CN206326807U - A kind of pressure injection mold of wood plastics tray - Google Patents

Abstract

The utility model discloses an injection mold for a wood-plastic tray, which comprises a fixed mold assembly, a movable mold assembly and a compression assembly. The upper mold plate of the fixed mold assembly is provided with a wedge-shaped groove and a pallet foot groove, and the movable mold assembly The lower formwork is provided with wedge blocks and inserts, the wedge blocks match the wedge grooves, and the inserts match the tray foot grooves; the oil motor of the compression assembly is installed on the support plate of the movable mold assembly, and the gear of the compression assembly is installed On the output shaft of the oil motor and meshed with the rack, one end of the rack is fixed on the lower mold backing plate of the movable mold assembly. One-time molding of wood-plastic trays on ordinary injection machines, especially large and medium-sized wood-plastic trays, expands the use range of conventional injection machines, effectively shortens the molding cycle of trays, and is easy to realize automation. The compression action is realized through the transmission of the rack and pinion, the compression distance and speed are easy to adjust, and the compression distance and speed can be adjusted according to the performance requirements of the molded product, and the control accuracy is high, and the displacement detection error is small.

Description

Injection mold for wood-plastic pallet

technical field

The utility model belongs to the technical field of tray molding, in particular to a wood-plastic tray and an injection mold thereof.

Background technique

Pallets can be used to store, load, and move goods, and are one of the essential logistics equipment in modern logistics warehousing. Among them, wooden pallets do not meet the needs of intelligent manufacturing due to limited material resources, easy moths and moisture. Due to its beautiful appearance and unique performance, plastic pallets are widely used in internal circulation of enterprises, especially in intelligent storage. However, in the current pallet market, wooden pallets account for 90%, while plastic pallets only account for about 8%, and the market share is relatively small. Tracing it to its cause is mainly because the structure of the plastic tray is complicated, and the cost of one injection molding is relatively high, so it is difficult to popularize.

There are currently four molding methods for plastic trays: the first is injection molding. The plastic pallet products produced by the method are flat, bright and clean, crisp and dense, and have a large degree of freedom in product design. They are divided into double-sided integral plastic pallets and double-sided assembled plastic pallets. Among them, the double-sided integral tray generally has a self-weight of more than 15 kg/piece, and its shape is relatively complicated. It requires an injection molding machine with a clamping force of more than 2,500 tons to produce. This type of tray has complex shape, large investment and relatively high cost. Generally, not many plastic processing plants use this method. The second is the extrusion-hollow blow molding method. This method is similar to the general hollow product blow molding method, because the product is large and double-sided, requiring a large extruder, mold clamping machine and mold. The third is the vacuum blister forming method. This method requires large-scale vacuum blister equipment for production and molding, and the equipment cost is low, and the mold cost is also low, but the product wall thickness is uneven. The fourth is the extrusion molding method. The plastic trays produced by this method are all assembled, the product structure is single, and the strength is unstable.

Wood-plastic composites (Wood-Plastic Composites, WPC) is a new type of composite material that has been booming at home and abroad in recent years. It refers to the use of polyethylene, polypropylene, polyvinyl chloride, etc., instead of the usual resin adhesive, and more than 35%-70% of waste plant fibers such as wood powder, rice husk, straw, etc. to mix into new wood materials. The advantages of wood-plastic materials are (1) abundant sources and low cost. (2) Waterproof, moisture-proof, insect-proof and termite-proof. (3) High environmental protection, no pollution, no pollution, and recyclable. (4) High fire resistance. (5) Good machinability. (6) No cracking, no swelling, no deformation.

However, the raw material of wood-plastic products is plastic + wood powder (35%-70%) + coupling agent + others, and the fluidity after melting is very poor, which is limited by the structure of the injection mold and the injection pressure, injection speed and clamping force of the injection molding machine. When forming larger products, it is difficult for wood-plastic materials to fill the cavity smoothly. To solve this problem, at present, it is mainly solved by increasing the parameters of the injection molding machine such as increasing the injection pressure, injection speed and clamping force, which will blindly increase the cost and consume a lot of energy.

Although the cost of wood-plastic materials is low, its molding has obvious defects, that is, its fluidity is insufficient, and it is easy to have under-injection, especially for large-scale wood-plastic products formed at one time. At present, the method to solve this problem is mainly to increase the injection pressure, injection speed and clamping force. The process cost is high, the energy consumption is large, and the requirements for molding equipment are high. Moreover, when the product is large, short shots are prone to occur, and the forming is incomplete.

The injection molding method is to apply a low clamping force to the mold, first not completely close the mold, apply a small injection pressure to fill the mold cavity, and then compress the mold to completely close it to form the product. Injection compression molding requires the use of an injection molding machine with a secondary clamping device to complete the secondary compression of the mold. This equipment is expensive and is not suitable for all injection molding factories.

Utility model content

The utility model aims to solve technical problems such as difficulty in injection molding of existing wood-plastic materials, high production cost, inability to form large and medium-sized wood-plastic trays at one time, and high price of injection molds, so as to provide a low injection cost and easy one-time molding. Injection mold for wood-plastic pallets.

In order to solve the problems of the technologies described above, the technical scheme adopted in the utility model is as follows:

An injection mold for wood-plastic pallets, comprising a fixed mold assembly, a movable mold assembly, and a compression assembly, wedge-shaped grooves and tray foot grooves are arranged on the upper template of the fixed mold assembly, and the lower template of the movable mold assembly is provided with There are wedge blocks and inserts, the wedge blocks match the wedge grooves, and the inserts match the tray foot slots; the oil motor of the compression assembly is installed on the support plate of the movable mold assembly, and the gear of the compression assembly is installed on the output of the oil motor On the shaft and meshed with the rack, one end of the rack is fixed on the lower mold backing plate of the movable mold assembly.

The fixed mold assembly includes an upper mold bottom plate and an upper mold plate, the upper mold plate is fixedly installed on the lower end of the upper mold bottom plate, wedge-shaped grooves are arranged on the lower end surface of the upper mold plate, and pallet foot grooves are arranged between the wedge-shaped grooves.

A spring limiting hole is arranged on the lower end surface of the upper template.

The movable mold assembly includes a lower template, a lower mold backing plate, a cushion block, a support plate, an ejection backing plate and a lower mold bottom plate, the lower template is fixedly installed on the upper end surface of the lower mold backing plate, and the upper end surface of the upper template is provided with a wedge-shaped The wedge-shaped blocks correspond to the wedge-shaped grooves; there are inserts between the wedge-shaped blocks, and the inserts correspond to the foot grooves of the pallet; a pad is installed at the lower end of the backing plate of the lower mold, and a support plate is installed at the lower end of the pad. The lower end of the support plate is provided with an ejection backing plate, and the ejection backing plate is installed on the bottom plate of the lower mold.

A spring is arranged on the upper end surface of the lower template, and the spring corresponds to the spring limiting hole on the upper template.

The compression assembly includes an oil motor, a gear and a rack. The oil motor is installed at the lower end of the support plate of the moving mold assembly. The gear is connected to the output shaft of the oil motor and meshed with the rack. One end of the rack is fixed on the moving mold The lower end of the die backing plate of the component.

A limit hole is arranged on the spacer, a limit screw is installed on the lower mold backing plate at a position corresponding to the limit hole, and the lower end of the limit screw is inserted into the limit hole. The setting of the limit screw and the limit hole limits the distance that the rack can move upwards to ensure the quality of the pallet.

The utility model can carry out one-time molding of wood-plastic trays on ordinary injection machines, especially large and medium-sized wood-plastic trays, expands the use range of conventional injection machines, effectively shortens the molding cycle of trays, and is easy to realize automation. The compression action is realized through the transmission of the rack and pinion, the compression distance and speed are easy to adjust, and the compression distance and speed can be adjusted according to the performance requirements of the molded product, and the control accuracy is high, and the displacement detection error is small. The wedge structure is designed to ensure the positioning accuracy of the injection compression mold and overcome the defect of easy material leakage. When designing the ejection system of the mold, the height of the ejection backing plate can be flexibly adjusted, and the ejection distance can be adjusted to avoid interference between the ejection system and the rack.

Description of drawings

Fig. 1 is the structural representation of the utility model.

detailed description

As shown in Figure 1, an injection mold for a wood-plastic pallet includes a fixed mold assembly, a movable mold assembly and a compression assembly, and the upper template 2 of the fixed mold assembly is provided with a wedge-shaped groove 2-1 and a pallet foot groove 2-3, the lower template 4 of the movable mold assembly is provided with a wedge block 4-1 and an insert 21, the wedge block 4-1 is matched with the wedge groove 2-1, and the insert 21 is matched with the tray foot groove 2-3 Cooperate; the oil motor 8 of the compression assembly is installed on the support plate 7 of the movable mold assembly, the gear 19 of the compression assembly is installed on the output shaft of the oil motor 8 and meshed with the rack 17, and one end of the rack 17 is fixed on the moving die assembly. On the lower mold backing plate 5 of the mold assembly.

Specifically, the fixed mold assembly includes an upper mold bottom plate 1 and an upper mold plate 2, and the upper mold plate 2 is fixedly installed on the lower end of the upper mold bottom plate 1, and a wedge-shaped groove 2-1 is arranged on the lower end surface of the upper mold plate 2, and the wedge-shaped groove 2 Tray foot slots 2-3 are arranged between -1.

Preferably, a spring limiting hole 2-2 is provided on the lower end surface of the upper template 2 .

The movable mold assembly includes a lower template 4, a lower mold backing plate 5, a cushion block 6, a support plate 7, an ejection backing plate 9 and a lower mold bottom plate 11, and the lower template 4 is fixedly installed on the lower mold backing plate 5 by screws. end face. And the upper template 2 and the lower template 4 form the mold cavity of the tray. A spring 3 is arranged on the upper end surface of the lower template 4 , and the spring 3 corresponds to the spring limiting hole 2 - 2 on the upper template 2 .

A wedge-shaped block 4-1 is provided on the upper surface of the upper template 4, and the wedge-shaped block 4-1 corresponds to the wedge-shaped groove 2-1. An insert 21 is arranged between the wedge blocks 4-1, and the insert 21 corresponds to the pallet foot groove 2-3. A cushion block 6 is installed at the lower end of the lower mold backing plate 5 . A limit hole 6-1 is set on the spacer 6, and a limit screw 20 is installed on the lower mold backing plate 5 corresponding to the limit hole 6-1, and the lower end of the limit screw 20 is inserted into the limit hole 6-1 . The setting of the limit screw and the limit hole limits the distance that the rack can move upwards to ensure the quality of the pallet.

A support plate 7 is installed on the lower end of the cushion block 6, and an ejection backing plate 9 is installed on the lower end of the support plate 7, and the ejection backing plate 9 is installed on the bottom plate 11 of the lower mold. When designing the ejection system of the mold, the height of the ejection backing plate can be flexibly adjusted, and the ejection distance can be adjusted to avoid interference between the ejection system and the rack.

Described compression assembly comprises oil motor 8, gear 19 and rack 17, and oil motor 8 is installed on the lower end of the support plate 7 of moving mold assembly, and gear 19 is connected with the output shaft of oil motor 8 and is meshed with rack 17, One end of the tooth bar 17 is fixed on the lower end of the lower mold backing plate 5 of the movable mold assembly.

The upper formwork 2 and the lower formwork 4 of the utility model form the mold cavity of the tray. A certain compression gap is reserved between the upper template 2 and the lower template 4 through the spring 3, and the gap value can be adjusted by applying different types of springs. In order to better position the mold and prevent the wood-plastic melt from leaking through the compression gap, a wedge mechanism is designed between the upper template 2 and the lower template 4. The two sides of the wedge are inclined and straight, and the straight can prevent the melt Leakage, the slope can be positioned. The compression function of the mold is mainly completed by the gear 19 and the rack 17, the compression power comes from the oil motor 8, the oil motor is fixed on the support plate 7 by screws, the gear 19 is connected to the output shaft of the oil motor, and the rack 17 is fixed by screws On the backing plate 5 of the lower mold, the oil motor 8 rotates, drives the gear 19 and the rack 17 to transmit, makes the rack 17 move up and down, and moves upward to implement the compression action, and pushes the backing plate 5 of the lower mold and the lower template 4 upward to complete the compression action. The bar moves down to complete the reset action of the mold. In order to limit the compression distance, a limit screw 20 is designed between the block 6 and the backing plate 5 of the lower mold to limit the distance of the rack moving up and down, so as to ensure the realization of the compression movement and reset action of the mold.

Working process: 1. The mold is closed for the first time under the action of the main mold clamping mechanism of the injection machine, but a certain gap is reserved between the upper template 2 and the lower template 4, and the gap is supported by the spring 3 at the same time.

2. Under relatively low injection pressure, the preset amount of molten material fills the mold cavity smoothly;

3. After the injection is completed, the oil motor 8 drives the gear 19 and the rack 17 to perform a compression action. The wood-plastic melt and the spring 3 are compressed, and the upper mold plate 2 and the lower mold plate 4 are completely closed to complete the compression action and perform compression molding.

4. After cooling, the product is molded and solidified.

5. The ejection device moves to push out the workpiece, and at the same time, the oil motor 8 drives the gear 19 and the rack 17 to move in the opposite direction, and resets the backing plate 5 and the lower template 4 of the lower mold, and the spring 3 assists in completing the reset of the movable mold side. So far, The molding process completes one cycle.

Claims (7)

1. a kind of pressure injection mold of wood plastics tray, it is characterised in that：Including cover half component, dynamic model component and compression assembly, cover half The cope plate of component（2）On be provided with wedge-shaped slot（2-1）With tray foot groove（2-3）, the lower template of dynamic model component（4）On be provided with Wedge（4-1）And mold insert（21）, wedge（4-1）With wedge-shaped slot（2-1）It is engaged, mold insert（21）With tray foot groove（2-3） It is engaged；The oil motor of compression assembly（8）Installed in the supporting plate of dynamic model component（7）On, the gear of compression assembly（19）Install In oil motor（8）Output shaft on and and tooth bar（17）It is meshed, tooth bar（17）One end be fixed on the lower die-cushion of dynamic model component Plate（5）On.

2. a kind of pressure injection mold of wood plastics tray according to claim 1, it is characterised in that：The cover half component includes upper Baffle plate（1）And cope plate（2）, cope plate（2）It is fixedly mounted on baffle plate（1）Lower end, in cope plate（2）Lower surface Wedge-shaped slot is set（2-1）, in wedge-shaped slot（2-1）Between be provided with tray foot groove（2-3）.

3. a kind of pressure injection mold of wood plastics tray according to claim 2, it is characterised in that：In cope plate（2）Lower end Face is provided with spring retainer hole（2-2）.

4. a kind of pressure injection mold of wood plastics tray according to claim 1, it is characterised in that：Under the dynamic model component includes Template（4）, lower mold backing plate（5）, cushion block（6）, supporting plate（7）, ejection backing plate（9）And lower mould bottom plate（11）, lower template（4）It is fixed Installed in lower mold backing plate（5）Upper surface, cope plate（4）Upper surface be provided with wedge（4-1）, wedge（4-1）With wedge Shape groove（2-1）It is corresponding；In wedge（4-1）Between be provided with mold insert（21）, mold insert（21）With tray foot groove（2-3）Relatively Should；In lower mold backing plate（5）Lower end cushion block is installed（6）, in cushion block（6）Lower end supporting plate is installed（7）, supporting plate（7） Lower end ejection backing plate is installed（9）, eject backing plate（9）Installed in lower mould bottom plate（11）On.

5. a kind of pressure injection mold of wood plastics tray according to claim 4, it is characterised in that：In lower template（4）Upper end Face is provided with spring（3）, spring（3）With cope plate（2）On spring retainer hole（2-2）It is corresponding.

6. a kind of pressure injection mold of wood plastics tray according to claim 1, it is characterised in that：The compression assembly includes oil Motor（8）, gear（19）And tooth bar（17）, oil motor（8）Installed in the supporting plate of dynamic model component（7）Lower end, gear（19） With oil motor（8）Output shaft connection and and tooth bar（17）It is meshed, tooth bar（17）One end be fixed on the lower mould of dynamic model component Backing plate（5）Lower end.

7. a kind of pressure injection mold of wood plastics tray according to claim 4, it is characterised in that：In cushion block（6）On be provided with Spacing hole（6-1）, in lower mold backing plate（5）Upper and spacing hole（6-1）Corresponding position is provided with stop screw（20）, spacing spiral shell Nail（20）Lower end insertion spacing hole（6-1）It is interior.