Nozzle protection structure of injection molding machine

Abstract

The present invention relates to the field of injection molding machines and discloses a novel nozzle protection structure of an injection molding machine, comprising a bracket protruding from one side of a head plate of the injection molding machine with a nozzle and a protective cover main body hingedly connected to the bracket, which leaves an avoidance space when flipped up and surrounds at least part of the nozzle when flipped down to prevent high-temperature molten material from splashing out. A ratchet is fixed to the upper end of the bracket, and a pawl is rotatably provided on the outer wall or the inner part of the protective cover main body, which limits the protective cover main body from falling back after cooperating with the ratchet. A spring is connected to the lower end of the pawl to drive the pawl to always cooperate with the ratchet. A lever extends downward from the end of the lower end of the pawl away from the ratchet, and an unlocking mechanism is provided on the protective cover main body to drive the lever to compress the spring and leave the ratchet. Through the protection structure of this scheme, the cost can be effectively reduced, the service life can be extended, and the safety hazard of the protective cover main body falling back quickly can be eliminated.

Description

Technical Field

[0001] The invention relates to the field of injection molding machines, and in particular to a nozzle protection structure of an injection molding machine. Background Art

[0002] Currently, injection molding machines are equipped with nozzle guards to prevent the splashing of hot molten material during injection, thereby ensuring personal safety. Nozzle guards are also required when cleaning the machine, replacing molds without retaining rings, changing nozzles, or performing equipment maintenance. At present, there are three types of nozzle protection devices that are widely used on the market: the first type is that the nozzle protection device is directly fixed on the fixed template, and the sheet metal of the nozzle protection cover on the operating side of the injection molding machine is made into an open door structure through a hinge; the second type is movable, and a circular hole is opened inside the nozzle protection cover and a slider is installed. The slider slides and opens and closes along two guide columns vertically fixed on the fixed template. The sliding mechanism can also be a roller, a linear bearing, or a built-in ball bearing. For example, the Chinese patent application number CN201711137479.3 discloses an injection molding machine nozzle protection structure using a linear ball bearing, which uses a linear ball bearing and a guide rod to realize the protection cover moving in the same direction or opposite direction along the injection nozzle; the third type is to install a protective cover base plate on the fixed template, and the base plate and the movable cover body are connected by a damping hinge or a non-damping hinge to realize the rotational movement of the protective cover along the rotation direction of the hinge.

[0003] The first structure mentioned above has the following problems: one side of the nozzle guard is made into a door-opening structure through a hinge. The guard door needs to be opened during operation. Since the guard hinge requires sufficient installation space, there will be insufficient avoidance space and inconvenient observation.

[0004] The second structure mentioned above has the following problems: the two guide columns vertically fixed on the fixed template are cantilever beam structures, which will cause insufficient avoidance space. In order to leave enough operation or maintenance space, sufficient length and rigidity are required, resulting in a significant increase in cost.

[0005] The third design, a flip-up nozzle guard, offers significant advantages over side-opening or removable nozzle guards, namely, it addresses the lack of clearance space encountered by the aforementioned two designs. However, it does have a significant disadvantage: the guard lacks an effective restraint during its return, posing an injury risk. Due to the guard's considerable weight, if an operator is working in the nozzle area after it's flipped up, someone accidentally bumping into the guard could cause it to fall back, potentially injuring the operator. Even if the operator fails to securely close the guard while flipping it back, they risk injuring themselves. While some companies have employed springs and dampers to slow the guard's return, the torque required to control the guard's free return is extremely high, and few hinges currently meet this requirement. These hinges are not only expensive but also inevitably degrade with repeated use. Furthermore, the constant high temperatures in the nozzle area can affect the hinge's performance. If the hinge fails, there's a risk of the guard falling back and injuring the operator. Summary of the Invention

[0006] In view of the shortcomings of the prior art in which the force of the flip nozzle guard is buffered by hinges and damping during its free fall, such as high cost and short service life, the present invention provides a nozzle protection structure for an injection molding machine, which can effectively extend the service life, reduce the cost and eliminate safety hazards.

[0007] In order to solve the above technical problems, the present invention is solved by the following technical solutions:

[0008] A nozzle protection structure for an injection molding machine includes a bracket protruding from one side of a head plate of the injection molding machine with a nozzle, and a protective cover main body hingedly connected to the bracket, which leaves an avoidance space when flipped up and surrounds at least part of the nozzle when flipped down to prevent high-temperature molten material from splashing out. A ratchet is fixed to the upper end of the bracket, and a pawl is rotatably provided on the outer wall or inside of the protective cover main body, which limits the protective cover main body from falling back after cooperating with the ratchet. A spring is connected to the lower end of the pawl to drive the pawl to always cooperate with the ratchet. A lever extends downward from the end of the lower end of the pawl away from the ratchet, and an unlocking mechanism is provided on the protective cover main body to drive the lever to compress the spring and leave the ratchet.

[0009] When the lever is unlocked, the pawl will be engaged with the ratchet, and the spring will release the pawl from the ratchet, causing the guard to stop falling. The above structure has the following advantages: 1. The locking structure of the ratchet pawl is a purely mechanical structure, which is not affected by high temperature and the number of times of use, and will not cause performance degradation, so that the service life of the structure is long; 2. The speed and degree of the fall of the protective cover body can be controlled at any time, which is safe and reliable and effectively reduces the probability of injury; 3. The spring used to control the pawl is only affected by the gravity of the pawl compared to the spring in the prior art, and the spring is in a natural state for a long time, which effectively extends the service life of the spring; 4. The ratchet, pawl and spring are all simple to process parts, which effectively reduce production costs compared to high-performance hinges.

[0010] Preferably, the unlocking mechanism includes a guide sleeve arranged on the outer wall or interior of the protective cover body and higher than the lever, a handle rotatably arranged on the protective cover body below the guide sleeve, and a cable fixed to the lever at one end and connected to the handle after passing through the guide sleeve at the other end. When the handle is turned, the cable pulls the lever to drive the pawl away from the ratchet. At this time, the protective cover body can be flipped downward.

[0011] With the above solution, the operator turns the handle, and the rotation of the handle drives the cable to pull the lever, and the rotation of the lever drives the pawl to compress the spring and leave the ratchet. At this time, the protective cover body can fall back downward. Once the operator lets go, the spring rebound will cause the pawl to engage with the ratchet again, and the protective cover body will stop falling back immediately. Even if the operator accidentally releases the handle, the protective cover body will not fall back quickly, which effectively increases the safety of operation.

[0012] Preferably, a bottom plate connected to the protective cover body is horizontally arranged below the pawl, and an adjustment mechanism for adjusting the spring elastic coefficient is arranged between the bottom plate and the pawl.

[0013] Preferably, the adjustment mechanism includes a through hole provided on the base plate, a threaded hole provided at the lower end of the pawl, and an adjustment screw which passes through the through hole and the spring in sequence and is connected to the threaded hole.

[0014] By adopting the above solution, the elastic coefficient of the spring can be adjusted by adjusting the position of the adjusting screw, thereby adjusting the matching state of the pawl and the ratchet wheel.

[0015] Preferably, the handle is a star-shaped handle for easy gripping.

[0016] With the above solution, the star-shaped handle is convenient for the operator to grasp and apply force.

[0017] Preferably, a perspective window is provided on one side or both sides of the protective cover body for facilitating observation of the interior of the protective cover body.

[0018] With the above solution, the provision of the perspective window makes it convenient for the operator to observe the working status of the nozzle located inside the protective cover.

[0019] Due to the adoption of the above technical scheme, the present invention has the following significant technical effects: 1. The protective cover body is locked to fall back through the cooperation of the ratchet and the pawl. The protective cover body can only be fallen back by the operator operating the unlocking mechanism. The speed and degree of the protective cover body falling back can be controlled at any time, which is safe and reliable and effectively reduces the probability of injury; 2. The ratchet and the pawl are purely mechanical mechanisms, which are not affected by high temperature and the number of times of use, and will not cause performance degradation, so that the service life of the structure is long; 3. The spring used to control the pawl is only affected by the gravity of the pawl compared to the spring in the prior art, and the spring is in a natural state for a long time, which effectively extends the service life of the spring; 4. The ratchet, pawl and spring are all simple-to-process parts, which effectively reduce production costs compared to high-performance hinges. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an axonometric view of a nozzle protection structure of an injection molding machine of the present invention when it is retracted and matched with the nozzle;

[0021] Figure 2 It is a partial cross-sectional view of a nozzle protection structure of an injection molding machine during a falling back process of the present invention;

[0022] Figure 3 yes Figure 2 A magnified view of middle A;

[0023] Figure 4 It is a partial cross-sectional view of a nozzle protection structure of an injection molding machine after being turned up in the present invention.

[0024] The names of the parts indicated by the numerical labels in the above drawings are as follows: 1. Head plate; 2. Nozzle; 3. Bracket; 4. Protective cover body; 5. Perspective window; 6. Hinge; 7. Ratchet; 8. Handle; 9. Positioning plate; 10. Guide sleeve; 11. Cable; 12. Mounting plate; 13. Base plate; 14. Pawl; 15. Spring; 16. Adjustment screw; 17. Lever. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below with reference to the accompanying drawings and embodiments. Example

[0026] A new nozzle 2 protection structure for injection molding machines, see Figure 1-Figure 4 As shown, it includes a bracket 3 protruding from one side of a nozzle 2 provided on a head plate 1 of an injection molding machine, and a protective cover main body 4 which is hinged to the bracket 3 through a hinge 6 and can leave an escape space when flipped up and surround at least part of the nozzle 2 when flipped down to prevent high-temperature molten material from splashing out. A perspective window 5 is provided on one side or both sides of the protective cover main body 4 for facilitating observation of the interior of the protective cover main body 4. The protective cover main body 4 is fitted with the bracket 3 after being flipped down.

[0027] Reference Figure 2-Figure 4 As shown, with specific reference to Figure 3 As shown, a ratchet 7 is welded and fixed on the upper end face of the bracket 3, and a pawl 14 is rotatably provided on the outer wall or inner part of the protective cover body 4 to limit the protective cover body 4 from falling back after cooperating with the ratchet 7. The pawl 14 is preferably arranged inside the protective cover body 4. In this embodiment, two mounting plates 12 extend downward and in parallel at the bottom of the upper end face of the protective cover body 4, and the pawl 14 is rotatably arranged between the two mounting plates 12. The lower ends of the two mounting plates 12 are connected to a base plate 13, and a spring 15 is connected between the base plate 13 and the side of the lower end of the pawl 14 close to the ratchet 7 to drive the pawl 14 to always cooperate with the ratchet 7. A lever 17 extends downward on the side of the lower end of the pawl 14 away from the ratchet 7, and an unlocking mechanism is provided on the protective cover body 4 to drive the lever 17 to compress the spring 15 and leave the ratchet 7.

[0028] The unlocking mechanism includes a guide sleeve 10 arranged on the outer wall or inside of the protective cover body 4 and higher than the lever 17, a handle 8 rotatably arranged below the guide sleeve 10 on the protective cover body 4, and a rope 11 with one end fixed to the lever 17 and the other end passing through the guide sleeve 10 and connected to the handle 8.

[0029] Since the pawl 14 is arranged inside the protective cover body 4, the guide sleeve 10 is preferably arranged inside the protective cover body 4. A positioning plate 9 is extended downward from the end of the upper end surface of the protective cover body 4 away from the bracket 3. The guide sleeve 10 is fixed between the positioning plate 9 and the side wall of the protective cover body 4. The handle 8 adopts a star-shaped handle 8. The end of the handle 8 away from the grip extends into the interior of the protective cover body 4 and is fixed with a screw on the end. The cable 11 is made of steel wire, and a through hole is provided on the lever 17. One end of the cable 11 passes through the through hole and is wound and fixed, and the other end passes around the guide sleeve 10 and is wound around the screw and fixed. Since the guide sleeve 10 is higher than the lever 17, after the handle 8 rotates and stores part of the cable 11, the lever 17 will cause the lever 17 to tilt up. At this time, the end of the pawl 14 away from the lever 17 is pressed down and leaves the ratchet 7, and the protective cover body 4 is in an unlocked state and can fall back downward.

[0030] An adjustment mechanism for adjusting the elastic coefficient of the spring 15 is provided between the base plate 13 and the pawl 14. The adjustment mechanism includes a through hole provided on the base plate 13, a threaded hole provided at the lower end of the pawl 14, and an adjustment screw 16 that passes through the through hole and the spring 15 in sequence and is connected to the threaded hole. By adjusting the position of the adjustment screw 16, the elastic coefficient of the spring 15 can be adjusted, thereby adjusting the coordination state of the pawl 14 and the ratchet 7. It is worth affirming that the production cost of the spring 15 in this scheme is significantly reduced compared with the prior art, and the service life is significantly increased. The reasons are as follows: when the spring 15 used in this scheme is reset, the maximum force it withstands is only the gravity of a pawl 14, which is about 0.1N, and the spring 15 is in a natural state for a long time. Only when the handle 8 is rotated will the spring 15 be temporarily compressed and deformed, and the compression amount is about 2mm. Therefore, both the compression amount and the force are far less than the rated value, which has basically no effect on the service life of the spring 15.

[0031] The cooperation between the pawl 14 and the ratchet 7 is a one-way limited cooperation, and the spring 15 of this solution drives the ratchet 7 to always be in a state of cooperation with the pawl 14 through elastic force. When the protective cover body 4 is turned up, the pawl 14 can move circumferentially relative to the ratchet 7. Conversely, when the protective cover body 4 wants to fall back, the pawl 14 will be stuck on the teeth of the ratchet 7 to limit the fall of the protective cover body 4. If you want the protective cover body 4 to fall back smoothly, you need to compress the spring 15 to make the pawl 14 disengage from the ratchet 7. Therefore, by turning the handle 8, the cable 11 is driven to pull The lever 17 rotates to drive the pawl 14 to compress the spring 15 and thus leave the ratchet 7. At this time, the protective cover body 4 can fall back. When the force pushing the lever 17 disappears, the pawl 14 will immediately be engaged with the ratchet 7 under the action of the spring 15, and the protective cover body 4 will immediately stop falling back. The falling back of the protective cover body 4 can only be achieved by the operator. Therefore, the setting of this scheme can control the speed and degree of the falling back of the protective cover body 4, thereby preventing the protective cover body 4 from falling back quickly and injuring the operator.

[0032] The above structure has the following significant advantages: 1. The locking structure of the ratchet 7 pawl 14 is a purely mechanical structure, which is not affected by high temperature and the number of times of use, and will not cause performance degradation, so that the service life of the structure is long; 2. The speed and degree of the fall of the protective cover body 4 can be controlled at any time, which is safe and reliable and effectively reduces the probability of injury; 3. The spring 15 used to control the pawl 14 is only affected by the gravity of the pawl 14 compared to the spring 15 in the prior art, and the spring 15 is in a natural state for a long time, which effectively extends the service life of the spring 15; 4. The ratchet 7, pawl 14 and spring 15 are all simply processed parts, which effectively reduce the production cost compared to the high-performance hinge 6.

[0033] Of course, the unlocking mechanism is not limited to the above structure, and any structure such as a gear, a lever, etc. that can cause the pawl 14 to disengage from the ratchet 7 can be applied here.

Claims

1. A nozzle protection structure for an injection molding machine, comprising a bracket (3) protruding from one side of a head plate (1) of the injection molding machine on which a nozzle (2) is provided, and a protective cover body (4) hingedly connected to the bracket (3) and arranged to leave an escape space when flipped up and surround at least part of the nozzle (2) when flipped down to prevent high-temperature molten material from splashing out, characterized in that: A ratchet (7) is fixed on the upper end of the bracket (3); a ratchet (14) is rotatably provided on the outer wall or the inner part of the protective cover body (4) for limiting the protective cover body (4) from falling back after cooperating with the ratchet (7); a spring (15) is connected to the lower end of the ratchet (14) for driving the ratchet (14) to always cooperate with the ratchet (7); a lever (17) is extended downward from the lower end of the ratchet (14) away from the ratchet (7); an unlocking mechanism is provided on the protective cover body (4) for driving the lever (17) to compress the spring (15) and leave the ratchet (7); the unlocking mechanism comprises a guide sleeve (10) provided on the outer wall or the inner part of the protective cover body (4) and higher than the lever (17); a spring (15) is rotatably provided on the protective cover body (4) below the guide sleeve (10); and a spring (15) is rotatably provided on the protective cover body (4) below the guide sleeve (10). A handle (8) is provided for rotation, and a cable (11) having one end fixed to a shifting rod (17) and the other end connected to the handle (8) after passing through a guide sleeve (10); a bottom plate (13) connected to a protective cover body (4) is provided horizontally below the ratchet (14); an adjusting mechanism for adjusting the elastic coefficient of a spring (15) is provided between the bottom plate (13) and the ratchet (14); the adjusting mechanism comprises a through hole provided on the bottom plate (13), a threaded hole provided at the lower end of the ratchet (14), and an adjusting screw (16) which passes through the through hole and the spring (15) in sequence and is connected to the threaded hole; when the handle (8) is rotated, the cable (11) pulls the shifting rod (17) to drive the ratchet (14) away from the ratchet wheel (7); at this time, the protective cover body (4) can be turned downward.

2. The nozzle protection structure of an injection molding machine according to claim 1, characterized in that: The handle (8) is a star-shaped handle (8) that is easy to grasp.

3. The nozzle protection structure of an injection molding machine according to claim 1, characterized in that: A perspective window (5) for facilitating observation of the interior of the protective cover body (4) is provided on one side or both sides of the protective cover body (4).

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