Testing device for shut-off nozzles

Abstract

This invention provides a test apparatus for shut-off nozzles that does not require an injection molding machine for inspection. [Solution] The test apparatus (1) includes a cylinder (7) into which a test fluid is placed, and a plunger (11) placed inside the cylinder (7) to pressurize the test fluid. The shut-off nozzle (2) to be tested is attached to the cylinder (7). When the test fluid is pressurized by the plunger (11), it is supplied to the shut-off nozzle (2) to be tested. The shut-off nozzle (2) can then be tested.

Description

Technical Field

[0001] The present invention relates to a test apparatus for inspecting whether a shut-off nozzle has the required performance, and a test method for inspecting the quality of a shut-off nozzle.

Background Art

[0002] The shut-off nozzle provided in the injection device of an injection molding machine has a valve structure, and can prevent so-called drooling by opening and closing the flow path through which the injection material of the injection nozzle flows by the valve structure. There are various types of shut-off nozzles. For example, the shut-off nozzle described in Patent Document 1 is configured as follows. That is, this type of shut-off nozzle includes a nozzle portion and a needle valve provided obliquely with respect to this nozzle portion. An oblique hole, that is, a needle hole, which reaches the injection flow path inside the nozzle portion from the outer peripheral surface of the nozzle portion, is formed in the nozzle portion. A needle valve is inserted into this needle hole so as to be able to advance and retreat. When the needle valve is advanced, the injection flow path is closed, and when it is retreated, the injection flow path is opened. That is, the valve structure is composed of the needle valve.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There are various types of shut-off nozzles besides those described above, but all of them are equipped with a valve structure that opens and closes the injection path. When manufacturing shut-off nozzles and shipping them out, it is necessary to test whether they have the required performance. First, it is necessary to test whether the seal by the valve structure is working properly. That is, when the injection path is closed by the valve structure, it is necessary to test whether or not the injection material leaks from the injection port of the shut-off nozzle. Next, in the case of the type of shut-off nozzle described in Patent Document 1, it is necessary to test whether or not the injection material leaks from the needle hole. There is a small gap between the needle hole and the needle valve, which allows the needle valve to move smoothly forward and backward, but if this gap is too large, the injection material will leak out.

[0005] Testing of shut-off nozzles is conducted using a test injection molding machine. Specifically, the shut-off nozzle under test is mounted on the test injection molding machine, and its performance is evaluated by actually performing injection operations. However, conducting these tests requires the preparation of a test injection molding machine, which presents challenges in terms of cost and space requirements.

[0006] This disclosure provides a test apparatus for a shut-off nozzle that does not require an injection molding machine for inspection, and a test method for a shut-off nozzle.

[0007] Other challenges and novel features will become apparent from the description and accompanying drawings in this specification. [Means for solving the problem]

[0008] This disclosure is, The device is configured as a test apparatus for a shut-off nozzle for an injection device, including a nozzle body having an outlet at its tip, and a needle valve that is movably connected to a needle hole provided near the tip of the nozzle body. The test apparatus comprises a housing consisting of side, top, and bottom parts, a support fixed to the inside of the top part of the housing, a cylinder filled with test fluid disposed inside the support, a nozzle mounting member for fixing the nozzle body disposed at the tip of the cylinder, a plunger for pressurizing the test fluid disposed inside the cylinder, and a plunger driving means for driving the plunger disposed on the outside of the top part of the housing. The device is configured so that the test fluid can be supplied to the nozzle body of the shut-off nozzle, and it is possible to check whether or not the test fluid is leaking out of the outlet when the outlet of the nozzle body is closed by the needle valve. [Effects of the Invention]

[0009] This disclosure allows for testing of shut-off nozzles without the use of an injection molding machine for inspection. [Brief explanation of the drawing]

[0010] [Figure 1] This shows a test apparatus for a shut-off nozzle relating to the first embodiment of this implementation, and a front cross-sectional view of the shut-off nozzle. [Figure 2A] This flowchart shows the test method for the shut-off nozzle according to this embodiment. [Figure 2B] This flowchart shows the test method for the shut-off nozzle according to this embodiment. [Figure 3] This shows a test apparatus for a shut-off nozzle relating to the second embodiment of this implementation, and a front cross-sectional view of the shut-off nozzle. [Figure 4A] This is a side cross-sectional view showing a flow resistance element provided in a test apparatus for a shut-off nozzle according to the second embodiment of this implementation. [Figure 4B] This is a front cross-sectional view of the flow resistance element provided in the test apparatus for the shut-off nozzle according to the second embodiment of this implementation, shown as section XX in Figure 4A. [Figure 4C] This is a front cross-sectional view showing a resin supply device provided in a test apparatus for a shut-off nozzle according to the third embodiment of this implementation. [Figure 5] This is a front cross-sectional view showing a part of the test apparatus for the shut-off nozzle according to this embodiment, and a shut-off nozzle equipped with a rotary valve. [Figure 6] This is a front cross-sectional view showing a part of the test apparatus for the shut-off nozzle according to this embodiment, and a shut-off nozzle equipped with a needle valve. [Modes for carrying out the invention]

[0011] The following describes specific embodiments in detail with reference to the drawings. However, the embodiments are not limited to those described below. For clarity, the following descriptions and drawings have been simplified as appropriate. In each drawing, the same elements are denoted by the same reference numerals, and redundant explanations have been omitted where necessary. Also, hatching has been omitted in some parts of the drawings to avoid clutter.

[0012] This embodiment will be described. <First Embodiment> <Test equipment> As shown in Figure 1, the shut-off nozzle test apparatus 1 according to this embodiment is designed to mount the shut-off nozzle 2 to be tested in an upright position, requiring relatively little installation space and being compact in design. As will be explained in more detail later, there are various types of shut-off nozzles 2, and the test apparatus 1 according to this embodiment can test multiple types of shut-off nozzles 2.

[0013] The test apparatus 1 is designed to supply a test fluid to a shut-off nozzle 2 for testing, and its lower portion is covered by a housing 4 to prevent the test fluid from splashing into the surroundings. A pan, or liquid reservoir 6, is provided at the bottom of the housing 4 to receive and collect the test fluid.

[0014] A cylindrical support 5 is fixedly installed inside the housing 4. A cylinder 7 into which the test fluid is placed is placed inside the support 5. A nozzle mounting member 9, fixed by bolts 8, 8, ..., is provided at the tip, i.e., the lower end, of the support 5. The shut-off nozzle 2, which will be described later, is fixed to the support 5 and the cylinder 7 by this nozzle mounting member 9. Once the shut-off nozzle 2 is fixed, its rear end face comes into liquid-tight contact with the lower end face of the cylinder 7. As will be explained later, the test fluid placed in the cylinder 7 will be supplied to the shut-off nozzle 2 without leaking to the outside even when pressurized.

[0015] Such a cylinder 7 is provided with a plunger 11 for pressurizing the test fluid and extruding it. A driving cylinder unit 13 for driving the plunger 11 is provided above the cylinder 7. The driving cylinder unit 13 may be driven by hydraulic pressure, but in this embodiment, it is driven by compressed air from an air supply source 14. Limit switches 15, 15 for detecting the piston 16 are provided in the driving cylinder unit 13, and the position of the plunger 11 is indirectly detected.

[0016] A fluid supply hole 17 reaching the bore of the cylinder 7 from the side surface is formed in the support 5 and the cylinder 7. A plug 18 is attached to the outlet of the fluid supply hole 17. Remove this plug 18 and connect a fluid supply pipe 20 to the fluid supply hole 17 as shown by the dotted line in FIG. 1. Then, when the test fluid is supplied from the funnel 21, the cylinder 7 can be filled with the test fluid. After filling, remove the fluid supply pipe 20 and stop the plug 18. This can prevent the test fluid from spraying out from the fluid supply hole 17 when the test fluid is pressurized by the plunger 11. Note that the fluid supply pipe 20 may be constantly connected to the fluid supply hole 17. In this case, when pressurizing the test fluid by the plunger 11, it is necessary to slowly advance the plunger 11 and pressurize it after the tip of the plunger 11 exceeds the fluid supply hole 17.

[0017] On the housing 4, a bracket 23 is provided on its side, and a piston cylinder unit 24 for driving a needle valve is provided on this bracket 23. The piston cylinder unit 24 for driving the needle valve is adapted to be driven by an air supply source 25 for valve driving. The piston cylinder unit 24 for driving the needle valve may be driven by hydraulic pressure, or may be driven by the air supply source 14 for driving the driving cylinder unit 13 described above. However, in this embodiment, the air supply source 25 for valve driving is separately provided in this way. Corresponding to such a piston cylinder unit 24 for driving the needle valve, an opening 26 is formed in a part of the housing 4.

[0018] <Shut-off nozzle to be tested> The shut-off nozzle 2 to be tested will be described. The shut-off nozzle 2 is composed of a nozzle body 28 and a needle valve 29. In the nozzle body 28, an injection flow path 31 through which an injection material flows is formed along its axis, and the outlet at the tip of the nozzle body 28 is an injection port 32. In the nozzle body 28, a needle hole 33 is obliquely opened in the axial direction from its outer peripheral surface and reaches the injection flow path 31. The needle valve 29 is inserted into this needle hole 33 so as to be able to advance and retreat. That is, in this shut-off nozzle 2 to be tested, the needle valve 29 is provided obliquely with respect to the nozzle body 28. When the needle valve 29 is advanced, the injection flow path 31 is closed. And when it is retracted, the injection flow path 31 is opened. That is, the needle valve 29 has a valve structure for opening and closing the injection flow path of the shut-off nozzle 2.

[0019] The rear end side of such a needle valve 29 protrudes outward from the opening 26 of the housing 4 and is connected to the piston cylinder unit 24 for driving the needle valve. The piston cylinder unit 24 for driving the needle valve serves as a valve driving means for driving the needle valve 29 of the shut-off nozzle 2, that is, the valve structure.

[0020] <Preparation stage for the test> A method for testing the shut-off nozzle 2 using the shut-off nozzle test apparatus 1 according to this embodiment will be described. First, the preparation stage will be described. First, a test fluid is selected. The test fluid is selected from fluids having a viscosity similar to that of molten resin. For example, grease, lubricating oil, or food paste mustard can be selected. Such test fluids can be tested at room temperature, so there is no danger, and since there is no need to heat them with a heater, the test can be performed at a low cost. The selected test fluid is filled into the cylinder 7. That is, as described above, the stopper 18 is removed, and the test fluid is filled into the cylinder 7 using the funnel 21 and fluid supply pipe 20. The fluid supply pipe 20 is removed from the fluid supply hole 17 and the stopper 18 is closed. The preparation stage is completed.

[0021] <Test of sealing effect> The test will determine whether the injection passage 31 can be properly closed by the valve structure. As shown in Figure 2A, the closing process (step S01) is performed. The needle valve driving piston cylinder unit 24 (see Figure 1) is driven to advance the needle valve 29 and close the injection passage 31. Next, the fluid supply process (step S02) is performed. The driving cylinder unit 13 drives the plunger 11 to apply pressure to the test fluid.

[0022] Step S03 is performed to check whether the test fluid leaks from the nozzle 32. This check can be made by an engineer visually, or it can be automated using a camera or similar device. If there is no leakage of the test fluid from the nozzle 32, the sealing action of the needle valve 29 is determined to be normal (Step S04). However, if leakage is detected, the seal is determined to be faulty (Step S05). The sealing action test is then completed.

[0023] <Leakage test from sliding parts> The test will determine whether there is any leakage from the sliding parts in the valve structure of the shut-off nozzle 2. In the shut-off nozzle 2 under test, the needle valve 29 slides against the needle hole 33. Therefore, the test will determine whether there is any leakage from the needle hole 33. The opening process (step S11) is performed as shown in Figure 2B. The needle valve driving piston cylinder unit 24 (see Figure 1) is driven to retract the needle valve 29 and open the injection passage 31. Next, the fluid supply process (step S12) is performed. The driving cylinder unit 13 drives the plunger 11 to inject the test fluid from the injection port 32. The limiter switch 15 stops the driving of the plunger 11 when the plunger 11 reaches the forward position.

[0024] Step S13 is performed to check whether the test fluid is leaking from the needle hole 33. This check can be made by an engineer visually, or it can be automated using a camera or similar device. If there is no leakage of the test fluid from the needle hole 33, it is determined that the gap between the needle valve 29 and the needle hole 33 is within the appropriate range (Step S14). On the other hand, if leakage is detected, it is determined that the gap between the needle valve 29 and the needle hole 33 is too large and abnormal (Step S15). The leak test from the sliding part is then completed.

[0025] <Second Embodiment> The shut-off nozzle test apparatus 1 according to this embodiment can be modified in various ways, and Figure 3 shows the shut-off nozzle test apparatus 1A according to the second embodiment. The same reference numerals are used for the same components and parts as in the test apparatus 1 according to the first embodiment, and their descriptions are omitted.

[0026] <Resin supply device> The test apparatus 1A according to the second embodiment is characterized by the use of molten resin as the test fluid. To use molten resin, the test apparatus 1A is equipped with a resin supply device 35. The resin supply device 35 comprises a heating cylinder 36 and a melting plunger 38 that is slidably mounted within the heating cylinder 36. The heating cylinder 36 is equipped with a hopper 39 and a heater 40 on its outer surface. Therefore, when the heating cylinder 36 is heated by the heater 40 and resin pellets are supplied from the hopper 39 to drive the melting plunger 38, the resin pellets are sent forward while melting.

[0027] <Means for increasing fluid resistance> The resin supply device 35 according to this embodiment is provided with means for efficiently melting the resin, namely means for increasing flow resistance. The means for increasing flow resistance is designed to increase the resistance of the flow path in the heating cylinder 36, and in this embodiment it consists of a flow resistance body 42. The flow resistance body 42 is shown in a side cross-section in Figure 4A and has a plurality of small-diameter through holes 43, 43, .... Furthermore, the front cross-section is shown in Figure 4B and these through holes 43, 43, ... decrease in diameter towards the downstream direction.

[0028] Therefore, when the resin pellets are extruded while being melted by the melting plunger 38 (see Figure 3), the cross-sectional area of ​​the bore of the heating cylinder 36, i.e., the flow path cross-sectional area, decreases in the flow path resistance body 42, and the resin pressure increases. This increase in pressure further raises the temperature of the molten resin. Also, since the flow path resistance body 42 is made of a metal with high thermal conductivity, the resin is heated more efficiently as it passes through the through holes 43, 43, ... Therefore, the resin pellets are melted efficiently.

[0029] A resin supply passage 45 is provided in the support 5 and the cylinder 7 through which molten resin is supplied. The heating cylinder 36 of the resin supply device 35 is coupled to the support 5, and the bore of the heating cylinder 36 is in communication with the resin supply passage 45. Therefore, the molten resin in the resin supply device 35 is supplied into the cylinder 7. In the test apparatus 1A according to this second embodiment, a cylinder heater 47 is provided on the outer surface of the support 5. This ensures that the test fluid, i.e., the molten resin supplied into the cylinder 7 is maintained at an appropriate temperature.

[0030] The test apparatus 1A according to the second embodiment uses molten resin as the test fluid, but the test method is carried out in the same manner as in the first embodiment. Because molten resin is used, the shut-off nozzle 2 can be tested in a more practical manner.

[0031] <Third Embodiment> The test apparatus 1A according to the second embodiment can be further modified. Specifically, the resin supply device 35 can be modified to form the third embodiment. Figure 4C shows the resin supply device 35B provided in the third embodiment. In the resin supply device 35B, the flow resistance increasing means is modified. In this embodiment, the flow resistance increasing means consists of a torpedo-shaped torpedo 49. The torpedo 49 can substantially reduce the cross-sectional area of ​​the flow path, increasing the pressure of the resin and raising the temperature of the molten resin. Furthermore, the resin is efficiently heated and melted when passing through a narrow flow path.

[0032] <Second type of shut-off nozzle> The test apparatus 1 according to this embodiment can test various types of shut-off nozzles 2. Figure 5 shows the test apparatus 1 with a second type of shut-off nozzle 2X attached. The second type of shut-off nozzle 2X consists of a nozzle body 50, a cylindrical rotary valve 51, and a rotating lever 52 for rotating the rotary valve 51. An injection passage 54 is opened in the nozzle body 50, and its tip is the injection port 55. A cylindrical bore 56 is opened in the nozzle body 50 so as to cross the injection passage 54. The rotary valve 51 is placed in this bore 56.

[0033] The rotary valve 51 has a through hole 58 that penetrates it in the diametrical direction. The rotary valve 51 is also provided with a rotating lever 52. The rotating lever 52 is connected to a connecting bar 59, which is connected to a needle valve driving piston cylinder unit 24. Therefore, by driving the needle valve driving piston cylinder unit 24, the rotary valve can be rotated to the first and second rotation positions. Since this needle valve driving piston cylinder unit 24 drives the rotating lever 52, it can also be called a rotating lever driving piston cylinder unit.

[0034] When the rotary valve 51 is rotated to the first rotation position, the injection passage 54 aligns with the through hole 58 and the injection passage 54 opens. On the other hand, when it is rotated to the second rotation position, the injection passage 54 is closed by the land portion of the rotary valve 51. In other words, the rotary valve 51 has a valve structure. In this second type of shut-off nozzle 2X, the sliding point is between the bore 56 and the rotary valve 51. Therefore, a leak test from the sliding point detects whether or not the test fluid is leaking from the bore 56.

[0035] <Third type of shut-off nozzle> Figure 5 shows the test apparatus 1 with a third type of shut-off nozzle 2Y attached. The third type of shut-off nozzle 2Y consists of a nozzle body 61, a needle valve 62, and an operating lever 63 that drives the needle valve 62 in the axial direction. An injection channel 64 is formed in the nozzle body 61, and its tip is the injection port 65. However, the injection channel 64 branches and curves midway, then merges to reach the injection port 65. A support portion 67 is formed in this curved portion.

[0036] The needle valve 62 is mounted coaxially with the injection passage 64, and its tip opens and closes the injection port 65. The rear end of the needle valve 62 is placed in a support portion 67. The end of the operating lever 63 is inserted into this support portion 67 and connected to the rear end of the needle valve 62. The operating lever 63 is connected to the needle valve driving piston cylinder unit 24 via a connecting bar 69. Therefore, when the needle valve driving piston cylinder unit 24 is driven, the needle valve 62 is driven axially, and the injection port 65 is opened and closed. In this third type of shut-off nozzle 2Y, the support portion 67 is a sliding part. Leakage testing of the sliding part detects whether or not there is leakage of the test fluid in this part.

[0037] The present invention has been described in detail above based on embodiments, but it goes without saying that the present invention is not limited to the embodiments already described, and various modifications are possible without departing from the spirit of the invention. The multiple examples described above can also be implemented in combination as appropriate. [Explanation of Symbols]

[0038] 1. Test equipment 2. Shut-off nozzle 4. Enclosure 5. Support 6. Liquid reservoir 7. Cylinder 9 Nozzle mounting component 11 Plunger 13 Drive cylinder unit 14 Air supply source 15 Limiter switch 16 Piston 17 Fluid supply hole 18 Plug 20 Fluid supply pipe 21 Funnel 23 brackets 24 Needle valve drive piston cylinder unit 25 Air supply source for valve drive 26 Opening 28 Nozzle body 29 Needle valve 31 Injection path 32 Injection port 33 Needle hole 35 Resin supply device 36 Heating cylinder 38 Melting plunger 39 hoppers 40 heaters 42 Flow resistance element 43 Through hole 45 Resin supply path 47 Cylinder heater 49 Torpedo 50 Nozzle body 51 Rotary valve 52 Rotating lever 54 Injection path 55 Outlet 56 Bore 58 Through hole 59 Connecting bar 61 Nozzle body 62 Needle valve 63 Operating lever 64 Injection path 65 Injection port 67 Support part 69 Connecting Bar

Claims

1. A nozzle body having an outlet at its tip, The nozzle body includes a needle valve that is movably connected to a needle hole provided near the tip of the nozzle body, A test apparatus for a shut-off nozzle for an injection device, A housing consisting of side sections, a top section, and a bottom section, A support fixed to the inside of the upper surface portion of the housing, A cylinder filled with a test fluid is placed inside the support, A nozzle mounting member for fixing the nozzle body is positioned at the tip of the cylinder, A plunger for pressurizing the test fluid is located inside the cylinder, A plunger driving means for driving the plunger is arranged on the outside of the upper surface portion of the housing, It has, The test fluid can be supplied to the nozzle body of the shut-off nozzle, A test apparatus for a shut-off nozzle that can confirm whether or not the test fluid flows out of the nozzle opening when the nozzle opening of the nozzle body is closed by the needle valve.

2. The shut-off nozzle testing apparatus according to claim 1, further comprising a first opening provided on the side surface of the housing for arranging the needle valve.

3. A test apparatus for a shut-off nozzle according to claim 1, further comprising a fluid supply hole provided so as to penetrate the support and the cylinder for supplying the test fluid.

4. A second opening is provided in a part of the housing, The shut-off nozzle testing apparatus according to claim 3, wherein the test fluid can be filled into the cylinder through the second opening and the fluid supply hole.

5. The plunger driving means includes a piston connected to the plunger, The test apparatus for a shut-off nozzle according to claim 1, wherein the plunger is moved by the piston.

6. The test apparatus for a shut-off nozzle according to claim 5, wherein the piston is driven by compressed air.

7. The test apparatus for a shut-off nozzle according to claim 5, wherein the piston is driven by hydraulic pressure.

8. The test apparatus for a shut-off nozzle according to claim 1, wherein the test fluid is grease, lubricating oil, or mustard paste.

9. The test fluid is a molten resin, The system further includes a resin supply device for melting and supplying resin, A test apparatus for a shut-off nozzle according to claim 1, wherein the molten resin is supplied from the resin supply device to the cylinder via a resin supply passage provided so as to penetrate the support and the cylinder.

10. The test apparatus for a shut-off nozzle according to claim 9, wherein the resin supply device has a heating cylinder for melting the resin.

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