hot flow pipe (16) is opened on the inner wall of the left mold core (4) and the right mold core (6). The diversion pipe (42) is connected to the molding groove (41).

Images