Single-cylinder injection device and injection molding machine thereof

Abstract

The utility model discloses a single-cylinder injection device and an injection molding machine thereof. The single-cylinder injection device comprises a single glue injection oil cylinder, a glue melting component, a hydraulic motor, an injection pedestal, a first linear guide rail, a rack, a second linear guide rail and an injection moving oil cylinder, according to the utility model, an external glue pumping oil cylinder is omitted, so that the number of parts is reduced, and the installation operation is simplified; the axial length of the injection pedestal is effectively shortened, the longitudinal span of supporting points is shortened, and the supporting rigidity of the injection pedestal is effectively improved; the length of the second linear guide rail is reserved, so that on the premise that the rack is not repaired, the screw rod length meeting different production requirements can be met, and the position of the injection device can be adjusted.

Description

Technical Field

[0001] The utility model relates to the field of injection molding, in particular to a single-cylinder injection molding device and an injection molding machine comprising the single-cylinder injection molding device. Background Art

[0002] The injection device is one of the important core components of the injection molding machine. Its function is to drive the screw to rotate and make reciprocating linear motion. Its performance will directly affect the precision, repeatability and energy consumption of the product. In traditional technology, two parallel double-acting injection cylinders are generally arranged (that is, the injection cylinder realizes the injection and extraction functions at the same time) to realize the reciprocating motion of the screw; due to the limitation of injection force, it is necessary to ensure sufficient injection force, and the cylinder area is generally set to be relatively large. In this way, the amount of oil return from injection is large, which leads to increased energy consumption, slow response and slow injection speed (similar prior art can refer to the background technology part and the attached drawings of the specification of a multi-cylinder combined injection device with announcement number CN209022399U). There is another traditional technology, which has two external extraction cylinders to drive the screw backward, and a injection cylinder is arranged in the middle to drive the screw forward to realize reciprocating motion. This structure has many parts and a long axial dimension, more parts to be processed and complex assembly.

[0003] In addition to driving the screw to perform reciprocating linear motion, the injection device as a whole also needs to perform reciprocating linear motion to move the molten plastic part closer to or away from the injection mold; therefore, the total movement stroke of the injection device is the sum of the injection stroke and the injection displacement stroke. The traditional technology is to arrange one or two injection displacement cylinders to drive the injection device to move. A shooting platform fixedly connected to the frame is provided under the injection device, so the length of the shooting platform is directly related to the size of the two strokes (similar prior art can refer to the announcement number CN209022397U, a single-cylinder injection device with an external glue extraction cylinder). For injection devices with larger strokes, the axial size of the shooting platform also increases, resulting in a decrease in support rigidity. In addition, since the shooting platform is fixed on the frame, screws of different lengths can only be used when the frame is repaired, and it cannot flexibly adapt to production needs. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, one of the purposes of the utility model is to provide a single-cylinder injection device, and the second purpose is to provide an injection molding machine including such a single-cylinder injection device, which can solve the problems of large oil return resistance, complex structure and low support rigidity existing in the existing injection device.

[0005] The utility model is realized by the following technical solutions:

[0006] A single-cylinder injection device comprises: a single injection cylinder, which is a double-acting cylinder; a melt-melting component, which is fixedly connected to the injection cylinder so as to be driven by the injection cylinder to rotate and reciprocate linearly; the melt-melting component and the injection cylinder are arranged in a coaxial direction; a hydraulic motor, which is fixedly connected to the rear end of the injection cylinder; a shooting platform seat, the injection cylinder is fixed to the top of the shooting platform seat; a first linear guide rail, which is fixed to the top of the shooting platform seat; the hydraulic motor is fixed to the slider of the first linear guide rail; a frame; a second linear guide rail, which is fixed to the top of the frame; the bottom of the shooting platform seat is fixed to the slider of the second linear guide rail; and a shooting displacement cylinder, one end of which is fixed to a fixed mold plate, and the other end is relatively fixed to the shooting platform seat.

[0007] Furthermore, the single-cylinder injection device also includes a hydraulic motor flange; the hydraulic motor is fixed in the hydraulic motor flange, and the hydraulic motor flange is fixedly mounted on the slider of the first linear guide rail.

[0008] Furthermore, the injection molding oil cylinder comprises: an injection molding oil cylinder body, and a first injection molding piston rod, a second injection molding piston rod and an integrated transmission shaft arranged in the injection molding oil cylinder body; two ends of the integrated transmission shaft are respectively fixed to the melting molding component and the hydraulic motor, so that the rotational motion output by the hydraulic motor is transmitted to the melting molding component through the integrated transmission shaft; two ends of the first injection molding piston rod are respectively fixed to the melting molding component and the second injection molding piston rod, and the melting molding component, the first injection molding piston rod and the second injection molding piston rod are coaxially arranged, so that the injection molding oil cylinder drives the melting molding component to make axial reciprocating movement.

[0009] Furthermore, the first injection-molding piston rod and the second injection-molding piston rod are each provided with a through inner hole, and rolling bearings are installed on the inner walls of the two through inner holes. The integrated transmission shaft is passed through the rolling bearings so that the integrated transmission shaft can be rotatably connected to the first injection-molding piston rod and the second injection-molding piston rod.

[0010] Furthermore, the injection molding oil cylinder also includes: an injection molding oil cylinder front cover and an injection molding oil cylinder rear cover respectively fixedly installed on the front and rear sides of the injection molding oil cylinder body; the injection molding oil cylinder front cover and the injection molding oil cylinder rear cover are both provided with an oil inlet; the injection molding oil cylinder also includes a shooting platform front plate, the shooting platform front plate is sleeved on the injection molding oil cylinder body, the injection molding oil cylinder front cover and the injection molding oil cylinder rear cover are simultaneously fixed to the front and rear sides of the shooting platform front plate; one end of the injection cylinder is fixedly connected to the shooting platform front plate, and the shooting platform front plate is fixedly connected to the shooting platform seat.

[0011] Furthermore, a limiting step is protruded from the front plate of the shooting platform; when the first shooting piston rod moves forward to the maximum injection position, the first shooting piston rod abuts against the limiting step to achieve axial limiting, and at the same time, there is a gap between the hydraulic motor flange and the rear cover of the shooting cylinder.

[0012] Furthermore, after the front plate of the shooting platform is assembled to the injection cylinder body, a convex positioning surface is formed, and abuts against the rear cover of the injection cylinder, so that there is a gap between the front plate of the shooting platform and the rear cover of the injection cylinder.

[0013] Furthermore, a waste oil tank is arranged at the bottom of the front cover of the injection cylinder. The waste oil tank has a cavity for collecting waste oil, and the top of the cavity has an opening.

[0014] Furthermore, a positioning pin is provided on the shooting platform seat, and a pin hole is correspondingly provided on the injection molding oil cylinder; the injection molding oil cylinder is fixedly connected to the shooting platform seat through the positioning pin and the fastening screw, so that the injection molding oil cylinder drives the shooting platform seat to slide along the second linear guide rail.

[0015] An injection molding machine, characterized in that the injection molding machine comprises any one of the single-cylinder injection devices described.

[0016] Compared with the prior art, the utility model can achieve the following beneficial effects:

[0017] (1) The utility model eliminates two double-acting injection cylinders arranged in parallel, and adopts a double-acting single-cylinder injection structure coaxial with the melt component, which makes the injection and extraction actions smoother. During injection, since a single-cylinder injection is adopted, the oil discharge volume of the return oil chamber is reduced, so that the return oil resistance of the injection action is reduced, the injection response is faster, and the injection speed is higher; during extraction, since the oil chamber volume is small, the extraction action is faster at the same flow rate. At the same time, compared with the single-cylinder injection unit with an external glue extraction cylinder, the utility model eliminates the external glue extraction cylinder, reduces the number of parts, and simplifies the installation operation.

[0018] (2) In the past, the axial length of the shooting platform seat had to be greater than the sum of the injection stroke and the injection displacement stroke. In the present utility model, a first linear guide is provided on the shooting platform seat, and the injection cylinder is slidably arranged on the first linear guide, which is equivalent to guiding the injection stroke through the first linear guide; at the same time, a second linear guide is provided on the frame, and the shooting platform seat is slidably arranged on the second linear guide, which is equivalent to guiding the injection displacement stroke through the second linear guide. In this way, the injection stroke and the injection displacement stroke are arranged in parallel, and the injection displacement stroke is transferred to the bottom of the shooting platform seat, thereby effectively shortening the axial length of the shooting platform seat, shortening the longitudinal span of the support point, and effectively improving the support rigidity of the shooting platform seat.

[0019] (3) A second linear guide is provided on the frame, so that the entire injection unit can be moved on the frame. By reserving the length of the second linear guide, the screw length required for different production needs can be met and the position of the injection device can be adjusted without re-repairing the frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Shown is a side view of the utility model;

[0021] Figure 2 Shown Figure 1 sectional view of .

[0022] In the figure: 10, injection cylinder; 11, injection cylinder body; 12, first injection piston rod; 13, second injection piston rod; 14, integrated transmission shaft; 15, injection cylinder front cover; 16, injection cylinder rear cover; 17, shooting platform front plate; 18, limit step; 19, positioning surface; 110, waste oil tank; 20, melt-melting component; 30, hydraulic motor; 40, shooting platform seat; 41, positioning pin; 50, first linear guide; 60, frame; 70, second linear guide; 80, injection cylinder; 90, fixed plate; 100, hydraulic motor flange. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0024] In the description of the present invention, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0026] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0027] The utility model discloses a single-cylinder injection device, which is used on an injection molding machine. Figure 1-Figure 2 The utility model at least comprises: a single injection cylinder 10, a melt-melting component 20, a hydraulic motor 30, a shooting platform 40, a first linear guide rail 50, a frame 60, a second linear guide rail 70 and an injection cylinder 80.

[0028] Among them, the injection cylinder 10 is a double-acting cylinder that can simultaneously realize the functions of injection and extraction. The melt component 20 is fixedly connected to the injection cylinder 10 and arranged coaxially with the injection cylinder 10. The melt component 20 is driven by the injection cylinder 10 to rotate and reciprocate linearly, thereby injecting and spirally pushing the molten material into the fixed mold plate 90. The hydraulic motor 30 is fixed at the rear end of the injection cylinder 10, and is used to output a rotational torque for the injection cylinder 10 and drive the melt component 20 to rotate. Of course, in other embodiments, the hydraulic motor 30 can also be other known rotation drive sources, such as a motor.

[0029] In particular, the injection cylinder 10 is fixed on the top of the injection platform 40, the first linear guide 50 is fixed on the top of the injection platform 40 and is located at the rear side of the injection cylinder 10, and the hydraulic motor 30 is relatively fixed to the slider of the first linear guide 50, so that during the injection and extraction process, the hydraulic motor 30 slides along the first linear guide 50. At the same time, the second linear guide 70 is fixed on the top of the frame 60, and the bottom of the injection platform 40 is fixed on the slider of the second linear guide 70. One end of the injection cylinder 80 is fixed to the fixed mold plate 90, and the other end is relatively fixed to the injection platform 40, so that during the injection process, the injection platform 40 slides along the second linear guide 70.

[0030] Compared with the prior art, the utility model has the following technical effects:

[0031] (1) The present invention eliminates the two parallel double-acting injection cylinders 10 and adopts a double-acting single-cylinder injection structure coaxial with the melt component 20, which makes the injection and extraction of glue smoother. During injection, since a single-cylinder injection is used, the oil discharge volume of the return oil chamber is reduced, so that the return oil resistance of the injection action is reduced, the injection response is faster, and the injection speed is higher; during extraction, since the oil chamber volume is small, the extraction action is faster at the same flow rate. At the same time, compared with the single-cylinder injection unit with an external glue extraction cylinder, the present invention eliminates the external glue extraction cylinder, reduces the number of parts, and simplifies the installation operation.

[0032] (2) In the past, the axial length of the shooting platform 40 had to be greater than the sum of the injection stroke and the injection displacement stroke. In the present invention, a first linear guide 50 is provided on the shooting platform 40, and the injection cylinder 10 is slidably disposed on the first linear guide 50, which is equivalent to guiding the injection stroke through the first linear guide 50; at the same time, a second linear guide 70 is provided on the frame 60, and the shooting platform 40 is slidably disposed on the second linear guide 70, which is equivalent to guiding the injection displacement stroke through the second linear guide 70. In this way, the injection stroke and the injection displacement stroke are arranged in parallel, and the injection displacement stroke is transferred to the bottom of the shooting platform 40, thereby effectively shortening the axial length of the shooting platform 40, shortening the longitudinal span of the support point, and effectively improving the support rigidity of the shooting platform 40.

[0033] (3) The second linear guide 70 is provided on the frame 60, so that the entire injection unit can be moved on the frame 60. By reserving the length of the second linear guide 70, the screw length required for different production needs can be met and the position of the injection device can be adjusted without re-repairing the frame 60.

[0034] Specifically, the utility model further includes a hydraulic motor flange 100 as a connecting piece of the hydraulic motor 30. The hydraulic motor 30 is fixed in the hydraulic motor flange 100, and the hydraulic motor flange 100 is fixedly mounted on the slider of the first linear guide rail 50. During the process of injection or extraction of glue, the hydraulic motor flange 100 slides along the first linear guide rail 50.

[0035] Specifically, the injection cylinder 10 includes: an injection cylinder body 11, a first injection piston rod 12, a second injection piston rod 13 and an integrated transmission shaft 14. The two ends of the integrated transmission shaft 14 are respectively fixedly connected to the melt-molding component 20 and the hydraulic motor 30, so that the rotational motion output by the hydraulic motor 30 is transmitted to the melt-molding component 20 through the integrated transmission shaft 14, thereby driving the melt-molding component 20 to rotate. More specifically, the rear end of the integrated transmission shaft 14 is processed with a connection key matching the hydraulic motor 30, and the front end thereof is connected to the melt-molding component 20 through two flat keys, so that the torque of the hydraulic motor 30 is directly transmitted to the melt-molding component 20, reducing the connection links.

[0036] At the same time, both ends of the first injection piston rod 12 are respectively fixed to the melt glue component 20 and the second injection piston rod 13, and the melt glue component 20, the first injection piston rod 12, and the second injection piston rod 13 are coaxially arranged, so that the injection cylinder 10 can drive the melt glue component 20 to perform axial reciprocating movement through the injection piston rod.

[0037] More specifically, through inner holes are provided in the first injection piston rod 12 and the second injection piston rod 13, and rolling bearings are installed on the inner walls of the two through inner holes, and the integrated transmission shaft 14 is inserted into the rolling bearings, so that the integrated transmission shaft 14 is rotatably installed in the first injection piston rod 12 and the second injection piston rod 13. In other words, the integrated transmission shaft 14 is inserted into the inside of the two injection piston rods, and the integrated transmission shaft 14 and the two injection piston rods are axially and radially positioned by the rolling bearings, so that the injection piston rods and the transmission shaft move as a whole when the entire device moves axially; at the same time, the first injection piston rod 12 and the second injection piston rod 13 do not follow the integrated transmission shaft 14 to make rotational movement, and the axial movement and rotational movement of the melt component 20 do not interfere with each other.

[0038] More specifically, the first injection piston rod 12 has a large head end and a small head end, and the inner hole of the large head end is provided with a positioning circle which matches with the boss on the second injection piston rod 13 and is connected by bolts, so as to realize the mutual fixation of the first injection piston rod 12 and the second injection piston rod 13. The diameter of the small head end of the first injection piston rod 12 is not affected by the injection force requirements, and the diameter of the small head end of the first injection piston rod 12 can be designed according to the actual requirements of the extraction action, so as to control the oil return amount of the oil return chamber during injection, realize a low injection oil return ratio, and improve the efficiency of injection and extraction.

[0039] Specifically, the injection cylinder 10 further includes: an injection cylinder front cover 15 and an injection cylinder rear cover 16 respectively fixedly mounted on the front and rear sides of the injection cylinder body 11. Both the injection cylinder front cover 15 and the injection cylinder rear cover 16 are provided with an oil inlet; the injection cylinder 10 further includes a shooting platform front plate 17, which is sleeved outside the injection cylinder body 11, and the injection cylinder front cover 15 and the injection cylinder rear cover 16 are simultaneously fixed to the front and rear sides of the shooting platform front plate 17; one end of the injection cylinder 80 is fixedly connected to the shooting platform front plate 17, and the shooting platform front plate 17 is fixedly connected to the shooting platform seat 40.

[0040] When injecting glue, oil is introduced through the injection cylinder rear cover 16 and returned through the injection cylinder front cover 15 to realize the injection action; when drawing glue, oil is introduced through the injection cylinder front cover 15 and returned through the injection cylinder rear cover 16 to realize the drawing action. In this way, the reciprocating linear motion of the screw is realized, and the injection cylinder 10 and the melt component 20 are coaxial, the movement of the injection cylinder 10 will not be eccentric, and the action is more stable and reliable.

[0041] Specifically, a limiting step 18 is convexly provided on the front plate 17 of the shooting platform; when the first injection piston rod 12 moves forward to the maximum injection position, the first injection piston rod 12 abuts against the limiting step 18 to achieve axial limitation, thereby limiting further displacement of the injection piston rod in the cylinder; at the same time, a gap is provided between the hydraulic motor flange 100 and the injection cylinder rear cover 16, thereby avoiding the risk of bolt breakage of the hydraulic motor 30 and improving the reliability of the injection device.

[0042] Specifically, after the shooting platform front plate 17 is assembled to the injection cylinder body 11 , a convex positioning surface 19 is formed, and abuts against the injection cylinder rear cover 16 , so that there is a gap between the shooting platform front plate 17 and the injection cylinder rear cover 16 .

[0043] Specifically, a waste oil tank 110 is arranged at the bottom of the front cover 15 of the injection cylinder. The waste oil tank 110 has a cavity for collecting waste oil, and the top of the cavity is open. The function of the waste oil tank 110 is that when the first injection piston rod 12 reciprocates, the oil scraped by the seal is stored in the seal groove for a long time, which will cause oil dripping. The waste oil tank 110 is used to store the oil scraped by the dust ring, so as to achieve the purpose of collecting waste oil in a centralized manner.

[0044] Specifically, a positioning pin 41 is provided on the shooting platform seat 40, and a pin hole is correspondingly provided on the injection molding cylinder 10; the injection molding cylinder 10 is fixedly connected to the shooting platform seat 40 through the positioning pin 41 and the fastening screw, so that when the injection molding cylinder 80 is actuated, it can drive the shooting platform seat 40 to slide along the second linear guide rail 70.

[0045] The utility model also discloses an injection molding machine, comprising any of the above-mentioned single-cylinder injection devices. Any injection molding machine using the same or substantially the same single-cylinder injection device should be within the protection scope of the utility model.

[0046] The above-mentioned implementation modes are only preferred implementation modes of the present invention, and cannot be used to limit the protection scope of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A single-cylinder injection device, characterized in that: include: A single injection cylinder, which is a double-acting cylinder; The melt-melting component is fixedly connected to the injection cylinder to be driven by the injection cylinder to perform rotation and linear reciprocating motion; the melt-melting component and the injection cylinder are arranged in a coaxial direction; A hydraulic motor is fixedly connected to the rear end of the injection cylinder; A shooting platform seat, the injection cylinder is fixed on the top of the shooting platform seat; A first linear guide rail is fixed to the top of the shooting platform; The hydraulic motor is fixed on the slider of the first linear guide rail; frame; A second linear guide rail is fixed to the top of the frame; the bottom of the shooting platform is fixed to the slider of the second linear guide rail; The shooting oil cylinder has one end fixed to the fixed template and the other end relatively fixed to the shooting platform seat.

2. The single-cylinder injection device according to claim 1, characterized in that: The single-cylinder injection device further comprises a hydraulic motor flange; the hydraulic motor is fixed in the hydraulic motor flange, and the hydraulic motor flange is fixedly mounted on a slider of the first linear guide rail.

3. The single-cylinder injection device according to claim 2, characterized in that: The injection cylinder comprises: an injection cylinder body, and a first injection piston rod, a second injection piston rod and an integrated transmission shaft arranged in the injection cylinder body; Two ends of the integrated transmission shaft are respectively fixed to the melt-adhesive component and the hydraulic motor, so that the rotational motion output by the hydraulic motor is transmitted to the melt-adhesive component through the integrated transmission shaft; The two ends of the first injection piston rod are respectively fixed to the melt-molding component and the second injection piston rod. The melt-molding component, the first injection piston rod and the second injection piston rod are coaxially arranged so that the injection cylinder drives the melt-molding component to perform axial reciprocating movement.

4. The single-cylinder injection device according to claim 3, characterized in that: The first injection-molding piston rod and the second injection-molding piston rod are each provided with a through inner hole, and rolling bearings are installed on the inner walls of the two through inner holes. The integrated transmission shaft is passed through the rolling bearings so that the integrated transmission shaft can be rotatably connected to the first injection-molding piston rod and the second injection-molding piston rod.

5. The single-cylinder injection device according to claim 3, characterized in that: The injection cylinder further comprises: an injection cylinder front cover and an injection cylinder rear cover respectively fixedly mounted on the front and rear sides of the injection cylinder body; the injection cylinder front cover and the injection cylinder rear cover are both provided with an oil inlet; The injection molding oil cylinder further comprises an injection platform front plate, which is sleeved on the outside of the injection molding oil cylinder body, and the injection molding oil cylinder front cover and the injection molding oil cylinder rear cover are simultaneously fixed to the front and rear sides of the injection platform front plate; One end of the shooting oil cylinder is fixedly connected to the front plate of the shooting platform, and the front plate of the shooting platform is fixedly connected to the shooting platform seat.

6. The single-cylinder injection device according to claim 5, characterized in that: The front plate of the shooting platform is also provided with a limiting step; When the first injection piston rod moves forward to the maximum injection position, the first injection piston rod abuts against the limiting step to achieve axial limiting, and at the same time, a gap exists between the hydraulic motor flange and the injection cylinder rear cover.

7. The single-cylinder injection device according to claim 5, characterized in that: After the front plate of the shooting platform is assembled to the injection cylinder body, a convex positioning surface is formed, and abuts against the rear cover of the injection cylinder, so that there is a gap between the front plate of the shooting platform and the rear cover of the injection cylinder.

8. The single-cylinder injection device according to claim 5, characterized in that: A waste oil tank is also arranged at the bottom of the front cover of the injection cylinder. The waste oil tank has a cavity for collecting waste oil, and the top of the cavity is open.

9. The single-cylinder injection device according to claim 1, characterized in that: The shooting platform seat is provided with a positioning pin, and the injection cylinder is correspondingly provided with a pin hole; the injection cylinder is fixedly connected to the shooting platform seat through the positioning pin and the fastening screw, so that the injection cylinder drives the shooting platform seat to slide along the second linear guide rail.

10. An injection molding machine, characterized in that: The injection molding machine comprises a single-cylinder injection device as claimed in any one of claims 1 to 9.

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