Hot Runner of Vehicle Seat Back Injection Mold

Abstract

The present invention belongs to the field of hot runner frames for injection molds, and specifically discloses a hot runner frame for a vehicle seat back injection mold. An accommodating chamber is provided on the upper mold, and an insertion hole is provided at the bottom of the accommodating chamber. The hot runner frame is fixedly connected to the upper mold. An injection port is provided on the hot runner frame. The hot runner tube includes an outer tube and an inner tube. An annular groove is provided on the hot runner frame, and the annular groove is located on the outer periphery of the injection hole. The inner tube is slidably connected in the annular groove. A sliding hole communicating with the injection hole is opened on the hot runner frame, and a cutting plate is hermetically slidably connected in the sliding hole. A cutting hole having the same size as the injection hole is provided on the cutting plate. A slider is slidably connected to the upper mold, and the cutting plate is fixedly connected to the slider. A Y-shaped clamping block is slidably connected to the upper mold. A bayonet matching the clamping block is opened on the outer periphery of the outer tube. A pressing rod is hinged to the slider, one end of the pressing rod is fixedly connected to a hinged rod, and the end of the hinged rod away from the pressing rod is hinged to the inner tube. This device solves the problem in the prior art that the threaded connection between the hot runner tube and the injection hole increases the use cost.

Description

Technical Field

[0001] The present invention belongs to the field of hot runner systems for injection molds. Background Art

[0002] A hot runner system ensures that the plastic in the runner and gate remains in a molten state by heating. Since heating rods and heating coils are provided near or at the center of the runner, the entire runner from the outlet of the injection machine nozzle to the gate is in a high-temperature state, keeping the plastic in the runner molten. Generally, it is not necessary to open the runner to remove the plastic after shutdown. Therefore, the hot runner process is sometimes called a hot manifold system or a runnerless molding process. For plastic parts with high appearance requirements, when restarting the machine, it is only necessary to heat the hot runner system to the required temperature. When producing automotive backrests by injection molding, the hot runner process is used to improve the surface quality of the products and increase the injection molding efficiency. However, when the mold is opened after the automotive backrest is molded, the hot runner system needs to be separated from the automotive backrest. When the plastic in the hot runner nozzle of the hot runner system detaches from the automotive backrest, burrs are often left on the automotive backrest or the surface of the automotive backrest is torn, resulting in damage to the surface appearance of the automotive backrest.

[0003] In addition, in the prior art, since the hot runner tube is usually threadedly connected to the injection hole on the hot runner system, when removing the hot runner tube from the hot runner system, the hot runner tube needs to be rotated. The rotation causes the plastic in the hot runner tube to break, and the breakage of the plastic damages the internal thread on the injection hole. After the internal thread is damaged, the hot runner system has to be replaced, increasing the usage cost. Summary of the Invention

[0004] The purpose of the present invention is to provide a hot runner system for an automotive backrest injection mold to solve the problem of increased usage cost caused by the threaded connection between the hot runner tube and the injection hole in the prior art.

[0005] To achieve the above purpose, the basic solution of the present invention provides a hot runner system for an automotive backrest injection mold, including a ball screw, an upper mold, a hot runner tube, and a hot runner system. An accommodation chamber is provided on the upper mold, and an insertion hole is provided at the bottom of the accommodation chamber. The hot runner system is fixedly connected to the upper mold, and an injection port is provided on the hot runner system. The hot runner tube includes an outer tube and an inner tube. An annular groove is provided on the hot runner system, and the annular groove is located outside the injection hole. The inner tube is slidably connected to the annular groove. A sliding hole communicating with the injection hole is provided on the hot runner system, and a cutting plate is hermetically slidably connected in the sliding hole. A cutting hole having the same size as the injection hole is provided on the cutting plate. A slider is slidably connected to the upper mold, and the cutting plate is fixedly connected to the slider. A Y-shaped clamping block is slidably connected to the upper mold. A bayonet matching the clamping block is provided on the outer periphery of the outer tube. A pressure rod is hinged to the slider, one end of the pressure rod is fixedly connected to a hinged rod, and the end of the hinged rod away from the pressure rod is hinged to the inner tube.

[0006] The principle of this basic solution is as follows: Initially, the clamping block is snapped into the buckle, and the cutting hole is aligned with the injection hole. When the vehicle seat back needs to be demolded after molding, the lower end of the pressure rod is moved away from the inner tube, causing the pressure rod to rotate counterclockwise around the hinge point on the hinge seat. The end of the pressure rod close to the inner tube swings upward, driving the inner tube to move upward. The outer tube is fixed due to the clamping of the clamping block. When the inner tube moves upward, it separates from the insertion hole, and the plastic material originally inside the inner tube leaks out.

[0007] When the pressure rod swings, the reaction force exerted by the inner tube on the pressure rod causes the slider to slide away from the inner tube, and the slider drives the cutting plate to move, so that the cutting plate cuts off the plastic material in the injection hole.

[0008] The beneficial effects of this basic solution are as follows: 1. This device replaces the connection method between the inner tube and the hot runner with a sliding connection, avoiding scratches on the internal thread of the injection hole caused by plastic material during thread connection.

[0009] 2. This device moves the inner tube upward, allowing the plastic material at the lower part of the inner tube to leak out, facilitating subsequent cutting.

[0010] 3. When the inner tube moves upward in this device, it drives the cutting plate to cut off the plastic material in the injection hole, avoiding the need to manually twist off the plastic material when removing the hot runner tube, and facilitating the replacement of the hot runner tube.

[0011] Optimization Solution 1: It further includes a ball screw. The ball screw includes a ball nut, and the ball nut is rotatably connected to the lower part of the outer tube. The inner tube is provided with a thread matching the ball nut. A transmission gear is fixedly connected to the outer circumference of the ball nut. A first insertion rack and a second insertion rack that are parallel to each other are engaged with the transmission gear. A first cutter and a second cutter for cutting plastic material are respectively fixedly connected to the first insertion rack and the second insertion rack. The first cutter and the second cutter are slidably connected to the bottom of the accommodation chamber. When the inner tube rises, it drives the ball nut to rotate, causing the transmission gear to drive the transmission rack to rotate, and then the cutters on both sides cut off the leaked plastic material, avoiding the situation where the hot runner forcibly drives the plastic material in the inner tube to move upward during mold opening, which may damage the surface appearance of the vehicle seat back.

[0012] Optimization Solution 2: A return spring is provided on the slider, and the end of the return spring away from the slider is fixedly connected to the upper mold. The setting of the return spring enables the slider to return to its original position when not under force, so that the pressure rod swings back, causing the inner tube to receive a downward force. Furthermore, during the injection molding of the vehicle seat back, it prevents the inner tube from moving upward due to the injection pressure.

[0013] Optimization Solution 3: The pressure rod is fixedly connected to the hinge rod by threads. Thread connection is convenient for disassembly and facilitates the replacement of the inner tube.

[0014] Optimization Solution 4: The cutting plate is fixedly connected to the slider by threads. Thread connection is convenient for disassembly and facilitates the replacement of the inner tube. Description of the Drawings

[0015] Figure 1 Structural schematic diagram of the hot runner of the vehicle seat back injection mold according to an embodiment of the present invention;

[0016] Figure 2 is Figure 1 The enlarged view of part A in Specific embodiments

[0017] The present invention will be further described in detail below through specific embodiments:

[0018] The reference numerals in the accompanying drawings of the specification include: pressure rod 1, hot runner 2, upper mold 3, return spring 4, hinge seat 5, cutting plate 6, injection hole 7, inner tube 8, slider 9, outer tube 10, clamping block 11, ball nut 12, transmission gear 13, first rack 14, first cutter 15, second cutter 16.

[0019] Embodiment: The hot runner 2 of the vehicle seat back injection mold in this solution, Figure 1 and Figure 2 As shown, it includes a ball screw, an upper mold 3, a hot runner tube and a hot runner 2. The upper mold 3 is provided with a receiving chamber, and an insertion hole is provided at the bottom of the receiving chamber. The hot runner 2 is fixedly connected to the upper mold 3 by a stud bolt. The hot runner 2 is provided with a vertically downward injection port. The hot runner tube includes an outer tube 10 and an inner tube 8. The hot runner 2 is provided with an annular groove, and the annular groove is located on the outer periphery of the injection hole 7. The top of the inner tube 8 is slidably connected in the annular groove. A sliding hole communicating with the injection hole 7 is opened on the hot runner 2. The sliding hole is horizontally arranged, and a cutting plate 6 is hermetically slidably connected in the sliding hole. A sealing strip is installed between the cutting plate 6 and the sliding hole. The cutting plate 6 is provided with a cutting hole having the same size as the injection hole 7. The thickness of the cutting plate 6 is 2 mm, and the wall of the cutting hole is in the shape of a blade.

[0020] A sliding groove is opened on the upper mold 3, and a slider 9 is slidably connected in the sliding groove. The cutting plate is fixedly connected to the slider 9 through a connecting rod fixed thereto by a thread. A return spring 4 is provided on the slider 9, and the end of the return spring 4 away from the slider 9 is fixedly connected to the upper mold 3. The ball screw includes a ball nut 12. The ball nut 12 is rotatably connected to the lower part of the outer tube 10. The inner tube 8 is provided with a thread matching the ball nut 12. A transmission gear 13 is fixedly connected to the outer periphery of the ball nut 12. The transmission gear 13 is engaged with a first insertion rack and a second insertion rack that are parallel to each other. A first cutter 15 and a second cutter 16 for cutting the condensate are respectively fixedly connected to the first insertion rack and the second insertion rack. The first cutter 15 and the second cutter 16 are slidably connected to the bottom of the receiving chamber. The blades of the first cutter 15 and the second cutter 16 are both in contact with the bottom of the receiving chamber. The cross-sections of the blades of the first cutter 15 and the second cutter 16 are both in the shape of a right triangle, so that the fracture of the condensate is flat.

[0021] A Y-shaped clamping block 11 is slidably connected to the upper mold 3, and a bayonet matching the clamping block 11 is opened on the outer periphery of the outer tube 10. A hinge seat 5 is provided on the slider 9, and a pressure rod 1 is hinged on the hinge seat 5. One end of the pressure rod 1 is fixedly connected with a hinge rod by threads, and the end of the hinge rod far from the pressure rod 1 is hinged on the inner tube 8. A vertical through groove is provided on the outer tube 10, and the hinge point of the telescopic rod and the inner tube 8 is located in the through groove.

[0022] Initially, the clamping block 11 is snapped into the buckle, and the cutting hole is aligned with the injection hole 7. When the vehicle seat back needs to be demolded after molding, press the end of the pressure rod 1 far from the inner tube 8 downward, so that the pressure rod 1 rotates counterclockwise around the hinge point on the hinge seat 5, and the end of the pressure rod 1 close to the inner tube 8 swings upward, driving the inner tube 8 to move upward. The outer tube 10 is kept stationary due to the clamping of the clamping block 11. When the inner tube 8 moves upward, it is separated from the insertion hole, and the plastic material originally in the inner tube 8 leaks out.

[0023] When the inner tube 8 moves upward, the thread on the inner tube 8 drives the ball nut 12 to rotate. When the ball nut 12 rotates, it drives the transmission gear 13 to rotate. The transmission gear 13 drives the first insertion rack and the second insertion rack to move towards each other, thereby driving the first cutting knife 15 and the second cutting knife 16 to move towards each other and cut the plastic material.

[0024] At the same time, when the pressure rod 1 swings, the reaction force of the inner tube 8 on the pressure rod 1 makes the slider 9 move to the left, and the slider 9 drives the cutting plate to move to the left, so that the cutting plate cuts the plastic material in the injection hole 7.

[0025] The above are only embodiments of the present invention, and well-known common knowledge in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to explain the content of the claims.

Claims

1. The hot runner of the vehicle seat back injection mold is characterized in that: It includes a ball screw, an upper mold, a hot runner tube and a hot runner holder. An accommodation chamber is provided on the upper mold, and an insertion hole is provided at the bottom of the accommodation chamber. The hot runner holder is fixedly connected to the upper mold, and an injection port is provided on the hot runner holder. The hot runner tube includes an outer tube and an inner tube. An annular groove is provided on the hot runner holder, and the annular groove is located on the outer periphery of the injection hole. The inner tube is slidably connected in the annular groove. A sliding hole communicating with the injection hole is provided on the hot runner holder, and a cutting plate is hermetically slidably connected in the sliding hole. A cutting hole having the same size as the injection hole is provided on the cutting plate. A slider is slidably connected to the upper mold, and the cutting plate is fixedly connected to the slider. A Y-shaped clamping block is slidably connected to the upper mold. A bayonet matching the clamping block is provided on the outer periphery of the outer tube. A pressing rod is hinged to the slider, one end of the pressing rod is fixedly connected to a hinged rod, and the end of the hinged rod away from the pressing rod is hinged to the inner tube; the pressing rod is fixedly connected to the hinged rod by threads.

2. The hot runner of the vehicle seat back injection mold according to claim 1, characterized in that: It further includes a ball screw which includes a ball nut. The ball nut is rotatably connected to the lower part of the outer tube. Threads matching the ball nut are provided on the inner tube. A transmission gear is fixedly connected to the outer periphery of the ball nut. A first insertion rack and a second insertion rack which are parallel to each other are engaged with the transmission gear. A first cutter for cutting the condensate and a second cutter for cutting the condensate are respectively fixedly connected to the first insertion rack and the second insertion rack. The first cutter and the second cutter are slidably connected to the bottom of the accommodation chamber.

3. The hot runner of the vehicle backrest injection mold according to claim 2, characterized in that: The cutting plate is fixedly connected to the slider by threads.

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