A piston rod fastening mechanism for an injection molding machine

Abstract

This utility model relates to the field of injection molding machine technology, specifically to a piston rod fastening mechanism for an injection molding machine. It includes a piston rod with a threaded head on one side. An annular groove is located in the center of the threaded head. A fastening assembly is threadedly connected to the threaded head. The fastening assembly includes a fastening block with a threaded hole in the center, which is threaded to the threaded head. Symmetrical locking pin grooves are located on both sides of the fastening block, and an arc-shaped retaining ring is movably inserted into each locking pin groove. The arc-shaped retaining ring is movably inserted into the annular groove. This utility model's piston rod fastening mechanism for an injection molding machine primarily utilizes an annular groove on the threaded head at one end of the piston rod. The fastening block on the fastening assembly is threaded to the threaded head. The fastening block is fixedly connected to the moving mold of the injection molding machine via a mounting plate. A first spring compresses the arc-shaped retaining ring, causing it to insert into the annular groove. The arc-shaped retaining ring fastens the threaded connection, effectively preventing loosening that can occur with prolonged use of a single threaded connection.

Description

Technical Field

[0001] This utility model relates to the field of injection molding machine technology, specifically to a piston rod fastening mechanism for injection molding machines. Background Technology

[0002] Injection molding machines are the main molding equipment used to make various shapes of plastic products from thermoplastic or thermosetting plastics using plastic molds. Its working principle is similar to that of a syringe. Through the thrust of a screw or plunger, the heated and plasticized molten plastic is injected into the closed mold cavity under certain pressure and speed. After cooling and solidification, the product is removed, completing one cycle. The piston rod is the core functional component of the injection molding machine. Its main function is to inject the molten plastic material in the barrel into the mold cavity at high pressure and high speed through the hydraulic system, and complete the product molding process in conjunction with the pressure holding and cooling process.

[0003] Chinese Patent CN219947034U discloses a pull-out piston rod device for injection molding machines, relating to the field of injection molding machine parts technology. Its key technical features include: a base with a feeding box on it; a feeding hopper on the top of the feeding box and a fixed mold on its side; the feeding hopper being connected to the molding cavity of the fixed mold; a moving mold slidably mounted on the base; a hydraulic cylinder on the base; a pull-out piston rod on the movable part of the hydraulic cylinder; the pull-out piston rod being connected to the moving mold; a support base on the base; a support tube on the support base; one end of the support tube being slidably connected to the pull-out piston rod; and a threaded cap on the other end of the support tube; the pull-out piston rod slidingly passing through the middle of the cap; a lubrication cavity on the inner wall of the support tube; an oil storage cotton inside the lubrication cavity; an oil inlet at the top of the lubrication cavity communicating with the outside; and several oil outlets at the bottom of the lubrication cavity, evenly distributed on the top of the inner wall of the support tube. This invention can automatically lubricate the pull-out piston rod and facilitate the cleaning of debris.

[0004] The piston rod and moving mold of small and medium-sized injection molding machines using the above-mentioned solutions and existing technologies usually rely on threaded connections. These connections are simple in structure and low in cost. However, after long-term use, the simple threaded connection is prone to loosening, which makes the thrust provided by the piston rod unstable and affects the injection molding process. Utility Model Content

[0005] The purpose of this invention is to provide a piston rod fastening mechanism for injection molding machines to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A piston rod fastening mechanism for an injection molding machine includes a piston rod, a threaded head on one side of the piston rod, an annular groove in the middle of the threaded head, a fastening assembly threadedly connected to the threaded head, a fastening block including a fastening block, a threaded hole in the middle of the fastening block, the threaded hole being threadedly connected to the threaded head, and symmetrical locking pin grooves on both sides of the fastening block, with an arc-shaped retaining ring block movably inserted into the locking pin groove, the arc-shaped retaining ring block being movably inserted into the annular groove.

[0007] Preferably, a lifting block is fixedly connected to one side of the arc-shaped retaining ring block, the lifting block is movably inserted into the retaining pin groove, and two sets of spring grooves are symmetrically provided on one side of the arc-shaped retaining ring block.

[0008] Preferably, the fastening block has two sets of threaded cap grooves symmetrically arranged on both sides, and a threaded rod cap is threadedly connected to one side of the threaded cap groove.

[0009] Preferably, the arc-shaped retaining ring block has a locking hole on one side, the fastening block is fixedly connected to the mounting block, and the fastening block has symmetrical locking pin grooves on both sides.

[0010] Preferably, a first spring is movably inserted into the threaded cap groove, with one side of the first spring movably inserted into the spring groove and the other side of the first spring pressing against the threaded rod cap.

[0011] Preferably, a locking pin is movably inserted into the locking pin slot, one side of the locking pin is inserted into the locking hole, the other side of the locking pin is fixedly connected to the lifting cap, one side of the lifting cap is fixedly connected to a second spring, and one side of the second spring is fixedly connected to the fastening block.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] The piston rod fastening mechanism for injection molding machines proposed in this utility model mainly involves setting an annular groove on the threaded head at one end of the piston rod, and connecting the fastening block on the fastening assembly to the threaded head. The fastening block is fixedly connected to the moving mold of the injection molding machine through a mounting plate. The arc-shaped retaining ring is squeezed by a first spring to insert into the annular groove. The arc-shaped retaining ring provides a fastening effect on the threaded connection, effectively avoiding the problem of loosening that occurs after prolonged use of a single threaded connection. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a piston rod fastening mechanism for an injection molding machine;

[0015] Figure 2 This is an exploded view of a partial structure of a piston rod fastening mechanism for an injection molding machine.

[0016] Figure 3This is a partial structural cross-sectional view of a piston rod fastening mechanism for an injection molding machine;

[0017] Figure 4 for Figure 3 Enlarged view of the middle section;

[0018] Figure 5 This is a partial structural diagram of a piston rod fastening mechanism for an injection molding machine.

[0019] In the diagram: Piston rod 1, threaded head 2, annular groove 3, fastening block 401, threaded hole 402, locking pin groove 403, arc-shaped retaining ring block 404, lifting block 405, spring groove 406, threaded cap groove 407, threaded rod cap 408, first spring 409, locking hole 410, locking pin groove 411, locking pin 412, lifting cap 413, second spring 414, mounting block 415. Detailed Implementation

[0020] The technical solutions in the embodiments of this utility model will be clearly and completely described below. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] Please see Figures 1 to 5 This utility model provides the following two technical solutions:

[0022] Example 1: A piston rod fastening mechanism for an injection molding machine includes a piston rod 1. A threaded head 2 is provided on one side of the piston rod 1. An annular groove 3 is provided in the middle of the threaded head 2. A fastening assembly is threadedly connected to the threaded head 2. The fastening assembly includes a fastening block 401. A threaded hole 402 is provided in the middle of the fastening block 401, which is threadedly connected to the threaded head 2. Retaining pin grooves 403 are symmetrically provided on both sides of the fastening block 401. An arc-shaped retaining ring block 404 is movably inserted into the retaining pin groove 403 and is movably inserted into the annular groove 3. A lifting block 405 is fixedly connected to one side of the arc-shaped retaining ring block 404. 5. The retaining ring block 404 is symmetrically provided with two sets of spring grooves 406 on one side; the fastening block 401 is symmetrically provided with two sets of threaded cap grooves 407 on both sides, and a threaded rod cap 408 is threadedly connected to one side of the threaded cap groove 407; the retaining ring block 404 is provided with a locking hole 410 on one side, the fastening block 401 is fixedly connected with an installation block 415, and the fastening block 401 is symmetrically provided with locking pin grooves 411 on both sides; a first spring 409 is movably inserted into the threaded cap groove 407, one side of the first spring 409 is movably inserted into the spring groove 406, and the other side of the first spring 409 is pressed against the threaded rod cap 408.

[0023] In use, the piston rod 1 on one side of the cylinder is threaded to the fastening block 401 of the fastening assembly via a threaded head 2. The fastening block 401 has a threaded hole 402 in the middle, which is threaded to the threaded head 2. The diameter of the threaded head 2 is smaller than the diameter of the piston rod 1, so that the fastening block 401 has a limiting effect when it is threaded to the threaded head 2. When the fastening block 401 is limited and cannot be turned, the annular groove 3 in the middle of the threaded head 2 is exactly aligned with the locking pin grooves 403 on both sides of the fastening block 401. The fastening block 401 has threaded cap grooves 407 on both sides. The first spring 409 is inserted into the threaded cap groove 407. One side of the first spring 409 falls into the spring groove 406 on the arc-shaped retaining ring block 404, and the other side of the first spring 409 is in the threaded cap groove 407. Then the threaded rod cap 408 is screwed on. Within the threaded cap groove 407, the threaded rod cap 408 exerts a squeezing action on the first spring 409. In its natural state, the first spring 409 will squeeze the arc-shaped retaining ring block 404 into the annular retaining groove 3, thus securing the threaded connection between the fastening block 401 and the threaded head 2 on the piston rod 1. Before tightening the threaded head 2 of the fastening block 401 each time, the lifting block 405 on one side of the arc-shaped retaining ring block 404 must be pulled up first. The lifting block 405 drives the arc-shaped retaining ring block 404 to disengage from the threaded hole 402, so as not to affect the screwing in of the fastening block 401. The fastening block 401 is fixedly connected to the surrounding area of ​​the mounting block 415. The fastening block 401 can be connected to the moving mold mechanism of the injection molding machine through the mounting block 415, realizing the connection between the piston rod 1 and the moving mold mechanism of the injection molding machine. The piston rod can stably transmit thrust to the moving mold mechanism to compress the product.

[0024] Example 2: Based on Example 1, a locking pin 412 is movably inserted into the locking pin slot 411. One side of the locking pin 412 is inserted into the locking hole 410, and the other side of the locking pin 412 is fixedly connected to the lifting cap 413. A second spring 414 is fixedly connected to one side of the lifting cap 413, and one side of the second spring 414 is fixedly connected to the fastening block 401.

[0025] In use, the fastening block 401 has symmetrical locking pin grooves 411 on both sides, and a locking pin 412 is movably inserted into the locking pin groove 411. A lifting cap 413 is fixedly connected to one side of the locking pin 412. Before the fastening block 401 is screwed into the threaded head 2, when the lifting block 405 is lifted, since the lifting cap 413 is connected to the second spring 414, and the second spring 414 is connected to the fastening block 401, in the natural state, the second spring 414 presses the locking pin 412, so the locking pin 412 is constantly pressed against the lifting block 405. When lifted to a certain height, the locking pin 412 is pressed into the locking hole 410 on one side of the lifting block 405, at which point the lifting block 405 is locked. With the connection fixed, the arc-shaped retaining ring block 404 is also in the state of being disengaged from the threaded hole 402 and the annular groove 3. After tightening the fastening block 401, pull up the lifting cap 413 on one side of the locking pin 412, causing the locking pin 412 to disengage from the locking hole 410. The lifting block 405 is released from lock. Under the squeezing action of the first spring 409, the lifting block 405 drives the arc-shaped retaining ring block 404 to squeeze into the annular groove 3. The two sets of symmetrical arc-shaped retaining ring blocks 404 play a limiting role in preventing the threads of the fastening block 401 from loosening. No matter how long it is used or mechanical vibration, the fastening block 401 and the piston rod 1 will not become loose, which also allows the piston rod 1 to provide stable power to the injection molding machine mechanism.

[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A piston rod fastening mechanism for an injection molding machine, comprising a piston rod (1), characterized in that: The piston rod (1) has a threaded head (2) on one side, and an annular groove (3) in the middle of the threaded head (2). The threaded head (2) is threadedly connected to a fastening assembly, which includes a fastening block (401). The fastening block (401) has a threaded hole (402) in the middle, which is threadedly connected to the threaded head (2). The fastening block (401) has symmetrical locking pin grooves (403) on both sides. An arc-shaped retaining ring block (404) is movably inserted into the retaining pin groove (403). The arc-shaped retaining ring block (404) is movably inserted into the annular groove (3).

2. A piston rod fastening mechanism for an injection molding machine according to claim 1, characterized in that: A lifting block (405) is fixedly connected to one side of the arc-shaped retaining ring block (404), and the lifting block (405) is movably inserted into the retaining pin groove (403). Two sets of spring grooves (406) are symmetrically provided on one side of the arc-shaped retaining ring block (404).

3. A piston rod fastening mechanism for an injection molding machine according to claim 1, characterized in that: The fastening block (401) has two sets of threaded cap grooves (407) symmetrically arranged on both sides, and a threaded rod cap (408) is threadedly connected to one side of the threaded cap groove (407).

4. The piston rod fastening mechanism for an injection molding machine according to claim 1, characterized in that: The arc-shaped retaining ring block (404) has a locking hole (410) on one side, the fastening block (401) is fixedly connected to the mounting block (415), and the fastening block (401) has symmetrical locking pin grooves (411) on both sides.

5. The piston rod fastening mechanism for an injection molding machine according to claim 3, characterized in that: A first spring (409) is movably inserted into the threaded cap groove (407). One side of the first spring (409) is movably inserted into the spring groove (406), and the other side of the first spring (409) is pressed against the threaded rod cap (408).

6. The piston rod fastening mechanism for an injection molding machine according to claim 4, characterized in that: The locking pin slot (411) is movably connected to a locking pin (412). One side of the locking pin (412) is inserted into the locking hole (410), and the other side of the locking pin (412) is fixedly connected to the lifting cap (413). One side of the lifting cap (413) is fixedly connected to a second spring (414), and one side of the second spring (414) is fixedly connected to the fastening block (401).

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