Injection molding probe device

Abstract

By reducing the probe diameter, the degree of freedom in mold design can be increased. This provides an injection molding probe device that can reduce the number of mold parts and assembly man-hours. [Solution] An injection molding probe device 1 comprising a drive rod 3 inserted through a manifold 120, a valve pin 4 whose base end 40 is movable toward and away from the drive rod 3, a spring receiving portion 41 of the valve pin 4, a probe 2 consisting of a runner bush portion 20 and a probe body portion 21, a tip restricting portion 5 provided in the probe 2 or the manifold 120, a base end restricting portion 6 positioned closer to the drive rod 3 than the spring receiving portion 41, a spring housing portion 7 provided between the tip restricting portion 5 and the spring receiving portion 41 that has retracted to the base end restricting portion 6, a compression spring 8 housed in the spring housing portion 7 and biasing the spring receiving portion 41, and a probe internal passage 9 that passes longitudinally through the probe 2, wherein the probe internal passage 9 is arranged parallel to the spring housing portion 7.

Description

Technical Field

[0001] The present invention relates to synthetic resin injection molding technology, and particularly to an injection molding probe device used for hot runner molding.

Background Art

[0002] In a conventional mold for injection molding of thermoplastic resin, a hot runner probe as an injection molding probe device is incorporated. The probe is mounted in a probe mounting hole drilled through a back plate and a cavity plate. A valve pin longitudinally penetrates the probe in a freely advancing and retreating manner, and the proximal end of the valve pin longitudinally penetrates a manifold for a hot runner and is connected to an advancing and retreating drive mechanism provided on a mounting plate to receive an advancing and retreating driving force. The valve pin advances to close the gate of the cavity plate and retreats to open it.

[0003] Since the valve pin longitudinally penetrates the mounting plate, the manifold, the back plate, and the cavity plate, its overall length becomes long. Since the valve pin is processed with a small diameter, a long length, and high precision, it is difficult to extract and mount it during disassembly and assembly of the mold, and it is easily deformed or damaged, and must be handled carefully and delicately, which has been a problem of an increase in work burden and man-hours.

[0004] Also, while the proximal end of the valve pin arranged on the mounting plate is near the atmospheric temperature, the tip reaches the melting temperature of the resin, for example, 200 to 400 °C, so a thermal expansion difference occurs in each part, bending stress acts, malfunction and wear are likely to occur, and the durability life is short. The valve pin has a drawback that it is difficult to obtain machining accuracy and durability strength and becomes expensive as it becomes longer.

[0005] One technique to overcome the drawbacks of the long valve pin is the split valve pin described in Patent Document 1 (Japanese Patent No. 5930741). The split valve pin consists of a reciprocating upper valve pin and a lower valve pin, each formed separately and arranged linearly. The lower end of the upper valve pin, which is inserted into the manifold, is in contact with the head of the lower valve pin, and a coil spring is interposed between the head of the lower valve pin and the flange of the insertion tube, allowing for reciprocating movement via a connecting mechanism. The connecting mechanism consists of upper and lower ring-shaped stoppers that are spaced apart and screw into threaded grooves on the inner circumference of recesses in the valve body, allowing the flange formed on the head of the lower valve pin to slide only between the stoppers. The split valve pin overcomes the drawbacks of its length. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 5930741 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, the probe equipped with a split valve pin as shown in Patent Document 1 has an internal passage within the probe that connects to the manifold runner, which is drilled in a position that is inclined from the outside of the coil spring toward the injection port side of the probe. For this reason, the probe needs to have a larger base diameter, which has the disadvantage of making the probe larger and limiting the freedom of mold design.

[0008] Furthermore, the coil spring that opens the lower valve pin requires different repulsive forces depending on changes in the specifications of the resin molded product and the mold. Therefore, it is necessary to change to a coil spring with the appropriate repulsive force each time the mold or resin material is changed, which has led to an increase in the number of parts in the mold and an increase in assembly man-hours.

[0009] In view of these circumstances, the present invention provides an injection molding probe device that can reduce the diameter of the probe and increase the degree of freedom in mold design. Furthermore, the present invention provides an injection molding probe device that can adjust the repulsive force of the valve pin's compression spring in accordance with changes in the mold or resin material, thereby reducing the number of mold parts and assembly man-hours. [Means for solving the problem]

[0010] The present invention comprises a drive rod whose tip is inserted into a manifold and which moves back and forth; a valve pin whose base end, inserted into the manifold, faces the tip of the drive rod so as to be able to move toward and away from it, and which is arranged in the same line as the drive rod; a spring receiving portion provided near the base end of the valve pin; a probe consisting of a runner bush portion and a probe body portion, through which the valve pin can move back and forth; a tip restricting portion provided in the probe or the manifold; and a portion positioned closer to the drive rod than the spring receiving portion. The present invention provides an injection molding probe device comprising: a base end restricting portion that restricts the retracted position of the spring receiving portion; a spring housing portion provided between the tip restricting portion and the spring receiving portion retracted to the base end restricting portion; a compression spring housed in the spring housing portion that biases the spring receiving portion and the valve pin toward the base end restricting portion; and an internal probe flow path that passes longitudinally through the runner bush portion and the probe body portion, wherein the internal probe flow path has a range corresponding to the spring housing portion that is arranged parallel to the spring housing portion.

[0011] According to the injection molding probe device, the valve pin can be shortened, and the valve pin can be produced at a lower cost and with higher precision. Since the entire or main range of the spring housing is located within the manifold, the probe can be made smaller. Furthermore, since the internal flow path of the probe is arranged parallel to the spring housing in the range corresponding to the spring housing, the diameter of the probe body can be made smaller compared to conventional types in which the range corresponding to the spring housing is also arranged at an angle. This reduction in the diameter of the probe body further increases the degree of freedom in mold design.

[0012] Since the injection molding probe device has the range of the internal flow path of the probe corresponding to the spring housing parallel to the spring housing, even when the base end of the spring housing is located inside the manifold and the tip end of the spring housing is located inside the runner bush, or when the base end of the spring housing is located inside the manifold and the tip end of the spring housing is located on the base end side of the probe body, the probe body can be made even smaller and smaller in diameter than the conventional type.

[0013] The reciprocating rod moves in the direction that closes the valve pin and retracts in the direction that opens it. The reciprocating rod exerts sufficient driving force to close the valve pin against the repulsive force of the compression spring. The reciprocating rod is inserted into the manifold so as to be able to move back and forth, and the tip of the reciprocating rod faces the base end of the valve pin so as to be able to press against the base end of the valve pin. The reciprocating rod can be provided on the mounting plate together with a reciprocating drive mechanism that drives the reciprocating rod back and forth. The reciprocating drive mechanism operates, for example, under control from the control unit of an injection molding machine, and is driven to move back and forth by fluid pressure such as pneumatic or hydraulic pressure. The reciprocating drive mechanism has, for example, a cylinder and a piston that reciprocates within the cylinder with a drive source, and the piston drives the reciprocating rod back and forth.

[0014] The manifold allows the tip of the reciprocating rod and the base end of the valve pin to be inserted and moved back and forth. The manifold includes, for example, a guide bush for the reciprocating rod and a spring housing. Furthermore, the manifold may be provided with a tip restrictor and a base restrictor. The manifold has a sprue bush and a runner, and maintains the runner, from the sprue bush to the probe, at the melting temperature of the resin. A manifold heater may be provided around the runner of the manifold. The manifold heater is controlled, for example, from the injection molding control unit and generates heat using external power.

[0015] The probe has the valve pin and the internal passage through it. The valve pin retracts to open the gate of the cavity plate and advances to close it. The valve pin retracts in response to the repulsive force of the compression spring and advances in response to the pressing force of the reciprocating rod against the compression spring. When the gate is open, the internal passage of the probe fills the cavity with molten resin, and when the gate is closed, it stops filling the cavity with molten resin.

[0016] The probe consists of a runner bush and a probe body. The runner bush can be fixed to a back plate, for example, and the probe body can be mounted on a cavity plate. The probe body has an injection port at its tip that leads to the internal flow path of the probe, and the injection port is positioned at the gate of the cavity plate. The peripheral wall of the probe body has a probe heater, which heats the probe to the melting temperature of the resin. The probe heater is controlled, for example, from the injection molding control unit and generates heat using external power.

[0017] The valve pin opens the nozzle by receiving the repulsive force of the compression spring, and closes the nozzle by receiving a pressing force from the reciprocating rod that opposes the compression spring. When the nozzle is opened, the reciprocating rod retracts in response to the driving force of the reciprocating drive mechanism, and the valve pin, receiving the repulsive force of the compression spring, follows the reciprocating rod and retracts to a position restricted by the base end restricting portion. The valve pin has a spring receiving portion near its base end that abuts against the compression spring, a middle portion that passes longitudinally through the inside of the compression spring housed in the spring housing portion, and a tip that becomes a tip valve that opens and closes the nozzle.

[0018] The tip restricting portion restricts the tip position of the compression spring. The tip restricting portion sets a spring housing portion between the spring receiving portion, which is retracted to the base restricting portion. The tip restricting portion can be located in the manifold, runner bush portion, or probe body portion.

[0019] The base end restricting portion restricts the retracted position of the spring receiving portion. The base end restricting portion sets a spring housing portion between the spring receiving portion, whose retracted position is restricted by the base end restricting portion, and the tip restricting portion. The base end restricting portion can be arranged within the manifold.

[0020] The spring housing accommodates the compression spring between the tip restricting portion and the spring receiving portion that retracts to the base restricting portion. The middle portion of the valve pin that passes through the compression spring runs longitudinally through the spring housing. The spring housing can be set to an inner diameter slightly exceeding the outer diameter of the compression spring, to accommodate the compression spring so that it can expand and contract, and to a length that restricts the compression spring to a partially expanded state with pre-compression applied.

[0021] The compression spring biases the valve pin with a repulsive force in the opening direction. The compression spring has a free-extended length that is longer than the length of the spring housing and is housed in the spring housing in a partially extended state with pre-compression applied. The compression spring biases the spring receiving portion of the valve pin with sufficient effective driving force to retract the valve pin, which is exposed to molten resin and subjected to resistance due to its viscosity.

[0022] The compression spring can be made of a material, shaped, and have external dimensions that allow it to exert sufficient repulsive force (effective driving force) to retract the valve pin, whose tip is in contact with the molten resin. The compression spring receives a compressive force from the drive rod in an effective extended length range where it can exert an effective repulsive force (effective driving force) of 10 to 30 kgf, starting from the partially extended state after receiving the pre-compression. When the compressive force from the drive rod 3 is released, the compression spring returns to the partially extended state after receiving the pre-compression by exerting the effective repulsive force (effective driving force). The effective driving force can be, for example, 5 to 40 kgf. The compression spring can be, for example, a coil spring with a total length of 35 to 55 mm and an outer diameter of 5 to 14 mm, and its spring constant can be 0.2 to 1.8 kgf / mm.

[0023] The internal flow path of the probe supplies molten resin from the runner bush portion of the probe to the ejection port at the tip of the probe body portion. The internal flow path of the probe penetrates through the runner bush portion and the probe body portion, and is arranged in parallel with the spring housing portion within the range corresponding to the spring housing portion. The internal flow path of the probe is arranged parallel or concentric with the valve pin in the range where the spring housing portion of the probe body portion is not provided, and the diameter of the probe body portion can be set to be smaller.

[0024] The repulsive force adjusting mechanism adjusts the repulsive force of the compression spring within the range of the effective repulsive force (effective driving force) of the compression spring. The repulsive force adjusting mechanism can be provided at at least one of the tip regulating portion, the base end regulating portion, and the spring receiving portion. The repulsive force adjusting mechanism can change the internal length of the spring housing portion and adjust the maximum expansion length of the compression spring. The repulsive force adjusting mechanism adjusts the length of the spring housing portion so that the compression spring falls within the intermediate expansion range where it can exert an effective repulsive force (effective driving force). The repulsive force adjusting mechanism, for example, moves at least one of the tip regulating portion, the base end regulating portion, and the spring receiving portion in the advancing and retreating direction of the valve pin, has a temporary fixing function portion at the regulating position, and can adjust and temporarily fix the length of the spring housing portion.

[0025] The repulsive force adjusting mechanism can be formed by the runner bush portion integrated with the tip regulating portion. The runner bush portion can be a part integrated with or separate from the probe body portion. The tip regulating portion is formed by a plurality of runner bush portions having different thickness dimensions in the advancing and retreating direction of the valve pin, or a plurality of probes, and the length of the spring housing portion can be adjusted by replacing the parts with respect to the back plate or the cavity plate.

[0026] The repulsive force adjustment mechanism can be formed by a spacer mounted between the tip restricting portion and the tip of the compression spring. The repulsive force adjustment mechanism can be formed by a spacer mounted between the base end restricting portion and the base end of the spring receiving portion. Also, the repulsive force adjustment mechanism can be formed by a spacer mounted between the tip of the spring receiving portion and the base end of the compression spring. The spacer is prepared with a plurality of spacers having different thicknesses in the advancing and retreating directions of the valve pin, and by replacing the spacers with different dimensions, the length of the spring housing portion can be adjusted. The spacer is formed in an annular or C-shaped form that fits slidably over the valve pin, and its outer peripheral edge abuts against the inner wall of the spring housing portion, and it can also serve as a support and guide function for guiding the valve pin to advance and retreat without axial movement.

[0027] The repulsive force adjustment mechanism has a support portion and an advancing / retreating portion that advances and retreats with respect to the support portion and can be temporarily fixed. The dimension between the support portion and the advancing / retreating portion is made variable, and the length of the spring housing portion can be adjusted without replacing parts. The repulsive force adjustment mechanism is provided with a support portion having either a male or female screw, and an advancing / retreating portion having either a male or female screw and screwed on via a fastening nut that forms a double nut with respect to the screw of the support portion, and the adjusted dimension between the support portion and the advancing / retreating portion can be more reliably temporarily fixed.

[0028] The present invention can be an injection molding probe device in which the tip restricting portion is provided at the base end of the runner bush portion. According to the above means, since the spring housing portion can be incorporated within the range of the manifold from the base end of the runner bush portion, the entire probe can be reduced in diameter.

[0029] The present invention can be an injection molding probe device provided with a repulsive force adjustment mechanism for adjusting the length of the spring housing portion in the expansion and contraction direction of the compression spring at at least one of the tip restricting portion, the base end restricting portion, and the spring receiving portion.

[0030] According to the above means, one type of compression spring can be widely used, and the number of types of compression springs required for the entire mold can be significantly reduced. The rebound force adjustment mechanism can be assembled by preparing multiple spacers of different dimensions and selecting a spacer. The rebound force adjustment mechanism has a dimension change function and can be assembled with changed dimensions.

[0031] The present invention comprises a drive rod that passes longitudinally through the manifold, with its tip inserted into the runner bush portion or probe body portion of the probe, and drives it to move back and forth; a valve pin whose base end, inserted into the runner bush portion or probe body portion, is positioned opposite the tip of the drive rod so as to be able to move toward and away from it, and which is aligned in the same line as the drive rod and passes longitudinally through the probe body portion so as to be able to move back and forth; a spring receiving portion provided near the base end of the valve pin; a tip restricting portion provided on the tip side of the spring receiving portion within the probe body portion; and the runner The present invention provides an injection molding probe device comprising: a base end restricting portion disposed in the bush portion and restricting the retracted position of the spring receiving portion; a spring housing portion provided between the tip restricting portion and the spring receiving portion retracted to the base end restricting portion; a compression spring housed in the spring housing portion and biasing the spring receiving portion and the valve pin toward the base end restricting portion; and an internal probe flow path that runs longitudinally through the runner bush portion and the probe body portion, wherein the internal probe flow path has a range corresponding to the spring housing portion that is arranged parallel to the spring housing portion.

[0032] According to the above means, even when the spring housing is built into the probe, the diameter of the probe can be reduced. Since the internal flow path of the probe is arranged parallel to the spring housing, a more compact structure can be achieved compared to a conventional arrangement in which the internal flow path of the probe is inclined with respect to the spring housing.

[0033] The tip restrictor can be provided within the probe body, and the base restrictor can be provided in the runner bush. The runner bush is a separate component from the probe body, and the two can be combined to form a single probe, with the spring housing being formed between the runner bush and the probe body.

[0034] The present invention provides an injection molding probe device in which, when the entire spring housing is incorporated into the probe, a repulsion force adjustment mechanism is provided at least one of the tip restrictor, the base restrictor, and the spring receiving portion, which allows adjustment of the length of the spring housing in the expansion and contraction direction of the compression spring.

[0035] According to the above means, even when the spring housing is built into the probe, the number of types of compression springs required for the mold can be significantly reduced. The rebound force adjustment mechanism can be provided, as described above, with a tip restricting portion, a base restricting portion, or a retraction restricting portion that limits the amount of retraction of the spring receiving portion when the compression spring is fully extended within the spring housing, and a temporary fixing mechanism for temporarily fixing the position of the retraction restricting portion, so as to change the length of the spring housing. The rebound force adjustment mechanism can be provided, as described above, with a plurality of spacers of different thicknesses that can be replaced according to the conditions. [Effects of the Invention]

[0036] The present invention provides an injection molding probe device that allows for a smaller probe diameter and greater freedom in mold design. Furthermore, it provides an injection molding probe device that allows for adjustment of the rebound force of the valve pin's compression spring in response to changes in the mold or resin material, thereby reducing the number of mold parts and assembly man-hours. [Brief explanation of the drawing]

[0037] [Figure 1] Cross-sectional view of injection molding probe device 1 (a) Cross-sectional view of injection molding probe device 1 with gate 142 closed (b) Cross-sectional view of injection molding probe device 1 with gate 142 open (c) Front view of drive rod 3 and valve pin 4 [Figure 2]Cross-sectional view of injection molding probe device 1 (a) Cross-sectional view showing spacer 84 as repulsion force adjustment mechanism 84 (b-1) Cross-sectional view of repulsion force adjustment mechanism 84 provided on guide bush 121 (b-2) Cross-sectional view of repulsion force adjustment mechanism 84 with different protrusion dimensions 60 (c) Cross-sectional view of spring housing 7 provided inside manifold 120 from near the base end of runner bush portion 20 [Figure 3] (a) Cross-sectional view of the injection molding probe device 1. Cross-sectional view of the spring housing 7 located inside the manifold 120, near the base end of the probe body 21. (b) Three-view drawing showing another form of the repulsion force adjustment mechanism 84. [Figure 4] Graph showing the relationship between the unfolded length of the compression spring 7 and the rebound force (range of effective rebound force). [Modes for carrying out the invention]

[0038] Hereinafter, with reference to the drawings, the injection molding probe device according to this embodiment will be described in detail. In particular, this embodiment includes a drive rod 3 that is inserted into the manifold 120 at its tip 30 and driven to move back and forth, a valve pin 4 whose base end 40, inserted into the manifold 120, is positioned opposite the tip 30 of the drive rod 3 so as to be able to move toward and away from it and is arranged in the same straight line as the drive rod 3, a spring receiving portion 41 provided near the base end 40 of the valve pin 4, a runner bush portion 20 and a probe body portion 21, through which the valve pin 4 is able to move back and forth, a tip restricting portion 5 provided in the probe 2 or the manifold 120, and the drive The probe device 1 for injection molding has a base end restricting portion 6 positioned on the rod 3 side to restrict the retracted position of the spring receiving portion 41, a spring housing portion 7 provided between the tip restricting portion 5 and the spring receiving portion 41 that has retracted to the base end restricting portion 6, a compression spring 8 housed in the spring housing portion 7 that biases the spring receiving portion 41 and the valve pin 4 toward the base end restricting portion 6, and a probe internal flow path 9 that passes longitudinally through the runner bush portion 20 and the probe body portion 21, wherein the probe internal flow path 9 is arranged parallel to the spring housing portion 7 in the range corresponding to the spring housing portion 7.

[0039] As shown in Figures 1(a) to 1(c), the mold 100 on which the injection molding probe device 1 is mounted has a mounting plate 110, a manifold 120, a back plate 130, and a cavity plate 140. A drive rod 3 is housed in the mounting plate 110 so as to be able to move back and forth, and a reciprocating drive mechanism (not shown) is connected to the base end 32 of the drive rod 3. The middle portion 31 of the drive rod 3 is inserted into a sleeve 111 that extends from inside the mounting plate 110 to a guide bush 121 mounted on the base end of the manifold 120. The tip of the drive rod 3 reaches inside the guide bush 121 (inside the manifold 120).

[0040] The guide bush 121 is attached to the manifold 120 by a plurality of fixing bolts 123 parallel to the forward and backward direction of the drive rod 3. The guide bush 121 has a guide hole 122 with an inner diameter sufficiently larger than the outer diameter of the middle section 31 of the drive rod 3. The cylindrical tip of the guide bush 121, which forms the tip of the guide hole 122, becomes the base end restricting section 6. As shown in Figure 1(c), the tip 30 (contact surface 300) of the drive rod 3 has a shear-free joining mechanism 30, which has an outer diameter set to slidably contact the inner wall of the guide hole 122, and moreover, the tip 30 has a concave cross-sectional shape into which the base end 40 (contact surface 400) of the valve pin 4 can be fitted slidably and moved toward and away from in the shear direction. As shown in Figures 1(a) to 1(c), the contact surface 400 of the valve pin 4 can be provided at the base end 40 of the valve pin 4, which protrudes further towards the base end than the spring receiving portion 41, or, as shown in Figures 2(a), 2(c), etc., it can be provided at the base end of the spring receiving portion 41.

[0041] As shown in Figure 1(a), the valve pin 4 has its base end 40 positioned inside the manifold 120, and its tip penetrates the probe 2 mounted on the back plate 130 and cavity plate 140. The tip of the probe 2 has an injection port 22 facing the gate 142 of the cavity plate 140 (cavity 141). The probe 2 has the runner bush portion 20 and the probe body portion 21 integrated together, and has a probe heater 23 around its outer circumference. The base end of the runner bush portion 20 protrudes from the base end of the back plate 130 toward the manifold 120 and is joined to the tip of the manifold 120, forming the tip restricting portion 5.

[0042] The valve pin 4 has a spring receiving portion 41 near its base end 40, and the base end 40 is fitted to the shear-free joint mechanism 30 of the drive rod 3 so as to be slidable and movable toward and toward the shear direction. The manifold 120 has a columnar spring housing portion 7 between the spring receiving portion 41 that abuts against the base end restricting portion 6 (the tip of the guide bush 121) and the tip restricting portion 5 (the base end of the runner bush portion 20).

[0043] The surrounding wall of the spring receiving portion 41 is in slidable contact with the inner circumferential wall of the spring housing portion 7. A compression spring 8, made of a coil spring, is housed in the spring housing portion 7 in a partially unfolded state with pre-compression applied. As shown in Figure 1(b), when the driving force of the drive rod 3 is removed, the compression spring 8 biases the spring receiving portion 41 and the valve pin 4 until they reach the base end restricting portion 6, opening the gate 142. When the compression spring 8 receives the driving force of the drive rod 3, it compresses until the valve pin 4 closes the gate 142.

[0044] The manifold 120 has a sprue bush (not shown) and a runner 124 connected thereto. The downstream end of the runner 124 is adjacent to the tip of the spring housing 7 and is positioned in a range corresponding to the base end of the runner bush 20, and is connected to the base end of the probe internal passage 9 that runs longitudinally through the probe 2. The base end of the probe internal passage 9 is adjacent to the valve pin 4 that runs longitudinally through the center of the probe 2, and within the range of the runner bush 20, it is inclined toward the valve pin 4, and within the probe body 21, it is positioned concentrically with the valve pin 4 and reaches the injection port 22. As shown in Figure 1(a), since the spring housing 7 is provided inside the manifold 120, the outer diameter dimension 200 of the runner bush 20 can be made smaller compared to the conventional type.

[0045] As shown in Figure 2(c), even in an injection molding probe device 1 in which the spring housing portion 7 is located within the manifold 120 and within a range corresponding to the base end of the runner bush portion 20, the diameter of the probe 2 can be reduced because the internal passage 9 of the probe in the range 90 corresponding to the spring housing portion 7 is arranged parallel to the spring housing portion 7. The spring receiving portion 41 can be provided at the base end 40 of the valve pin 4. The spring receiving portion 41 can contact the tip 30 (shearless joint mechanism 30) of the drive rod 3 in a manner that allows for easy movement toward and away from it.

[0046] As shown in Figure 2(c), the shear-free joint mechanism 30 is configured such that a V-shaped recessed portion engraved on the tip 30 of the drive rod 3 and a V-shaped convex portion protruding from the spring receiving portion 41 of the base end 40 of the valve pin 4 are slidably engaged and move toward and away from each other in a direction perpendicular to the forward / backward direction (axis) (shear direction). The shear-free joint mechanism 30 can release the shear force generated between the two due to temperature differences, etc. The shear-free joint mechanism 30 can be installed on the base end 40 of the valve pin 4, or on the spring receiving portion 41 provided on the base end 40 of the valve pin 4. The shear-free joint mechanism 30 can be installed between the tip 30 of the drive rod 3 and the base end 40 of the valve pin 4, or on the spring receiving portion 41 provided on the base end 40 of the valve pin 4.

[0047] In the injection molding probe device 1 shown in Figure 3(a), the spring housing 7 is housed within the area from the tip side of the manifold 120 to the runner bush 20 and near the base end of the probe body 21. In the injection molding probe device 1 shown in Figure 3(b), the spring housing 7 is housed within the probe body 21 from near the tip of the runner bush 20. In either case, the internal probe flow path 9 in the area 90 corresponding to the spring housing 7 is arranged parallel to the spring housing 7, thereby reducing the diameter of the probe 2.

[0048] The injection molding probe device 1 shown in Figure 3(a) incorporates a tip nozzle 210 as a separate component at the tip of the probe body 21. This makes it easier to route the power harness of the nozzle heater 211 to the outside of the probe body 21, and also reduces the maintenance time required for the tip nozzle 210 and the nozzle heater 211.

[0049] As shown in the graphs of Figures 1(a) and 4, the compression spring 8 has, for example, a free-extended length 80 of 45-50 mm. When housed in the spring housing 7, it is subjected to a pre-compression of about 10 kg, compressing it by approximately 20 mm of the pre-compression dimension g81, resulting in a partially extended state with a pre-compression length 82 of 25-30 mm. The compression spring 8 receives the compressive force from the drive rod 3 within a range of 7-10 mm of the effective extended length range 83, which can exert an effective repulsive force (effective driving force) of 10-30 kgf. When the drive rod 3 retracts and the compressive force is released, the compression spring 8 follows the retraction of the drive rod 3 and returns to its original pre-compression length 82 of 25-30 mm, bringing the spring receiving portion 41 into contact with the base end restricting portion 6.

[0050] As shown in Figures 1(a), (b) and 2(b-1), (b-2), the rebound force adjustment mechanism 84 prepares multiple guide bushes 121 with different thickness dimensions 1210 within the manifold 120 of the flange portion, or protrusion dimensions 60 of the tip 6 which becomes the base end restricting portion 6, and by replacing the guide bush 121, the position of the base end restricting portion 6 can be adjusted in the direction of expansion and contraction of the compression spring 8. The rebound force adjustment mechanism 84 can adjust the compression spring 8 housed in the spring housing portion 7 to the pre-compression length 82 shown in Figure 4.

[0051] As shown in Figure 1(c), the rebound force adjustment mechanism 84 can be a spacer 84 made up of a plurality of annular flat plates of different thicknesses. The spacer 84 can be installed between the tip restricting portion 5 and the tip of the compression spring 8. The spacer 84 can be installed between the base end of the compression spring 8 and the spring receiving portion 41. The spacer 84 installed between the base end of the compression spring 8 and the spring receiving portion 41 performs the function of the spring receiving portion 41 of the valve pin 4.

[0052] As shown in Figure 2(a), the spacer 84 installed between the base end of the compression spring 8 and the spring receiving portion 41 has its outer diameter and outer circumference set to dimensions and shape that allow it to slide freely against the inner wall of the spring housing portion 7, and can also serve the function of guiding the valve pin 4 in the forward and backward directions. By preparing multiple spacers 84 with different diameters, the outer diameter of the spring receiving portion 41 can be adjusted to match various inner diameters of the spring housing portion 7. The spring receiving portion 41 can be provided at the base end 40 of the valve pin 4. In this case, the spring receiving portion 41 is joined to the tip 30 (shearless joint mechanism 30) of the drive rod 3 so as to be able to move toward and away from it.

[0053] The rebound force adjustment mechanism 84 can have the shape shown in Figure 3(b). The probe 2 to which the rebound force adjustment mechanism 84 is attached has a probe body portion 21 and a runner bush portion 20 integrated together, and a rectangular concave mounting groove 201 is recessed at the base end of the runner bush portion 20 in the diametrical direction that does not interfere with the internal flow path 9 of the probe. Screw holes are provided at two locations on the outer diameter side of the center of the mounting groove 201 that corresponds to the spring housing portion 7.

[0054] The rebound force adjustment mechanism 84 has a rectangular parallelepiped shape that fits into the mounting groove 201, and a base portion 840 with screw mounting holes corresponding to the two screw holes, and a base end restricting portion 6 projecting from the center of the base portion 840 for attachment to the spring housing portion 7. The base end restricting portion 6 is pipe-shaped with a guide hole in the center that guides the tip 30 of the drive rod 3 and the base end 40 of the valve pin 4 to move back and forth. The rebound force adjustment mechanism 84 can be attached to the runner bush portion 20 by screw 841. Multiple rebound force adjustment mechanisms 84 with different protrusion dimensions 60 of the base end restricting portion 6 can be prepared and the rebound force of the compression spring 8 can be adjusted by replacing them.

[0055] Since the probe 2 integrates the valve pin 4 and the repulsion force adjustment mechanism 84, it is easy to attach to the back plate 130 and cavity plate 140, and the probe 2 can also be handled independently. [Industrial applicability]

[0056] The injection molding probe device of the present invention can be used in technical fields such as the manufacturing and assembly of molding dies and mold parts, the manufacturing of molded products using the dies, and the maintenance, inspection, and management of the dies. [Explanation of Symbols]

[0057] 1. Probe device for injection molding 2 probes 20 Runner bush section 200 Outer diameter dimensions of the runner bush section 20 201 Same mounting groove 21 The same probe body 210 Same tip nozzle 211 Nozzle heater 22 Same injection port 23. Probe heater 3 Drive Rod 30 Same tip 300 Same contact surface (shearless joining mechanism) 31 Same middle part 32 Proximal end 4 valve pins 40 Proximal end 400 Same contact surface 41 Same Spring receiving part 5 Advanced Regulatory Section 6. Base end regulating section 60 The protruding dimension of the tip 6 of the guide bush 121. 7. Spring housing 8 Compression spring 80 Same Free Expansion Length 81 Same Pre-compression dimensions 82 Same Pre-compression length 83 Same effective deployment range 84. Same rebound force adjustment mechanism (spacer) 840 Same base section 841 Same screw 9. Probe internal flow path 90 Same as the range corresponding to the spring housing 7 100 molds 110 Mounting plate 111 Same sleeve 120 Same Manifold 121 Same Guide Bush 1210 Thickness dimension of the flange portion of the guide bush 121 122 Same guide hole 123 Same fixing bolt 124 Same runner 130 Same backplate 140 Same Cavity Plate 141 Same Cavity 142 Same gate

Claims

1. A drive rod that is inserted through the manifold and moves back and forth, A valve pin is positioned so as to be able to move toward and away from the tip of the drive rod, with its base end inserted through the manifold facing the tip of the drive rod, and is aligned in the same line as the drive rod. A spring receiving portion provided near the base end of the valve pin, The probe consists of a runner bush and a probe body, with the valve pin passing through it so as to be able to move back and forth. The tip restricting portion provided within the probe or the manifold, A base end restricting portion is positioned on the drive rod side of the spring receiving portion and restricts the retracted position of the spring receiving portion, A spring housing is provided between the aforementioned tip restricting portion and the spring receiving portion that has retracted to the aforementioned base restricting portion, A compression spring housed in the spring housing and biasing the spring receiving portion and the valve pin toward the base end restricting portion, The runner bush portion and the probe body portion have internal probe channels that pass through them longitudinally. It has, The probe device for injection molding has a channel within the probe that corresponds to the spring housing and is arranged parallel to the spring housing.

2. The injection molding probe device according to claim 1, wherein the tip restricting portion is provided at the base end of the runner bush portion.

3. The injection molding probe device according to claim 1, wherein a repulsive force adjustment mechanism is provided at least one of the tip restricting portion, the base restricting portion, and the spring receiving portion, which allows adjustment of the length of the spring housing portion in the expansion and contraction direction of the compression spring.

4. A drive rod that runs longitudinally through the manifold, with its tip inserted into the runner bush or probe body of the probe, and drives it to move back and forth, A valve pin is positioned in the same line as the drive rod, with its base end, inserted through the runner bush or the probe body, facing the tip of the drive rod so as to be able to move toward and away from it, and extending longitudinally through the probe body so as to be able to move forward and backward, A spring receiving portion provided near the base end of the valve pin, A tip restricting portion is provided on the tip side of the spring receiving portion within the probe body, The runner bush portion is provided with a base end restricting portion that restricts the retracted position of the spring receiving portion, A spring housing is provided between the aforementioned tip restricting portion and the spring receiving portion that has retracted to the aforementioned base restricting portion, A compression spring housed in the spring housing and biasing the spring receiving portion and the valve pin toward the base end restricting portion, The runner bush portion and the probe body portion have internal probe channels that pass through them longitudinally. It has, The probe device for injection molding has a channel within the probe that corresponds to the spring housing and is arranged parallel to the spring housing.

5. The injection molding probe device according to claim 4, wherein a repulsive force adjustment mechanism is provided at least one of the tip restricting portion, the base restricting portion, and the spring receiving portion, which allows adjustment of the length of the spring housing portion in the expansion and contraction direction of the compression spring.

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