Forming device

Abstract

The present invention provides a molding apparatus capable of generating greater force to maintain the meshed state of the clamping split nut using a mold clamping device. [Solution] The molding apparatus 100 includes a tie bar 10 provided with a clamping groove 10a, a movable die plate 12, a pair of clamping split nuts that restrict the movement of the movable die plate 12 relative to the tie bar 10 by engaging with the clamping groove 10a, a split nut drive unit 3 for moving the clamping split nuts 4, and a toggle mechanism 5 having a plurality of link members 50 that transmit the force of the split nut drive unit 3 to the clamping split nuts 4, and a clamping device 103 provided on the movable die plate 12, wherein the toggle mechanism 5 is configured to lock the plurality of link members 50 so that the relative positions of the plurality of link members 50 are maintained against the force that tries to release the engagement of the clamping split nuts 4 when the clamping split nuts 4 are engaged with the clamping groove 10a.

Description

Technical Field

[0001] The present invention relates to a molding apparatus provided with a split nut for mold clamping.

Background Art

[0002] Conventionally, a molding apparatus provided with a split nut for mold clamping is known (for example, refer to Patent Document 1).

[0003] The above Patent Document 1 discloses a molding apparatus provided with a mold clamping device having a pair of half nuts and a cylinder for driving the pair of half nuts. The pair of half nuts are disposed on a movable die plate, and restrict movement of the movable die plate relative to the tie bars by meshing with groove portions of the tie bars.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0005] However, in the mold clamping device of the above Patent Document 1, the meshed state of the half nuts with the groove portions of the tie bars is maintained by the cylinder that drives the half nuts. For this reason, during injection of the molding material into the mold, there are restrictions on the injection pressure of the molding material into the mold, and the shape, size, etc. of the molded product, so that an excessive mold opening force exceeding the holding force of the cylinder is not generated and the half nuts do not open. Therefore, conventionally, it has been desired to generate a larger force by the mold clamping device to maintain the meshed state of the half nuts, so that the half nuts do not open during injection of the molding material into the mold.

[0006] This invention was made to solve the above-mentioned problems, and one of its objectives is to provide a molding apparatus that can generate a greater force to maintain the meshing state of the clamping split nut by the clamping device. [Means for solving the problem]

[0007] To achieve the above objective, a molding apparatus in one aspect of the present invention includes a tie bar provided with a clamping groove, a movable die plate that moves along the tie bar while holding a movable mold, a pair of clamping split nuts that restrict the movement of the movable die plate relative to the tie bar by engaging with the clamping groove when the mold is closed, a split nut drive unit for moving the clamping split nuts, and a toggle mechanism having a plurality of link members that transmit the force of the split nut drive unit to the clamping split nuts, wherein the toggle mechanism is configured to lock the plurality of link members so that, when the clamping split nuts are engaged with the clamping groove, the relative positions of the plurality of link members are maintained against a force that would cause the clamping split nuts to open and release the engagement.

[0008] In a molding apparatus according to one aspect of this invention, as described above, a clamping device is provided that includes a pair of clamping split nuts, a split nut drive unit, and a toggle mechanism having a plurality of link members that transmit the force of the split nut drive unit to the clamping split nuts. The toggle mechanism locks the plurality of link members so that when the clamping split nuts are engaged with the clamping grooves, the relative positions of the plurality of link members are maintained against the force that tries to open the clamping split nuts and release the engagement. As a result, when a force is generated that tries to open the clamping split nuts and release the engagement during injection of molding material into the mold, the engaged state of the clamping split nuts can be maintained by the force of the locked plurality of link members of the toggle mechanism, rather than by the force of the split nut drive unit. Therefore, compared to conventional clamping devices that maintain the engagement state by a cylinder that drives a half nut, the clamping device can generate a greater force to maintain the engaged state of the clamping split nuts.

[0009] In the molding apparatus according to the first aspect described above, preferably, the toggle mechanism is configured to lock multiple link members by arranging multiple link members linearly in a meshed state. With this configuration, multiple link members can be easily locked by arranging multiple link members linearly.

[0010] In the molding apparatus according to the first aspect described above, preferably, one clamping device is provided on one of the pair of clamping split nuts and one on the other, and the toggle mechanism of each clamping device is configured to lock multiple link members. With this configuration, when multiple clamping split nuts are driven by one split nut drive unit as in the conventional method, a structure such as gears is required to transmit the driving force from one split nut drive unit to multiple clamping split nuts. However, when only the clamping split nuts are driven by one split nut drive unit, the above-mentioned structure such as gears is unnecessary. Therefore, the configuration of the device for transmitting the driving force can be simplified.

[0011] In the molding apparatus according to the first aspect described above, preferably, the split nut drive unit has an electric drive source, and is configured to turn off the electric drive source so that no force is applied from the electric drive source to the toggle mechanism when multiple link members are locked by the toggle mechanism. With this configuration, the electric drive source can be turned off when multiple link members are locked by the toggle mechanism, thereby reducing the power consumption of the clamping device.

[0012] In the configuration in which the toggle mechanism described above arranges a plurality of link members in a straight line when engaged, preferably, the plurality of link members include a first link member connected to a clamping split nut and a second link member connecting the first link member to the split nut drive unit. The first and second link members are configured to be switched by the split nut drive unit from a non-engaged state in which the connection position of the first and second link members is bent in a V-shape when the engagement between the clamping split nut and the clamping groove is released, to an engaged state in which the first and second link members are arranged in a straight line. With this configuration, the plurality of link members can be locked more easily by switching from a state in which the first and second link members are arranged in a V-shape to a state in which they are arranged in a straight line.

[0013] In this case, preferably, the multiple link members further have connecting members that connect the second link member and the split nut drive unit and rotate together with the second link member around a fixed pivot axis, wherein the angle of the connecting member relative to the second link member is kept constant when switching from a non-engaged state to an engaged state, as viewed from the direction in which the pivot axis extends. With this configuration, the force of the split nut drive unit can be transmitted to the second link member via the connecting member. In other words, the connecting member can function as a lever for driving the second link member. For this reason, the second link member can be easily driven by the split nut drive unit.

[0014] In the configuration in which the above-described plurality of link members have a first link member, preferably, the first link members are provided in multiple quantities so as to be arranged on both sides of the center of the tie bar, in a direction perpendicular to the direction of movement of the clamping split nut when viewed from the direction in which the tie bar extends. With this configuration, the first link members can be arranged in a more balanced manner with respect to the clamping split nut compared to the case in which the first link members are biased to one side of the center of the tie bar. As a result, the clamping split nut can be moved stably by the plurality of first link members.

[0015] In the molding apparatus according to the first aspect described above, preferably, the split nut drive unit is positioned outside the clamping split nut in a direction perpendicular to the direction of movement of the clamping split nut, when viewed from the direction in which the tie bar extends. With this configuration, it is not necessary to position the split nut drive unit in a position aligned with the clamping split nut in the direction in which the tie bar extends. In other words, it is not necessary to position the split nut drive unit in a location where space is relatively limited due to the extension of the tie bar. For this reason, the split nut drive unit can be easily positioned.

[0016] In the configuration for turning off the electric power source of the split nut drive unit described above, preferably, the split nut drive unit is composed of an electric air cylinder having an electric power source, or a motor cylinder having an electric motor which is the electric power source, and is configured to turn off the electric air cylinder or electric motor when multiple link members are locked by a toggle mechanism. With this configuration, the power consumption of the clamping device can be easily reduced by turning off the power to the electric air cylinder or the motor cylinder having an electric motor. [Effects of the Invention]

[0017] According to the present invention, as described above, the clamping device can generate a greater force to maintain the meshed state of the clamping split nut. [Brief explanation of the drawing]

[0018] [Figure 1] It is a schematic side view showing the overall configuration of a molding apparatus according to an embodiment. [Figure 2] It is a view taken along the arrow of the II-II line in Figure 1. [Figure 3] It is a perspective view showing the overall configuration of a mold clamping device of a molding apparatus according to an embodiment. [Figure 4] It is an exploded perspective view showing a split nut for mold clamping, a plurality of link members, and a split nut drive unit of the mold clamping device of the molding apparatus according to the embodiment. [Figure 5] It is a schematic plan view for explaining the driving of the split nut for mold clamping, the plurality of link members, and the split nut drive unit of the mold clamping device of the molding apparatus according to the embodiment. [Mode for Carrying Out the Invention]

[0019] Hereinafter, an embodiment embodying the present invention will be described based on the drawings.

[0020] [Embodiment] The configuration of the molding apparatus 100 according to the embodiment will be described with reference to Figure 1 to Figure 5. The molding apparatus 100 according to the embodiment is constituted by a die casting machine.

[0021] In each figure, the direction in which the tie bar 10 extends is indicated by the X direction. Among the X directions, the direction from the movable mold M1 toward the fixed mold M2 is indicated by the X1 direction, and the opposite direction is indicated by the X2 direction.

[0022] In each figure, the moving direction of the split nut for mold clamping 4 is indicated by the Z direction. The Z direction is a direction orthogonal to the X direction, and is also the vertical direction. Among the Z directions, the upper direction is indicated by the Z1 direction, and the lower direction is indicated by the Z2 direction.

[0023] In each figure, the direction orthogonal to both the X direction and the Z direction is indicated by the Y direction.

[0024] (Schematic Configuration of Molding Apparatus) The molding apparatus 100 shown in Figure 1 is a horizontal molding machine that performs molding by reciprocating a movable mold M1 horizontally relative to a fixed mold M2. The molding apparatus 100 is configured to manufacture molded products by injecting molten metal into the cavity in the mold M and allowing it to solidify.

[0025] The molding apparatus 100 comprises an injection device 101, a molding apparatus body 102 to which a mold M is attached, and a mold clamping device 103 having a mold clamping split nut 4.

[0026] A clamping device 103 is provided for each tie bar 10. Each clamping device 103 has a pair of clamping split nuts 4. The pair of clamping split nuts 4 are configured to restrict the movement of the movable die plate 12 relative to the tie bar 10 by engaging with the clamping groove 10a of the tie bar 10 when the mold M is closed.

[0027] Here, as shown in Figures 2 to 4, the clamping device 103 of this embodiment includes a toggle mechanism 5 having a plurality of link members 50. The toggle mechanism 5 of the clamping device 103 of this embodiment is configured to lock the plurality of link members 50 so that, when the clamping split nut 4 is engaged with the clamping groove 10a, the relative positions of the plurality of link members 50 are maintained against the force in the direction (Z direction) that would cause the clamping split nut 4 to try to open. Details of the clamping device 103 will be described later.

[0028] (Configuration of the injection device) Referring again to Figure 1, the injection device 101 comprises a cylindrical sleeve 101a, a plunger 101b, and a plunger drive device (not shown).

[0029] The sleeve 101a has a pouring spout 101c at its top. The sleeve 101a is configured so that when the mold M is closed, molten metal is poured into it through the pouring spout 101c by a pouring device including a ladle or the like.

[0030] The plunger 101b is configured to move forward and backward within the sleeve 101a. The plunger 101b is moved by a plunger drive device. The plunger 101b is configured to inject the molten metal into the cavity in the mold M by moving forward (in the X2 direction) with molten metal poured into the sleeve 101a.

[0031] (Configuration of the molding machine body) The molding apparatus body 102 comprises a plurality of tie bars 10, a fixed die plate 11, a movable die plate 12, a die plate drive device 13 for the movable die plate 12, and a mold release agent application device 14.

[0032] The tie bar 10 is provided with a clamping groove 10a. The clamping groove 10a is a groove with a continuous uneven shape formed at the end of the tie bar 10 in the X2 direction. The clamping groove 10a engages with the clamping split nut 4, thereby restricting the movement of the movable die plate 12 relative to the tie bar 10. With this configuration, when molten metal is injected into the cavity in the mold M, the clamping groove 10a prevents the movable mold M1 (movable die plate 12) from moving in the X2 direction along the tie bar 10 due to the mold opening force of the mold M.

[0033] The fixed die plate 11 is configured to hold the fixed mold M2. For example, the fixed mold M2 is fixed to the fixed die plate 11 by a clamping member. The injection device 101 is provided on the fixed die plate 11. The cylinder portion 15b of the clamping cylinder 15 is integrally provided on the fixed die plate 11. The piston portion 15a of the clamping cylinder 15 is integrally provided on the tie bar 10.

[0034] In detail, one clamping cylinder 15 is provided for each tie bar 10. For example, the clamping cylinder 15 is a hydraulic cylinder. The clamping cylinder 15 has a piston portion 15a and a cylindrical cylinder portion 15b that covers the piston portion 15a. The piston portion 15a is made up of the tie bar 10 itself. The head portion of the piston portion 15a is located near the end on the X1 direction side, which is opposite to the clamping groove portion 10a side of the tie bar 10. The cylinder portion 15b is made up of the fixed die plate 11 itself.

[0035] The clamping cylinder 15 is configured to clamp the mold M by closing the mold M, moving a pair of clamping split nuts 4 in the Z direction to engage with the tie bar 10, and then moving the piston portion 15a in the X1 direction. In detail, the clamping cylinder 15 is configured to move the tie bar 10, which has a piston portion 15a and a clamping groove portion 10a, in the X1 direction. As a result, the clamping cylinder 15 is configured to press the pair of clamping split nuts 4 (movable die plate 12) in the X1 direction with the clamping groove portion 10a, thereby restricting the movement of the movable die plate 12 in a direction away from the fixed mold M2 during molten metal injection.

[0036] The movable die plate 12 is configured to move along the tie bar 10 while holding the movable mold M1. For example, the movable mold M1 is fixed to the movable die plate 12 by a clamping member. The movable die plate 12 is provided with a clamping device 103. In detail, the clamping device 103 is fixed to the X2 direction side of the movable die plate 12 by fixing members such as bolts.

[0037] The die plate drive unit 13 supports the movable die plate 12 from below and is configured to move the movable die plate 12 forward and backward in the X direction along the tie bar 10. The die plate drive unit 13 is an electric drive unit.

[0038] The die plate drive device 13 comprises a servo motor 13a and a moving mechanism 13b driven by the servo motor 13a. The moving mechanism 13b has a movable die plate 12 installed from above and is configured to move the clamping split nut 4 together with the movable die plate 12 in the direction in which the tie bar 10 extends (X direction). The moving mechanism 13b includes a ball screw and is a feed mechanism that moves the clamping split nut 4 (die plate drive device 13) in the X direction. The moving mechanism 13b is driven by the servo motor 13a and is configured to accurately position the clamping split nut 4 (die plate drive device 13) in the X direction.

[0039] The die plate drive device 13 is configured to move the clamping split nut 4 to a predetermined position where the clamping split nut 4 and the clamping groove 10a face each other in the radial direction of the tie bar 10 using a servo motor 13a and a moving mechanism 13b. Subsequently, the clamping device 103 is configured to move the clamping split nut 4 in the Z direction to engage with the clamping groove 10a. The movable die plate 12 is moved by the die plate drive device 13 between the open die position shown in Figure 1 and the closed die position where the movable die M1 and the fixed die M2 are in contact or close to each other.

[0040] The coating device 14 is configured to apply a release agent to the mold M, which is opened by the die plate drive device 13. The coating device 14 includes a spray nozzle for ejecting the release agent and a nozzle moving device for moving the spray nozzle.

[0041] (Configuration of the clamping device) The clamping device 103 shown in Figures 2 to 5 comprises a first pivot shaft α, a second pivot shaft β, a third pivot shaft γ, a fourth pivot shaft δ, a housing 2, a split nut drive unit 3, a pair of clamping split nuts 4, and a toggle mechanism 5. The toggle mechanism 5 has a plurality of link members 50.

[0042] The clamping device 103 consists of a set of one first pivot shaft α, one second pivot shaft β, one third pivot shaft γ, one fourth pivot shaft δ, one split nut drive unit 3, one clamping split nut 4, and one toggle mechanism 5, with one set provided on one side and one side in the Z direction of the housing 2. The clamping device 103 is configured such that each toggle mechanism 5 on one side and the other side in the Z direction individually locks a plurality of link members 50.

[0043] The multiple link members 50 include a first link member 51, a second link member 52, and a connecting member 53. The first link member 51 is connected to the clamping split nut 4. The second link member 52 connects the first link member 51 to the split nut drive unit 3. The connecting member 53 connects the second link member 52 to the split nut drive unit 3.

[0044] The split nut drive unit 3 is a drive source that generates the force to move the clamping split nut 4. The force transmitted from the split nut drive unit 3 is in the following order from upstream to downstream: split nut drive unit 3, first rotation shaft α, connecting member 53, second rotation shaft β, second link member 52, third rotation shaft γ, first link member 51, fourth rotation shaft δ, and clamping split nut 4.

[0045] (Configuration of the first, second, third, and fourth rotation axes of the clamping device) The first rotation axis α, the second rotation axis β, the third rotation axis γ, and the fourth rotation axis δ each have a first rotation central axis α1, a second rotation central axis β1, a third rotation central axis γ1, and a fourth rotation central axis δ1, respectively. The first rotation central axis α1, the second rotation central axis β1, the third rotation central axis γ1, and the fourth rotation central axis δ1 are axes parallel to each other and extend in the Y direction. The second rotation central axis β1 is an example of the "rotation central axis" as defined in the claims.

[0046] The first rotating shaft α is provided between the connecting member 53 and the split nut drive unit 3, which are connected to each other, and rotatably supports the connecting member 53 and the split nut drive unit 3. The first rotating shaft α is not attached to the housing 2. Therefore, the first rotating shaft α is configured to move in a direction perpendicular to the Y direction in conjunction with the driving of the split nut drive unit 3 (see Figure 5).

[0047] Furthermore, the connecting member 53 and the split nut drive unit 3 are not fixed to the first drive shaft α. Therefore, the angle between the connecting member 53 and the split nut drive unit 3, when viewed from the direction in which the tie bar 10 extends (X direction), changes as the split nut drive unit 3 is driven (see Figure 5).

[0048] The second pivot shaft β is provided between the connecting member 53 and the second link member 52, which are connected to each other, and rotatably supports the connecting member 53 and the second link member 52. The second pivot shaft β is attached to the housing 2. Therefore, the second pivot shaft β does not move in a direction perpendicular to the Y direction as a result of the drive of the split nut drive unit 3 (see Figure 5).

[0049] Furthermore, the connecting member 53 and the second link member 52 are fixed to the second rotation axis β. Therefore, when the connecting member 53 rotates by a predetermined angle around the second rotation axis β in conjunction with the driving of the split nut drive unit 3, the second link member 52 also rotates by the same angle around the second rotation axis β as the connecting member 53. In other words, when viewed from the direction in which the tie bar 10 extends (X direction), the angle θ between the connecting member 53 and the second link member 52 is kept constant and does not change with the driving of the split nut drive unit 3 (see Figure 5). Note that the second rotation axis β, the connecting member 53, and the second link member 52 are separate components, but they may be constructed as an integral part.

[0050] The third pivot shaft γ is provided between the first link member 51 and the second link member 52, which are connected to each other, and rotatably supports the first link member 51 and the second link member 52. The third pivot shaft γ is not attached to the housing 2. Therefore, the third pivot shaft γ is configured to move in a direction perpendicular to the Y direction in conjunction with the driving of the split nut drive unit 3 (see Figure 5).

[0051] Furthermore, the first link member 51 and the second link member 52 are not fixed to the third rotation axis γ. Therefore, when viewed from the direction in which the tie bar 10 extends (X direction), the angle between the first link member 51 and the second link member 52 changes with the drive of the split nut drive unit 3 (see Figure 5).

[0052] The fourth rotation shaft δ is provided between the first link member 51 and the clamping split nut 4, which are connected to each other, and rotatably supports the first link member 51 and the clamping split nut 4. The fourth rotation shaft δ is not attached to the housing 2. Therefore, the fourth rotation shaft δ is configured to move in the Z direction, which is perpendicular to the Y direction, together with the clamping split nut 4 as the split nut drive unit 3 is driven (see Figure 5).

[0053] (Configuration of the clamping device housing) The housing 2 supports the clamping split nut 4 in a state where it can move in the Z direction. The housing 2 is configured to move the clamping split nut 4 in the Z direction by sliding while guiding it. The housing 2 has a pair of sliding surfaces 2a on both sides of the clamping split nut 4 in the Y direction that sandwich the clamping split nut 4. Although not shown, sliding plates are provided on both end faces of the clamping split nut 4 in the Y direction to contact the sliding surfaces 2a of the housing 2 and reduce sliding resistance.

[0054] (Configuration of the split nut drive unit of the mold clamping device) The split nut drive unit 3 is configured to move the clamping split nut 4 in the Z direction. The split nut drive unit 3 has an electric drive source (electric motor 30). More specifically, the split nut drive unit 3 is composed of a motor cylinder 3a having an electric motor 30, which is the electric drive source.

[0055] The motor cylinder 3a has a cylindrical cylinder portion 31 and a piston portion 32 that moves back and forth relative to the cylinder portion 31. One end of the motor cylinder 3a is supported by the housing 2 in a manner that allows it to rotate relative to the housing 2. The other end of the motor cylinder 3a is connected to a connecting member 53. The piston portion 32 protruding from the cylinder portion 31 has a first rotation shaft insertion hole 32a through which the first rotation shaft α is inserted. The piston portion 32 is connected to the connecting member 53 via the first rotation shaft α.

[0056] The clamping device 103 is configured to turn off the electric drive source (electric motor 30) so that no force is applied to the toggle mechanism 5 from the electric drive source (electric motor 30) when the multiple link members 50 are locked by the toggle mechanism 5. The locking of the toggle mechanism 5 will be described later.

[0057] In detail, the clamping device 103 is equipped with an opening / closing sensor S (see Figure 2) for detecting the opening and closing positions of the clamping split nut 4. For example, the opening / closing sensor S is an optical distance sensor that detects the distance to the clamping split nut 4 using light. The clamping device 103 is configured to turn off the electric motor 30 while the opening / closing sensor S detects that the clamping split nut 4 is in the closed position (engaged state). This turning off of the electric motor 30 based on the detection result of the opening / closing sensor S is performed by a control unit (not shown) including a CPU.

[0058] The phrase "while the opening / closing sensor S detects that the clamping split nut 4 is in the closed position (engaged state)" refers to the period during which the toggle mechanism 5 maintains a locked state for the multiple link members 50.

[0059] The split nut drive unit 3 is positioned outside the clamping split nut 4 in a direction (Y direction) perpendicular to the direction of movement of the clamping split nut 4 (Z direction), when viewed from the direction in which the tie bar 10 extends (X direction). In other words, the split nut drive unit 3 is positioned outside the housing 2 so as not to interfere with the tie bar 10.

[0060] (Configuration of the clamping nut for the clamping device) The clamping split nuts 4 are configured to restrict the movement of the movable die plate 12 relative to the tie bar 10 by engaging with the clamping groove 10a of the tie bar 10 when the mold M is closed. The clamping split nuts 4 are a pair of members arranged to face each other in the Z direction when viewed from the direction in which the tie bar 10 extends (X direction).

[0061] The clamping split nut 4 has an arc-shaped tooth portion 40 (projection) that engages with the clamping groove portion 10a of the tie bar 10, and a fourth rotation shaft insertion hole 41 through which the fourth rotation shaft δ is inserted. The fourth rotation shaft insertion hole 41 is located on the side opposite to the tooth portion 40 in the Z direction.

[0062] (Configuration of the toggle mechanism of the clamping device) As described above, the toggle mechanism 5 has multiple link members 50. The multiple link members 50 are configured to transmit the force of the split nut drive unit 3 to the clamping split nut 4.

[0063] Furthermore, as described above, each of the multiple link members 50 includes a first link member 51, a second link member 52, and a connecting member 53.

[0064] The first link member 51 is connected to the clamping split nut 4 via the fourth pivot shaft δ. The first link member 51 has a fourth pivot shaft insertion hole 51a through which the fourth pivot shaft δ is inserted, and a third pivot shaft insertion hole 51b through which the third pivot shaft γ is inserted. The first link member 51 is formed in an elongated straight shape when viewed from the Y direction.

[0065] Multiple (two) first link members 51 are provided so as to be positioned on both sides of the center line C1 of the tie bar 10, in the direction (Y direction) perpendicular to the direction of movement of the clamping split nut 4 (Z direction), when viewed from the direction in which the tie bar 10 extends (X direction). In short, the first link members 51 are composed of multiple members that are well-balanced with respect to the clamping split nut 4 in the Y direction.

[0066] The second link member 52, together with the connecting member 53, connects the first link member 51 and the split nut drive unit 3. That is, the second link member 52 is connected to the first link member 51 via the third pivot shaft γ. The second link member 52 is also connected to the connecting member 53 via the second pivot shaft β. The second link member 52 has a third pivot shaft insertion hole 52a through which the third pivot shaft γ is inserted, and a second pivot shaft insertion hole 52b through which the second pivot shaft β is inserted.

[0067] The second link member 52 is formed in an elongated straight shape when viewed from the Y direction. Furthermore, when viewed from the X direction, which is the direction in which the tie bar 10 extends, the second link member 52 is formed in an E shape with two recesses for which one first link member 51 is placed. The clamping split nut 4 is also formed in an E shape, similar to the second link member 52, with two recesses for which one first link member 51 is placed at positions corresponding to the two recesses of the second link member 52.

[0068] Here, the toggle mechanism 5 is configured to lock the multiple link members 50 by arranging them in a straight line while the clamping split nut 4 is engaged with the clamping groove 10a of the tie bar 10.

[0069] In detail, the first link member 51 and the second link member 52 are configured to be switched by the split nut drive unit 3 from a non-engaged state in which the connection position of the first link member 51 and the second link member 52 is bent in a V-shape when the engagement between the clamping split nut 4 and the clamping groove 10a is released, to an engaged state in which the first link member 51 and the second link member 52 are arranged in a straight line.

[0070] More specifically, the clamping device 103 is configured to lock the first link member 51 and the second link member 52 together by arranging them in a straight line such that the angle between the first link member 51 and the second link member 52 around the third pivot axis γ is approximately 180 degrees. In short, the clamping device 103 is configured to toggle-lock the clamping split nut 4 using the first link member 51 and the second link member 52. As a result, the clamping device 103 maintains the engaged state in which the clamping split nut 4 engages with the clamping groove 10a by the toggle lock using the first link member 51 and the second link member 52.

[0071] In other words, the engagement state in which the clamping split nut 4 engages with the clamping groove 10a is not maintained by the split nut drive unit 3, but by the toggle mechanism 5. Therefore, as described above, the clamping device 103 can turn off the electric drive source (electric motor 30) of the split nut drive unit 3 when it is engaged.

[0072] The connecting member 53 connects the second link member 52 and the split nut drive unit 3. The connecting member 53 has a second pivot shaft insertion hole 53a through which the second pivot shaft β is inserted, and a first pivot shaft insertion hole 53b through which the first pivot shaft α is inserted. As described above, the connecting member 53 is configured to rotate together with the second link member 52 around the second pivot center axis β1, whose position is fixed by the housing 2.

[0073] The connecting member 53 is configured such that when the clamping split nut 4 switches from a non-engaged state to an engaged state, the angle θ (see Figure 5) with respect to the second link member 52 is kept constant when viewed from the direction in which the second rotational center axis β1 extends (Y direction). In one example, the angle θ is acute. The connecting member 53 functions as a lever to move the second link member 52 when the split nut drive unit 3 rotates the second link member 52.

[0074] (Effects of the embodiment) In this embodiment, the following effects can be obtained.

[0075] In this embodiment, as described above, a mold clamping device 103 is provided, which includes a pair of mold clamping split nuts 4, a split nut drive unit 3, and a toggle mechanism 5 having a plurality of link members 50 that transmit the force of the split nut drive unit 3 to the mold clamping split nuts 4. The toggle mechanism 5 locks the plurality of link members 50 so that when the mold clamping split nuts 4 are engaged with the mold clamping groove 10a, the relative positions of the plurality of link members 50 are maintained against the force that tries to open the mold clamping split nuts 4 and release the engagement. As a result, when a force is generated that tries to open the mold clamping split nuts 4 and release the engagement during injection of molding material into the mold M, the engaged state of the mold clamping split nuts 4 can be maintained by the force of the locked plurality of link members 50 of the toggle mechanism 5, rather than by the force of the split nut drive unit 3. Therefore, compared to conventional clamping devices that maintain the meshing state by a cylinder that drives the half nut, the clamping device 103 can generate a greater force to maintain the meshing state of the clamping split nut 4.

[0076] In this embodiment, as described above, the toggle mechanism 5 is configured to lock the multiple link members 50 by arranging them linearly when engaged. This makes it easy to lock the multiple link members 50 by arranging them linearly.

[0077] In this embodiment, as described above, one clamping device 103 is provided on one side of the pair of clamping split nuts 4, and the toggle mechanism 5 of each clamping device 103 is configured to lock multiple link members 50. This means that, as in the conventional method, when multiple clamping split nuts are driven by one split nut drive unit, a structure such as gears is required to transmit driving force from one split nut drive unit to multiple clamping split nuts. However, when only the clamping split nuts 4 are driven by one split nut drive unit 3, the above-mentioned structure such as gears is unnecessary. Therefore, the configuration of the device for transmitting driving force can be simplified.

[0078] In this embodiment, as described above, the split nut drive unit 3 has an electric drive source, and is configured to turn off the electric drive source so that no force is applied from the electric drive source to the toggle mechanism 5 when the multiple link members 50 are locked by the toggle mechanism 5. This makes it possible to turn off the electric drive source when the multiple link members 50 are locked by the toggle mechanism 5, thereby reducing the power consumption of the clamping device 103.

[0079] In this embodiment, as described above, the plurality of link members 50 have a first link member 51 connected to the clamping split nut 4 and a second link member 52 connecting the first link member and the split nut drive unit 3. The first link member 51 and the second link member 52 are configured to be switched by the split nut drive unit 3 from a non-engaged state in which the connection position of the first link member 51 and the second link member 52 is bent in a V shape when the engagement between the clamping split nut 4 and the clamping groove 10a is released, to an engaged state in which the first link member 51 and the second link member 52 are arranged in a straight line (see Figure 5). By doing so, the plurality of link members 50 can be locked more easily by switching the first link member 51 and the second link member 52 from a V-shaped arrangement to a straight arrangement.

[0080] In this embodiment, as described above, the multiple link members 50 further have a connecting member 53 that connects the second link member 52 and the split nut drive unit 3, and rotates together with the second link member 52 around a fixed second rotational axis β1. The connecting member 53 is configured such that when switching from a non-engaged state to an engaged state, the angle of the connecting member 53 with respect to the second link member 52 is kept constant when viewed from the direction in which the second rotational axis β1 extends. This allows the force of the split nut drive unit 3 to be transmitted to the second link member 52 via the connecting member 53. In other words, the connecting member 53 can function as a lever for driving the second link member 52. Therefore, the second link member 52 can be easily driven by the split nut drive unit 3.

[0081] In this embodiment, as described above, multiple first link members 51 are provided so as to be positioned on both sides of the center of the tie bar 10, in a direction perpendicular to the direction of movement of the clamping split nut 4 when viewed from the direction in which the tie bar 10 extends. This allows the first link members 51 to be positioned more evenly with respect to the clamping split nut 4 compared to the case where the first link members 51 are positioned biased to one side of the center of the tie bar 10. As a result, the clamping split nut 4 can be moved stably by the multiple first link members 51.

[0082] In this embodiment, as described above, the split nut drive unit 3 is positioned outside the clamping split nut 4 in a direction perpendicular to the direction of movement of the clamping split nut 4 when viewed from the direction in which the tie bar 10 extends. This eliminates the need to position the split nut drive unit 3 in a position aligned with the clamping split nut 4 in the direction in which the tie bar 10 extends. In other words, it eliminates the need to position the split nut drive unit 3 in a location where space is relatively limited due to the extension of the tie bar 10. Therefore, the split nut drive unit 3 can be easily positioned.

[0083] In this embodiment, as described above, the split nut drive unit 3 is composed of a motor cylinder 3a having an electric motor 30, which is the electric drive source, and is configured to turn off the electric motor 30 when the multiple link members 50 are locked by the toggle mechanism 5. This makes it easy to reduce the power consumption of the clamping device 103 by turning off the power to the motor cylinder 3a having the electric motor 30.

[0084] [Differentiation] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than the description of the embodiments above, and further includes all modifications (modifications) within the meaning and scope equivalent to the claims.

[0085] For example, in the above embodiment, an example was shown in which the molding apparatus is configured using a die-casting machine, but the present invention is not limited thereto. In the present invention, the molding apparatus may be configured using an injection molding apparatus that injects resin, or the like.

[0086] Furthermore, although the above embodiment shows an example in which the molding apparatus is configured as a horizontal molding apparatus, the present invention is not limited thereto. In the present invention, the molding apparatus may also be configured as a vertical molding apparatus.

[0087] Furthermore, although the above embodiment shows an example in which the split nut drive unit is configured with a motor cylinder, the present invention is not limited to this. In the present invention, the split nut drive unit may be configured with an electric air cylinder or the like.

[0088] Furthermore, while the above embodiment shows an example in which the clamping device is configured such that the split nut drive unit closes by retracting (reversing) the motor cylinder, the present invention is not limited to this. In the present invention, the clamping device may be configured such that the split nut drive unit closes by extending (advancing) the motor cylinder.

[0089] Furthermore, although the above embodiment shows an example in which multiple link members are composed of three members (first link member, second link member, and connecting member), the present invention is not limited to this. In the present invention, multiple link members may be composed of two members, or four or more members.

[0090] Furthermore, although the above embodiment shows an example in which multiple link members are arranged in a straight line while the multiple link members are locked, the present invention is not limited to this. In the present invention, instead of arranging the multiple link members in a straight line while the multiple link members are locked, they may be arranged at a predetermined angle.

[0091] Furthermore, although the above embodiment shows an example in which the electric power source of the split nut drive unit is turned off while multiple link members are locked by the toggle mechanism, the present invention is not limited to this. In the present invention, even when multiple link members are locked by the toggle mechanism, the electric power source of the split nut drive unit may be kept on without being turned off.

[0092] Furthermore, in the above embodiment, an example was shown in which the split nut drive unit (motor cylinder) is positioned outside the mold clamping split nut in a direction perpendicular to the direction of movement of the mold clamping split nut when viewed from the direction in which the tie bar extends. However, the present invention is not limited to this. In the present invention, the split nut drive unit (motor cylinder) may be positioned inside the mold clamping split nut in a direction perpendicular to the direction of movement of the mold clamping split nut when viewed from the direction in which the tie bar extends. For example, the split nut drive unit (motor cylinder) may be positioned on the Z1 (Z2) side, which is the direction of movement of the mold clamping split nut. [Explanation of Symbols]

[0093] 30% Nut Drive Unit 3a Motor Cylinder Type 4 clamping split nut 5. Toggle mechanism 10 Tie Bars 10a Clamping groove 12 movable die plates 30 Electric motors 50 Link members 51 First link member 52 Second link member 53 Connecting Member 100 Molding equipment 103 Mold clamping device C1 (center of the tie bar) M mold M1 Mobile Mold β1 Second rotational axis (rotational axis)

Claims

1. A tie bar provided with a clamping groove, A movable die plate that moves along the tie bar while holding the movable mold, A clamping device provided on the movable die plate includes a pair of clamping split nuts that engage with the clamping grooves when the mold is closed to restrict the movement of the movable die plate relative to the tie bar, a split nut drive unit that moves the clamping split nuts, and a toggle mechanism having a plurality of link members that transmit the force of the split nut drive unit to the clamping split nuts, A molding apparatus in which the toggle mechanism is configured to lock the plurality of link members so that, when the clamping split nut is engaged with the clamping groove, the relative positions of the plurality of link members are maintained against a force that would cause the clamping split nut to open and disengage.

2. The molding apparatus according to claim 1, wherein the toggle mechanism is configured to lock the plurality of link members by arranging the plurality of link members in a straight line when the meshing state is reached.

3. The clamping device is provided on one and the other of the pair of clamping split nuts. The molding apparatus according to claim 1, wherein the toggle mechanism of each of the clamping devices is configured to lock the plurality of link members.

4. The aforementioned split nut drive unit has an electric drive source, The molding apparatus according to claim 1, wherein the electric drive source is configured to be turned off so that no force is applied to the toggle mechanism from the electric drive source when the plurality of link members are locked by the toggle mechanism.

5. The plurality of link members include a first link member connected to the clamping split nut and a second link member connecting the first link member and the split nut drive unit. The molding apparatus according to claim 2, wherein the first link member and the second link member are configured to be switched by the split nut drive unit from a non-engaged state in which the connection position of the first link member and the second link member is bent in a V-shape when the engagement between the mold clamping split nut and the mold clamping groove is released, to the engaged state in which the first link member and the second link member are arranged in a straight line.

6. The plurality of link members further have connecting members that connect the second link member and the split nut drive unit, and that rotate together with the second link member around a fixed pivot axis. The molding apparatus according to claim 5, wherein the connecting member is configured such that, when switching from the non-engaged state to the engaged state, the angle with respect to the second link member is kept constant when viewed from the direction in which the rotational center axis extends.

7. The molding apparatus according to claim 5, wherein a plurality of the first link members are provided so as to be arranged on both sides of the center of the tie bar, in a direction perpendicular to the direction of movement of the mold clamping split nut, when viewed from the direction in which the tie bar extends.

8. The molding apparatus according to claim 1, wherein the split nut drive unit is positioned outside the mold clamping split nut in a direction perpendicular to the direction of movement of the mold clamping split nut, as viewed from the direction in which the tie bar extends.

9. The split nut drive unit is composed of an electric air cylinder having the electric drive source, or a motor cylinder having an electric motor which is the electric drive source. The molding apparatus according to claim 4, wherein the electric air cylinder or the electric motor is configured to be turned off when the plurality of link members are locked by the toggle mechanism.

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