JPH0572421U - Clamping device for injection molding machine - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the work efficiency of injection molding by shortening the time required to open and close the molds 36, 40 of the injection molding machine. [Structure] Immediately before the molds 36 and 40 are clamped, the lock block 76 is moved to a closed position where the hole 63 of the moving plate 45 is closed, and immediately after the molds 36 and 40 are released from the mold clamp. The lock block 76 is moved to a separated position separated from the hole 63. Here, since the lock block 76 is composed of a pair of lock bodies, the moving distance between the closed position and the separated position is shortened as compared with the case where the lock block is composed of one block, and the work efficiency is improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mold clamping device that performs mold clamping and opening / closing of a mold in an injection molding machine using separate cylinders.

[0002]

[Prior Art]

 As a mold clamping device for a conventional injection molding machine, the ones shown in, for example, FIGS. 5 and 6 are known. This one has a frame 11 having a lower die 12 fixed to the upper surface thereof, and a plurality of guide tubes 13 provided on the frame 11 are capable of vertically moving a central portion of a connecting rod 14 extending in the vertical direction. It is supported. At the upper end of these connecting rods 14 is fixed a horizontal die plate 15 having an upper mold 16 paired with the lower mold 12 fixed to the lower surface thereof, while at the lower ends of these connecting rods 14, a horizontal moving plate 15 is fixed. 17 is fixed. Further, a plurality of vertical opening / closing cylinders 19 are attached to the lower surface of the frame 11, and the tips of piston rods 18 of these opening / closing cylinders 19 are connected to the moving plate 17. As a result, the opening / closing cylinders 19 are Is operated, the moving plate 17, the connecting rod 14, the die plate 15, and the upper mold 16 move integrally in the vertical direction, and the upper mold 16 approaches and separates from the lower mold 12. Lower molds 16 and 12 open and close. A mold clamping cylinder 22 fixed to the lower surface of the frame 11 is located between the frame 11 and the die plate 17, and the piston rod 20 of this mold clamping cylinder 22 is inserted into a hole 21 formed in the moving plate 17. It is possible. Reference numeral 23 denotes one lock block that can move while slidingly contacting the surface (upper surface) of the moving plate 17 on the side facing the mold clamping cylinder 22, and this lock block 23 has a lateral movement of the hole 21. The tip of the piston rod 24 of one air cylinder 25 mounted on the plate 17 is connected. When the air cylinder 25 operates, the lock block 23 moves between a closed position H (see FIG. 6) that closes the hole 21 and a separated position R (see FIG. 5) that is separated from the hole 21.

When the upper and lower molds 16 and 12 are opened and closed by this mold clamping device, first, the piston rod 18 of the opening and closing cylinder 19 is projected from the state shown in FIG. 5 to move the moving plate 17, The connecting rod 14 and the die plate 15 are lowered until the upper die 16 contacts the lower die 12. As a result, the upper and lower molds 16 and 12 are closed. Next, the piston rod 24 of the air cylinder 25 is projected to move the lock block 23 to the closed position H, and the hole 21 is closed by the lock block 23. Next, the piston rod 20 of the mold clamping cylinder 22 is projected and the tip thereof is brought into contact with the lock block 23. When the piston rod 20 of the mold clamping cylinder 22 is further attempted to project in this state, the piston rod 20 is moved downward from the piston rod 20 to the upper mold 16 through the lock block 23, the moving plate 17, the connecting rod 14, and the die plate 15. The force directed to is transmitted, whereby the upper die 16 is pressed against the lower die 12 and the upper die 16 and 12 are clamped. After that, the plastic material is injected and filled into the cavities in the upper and lower molds 16 and 12 from the injection molding unit. Next, after the piston rod 20 of the mold clamping cylinder 22 retracts, the piston rod 24 of the air cylinder 25 retracts, and the lock block 23 moves from the closed position H to the separated position R. Next, the piston rod 18 of the opening / closing cylinder 19 retracts, the moving plate 17, the connecting rod 14, and the die plate 15 rise, and the upper die 16 separates from the lower die 12, and the upper die 16 and the lower die 16 Be released. At this time, the piston rod 20 of the mold clamping cylinder 22 is inserted into the opened hole 21 as the lock block 23 moves to the separated position R. In this way, when the upper and lower molds 16 and 12 are opened, the molded product is taken out from the upper and lower molds 16 and 12.

Further, as a mold clamping device for an injection molding machine similar to this, there is also known one as described in Japanese Utility Model Publication No. 1-114544.

[0005]

[Problems to be solved by the device]

 However, in such a conventional mold clamping device for an injection molding machine, one lock block 23 is moved between the closed position H and the separated position R by one air cylinder 25. Therefore, there is a problem in that the moving distance of the lock block 23 becomes long, and as a result, it takes time to move the lock block 23 and the work efficiency decreases.

An object of the present invention is to provide a mold clamping device for an injection molding machine, which can improve work efficiency by shortening a moving distance of a lock block.

[0007]

[Means for Solving the Problems]

 Such a purpose is to provide a frame, one mold fixed to the frame, and a movable die plate having a frame supported by the other mold attached thereto. The moving plate connected to the die plate via the connecting rod and the moving plate attached to the frame, the connecting rod, the die plate, and the other mold are integrally moved to move the other mold to the one mold. An open / close cylinder that opens and closes the mold by approaching and separating it, and a mold that is attached to the frame so that it is located between the frame and the moving plate, and the moving part can be inserted into the hole formed in the moving plate. The tightening cylinder, a lock block that can move while sliding on the surface of the moving plate that faces the mold clamping cylinder, and a closing position that closes the hole in the lock block. In the mold clamping device of the injection molding machine, the lock blocks are located close to each other when in the closed position and on both sides of the hole when in the separated position. This can be achieved by comprising a pair of lock bodies located, and by moving the lock bodies toward and away from each other by the moving means.

[0008]

[Action]

 When closing both molds with this mold clamping device, first open and close the moving cylinder, move the moving plate, connecting rod, and die plate integrally, and move the other mold to one mold. To close the one and the other mold. Next, the pair of lock bodies located on both sides of the hole are moved to the closed position by the moving means, and the pair of lock bodies are brought close to each other to close the hole. At this time, since the moving distance of the lock body is shorter than the moving distance when the lock block is composed of one block, the moving time becomes shorter. Next, the mold clamping cylinder is operated to bring its moving portion into contact with the lock body (lock block) whose hole is closed. If the mold clamping cylinder continues to operate in this state, the force from the moving part to the other mold is transmitted to the other mold through the lock block, the moving plate, the connecting rod, and the die plate. The two molds are clamped by pressing the one mold to the other mold. After that, the plastic material is injected and filled from the injection molding unit into the cavities in both molds. Next, the mold clamping cylinder is operated to separate the moving part from the lock body, and the moving means is operated to move the lock body from the closed position to the separate positions on both sides of the hole. Also at this time, since the moving distance of the lock body is shorter than that when one lock block is used, the moving time is shortened and the efficiency of the opening / closing work of the mold is improved. Next, the opening / closing cylinder operates to move the moving plate, the connecting rod, and the die plate, the other mold is separated from the one mold, and both molds are opened. At this time, the moving part of the mold clamping cylinder is inserted into the open hole when the lock body moves to the separated position. When both molds are opened in this manner, the molded product is taken out from both molds.

Further, according to the second aspect of the invention, since each lock body starts moving toward the closed position and the separated position by the cylinder at the moment when the lock body is separated from the moving portion of the mold clamping cylinder, The time for moving is further shortened and the work efficiency is improved. Further, according to the third aspect, when the moving portion moves, vibration does not occur due to the sliding contact between the moving portion and the lock body. Further, according to the structure described in claim 4, it is possible to mitigate the impact generated when the lock body is closed and stopped at the separated position.

[0010]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1, 2 and 3, reference numeral 31 denotes a frame, which is composed of a frame main body 32 and a horizontal rectangular support plate 33 fixed to the center of the frame main body 32 in the height direction. ing. A lower mold 36 as one mold is fixed to the upper surface of the central portion of the support plate 33. Cylindrical guide tubes 37 extending downward are integrally formed at the four corners of the support plate 33, and the central portions of the vertically extending connecting rods 38 are slidable in the guide tubes 37. It has been inserted. A horizontal rectangular die plate 39 is attached to the upper ends of these four connecting rods 38. As a result, this die plate 39 can be moved to the frame 31 via the connecting rod 38 (it can be moved up and down). ) Will be supported. An upper die 40 as the other die is attached to the lower surface of the center of the die plate 39, and the upper die 40 forms a pair with the lower die 36, and when closed, the inner die together with the lower die 36. To form a cavity (not shown) into which the plastic material is injected and filled. An injection unit 41 for injecting and filling a plastic material into the cavities formed by the upper and lower molds 40 and 36 is fixed to the upper surface of the center of the die plate 39. A rectangular horizontal moving plate 45 is attached to the lower ends of the four connecting rods 38 by nuts 44, so that the moving plate 45 is connected to the die plate 39 via the connecting rod 38. become.

Reference numeral 48 denotes a pair of vertically extending opening / closing cylinders whose head side is attached to the lower surface of the support plate 33, and a cylinder body 49 of these opening / closing cylinders 48 has a cylinder chamber divided into two chambers by a piston 50. 51 is provided. The tip of a downwardly extending piston rod 52 formed integrally with the piston 50 is inserted and fixed in a notch 53 formed in the moving plate 45. When pressure fluid, for example pressure oil, is supplied into the cylinder chamber 51 from the supply / discharge port 54 or 55 and the piston rod 52 projects or retracts, the moving plate 45, the connecting rod 38, and the die plate 39 are integrated. The upper mold 40 is moved closer to and separated from the lower mold 36, and the two molds 40 and 36 are opened and closed. The head side of a vertically extending mold clamping cylinder 58 is fixed to the lower surface of the central portion of the support plate 33, so that the mold clamping cylinder 58 is positioned between the support plate 33 of the frame 31 and the moving plate 45. Becomes The mold clamping cylinder 58 has a cylinder body 60 having a cylinder chamber 59 formed therein, and a piston 61 that divides the cylinder chamber 59 into two chambers is slidably inserted into the cylinder chamber 59. ing. A piston rod 62 as a moving portion extending downward is integrally formed with the piston 61, and the piston rod 62 is provided in a hole 63 formed in the moving plate 45 when the moving plate 45 moves up. It can be inserted. When a pressure fluid, for example pressure oil, is supplied to the cylinder chamber 59 of the mold clamping cylinder 58 from the supply / discharge port 64 or 65 into the cylinder chamber 59, the piston rod 62 projects or retracts.

68 and 69 are a pair of guide blocks provided so as to sandwich the hole 63, and these guide blocks 68 and 69 are fixed to the upper surface of the moving plate 45. Guide grooves 70, 71 are formed on the inner surfaces of the guide blocks 68, 69 facing each other, and a groove 72 continuous with the guide grooves 70, 71 is also formed on the upper surface of the moving plate 45. 74 and 75 are a pair of lock bodies, and these lock bodies 74 and 75 move while slidingly contacting the inner surfaces of the guide grooves 70 and 71 of the guide blocks 68 and 69 and the upper surface of the groove 72 of the moving plate 45. Approach and separate. The lock bodies 74 and 75 described above form a lock block 76 as a whole. 79 and 80 are a pair of brackets fixed to the upper surface of the moving plate 45 outside the lock bodies 74 and 75. These brackets 79 and 80 have a pair of air-driven cylinders located on both sides of the hole 63. 81 and 82 are attached. The lock bodies 74 and 75 are connected to the tips of the piston rods 83 and 84 of the cylinders 81 and 82, respectively. As a result, when the cylinders 81 and 82 are operated, the lock bodies 74 and 75 are in contact with each other and the holes 63 are formed. It moves between a closed position H that closes the hole and a separated position R that is separated from the hole 63 on both sides. Further, rollers 87 and 88 are rotatably supported at the tips of the lock bodies 74 and 75 close to each other via pins 85 and 86, and these rollers 87 and 88 are clamped between the lock bodies 74 and 75. When the piston rod 62 of the cylinder 58 is in position, it can make rolling contact with both sides of this piston rod 62. The above-mentioned pair of cylinders 81 and 82 collectively constitute a moving means 89 for moving the lock block 76 between the closed position H and the separated position R.

Reference numerals 91 and 92 denote a plurality of cushion bodies attached to the moving plate 45 through guide blocks 68 and 69. The cushion bodies 91 and 92 have the lock bodies 74 and 75 in the vicinity of the closed position H. When the lock bodies 74 and 75 come into contact with each other, their moving speed is reduced. Further, 93 and 94 are a plurality of cushion bodies attached to the moving plate 45 via brackets 79 and 80, and the lock bodies 74 and 75 described above are attached to these cushion bodies 93 and 94 at the separation position R. When the lock bodies 74 and 75 come close to each other, their moving speed is reduced. As shown in FIG. 4, each of the cushion bodies 91, 92, 93, and 94 has a cylinder body 96 into which a receiving body 95 is screwed, and is slidably inserted into a cylinder chamber 97 of the cylinder body 96. The piston 98 is formed with a throttle hole 99 that connects the cylinder chambers 97 partitioned by the piston 98 into two. A piston rod 100 protruding from the cylinder body 96 is integrally formed with the piston 98, and a spring 101 is interposed between the piston 98 and the receiving body 95. The cylinder chamber 97 is filled with cushioning oil.

Next, the operation of the embodiment of the present invention will be described. Now, the piston rod 52 of the opening / closing cylinder 48 is retracted to the stroke end, and the upper mold 40 is separated from the upper mold 36 above the lower mold 36, as shown in FIG. Is inserted in the hole 63. At this time, since the piston rods 83, 84 of the cylinders 81, 82 are provided with the air force in the protruding direction, the lock bodies 74, 75 are locked by the cylinders 81, 82 so that the rollers 87, 88 are located on both sides of the piston rod 62. Are urged so as to approach each other in the state of abutting against each other.

Next, when closing the molds 40 and 36 by closing, first, the pressure fluid is supplied from the supply / discharge port 54 into the cylinder chamber 51 of the opening / closing cylinder 48 so that the piston rod 52 is projected. It As a result, the moving plate 45, the connecting rod 38, and the die plate 39 are lowered while being guided integrally by the guide cylinder 37, whereby the upper die 40 approaches the lower die 36, and both die 40, 36 gradually closes. When the moving plate 45 descends, the block bodies 74 and 75 move in the axial direction of the piston rod 62, but at this time, the rollers 87 and 88 rotatably supported by the lock bodies 74 and 75 are attached to the piston rod 62. Since the rolling contact is made, the piston rod 62 and the lock bodies 74 and 75 do not come into sliding contact with each other, so that the vibration due to the sliding contact does not occur. Further, while the moving plate 45 is descending, the piston rod 62 comes out upward from between the hole 63 and the lock bodies 74 and 75 and separates from the moving plate 45 and the lock bodies 74 and 75. Since 74 and 75 are urged toward each other by the cylinders 81 and 82 as described above, the lock bodies 74 and 75 move toward the closed position H at the moment when the piston rod 62 is separated from the lock bodies 74 and 75. The movement is started, which shortens the movement time and improves work efficiency. Then, the movement of the lock bodies 74 and 75 is stopped when the inner surfaces of the lock bodies 74 and 75 come into contact with each other immediately above the hole 63, whereby the lock bodies 74 and 75 close the hole 63 from above. To do. Here, when the lock bodies 74 and 75 move to the vicinity of the closed position H, the lock bodies 74 and 75 come into contact with the piston rods 100 of the cushion bodies 91 and 92 attached to the guide blocks 69 and 69. The moving speed of the lock bodies 74 and 75 is rapidly reduced by the oil passing through the throttle hole 99. As a result, even if the inner surfaces of the lock bodies 74 and 75 come into contact with each other as described above, the moving speed of the lock bodies 74 and 75 at the time of contact is significantly reduced, so that when they come into contact (when stopped) The impact generated in the is effectively mitigated. At this time, the moving distance of the lock bodies 74 and 75 is shorter than the moving distance when the lock block is composed of one block, so that the moving time is shortened and the work efficiency is improved. When the upper mold 40 comes into contact with the lower mold 36 and both molds 40, 36 are closed, the operation of the opening / closing cylinder 48 is stopped, and a cavity is formed in both molds 40, 36. To be done.

Next, pressure fluid is supplied from the supply / discharge port 64 of the mold clamping cylinder 58 into the cylinder chamber 59, and the piston 61 and the piston rod 62 move downward. The movement of the piston 61 and the piston rod 62 stops when the lower end of the piston rod 62 comes into contact with the upper surfaces of the lock bodies 74 and 75 that close the hole 63, but continues after this contact. Since pressurized fluid is supplied from the supply / discharge port 64 to the cylinder chamber 59, the piston 61 and the piston rod 62 move toward the upper mold 40 and the lower mold 36 via the moving plate 45, the connecting rod 38, and the die plate 39. Is transmitted. As a result, the upper mold 40 is strongly pressed against the lower mold 36, and the molds 40 and 36 are clamped. At this time, the cylinders 81 and 82 are actuated to apply an air force in the retracting direction to the piston rods 83 and 84, which causes the lock bodies 74 and 75 to move from the closed position H to the separated position R (the direction where they are separated from each other). Heading toward) Applying biasing force. However, at this time, since both lock bodies 74 and 75 are pressed against the moving plate 45 by the piston rod 62 of the mold clamping cylinder 58, these lock bodies 74 and 75 cannot move toward the separated position R. .. After that, the injection unit 41 injects and fills the cavities in the molds 40 and 36 with the plastic material.

Next, pressure fluid is supplied from the supply / discharge port 65 of the mold clamping cylinder 58 into the cylinder chamber 59 to move the piston 61 and the piston rod 62 upward. As a result, the piston rod 62 is disengaged from the lock bodies 74 and 75. As described above, since the urging force toward the separated position R is applied to the lock bodies 74 and 75 from the cylinders 81 and 82, the piston rod 62 is removed. When the lock bodies 74 and 75 are separated from the lock bodies 74 and 75, the lock bodies 74 and 75 start moving toward the separated position R, whereby the movement time is shortened and the work efficiency is improved. Then, when the lock bodies 74, 75 start moving and move by a predetermined short distance, a limit switch (not shown) detects the movement of the lock bodies 74, 75 and moves them to the feed / discharge port 65 of the mold clamping cylinder 58. Stop the supply of pressurized fluid. Therefore, the piston rod 62 of the mold clamping cylinder 58 is stopped at the position where the lower end thereof is separated from the upper surfaces of the lock bodies 74 and 75 by a slight distance. When the tightening is released, the moving distance of the piston rod 62 is shortened and the work efficiency is improved. Then, when the lock bodies 74, 75 move to the vicinity of the separated position R, the lock bodies 74, 75 come into contact with the cushion bodies 93, 94, and the moving speed thereof is decelerated rapidly as described above. The lock bodies 74 and 75 stop when they reach the separated position R, but since the moving speed of the lock bodies 74 and 75 at this stop time is greatly reduced by the cushion bodies 93 and 94, the generated shock is generated. Is effectively mitigated.

Next, pressure fluid is supplied to the cylinder chamber 51 via the supply / discharge port 55 of the opening / closing cylinder 48, and the piston rod 52 retracts. As a result, the moving plate 45, the connecting rod 38, and the die plate 39 are integrally moved upward, the upper mold 40 is separated from the lower mold 36, and both molds 40, 36 are opened. At this time, the piston rod 62 of the mold clamping cylinder 58 is inserted into the hole 63 opened by the lock bodies 74 and 75 moving to the separated position R. When both the molds 40 and 36 are opened in this manner, the molded product is taken out from the molds 40 and 36. At this time, the piston rods 83 and 84 of the cylinders 81 and 82 project and are moved until the lock bodies 74 and 75, more specifically the rollers 87 and 88, come into contact with both sides of the piston rod 62. Then, even after this contact, the air force for urging the cylinders 81 and 82 to urge the lock bodies 74 and 75 toward each other is applied. The above is one cycle of the operation of one embodiment of the present invention, and thereafter, this cycle is repeated to successively mold the molded products.

In the embodiment described above, the cylinder body 60 of the mold clamping cylinder 58 is fixed to the frame 11 and the piston rod 62 is used as the moving portion. However, in this invention, the piston rod is used as the frame. It may be fixed and the cylinder body may be used as the moving portion. Further, in the above-mentioned embodiment, the pair of lock bodies 74 and 75 are moved by the pair of cylinders 81 and 82. However, in the present invention, the driving force of one cylinder, motor or the like is cammed. Alternatively, they may be transmitted to the pair of lock bodies by links or the like, and these lock bodies may be moved in synchronization.

[0020]

[Effect of the device]

 As described above, according to this invention, the moving distance of the lock block is shortened, so that the work efficiency is improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

FIG. 2 is a front sectional view in the vicinity of an opening / closing and mold clamping cylinder.

3 is a cross-sectional view taken along the line II of FIG.

FIG. 4 is a sectional view of a cushion body.

FIG. 5 is a partially cutaway front view showing an example of a conventional mold clamping device when a mold is opened.

FIG. 6 is a partially cutaway front view similar to FIG. 5 when the mold is closed.

[Explanation of symbols]

31 ... frame 36 ... one mold 38 ... connecting rod 39 ... die plate 40 ... other mold 45 ... moving plate 48 ... opening / closing cylinder 58 ... mold clamping cylinder 62 ... moving part 63 ... holes 74, 75 ... lock body 76 … Lock blocks 81,82… Cylinders 87,88… Rollers 89… Moving means 91,92,93,94… Cushion bodies H… Closed position R… Separated position

Claims (4)

[Scope of utility model registration request] 1. A movable die plate having a frame, one die fixed to the frame, another die supported by the frame and forming a pair with the one die, and a die plate connected to the movable die plate. By moving the moving plate connected via the rod, the moving plate attached to the frame, the connecting rod, the die plate, and the other mold integrally, the other mold is moved closer to or separated from the one mold. An opening / closing cylinder that opens and closes the mold; a mold clamping cylinder that is mounted between the frame and the moving plate and that is mounted on the frame and whose moving part can be inserted into the hole formed in the moving plate; A lock block that can move while sliding in contact with the surface of the moving plate that faces the cylinder, and a lock block that closes the hole and separates the lock block from the hole. A mold clamping device of an injection molding machine, comprising: a moving unit that moves between the lock blocks, the lock blocks being close to each other when in the closed position, and the lock blocks located on both sides of the hole when in the separated position. 2. The mold clamping device for an injection molding machine, comprising the lock body according to claim 1, wherein the lock means is moved toward and away from each other by the moving means. 2. The moving means is arranged on both sides of the hole, and the lock bodies are connected to each other. When the moving portion of the mold clamping cylinder is inserted into the hole, both the lock bodies are applied to both sides of the moving portion. A pair of cylinders for urging the lock bodies in the contacting state to approach each other and for urging the lock bodies in a direction separating from each other when the lock bodies in the closed position are pressed against the moving plate by the moving portion. The mold clamping device for an injection molding machine according to claim 1, comprising: 3. The mold clamping device for an injection molding machine according to claim 2, wherein a roller capable of rolling contact with the moving portion is rotatably supported at a tip end portion of each lock body which is close to the moving portion. 4. The moving plate is provided with a cushion body that can be brought into contact with the lock body when the lock body moves near the closed position and the separated position, respectively, and the lock bodies stop at the closed position and the separated position by the cushion bodies. The mold clamping device for an injection molding machine according to claim 1, wherein an impact at the time of performing is alleviated.