Mold core-pulling mechanism and injection mold

Abstract

The embodiment of the utility model provides a mold core pulling mechanism and an injection mold, and relates to the technical field of molds. The mold core-pulling mechanism comprises a core-pulling assembly, a hydraulic loop and a one-way valve capable of being controlled to be conducted reversely. The core pulling assembly comprises a hydraulic oil cylinder and an insert pin, the hydraulic oil cylinder comprises a cylinder body, a piston and a telescopic rod, the piston is arranged in the cylinder body in a sliding mode, a rodless cavity and a rod cavity are divided in the cylinder body, the telescopic rod is connected with the piston and extends out of the cylinder body through the rod cavity, and the insert pin is fixed to the telescopic rod; the hydraulic loop comprises a first oil way communicating with the rodless cavity and a second oil way communicating with the rod cavity. The one-way valve is arranged on the first oil way, and the forward conduction direction of the one-way valve faces the hydraulic oil cylinder. The mold core-pulling mechanism provided by the embodiment of the utility model is simple in structure and relatively small in occupied space, the strength of the injection mold cannot be influenced, and the mold core-pulling mechanism can be suitable for more types of injection molds.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of molds, in particular to a mold core pulling mechanism and an injection mold. BACKGROUND

[0002] An injection mold generally uses a pin to form a hole or a channel on a molded product, and before the injection mold is opened, a core pulling mechanism is used to pull the pin out of the hole or the channel on the molded product. In the related art, some holes or channels on the molded product extend obliquely, and the pin also needs to move obliquely. A core pulling mechanism driven by a hydraulic cylinder generally has a slider with a T-shaped sliding groove. The slider is connected to the telescopic rod of the hydraulic cylinder, and the pin is in sliding fit with the T-shaped sliding groove. During the core pulling process, the telescopic rod drives the slider to move horizontally, so that the pin slides obliquely along the T-shaped sliding groove, thereby pulling the pin out of the hole or the channel on the molded product.

[0003] However, such a core pulling mechanism occupies a large space, which will affect the strength of the injection mold to some extent. In addition, for an injection mold with a hot nozzle, the position of the core pulling mechanism also needs to avoid the hot nozzle. However, due to the large space occupied by the core pulling mechanism, after avoiding the hot nozzle, there is not enough space to accommodate the core pulling mechanism. Therefore, such a core pulling mechanism is difficult to meet the use requirements of various injection molds. CONTENT OF THE UTILITY MODEL

[0004] Therefore, an embodiment of the present application aims to provide a mold core pulling mechanism and an injection mold which have a simple structure and occupy a relatively small space.

[0005] To achieve the above-mentioned purpose, an embodiment of the present application provides a mold core pulling mechanism, comprising:

[0006] a core pulling assembly, the core pulling assembly comprising a hydraulic cylinder and a pin, the hydraulic cylinder comprising a cylinder body, a piston and a telescopic rod, the piston being slidably arranged in the cylinder body and separating a rodless cavity and a rod cavity in the cylinder body, the telescopic rod being connected to the piston and extending out of the cylinder body through the rod cavity, the pin being fixed to the telescopic rod;

[0007] a hydraulic circuit, the hydraulic circuit comprising a first oil path in communication with the rodless cavity and a second oil path in communication with the rod cavity;

[0008] a controllable reverse conduction one-way valve, the one-way valve being arranged in the first oil path, and the forward conduction direction of the one-way valve being towards the hydraulic cylinder.

[0009] In one embodiment, the one-way valve is a valve having a forward oil inlet, a forward oil outlet, and a control oil port, the hydraulic circuit includes a pilot oil passage, the forward oil outlet is in communication with the rodless chamber, and the pilot oil passage is in communication with the control oil port for enabling controlled reverse conduction of the one-way valve.

[0010] In one embodiment, the pilot oil passage is in communication with the second oil passage.

[0011] In one embodiment, the one-way valve is an electrically controlled one-way valve.

[0012] In one embodiment, the number of core pulling assemblies is plural, the first oil passage includes a first main oil passage and first sub-oil passages corresponding to the core pulling assemblies one by one, each of the first sub-oil passages is in parallel with each other, and each of the first sub-oil passages is in communication with the rodless chamber of the hydraulic cylinder of the corresponding core pulling assembly, the first main oil passage is in communication with each of the first sub-oil passages, and the one-way valve is arranged in the first main oil passage.

[0013] In one embodiment, the number of core pulling assemblies is plural, the second oil passage includes a second main oil passage and second sub-oil passages corresponding to the core pulling assemblies one by one, each of the second sub-oil passages is in parallel with each other, and each of the second sub-oil passages is in communication with the rod chamber of the hydraulic cylinder of the corresponding core pulling assembly, and the second main oil passage is in communication with each of the second sub-oil passages.

[0014] In one embodiment, the core pulling assembly further includes an adapter rod, the adapter rod is detachably connected with the telescopic rod and the insert pin respectively.

[0015] In one embodiment, the adapter rod is inserted into the telescopic rod, and the adapter rod is rotationally stopped with the telescopic rod.

[0016] In one embodiment, the adapter rod is clamped with the insert pin.

[0017] In one embodiment, the core pulling assembly further includes a rotation stopping block.

[0018] Part of the outer side wall of the telescopic rod forms a rotation stopping surface, the rotation stopping block is located on the circumferential side of the adapter rod and protrudes from one end of the adapter rod close to the telescopic rod, the rotation stopping block and the rotation stopping surface face each other and form a mutual stop constraint in the rotation direction of the adapter rod.

[0019] In one embodiment, part of the outer side wall of the adapter rod forms a rotation stopping surface, the rotation stopping block is located on the circumferential side of the telescopic rod and protrudes from one end of the telescopic rod close to the adapter rod, the rotation stopping block and the rotation stopping surface face each other and form a mutual stop constraint in the rotation direction of the adapter rod.

[0020] In one embodiment, the insert needle comprises a needle body and a clamping block arranged at one end of the needle body, the clamping block protruding from the outer wall of the needle body; the adapter rod has a clamping groove and an avoiding groove at one end close to the insert needle, the clamping groove and the avoiding groove are in communication, and a step surface is formed on the side of the communication position towards the clamping groove; the clamping groove has a first opening, the avoiding groove has a second opening and a third opening, the first opening and the second opening are located on the outer wall of the adapter rod, and the third opening is located on the side of the avoiding groove away from the clamping groove, the third opening avoids the needle body, the clamping block is clamped into the clamping groove through the first opening, and a part of the needle body enters the avoiding groove through the second opening.

[0021] In one embodiment, the mold core pulling mechanism further comprises a guide sleeve, the insert needle is arranged in the guide sleeve and can slide relative to the guide sleeve.

[0022] In one embodiment, the outer wall of the guide sleeve has a recessed cooling groove.

[0023] Another embodiment of the present application provides an injection mold, comprising:

[0024] a first mold body;

[0025] a second mold body, the second mold body is detachably connected with the first mold body to form a cavity;

[0026] The mold core pulling mechanism described above is arranged in the first mold body, and the retractable rod is extended to make the insert needle extend into the cavity.

[0027] In one embodiment, the mold core pulling mechanism further comprises a guide sleeve, the insert needle is arranged in the guide sleeve and can slide relative to the guide sleeve; the outer surface of the guide sleeve has a recessed cooling groove, the first mold body has a cooling flow channel, the guide sleeve is fixed to the first mold body, the guide sleeve and the first mold body are sealed to seal and close the cooling groove, and the cooling flow channel is in communication with the cooling groove.

[0028] The mold core pulling mechanism and the injection mold provided by the embodiment of the present application are characterized in that a one-way valve capable of being reversely conducted under control is arranged on the first oil path of the hydraulic circuit, and the forward conducting direction of the one-way valve is toward the hydraulic cylinder. Since the first oil path is in communication with the rodless cavity of the hydraulic cylinder, and the telescopic rod of the hydraulic cylinder is extended under the action of the hydraulic oil in the rodless cavity, when the one-way valve is forward conducted, the hydraulic oil can flow into the rodless cavity to make the telescopic rod extend, and since the hydraulic oil cannot flow reversely along the first oil path under the prevention of the one-way valve, the hydraulic oil cannot flow out of the rodless cavity, so that the telescopic rod can be stably extended under the action of the hydraulic oil in the rodless cavity and cannot be retracted, thereby ensuring that the insert pin can also be substantially kept stationary during the injection molding process and cannot be retracted due to the retraction of the telescopic rod. The mold core pulling mechanism provided by the embodiment of the present application is simple in structure and relatively small in occupied space, and can neither affect the strength of the injection mold nor be applied to more types of injection molds. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 A structure schematic view of an injection mold and a molded product provided by the embodiment of the present application is shown in the figure, in which the one-way valve is omitted;

[0030] Figure 2 A structure schematic view of the mold core pulling mechanism shown in Figure 1 is shown in the figure, in which the one-way valve is omitted;

[0031] Figure 3 A structure schematic view of the molded product shown in Figure 1 is shown in the figure;

[0032] Figure 4 A hydraulic principle view of the mold core pulling mechanism shown in Figure 1 is shown in the figure, in which the dashed arrow represents the flow direction of the hydraulic oil when the one-way valve is forward conducted;

[0033] Figure 5 A schematic view of the core pulling assembly shown in Figure 1 in the injection molding process to form a screw hole of the molded product;

[0034] Figure 6 A structure schematic view of the core pulling assembly shown in Figure 1 is shown in the figure;

[0035] Figure 7 An exploded view of the core pulling assembly shown in Figure 6 is shown in the figure;

[0036] Figure 8 A sectional view of the core pulling assembly shown in Figure 6 is shown in the figure;

[0037] Figure 9 A partial enlarged view of position A in Figure 8 is shown in the figure;

[0038] Figure 10 B-B sectional view of the adapter rod shown in FIG. 1A; Figure 8

[0039] Figure 11 structure diagram of the adapter rod shown in FIG. 1A; Figure 6

[0040] Figure 12 structure diagram of the guide sleeve shown in FIG. 1A. Figure 1

[0041] Legend of reference signs:

[0042] 100, injection mold; 10, mold core pulling mechanism; 11, core pulling assembly; 111, hydraulic oil cylinder; 1111, cylinder body; 1111a, rodless cavity; 1111b, rod cavity; 1112, piston; 1113, telescopic rod; 1113a, plug-in hole; 1113b, rotation-stopping mating surface; 112, pin; 1121, pin body; 1122, clamping block; 113, adapter rod; 113a, plug-in column; 113b, clamping groove; 113b1, first opening; 113c, avoiding groove; 113c1, second opening; 113c2, third opening; 113d, step surface; 114, rotation-stopping block; 12, hydraulic circuit; 121, first oil way; 1211, first main oil way; Z1, first oil way group; 1212, first sub-oil way; 1213, first connecting oil way; 122, second oil way; 1221, second main oil way; Z2, second oil way group; 1222, second sub-oil way; 1223, second connecting oil way; 123, pilot oil way; 13, one-way valve; 13a, forward oil inlet; 13b, forward oil outlet; 13c, control oil port; 14, switching valve; 15, guide sleeve; 15a, cooling groove; 200, formed product; 200a, screw hole. DETAILED DESCRIPTION

[0043] In the description of the embodiments of the present application, it should be noted that the terms “telescopic direction”, “vertical direction” are based on the orientation or positional relationship shown in the drawings. These orientation terms are only for the convenience of describing the embodiments of the present application and simplifying the description, and are not intended to indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. Figure 5

[0044] The embodiments of the present application provide an injection mold 100, please refer to Figure 1 and Figure 2 The injection mold 100 includes a first mold body (not shown in the figure), a second mold body (not shown in the figure) and a mold core pulling mechanism 10.

[0045] ​​​​The second mold body is detachably butted against the first mold body to form a cavity. A molded product 200 can be manufactured by injecting a molding material into the cavity.

[0046] Referring to Figure 2 , Figures 4 to 8 The mold core pulling mechanism 10 of the embodiment includes a core pulling assembly 11, a hydraulic circuit 12, and a one-way valve 13.

[0047] The core pulling assembly 11 includes a hydraulic cylinder 111 and a pin 112. The hydraulic cylinder 111 includes a cylinder body 1111, a piston 1112, and a telescopic rod 1113. The piston 1112 is slidably arranged in the cylinder body 1111, and divides the cylinder body 1111 into a rodless cavity 1111a and a rod cavity 1111b. The telescopic rod 1113 is connected with the piston 1112 and extends out of the cylinder body 1111 through the rod cavity 1111b. The pin 112 is fixed to the telescopic rod 1113. The hydraulic circuit 12 includes a first oil passage 121 communicating with the rodless cavity 1111a and a second oil passage 122 communicating with the rod cavity 1111b.

[0048] Specifically, the first oil passage 121 is a passage through which hydraulic oil flows into and out of the rodless cavity 1111a, and the second oil passage 122 is a passage through which hydraulic oil flows into and out of the rod cavity 1111b.

[0049] When hydraulic oil flows into the rodless cavity 1111a through the first oil passage 121 (i.e., the first oil passage 121 is oil-in), the hydraulic oil in the rodless cavity 1111a drives the piston 1112 to move, and the piston 1112 extrudes the hydraulic oil in the rod cavity 1111b, so that the hydraulic oil in the rod cavity 1111b flows out through the second oil passage 122 (i.e., the second oil passage 122 is oil-out), and at the same time, the telescopic rod 1113 is driven by the piston 1112 to move out of the cylinder body 1111, so that the telescopic rod 1113 extends relative to the cylinder body 1111. When hydraulic oil flows into the rod cavity 1111b through the second oil passage 122 (i.e., the second oil passage 122 is oil-in), the hydraulic oil in the rod cavity 1111b drives the piston 1112 to move, and the piston 1112 extrudes the hydraulic oil in the rodless cavity 1111a, so that the hydraulic oil in the rodless cavity 1111a flows out through the first oil passage 121 (i.e., the first oil passage 121 is oil-out), and at the same time, the telescopic rod 1113 is driven by the piston 1112 to move into the cylinder body 1111, so that the telescopic rod 1113 retracts relative to the cylinder body 1111. That is, the telescopic rod 1113 can be extended and retracted under the action of hydraulic oil.

[0050] Referring to Figure 4The mold core-pulling mechanism 10 includes a switching valve 14 provided in the hydraulic circuit 12, and the switching valve 14 is switched to achieve the oil inlet and outlet switching of the first oil passage 121 and the second oil passage 122.

[0051] Please continue to refer to Figures 2 to 5 The insert pin 112 is used to form a hole, a channel or the like structure (such as a screw hole 200a shown in Figure 3 and Figure 5 ) on the formed product 200, and the insert pin 112 is fixed to the telescopic rod 1113 to be telescoped with the telescopic rod 1113.

[0052] The way in which the insert pin 112 is fixed to the telescopic rod 1113 is not limited, but in order to facilitate the installation of the insert pin 112, exemplary, please refer to Figure 2 , Figures 5 to 8 The core-pulling assembly 11 can include an adapter rod 113, which is detachably connected with the telescopic rod 1113 and the insert pin 112. That is, the insert pin 112 can be connected with the telescopic rod 1113 through the adapter rod 113, so that the insert pin 112 can be fixed to the telescopic rod 1113 without changing the structure of the telescopic rod 1113 and / or the insert pin 112.

[0053] The way in which the adapter rod 113 is detachably connected with the telescopic rod 1113 is not limited, exemplary, please refer to Figures 6 to 8 The adapter rod 113 is inserted with the telescopic rod 1113, and the adapter rod 113 is rotationally stopped with the telescopic rod 1113, that is, the adapter rod 113 and the telescopic rod 1113 can be connected by insertion, and the adapter rod 113 will not rotate relative to the telescopic rod 1113.

[0054] Figure 7 The telescopic rod 1113 has an insertion hole 1113a, and the adapter rod 113 has an insertion column 113a inserted into the insertion hole 1113a to achieve the insertion of the adapter rod 113 and the telescopic rod 1113. In other ways, the telescopic rod 1113 can have an insertion column 113a, and the adapter rod 113 can have an insertion hole 1113a.

[0055] The way in which the adapter rod 113 is rotationally stopped with the telescopic rod 1113 is also not limited, exemplary, please refer to Figures 7 to 10 Part of the outer wall of the telescopic rod 1113 can form a rotationally stopping surface 1113b, and the core-pulling assembly 11 can further include a rotationally stopping block 114 which can be connected with the adapter rod 113. Figures 7 to 10The rotation stopper 114 is fastened to the adapter rod 113 by a fastener such as a screw, and in other embodiments, the rotation stopper 114 can be connected to the adapter rod 113 by welding or the like. The rotation stopper 114 is located on the circumferential side of the adapter rod 113 and protrudes from the end of the adapter rod 113 close to the telescopic rod 1113. The rotation stopper 114 and the rotation stopper matching surface 1113b face each other and form a mutual stop constraint in the rotation direction of the adapter rod 113. That is, after the rotation stopper 114 and the rotation stopper matching surface 1113b are arranged, if the adapter rod 113 has a tendency to rotate relative to the telescopic rod 1113, the rotation stopper matching surface 1113b or the outer edge of the rotation stopper matching surface 1113b along the circumferential direction of the telescopic rod 1113 will abut against the rotation stopper 114, thereby preventing the rotation of the adapter rod 113.

[0056] Figures 7 to 10 The shown core pulling assembly 11 is provided with two rotation stoppers 114, which are located on opposite sides of the same cross section of the adapter rod 113, and the rotation stopper matching surface 1113b of the telescopic rod 1113 corresponds to the rotation stopper 114 one by one, so that the rotation of the adapter rod 113 can be better prevented. In other embodiments, there can be only one rotation stopper 114.

[0057] In other embodiments, part of the outer side wall of the adapter rod 113 can form the rotation stopper matching surface 1113b, and the rotation stopper 114 is located on the circumferential side of the telescopic rod 1113 (i.e., the rotation stopper 114 is connected to the telescopic rod 1113) and protrudes from the end of the telescopic rod 1113 close to the adapter rod 113. The rotation stopper 114 and the rotation stopper matching surface 1113b face each other and form a mutual stop constraint in the rotation direction of the adapter rod 113.

[0058] The adapter rod 113 and the dowel pin 112 are not limited in the way of being connected, and exemplary, please refer to Figure 7 、 Figure 8 and Figure 11The inlay needle 112 includes a needle body 1121 and a clamping block 1122 arranged at one end of the needle body 1121, and the clamping block 1122 protrudes from the outer side wall of the needle body 1121. The adapter rod 113 has a clamping groove 113b and an avoiding groove 113c located on the side of the clamping groove 113b away from the telescopic rod 1113. The clamping groove 113b and the avoiding groove 113c are communicated, and a step surface 113d facing the clamping groove 113b is formed on the side of the communication. The clamping groove 113b has a first opening 113b1, the avoiding groove 113c has a second opening 113c1 and a third opening 113c2, the first opening 113b1 and the second opening 113c1 are located on the outer side wall of the adapter rod 113, and the third opening 113c2 is located on the side of the avoiding groove 113c away from the clamping groove 113b. The third opening 113c2 passes through the avoiding needle body 1121, so that the clamping block 1122 is clamped into the clamping groove 113b through the first opening 113b1, and a part of the needle body 1121 enters the avoiding groove 113c through the second opening 113c1.

[0059] That is, the clamping block 1122 of the inlay needle 112 is clamped into the clamping groove 113b from the side of the adapter rod 113, so that the adapter rod 113 and the inlay needle 112 are clamped, and the step surface 113d can stop the clamping block 1122 in the clamping groove 113b, so that the clamping block 1122 can be limited in the axial direction of the inlay needle 112.

[0060] In other embodiments, the core pulling assembly 11 can also not be provided with the adapter rod 113, for example, the inlay needle 112 can be directly connected with the telescopic rod 1113.

[0061] Please continue to refer to Figure 4 The one-way valve 13 is a valve that automatically opens and closes relying on the pressure of the fluid itself, and its core function is to allow the fluid to flow in a predetermined single direction and forcibly prevent the fluid from flowing in the opposite direction.

[0062] The one-way valve 13 described in the embodiments of the present application can be normally open and can be reversely open under control. In the normally open state of the one-way valve 13, the fluid can flow in the normally open direction without the action of manual or external force, but the fluid cannot flow in the opposite direction. The normally open is the most basic function of the one-way valve 13.

[0063] The reversely open under control means that the one-way valve 13 can be reversely open by relying on the action of external force. In the reversely open state of the one-way valve 13, the fluid can flow in the opposite direction (i.e., the flow direction of the fluid is opposite to the normally open direction).

[0064] Please refer to Figure 4A one-way valve 13 is located in the first oil passage 121, and the forward direction of the one-way valve 13 faces the hydraulic cylinder 111. That is, before the one-way valve 13 is controlled to reverse, the hydraulic oil can flow into the rodless chamber 1111a along the first oil passage 121 by its own pressure, but the hydraulic oil cannot flow in the reverse direction. Since the hydraulic oil cannot flow in the reverse direction, the hydraulic oil entering the rodless chamber 1111a cannot flow out of the rodless chamber 1111a. The hydraulic oil in the rodless chamber 1111a can resist the piston 1112, so that the piston 1112 can remain basically stationary relative to the cylinder 1111, thereby preventing the telescopic rod 1113 from retracting relative to the cylinder 1111.

[0065] When the telescopic rod 1113 needs to retract, by controlling the one-way valve 13 to reverse the flow, the hydraulic oil can flow in the reverse direction along the first oil passage 121, so that the hydraulic oil in the rodless chamber 1111a can flow out from the rodless chamber 1111a. Thus, the hydraulic oil entering the rod chamber 1111b from the second oil passage 122 can push the piston 1112 to move, and the telescopic rod 1113 can retract under the action of the piston 1112.

[0066] The mold core-pulling mechanism 10 is set on the first mold body. The telescopic rod 1113 extends out, allowing the insert pin 112 to extend into the cavity formed by the first mold body and the second mold body.

[0067] by Figure 1 , Figure 3 and Figure 5 Taking the molded product 200 as an example, the molded product 200 has a screw hole 200a. In the injection molding state, the center line of the screw hole 200a is inclined relative to the vertical direction, that is, the screw hole 200a extends obliquely. The insert pin 112 is used to construct the screw hole 200a. Since the screw hole 200a extends obliquely, the extension and retraction direction of the telescopic rod 1113 is also inclined relative to the vertical direction.

[0068] The injection molding process of the molded product 200 mainly includes the following steps: 1. Mold closing (i.e., the first mold body and the second mold body are joined to form a cavity); 2. Controlling hydraulic oil to flow from the first oil passage 121 into the rodless cavity 1111a, the telescopic rod 1113 extends to drive the insert pin 112 into the cavity; 3. Injection molding; 4. After injection molding is completed, controlling the one-way valve 13 to reverse the flow and controlling hydraulic oil to flow from the second oil passage 122 into the rod cavity 1111b, the telescopic rod 1113 retracts to drive the insert pin 112 out of the screw hole 200a (this step is also called core pulling); 5. Mold opening (i.e., the first mold body and the second mold body are separated); 6. Ejecting the molded product 200.

[0069] That is, during the injection molding process, the telescopic rod 1113 remains in the extended state, and after the injection molding is completed, the telescopic rod 1113 is retracted to drive the pin 112 to retreat, so that the pin 112 is extracted from the screw hole 200a on the molded product 200.

[0070] In the related art, for a molded product having a hole, a channel or the like structure extending obliquely, the pin also needs to move obliquely correspondingly, but during the injection molding process, the pin needs to remain stationary and cannot retreat, otherwise it will cause the molded product to have steps, differences and the like defects. In order to ensure that the pin does not retreat during the injection molding process, some core pulling mechanisms driven by hydraulic cylinders generally have a slider with a T-shaped sliding groove, the slider is connected with the telescopic rod of the hydraulic cylinder, the pin is in sliding fit with the T-shaped sliding groove, during the injection molding process, the pin remains stationary by abutting against the slider, during the core pulling process, the telescopic rod drives the slider to move in the horizontal direction, so that the pin slides obliquely along the T-shaped sliding groove, thereby extracting the pin from the hole, the channel or the like on the molded product. However, such a core pulling mechanism occupies a large space, which will affect the strength of the injection mold to some extent, in addition, for an injection mold having a hot nozzle, the setting position of the core pulling mechanism also needs to avoid the hot nozzle, and due to the large space occupied by the core pulling mechanism, after avoiding the hot nozzle, there is not enough space to accommodate the core pulling mechanism, therefore, such a core pulling mechanism is also difficult to meet the use requirements of various injection molds. Although some core pulling mechanisms use self-locking cylinders with self-locking function to prevent the pin from retreating during the injection molding process, the price of the self-locking cylinder is relatively high, and if the self-locking cylinder is used, the production cost of the injection mold will be greatly increased.

[0071] The mold core pulling mechanism 10 of the embodiment of the present application is provided with a one-way valve 13 capable of controlled reverse conduction on the first oil path 121 of the hydraulic circuit 12, and the positive conduction direction of the one-way valve 13 is towards the hydraulic oil cylinder 111. Since the first oil path 121 is in communication with the rodless cavity 1111a of the hydraulic oil cylinder 111, and the telescopic rod 1113 of the hydraulic oil cylinder 111 is extended under the action of the hydraulic oil in the rodless cavity 1111a, when the one-way valve 13 is positively conducted, the hydraulic oil can flow into the rodless cavity 1111a to make the telescopic rod 1113 extend, and since the hydraulic oil cannot flow reversely along the first oil path 121 due to the blocking of the one-way valve 13, the hydraulic oil cannot flow out of the rodless cavity 1111a, so the telescopic rod 1113 can stably extend under the action of the hydraulic oil in the rodless cavity 1111a and will not retract, thereby ensuring that the insert pin 112 can also be kept substantially stationary during the injection molding process and will not be retracted due to the retraction of the telescopic rod 1113. Compared with the core pulling mechanism with a slider in the related art, the mold core pulling mechanism 10 of the embodiment of the present application has a simple structure and occupies relatively less space, which will not affect the strength of the injection mold 100 and can be applied to more types of injection molds 100. In addition, since the mold core pulling mechanism 10 of the embodiment of the present application uses the one-way valve 13 to prevent the insert pin 112 from retracting during the injection molding process, the hydraulic oil cylinder 111 of the mold core pulling mechanism 10 can use a cylinder without self-locking function, and compared with the core pulling mechanism using a self-locking cylinder in the related art, the production cost of the mold core pulling mechanism 10 of the embodiment of the present application is also relatively low.

[0072] In addition, it should be noted that the mold core pulling mechanism 10 of the embodiment of the present application is not limited to forming the hole, channel and other structures extending obliquely on the molded product 200, and the mold core pulling mechanism 10 of the embodiment of the present application can also be used for holes, channels and other structures extending in other directions such as horizontal direction and vertical direction.

[0073] Please continue to refer to Figure 1 and Figure 2 For the molded product 200 which needs to use the core pulling assembly 11 to form more than one hole, channel and other structures, the number of core pulling assemblies 11 can also be multiple, and each core pulling assembly 11 is used to form a corresponding hole, channel. For example, Figure 3 The molded product 200 shown in the figure has four screw holes 200a, and all of the four screw holes 200a need to be formed by using the core pulling assembly 11, so the mold core pulling mechanism 10 is also provided with four core pulling assemblies 11, and the core pulling assemblies 11 correspond one by one to the screw holes 200a.

[0074] Please refer to Figure 1 and Figure 2For the mold core pulling mechanism 10 with multiple core pulling assemblies 11, the first oil path 121 may, for example, include a first main oil path 1211 and a first sub-oil path 1212 corresponding to each core pulling assembly 11, each first sub-oil path 1212 is parallel to each other, and each first sub-oil path 1212 is in communication with the rodless cavity 1111a of the hydraulic cylinder 111 of the corresponding core pulling assembly 11, and the first main oil path 1211 is in communication with each first sub-oil path 1212. That is, when the oil is in, the hydraulic oil flows from the first main oil path 1211 into each first sub-oil path 1212, and then flows into the rodless cavity 1111a of the corresponding hydraulic cylinder 111 through each first sub-oil path 1212, and when the oil is returned, the hydraulic oil flowing out of the rodless cavity 1111a of each hydraulic cylinder 111 flows into the first main oil path 1211 through the corresponding first sub-oil path 1212, thereby, when the oil is in, the hydraulic oil can flow into the rodless cavity 1111a of the corresponding hydraulic cylinder 111 along each first sub-oil path 1212, and when the oil is returned, the hydraulic oil in the rodless cavity 1111a of each hydraulic cylinder 111 can also flow out of the rodless cavity 1111a, thereby improving the delivery efficiency of the hydraulic oil.

[0075] Please refer to Figure 1 and Figure 2 When the number of core pulling assemblies 11 is at least four, the first sub-oil path 1212 corresponding to the hydraulic cylinder 111 can be divided into at least two first oil path groups Z1, each first oil path group Z1 has at least two first sub-oil paths 1212, and the first oil path 121 further includes a first connecting oil path 1213 corresponding to each first oil path group Z1, each first connecting oil path 1213 is parallel to each other, and each first connecting oil path 1213 is in communication with each first sub-oil path 1212 in the corresponding first oil path group Z1, and the first main oil path 1211 is in communication with each first connecting oil path 1213, for example, Figure 1 and Figure 2The hydraulic circuit 12 of the mold core-pulling mechanism 10 shown has four first sub-oil paths 1212, which are divided into two first oil path groups Z1, each first oil path group Z1 having two first sub-oil paths 1212, and the first connecting oil paths 1213 are also two, which are connected in parallel, one first connecting oil path 1213 is respectively communicated with the two first sub-oil paths 1212 in one of the first oil path groups Z1, and the other first connecting oil path 1213 is respectively communicated with the two first sub-oil paths 1212 in the other of the first oil path groups Z1, and the first main oil path 1211 is respectively communicated with the two first connecting oil paths 1213. That is, when the oil is fed, the hydraulic oil first flows into each first connecting oil path 1213 from the first main oil path 1211, and then flows into each first sub-oil path 1212 in the corresponding first oil path group Z1 through each first connecting oil path 1213, and when the oil is returned, the hydraulic oil in each first sub-oil path 1212 in the same first oil path group Z1 flows into the same first connecting oil path 1213, and the hydraulic oil flowing into each first connecting oil path 1213 then flows into the first main oil path 1211, respectively. This arrangement can not only facilitate the arrangement of the oil path, but also improve the efficiency of the hydraulic oil delivery.

[0076] Further, since the hydraulic oil flows into each first sub-oil path 1212 from the first main oil path 1211 when the oil is fed, the one-way valve 13 can be arranged in the first main oil path 1211, so that only one one-way valve 13 is needed to make the extension rods 1113 of all the hydraulic oil cylinders 111 remain stable during the injection molding process, thereby saving the number of one-way valves 13 and reducing the production cost.

[0077] In other embodiments, a one-way valve 13 can also be arranged in each first sub-oil path 1212, i.e. the one-way valve 13 corresponds to the core-pulling assembly 11 one by one, and for the mold core-pulling mechanism 10 with the first connecting oil path 1213 of the hydraulic circuit 12, a one-way valve 13 can also be arranged in each first connecting oil path 1213, i.e. the one-way valve 13 corresponds to the first oil path group Z1 one by one.

[0078] Similarly, please refer to Figure 1 and Figure 2For the core-pulling mechanism 10 with multiple core-pulling assemblies 11, the second oil passage 122 can also include a second main oil passage 1221 and a second sub-oil passage 1222 corresponding to each core-pulling assembly 11, each second sub-oil passage 1222 is parallel to each other, and each second sub-oil passage 1222 is in communication with the rod cavity 1111b of the hydraulic cylinder 111 of the corresponding core-pulling assembly 11, and the second main oil passage 1221 is in communication with each second sub-oil passage 1222. That is, when the oil is in, the hydraulic oil flows from the second main oil passage 1221 into each second sub-oil passage 1222, and then flows into the rod cavity 1111b of the corresponding hydraulic cylinder 111 through each second sub-oil passage 1222. When the oil is returned, the hydraulic oil flowing out of the rod cavity 1111b of each hydraulic cylinder 111 flows into the second main oil passage 1221 through the corresponding second sub-oil passage 1222. Thus, when the oil is in, the hydraulic oil can flow into the rod cavity 1111b of the corresponding hydraulic cylinder 111 along each second sub-oil passage 1222 at approximately the same time, and when the oil is returned, the hydraulic oil in the rod cavity 1111b of each hydraulic cylinder 111 can also flow out of the rod cavity 1111b at approximately the same time, thereby improving the delivery efficiency of the hydraulic oil.

[0079] Please refer to Figure 1 and Figure 2 When the number of core-pulling assemblies 11 is at least four, the second sub-oil passage 1222 corresponding to the hydraulic cylinder 111 can be divided into at least two second oil passage groups Z2, each second oil passage group Z2 has at least two second sub-oil passages 1222, and the second oil passage 122 also includes a second connecting oil passage 1223 corresponding to each second oil passage group Z2, each second connecting oil passage 1223 is parallel to each other, and each second connecting oil passage 1223 is in communication with each second sub-oil passage 1222 in the corresponding second oil passage group Z2, and the second main oil passage 1221 is in communication with each second connecting oil passage 1223, for example, Figure 1 and Figure 2The hydraulic circuit 12 of the mold core-pulling mechanism 10 shown has four second sub-oil paths 1222, which are divided into two second oil path groups Z2, each second oil path group Z2 having two second sub-oil paths 1222, and the second connecting oil paths 1223 are also two, which are connected in parallel, one second connecting oil path 1223 is respectively communicated with the two second sub-oil paths 1222 in one of the second oil path groups Z2, and the other second connecting oil path 1223 is respectively communicated with the two second sub-oil paths 1222 in the other of the second oil path groups Z2, and the second main oil path 1221 is respectively communicated with the two second connecting oil paths 1223. That is, when the oil is fed, the hydraulic oil first flows into each second connecting oil path 1223 from the second main oil path 1221, and then flows into each second sub-oil path 1222 in the corresponding second oil path group Z2 through each second connecting oil path 1223, and when the oil is returned, the hydraulic oil in each second sub-oil path 1222 in the same second oil path group Z2 flows into the same second connecting oil path 1223, and the hydraulic oil flowing into each second connecting oil path 1223 then flows into the second main oil path 1221, respectively. This arrangement can not only facilitate the arrangement of the oil path, but also improve the efficiency of the hydraulic oil delivery.

[0080] In some embodiments, referring to Figure 4 , the one-way valve 13 can have a positive oil inlet 13a, a positive oil outlet 13b and a control oil port 13c, and the hydraulic circuit 12 includes a pilot oil path 123, the positive oil outlet 13b is communicated with the rodless cavity 1111a, and the pilot oil path 123 is communicated with the control oil port 13c for realizing the controlled reverse conduction of the one-way valve 13. That is, the one-way valve 13 can realize reverse conduction under the action of the hydraulic oil, and such one-way valve 13 can also be called a hydraulic control one-way valve.

[0081] Specifically, the positive oil inlet 13a is the inlet of the one-way valve 13 when the one-way valve 13 is positively conducted, and the positive oil outlet 13b is the outlet of the one-way valve 13 when the one-way valve 13 is positively conducted. The positive oil outlet 13b is communicated with the rodless cavity 1111a, which means that after the hydraulic oil flows out of the positive oil outlet 13b, it flows into the rodless cavity 1111a along the first oil path 121.

[0082] The pilot oil passage 123 is a passage for hydraulic oil to flow to the control oil port 13c. In the case where the one-way valve 13 is in the normally open state, hydraulic oil does not flow to the control oil port 13c through the pilot oil passage 123. When the one-way valve 13 needs to be reversely opened, hydraulic oil flows to the control oil port 13c through the pilot oil passage 123, and then flows into the one-way valve 13 through the control oil port 13c. The hydraulic oil moves by pushing the moving component in the one-way valve 13, so as to push open the valve core in the one-way valve 13. After the valve core is pushed open, hydraulic oil can flow into the one-way valve 13 from the normal oil outlet port 13b, and then flow out from the normal oil inlet port 13a, so as to reversely open the one-way valve 13.

[0083] It should be noted that the one-way valve 13 in the embodiment can be any one-way valve capable of reversely opening in the related art. Since the improvement of the specific structure of the one-way valve 13 is not involved, the specific structure of the one-way valve 13 is not described herein.

[0084] Since the mold core pulling mechanism 10 in the embodiment is provided with the hydraulic circuit 12, the one-way valve 13 reversely opens under the action of hydraulic oil, which can facilitate the control of the one-way valve 13 and reduce the production cost.

[0085] Further, as shown in Figure 4 , the pilot oil passage 123 can be in communication with the second oil passage 122, that is, part of the hydraulic oil entering the second oil passage 122 flows into the rod cavity 1111b to drive the telescopic rod 1113 to retract relative to the cylinder body 1111, and the other part of the hydraulic oil flows into the pilot oil passage 123 to reversely open the one-way valve 13. In this way, the oil passage of the hydraulic circuit 12 can be simplified, and the hydraulic oil can be introduced into the pilot oil passage 123.

[0086] In other embodiments, the pilot oil passage 123 can not be in communication with the second oil passage 122, that is, the hydraulic oil can be introduced into the pilot oil passage 123 from other positions of the hydraulic circuit 12.

[0087] In addition, the one-way valve 13 capable of reversely opening under control in the embodiment is not limited to the above-mentioned hydraulic control one-way valve. In other embodiments, the one-way valve 13 can be any one-way valve capable of reversely opening under control, such as an electric control one-way valve.

[0088] In some embodiments, as shown in Figure 1 , Figure 2 , Figure 5 and Figure 12 , the mold core pulling mechanism 10 can further include a guide sleeve 15, and the insert pin 112 is arranged in the guide sleeve 15 and can slide relative to the guide sleeve 15.

[0089] Specifically, the guide sleeve 15 is fixed relative to the pin 112, for example, the guide sleeve 15 can be fixed on the first mold body, and the pin 112 can slide relative to the guide sleeve 15 under the driving of the telescopic rod 1113.

[0090] The guide sleeve 15 can ensure that the pin 112 is more stable during movement and is not prone to jamming and the like.

[0091] Further, referring to Figure 12 The outer side wall of the guide sleeve 15 can also have a recessed cooling groove 15a for passing a cooling medium.

[0092] Since the cooling groove 15a is an open structure, in actual application, the guide sleeve 15 needs to cooperate with other components to enable the cooling medium to flow in the cooling groove 15a. Exemplarily, for the guide sleeve 15 fixed on the first mold body, the first mold body can have a cooling flow channel, and the guide sleeve 15 and the first mold body can be sealed to seal and close the cooling groove 15a, and the cooling flow channel communicates with the cooling groove 15a. That is, the guide sleeve 15 and the first mold body can be sealed by using a sealing ring or an interference fit, and after sealing, a closed space is formed in the cooling groove 15a, the cooling medium can flow into the cooling groove 15a along the cooling flow channel, and the cooling medium in the cooling groove 15a can also flow into the cooling flow channel, so that the cooling medium can flow in the cooling groove 15a.

[0093] The cooling medium can flow in the cooling groove 15a to cool the pin 112, thereby preventing the pin 112 from being overheated during injection molding and affecting the service life of the pin 112 and the molding stability of the molded product 200.

[0094] In the description of the present application, the description of the terms "in an embodiment", "in some embodiments", "in another embodiment", "in yet another embodiment", or "exemplary" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the exemplary description of the above terms is not necessarily for the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, the skilled in the art can combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0095] The above descriptions are only the preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, and the like made within the principle and technical scope of the present application are included in the protection scope of the present application.

Claims

1. A mold core-pulling mechanism, characterized in that, include: A core-pulling assembly, comprising a hydraulic cylinder and a pin, wherein the hydraulic cylinder comprises a cylinder body, a piston, and a telescopic rod, the piston being slidably disposed within the cylinder body and having a rodless chamber and a rod chamber separated within the cylinder body, the telescopic rod being connected to the piston and extending out of the cylinder body through the rod chamber, and the pin being fixed to the telescopic rod; The hydraulic circuit includes a first oil passage communicating with the rodless chamber and a second oil passage communicating with the rod chamber; A controllable reverse-flow check valve is provided in the first oil circuit, and the forward flow direction of the check valve is toward the hydraulic cylinder.

2. The mold core-pulling mechanism according to claim 1, characterized in that, The check valve has a forward inlet, a forward outlet, and a control port. The hydraulic circuit includes a pilot oil circuit. The forward outlet is connected to the rodless chamber, and the pilot oil circuit is connected to the control port to achieve controlled reverse conduction of the check valve.

3. The mold core-pulling mechanism according to claim 2, characterized in that, The pilot oil circuit is connected to the second oil circuit.

4. The mold core-pulling mechanism according to claim 1, characterized in that, The check valve is an electrically controlled check valve.

5. The mold core-pulling mechanism according to any one of claims 1-4, characterized in that, The number of core-pulling assemblies is multiple. The first oil circuit includes a first main oil circuit and first sub-oil circuits corresponding to the core-pulling assemblies. Each first sub-oil circuit is connected in parallel with each other, and each first sub-oil circuit is connected to the rodless chamber of the hydraulic cylinder of the corresponding core-pulling assembly. The first main oil circuit is connected to each first sub-oil circuit. The one-way valve is disposed in the first main oil circuit. And / or, the number of core-pulling assemblies is multiple, the second oil circuit includes a second main oil circuit and second sub-oil circuits corresponding one-to-one with the core-pulling assembly, each second sub-oil circuit is connected in parallel with each other, and each second sub-oil circuit is respectively connected to the rod chamber of the hydraulic cylinder of the corresponding core-pulling assembly, and the second main oil circuit is respectively connected to each second sub-oil circuit.

6. The mold core-pulling mechanism according to any one of claims 1-4, characterized in that, The core-pulling assembly also includes an adapter rod, which is detachably connected to the telescopic rod and the insert pin, respectively.

7. The mold core-pulling mechanism according to claim 6, characterized in that, The adapter rod is inserted into the telescopic rod, and the adapter rod and the telescopic rod are anti-rotationally engaged; And / or, the adapter rod engages with the insert pin.

8. The mold core-pulling mechanism according to claim 7, characterized in that, The core-pulling assembly also includes an anti-rotation block; A portion of the outer side wall of the telescopic rod forms an anti-rotation mating surface. The anti-rotation block is located on the periphery of the adapter rod and protrudes from the end of the adapter rod near the telescopic rod. The anti-rotation block and the anti-rotation mating surface face each other and form a mutual restraint in the rotation direction of the adapter rod. Alternatively, a portion of the outer side wall of the adapter rod forms an anti-rotation mating surface, the anti-rotation block is located on the periphery of the telescopic rod and protrudes from the end of the telescopic rod near the adapter rod; the anti-rotation block and the anti-rotation mating surface face each other and form a mutual restraint in the rotation direction of the adapter rod.

9. The mold core-pulling mechanism according to claim 7, characterized in that, The insert includes a needle body and a snap-fit ​​block disposed at one end of the needle body, the snap-fit ​​block protruding from the outer side wall of the needle body; the adapter rod has a slot at one end near the insert and a clearance groove on the side of the slot away from the telescopic rod, the slot and the clearance groove are connected, and a stepped surface facing the slot is formed on the periphery of the connection. The slot has a first opening, and the clearance groove has a second opening and a third opening. The first opening and the second opening are both located on the outer side wall of the adapter rod. The third opening is located on the side of the clearance groove that is far away from the slot. The third opening avoids the needle body, allowing the locking block to be engaged into the slot through the first opening, and a part of the needle body enters the clearance groove through the second opening.

10. The mold core-pulling mechanism according to any one of claims 1-4, characterized in that, The mold core-pulling mechanism also includes a guide sleeve, in which the insert pin passes and can slide relative to the guide sleeve.

11. The mold core-pulling mechanism according to claim 10, characterized in that, The outer wall of the guide sleeve has a recessed cooling groove.

12. An injection mold, characterized in that, include: First motif; A second mold body is formed by detachably docking with the first mold body to form a cavity; The mold core-pulling mechanism according to any one of claims 1-11, wherein the mold core-pulling mechanism is disposed on the first mold body, and the telescopic rod extends to allow the insert pin to extend into the cavity.

13. The injection mold according to claim 12, characterized in that, The mold core-pulling mechanism further includes a guide sleeve, in which the insert pin passes and can slide relative to the guide sleeve; the outer surface of the guide sleeve has a recessed cooling groove, the first mold body has a cooling channel, the guide sleeve is fixed to the first mold body, and the guide sleeve and the first mold body are sealed to seal the cooling groove, and the cooling channel is connected to the cooling groove.

Images