A tie rod mechanism for an injection unit of an injection molding machine

Abstract

This invention proposes a pull rod mechanism for an injection unit of an injection molding machine, belonging to the technical field of injection molding machine equipment. The injection unit includes a base, a head plate mounted on the base, and a linear guide rail. A slidable pull rod mechanism is provided on the linear guide rail, and the pull rod mechanism is connected to the head plate. An electric injection mechanism is provided on the pull rod mechanism, which includes an injection table support. A motor is fixedly mounted at one end of the injection table support. The output shaft of the motor is connected to one end of a lead screw. A pull rod bushing is fitted on the lead screw, and the pull rod bushing moves back and forth along the length of the lead screw. One end of the pull rod bushing is fixedly connected to a lead screw nut on the lead screw, and the other end of the pull rod bushing is connected to one end of a pull rod shaft. The other end of the pull rod shaft is provided with a touch control component for limiting the movement of the injection unit. The pull rod mechanism of the injection unit of this invention has a compact design, small overall size, high precision, fast response speed, high transmission efficiency, is applicable to various injection molding machine models, and is easy to assemble, which helps to reduce assembly costs.

Description

Technical Field

[0001] This invention relates to the field of injection molding machine equipment technology, and in particular to a tie rod mechanism for an injection seat of an injection molding machine. Background Technology

[0002] Existing electric injection molding machines typically employ a dual-axis guided, dual-bearing load mechanism for the injection unit's tie rod. This mechanism involves two guide rods supporting the injection unit push plate, with a power-applying screw driving the push plate, which in turn drives two load-bearing shafts to move the injection unit forward and backward. This structure suffers from poor guiding accuracy, high guiding resistance, resulting in uneven injection resistance, slow response speed, and low transmission efficiency, thus affecting injection molding quality. Furthermore, this type of electric injection molding machine's tie rod mechanism is complex, time-consuming, labor-intensive, and costly to manufacture, making it difficult to assemble in production. Summary of the Invention

[0003] To address the above technical problems, this invention proposes a tie rod mechanism for the injection seat of an injection molding machine. This mechanism features a simple design, fast response, high efficiency, applicability to various injection molding machine models, improved ease of assembly, reduced assembly labor and time costs, and lower production costs.

[0004] This invention is achieved through the following technical solution:

[0005] A pull rod mechanism for an injection unit of an injection molding machine belongs to the technical field of injection molding machine equipment. The injection unit includes a base, a head plate and a linear guide rail on the base. A slidable pull rod mechanism is provided on the linear guide rail. The pull rod mechanism is connected to the head plate. The pull rod mechanism includes an injection stage support. A motor is fixedly installed at one end of the injection stage support. The output shaft of the motor is connected to one end of a lead screw. A pull rod bushing is sleeved on the lead screw. The pull rod bushing moves back and forth along the length of the lead screw. One end of the pull rod bushing is fixedly connected to a lead screw nut on the lead screw. The other end of the pull rod bushing is connected to one end of a pull rod shaft. The other end of the pull rod shaft is provided with a touch control component for limiting the movement of the injection unit of the injection molding machine.

[0006] Furthermore, the touch component includes a pull rod connecting plate, a pull rod guide plate, and two nut guide rods. One end of the nut guide rod passes through the through hole of the pull rod connecting plate and is fixedly connected to the pull rod guide plate. A spring is sleeved on the nut guide rod, and the two ends of the spring abut against the inner side of the pull rod connecting plate and the pull rod guide plate, respectively. When the outer side of the pull rod connecting plate is subjected to the pressure of the head plate, it moves towards the pull rod guide plate. When the pressure of the head plate is removed, the pull rod connecting plate returns to its original position due to the elasticity of the spring.

[0007] Furthermore, the pull rod guide plate is equipped with two sensors, both of which are connected to the pull rod guide plate through a connecting plate. When the sensing block on the pull rod connecting plate moves toward the pull rod guide plate, one of the sensors detects the sensing block. When the sensing block continues to move, the other sensor detects the sensing block.

[0008] Furthermore, the sensing block is a U-shaped sensing block.

[0009] Furthermore, the pull rod guide plate has an opening in the center, and a stop block is provided on the inner wall of the opening. The stop block is adapted to the stop groove provided at the end of the pull rod shaft to prevent the pull rod guide plate and the pull rod shaft from rotating relative to each other.

[0010] Furthermore, one end of the pull rod bushing is connected to the lead screw nut via a rotary locking device to prevent the pull rod bushing and the lead screw nut from rotating relative to each other, and the other end of the pull rod bushing is detachably connected to the pull rod shaft via a connecting pin.

[0011] Furthermore, the rotary locking device includes a first limiting block, a second limiting block, and two crescent-shaped locking rings. The two crescent-shaped locking rings are engaged with each other in an annular groove located on the outer side of the end of the pull rod bushing. The annular groove has a corresponding slot, which is adapted to a locking block located on the inner side of the crescent-shaped locking ring to prevent the crescent-shaped locking ring from rotating relative to the pull rod bushing. The outer side of the crescent-shaped locking ring has a groove, which is adapted to a protrusion located on the inner side of the first limiting block to prevent the first limiting block from rotating relative to the crescent-shaped locking ring. The first limiting block and the second limiting block are fixedly connected.

[0012] Furthermore, the second limiting block is provided with a limiting groove on the side away from the first limiting block. This limiting groove is adapted to the end of the lead screw nut to prevent the second limiting block from rotating relative to the lead screw nut.

[0013] Furthermore, set screws are provided on both sides of the limiting groove, and the set screws are used to lock the second limiting block and the lead screw nut together.

[0014] Furthermore, the tie rod bushing has a hollow structure.

[0015] A tie rod mechanism for an injection seat of an injection molding machine according to the present invention has the following technical features and beneficial technical effects:

[0016] The tie rod mechanism of the injection seat of the injection molding machine of the present invention has a compact design, small overall size, high precision, fast response speed, high transmission efficiency, is applicable to a variety of injection molding machine models, and is easy to assemble, which helps to reduce assembly costs. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of the injection unit of the injection molding machine according to an embodiment of the present invention;

[0019] Figure 2 This is a partial structural diagram of the injection unit of an injection molding machine according to an embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the tie rod mechanism of the injection seat of the injection molding machine according to an embodiment of the present invention;

[0021] Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure;

[0022] Figure 5 This is an exploded structural diagram of the tie rod mechanism of the injection seat of the injection molding machine according to an embodiment of the present invention;

[0023] Figure 6 This is an exploded view of the touch component in the pull rod mechanism of the injection unit of the injection molding machine according to an embodiment of the present invention;

[0024] Figure 7 This is a partial structural schematic diagram of the tie rod mechanism of the injection seat of the injection molding machine according to an embodiment of the present invention;

[0025] Figure 8 for Figure 7 A schematic diagram of its decomposed structure. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention. It should be noted that the terms "front", "rear", "left", "right", "up" and "down" used in the following description refer to the directions in the accompanying drawings, and the terms "inner" and "outer" refer to the directions toward or away from the geometric center of a specific component, respectively.

[0028] Please see Figures 1 to 8 According to a preferred embodiment of the present invention, a pull rod mechanism for an injection unit of an injection molding machine is provided. The injection unit includes a base 100, a head plate 200 disposed on the base 100, and a linear guide rail 300. The linear guide rail 300 is a double linear guide rail. A slidable pull rod mechanism 400 is provided on the linear guide rail 300. The end of the pull rod mechanism 400 is connected to the head plate 200. An electric injection mechanism 500 is provided on the pull rod mechanism 400. When the pull rod mechanism 400 slides forward along the double linear guide rail, it drives the electric injection mechanism 500 to move forward toward the head plate 200 to realize injection. When the pull rod mechanism 400 slides backward along the double linear guide rail, it drives the electric injection mechanism 500 to move backward away from the head plate 200.

[0029] The pull rod mechanism 400 of the present invention includes an injection stage support 1. A motor 2 is fixedly mounted on one end of the injection stage support 1. The output shaft of the motor 2 is connected to one end of a lead screw 3. When the motor 2 is energized, it drives the lead screw 3 to rotate clockwise or counterclockwise. A pull rod bushing 4 is sleeved on the lead screw 3. The pull rod bushing 4 has a hollow structure. The pull rod bushing 4 moves back and forth along the length direction of the lead screw 3. One end of the pull rod bushing 4 is fixedly connected to a lead screw nut 5 provided on the lead screw 3. The other end of the pull rod bushing 4 is connected to one end of a pull rod shaft 6. The other end of the pull rod shaft 6 is provided with a touch control component 7 for limiting the movement of the injection seat of the injection molding machine. In use, motor 2 drives lead screw 3 to rotate, which in turn drives lead screw nut 5 to move forward or backward along the length of lead screw 3. Therefore, the linear transmission assembly formed by tie rod bushing 4 and tie rod shaft 6 drives touch control assembly 7 to move towards head plate 200. At the same time, electric injection mechanism 500, which is provided on tie rod mechanism 400, moves towards head plate 200 to inject glue. Compared with the traditional double-axis guided double-bearing tie rod device, tie rod mechanism 400 of the present invention has a simple structure, compact design, small overall size, strong load-bearing capacity, high precision, fast response speed, high transmission efficiency, applicability to various injection molding machine types, and convenient assembly, which helps to reduce assembly costs.

[0030] The touch component 7 of this embodiment includes a pull rod connecting plate 71, a pull rod guide plate 72, and two nut guide rods 73. Each nut guide rod 73 has a nut. One end of the nut guide rod 73, away from the nut, passes through a through hole in the pull rod connecting plate 71 and is fixedly connected to the pull rod guide plate 72. The outer diameter of the nut on the nut guide rod 73 is larger than the inner diameter of the through hole in the pull rod connecting plate 71. Therefore, the pull rod connecting plate 71 can move between the nut on the nut guide rod 73 and the pull rod guide plate 72. A spring 74 is sleeved on the nut guide rod 73. Both ends of the spring 74 abut against the inner sides of the pull rod connecting plate 71 and the pull rod guide plate 72, respectively. When the outer side of the pull rod connecting plate 71 is subjected to pressure generated by the interaction with the head plate 200, it moves towards the pull rod guide plate 72. When the pressure from the head plate 200 disappears, the pull rod connecting plate 71 returns to its original position due to the elastic action of the spring 74.

[0031] Two sensors 75 are provided on the pull rod guide plate 72. Preferably, the two sensors 75 are proximity sensors. Both sensors 75 are mounted on the same side of the pull rod guide plate 72 via a connecting plate 77, and the sensing surfaces of the two sensors 75 are offset from each other (i.e., the distances of the two sensors relative to the pull rod guide plate are not the same). When the sensing block 76 provided on the pull rod connecting plate 71 moves towards the pull rod guide plate 72, one of the sensors detects the sensing block 76. When the sensing block 76 continues to move, the other sensor detects the sensing block 76. Preferably, the sensing block 76 is a U-shaped sensing block for easy installation.

[0032] The pull rod guide plate 72 has an opening 721 in the center, and a stop block 722 is provided on the inner wall of the opening 721. The stop block 722 is adapted to the stop groove 61 provided at the end of the pull rod shaft 6 to prevent the pull rod guide plate 72 and the pull rod shaft 6 from rotating relative to each other.

[0033] Further explanation:

[0034] 1. During injection molding, the injection motor 501 of the electric injection mechanism 500 drives the injection stage 502 forward, and the nozzle 503 of the barrel is pushed into the injection port of the plastic mold (located on the head plate 200). The injection motor 501 continues to drive the injection stage 502 forward, the pull rod shaft 6 is subjected to force, the spring 74 of the touch component 7 is compressed, one of the sensors of the touch component 7 (preferably an inductive switch) is approached and sensed by the sensing stop 76, and the injection motor 501 stops driving the injection stage 502 forward. At this time, the contact force between the nozzle 503 and the plastic mold is equal to the compression force of the spring 74.

[0035] 2. During manual adjustment of injection molding, the injection motor 501 of the electric injection mechanism 500 drives the injection stage 502 forward. When the sensing block 76 approaches the second trigger sensor (preferably a sensor switch), the injection stage 502 is prevented from moving forward by the control system, thereby protecting the nozzle 503 of the electric injection mechanism 500 from damage by external force.

[0036] In this embodiment of the invention, one end of the pull rod bushing 4 is connected to the lead screw nut 5 via a rotary locking device 8 to prevent relative rotation between the pull rod bushing 4 and the lead screw nut 5, and the other end of the pull rod bushing 4 is detachably connected to the pull rod shaft 6 via a connecting pin 9.

[0037] The rotary locking device 8 includes a first limiting block 81, a second limiting block 82, and two crescent-shaped locking rings 83. The two locking rings 83 are engaged with each other within an annular groove 41 located on the outer side of the end of the pull rod bushing 4. The annular groove 41 has a corresponding slot 42, which engages with a locking block 831 located inside the locking ring 83 to prevent relative rotation between the crescent-shaped locking ring and the pull rod bushing. The outer side of the locking ring 83 has a groove 832, which engages with a protrusion 811 located inside the first limiting block 81 to prevent relative rotation between the first limiting block and the crescent-shaped locking ring. The first limiting block 81 and the second limiting block 82 are fixedly connected by bolts. In use, the pull rod bushing 4 exhibits good linear motion stability and is less prone to rotation, thus improving accuracy.

[0038] The second limiting block 82 has a limiting groove 821 on the side away from the first limiting block 81. The limiting groove 821 is adapted to the end of the lead screw nut 5 to prevent the second limiting block from rotating relative to the lead screw nut.

[0039] Set screws 10 are provided on both sides of the limiting groove 821. The set screws 10 are set screws and are used to lock the second limiting block 82 and the lead screw nut 5. In use, the second limiting block 82 and the lead screw nut 5 are firmly connected and not easy to loosen.

[0040] Further explanation: When motor 2 is working, it drives lead screw 3 to rotate clockwise or counterclockwise, and drives lead screw nut 5 to move forward or backward along the axis of lead screw 3. Since one end of pull rod bushing 4 is connected to lead screw nut 5 through rotary locking device 8, and the other end of pull rod bushing 4 is connected to pull rod shaft 6 through connecting pin 9, the use of connecting pin 9 facilitates quick assembly. Pull rod bushing 4 and pull rod shaft 6 move linearly synchronously with lead screw nut 5. Pull rod bushing 4 has a hollow structure and is sleeved on lead screw 3. In use, lead screw 3 rotates, and pull rod bushing 4, pull rod shaft 6 and lead screw nut 5 move linearly. To enhance the stability of linear motion, pull rod bushing 4 is connected to the launch platform support 1 through guide sleeve 11. That is, pull rod bushing 4 can slide along the inner ring of guide sleeve 11, and the outer ring of guide sleeve 11 is fixedly connected to launch platform support 1. Guide sleeve 11 is preferably made of copper.

[0041] A tie rod mechanism for an injection seat of an injection molding machine according to the present invention has the following technical features and beneficial technical effects:

[0042] The tie rod mechanism of the injection seat of the injection molding machine of the present invention has a compact design, small overall size, high precision, fast response speed, high transmission efficiency, is applicable to a variety of injection molding machine models, and is easy to assemble, which helps to reduce assembly costs.

[0043] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention 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 the invention or exceeding the scope defined by the appended claims.

Claims

1. A tie rod mechanism for an injection unit of an injection molding machine, the injection unit comprising a base, a head plate disposed on the base, and a linear guide rail, wherein a slidable tie rod mechanism is disposed on the linear guide rail, and the tie rod mechanism is connected to the head plate, characterized in that, The pull rod mechanism includes an injection table support, a motor is fixedly mounted on one end of the injection table support, the output shaft of the motor is connected to one end of the lead screw, a pull rod bushing is sleeved on the lead screw, the pull rod bushing moves back and forth along the length of the lead screw, one end of the pull rod bushing is fixedly connected to the lead screw nut on the lead screw, the other end of the pull rod bushing is connected to one end of the pull rod shaft, and the other end of the pull rod shaft is provided with a touch control component for limiting the movement of the injection seat of the injection molding machine; The touch component includes a pull rod connecting plate, a pull rod guide plate, and two nut guide rods. One end of the nut guide rod passes through the through hole of the pull rod connecting plate and is fixedly connected to the pull rod guide plate. A spring is sleeved on the nut guide rod, and the two ends of the spring abut against the inner side of the pull rod connecting plate and the pull rod guide plate, respectively. When the outer side of the pull rod connecting plate is subjected to pressure from the head plate, it moves towards the pull rod guide plate. When the pressure from the head plate is removed, the pull rod connecting plate returns to its original position due to the elasticity of the spring. The pull rod guide plate is equipped with two sensors, both of which are connected to the pull rod guide plate through a connecting plate. When the sensing block on the pull rod connecting plate moves toward the pull rod guide plate, one of the sensors detects the sensing block. When the sensing block continues to move, the other sensor detects the sensing block. The sensing block is a U-shaped sensing block, and the pull rod guide plate has an opening in the center, with a stop block on the inner wall of the opening.

2. The tie rod mechanism according to claim 1, characterized in that, The stop block is adapted to the stop groove located at the end of the tie rod shaft to prevent relative rotation between the tie rod guide plate and the tie rod shaft.

3. The tie rod mechanism according to claim 1, characterized in that, One end of the pull rod bushing is connected to the lead screw nut via a rotary locking device to prevent the pull rod bushing and the lead screw nut from rotating relative to each other. The other end of the pull rod bushing is detachably connected to the pull rod shaft via a connecting pin.

4. The tie rod mechanism according to claim 3, characterized in that, The rotary locking device includes a first limiting block, a second limiting block, and two crescent-shaped locking rings. The two crescent-shaped locking rings are engaged with each other in an annular groove located on the outer side of the end of the pull rod bushing. The annular groove has a corresponding slot, which is adapted to a locking block located on the inner side of the crescent-shaped locking ring to prevent the crescent-shaped locking ring from rotating relative to the pull rod bushing. The outer side of the crescent-shaped locking ring has a groove, which is adapted to a protrusion located on the inner side of the first limiting block to prevent the first limiting block from rotating relative to the crescent-shaped locking ring. The first limiting block and the second limiting block are fixedly connected.

5. The tie rod mechanism according to claim 4, characterized in that, The second limiting block has a limiting groove on the side away from the first limiting block. This limiting groove is adapted to the end of the lead screw nut to prevent the second limiting block from rotating relative to the lead screw nut.

6. The tie rod mechanism according to claim 5, characterized in that, Set screws are provided on both sides of the limiting groove. The set screws are used to lock the second limiting block and the lead screw nut.

7. The tie rod mechanism according to claim 3, characterized in that, The tie rod bushing has a hollow structure.

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